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Sample records for ah outflow pathway

  1. Variations in active outflow along the trabecular outflow pathway.

    PubMed

    Cha, Elliott D K; Xu, Jia; Gong, Lihua; Gong, Haiyan

    2016-05-01

    Previous tracer studies have shown segmental outflow in the trabecular meshwork (TM) and along the inner wall (IW) of Schlemm's canal (SC). Whether segmental outflow is conserved distal to SC has not yet been investigated. This study aims to investigate whether the segmented pattern of outflow is conserved in distal outflow pathways by using a newly developed global imaging method and to evaluate variations of active outflow in three distinct regions along trabecular outflow pathway. Six normal whole globe human eyes were first perfused at 15 mmHg to establish a stable baseline outflow facility. The anterior chamber was then exchanged (5 mL) and perfused with fluorescent microspheres (0.002% v/v, 200 μL) to label areas of active outflow. All eyes were perfusion fixed and dissected into anterior segments. The TM and scleral surface were en face imaged globally. Effective filtration area (EFA) and fluorescent tracer distribution and intensity were analyzed in global images for both the TM and episcleral veins (EPVs). Anterior segments were further dissected into a minimum of 16 radial wedges, from which frontal sections were cut, stained, and imaged, using confocal microscopy. EFA from all three locations along the trabecular outflow pathway were measured and compared. Additionally, TM thickness, SC height, and total number of collector channels (CC) were analyzed and compared between active and inactive areas of outflow. Statistical analysis was performed using Student's t-tests and Wilcoxon signed-rank test with a required significance of p ≤ 0.05. All three locations showed a segmental outflow pattern. The TM had a significantly higher mean EFA (86.3 ± 3.5%) compared to both the IW (34.7 ± 2.9%; p ≤ 0.01) and EPVs (41.1 ± 3.8%; p ≤ 0.01). No significant difference in mean EFA was found between IW and EPVs. Preferential active outflow was observed in the nasal and inferior quadrants. TM thickness was significantly larger in areas of active

  2. The autophagic lysosomal system in outflow pathway physiology and pathophysiology.

    PubMed

    Liton, Paloma B

    2016-03-01

    Malfunction of the trabecular meshwork (TM)/schlemm's canal (SC) conventional outflow pathway is associated with elevated intraocular pressure (IOP) and, therefore, increased risk of developing glaucoma, a potentially blinding disease affecting more than 70 million people worldwide. This TM/SC tissue is subjected to different types of stress, including mechanical, oxidative, and phagocytic stress. Long-term exposure to these stresses is believed to lead to a progressive accumulation of damaged cellular and tissue structures causing permanent alterations in the tissue physiology, and contribute to the pathologic increase in aqueous humor (AH) outflow resistance. Autophagy is emerging as an essential cellular survival mechanism against a variety of stressors. In addition to performing basal functions, autophagy acts as a cellular survival pathway and represents an essential mechanism by which organisms can adapt to acute stress conditions and repair stress-induced damage. A decline in autophagy has been observed in most tissues with aging and has been considered responsible, at least in part, for the accumulation of damaged cellular components in almost all tissues of aging organisms. Dysfunction in the autophagy pathway is associated with several human diseases, from infectious diseases to cancer and neurodegeneration. In this review, we will summarize our current knowledge of the emerging roles of autophagy in outflow tissue physiology and pathophysiology, including novel evidence suggesting compromised autophagy in the glaucomatous outflow pathway.

  3. Effects of Prostaglandin Analogues on Aqueous Humor Outflow Pathways

    PubMed Central

    Winkler, Nelson S.

    2014-01-01

    Abstract Elevated intraocular pressure (IOP) is the most prevalent risk factor for glaucoma. All treatments, whether surgical or pharmaceutical, are aimed at lowering IOP. Prostaglandin analogues are a first line therapy for glaucoma due to their ability to reduce IOP, once-daily dosing, efficacy, and minimal side-effect profile. Whereas prostaglandin analogues have been known to alter aqueous humor outflow through the unconventional (uveoscleral) pathway, more recent evidence suggests their action also occurs through the conventional (trabecular) pathway. Understanding how prostaglandin analogues successfully lower IOP is important, as this information may lead to the discovery of new molecular targets for future therapeutic intervention. This review explores the current understanding of prostaglandin analogue biology as it pertains to IOP reduction and improved aqueous humor outflow facility. PMID:24359106

  4. Activation of AhR-mediated toxicity pathway by emerging pollutants polychlorinated diphenyl sulfides

    EPA Science Inventory

    Polychlorinated diphenyl sulfides (PCDPSs) are a group of environmental pollutants for which limited toxicological information is available. This study tested the hypothesis that PCDPSs could activate the mammalian aryl hydrocarbon receptor (AhR) mediated toxicity pathways. Eight...

  5. TCDD and omeprazole prime platelets through the aryl hydrocarbon receptor (AhR) non-genomic pathway.

    PubMed

    Pombo, Mónica; Lamé, Michael W; Walker, Naomi J; Huynh, Danh H; Tablin, Fern

    2015-05-19

    The role of the aryl hydrocarbon receptor (AhR) in hemostasis has recently gained increased attention. Here, we demonstrate, by qRT-PCR and western blot, that human platelets express both AhR mRNA and AhR protein. AhR protein levels increase in a dose dependent manner when incubated with either 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or omeprazole. Treatment of platelets with puromycin blocks increased AhR protein synthesis in the presence of AhR activators. Additionally, treatment of platelets with either activator results in phosphorylation of p38MAPK and cPLA2, two key signaling molecules in platelet activation pathways. Using the AhR competitive inhibitors alpha naphthoflavone and CH-223191, we show that phosphorylation of p38MAPK is AhR dependent. Further, inhibition of p38MAPK blocks downstream cPLA2 phosphorylation induced by TCDD or omeprazole. Treatment with AhR activators results in platelet priming, as demonstrated by increased platelet aggregation, which is inhibited by AhR antagonists. Our data support a model of the platelet AhR non-genomic pathway in which treatment with AhR activators results in increased expression of the AhR, phosphorylation of p38MAPK and cPLA2, leading to platelet priming in response to agonist. PMID:25797602

  6. Induction of human UGT1A1 by bilirubin through AhR dependent pathway.

    PubMed

    Togawa, Hiroshi; Shinkai, Shigeko; Mizutani, Takaharu

    2008-12-01

    UDP-glucuronosyltransferase1A1 (UGT1A1) plays a key role to conjugate bilirubin and preventing jaundice, but there is no report showing the induction of human UGT1A1 (UGT1A1) by bilirubin. In this report, we show findings of the induction of the reporter gene (-3475/+14) of UGT1A1 in HepG2 cells by bilirubin at 50 microM, 100 microM, with human aryl hydrocarbon receptor (hAhR). We confirmed that induction of the reporter gene by bilirubin is dependent on the position of the xenobiotic responsive element (XRE) (-3328/-3319) of UGT1A1, because the XRE deletion UGT1A1 gene did not respond to stimulation by a complex of bilirubin and hAhR. alpha-Naphthoflavone (alpha-NF) of a typical AhR antagonist at 50 microM inhibited induction by bilirubin, suggesting that bilirubin stimulates through binding with hAhR. Meanwhile, bilirubin itself did not stimulate the induction of AhR, because we detected no-elevation of the mRNA level of AhR by RT-PCR. These results indicate that the induction of UGT1A1 by bilirubin-AhR did not depend on the elevation of AhR but on ligand binding. From this result, we considered that high bilirubin in neonates must induce the elevation of UGT1A1 after birth to prevent jaundice, and bilirubin in adults also regulates the level of UGT1A1. This is the first report showing direct induction of UGT1A1 by a bilirubin through AhR pathway. PMID:19356098

  7. Transport Pathways for Asian Pollution Outflow Over the Pacific: Interannual and Seasonal Variations

    NASA Technical Reports Server (NTRS)

    Liu, Hong-Yu; Jacob, Daniel J.; Bey, Isabelle; Yantosca, Robert M.; Duncan, Bryan N.; Sachse, Glen W.

    2003-01-01

    The meteorological pathways contributing to Asian pollution outflow over the Pacific are examined with a global three-dimensional model analysis of CO observations from the Transport and Chemical Evolution over the Pacific (TRACE-P) aircraft mission (February-April 2001). The model is used also to place the TRACE-P observations in an interannual (1994-2001) and seasonal context. The major process driving Asian pollution outflow in spring is frontal lifting ahead of southeastward-moving cold fronts (the leading edge of cold surges) and transport in the boundary layer behind the cold fronts. Orographic lifting over central and eastern China combines with the cold fronts to promote the transport of Chinese pollution to the free troposphere. Outflow of seasonal biomass burning in Southeast Asia during spring takes place mostly by deep convection but also by northeastward transport and frontal lifting, mixing with the anthropogenic outflow. Boundary layer outflow over the western Pacific is largely devoid of biomass burning influence. European and African (biomass burning) plumes in Asian outflow during TRACE-P were weak (less than 60 ppbv and 20 ppbv CO, respectively) and were not detectable in the observations because of superposition of the much larger Asian pollution signal. Spring 2001 (La Nina) was characterized by unusually frequent cold surge events in the Asian Pacific rim and strong convection in Southeast Asia, leading to unusually strong boundary layer outflow of anthropogenic emissions and convective outflow of biomass burning emissions in the upper troposphere. The Asian outflow flux of CO to the Pacific is found to vary seasonally by a factor of 3-4 (maximum in March and minimum in summer). The March maximum results from frequent cold surge events and seasonal biomass burning emissions.

  8. The Outflow Pathway: A Tissue With Morphological and Functional Unity.

    PubMed

    Saccà, Sergio Claudio; Gandolfi, Stefano; Bagnis, Alessandro; Manni, Gianluca; Damonte, Gianluca; Traverso, Carlo Enrico; Izzotti, Alberto

    2016-09-01

    The trabecular meshwork (TM) plays an important role in high-tension glaucomas. Indeed, the TM is a true organ, through which the aqueous humor flows from the anterior chamber to Schlemm's canal (SC). Until recently, the TM, which is constituted by endothelial-like cells, was described as a kind of passive filter. In reality, it is much more. The cells delineating the structures of the collagen framework of the TM are endowed with a cytoskeleton, and are thus able to change their shape. These cells also have the ability to secrete the extracellular matrix, which expresses proteins and cytokines, and are capable of phagocytosis and autophagy. The cytoskeleton is attached to the nuclear membrane and can, in millionths of a second, send signals to the nucleus in order to alter the expression of genes in an attempt to adapt to biomechanical insult. Oxidative stress, as happens in aging, has a deleterious effect on the TM, leading eventually to cell decay, tissue malfunction, subclinical inflammation, changes in the extracellular matrix and cytoskeleton, altered motility, reduced outflow facility, and (ultimately) increased IOP. TM failure is the most relevant factor in the cascade of events triggering apoptosis in the inner retinal layers, including ganglion cells. J. Cell. Physiol. 231: 1876-1893, 2016. © 2016 Wiley Periodicals, Inc.

  9. The Outflow Pathway: A Tissue With Morphological and Functional Unity.

    PubMed

    Saccà, Sergio Claudio; Gandolfi, Stefano; Bagnis, Alessandro; Manni, Gianluca; Damonte, Gianluca; Traverso, Carlo Enrico; Izzotti, Alberto

    2016-09-01

    The trabecular meshwork (TM) plays an important role in high-tension glaucomas. Indeed, the TM is a true organ, through which the aqueous humor flows from the anterior chamber to Schlemm's canal (SC). Until recently, the TM, which is constituted by endothelial-like cells, was described as a kind of passive filter. In reality, it is much more. The cells delineating the structures of the collagen framework of the TM are endowed with a cytoskeleton, and are thus able to change their shape. These cells also have the ability to secrete the extracellular matrix, which expresses proteins and cytokines, and are capable of phagocytosis and autophagy. The cytoskeleton is attached to the nuclear membrane and can, in millionths of a second, send signals to the nucleus in order to alter the expression of genes in an attempt to adapt to biomechanical insult. Oxidative stress, as happens in aging, has a deleterious effect on the TM, leading eventually to cell decay, tissue malfunction, subclinical inflammation, changes in the extracellular matrix and cytoskeleton, altered motility, reduced outflow facility, and (ultimately) increased IOP. TM failure is the most relevant factor in the cascade of events triggering apoptosis in the inner retinal layers, including ganglion cells. J. Cell. Physiol. 231: 1876-1893, 2016. © 2016 Wiley Periodicals, Inc. PMID:26754581

  10. Endothelial glycocalyx layer in the aqueous outflow pathway of bovine and human eyes.

    PubMed

    Yang, Chen-Yuan Charlie; Huynh, Tiffany; Johnson, Mark; Gong, Haiyan

    2014-11-01

    The glycocalyx layer on the vascular endothelium is known to have an important role as a transport barrier and in the mechanotransduction of fluid shear stress. The detailed structure and distribution of the glycocalyx in the bovine and human aqueous humor outflow pathways has not yet been reported. The purpose of this study was to determine whether this layer exists in the bovine and human aqueous outflow pathways and to compare the distribution and thickness therein. Enucleated bovine (N = 4) and human (N = 4) eyes were fixed using Alcian Blue to preserve the glycocalyx. The glycocalyx distribution and thickness (in regions where it was seen) were measured on the trabecular beams (TM), Schlemm's canal (SC)/aqueous plexus (AP), and collector channels (CC). The glycocalyx, which appears as a layer of hair-like brushes, coats the surface of the endothelium non-uniformly in the bovine and human aqueous outflow pathways with a thickness in bovine eyes of 68-122 nm and in human eyes of 52-166 nm (25th to 75th percentiles). The distribution of the glycocalyx in different regions of the outflow pathway is not the same between bovine and human eyes. In both species, the glycocalyx was most uniform in the CCs. Less coverage of glycocalyx was found in the AP than the TM in bovine eyes, while more coverage was found in SC than the TM in human eyes. Most interestingly, glycocalyx was also found filling most pores of the endothelium of AP/SC in both bovine and human eyes. Glycocalyx was usually not found coating the inner membranes of the giant vacuoles (GVs); however, in GVs with a visible pore, glycocalyx was frequently observed on the inner membranes of the GVs. Based on our findings and those from the vascular endothelium, it is likely that the glycocalyx in SC plays a role in transduction of shear stress and perhaps regulation of outflow resistance.

  11. Importance of accessory outflow pathways in hydrocephalus after experimental subarachnoid hemorrhage

    SciTech Connect

    Griebel, R.W.; Black, P.M.; Pile-Spellman, J.; Strauss, H.W.

    1989-02-01

    This study evaluated the changes in pathways of cerebrospinal fluid (CSF) outflow that accompanied acute and compensated hydrocephalus in the rabbit. Intraventricularly injected 99mTc antimony sulfide was used as a tracer of outflow pathways, and specified structures were counted 12 to 24 hours after injection. Fifteen rabbits were divided into three groups: 1) an acutely hydrocephalic group in which 3 cisternal injections of blood were followed by a study of CSF pressure, ventricular size, and CSF outflow pathways 1 week after the last injection; 2) a control group treated according to the same protocol, except that sterile saline was injected instead of blood; and 3) a chronic group also treated according to the same protocol but in which the animals were maintained an average of 4 weeks after the last blood injection. Ventricular size was measured by computed digitation and expressed as an area ratio of ventricle to brain (VBR). In control animals, 11.8% of the injected colloid dosage was found in cranial perineural lymphatic channels, and 4.8% appeared in the spinal cord. The mean CSF pressure was 149 +/- 20.2 mm H20 (mean +/- SE) and the mean VBR was 0.040 +/- 0.003. In animals evaluated 1 week after subarachnoid injection, accessory cranial perineural lymphatic outflow decreased significantly to 3.4%, and spinal cord activity increased to 9.8% (P less than 0.05, two-tailed t-test). These animals were hydrocephalic and had CSF pressure of 247 +/- 25.1 mm H20 (mean +/- SE) and VBR of 0.083 +/- 0.009.

  12. Regulatory crosstalk and interference between the xenobiotic and hypoxia sensing pathways at the AhR-ARNT-HIF1α signaling node

    PubMed Central

    Vorrink, Sabine U.; Domann, Frederick E.

    2014-01-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates many of the responses to toxic environmental chemicals such as TCDD or dioxin-like PCBs. To regulate gene expression, the AhR requires its binding partner, the aryl hydrocarbon receptor nuclear translocator (ARNT). ARNT is also required by the hypoxia-inducible factor-1α (HIF-1α), a crucial regulator of responses to conditions of reduced oxygen. The important role of ARNT in both the AhR and HIF-1α signaling pathways establishes a meaningful foundation for a possible crosstalk between these two vitally important signaling pathways. This crosstalk might lead to interference between the two signaling pathways and thus might play a role in the variety of cellular responses after exposure to AhR ligands and reduced oxygen availability. This review focuses on studies that have analyzed the effect of low oxygen environments and hypoxiamimetic agents on AhR signaling and conversely, the effect of AhR ligands, with a special emphasis on PCBs, on HIF-1α signaling. We highlight studies that assess the role of ARNT, elucidate the mechanism of the crosstalk, and discuss the physiological implications for exposure to AhR-inducing compounds in the context of hypoxia. PMID:24824450

  13. Molecular characterization of the aryl hydrocarbon receptor (AhR) pathway in goldfish (Carassius auratus) exposure to TCDD: the mRNA and protein levels.

    PubMed

    Lu, Ming; Chang, Ziwei; Bae, Min-Ji; Oh, Seung Min; Chung, Kyu-Hyuck; Park, Jang-Su

    2013-08-01

    In bony fish or other aquatic vertebrates, the aryl hydrocarbon receptor (AhR) signaling pathway is initiated by exposure to polycyclic (or/and halogenated) aromatic hydrocarbons (PAHs, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD), which subsequently induces the up-regulated expression of a series of related genes (such as cytochrome P4501A (CYP1A)). However, a lack of applicable protein reagents hinders our further understanding of the AhR signaling pathway, which focuses only on gene-based investigations. The goldfish (Carassius auratus) is an ideal model for a study of environmental pollution in whole-Asian fresh water. Here, three sensitive and specific polyclonal antisera against goldfish AhR1, AhR2, and CYP1A proteins were developed. These antisera not only bound the in-vitro synthesized target proteins, but recognized the real proteins expressed in goldfish tissues, with minimal cross-reactivity to non-specific proteins. Together with the analysis of semi-quantitative RT-PCR and polyclonal-antibody-based sandwich ELISA, we confirmed that goldfish AhRs differed in the expression (mRNA and protein levels) patterns among test tissues. Importantly, the relative abundance of each AhR mRNA levels from the different tissues showed no obvious consistency with their protein levels. After exposure to TCDD, goldfish AhR2 showed a more sensitivity than AhR1, and stimulated CYP1A expression directly, similar with the other reported fish models. Overall, development of these antibodies in this study will allow valuable and versatile investigations to further understand the AhR signaling pathway, and different expression (mRNA and protein) patterns represent the first step in determining the regulatory mechanisms underlying the TCDD-exposed aquatic environment.

  14. The three-dimensional organisation of the post-trabecular aqueous outflow pathway and limbal vasculature in the mouse.

    PubMed

    van der Merwe, Elizabeth L; Kidson, Susan H

    2014-08-01

    The mouse eye has been used as a model for studies on the microanatomy of the outflow pathways but most of what is known comes from histological sections. These studies have focused mainly on the morphological features of the trabecular meshwork, Schlemm's canal and aqueous channels that link to the superficial episcleral vasculature. However, the anatomical architecture of the aqueous outflow vessels and their relationship to each other and to the general vascular circulation is not well understood. The aim of this study was to provide a detailed description of the microarchitecture of the aqueous outflow vessels and their relationship to the superficial limbal/episcleral vasculature throughout the entire limbus. The aqueous outflow vessels and blood and lymphatic vessels were imaged in PECAM-1 and LYVE-1 immunostained whole anterior segments of adult mice and three-dimensional (3-D) reconstructions of the optical sections were generated to reveal the aqueous, blood and lymphatic architecture. The arterial supply, venous drainage, organisation of perilimbal vasculature, collector channels/aqueous veins and the morphology of Schlemm's canal were revealed in their entirety and the relationships between these structures is described. Schlemm's canal was PECAM-1 positive but there was no affinity for the lymphatic marker LYVE-1. We show that Schlemm's canal is a continuous circular structure and more often seen as a single, broad, varicose vessel with short regions appearing as a plexus. Aqueous veins link Schlemm's canal to the superficial vasculature and there were no direct links seen between the canal and the lymphatic vessels.

  15. Mapping Molecular Differences and Extracellular Matrix Gene Expression in Segmental Outflow Pathways of the Human Ocular Trabecular Meshwork

    PubMed Central

    Vranka, Janice A.; Bradley, John M.; Yang, Yong-Feng; Keller, Kate E.; Acott, Ted S.

    2015-01-01

    Elevated intraocular pressure (IOP) is the primary risk factor for glaucoma, and lowering IOP remains the only effective treatment for glaucoma. The trabecular meshwork (TM) in the anterior chamber of the eye regulates IOP by generating resistance to aqueous humor outflow. Aqueous humor outflow is segmental, but molecular differences between high and low outflow regions of the TM are poorly understood. In this study, flow regions of the TM were characterized using fluorescent tracers and PCR arrays. Anterior segments from human donor eyes were perfused at physiological pressure in an ex vivo organ culture system. Fluorescently-labeled microspheres of various sizes were perfused into anterior segments to label flow regions. Actively perfused microspheres were segmentally distributed, whereas microspheres soaked passively into anterior segments uniformly labeled the TM and surrounding tissues with no apparent segmentation. Cell-tracker quantum dots (20 nm) were localized to the outer uveal and corneoscleral TM, whereas larger, modified microspheres (200 nm) localized throughout the TM layers and Schlemm’s canal. Distribution of fluorescent tracers demonstrated a variable labeling pattern on both a macro- and micro-scale. Quantitative PCR arrays allowed identification of a variety of extracellular matrix genes differentially expressed in high and low flow regions of the TM. Several collagen genes (COL16A1, COL4A2, COL6A1 and 2) and MMPs (1, 2, 3) were enriched in high, whereas COL15A1, and MMP16 were enriched in low flow regions. Matrix metalloproteinase activity was similar in high and low regions using a quantitative FRET peptide assay, whereas protein levels in tissues showed modest regional differences. These gene and protein differences across regions of the TM provide further evidence for a molecular basis of segmental flow routes within the aqueous outflow pathway. New insight into the molecular mechanisms of segmental aqueous outflow may aid in the design

  16. Effects of 4-nitrophenol on expression of the ER-α and AhR signaling pathway-associated genes in the small intestine of rats.

    PubMed

    Tang, Juan; Song, Meiyan; Watanabe, Gen; Nagaoka, Kentaro; Rui, Xiaoli; Li, ChunMei

    2016-09-01

    4-Nitrophenol (PNP) is a persistent organic pollutant that was proven to be an environmental endocrine disruptor. The aim of this study was to evaluate the role of the estrogen receptor-α (ER-α) and aryl hydrocarbon receptor (AhR) signaling pathway in regulating the damage response to PNP in the small intestine of rats. Wistar-Imamichi male rats (21 d) were randomly divided into two groups: the control group and PNP group. Each group had three processes that were gavaged with PNP or vehicle daily: single dose (1 d), repeated dose (3 consecutive days) (3 d), and repeated dose with recovery (3 consecutive days and 3 recovery days) (6 d). The weight of the body, the related viscera, and small intestine were examined. Histological parameters of the small intestine and the quantity of mucus proteins secreted by small goblet cells were determined using HE staining and PAS staining. The mRNA expression of AhR, ER-α, CYP1A1, and GST was measured by real-time qPCR. In addition, we also analyzed the AhR, ER-α, and CYP1A1 expression in the small intestine by immunohistochemical staining. The small intestines histologically changed in the PNP-treated rat and the expression of AhR, CYP1A1, and GST was increased. While ER-α was significantly decreased in the small intestine, simultaneously, when rats were exposed to a longer PNP treatment, the damages disappeared. Our results demonstrate that PNP has an effect on the expression of AhR signaling pathway genes, AhR, CYP1A1, and GST, and ER-α in the rat small intestine.

  17. Asian chemical outflow to the Pacific in spring: Origins, pathways, and budgets

    NASA Astrophysics Data System (ADS)

    Bey, Isabelle; Jacob, Daniel J.; Logan, Jennifer. A.; Yantosca, Robert M.

    2001-10-01

    We analyze the Asian outflow of CO, ozone, and nitrogen oxides (NOx) to the Pacific in spring by using the GEOS-CHEM global three-dimensional model of tropospheric chemistry and simulating the Pacific Exploratory Mission-West (PEM-West B) aircraft mission in February-March 1994. The GEOS-CHEM model uses assimilated meteorological fields from the NASA Goddard Earth Observing System (GEOS). It reproduces relatively well the main features of tropospheric ozone, CO, and reactive nitrogen species observed in PEM-West B, including latitudinal and vertical gradients of the Asian pollution outflow over the western Pacific although simulated concentrations of CO tend to be too low (possibly because biogenic sources are underestimated). We use CO as a long-lived tracer to diagnose the processes contributing to the outflow. The highest concentrations in the outflow are in the boundary layer (0-2 km), but the strongest outflow fluxes are in the lower free troposphere (2-5 km) and reflect episodic lifting of pollution over central and eastern China ahead of eastward moving cold fronts. This frontal lifting, followed by westerly transport in the lower free troposphere, is the principal process responsible for export of both anthropogenic and biomass burning pollution from Asia. Anthropogenic emissions from Europe and biomass burning emissions from Africa make also major contributions to the Asian outflow over the western Pacific; European sources dominate in the lower troposphere north of 40°N, while African sources are important in the upper troposphere at low latitudes. For the period of PEM-West B (February-March) we estimate that fossil fuel combustion and biomass burning make comparable contributions to the budgets of CO, ozone, and NOx. in the Asian outflow. We find that 13% of NOx emitted in Asia is exported as NOx or PAN, a smaller fraction than for the United States because of higher aerosol concentrations that promote heterogeneous conversion of NOx to HNO3

  18. Disruption of period gene expression alters the inductive effects of dioxin on the AhR signaling pathway in the mouse liver

    SciTech Connect

    Qu Xiaoyu; Metz, Richard P.; Porter, Weston W.; Cassone, Vincent M.; Earnest, David J.

    2009-02-01

    The aryl hydrocarbon receptor (AhR) and AhR nuclear translocator (ARNT) are transcription factors that express Per-Arnt-Sim (PAS) DNA-binding motifs and mediate the metabolism of drugs and environmental toxins in the liver. Because these transcription factors interact with other PAS genes in molecular feedback loops forming the mammalian circadian clockworks, we determined whether targeted disruption or siRNA inhibition of Per1 and Per2 expression alters toxin-mediated regulation of the AhR signaling pathway in the mouse liver and Hepa1c1c7 hepatoma cells in vitro. Treatment with the prototypical Ahr ligand, 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), had inductive effects on the primary targets of AhR signaling, Cyp1A1 and Cyp1B1, in the liver of all animals, but genotype-based differences were evident such that the toxin-mediated induction of Cyp1A1 expression was significantly greater (2-fold) in mice with targeted disruption of Per1 (Per1{sup ldc} and Per1{sup ldc}/Per2{sup ldc}). In vitro experiments yielded similar results demonstrating that siRNA inhibition of Per1 significantly increases the TCDD-induced expression of Cyp1A1 and Cyp1B1 in Hepa1c1c7 cells. Per2 inhibition in siRNA-infected Hepa1c1c7 cells had the opposite effect and significantly decreased both the induction of these p450 genes as well as AhR and Arnt expression in response to TCDD treatment. These findings suggest that Per1 may play a distinctive role in modulating AhR-regulated responses to TCDD in the liver.

  19. Imaging the Aqueous Humor Outflow Pathway in Human Eyes by Three-dimensional Micro-computed Tomography (3D micro-CT)

    SciTech Connect

    C Hann; M Bentley; A Vercnocke; E Ritman; M Fautsch

    2011-12-31

    The site of outflow resistance leading to elevated intraocular pressure in primary open-angle glaucoma is believed to be located in the region of Schlemm's canal inner wall endothelium, its basement membrane and the adjacent juxtacanalicular tissue. Evidence also suggests collector channels and intrascleral vessels may have a role in intraocular pressure in both normal and glaucoma eyes. Traditional imaging modalities limit the ability to view both proximal and distal portions of the trabecular outflow pathway as a single unit. In this study, we examined the effectiveness of three-dimensional micro-computed tomography (3D micro-CT) as a potential method to view the trabecular outflow pathway. Two normal human eyes were used: one immersion fixed in 4% paraformaldehyde and one with anterior chamber perfusion at 10 mmHg followed by perfusion fixation in 4% paraformaldehyde/2% glutaraldehyde. Both eyes were postfixed in 1% osmium tetroxide and scanned with 3D micro-CT at 2 {mu}m or 5 {mu}m voxel resolution. In the immersion fixed eye, 24 collector channels were identified with an average orifice size of 27.5 {+-} 5 {mu}m. In comparison, the perfusion fixed eye had 29 collector channels with a mean orifice size of 40.5 {+-} 13 {mu}m. Collector channels were not evenly dispersed around the circumference of the eye. There was no significant difference in the length of Schlemm's canal in the immersed versus the perfused eye (33.2 versus 35.1 mm). Structures, locations and size measurements identified by 3D micro-CT were confirmed by correlative light microscopy. These findings confirm 3D micro-CT can be used effectively for the non-invasive examination of the trabecular meshwork, Schlemm's canal, collector channels and intrascleral vasculature that comprise the distal outflow pathway. This imaging modality will be useful for non-invasive study of the role of the trabecular outflow pathway as a whole unit.

  20. Expression of genes for AhR and Nrf2 signal pathways in the retina of OXYS rats during the development of retinopathy and melatonin-induced changes in this process.

    PubMed

    Perepechaeva, M L; Stefanova, N A; Grishanova, A Yu

    2014-08-01

    Modulation of oxidative stress is one of the experimental approaches to the therapy of age-related macular degeneration. Melatonin holds much promise in this respect. It was hypothesized that the efficiency of melatonin in age-related macular degeneration is associated with its ability to modulate gene expression for the AhR and Nrf2 signal pathways. Experiments were performed on premature aging OXYS rats, which serve as a reliable model of age-related macular degeneration in humans. We studied the effect of melatonin on gene mRNA for the AhR and Nrf2 signal pathways. Melatonin was shown to decrease the level of mRNA for AhR-dependent genes of CYP1A2 and CYP1B1 cytochromes in the retina, but had no effect on the content of mRNA for Nrf2-dependent genes in OXYS rats.

  1. Protostellar Outflows

    NASA Astrophysics Data System (ADS)

    Bally, John

    2016-09-01

    Outflows from accreting, rotating, and magnetized systems are ubiquitous. Protostellar outflows can be observed from radio to X-ray wavelengths in the continuum and a multitude of spectral lines that probe a wide range of physical conditions, chemical phases, radial velocities, and proper motions. Wide-field visual and near-IR data, mid-IR observations from space, and aperture synthesis with centimeter- and millimeterwave interferometers are revolutionizing outflow studies. Many outflows originate in multiple systems and clusters. Although most flows are bipolar and some contain highly collimated jets, others are wide-angle winds, and a few are nearly isotropic and exhibit explosive behavior. Morphologies and velocity fields indicate variations in ejection velocity, mass-loss rate, and in some cases, flow orientation and degree of collimation. These trends indicate that stellar accretion is episodic and often occurs in a complex dynamical environment. Outflow power increases with source luminosity but decreases with evolutionary stage. The youngest outflows are small and best traced by molecules such as CO, SiO, H2O, and H2. Older outflows can grow to parsec scales and are best traced by shock-excited atoms and ions such as hydrogen-recombination lines, [Sii], and [Oii]. Outflows inject momentum and energy into their surroundings and provide an important mechanism in the self-regulation of star formation. However, momentum injection rates remain uncertain with estimates providing lower bounds.

  2. Wholemount imaging reveals abnormalities of the aqueous outflow pathway and corneal vascularity in Foxc1 and Bmp4 heterozygous mice.

    PubMed

    van der Merwe, Elizabeth L; Kidson, Susan H

    2016-05-01

    Mutations in the FOXC1/Foxc1 gene in humans and mice and Bmp4 in mice are associated with congenital anterior segment dysgenesis (ASD) and the development of the aqueous outflow structures throughout the limbus. The aim of this study was to advance our understanding of anterior segment abnormalities in mouse models of ASD using a 3-D imaging approach. Holistic imaging information combined with quantitative measurements were carried out on PECAM-1 stained individual components of the aqueous outflow vessels and corneal vasculature of Foxc1(+/-) on the C57BL/6Jx129 and ICR backgrounds, Bmp4(+/-) ICR mice, and wildtype mice from each background. In both wildtype and heterozygotes, singular, bifurcated and plexus forms of Schlemm's canal were noted. Of note, missing portions of the canal were seen in the heterozygous groups but not in wildtype animals. In general, we found the number of collector channels to be reduced in both heterozygotes. Lastly, we found a significant increase in the complexity of the corneal arcades and their penetration into the cornea in heterozygotes as compared with wild types. In conclusion, our 3-D imaging studies have revealed a more complex arrangement of both the aqueous vessels and corneal arcades in Foxc1(+/-) and Bmp4(+/-) heterozygotes, and further advance our understanding of how such abnormalities could impact on IOP and the aetiology of glaucoma.

  3. Wholemount imaging reveals abnormalities of the aqueous outflow pathway and corneal vascularity in Foxc1 and Bmp4 heterozygous mice.

    PubMed

    van der Merwe, Elizabeth L; Kidson, Susan H

    2016-05-01

    Mutations in the FOXC1/Foxc1 gene in humans and mice and Bmp4 in mice are associated with congenital anterior segment dysgenesis (ASD) and the development of the aqueous outflow structures throughout the limbus. The aim of this study was to advance our understanding of anterior segment abnormalities in mouse models of ASD using a 3-D imaging approach. Holistic imaging information combined with quantitative measurements were carried out on PECAM-1 stained individual components of the aqueous outflow vessels and corneal vasculature of Foxc1(+/-) on the C57BL/6Jx129 and ICR backgrounds, Bmp4(+/-) ICR mice, and wildtype mice from each background. In both wildtype and heterozygotes, singular, bifurcated and plexus forms of Schlemm's canal were noted. Of note, missing portions of the canal were seen in the heterozygous groups but not in wildtype animals. In general, we found the number of collector channels to be reduced in both heterozygotes. Lastly, we found a significant increase in the complexity of the corneal arcades and their penetration into the cornea in heterozygotes as compared with wild types. In conclusion, our 3-D imaging studies have revealed a more complex arrangement of both the aqueous vessels and corneal arcades in Foxc1(+/-) and Bmp4(+/-) heterozygotes, and further advance our understanding of how such abnormalities could impact on IOP and the aetiology of glaucoma. PMID:27068508

  4. KCa1.1 is potential marker for distinguishing Ah-type baroreceptor neurons in NTS and contributes to sex-specific presynaptic neurotransmission in baroreflex afferent pathway.

    PubMed

    Zhang, Yu-Yao; Yan, Zhen-Yu; Qu, Mei-Yu; Guo, Xin-Jing; Li, Guo; Lu, Xiao-Long; Liu, Yang; Ban, Tao; Sun, Hong-Li; Qiao, Guo-Fen; Li, Bai-Yan

    2015-09-14

    Sexual-dimorphic neurocontrol of circulation has been described in baroreflex due largely to the function of myelinated Ah-type baroreceptor neurons (BRNs, 1st-order) in nodose. However, it remains unclear if sex- and afferent-specific neurotransmission could also be observed in the central synapses within nucleus of solitary track (NTS, 2nd-order). According to the principle of no mixed neurotransmission among afferents and differentiation of Ah- and A-types to iberiotoxin (IbTX) observed in nodose, the 2nd-order Ah-type BRNs are highly expected. To test this hypothesis, the excitatory post-synaptic currents (EPSCs) were recorded in identified 2nd-order BRNs before and after IbTX using brain slice and whole-cell patch. These results showed that, in male rats, the dynamics of EPSCs in capsaicin-sensitive C-types were dramatically altered by IbTX, but not in capsaicin-insensitive A-types. Interestingly, near 50% capsaicin-insensitive neurons in females showed similar effects to C-types, suggesting the existence of Ah-types in NTS, which may be the likely reason why the females had lower blood pressure and higher sensitivity to aortic depressor nerve stimulation via KCa1.1-mediated presynaptic glutamate release from Ah-type afferent terminals.

  5. RNA interference targeting CYP76AH1 in hairy roots of Salvia miltiorrhiza reveals its key role in the biosynthetic pathway of tanshinones.

    PubMed

    Ma, Ying; Ma, Xiao-Hui; Meng, Fan-Yun; Zhan, Zhi-Lai; Guo, Juan; Huang, Lu-Qi

    2016-08-19

    Plant cytochrome P450s (CYPs) are well known as the largest family of enzymes that contribute to both primary metabolism and the chemical diversity of plant secondary metabolites. It is important to elucidate the in vivo role of CYPs in secondary metabolism, in order to apply them in the production of valuable metabolites in medicinal plants via metabolic engineering. CYP76AH1 has been suggested to catalyze the conversion of the carbon skeleton miltiradiene into the intermediate ferruginol, which is involved in the biosynthesis of tanshinones, the chief bioactive ingredients of Salvia miltiorrhiza. However, its role in planta remains to be elucidated. In this work, we constructed a CYP76AH1 RNAi system for hairy roots. Metabolic analysis of RNAi-AH1 hairy root lines showed a significantly increased accumulation of miltiradiene compared to the control lines. At the same time, the concentration of ferruginol decreased revealing the in vivo catalytic activity of CYP76AH1. The content of tanshinones decreased significantly after silencing of CYP76AH1, which verified its key role in the biosynthesis of tanshinones, and indicated that it could be used as a target for metabolic engineering. PMID:27291148

  6. Plant polyphenols differentially modulate inflammatory responses of human keratinocytes by interfering with activation of transcription factors NF{kappa}B and AhR and EGFR-ERK pathway

    SciTech Connect

    Potapovich, Alla I.; Lulli, Daniela; Fidanza, Paolo; Kostyuk, Vladimir A.; De Luca, Chiara; Pastore, Saveria; Korkina, Liudmila G.

    2011-09-01

    Molecular mechanisms underlying modulation of inflammatory responses in primary human keratinocytes by plant polyphenols (PPs), namely the glycosylated phenylpropanoid verbascoside, the stilbenoid resveratrol and its glycoside polydatin, and the flavonoid quercetin and its glycoside rutin were evaluated. As non-lethal stimuli, the prototypic ligand for epidermal growth factor receptor (EGFR) transforming growth factor alpha (TGFalpha), the combination of tumor necrosis factor (TNFalpha) and interferon (IFNgamma) (T/I), UVA + UVB irradiation, and bacterial lipopolysaccharide (LPS) were used. We demonstrated differential modulation of inflammatory responses in keratinocytes at signal transduction, gene transcription, and protein synthesis levels as a function of PP chemical structure, the pro-inflammatory trigger used, and PP interaction with intracellular detoxifying systems. The PPs remarkably inhibited constitutive, LPS- and T/I-induced but not TGFalpha-induced ERK phosphorylation. They also suppressed NFkappaB activation by LPS and T/I. Verbascoside and quercetin invariably impaired EGFR phosphorylation and UV-associated aryl hydrocarbon receptor (AhR)-mediated signaling, while rutin, polydatin and resveratrol did not affect EGFR phosphorylation and further activated AhR machinery in UV-exposed keratinocytes. In general, PPs down-regulated gene expression of pro-inflammatory cytokines/enzymes, except significant up-regulation of IL-8 observed under stimulation with TGFalpha. Both spontaneous and T/I-induced release of IL-8 and IP-10 was suppressed, although 50 {mu}M resveratrol and polydatin up-regulated IL-8. At this concentration, resveratrol activated both gene expression and de novo synthesis of IL-8 and AhR-mediated mechanisms were involved. We conclude that PPs differentially modulate the inflammatory response of human keratinocytes through distinct signal transduction pathways, including AhR and EGFR. - Graphical abstract: Display Omitted Highlights

  7. Newspapers and newspaper ink contain agonists for the ah receptor.

    PubMed

    Bohonowych, Jessica E S; Zhao, Bin; Timme-Laragy, Alicia; Jung, Dawoon; Di Giulio, Richard T; Denison, Michael S

    2008-04-01

    Ligand-dependent activation of the aryl hydrocarbon receptor (AhR) pathway leads to a diverse array of biological and toxicological effects. The best-studied ligands for the AhR include polycyclic and halogenated aromatic hydrocarbons, the most potent of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, as new AhR ligands are identified and characterized, their structural and physiochemical diversity continues to expand. Our identification of AhR agonists in crude extracts from diverse materials raises questions as to the magnitude and extent of human exposure to AhR ligands through normal daily activities. We have found that solvent extracts of newspapers from countries around the world stimulate the AhR signaling pathway. AhR agonist activity was observed for dimethyl sulfoxide (DMSO), ethanol, and water extracts of printed newspaper, unprinted virgin paper, and black printing ink, where activation of luciferase reporter gene expression was transient, suggesting that the AhR active chemical(s) was metabolically labile. DMSO and ethanol extracts also stimulated AhR transformation and DNA binding, and also competed with [(3)H]TCDD for binding to the AhR. In addition, DMSO extracts of printed newspaper induced cytochrome P450 1A associated 7-ethoxyresorufin-O-deethylase activity in zebrafish embryos in vivo. Although the responsible bioactive chemical(s) remain to be identified, our results demonstrate that newspapers and printing ink contain relatively potent metabolically labile agonists of the AhR. Given the large amount of recycling and reprocessing of newspapers throughout the world, release of these easily extractable AhR agonists into the environment should be examined and their potential effects on aquatic organisms assessed. PMID:18203687

  8. AH Her Observing Campaign

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2013-05-01

    Dr. Juan Echevarria (Universidad Nacional Autónoma de México) and colleagues request AAVSO assistance in a campaign on the Z Cam-type cataclysmic variable AH Her being carried out 2013 May 29 - June 18. They will be making photometric and spectroscopic observations of AH Her using the 2.1m and 0.84m telescopes at San Pedro Martir Observatory (SPM). Their goal is to carry out a radial velocity study of the system components using modern detectors; no study of AH Her has been made since the one by Horne, Wade, and Szkody in 1980-1981 (1986MNRAS.219..791H). Photometry and spectroscopy are requested. AH Her, for decades a reasonably "regular" Z Cam system, began exhibiting significantly anomalous behavior in ~2007. Since then it has experienced brief periods of fairly typical behavior interspersed with more anomalous intervals, including some unprecedented behavior. Most recently, it has returned to a more normal pattern of outbursts shape-wise but it is not back to its normal amplitude or frequency. AAVSO data will be essential for correlation in order to determine the precise time(s) of minimum occurring during the campaign. Finder charts with sequences may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.

  9. Functional Anatomy of the Outflow Facilities

    PubMed Central

    Pizzirani, Stefano; Gong, Haiyan

    2016-01-01

    The aqueous humor (AH) is the fluid that fills the anterior and posterior chambers of the eye. Its main roles are to provide nourishment and metabolic waste removal to active metabolic ocular structures that are avascular and to contribute maintaining a normal intraocular pressure (IOP) without altering the refractive status of the eye. Its composition and the fluid dynamics associated with its flow are voluble and undergo changes associated with age and disease. Of particular importance is that the resistance to the outflow of AH from the anterior chamber is influenced by morphologic, physiologic, and biochemical dynamic factors.1 Beside aqueous nutritional importance, its solutes also participate in establishing the anterior chamber associate immune deviation, and carry and distribute the different proteins and molecules that promote and direct tissue remodeling and changes in the anterior segment that are associated with both age and disease. PMID:26337760

  10. Endogenous Bioactive Lipids and the Regulation of Conventional Outflow Facility

    PubMed Central

    Wan, Zhou; Woodward, David F.; Stamer, W. Daniel

    2009-01-01

    Summary Perturbation of paracrine signaling within the human conventional outflow pathway influences tissue homeostasis and outflow function. For example, exogenous introduction of the bioactive lipids, sphingosine-1-phosphate, anandamide or prostaglandin F2α, to conventional outflow tissues alters the rate of drainage of aqueous humor through the trabecular meshwork, and into Schlemm’s canal. This review summarizes recent data that characterizes endogenous bioactive lipids, their receptors and associated signaling partners in the conventional outflow tract. We also discuss the potential of targeting such signaling pathways as a strategy for the development of therapeutics to treat ocular hypertension and glaucoma. PMID:19381354

  11. Size Distributions and Formation Pathways of Organic and Inorganic Constituents in Spring Aerosols from Okinawa Island in the Western North Pacific Rim: An Outflow Region of Asian Dusts

    NASA Astrophysics Data System (ADS)

    Deshmukh, D. K.; Lazaar, M.; Kawamura, K.; Kunwar, B.; Tachibana, E.; Boreddy, S. K. R.

    2015-12-01

    Size-segregated aerosols (9-stages) were collected at Okinawa Island in the western North Pacific Rim in spring 2008. The samples were analyzed for diacids (C2-C12), ω-oxoacids (ωC2-ωC9), a-dicarbonyls (C2-C3), organic carbon (OC), water-soluble OC (WSOC) and major ions to understand the sources and atmospheric processes in the outflow region of Asian pollutants. The molecular distribution of diacids showed the predominance of oxalic acid (C2) followed by malonic and succinic acids in all the size-segregated aerosols. ω-Oxoacids showed the predominance of glyoxylic acid (ωC2) whereas glyoxal (Gly) was more abundant than methylglyoxal in all the sizes. The abundant presence of sulfate as well as phthalic and adipic acids in Okinawa aerosols suggested a significant contribution of anthropogenic sources in East Asia via long-range atmospheric transport. Diacids (C2-C5), ωC2 and Gly as well as WSOC and OC peaked at 0.65-1.1 µm in fine mode whereas azelaic (C9) and 9-oxononanoic (ωC9) acids peaked at 3.3-4.7 µm in coarse mode. Sulfate and ammonium are enriched in fine mode whereas sodium and chloride are in coarse mode. An important mechanism for the formation of these organic species in Okinawa aerosols is probably gas phase oxidation of VOCs and subsequent in-cloud processing during long-range transport. Their characteristics size distribution implies that fine particles enriched with these organic and inorganic species could act as CCN to develop the cloud cover over the western North Pacific. The major peak of C9 and ωC9 on coarse mode suggest that they are produced by photooxidation of unsaturated fatty acids mainly derived from phytoplankton via heterogeneous reactions on sea spray particles. This study demonstrates that anthropogenic aerosols emitted from East Asia have significant influence on the compositions of organic and inorganic aerosols in the western North Pacific Rim.

  12. Directly Driven Ion Outflow

    NASA Technical Reports Server (NTRS)

    Elliott, H. A.; Comfort, R. H.; Craven, P. D.; Moore, T. E.; Russell, C. T.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    We examine ionospheric outflows in the high altitude magnetospheric polar cap during the POLAR satellite's apogee on April 19, 1996 using the Thermal Ion Dynamics Experiment (TIDE) instrument. The elevated levels of O(+) observed in this pass may be due to the geophysical conditions during and prior to the apogee pass. In addition to the high abundance of O(+) relative to H(+), several other aspects of this data are noteworthy. We observe relationships between the density, velocity, and temperature which appear to be associated with perpendicular heating and the mirror force, rather than adiabatic expansion. The H(+) outflow is at a fairly constant flux which is consistent with being source limited by charge exchange at lower altitudes. Local centrifugal acceleration in the polar cap is found to be insufficient to account for the main variations we observe in the outflow velocity. The solar wind speed is high during this pass approximately 700 kilometers per second, and there are Alfve'n waves present in the solar wind such that the solar wind speed and IMF Bx are correlated. In this pass both the H(+) and O(+) outflow velocities correlate with both the solar wind speed and IMF fluctuations. Polar cap magnetometer and Hydra electron data show the same long period wave structure as found in the solar wind and polar cap ion outflow. In addition, the polar cap Poynting flux along the magnetic field direction correlates well with the H(+) temperature (R=0.84). We conclude that the solar wind can drive polar cap ion outflow particularly during polar squalls by setting up a parallel drop that is tens of eV which then causes the ion outflow velocity of O(+) and H(+), the electrons, and magnetic perturbations to vary in a similar fashion.

  13. Outflow Propagation in Collapsars: Collimated Jets And Expanding Outflows

    SciTech Connect

    Mizuta, A.; Yamasaki, T.; Nagataki, S.; Mineshige, S.; /Kyoto U., Yukawa Inst., Kyoto /KIPAC, Menlo Park

    2007-06-08

    We investigate the outflow propagation in the collapsar in the context of gamma-ray bursts (GRBs) with 2D relativistic hydrodynamic simulations. We vary the specific internal energy and bulk Lorentz factor of the injected outflow from non-relativistic regime to relativistic one, fixing the power of the outflow to be 10{sup 51}erg s{sup -1}. We observed the collimated outflow, when the Lorentz factor of the injected outflow is roughly greater than 2. To the contrary, when the velocity of the injected outflow is slower, the expanding outflow is observed. The transition from collimated jet to expanding outflow continuously occurs by decreasing the injected velocity. Different features of the dynamics of the outflows would cause the difference between the GRBs and similar phenomena, such as, X-ray flashes.

  14. Studies of Quasar Outflows

    NASA Technical Reports Server (NTRS)

    Arav, Nahum

    2002-01-01

    The main aim of this research program is to determine the ionization equilibrium and abundances in quasar outflows. Especially in the broad absorption line QSO PG 0946+301. We find that the outflow's metalicity is consistent with being solar, while the abundance ratio of phosphorus to other metals is at least ten times solar. These findings are based on diagnostics that are not sensitive to saturation and partial covering effects in the BALs (Broad Adsorption Lines), which considerably weakened previous claims for enhanced metalicity. Ample evidence for these effects is seen in the spectrum.

  15. Metallicity and Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Wang, Huiyuan; Zhou, Hongyan; Yuan, Weimin; Wang, Tinggui

    2012-06-01

    Correlations of the outflow strength of quasars, as measured by the blueshift and asymmetry index (BAI) of the C IV line, with intensities and ratios of broad emission lines, based on composite quasar spectra built from the Sloan Digital Sky Survey, are investigated. We find that most of the line ratios of other ions to C IV increase prominently with BAI. These behaviors can be well understood in the context of increasing metallicity with BAI. The strength of the dominant coolant, C IV line, decreases, and weak collisionally excited lines increase with gas metallicity as a result of the competition between different line coolants. Using Si IV+O IV]/C IV as an indicator of gas metallicity, we present, for the first time, a strong correlation between the metallicity and the outflow strength of quasars over a wide range of 1.7-6.9 times solar abundance. Our result implies that metallicity plays an important role in the formation of quasar outflows, likely by affecting outflow acceleration. This effect may have a profound impact on galaxy evolution via momentum feedback and chemical enrichment.

  16. METALLICITY AND QUASAR OUTFLOWS

    SciTech Connect

    Wang, Huiyuan; Zhou, Hongyan; Wang, Tinggui; Yuan, Weimin

    2012-06-01

    Correlations of the outflow strength of quasars, as measured by the blueshift and asymmetry index (BAI) of the C IV line, with intensities and ratios of broad emission lines, based on composite quasar spectra built from the Sloan Digital Sky Survey, are investigated. We find that most of the line ratios of other ions to C IV increase prominently with BAI. These behaviors can be well understood in the context of increasing metallicity with BAI. The strength of the dominant coolant, C IV line, decreases, and weak collisionally excited lines increase with gas metallicity as a result of the competition between different line coolants. Using Si IV+O IV]/C IV as an indicator of gas metallicity, we present, for the first time, a strong correlation between the metallicity and the outflow strength of quasars over a wide range of 1.7-6.9 times solar abundance. Our result implies that metallicity plays an important role in the formation of quasar outflows, likely by affecting outflow acceleration. This effect may have a profound impact on galaxy evolution via momentum feedback and chemical enrichment.

  17. Simulation studies for wells AH-4bis/AH-17 and AH-18, Ahuachapan Geothermal Field

    SciTech Connect

    Monterrosa, Manuel Ernesto

    1996-01-24

    Well AH-4bis, at the Ahuachapan Geothermal Field is planned to be drilled on the same pad as the former AH-4. A simulation study was carried out for two casing dameters 13 5/8 and 9 5/8” in order to estimate its production and to know its economic feasibility. The simulation results indcate a high probability of production in the range of 7 Mwe, equivalent to 120 kg/s total mass flow rate, 1250 kJ/kg at 6 bar-a for the new well AH-4bis. Well AH- 17 is good producer, during 1991 after ten years of production, the well was shut-in due to silica scaling problems. A wellbore simulation was carried out in order to predict the new production conditions after the work-over, mainly to estimate the water flow rate in order to reduce the silica scaling. The results indicate a very low water flow rate. The match between the simulated and measured production curves after the work-over was successful. The well AH-18 is located at the southern part of the actual bore field. CEL is planning to expand the borefield at this area and it is neccessary to estimate the possible production condtions at that zone. The results indicate a high probabilty of production at that area. The power potential is estimated at 3.5 Mwe per well at WHP 6 bar-a and the wells will not require induction.

  18. Use of natural AhR ligands as potential therapeutic modalities against inflammatory disorders

    PubMed Central

    Busbee, Philip B; Rouse, Michael; Nagarkatti, Mitzi; Nagarkatti, Prakash S

    2014-01-01

    The aim of this review is to discuss research involving ligands for the aryl hydrocarbon receptor (AhR) and their role in immunomodulation. While activation of the AhR is well known for its ability to regulate the biochemical and toxic effects of environmental chemicals, more recently an exciting discovery has been made indicating that AhR ligation can also regulate T-cell differentiation, specifically through activation of Foxp3+ regulatory T cells (Tregs) and downregulation of the proinflammatory Th17 cells. Such findings have opened new avenues of research on the possibility of targeting the AhR to treat inflammatory and autoimmune diseases. Specifically, this review will discuss the current research involving natural and dietary AhR ligands. In addition, evidence indicating the potential use of these ligands in regulating inflammation in various diseases will be highlighted. The importance of the AhR in immunological processes can be illustrated by expression of this receptor on a majority of immune cell types. In addition, AhR signaling pathways have been reported to influence a number of genes responsible for mediating inflammation and other immune responses. As interest in the AhR and its ligands increases, it seems prudent to consolidate current research on the contributions of these ligands to immune regulation during the course of inflammatory diseases. PMID:23731446

  19. Particle Acceleration in Relativistic Outflows

    NASA Technical Reports Server (NTRS)

    Bykov, Andrei; Gehrels, Neil; Krawczynski, Henric; Lemoine, Martin; Pelletier, Guy; Pohl, Martin

    2012-01-01

    In this review we confront the current theoretical understanding of particle acceleration at relativistic outflows with recent observational results on various source classes thought to involve such outflows, e.g. gamma-ray bursts, active galactic nuclei, and pulsar wind nebulae. We highlight the possible contributions of these sources to ultra-high-energy cosmic rays.

  20. Zephyria Outflow Features

    NASA Technical Reports Server (NTRS)

    2004-01-01

    1 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows streamlined islands and a small cataract in an outflow channel system in the Zephyria region of Mars, south of Cerberus. The fluids responsible for creating these landforms flowed from the lower left (southwest) toward upper right (northeast). The fluids may have been water and mud or, some Mars scientists have argued, extremely fluid lava. The presence of a small cataract probably argues more strongly for a water and mud origin. This image is located near 3.8oN, 204.7oW. The picture covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from upper left.

  1. Ion Outflow Observations

    NASA Technical Reports Server (NTRS)

    Mellot, Mary (Technical Monitor)

    2002-01-01

    The characteristics of out-flowing ions have been investigated under various circumstances. In particular the upwelling of ions from the cleft region has been studied to attempt to look at source characteristics (e.g., temperature, altitude). High altitude (6-8 Re) data tend to show ions species that have the same velocity and are adiabatically cooled. Such ions, while representative of their source, can not provide an accurate picture. Ion observations from the TIDE detector on the Polar spacecraft show an energy (or equivalently a velocity) spectrum of ions as they undo the geomagnetic mass spectrometer effect due to convection-gravity separation of the different species. Consolidation of this type of data into a complete representation of the source spectrum can be attempted by building a set of maximum-phase-space- density-velocity pairs and attributing the total to the source.

  2. Absorbing Outflows in AGN

    NASA Technical Reports Server (NTRS)

    Mathur, Smita

    2002-01-01

    The goal of this program was a comprehensive multiwavelength study of absorption phenomena in active galactic nuclei (AGN). These include a variety of associated absorption systems: X-ray warm absorbers, X-ray cold absorbers. UV absorbers with high ionization lines, MgII absorbers, red quasars and BALQSOs. The aim is to determine the physical conditions in the absorbing outflows, study their inter-relations and their role in AGN. We designed several observing programs to achieve this goal: X-ray spectroscopy, UV spectroscopy, FLAY spectroscopy and X-ray imaging. We were very successful towards achieving the goal over the five year period as shown through following observing programs and papers. Copies of a few papers are attached with this report.

  3. RESULTS FROM THE AHS PESTICIDE EXPOSURE STUDY

    EPA Science Inventory

    The Agricultural Health Study/Pesticide Exposure Study (AHS/PES) measured exposures resulting from agricultural use of 2,4-D and chlorpyrifos for a subset of applicators in the AHS cohort. Through on-farm measurements and observations, data collected in the exposure study will...

  4. Cardiac outflow tract anomalies

    PubMed Central

    Neeb, Zachary; Lajiness, Jacquelyn D.; Bolanis, Esther; Conway, Simon J

    2014-01-01

    The mature outflow tract (OFT) is, in basic terms, a short conduit. It is a simple, although vital, connection situated between contracting muscular heart chambers and a vast embryonic vascular network. Unfortunately, it is also a focal point underlying many multifactorial congenital heart defects (CHDs). Through the use of various animal models combined with human genetic investigations, we are beginning to comprehend the molecular and cellular framework that controls OFT morphogenesis. Clear roles of neural crest cells (NCC) and second heart field (SHF) derivatives have been established during OFT formation and remodeling. The challenge now is to determine how the SHF and cardiac NCC interact, the complex reciprocal signaling that appears to be occurring at various stages of OFT morphogenesis, and finally how endocardial progenitors and primary heart field (PHF) communicate with both these colonizing extra-cardiac lineages. Although we are beginning to understand that this dance of progenitor populations is wonderfully intricate, the underlying pathogenesis and the spatiotemporal cell lineage interactions remain to be fully elucidated. What is now clear is that OFT alignment and septation are independent processes, invested via separate SHF and cardiac neural crest (CNC) lineages. This review will focus on our current understanding of the respective contributions of the SHF and CNC lineage during OFT development and pathogenesis. PMID:24014420

  5. AhR signalling and dioxin toxicity.

    PubMed

    Sorg, Olivier

    2014-10-15

    Dioxins are a family of molecules associated to several industrial accidents such as Ludwigshafen in 1953 or Seveso in 1976, to the Agent Orange used during the war of Vietnam, and more recently to the poisoning of the former president of Ukraine, Victor Yushchenko. These persistent organic pollutants are by-products of industrial activity and bind to an intracellular receptor, AhR, with a high potency. In humans, exposure to dioxins, in particular 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces a cutaneous syndrome known as chloracne, consisting in the development of many small skin lesions (hamartoma), lasting for 2-5 years. Although TCDD has been classified by the WHO as a human carcinogen, its carcinogenic potential to humans is not clearly demonstrated. It was first believed that AhR activation accounted for most, if not all, biological properties of dioxins. However, certain AhR agonists found in vegetables do not induce chloracne, and other chemicals, in particular certain therapeutic agents, may induce a chloracne-like syndrome without activating AhR. It is time to rethink the mechanism of dioxin toxicity and analyse in more details the biological events following exposure to these compounds and other AhR agonists, some of which have a very different chemical structure than TCDD. In particular various food-containing AhR agonists are non-toxic and may on the contrary have beneficial properties to human health. PMID:24239782

  6. Arylhydrocarbon receptor (AhR) activation in airway epithelial cells induces MUC5AC via reactive oxygen species (ROS) production.

    PubMed

    Chiba, Takahito; Uchi, Hiroshi; Tsuji, Gaku; Gondo, Hisaki; Moroi, Yoichi; Furue, Masutaka

    2011-02-01

    The dioxins and dioxin-like compounds in cigarette smoke regulate various immunological responses via the arylhydrocarbon receptor (AhR). These environmental toxicants are known to cause bronchitis, asthma, chronic obstructive pulmonary disease (COPD), and lung cancer. Recent studies have demonstrated that AhR activation upregulates the expression of mucin 5AC, oligomeric mucus/gel-forming (MUC5AC) in the airway epithelial cell line. However, the mechanism for the production of mucin has not been clarified. In this study, we investigated the role and pathway of AhR in airway epithelial cells by using selective agonists and antagonists. After stimulation with or without benzopyrene (B[a]P), an AhR agonist, MUC5AC expression was measured by real-time RT-PCR. The mechanism of AhR-induced MUC5AC expression in airway epithelial cells was studied in terms of the production of cytokine and reactive oxygen species (ROS). Treatment with B[a]P increased ROS generation in NCI-H₂₉₂ cells. Furthermore, B[a]P-induced MUC5AC upregulation and mucin production were inhibited by AhR siRNA or the use of an antioxidative agent. These results suggest that the AhR-induced increase of mucin production is partially mediated by ROS generation. An antioxidant therapy approach may help to cure AhR-induced mucus hypersecretory diseases. PMID:20709182

  7. Origin of outflows and winds

    NASA Technical Reports Server (NTRS)

    Koenigl, Arieh; Ruden, Steven P.

    1993-01-01

    Recent developments concerning the accretion-outflow connection and the role of magnetic fields are examined. It is argued that the weakly ionized wind most likely represents an MHD outflow driven centrifugally from the disk surfaces or from the boundary between the disk and the star. Specific wind models for each of these alternatives are presented, and it is contended that both provide a natural explanation of the observed correlation between accretion and outflow. The kinematic, thermal, and chemical wind properties predicted by these models are described and their observational implications are considered. It is suggested that the wind characteristics may be reflected in the observed forbidden line and IR continuum emission of T Tauri stars and in the measured abundances of various molecular species.

  8. Water in Shocks and Outflows

    NASA Astrophysics Data System (ADS)

    Neufeld, D. A.; Melnick, G. J.; Stauffer, J. R.; Ashby, M. L. N.; Bergin, E. A.; Kleiner, S. C.; Patten, B. M.; Plume, R.; Tolls, V.; Wang, Z.; Zhang, Y. F.; Goldsmith, P. F.; Harwit, M.; Erickson, N. R.; Howe, J. E.; Snell, R. L.; Koch, D. G.; Schieder, R.; Winnewisser, G.; Chin, G.

    1999-12-01

    We have observed water vapor emission from several protostellar outflow regions with SWAS, including the sources Orion-KL, NGC 2071, NGC 1333 IRAS 4, L1157, RCrA, and L1689N. Observations of the 110}-1{01 water transition toward each of these sources have revealed the presence of broad line emission accompanied by narrow absorption in quiescent foreground gas or -- in the case of Orion-KL, by a narrow emission line component. In each case, the width of the broad emission line component, typically 20 - 40 km s-1 (FWHM), suggests an origin in the outflowing gas. From the observed line fluxes, we estimate water abundances ranging from 10-6 in low mass outflow regions to several x 10-4 in the Orion-KL region. These values are all significantly larger than the water abundance estimates of few x 10-9 - 10-7 derived from SWAS observations of quiescent regions, implying that the water abundances are enhanced in outflow regions. Such enhancements are indeed expected to result from the effects of shocks in (1) vaporizing icy grain mantles and/or (2) producing water in the gas-phase (by means of neutral-neutral reactions that are negligibly slow at the low temperatures of quiescent clouds but rapid at the elevated temperatures present behind a shock.)

  9. Molecular outflows in starburst nuclei

    NASA Astrophysics Data System (ADS)

    Roy, Arpita; Nath, Biman B.; Sharma, Prateek; Shchekinov, Yuri

    2016-08-01

    Recent observations have detected molecular outflows in a few nearby starburst nuclei. We discuss the physical processes at work in such an environment in order to outline a scenario that can explain the observed parameters of the phenomenon, such as the molecular mass, speed and size of the outflows. We show that outflows triggered by OB associations, with NOB ≥ 105 (corresponding to a star formation rate (SFR)≥1 M⊙ yr-1 in the nuclear region), in a stratified disk with mid-plane density n0 ˜ 200-1000 cm-3 and scale height z0 ≥ 200(n0/102 cm-3)-3/5 pc, can form molecules in a cool dense and expanding shell. The associated molecular mass is ≥107 M⊙ at a distance of a few hundred pc, with a speed of several tens of km s-1. We show that a SFR surface density of 10 ≤ ΣSFR ≤ 50 M⊙ yr-1 kpc-2 favours the production of molecular outflows, consistent with observed values.

  10. The Geometry of Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib

    2012-10-01

    Quasar outflows are important for understanding the accretion and growth processes of the central black hole, but also potentially play a role in feedback to the galaxy, halting star formation and infall of gas. A big uncertainty lies in the geometry and density of these outflows, especially as a function of ionization and velocity. We aim to tackle this using the archival COS M grating spectra of 266 quasars. We separate the geometry of outflows into two parts: the solid angle subtended around the black hole, and the distance of the outflow from the central engine. Large numbers of quasars with high resolution spectra are required for each aspect of this statistical investigation. First, we will determine which/how many absorption-line systems are intrinsic through both partial covering methods and statistical assessments. Second, we will consider the incidence of intrinsic absorbers as a function of quasar property {e.g., radio-loudness, SED shape, black hole mass, bolometric luminosity}. This will reveal what determines the solid angle. This can only be done at moderate redshifts where quasars with a larger range of properties are observable, and hence requires HST/COS. Third, we will use the wide range of diagnostic lines to constrain the physical conditions of the absorbers. We will target the CIII*1175 complex and apply photoionization models to constrain the densities and ionization parameters. This will provide the largest set yet of intrinsic absorbers with systematic distance constraints. In tandem with the solid angles, this work will inform models regarding the geometry of quasar outflows.

  11. Hot outflows in galaxy clusters

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, C. C.; McNamara, B. R.

    2015-10-01

    The gas-phase metallicity distribution has been analysed for the hot atmospheres of 29 galaxy clusters using Chandra X-ray Observatory observations. All host brightest cluster galaxies (BCGs) with X-ray cavity systems produced by radio AGN. We find high elemental abundances projected preferentially along the cavities of 16 clusters. The metal-rich plasma was apparently lifted out of the BCGs with the rising X-ray cavities (bubbles) to altitudes between twenty and several hundred kiloparsecs. A relationship between the maximum projected altitude of the uplifted gas (the `iron radius') and jet power is found with the form R_Fe ∝ P_jet^{0.45}. The estimated outflow rates are typically tens of solar masses per year but exceed 100 M⊙ yr- 1 in the most powerful AGN. The outflow rates are 10-20 per cent of the cooling rates, and thus alone are unable to offset a cooling inflow. Nevertheless, hot outflows effectively redistribute the cooling gas and may play a significant role at regulating star formation and AGN activity in BCGs and presumably in giant elliptical galaxies. The metallicity distribution overall can be complex, perhaps due to metal-rich gas returning in circulation flows or being blown around in the hot atmospheres. Roughly 15 per cent of the work done by the cavities is expended lifting the metal-enriched gas, implying their nuclear black holes have increased in mass by at least ˜107-109 M⊙. Finally, we show that hot outflows can account for the broad, gas-phase metallicity distribution compared to the stellar light profiles of BCGs, and we consider a possible connection between hot outflows and cold molecular gas flows discovered in recent Atacama Large Millimeter Array observations.

  12. Pro-fibrotic pathway activation in trabecular meshwork and lamina cribrosa is the main driving force of glaucoma.

    PubMed

    Zhavoronkov, Alex; Kanherkar, Riya R; Izumchenko, Evgeny; Teka, Mahder; Cantor, Charles; Manaye, Kebreten; Sidransky, David; West, Michael D; Makarev, Eugene; Csoka, Antonei Benjamin

    2016-06-17

    While primary open-angle glaucoma (POAG) is a leading cause of blindness worldwide, it still does not have a clear mechanism that can explain all clinical cases of the disease. Elevated IOP is associated with increased accumulation of extracellular matrix (ECM) proteins in the trabecular meshwork (TM) that prevents normal outflow of aqueous humor (AH) and has damaging effects on the fine mesh-like lamina cribrosa (LC) through which the optic nerve fibers pass. Applying a pathway analysis algorithm, we discovered that an elevated level of TGFβ observed in glaucoma-affected tissues could lead to pro-fibrotic pathway activation in TM and in LC. In turn, activated pro-fibrotic pathways lead to ECM remodeling in TM and LC, making TM less efficient in AH drainage and making LC more susceptible to damage from elevated IOP via ECM transformation in LC. We propose pathway targets for potential therapeutic interventions to delay or avoid fibrosis initiation in TM and LC tissues. PMID:27229292

  13. Pro-fibrotic pathway activation in trabecular meshwork and lamina cribrosa is the main driving force of glaucoma

    PubMed Central

    Zhavoronkov, Alex; Izumchenko, Evgeny; Kanherkar, Riya R.; Teka, Mahder; Cantor, Charles; Manaye, Kebreten; Sidransky, David; West, Michael D.; Makarev, Eugene; Csoka, Antonei Benjamin

    2016-01-01

    ABSTRACT While primary open-angle glaucoma (POAG) is a leading cause of blindness worldwide, it still does not have a clear mechanism that can explain all clinical cases of the disease. Elevated IOP is associated with increased accumulation of extracellular matrix (ECM) proteins in the trabecular meshwork (TM) that prevents normal outflow of aqueous humor (AH) and has damaging effects on the fine mesh-like lamina cribrosa (LC) through which the optic nerve fibers pass. Applying a pathway analysis algorithm, we discovered that an elevated level of TGFβ observed in glaucoma-affected tissues could lead to pro-fibrotic pathway activation in TM and in LC. In turn, activated pro-fibrotic pathways lead to ECM remodeling in TM and LC, making TM less efficient in AH drainage and making LC more susceptible to damage from elevated IOP via ECM transformation in LC. We propose pathway targets for potential therapeutic interventions to delay or avoid fibrosis initiation in TM and LC tissues. PMID:27229292

  14. Quantitation of uveoscleral outflow in normotensive and glaucomatous Beagles by /sup 3/H-labeled dextran

    SciTech Connect

    Barrie, K.P.; Gum, G.G.; Samuelson, D.A.; Gelatt, K.N.

    1985-01-01

    In uveoscleral outflow, aqueous humor leaves the anterior chamber and passes caudally through the trabecular meshwork and the sclerociliary cleft to enter the supraciliary and suprachoroidal spaces. The fluid is then absorbed by choroidal and scleral circulations. Using /sup 3/H-labeled dextran, uveoscleral outflow was quantitated in normotensive and glaucomatous Beagles under general anesthesia. The intrascleral plexus was isolated and /sup 3/H-labeled dextran was injected into the anterior chamber. Intrascleral plexus contents were sampled every 5 minutes over a 30- to 60-minute period. The eyes were enucleated, sectioned, and prepared for scintillation counting. Uveoscleral outflow accounted for 15% and 3% of the total aqueous humor outflow in the normotensive dogs and in the advanced glaucomatous dogs, respectively. In the advanced glaucomatous Beagle, conventional and uveoscleral outflow pathways were reduced and contributed to the etiopathogenesis of glaucoma.

  15. Cerebrospinal fluid outflow along lumbar nerves and possible relevance for pain research: case report and review

    PubMed Central

    Bechter, Karl; Schmitz, Bernd

    2014-01-01

    CSF outflow through the cribriform plate near the olfactory nerves and the outflow along brain and spinal nerves are together known as peripheral CSF outflow pathway (PCOP). It is still not clear whether the PCOP has pathogenetic relevance. Our previous clinical observations have indicated that CSF may interact with nerves along the PCOP and in this article we present our finding of CSF outflow demonstrated by myelography in a single patient. We also discuss unexplained experimental pain pathomechanisms against the background of the PCOP hypothesis. We observed that CSF flowed along lumbar nerves in distal direction at a speed of about 10 cm per hour on its way through the tissues, mainly muscles. Total CSF outflow volume at the lumbar site was remarkable. CSF outflow at lumbar nerves was also documented by neuroradiology. It is plausible that CSF signaling serves for interaction with nerves along the PCOP, which could explain previously unknown pathomechanisms in pain generation. Experimental findings of tactile pain hypersensitivity within lumbosacral pain pathways could be explained by releasing of molecules, microparticles, or exosomes into the CSF by mast cells, which then move with CSF outflow along the PCOP and interact with nerves, initiating even retrograde synaptic stripping. PMID:25165054

  16. The immune phenotype of AhR null mouse mutants: not a simple mirror of xenobiotic receptor over-activation.

    PubMed

    Esser, Charlotte

    2009-02-15

    Intrinsic and induced cell differentiation and the cellular response to endogenous and exogenous signals are hallmarks of the immune system. Specific and common signalling cascades ensure a highly flexible and adapted response. Increasing evidence suggests that gene modulation by the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, is an important part of these processes. For decades the AhR has been studied mainly for its toxic effects after artificial activation by man-made chemical pollutants such as dioxins. These studies gave important, albeit to some extent skewed, evidence for a mechanistic link between the AhR and the immune system. AhR null mutants and other mutants of the AhR signalling pathway have been generated and used to analyse the physiological function of the AhR, including for the developing and antigen-responding immune system. In this review I look at the natural immunological function(s) of the AhR.

  17. Aqueous outflow: Segmental and distal flow

    PubMed Central

    Swaminathan, Swarup S.; Oh, Dong-Jin; Kang, Min Hyung; Rhee, Douglas J.

    2014-01-01

    A prominent risk factor of primary open-angle glaucoma is ocular hypertension, a pathologic state caused by impaired outflow of aqueous humor through the trabecular meshwork within the iridocorneal angle. The juxtacanalicular region of the trabecular meshwork and the inner wall of Schlemm canal have been identified as the main contributors to aqueous outflow resistance, and both extracellular matrix within the trabecular meshwork and trabecular meshwork cell shape have been shown to affect outflow. Overexpression of multiple ECM proteins in perfused cadaveric human eyes has led to increased outflow resistance and elevated IOP. Pharmacologic agents targeting trabecular meshwork cytoskeletal arrangements have been developed after multiple studies demonstrated the importance of cell shape on outflow. Several groups have shown that aqueous outflow occurs only at certain segments of the trabecular meshwork circumferentially, a concept known as segmental flow. This is based on the theory that aqueous outflow is dependent on the presence of discrete pores within the Schlemm canal. Segmental flow has been described in the eyes of multiple species, including primate, bovine, mouse, and human samples. While the trabecular meshwork appears to be the major source of resistance, trabecular meshwork bypass procedures have been unable to achieve the degree of IOP reduction observed with trabeculectomy, reflecting the potential impact of distal flow, or flow through Schlemm canal and collector channels, on outflow. Multiple studies have demonstrated that outflow occurs preferentially near collector channels, suggesting that these distal structures may be more important to aqueous outflow than previously believed. PMID:25088623

  18. Control of outflow resistance by soluble adenylyl cyclase.

    PubMed

    Lee, Yong Suk; Marmorstein, Alan D

    2014-01-01

    Abstract Glaucoma is a leading cause of blindness in the United States affecting as many as 2.2 million Americans. All current glaucoma treatment strategies aim to reduce intraocular pressure, even in patients with normal tension glaucoma. Typically, this is accomplished by reducing the rate of aqueous flow by limiting aqueous production or enhancing drainage using drugs and surgery. Whereas these strategies are effective in diminishing vision loss, some patients continue to lose vision and many discontinue use of their medications because of undesirable side effects. Drugs known to be effective in altering conventional outflow have for the most part been abandoned from modern clinical practice due to undesirable side effects. Identification of new drugs that could enhance conventional outflow, would offer additional options in the treatment of glaucoma and ocular hypertension. To this end, our laboratory has recently uncovered a novel pathway for regulation of conventional outflow by the ciliary body. This pathway is dependent on soluble adenylyl cyclase, an enzyme that catalyzes the generation of cyclic adenosine 3',5' monophosphate (cAMP) in response to bicarbonate.

  19. 12 CFR Appendixes A-H to Subpart A... - Appendixes A-H to Subpart A of Part 702

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Appendixes A-H to Subpart A of Part 702 A Appendixes A-H to Subpart A of Part 702 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PROMPT CORRECTIVE ACTION Net Worth Classification Pt. 702, Apps. Appendixes A-H...

  20. 12 CFR Appendixes A-H to Subpart A... - Appendixes A-H to Subpart A of Part 702

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Appendixes A-H to Subpart A of Part 702 A Appendixes A-H to Subpart A of Part 702 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PROMPT CORRECTIVE ACTION Net Worth Classification Pt. 702, Apps. Appendixes A-H...

  1. 12 CFR Appendixes A-H to Subpart A... - Appendixes A-H to Subpart A of Part 702

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Appendixes A-H to Subpart A of Part 702 A Appendixes A-H to Subpart A of Part 702 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PROMPT CORRECTIVE ACTION Net Worth Classification Pt. 702, Apps. Appendixes A-H...

  2. 12 CFR Appendixes A-H to Subpart A... - Appendixes A-H to Subpart A of Part 702

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Appendixes A-H to Subpart A of Part 702 A Appendixes A-H to Subpart A of Part 702 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PROMPT CORRECTIVE ACTION Net Worth Classification Pt. 702, Apps. Appendixes A-H...

  3. 12 CFR Appendixes A-H to Subpart A... - Appendixes A-H to Subpart A of Part 702

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Appendixes A-H to Subpart A of Part 702 A Appendixes A-H to Subpart A of Part 702 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PROMPT CORRECTIVE ACTION Net Worth Classification Pt. 702, Apps. Appendixes A-H...

  4. OUTFLOWS IN SODIUM EXCESS OBJECTS

    SciTech Connect

    Park, Jongwon; Yi, Sukyoung K.; Jeong, Hyunjin

    2015-08-10

    Van Dokkum and Conroy revisited the unexpectedly strong Na i lines at 8200 Å found in some giant elliptical galaxies and interpreted them as evidence for an unusually bottom-heavy initial mass function. Jeong et al. later found a large population of galaxies showing equally extraordinary Na D doublet absorption lines at 5900 Å (Na D excess objects: NEOs) and showed that their origins can be different for different types of galaxies. While a Na D excess seems to be related to the interstellar medium (ISM) in late-type galaxies, smooth-looking early-type NEOs show little or no dust extinction and hence no compelling signs of ISM contributions. To further test this finding, we measured the Doppler components in the Na D lines. We hypothesized that the ISM would have a better (albeit not definite) chance of showing a blueshift Doppler departure from the bulk of the stellar population due to outflow caused by either star formation or AGN activities. Many of the late-type NEOs clearly show blueshift in their Na D lines, which is consistent with the former interpretation that the Na D excess found in them is related to gas outflow caused by star formation. On the contrary, smooth-looking early-type NEOs do not show any notable Doppler components, which is also consistent with the interpretation of Jeong et al. that the Na D excess in early-type NEOs is likely not related to ISM activities but is purely stellar in origin.

  5. Inhibition of constitutive aryl hydrocarbon receptor (AhR) signaling attenuates androgen independent signaling and growth in (C4-2) prostate cancer cells

    PubMed Central

    Tran, Cindy; Richmond, Oliver; Aaron, LaTayia; Powell, Joann B.

    2013-01-01

    The aryl hydrocarbon receptor is a member of the basic-helix-loop-helix family of transcription factors. AhR mediates the biochemical and toxic effects of a number of polyaromatic hydrocarbons such as 2,3,7,8,-tetrachloro-dibenzo-p-dioxin (TCDD). AhR is widely known for regulating the transcription of drug metabolizing enzymes involved in the xenobiotic metabolism of carcinogens and therapeutic agents, such as cytochrome P450-1B1 (CYP1B1). Additionally, AhR has also been reported to interact with multiple signaling pathways during prostate development. Here we investigate the effect of sustained AhR signaling on androgen receptor function in prostate cancer cells. Immunoblot analysis shows that AhR expression is increased in androgen independent (C4-2) prostate cancer cells when compared to androgen sensitive (LNCaP) cells. RT-PCR studies revealed constitutive AhR signaling in C4-2 cells without the ligand induced activation required in LNCaP cells. A reduction of AhR activity by short RNA mediated silencing in C4-2 cells reduced expression of both AhR and androgen responsive genes. The decrease in androgen responsive genes correlates to a decrease in phosphorylated androgen receptor and androgen receptor expression in the nucleus. Furthermore, the forced decrease in AhR expression resulted in a 50% decline in the growth rate of C4-2 cells. These data indicates that AhR is required to maintain hormone independent signaling and growth by the androgen receptor in C4-2 cells. Collectively, these data provide evidence of a direct role for AhR in androgen independent signaling and provides insight into the molecular mechanisms responsible for sustained androgen receptor signaling in hormone refractory prostate cancer. PMID:23266674

  6. Bright crater outflows: Possible emplacement mechanisms

    NASA Technical Reports Server (NTRS)

    Chadwick, D. John; Schaber, Gerald G.; Strom, Robert G.; Duval, Darla M.

    1992-01-01

    Lobate features with a strong backscatter are associated with 43 percent of the impact craters cataloged in Magellan's cycle 1. Their apparent thinness and great lengths are consistent with a low-viscosity material. The longest outflow yet identified is about 600 km in length and flows from the 90-km-diameter crater Addams. There is strong evidence that the outflows are largely composed of impact melt, although the mechanisms of their emplacement are not clearly understood. High temperatures and pressures of target rocks on Venus allow for more melt to be produced than on other terrestrial planets because lower shock pressures are required for melting. The percentage of impact craters with outflows increases with increasing crater diameter. The mean diameter of craters without outflows is 14.4 km, compared with 27.8 km for craters with outflows. No craters smaller than 3 km, 43 percent of craters in the 10- to 30-km-diameter range, and 90 percent in the 80- to 100-km-diameter range have associated bright outflows. More melt is produced in the more energetic impact events that produce larger craters. However, three of the four largest craters have no outflows. We present four possible mechanisms for the emplacement of bright outflows. We believe this 'shotgun' approach is justified because all four mechanisms may indeed have operated to some degree.

  7. Gene expression analysis in children with complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis.

    PubMed

    Tsuge, Mitsuru; Oka, Takashi; Yamashita, Nobuko; Saito, Yukie; Fujii, Yosuke; Nagaoka, Yoshiharu; Yashiro, Masato; Tsukahara, Hirokazu; Morishima, Tsuneo

    2014-02-01

    Viral infections have been implicated as a cause of complex seizures in children. The pathogenic differences in complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis remain unclear. This study analyzed the gene expression profiles in the peripheral whole blood from pediatric patients with complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis. The gene expression profiles of ten patients (five with seizures and five without) with influenza A(H1N1)pdm09 and six patients (three with seizures and three without) with rotavirus gastroenteritis were examined. Gene expression profiles in the whole blood were different in complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis. Transcripts related to the immune response were significantly differentially expressed in complex seizures with influenza A(H1N1)pdm09, and transcripts related to the stress response were significantly differentially expressed in complex seizures with rotavirus gastroenteritis. Pathway analysis showed that the mitogen-activated protein kinases in the T cell receptor signaling pathway were activated in complex seizures due to influenza A(H1N1)pdm09. Dysregulation of the genes related to immune response or stress response could contribute to the pathogenic differences of the complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis.

  8. Molecular and Chemical Analysis of the Lipopolysaccharide from Aeromonas hydrophila Strain AH-1 (Serotype O11)

    PubMed Central

    Merino, Susana; Canals, Rocío; Knirel, Yuriy A.; Tomás, Juan M.

    2015-01-01

    A group of virulent Aeromonas hydrophila, A. sobria, and A. veronii biovar sobria strains isolated from humans and fish have been described; these strains classified to serotype O11 are serologically related by their lipopolysaccharide (LPS) O-antigen (O-polysaccharide), and the presence of an S-layer consisting of multiple copies of a crystalline surface array protein with a molecular weight of 52 kDa in the form of a crystalline surface array which lies peripheral to the cell wall. A. hydrophila strain AH-1 is one of them. We isolated the LPS from this strain and determined the structure of the O-polysaccharide, which was similar to that previously described for another strain of serotype O11. The genetics of the O11-antigen showed the genes (wbO11 cluster) in two sections separated by genes involved in biosynthesis and assembly of the S-layer. The O11-antigen LPS is an example of an ABC-2-transporter-dependent pathway for O-antigen heteropolysaccharide (disaccharide) assembly. The genes involved in the biosynthesis of the LPS core (waaO11 cluster) were also identified in three different chromosome regions being nearly identical to the ones described for A. hydrophila AH-3 (serotype O34). The genetic data and preliminary chemical analysis indicated that the LPS core for strain AH-1 is identical to the one for strain AH-3. PMID:25874921

  9. RNA polymerase II cofactor PC2 facilitates activation of transcription by GAL4-AH in vitro.

    PubMed Central

    Kretzschmar, M; Stelzer, G; Roeder, R G; Meisterernst, M

    1994-01-01

    We have isolated from a crude Hela cell cofactor fraction (USA) a novel positive cofactor that cooperates with the general transcription machinery to effect efficient stimulation of transcription by GAL4-AH, a derivative of the Saccharomyces cerevisiae regulatory factor GAL4. PC2 was shown to be a 500-kDa protein complex and to be functionally and biochemically distinct from native TFIID and previously identified cofactors. In the presence of native TFIID and other general factors, PC2 was necessary and sufficient for activation by GAL4-AH. Cofactor function was specific for transcriptional activation domains of GAL4-AH. The repressor histone H1 further potentiated but was not required for activation of transcription by GAL4-AH. On the basis of the observation that PC2 exerts entirely positive effects on transcription, we propose a model in which PC2 increases the activity of the preinitiation complex in the presence of an activator, thereby establishing a specific pathway during activation of RNA polymerase II. Images PMID:8196633

  10. Magnetospheric Sawtooth Oscillations Induced by Ionospheric Outflow

    NASA Astrophysics Data System (ADS)

    Brambles, O. J.; Lotko, W.; Zhang, B.; Lyon, J.; Wiltberger, M. J.

    2010-12-01

    This paper aims to address why sawtooth oscillations occur and what factors affect their periodicity. We use a multifluid version of the LFM global simulation model, driven by a steady solar wind to examine the effects of ion outflow on convection in the magnetosphere. In the simulation model, the properties of cusp and auroral region O+ outflow are causally regulated by electron precipitation and electromagnetic power flowing into the ionosphere. It is found that when ion outflow is included in the simulation, the solar wind-magnetosphere-ionosphere interaction can generate periodic substorms which appear as sawtooth-like oscillations in the geostationary magnetic field. The ion outflow enhances plasma pressure in the inner magnetosphere and the associated diamagnetic ring current stretches the field lines throughout the nightside, essentially from dawn to dusk. If the field lines are sufficiently stretched they reconnect and dipolarize, ejecting a plasmoid downtail. This cycle repeats forming multiple sawtooth oscillations. The periodicity of the sawtooth oscillation depends largely upon the strength of the outflow. The strength of outflow is varied in the simulation by changing both the driving conditions (which affects the power flowing into the ionosphere) and through direct modification of the constants in the empirical relationships. Higher outflow fluences produce oscillations with shorter periods. The period of the oscillation is found to vary in the simulations from approximately 2 hours to 6 hours depending upon the strength of the outflow. For a smaller solar wind electric field the outflow fluence is not large enough to stretch the nightside field lines enough for sawtooth oscillations to form and the magnetosphere goes into a steady magnetosphere convection (SMC) mode. As the solar wind electric field increases the outflow fluence becomes sufficiently large to affect the convection in the magnetosphere and generate sawtooth oscillations. The strength

  11. Ah receptor ligands in tobacco smoke.

    PubMed

    Löfroth, G; Rannug, A

    1988-08-01

    Tar particulates from cigarette smoke contain compounds with affinity for the Ah receptor. The sidestream activity is larger than that of the mainstream with a ratio of about 5. The compounds causing the affinity appear in the neutral fraction after chemical fractionation excluding basic and acidic components as major contributors to the affinity. The affinity cannot be explained by benzo[a]pyrene and other polycyclic aromatic hydrocarbons but it might be caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds and by oxidized tryptophan derivatives.

  12. The resolved outflow from 3C 48

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan E-mail: stockton@ifa.hawaii.edu

    2014-10-20

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 10{sup 3}-10{sup 4} cm{sup –3}, the mass is ∼6 × 10{sup 6} M {sub ☉}, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow.

  13. AH Leo and the Blazhko Effect

    NASA Astrophysics Data System (ADS)

    Phillips, J.; Gay, P. L.

    2004-12-01

    We obtained 563 V-Band observations of AH Leo between January 27 and May 12, 2004. All observations were obtained with a 12-inch Schmidt-Cassegrain located on the island of Saipan, in the Commonwealth of the Northern Mariana Islands. We show that AH Leo is a type RRab RR Lyrae star with a minimum magnitude of V=14.658 magnitudes, a maximum amplitude of 0.989 magnitudes and a minimum amplitude of perhaps just 0.4 magnitudes. Its primary period is 0.4662609 days. Our observations also confirm the presence of the Blazhko effect, which had previously been detected by Smith and Gay (private communication) in 1993 and 1994. We estimate the Blazhko period to be roughly 20-days, however poor phase coverage at maximum light makes exact determination impossible. We also note that the bump during minimum, which is common in many RR Lyraes, varied throughout the Blazhko cycle, demonstrating amplitudes between 0 and 0.15 magnitudes. We would like to thank Sarah Maddison and Swinburne Astronomy Online for supporting this project

  14. Testing Update on 20 and 25-Ah Lithium Ion Cells

    NASA Technical Reports Server (NTRS)

    Bruce, Gregg C.; Mardikian, Pamella; Edwards, Sherri; Bugga, Kumar; Chin, Keith; Smart, Marshall; Surampudi, Subbarao

    2003-01-01

    Eagle-Picher Energy Products has worked on lithium ion batteries for approximately 8 years. During that period EPEPC developed and delivered several cell sizes on a program funded by the USAF and Canadian DND. Designs are wound cylindrical cells from 7 to 40-Ah. Most cells delivered were approximately 25-Ah due to requirements of Mars missions. Several iterations of cells were manufactured and delivered for evaluation. The first design was 20-Ah, Design I, and the second was a 25-Ah, Design II.

  15. Theory of MHD Jets and Outflows

    NASA Astrophysics Data System (ADS)

    Tsinganos, Kanaris

    A brief review is given of selected results of our analytical and numerical work on the construction of time-independent and time-dependent MHD models for non relativistic astrophysical outflows and jets. The equations for steady MHD plasma flows are first outlined. Next, 1-D spherically symmetric outflows are briefly discussed, namely the Parker thermally driven nonrotating wind, as the classical prototype of all astrophysical outflows and the Weber-Davis magnetocentrifugally driven wind together with its astrophysical implications for magnetic braking, etc. Then, we turn to the 2-D MHD problem for steady and non steady 2-D axisymmetric magnetized and rotating plasma outflows. The only available exact solutions for such outflows are those in separable coordinates, i.e. those with the symmetry of radial or meridional self-similarity. Physically accepted solutions pass from the fast magnetosonic separatrix surface in order to satisfy MHD causality. An energetic criterion is outlined for selecting radially expanding winds from cylindrically expanding jets. The basics of jet acceleration, collimation, minimum fieldline inclination and angular momentum removal are illustrated in the context of radially self similar models. Numerical simulations of magnetic self-collimation verify several results of analytical steady solutions. The outflow from solar-type inefficient magnetic rotators is very weakly collimated while that from a ten times faster rotating YSO produces a tightly collimated jet. We also propose a two-component model consisting of a wind outflow from the central object and a faster rotating outflow launched from the surrounding accretion disk which plays the role of the flow collimator. We also briefly discuss the problem of shock formation during the magnetic collimation of wind-type outflows into jets.

  16. Metal enrichment of the CGM through outflows

    NASA Astrophysics Data System (ADS)

    Christensen, Charlotte

    2016-01-01

    Galactic outflows enrich the circumgalactic medium through the redistribution of metals from the disks of galaxies. We examine the history of this enrichment by analyzing the outflows of twenty high-resolution simulated galaxies spanning two and a half orders of magnitude in halo mass. These simulations match many observed trends, including the mass-metallicity relation. By tracking particles in the simulations, we follow the removal and reaccretion of metals between redshift 3.5 and 0. We also determine the enrichment of the outflowing gas compared to the local interstellar media. Finally we compare the redshift zero metal census to observed values.

  17. Outflows in Sodium Excess Objects

    NASA Astrophysics Data System (ADS)

    Park, Jongwon; Jeong, Hyunjin; Yi, Sukyoung

    2016-01-01

    van Dokkum and Conroy reported that some giant elliptical galaxies show extraordinarily strong Na I absorption lines and suggested that this is the evidence of unusually bottom-heavy initial mass function. Jeong et al. later studied galaxies with unexpectedly strong Na D absorption lines (Na D excess objects: NEOs) and showed that the origins of NEOs are different for different types of galaxies. According to their study, the origin of Na D excess seems to be related to interstellar medium (ISM) in late-type galaxies, but there seems to be no contributions from ISM in smooth-looking early-type galaxies. In order to test this finding, we measured the Doppler components in Na D lines of NEOs. We hypothesized that if Na D absorption line is related to ISM, the absorption line is more likely to be blueshifted in the spectrum by the motion of ISM caused by outflow. Many of late-type NEOs show blueshifted Na D absorption lines, so their origin seems related to ISM. On the other hand, smooth-looking early-type NEOs do not show Doppler departure and Na D excess in early-type NEOs is likely not related to ISM, which is consistent with the finding of Jeong et al.

  18. MEF2C regulates outflow tract alignment and transcriptional control of Tdgf1.

    PubMed

    Barnes, Ralston M; Harris, Ian S; Jaehnig, Eric J; Sauls, Kimberly; Sinha, Tanvi; Rojas, Anabel; Schachterle, William; McCulley, David J; Norris, Russell A; Black, Brian L

    2016-03-01

    Congenital heart defects are the most common birth defects in humans, and those that affect the proper alignment of the outflow tracts and septation of the ventricles are a highly significant cause of morbidity and mortality in infants. A late differentiating population of cardiac progenitors, referred to as the anterior second heart field (AHF), gives rise to the outflow tract and the majority of the right ventricle and provides an embryological context for understanding cardiac outflow tract alignment and membranous ventricular septal defects. However, the transcriptional pathways controlling AHF development and their roles in congenital heart defects remain incompletely elucidated. Here, we inactivated the gene encoding the transcription factor MEF2C in the AHF in mice. Loss of Mef2c function in the AHF results in a spectrum of outflow tract alignment defects ranging from overriding aorta to double-outlet right ventricle and dextro-transposition of the great arteries. We identify Tdgf1, which encodes a Nodal co-receptor (also known as Cripto), as a direct transcriptional target of MEF2C in the outflow tract via an AHF-restricted Tdgf1 enhancer. Importantly, both the MEF2C and TDGF1 genes are associated with congenital heart defects in humans. Thus, these studies establish a direct transcriptional pathway between the core cardiac transcription factor MEF2C and the human congenital heart disease gene TDGF1. Moreover, we found a range of outflow tract alignment defects resulting from a single genetic lesion, supporting the idea that AHF-derived outflow tract alignment defects may constitute an embryological spectrum rather than distinct anomalies. PMID:26811383

  19. Magnetosphere sawtooth oscillations induced by ionospheric outflow.

    PubMed

    Brambles, O J; Lotko, W; Zhang, B; Wiltberger, M; Lyon, J; Strangeway, R J

    2011-06-01

    The sawtooth mode of convection of Earth's magnetosphere is a 2- to 4-hour planetary-scale oscillation powered by the solar wind-magnetosphere-ionosphere (SW-M-I) interaction. Using global simulations of geospace, we have shown that ionospheric O(+) outflows can generate sawtooth oscillations. As the outflowing ions fill the inner magnetosphere, their pressure distends the nightside magnetic field. When the outflow fluence exceeds a threshold, magnetic field tension cannot confine the accumulating fluid; an O(+)-rich plasmoid is ejected, and the field dipolarizes. Below the threshold, the magnetosphere undergoes quasi-steady convection. Repetition and the sawtooth period are controlled by the strength of the SW-M-I interaction, which regulates the outflow fluence. PMID:21636770

  20. Magnetosphere sawtooth oscillations induced by ionospheric outflow.

    PubMed

    Brambles, O J; Lotko, W; Zhang, B; Wiltberger, M; Lyon, J; Strangeway, R J

    2011-06-01

    The sawtooth mode of convection of Earth's magnetosphere is a 2- to 4-hour planetary-scale oscillation powered by the solar wind-magnetosphere-ionosphere (SW-M-I) interaction. Using global simulations of geospace, we have shown that ionospheric O(+) outflows can generate sawtooth oscillations. As the outflowing ions fill the inner magnetosphere, their pressure distends the nightside magnetic field. When the outflow fluence exceeds a threshold, magnetic field tension cannot confine the accumulating fluid; an O(+)-rich plasmoid is ejected, and the field dipolarizes. Below the threshold, the magnetosphere undergoes quasi-steady convection. Repetition and the sawtooth period are controlled by the strength of the SW-M-I interaction, which regulates the outflow fluence.

  1. Powerful Molecular Outflows in Nearby Active Galaxies

    NASA Astrophysics Data System (ADS)

    Veilleux, Sylvain; Meléndez, Marcio

    2014-07-01

    We report the results from a systematic search for molecular (OH 119 μm) outflows with Herschel-PACS† in a sample of 43 nearby (z < 0.3) galaxy mergers, mostly ultraluminous infrared galaxies (ULIRGs) and QSOs. We find that the character of the OH feature (strength of the absorption relative to the emission) correlates with that of the 9.7-μm silicate feature, a measure of obscuration in ULIRGs. Unambiguous evidence for molecular outflows, based on the detection of OH absorption profiles with median velocities more blueshifted than -50 km s-1, is seen in 26 (70%) of the 37 OH-detected targets, suggesting a wide-angle (~ 145°) outflow geometry. Conversely, unambiguous evidence for molecular inflows, based on the detection of OH absorption profiles with median velocities more redshifted than +50 km s-1, is seen in only 4 objects, suggesting a planar or filamentary geometry for the inflowing gas. Terminal outflow velocities of ~ -1000 km s-1 are measured in several objects, but median outflow velocities are typically ~ -200 km s-1. While the outflow velocities show no statistically significant dependence on the star formation rate, they are distinctly more blueshifted among systems with large AGN fractions and luminosities [log (L AGN/L ⊙) >= 11.8 +/- 0.3]. The quasars in these systems play a dominant role in driving the molecular outflows. In contrast, the most AGN dominated systems, where OH is seen purely in emission, show relatively modest OH line widths, despite their large AGN luminosities, perhaps indicating that molecular outflows subside once the quasar has cleared a path through the obscuring material.

  2. Lactobacillus bulgaricus OLL1181 activates the aryl hydrocarbon receptor pathway and inhibits colitis.

    PubMed

    Takamura, Takeyuki; Harama, Daisuke; Fukumoto, Suguru; Nakamura, Yuki; Shimokawa, Naomi; Ishimaru, Kayoko; Ikegami, Shuji; Makino, Seiya; Kitamura, Masanori; Nakao, Atsuhito

    2011-10-01

    Increasing evidence suggests that the aryl hydrocarbon receptor (AhR) pathway has an important role in the regulation of inflammatory responses. Most recently, we have shown that the activation of the AhR pathway by a potent AhR agonist inhibits the development of dextran sodium sulfate (DSS)-induced colitis, a model of human ulcerative colitis, by the induction of prostaglandin E2 (PGE2) in the large intestine. Because several strains of probiotic lactic acid bacteria have been reported to inhibit DSS-induced colitis by unidentified mechanisms, we hypothesized that particular strains of lactic acid bacterium might have the potential to activate the AhR pathway, thereby inhibiting DSS-induced colitis. This study investigated whether there are specific lactic acid bacterial strains that can activate the AhR pathway, and if so, whether this AhR-activating potential is associated with suppression of DSS-induced colitis. By using AhR signaling reporter cells, we found that Lactobacillus bulgaricus OLL1181 had the potential to activate the AhR pathway. OLL1181 also induced the mRNA expression of cytochrome P450 family 1A1 (CYP1A1), a target gene of the AhR pathway, in human colon cells, which was inhibited by the addition of an AhR antagonist, α-naphthoflavon (αNF). In addition, mice treated orally with OLL1181 showed an increase in CYP1A1 mRNA expression in the large intestine and amelioration of DSS-induced colitis. Thus, OLL1181 can induce activation of the intestinal AhR pathway and inhibit DSS-induced colitis in mice. This strain of lactic acid bacterium has therefore the potential to activate the AhR pathway, which may be able to suppress colitis.

  3. Performance of AEA 80 Ah Battery under GEO Profiles

    NASA Technical Reports Server (NTRS)

    Russel, N.; Curzon, D.; Ng, K.; Lee, L.; Rao, G.

    2004-01-01

    This viewgraph presentation is divided into the following sections: 1) AEA Geosynchronous Earth Orbit (GEO) Life Testing; 2) AEA/Goddard Space Flight Center (GSFC) 20 Ah Battery; 3) AEA/GSFC 80 Ah Battery; 4) Solar Dynamic Observatory (SDO) Life Test; 5) Test Results; 6) Correlation; 7) Conclusions.

  4. Induction of AhR-Mediated Gene Transcription by Coffee

    PubMed Central

    Ishikawa, Toshio; Takahashi, Satoshi; Morita, Koji; Okinaga, Hiroko; Teramoto, Tamio

    2014-01-01

    Background Aryl hydrocarbon receptor (AhR) is classically known to be activated by xenobiotics such as dioxins and polycyclic aromatic hydrocarbons (PAHs). Although it has been reported that PAHs are contained in roasted coffee beans, in general coffee beverages are not considered to be AhR activators. We tested whether exposure to coffee would activate AhR in cultured cells. Methods HepG2 cells stably expressing an AhR-responsive reporter gene were treated with coffee samples. Also, expression of CYP1A1, an endogenous AhR-responsive gene, was quantitated by RT-PCR and Western blotting in HepG2, Caco-2, and MCF-7 cells, after treatment with coffee. In order to obtain sensitive and reproducible results, all the experiments were performed with the cells placed in either phosphate-buffered saline (PBS) or pure serum, instead of routinely-used culture medium, whose intrinsic AhR-stimulating activity turned out to be so strong as to interfere with the analyses. Results All the coffee samples tested robustly stimulated AhR-mediated transcription in the reporter gene assays. Of note, to what extent coffee and other AhR agonists activated AhR was different, depending on whether the experiments were done in PBS or serum. CYP1A1 mRNA was induced by coffee, in HepG2, Caco-2, and MCF-7 cells placed in either PBS or serum. CYP1A1 protein expression, which was not detected in these cells incubated in PBS, was also increased by coffee in cells placed in serum. Conclusions By using culture medium-free experimental settings, we have shown that coffee is a strong AhR activator. Our observation may help elucidate as-yet-unrecognized effects of coffee on human health. PMID:25007155

  5. A Robust Measurement of the Mass Outflow Rate of the Galactic Outflow from NGC 6090

    NASA Astrophysics Data System (ADS)

    Chisholm, John; Tremonti, Christy A.; Leitherer, Claus; Chen, Yanmei

    2016-08-01

    To evaluate the impact of stellar feedback, it is critical to estimate the mass outflow rates of galaxies. Past estimates have been plagued by uncertain assumptions about the outflow geometry, metallicity, and ionization fraction. Here we use Hubble Space Telescope ultraviolet spectroscopic observations of the nearby starburst NGC 6090 to demonstrate that many of these quantities can be constrained by the data. We use the Si IV absorption lines to calculate the scaling of velocity (v), covering fraction (Cf), and density with distance from the starburst (r), assuming the Sobolev optical depth and a velocity law of the form: v~∝(1 - Ri/r)β (where Ri is the inner outflow radius). We find that the velocity (β=0.43) is consistent with an outflow driven by an r-2 force with the outflow radially accelerated, while the scaling of the covering fraction (Cf∝r-0.82) suggests that cool clouds in the outflow are in pressure equilibrium with an adiabatically expanding medium. We use the column densities of four weak metal lines and CLOUDY photoionization models to determine the outflow metallicity, the ionization correction, and the initial density of the outflow. Combining these values with the profile fitting, we find Ri = 63 pc, with most of the mass within 300 pc of the starburst. Finally, we find that the maximum mass outflow rate is 2.3 M⊙ yr-1 and the mass loading factor (outflow divided by the star formation rate) is 0.09, a factor of 10 lower than the value calculated using common assumptions for the geometry, metallicity and ionization structure of the outflow.

  6. A robust measurement of the mass outflow rate of the galactic outflow from NGC 6090

    NASA Astrophysics Data System (ADS)

    Chisholm, John; Tremonti Christy, A.; Leitherer, Claus; Chen, Yanmei

    2016-11-01

    To evaluate the impact of stellar feedback, it is critical to estimate the mass outflow rates of galaxies. Past estimates have been plagued by uncertain assumptions about the outflow geometry, metallicity, and ionization fraction. Here we use Hubble Space Telescope ultraviolet spectroscopic observations of the nearby starburst NGC 6090 to demonstrate that many of these quantities can be constrained by the data. We use the Si IV absorption lines to calculate the scaling of velocity (v), covering fraction (Cf), and density with distance from the starburst (r), assuming the Sobolev optical depth and a velocity law of the form: v ∝ (1 - Ri/r)β (where Ri is the inner outflow radius). We find that the velocity (β = 0.43) is consistent with an outflow driven by an r-2 force with the outflow radially accelerated, while the scaling of the covering fraction (Cf ∝ r-0.82) suggests that cool clouds in the outflow are in pressure equilibrium with an adiabatically expanding medium. We use the column densities of four weak metal lines and CLOUDY photoionization models to determine the outflow metallicity, the ionization correction, and the initial density of the outflow. Combining these values with the profile fitting, we find Ri = 63 pc, with most of the mass within 300 pc of the starburst. Finally, we find that the maximum mass outflow rate is 2.3 M⊙ yr-1 and the mass-loading factor (outflow divided by the star formation rate) is 0.09, a factor of 10 lower than the value calculated using common assumptions for the geometry, metallicity, and ionization structure of the outflow.

  7. Bursty star formation feedback and cooling outflows

    NASA Astrophysics Data System (ADS)

    Suarez, Teresita; Pontzen, Andrew; Peiris, Hiranya V.; Slyz, Adrianne; Devriendt, Julien

    2016-10-01

    We study how outflows of gas launched from a central galaxy undergoing repeated starbursts propagate through the circum-galactic medium (CGM), using the simulation code RAMSES. We assume that the outflow from the disc can be modelled as a rapidly moving bubble of hot gas at ˜1 kpc above disc, then ask what happens as it moves out further into the halo around the galaxy on ˜100 kpc scales. To do this, we run 60 two-dimensional simulations scanning over parameters of the outflow. Each of these is repeated with and without radiative cooling, assuming a primordial gas composition to give a lower bound on the importance of cooling. In a large fraction of radiative-cooling cases we are able to form rapidly outflowing cool gas from in situ cooling of the flow. We show that the amount of cool gas formed depends strongly on the `burstiness' of energy injection; sharper, stronger bursts typically lead to a larger fraction of cool gas forming in the outflow. The abundance ratio of ions in the CGM may therefore change in response to the detailed historical pattern of star formation. For instance, outflows generated by star formation with short, intense bursts contain up to 60 per cent of their gas mass at temperatures <5 × 104 K; for near-continuous star formation, the figure is ≲5 per cent. Further study of cosmological simulations, and of idealized simulations with e.g. metal-cooling, magnetic fields and/or thermal conduction, will help to understand the precise signature of bursty outflows on observed ion abundances.

  8. Characterizing Quasar Outflows I: Sample, Spectral Measurements

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib; Christenson, D. H.; Richmond, J. M.; Derseweh, J. A.; Robbins, J. M.; Townsend, S. L.; Stark, M. A.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In this poster, we subjectively divide these quasars into four categories: broad absorption-line quasars (2700 objects), associated absorption-line quasars (1700 objects), reddened quasars (160 objects), and unabsorbed/unreddened quasars (6300 objects). We present measurements of the absorption (velocities, velocity widths, equivalent widths), composite spectral profiles of outflows as a function of velocity, as well as measurements of the continuum and CIV, MgII, and FeII emission-line properties. In accompanying posters, we add photometry from the rest-frame X-ray (ROSAT and Chandra), EUV (GALEX), optical (2MASS), and infrared (WISE) bands to complete the SED. The continuum and emission-line measurements from the SDSS spectra and accompanying photometry provides estimates on the black hole masses, bolometric luminsosities, and SED. We consider empirically how these affect the outflow properties. This material is based upon work supported by the National Aeronautics and Space Administration under

  9. Pressurized groundwater outflow experiments and numerical modeling for outflow channels on Mars

    NASA Astrophysics Data System (ADS)

    Marra, Wouter A.; Hauber, Ernst; McLelland, Stuart J.; Murphy, Brendan J.; Parsons, Daniel R.; Conway, Susan J.; Roda, Manuel; Govers, Rob; Kleinhans, Maarten G.

    2014-12-01

    The landscape of Mars shows incised channels that often appear abruptly in the landscape, suggesting a groundwater source. However, groundwater outflow processes are unable to explain the reconstructed peak discharges of the largest outflow channels based on their morphology. Therefore, there is a disconnect between groundwater outflow processes and the resulting morphology. Using a combined approach with experiments and numerical modeling, we examine outflow processes that result from pressurized groundwater. We use a large sandbox flume, where we apply a range of groundwater pressures at the base of a layer of sediment. Our experiments show that different pressures result in distinct outflow processes and resulting morphologies. Low groundwater pressure results in seepage, forming a shallow surface lake and a channel when the lake overflows. At intermediate groundwater pressures, fissures form and groundwater flows out more rapidly. At even higher pressures, the groundwater initially collects in a subsurface reservoir that grows due to flexural deformation of the surface. When this reservoir collapses, a large volume of water is released to the surface. We numerically model the ability of these processes to produce floods on Mars and compare the results to discharge estimates based on previous morphological studies. We show that groundwater seepage and fissure outflow are insufficient to explain the formation of large outflow channels from a single event. Instead, formation of a flexure-induced subsurface reservoir and subsequent collapse generates large floods that can explain the observed morphologies of the largest outflow channels on Mars and their source areas.

  10. Evolutionary and Developmental Origins of the Cardiac Neural Crest: Building a Divided Outflow Tract

    PubMed Central

    Keyte, Anna L.; Alonzo-Johnsen, Martha; Hutson, Mary R.

    2015-01-01

    The cardiac neural crest cells (CNCCs) have played an important role in the evolution and development of the vertebrate cardiovascular system: from reinforcement of the developing aortic arch arteries early in vertebrate evolution, to later orchestration of aortic arch artery remodeling into the great arteries of the heart, and finally outflow tract septation in amniotes. A critical element necessary for the evolutionary advent of outflow tract septation was the co-evolution of the cardiac neural crest cells with the second heart field. This review highlights the major transitions in vertebrate circulatory evolution, explores the evolutionary developmental origins of the CNCCs from the third stream cranial neural crest, and explores candidate signaling pathways in CNCC and outflow tract evolution drawn from our knowledge of DiGeorge Syndrome. PMID:25227322

  11. Evolutionary and developmental origins of the cardiac neural crest: building a divided outflow tract.

    PubMed

    Keyte, Anna L; Alonzo-Johnsen, Martha; Hutson, Mary R

    2014-09-01

    The cardiac neural crest cells (CNCCs) have played an important role in the evolution and development of the vertebrate cardiovascular system: from reinforcement of the developing aortic arch arteries early in vertebrate evolution, to later orchestration of aortic arch artery remodeling into the great arteries of the heart, and finally outflow tract septation in amniotes. A critical element necessary for the evolutionary advent of outflow tract septation was the co-evolution of the cardiac neural crest cells with the second heart field. This review highlights the major transitions in vertebrate circulatory evolution, explores the evolutionary developmental origins of the CNCCs from the third stream cranial neural crest, and explores candidate signaling pathways in CNCC and outflow tract evolution drawn from our knowledge of DiGeorge Syndrome.

  12. Northwestern Tharsis Latent Outflow Activity Mars

    NASA Technical Reports Server (NTRS)

    Dohm, J. M.; Anderson, R. C.; Baker, V. R.; Ferris, J. C.; Hare, T. M.; Strom, R. G.; Rudd, L.; Rice, J. W., Jr.; Scott, D. H.

    2000-01-01

    Previously defined outflow channels, which are indicated by relict landforms similar to those observed on Earth, signify ancient catastrophic flood events on Mars. These conspicuous geomorphic features are some of the most remarkable yet profound discoveries made by geologists to date. These outflow channels, which debouched tremendous volumes of water into topographic lows such as Chryse, Utopia, Elysium, and Hellas Planitiae, may represent the beginning of warmer and wetter climatic periods unlike the present-day cold and dry Mars. In addition to the previously identified outflow channels, observations permitted by the newly acquired Mars Orbiter Laser Altimeter (MOLA) data have revealed a system of gigantic valleys, referred to as the northwestern slope valleys (NSV), that are located to the northwest of a huge shield volcano, Arsia Mons, western hemisphere of Mars. These features generally correspond spatially to gravity lows similar to the easternmost, circum-Chryse outflow channel systems. Geologic investigations of the Tharsis region suggest that the large valley system pre-dates the construction of Arsia Mons and its extensive associated lava flows of mainly Late Hesperian and Amazonian age and coincides stratigraphically with the early development of the circum-Chryse outflow channel systems that debouch into Chryse Planitia. This newly identified system, the NSV, potentially signifies the largest flood event(s) ever recorded for the solar system. Additional information is contained in original extended abstract.

  13. Imaging and Simulations of CO Molecular Outflows

    NASA Astrophysics Data System (ADS)

    Lee, Chin-Fei; Mundy, Lee; Stone, James; Ostriker, Eve

    1999-10-01

    We have mapped the CO J=1-0 emission from molecular outflows associated with 10 young stellar systems of class 0 to class II with BIMA interferometry array and FCRAO single dish. Many of our outflows are closely related to jet like and bow shock structures detected in H2 or Halpha emission. The CO emission generally forms a hollowed structure around the jet and bow shock structures. Most of the CO outflows show a nested shell structure with velocity increasing with the distance from the star, but the detailed behavior can vary widely. Here, we presents five outflows to illustrate the different kinematics. Two of them are well described by a single parabolic shell with a Hubble law velocity, consistent with a wide-angle wind driven model. Two of them seem better explained with a jet-driven bow shock model, with a broad range of velocity near the bow shock. The last one appears to have elements of both models. To better understand the observations and test specific outflow models, we are performing a number of numerical simulations. This poster presents simulations of a jet propagating into a stratified ambient material. In these simulations, the jet-driven bow shock forms a thin cylindrical shell of swept-up gas around the jet, with the velocity vector of the material perpendicular to the shell surface. The simulations produce a wide range of velocity observed near the bow shock, but fail to produce the other CO kinematics in our observations.

  14. Galaxy ecosystems: gas contents, inflows and outflows

    NASA Astrophysics Data System (ADS)

    Lu, Zhankui; Mo, H. J.; Lu, Yu

    2015-06-01

    We use a set of observational data for galaxy cold gas mass fraction and gas phase metallicity to constrain the content, inflow and outflow of gas in central galaxies hosted by haloes with masses between 1011 and 1012 M⊙. The gas contents in high-redshift galaxies are obtained by combining the empirical star formation histories and star formation models that relate star formation rate with the cold gas mass in galaxies. We find that the total baryon mass in low-mass galaxies is always much less than the universal baryon mass fraction since z = 2, regardless of star formation model adopted. The data for the evolution of the gas phase metallicity require net metal outflow at z ≲ 2, and the metal loading factor is constrained to be about 0.01, or about 60 per cent of the metal yield. Based on the assumption that galactic outflow is more enriched in metal than both the interstellar medium and the material ejected at earlier epochs, we are able to put stringent constraints on the upper limits for both the net accretion rate and the net mass outflow rate. The upper limits strongly suggest that the evolution of the gas phase metallicity and gas mass fraction for low-mass galaxies at z < 2 is not compatible with strong outflow. We speculate that the low star formation efficiency of low-mass galaxies is owing to some preventative processes that prevent gas from accreting into galaxies in the first place.

  15. Cellular Basis for Bimatoprost Effects on Human Conventional Outflow

    PubMed Central

    Piwnica, David; Jolas, Thierry; Carling, Robert W.; Cornell, Clive L.; Fliri, Hans; Martos, Jose; Pettit, Simon N.; Wang, Jenny W.; Woodward, David F.

    2010-01-01

    Purpose. Bimatoprost is a widely used ocular hypotensive agent to treat glaucoma. It lowers intraocular pressure in humans by increasing both pressure-independent (uveoscleral) and pressure-dependent (conventional) aqueous humor outflow. The present study specifically examines bimatoprost effects on the cells that populate human outflow tissues. Methods. The authors tested for prostamide receptor activation in primary cultures of human trabecular meshwork (TM), Schlemm's canal (SC), and ciliary smooth muscle (CSM) cells using cellular dielectric spectroscopy (CDS). Results. The authors observed that bimatoprost produced an immediate and concentration-dependent increase in cell monolayer impedance for TM, SC, and CSM cells with EC50 values of 4.3, 1.2, and 1.7 nM, respectively; corresponding to decreased cell contractility. Notably, in TM, SC, and CSM cells, bimatoprost was approximately equipotent to the selective FP receptor agonists fluprostenol and 17-phenyl PGF2α. Bimatoprost effects were insensitive to cholera toxin and pertussis toxin but were abolished by phorbol 12-myristate 13-acetate pretreatment, suggesting Gq-involvement in cell signaling. The effects of bimatoprost on TM and SC cells were inhibited by the prostamide receptor antagonist AGN211334, with IC50 values of 1.2 and 3.3 μM, respectively. Interestingly, AGN211334 behaved as an apparent inverse agonist in CDS assays involving TM cells but as a neutral prostamide antagonist with SC cells. Conclusions. Taken together, results suggest that bimatoprost specifically activates receptors in both cell types of the human conventional outflow pathway to modify intraocular pressure. However, only TM cell monolayers appear to have autocrine, or agonist-independent, receptor signaling that is sensitive to a prostamide receptor antagonist. PMID:20435598

  16. Zooplankton in the Arctic outflow

    NASA Astrophysics Data System (ADS)

    Soloviev, K. A.; Dritz, A. V.; Nikishina, A. B.

    2009-04-01

    Climate changes in the Arctic cause the changes in the current system that may have cascading effect on the structure of plankton community and consequently on the interlinked and delicately balanced food web. Zooplankton species are by definition incapable to perform horizontal moving. Their transport is connected with flowing water. There are zooplankton species specific for the definite water masses and they can be used as markers for the different currents. That allows us to consider zooplankton community composition as a result of water mixing in the studied area. Little is known however about the mechanisms by which spatial and temporal variability in advection affect dynamics of local populations. Ice conditions are also very important in the function of pelagic communities. Melting time is the trigger to all "plankton blooming" processes, and the duration of ice-free conditions determines the food web development in the future. Fram Strait is one of the key regions for the Arctic: the cold water outflow comes through it with the East Greenland Current and meets warm Atlantic water, the West Spitsbergen Current, producing complicated hydrological situation. During 2007 and 2008 we investigated the structure functional characteristics of zooplankton community in the Fram Strait region onboard KV "Svalbard" (April 2007, April and May 2008) and RV "Jan Mayen" (May 2007, August 2008). This study was conducted in frame of iAOOS Norway project "Closing the loop", which, in turn, was a part of IPY. During this cruises multidisciplinary investigations were performed, including sea-ice observations, CTD and ADCP profiling, carbon flux, nutrients and primary production measurements, phytoplankton sampling. Zooplankton was collected with the Hydro-Bios WP2 net and MultiNet Zooplankton Sampler, (mouth area 0.25 m2, mesh size 180 um).Samples were taken from the depth strata of 2000-1500, 1500-1000, 1000-500,500-200, 200-100, 100-60, 60-30, 30-0 m. Gut fluorescence

  17. Observations of Protostellar Outflow Feedback in Clustered Star Formation

    NASA Astrophysics Data System (ADS)

    Nakamura, F.

    2016-05-01

    We discuss the role of protostellar outflow feedback in clustered star formation using the observational data of recent molecular outflow surveys toward nearby cluster-forming clumps. We found that for almost all clumps, the outflow momentum injection rate is significantly larger than the turbulence dissipation rate. Therefore, the outflow feedback is likely to maintain supersonic turbulence in the clumps. For less massive clumps such as B59, L1551, and L1641N, the outflow kinetic energy is comparable to the clump gravitational energy. In such clumps, the outflow feedback probably affects significantly the clump dynamics. On the other hand, for clumps with masses larger than about 200 M⊙, the outflow kinetic energy is significantly smaller than the clump gravitational energy. Since the majority of stars form in such clumps, we conclude that outflow feedback cannot destroy the whole parent clump. These characteristics of the outflow feedback support the scenario of slow star formation.

  18. Fibroblast growth factor (Fgf) 21 is a novel target gene of the aryl hydrocarbon receptor (AhR)

    SciTech Connect

    Cheng, Xingguo; Vispute, Saurabh G.; Liu, Jie; Cheng, Christine; Kharitonenkov, Alexei; Klaassen, Curtis D.

    2014-07-01

    The toxic effects of dioxins, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), mainly through activation of the aryl hydrocarbon receptor (AhR) are well documented. Fibroblast growth factor (Fgf) 21 plays critical roles in metabolic adaptation to fasting by increasing lipid oxidation and ketogenesis in the liver. The present study was performed to determine whether activation of the AhR induces Fgf21 expression. In mouse liver, TCDD increased Fgf21 mRNA in both dose- and time-dependent manners. In addition, TCDD markedly increased Fgf21 mRNA expression in cultured mouse and human hepatocytes. Moreover, TCDD increased mRNA (in liver) and protein levels (in both liver and serum) of Fgf21 in wild-type mice, but not in AhR-null mice. Chromatin immunoprecipitation assays showed that TCDD increased AhR protein binding to the Fgf21 promoter (− 105/+ 1 base pair). Fgf21-null mice administered 200 μg/kg of TCDD died within 20 days, whereas wild-type mice receiving the same treatment were still alive at one month after administration. This indicates that TCDD-induced Fgf21 expression protects against TCDD toxicity. Diethylhexylphthalate (DEHP) pretreatment attenuated TCDD-induced Fgf21 expression in mouse liver and white adipose tissue, which may explain a previous report that DEHP pretreatment decreases TCDD-induced wasting. In conclusion, Fgf21 appears to be a target gene of AhR-signaling pathway in mouse and human liver. - Highlights: • TCDD induced Fgf21 expression at both mRNA and protein levels. • Fgf21 induction by TCDD is AhR-dependent. • DEHP attenuated TCDD-induced Fgf21 expression.

  19. Outflows from Accretion Disks around Compact Objects

    NASA Astrophysics Data System (ADS)

    Jiao, Cheng-Liang; Wu, Xue-Bing

    2013-02-01

    We solve the set of hydrodynamic equations for accretion disks in the spherical coordinates (rθφ) to obtain the explicit structure along the θ direction. The results display thinner, quasi-Keplerian disks for Shakura-Sunyaev Disks (SSDs) and thicker, sub-Keplerian disks for Advection Dominated Accretion Flows (ADAFs) and slim disks, which are consistent with previous popular analytical models, while an inflow region and an outflow region always exist, which supports the results of some recent numerical simulation works. Our results indicate that the outflows should be common in various accretion disks and stronger in slim disks and ADAFs.

  20. Episodic High-velocity Outflows from V899 Mon: A Constraint On The Outflow Mechanisms

    NASA Astrophysics Data System (ADS)

    Ninan, J. P.; Ojha, D. K.; Philip, N. S.

    2016-07-01

    We report the detection of large variations in the outflow wind velocity from a young eruptive star, V899 Mon, during its ongoing high accretion outburst phase. Such large variations in the outflow velocity (from -722 to -425 km s-1) have never been reported previously in this family of objects. Our continuous monitoring of this source shows that the multi-component, clumpy, and episodic high velocity outflows are stable in the timescale of a few days, and vary over the timescale of a few weeks to months. We detect significant decoupling in the instantaneous outflow strength to accretion rate. From the comparison of various possible outflow mechanisms in magnetospheric accretion of young stellar objects, we conclude magnetically driven polar winds to be the most consistent mechanism for the outflows seen in V899 Mon. The large scale fluctuations in outflow over the short period makes V899 Mon the most ideal source to constrain various magnetohydrodynamics simulations of magnetospheric accretion. Based on observations made with the Southern African Large Telescope (SALT).

  1. TRPV4 regulates calcium homeostasis, cytoskeletal remodeling, conventional outflow and intraocular pressure in the mammalian eye

    PubMed Central

    Ryskamp, Daniel A.; Frye, Amber M.; Phuong, Tam T. T.; Yarishkin, Oleg; Jo, Andrew O.; Xu, Yong; Lakk, Monika; Iuso, Anthony; Redmon, Sarah N.; Ambati, Balamurali; Hageman, Gregory; Prestwich, Glenn D.; Torrejon, Karen Y.; Križaj, David

    2016-01-01

    An intractable challenge in glaucoma treatment has been to identify druggable targets within the conventional aqueous humor outflow pathway, which is thought to be regulated/dysregulated by elusive mechanosensitive protein(s). Here, biochemical and functional analyses localized the putative mechanosensitive cation channel TRPV4 to the plasma membrane of primary and immortalized human TM (hTM) cells, and to human and mouse TM tissue. Selective TRPV4 agonists and substrate stretch evoked TRPV4-dependent cation/Ca2+ influx, thickening of F-actin stress fibers and reinforcement of focal adhesion contacts. TRPV4 inhibition enhanced the outflow facility and lowered perfusate pressure in biomimetic TM scaffolds populated with primary hTM cells. Systemic delivery, intraocular injection or topical application of putative TRPV4 antagonist prodrug analogs lowered IOP in glaucomatous mouse eyes and protected retinal neurons from IOP-induced death. Together, these findings indicate that TRPV4 channels function as a critical component of mechanosensitive, Ca2+-signaling machinery within the TM, and that TRPV4-dependent cytoskeletal remodeling regulates TM stiffness and outflow. Thus, TRPV4 is a potential IOP sensor within the conventional outflow pathway and a novel target for treating ocular hypertension. PMID:27510430

  2. AH-1S communication switch integration program

    NASA Technical Reports Server (NTRS)

    Haworth, Loran; Szoboszlay, Zoltan; Shively, Robert; Bick, Frank J.

    1989-01-01

    The C-6533/ARC communication system as installed on the test AH-1E Cobra helicopter was modified to allow discrete radio selection of all aircraft radios at the cyclic radio/intercommunication system switch. The current Cobra-fleet use of the C-6533 system is cumbersome, particularly during low-altitude operations. Operationally, the current system C-6533 configuration and design requires the pilot to estimate when he can safely remove his hand from an active flight control to select radios during low-altitude flight. The pilot must then physically remove his hand from the flight control, look inside the cockpit to select and verify the radio selection and then effect the selected radio transmission by activating the radio/ICS switch on the cyclic. This condition is potentially hazardous, especially during low-level flight at night in degraded weather. To improve pilot performance, communications effectiveness, and safety, manprint principles were utilized in the selection of a design modification. The modified C-6533 design was kept as basic as possible for potential Cobra-fleet modification. The communications system was modified and the design was subsequently flight-tested by the U.S. Army Aeroflightdynamics Directorate and NASA at the NASA Ames Research Center, Mountain View, California. The design modification enables the Cobra pilot to maintain hands-on flight controls while selecting radios during nap-of-the-Earth (NOE) flight without looking inside the cockpit which resulted in reduced pilot workload ratings, better pilot handling quality ratings and increased flight safety for the NOE flight environment.

  3. Where is the oxygen in protostellar outflows?

    NASA Astrophysics Data System (ADS)

    Kristensen, Lars

    2014-10-01

    Oxygen (O) is the third-most abundant element in the Universe after hydrogen and helium. Despite its high elemental abundance, a good picture of where oxygen is located in low-mass protostellar outflows and jets is missing: we cannot account for > 60% of the oxygen budget in these objects. This hole in our picture means that we currently do not have a good understanding of the dominant cooling processes in outflows jets, despite the fact that [O I] emission at 63 micron is one of the dominant cooling lines, nor how cooling processes evolve with protostellar evolution. To shed light on these processes, we propose to observe the [O I] 63 micron line with SOFIA-GREAT toward five low-mass protostars. As a first step, the velocity-resolved line profile will be decomposed into its constituent components to isolate the relative contributions from the jet and the irradiated outflow. Second, the [O I] line profile will be compared to those of H2O, OH and CO to obtain the relative atomic O abundance with respect to CO, H2O, and OH. Third, the effects of evolution will be examined by observing protostars at different evolutionary stages. These three approaches will allow us to quantify: the oxygen chemistry in warm and hot gas, the relative amounts of material in the outflow and the jet, and finally to start tracing the evolutionary sequence of how feedback evolves with time.

  4. Did ice streams carve martian outflow channels?

    USGS Publications Warehouse

    Lucchitta, B.K.; Anderson, D.M.; Shoji, H.

    1981-01-01

    Outflow channels on Mars1 are long sinuous linear depressions that occur mostly in the equatorial area (??30?? lat.). They differ from small valley networks2 by being larger and arising full born from chaotic terrains. Outflow channels resemble terrestrial stream beds, and their origin has generally been attributed to water3-5 in catastrophic floods6,7 or mudflows8. The catastrophic-flood hypothesis is derived primarily from the morphological similarities of martian outflow channels and features created by the catastrophic Spokane flood that formed the Washington scablands. These similarities have been documented extensively3,6,7, but differences of scale remain a major problemmartian channel features are on the average much larger than their proposed terrestrial analogues. We examine here the problem of channel origin from the perspective of erosional characteristics and the resultant landf orms created by former and present-day ice streams and glaciers on Earth. From morphologic comparisons, an ice-stream origin seems equally well suited to explain the occurrences and form of the outflow channels on Mars, and in contrast with the hydraulic hypothesis, ice streams and ice sheets produce terrestrial features of the same scale as those observed on Mars. ?? 1981 Nature Publishing Group.

  5. A SPECTACULAR OUTFLOW IN AN OBSCURED QUASAR

    SciTech Connect

    Greene, Jenny E.; Zakamska, Nadia L.; Smith, Paul S.

    2012-02-10

    SDSS J1356+1026 is a pair of interacting galaxies at redshift z = 0.123 that hosts a luminous obscured quasar in its northern nucleus. Here we present two long-slit Magellan LDSS-3 spectra that reveal a pair of symmetric {approx}10 kpc size outflows emerging from this nucleus, with observed expansion velocities of {approx}250 km s{sup -1} in projection. We present a kinematic model of these outflows and argue that the deprojected physical velocities of expansion are likely {approx}1000 km s{sup -1} and that the kinetic energy of the expanding shells is likely 10{sup 44-45} erg s{sup -1}, with an absolute minimum of >10{sup 42} erg s{sup -1}. Although a radio counterpart is detected at 1.4 GHz, it is faint enough that the quasar is considered to be radio quiet by all standard criteria, and there is no evidence of extended emission due to radio lobes, whether aged or continuously powered by an ongoing jet. We argue that the likely level of star formation is insufficient to power the observed energetic outflow and that SDSS J1356+1026 is a good case for radio-quiet quasar feedback. In further support of this hypothesis, polarimetric observations show that the direction of quasar illumination is coincident with the direction of the outflow.

  6. A Well-Defined Bipolar Outflow Shell

    NASA Astrophysics Data System (ADS)

    Xie, Taoling; Goldsmith, Paul F.; Patel, Nimesh

    1992-12-01

    A well-defined "eggplant-shaped" thin shell is revealed in the Mon R2 central core region by CO and (13) CO J=1-0 maps obtained with QUARRY. This thin shell outlines the extended blue lobe of the massive bipolar outflow. The projected length and width of the shell are about 5.7 pc and 2.5 pc respectively, and the averaged projected thickness of the shell is ~ 0.3 pc. The shape of this shell can be satisfactorily accounted for quantitatively in terms of limb-brightening within the framework of the Shu et al shell model with radially directed wind, although the model seems to be oversimplified with respect to the complexity that our data reveal. The outflow shell's symmetry axis is estimated to be inclined by ~ 70(deg) with respect to the line of sight. We suggest that the coincident blue- and red-shifted emission and the bending of the red-shifted lobe are the result of the red-shifted shell being compressed, rather than having a second bipolar outflow aligned roughly perpendicular to the axis of the first bipolar outflow.

  7. Protostellar Outflow Evolution in Turbulent Environments

    SciTech Connect

    Cunningham, A; Frank, A; Carroll, J; Blackman, E; Quillen, A

    2008-04-11

    The link between turbulence in star formatting environments and protostellar jets remains controversial. To explore issues of turbulence and fossil cavities driven by young stellar outflows we present a series of numerical simulations tracking the evolution of transient protostellar jets driven into a turbulent medium. Our simulations show both the effect of turbulence on outflow structures and, conversely, the effect of outflows on the ambient turbulence. We demonstrate how turbulence will lead to strong modifications in jet morphology. More importantly, we demonstrate that individual transient outflows have the capacity to re-energize decaying turbulence. Our simulations support a scenario in which the directed energy/momentum associated with cavities is randomized as the cavities are disrupted by dynamical instabilities seeded by the ambient turbulence. Consideration of the energy power spectra of the simulations reveals that the disruption of the cavities powers an energy cascade consistent with Burgers-type turbulence and produces a driving scale-length associated with the cavity propagation length. We conclude that fossil cavities interacting either with a turbulent medium or with other cavities have the capacity to sustain or create turbulent flows in star forming environments. In the last section we contrast our work and its conclusions with previous studies which claim that jets can not be the source of turbulence.

  8. Enhancing trabecular outflow by disrupting the actin cytoskeleton, increasing uveoscleral outflow with prostaglandins, and understanding the pathophysiology of presbyopia

    PubMed Central

    Kaufman, Paul L.

    2008-01-01

    Several major areas of work by the author and his international collaborators are reviewed. 1) The ciliary muscle in the nonhuman primate eye was disinserted at the scleral spur. Pilocarpine was then ineffective in increasing outflow facility, indicating that ciliary muscle contraction mediated the IOP-lowering effect of muscarinic cholinergics. 2) Compounds such as cytochalasins, H-7 and latrunculin A/B, which alter the actin cytoskeleton, cellular contractility and cellular adhesions in cultured trabecular meshwork cells, relaxed trabecular pathway cells and consequently the meshwork itself so as to decrease IOP and enhance trabecular outflow facility in nonhuman primates. Gene transfer approaches utilizing C3 and caldesmon over-expression by viral vectors to target specific steps in the cellular contractility/cytoskeleton/cell adhesion cascades characteristically altered trabecular meshwork cell morphology and increased outflow facility in organ-cultured anterior segments. 3) Prostaglandin F2α analogues enhanced matrix metalloproteinase production by ciliary muscle cells and scleral fibroblasts, leading to remodeling of the extracellular matrix of the ciliary muscle and sclera and consequently to increased uveoslceral outflow and decreased IOP in primates. 4) The rhesus monkey was an excellent model for human presbyopia, losing the accommodative response to cholinergic stimulation in the same timeframe relative to lifespan. No changes were found in ciliary muscle enzymes involved in acetylcholine biosynthesis or degradation or in muscarinic receptor numbers or affinity. Contractility of isolated ciliary muscle did not diminish with age, but posterior ciliary muscle attachments stiffened, suggesting a possible role in restricting muscle and consequently lens movement during accommodation. A model to reproducibly stimulate accommodation through central stimulation of the Edinger-Westphal nucleus was developed. Goniovideography and ultrasound biomicroscopic

  9. The Resolved Outflow from 3C 48

    NASA Astrophysics Data System (ADS)

    Shih, Hsin-Yi; Stockton, Alan

    2014-10-01

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 103-104 cm-3, the mass is ~6 × 106 M ⊙, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-11574. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Some of the

  10. Evolution of Mass Outflow in Protostars

    NASA Astrophysics Data System (ADS)

    Watson, Dan M.; Calvet, Nuria P.; Fischer, William J.; Forrest, W. J.; Manoj, P.; Megeath, S. Thomas; Melnick, Gary J.; Najita, Joan; Neufeld, David A.; Sheehan, Patrick D.; Stutz, Amelia M.; Tobin, John J.

    2016-09-01

    We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in mid-infrared [Si ii], [Fe ii], and [S i] line emission, and 11 of these in far-infrared [O i] emission. We use the results to derive their mass outflow rates, {\\dot{M}}w. Thereby we observe a strong correlation of {\\dot{M}}w with bolometric luminosity, and with the inferred mass accretion rates of the central objects, {\\dot{M}}a, which continues through the Class 0 range the trend observed in Class II young stellar objects. Along this trend from large to small mass flow rates, the different classes of young stellar objects lie in the sequence Class 0-Class I/flat-spectrum-Class II, indicating that the trend is an evolutionary sequence in which {\\dot{M}}a and {\\dot{M}}w decrease together with increasing age, while maintaining rough proportionality. The survey results include two that are key tests of magnetocentrifugal outflow-acceleration mechanisms: the distribution of the outflow/accretion branching ratio b={\\dot{M}}w/{\\dot{M}}a, and limits on the distribution of outflow speeds. Neither rules out any of the three leading outflow-acceleration, angular-momentum-ejection mechanisms, but they provide some evidence that disk winds and accretion-powered stellar winds (APSWs) operate in many protostars. An upper edge observed in the branching-ratio distribution is consistent with the upper bound of b = 0.6 found in models of APSWs, and a large fraction (31%) of the sample have a branching ratio sufficiently small that only disk winds, launched on scales as large as several au, have been demonstrated to account for them.

  11. HOT ELECTROMAGNETIC OUTFLOWS. I. ACCELERATION AND SPECTRA

    SciTech Connect

    Russo, Matthew; Thompson, Christopher

    2013-04-20

    The theory of cold, relativistic, magnetohydrodynamic outflows is generalized by the inclusion of an intense radiation source. In some contexts, such as the breakout of a gamma-ray burst (GRB) jet from a star, the outflow is heated to a high temperature at a large optical depth. Eventually it becomes transparent and is pushed to a higher Lorentz factor by a combination of the Lorentz force and radiation pressure. We obtain its profile, both inside and outside the fast magnetosonic critical point, when the poloidal magnetic field is radial and monopolar. Most of the energy flux is carried by the radiation field and the toroidal magnetic field that is wound up close to the rapidly rotating engine. Although the entrained matter carries little energy, it couples the radiation field to the magnetic field. Then the fast critical point is pulled inward from infinity and, above a critical radiation intensity, the outflow is accelerated mainly by radiation pressure. We identify a distinct observational signature of this hybrid outflow: a hardening of the radiation spectrum above the peak of the seed photon distribution, driven by bulk Compton scattering. The non-thermal spectrum-obtained by a Monte Carlo method-is most extended when the Lorentz force dominates the acceleration, and the seed photon beam is wider than the Lorentz cone of the MHD fluid. This effect is a generic feature of hot, magnetized outflows interacting with slower relativistic material. It may explain why some GRB spectra appear to peak at photon energies above the original Amati et al. scaling. A companion paper addresses the case of jet breakout, where diverging magnetic flux surfaces yield strong MHD acceleration over a wider range of Lorentz factor.

  12. Evolution of Mass Outflow in Protostars

    NASA Astrophysics Data System (ADS)

    Watson, Dan M.; Calvet, Nuria P.; Fischer, William J.; Forrest, W. J.; Manoj, P.; Megeath, S. Thomas; Melnick, Gary J.; Najita, Joan; Neufeld, David A.; Sheehan, Patrick D.; Stutz, Amelia M.; Tobin, John J.

    2016-09-01

    We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in mid-infrared [Si ii], [Fe ii], and [S i] line emission, and 11 of these in far-infrared [O i] emission. We use the results to derive their mass outflow rates, {\\dot{M}}w. Thereby we observe a strong correlation of {\\dot{M}}w with bolometric luminosity, and with the inferred mass accretion rates of the central objects, {\\dot{M}}a, which continues through the Class 0 range the trend observed in Class II young stellar objects. Along this trend from large to small mass flow rates, the different classes of young stellar objects lie in the sequence Class 0–Class I/flat-spectrum–Class II, indicating that the trend is an evolutionary sequence in which {\\dot{M}}a and {\\dot{M}}w decrease together with increasing age, while maintaining rough proportionality. The survey results include two that are key tests of magnetocentrifugal outflow-acceleration mechanisms: the distribution of the outflow/accretion branching ratio b={\\dot{M}}w/{\\dot{M}}a, and limits on the distribution of outflow speeds. Neither rules out any of the three leading outflow-acceleration, angular-momentum-ejection mechanisms, but they provide some evidence that disk winds and accretion-powered stellar winds (APSWs) operate in many protostars. An upper edge observed in the branching-ratio distribution is consistent with the upper bound of b = 0.6 found in models of APSWs, and a large fraction (31%) of the sample have a branching ratio sufficiently small that only disk winds, launched on scales as large as several au, have been demonstrated to account for them.

  13. Baicalein induces G1 arrest in oral cancer cells by enhancing the degradation of cyclin D1 and activating AhR to decrease Rb phosphorylation

    SciTech Connect

    Cheng, Ya-Hsin; Li, Lih-Ann; Lin, Pinpin; Cheng, Li-Chuan; Hung, Chein-Hui; Chang, Nai Wen; Lin, Chingju

    2012-09-15

    Baicalein is a flavonoid, known to have anti-inflammatory and anti-cancer effects. As an aryl hydrocarbon receptor (AhR) ligand, baicalein at high concentrations blocks AhR-mediated dioxin toxicity. Because AhR had been reported to play a role in regulating the cell cycle, we suspected that the anti-cancer effect of baicalein is associated with AhR. This study investigated the molecular mechanism involved in the anti-cancer effect of baicalein in oral cancer cells HSC-3, including whether such effect would be AhR-mediated. Results revealed that baicalein inhibited cell proliferation and increased AhR activity in a dose-dependent manner. Cell cycle was arrested at the G1 phase and the expression of CDK4, cyclin D1, and phosphorylated retinoblastoma (pRb) was decreased. When the AhR was suppressed by siRNA, the reduction of pRb was partially reversed, accompanied by a decrease of cell population at G1 phase and an increase at S phase, while the reduction of cyclin D1 and CDK4 did not change. This finding suggests that the baicalein activation of AhR is indeed associated with the reduction of pRb, but is independent of the reduction of cyclin D1 and CDK4. When cells were pre-treated with LiCl, the inhibitor of GSK-3β, the decrease of cyclin D1 was blocked and the reduction of pRb was recovered. The data indicates that in HSC-3 the reduction of pRb is both mediated by baicalein through activation of AhR and facilitation of cyclin D1 degradation, which causes cell cycle arrest at the G1 phase, and results in the inhibition of cell proliferation. -- Highlights: ► Baicalein causes the G1 phase arrest by decreasing Rb phosphorylation. ► Baicalein modulates AhR-mediated cell proliferation. ► Both AhR activation and cyclin D1 degradation results in hypophosphorylation of Rb. ► Baicalein facilitates cyclin D1 degradation by signalling the GSK-3β pathway.

  14. Tracing outflows in the AGN forbidden region with SINFONI

    NASA Astrophysics Data System (ADS)

    Kakkad, D.; Mainieri, V.; Padovani, P.; Cresci, G.; Husemann, B.; Carniani, S.; Brusa, M.; Lamastra, A.; Lanzuisi, G.; Piconcelli, E.; Schramm, M.

    2016-08-01

    Context. Active galactic nucleus (AGN) driven outflows are invoked in numerical simulations to reproduce several observed properties of local galaxies. The z > 1 epoch is of particular interest as it was during this time that the volume averaged star formation and the accretion rate of black holes were at their maximum. Radiatively driven outflows are therefore believed to be common during this epoch. Aims: We aim to trace and characterize outflows in AGN hosts with high mass accretion rates at z > 1 using integral field spectroscopy. We obtain spatially resolved kinematics of the [O iii] λ5007 line in two targets which reveal the morphology and spatial extension of the outflows. Methods: We present SINFONI observations in the J band and the H + K band of five AGNs at 1.2 < z < 2.2. To maximize the chance of observing radiatively driven outflows, our sample was pre-selected based on peculiar values of the Eddington ratio and the hydrogen column density of the surrounding interstellar medium. We observe high velocity (~600-1900 km s-1) and kiloparsec scale extended ionized outflows in at least three of our targets, using [O iii] λ5007 line kinematics tracing the AGN narrow line region. We estimate the total mass of the outflow, the mass outflow rate, and the kinetic power of the outflows based on theoretical models and report on the uncertainties associated with them. Results: We find mass outflow rates of ~1-10 M⊙/yr for the sample presented in this paper. Based on the high star formation rates of the host galaxies, the observed outflow kinetic power, and the expected power due to the AGN, we infer that both star formation and AGN radiation could be the dominant source for the outflows. The outflow models suffer from large uncertainties, hence we call for further detailed observations for an accurate determination of the outflow properties to confirm the exact source of these outflows.

  15. Properties of quasar broad absorption line outflows

    NASA Astrophysics Data System (ADS)

    Capellupo, Daniel Moshin

    2012-06-01

    Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. In this dissertation, I use two methods to illuminate important properties of these outflows with the goal of a better understanding of these outflow systems and ultimately of the connection between quasars and their host galaxies. The variability of BALs can help us understand the structure, evolution, and basic physical properties of the outflows. I report here on a BAL monitoring programme of a sample of 24 luminous quasars at redshifts 1.2outflow velocities are more likely to vary than those at lower velocities, and weaker BALs are more likely to vary than stronger BALs. I then directly compare the variabilities in the C IV and Si IV lambda1400 absorption to try to ascertain the cause(s) of the variability. I find that Si IV BALs are more likely to vary than C IV BALs. When both C IV and Si IV varied, those changes always occurred in the same sense (either getting weaker or stronger). The multi-epoch data, including up to 10 epochs of data per quasar, show that the BAL changes were not generally monotonic across the full ˜5 to ˜8 yr time span of our observations, suggesting that the characteristic time-scale for significant line variations, and (perhaps) for structural changes in the outflows, is less than a few years. The evidence presented here indicates that the cause of variability is likely a complex mixture of changing ionization in the outflowing

  16. Ah receptor mediated suppression of the antibody response in mice is primarily dependent on the Ah phenotype of lymphoid tissue.

    PubMed

    Silkworth, J B; Antrim, L A; Sack, G

    1986-12-01

    Halogenated aromatic hydrocarbons act through the aromatic hydrocarbon (Ah) receptor in mice to produce a series of toxic effects of the immune system. The receptor protein is a product of the Ah gene locus. Ah responsive (Ahb/Ahb) mice express a high affinity receptor in both lymphoid and nonlymphoid tissues whereas nonresponsive Ahd/Ahd mice express a poor affinity receptor. To determine the role of the Ah receptor of lymphoid tissue relative to that of nonlymphoid tissue in the induction of immune impairment, bone marrow was used to reconstitute lethally irradiated mice of the same or opposite Ah phenotype. All mice were given 3,3',4,4'-tetrachlorobiphenyl (35 and 350 mumol/kg) ip 2 days before immunization with sheep erythrocytes (SRBC). The immune response to this T dependent antigen and organ weights were determined 5 or 7 days later in normal or chimeric mice, respectively. Monoclonal Lyt 1.1 and Lyt 1.2 antibodies were used to establish the origin of the cells which repopulated the chimeric thymuses. The immune responses of both BALB/cBy (Ahb/Ahb) and the BALB/cBy X DBA/2 hybrid, CByD2F1 (Ahb/Ahd), were significantly suppressed but DBA/2 mice were unaffected. The immune responses of chimeric BALB/cBy----BALB/cBy and BALB/cBy----DBA/2 (donor----recipient) mice were also significantly suppressed and thymic atrophy was observed in both cases. The serum anti-SRBC antibody titers of DBA/2----BALB/cBy chimeras were also significantly decreased although not to the same extent as in BALB/cBy----DBA/2 mice. Chimeric DBA/2----DBA/2 mice were not affected. These results indicate that the sensitivity to Ah receptor mediated suppression of the antibody response is primarily determined by the Ah phenotype of the lymphoid tissue.

  17. Molecular emission in chemically active protostellar outflows

    NASA Astrophysics Data System (ADS)

    Lefloch, B.

    2011-12-01

    Protostellar outflows play an important role in the dynamical and chemical evolution of cloud through shocks. The Herschel Space Observatory (HSO) brings new insight both on the molecular content and the physical conditions in protostellar shocks through high spectral and angular resolution studies of the emission of major gas cooling agents and hydrides. The Herschel/CHESS key-program is carrying out an in depth study of the prototypical shock region L1157-B1. Analysis of the line profiles detected allows to constrain the formation/destruction route of various molecular species, in relation with the predictions of MHD shock models. The Herschel/WISH key-program investigates the properties and origin of water emission in a broad sample of protostellar outflows and envelopes. Implications of the first results for future studies on mass-loss phenomena are discussed.

  18. Influence of Mediterranean Outflow on climate

    NASA Astrophysics Data System (ADS)

    Rahmstorf, Stefan

    A cover article in Eos last year [Johnson, 1997] called for a dam across the Strait of Gibraltar to prevent a new Ice Age. In this article, R. G. Johnson argued that reduced Nile River flow after building the Aswan Dam increases Mediterranean Sea salinity, leading to enhanced outflow of salty water into the Atlantic Ocean. This, in turn, would alter the thermohaline (that is, temperature and salinity driven) circulation of the Atlantic, heat up the Labrador Sea and enhance evaporation there, and increase snowfall in Canada until a new ice sheet builds up. Ocean circulation model experiments, however, suggest that this fear is unfounded. While Mediterranean saltwater outflow (Figure 1a) does appear to have some effect on North Atlantic circulation and surface climate, the change in Mediterranean salt budget resulting from the Aswan Dam is far too small to have any noticeable impact.

  19. Example of reduced turbulence during thunderstorm outflow

    SciTech Connect

    Bowen, B.M.

    1996-06-01

    This research note describes the effects of a gust front passage resulting from a thunderstorm outflow on wind, turbulence, and other basic meteorological variables in northern Mew Mexico. The purpose of this note is to explain how a thunderstorm outflow can greatly reduce horizontal and vertical turbulence and produce strong winds, thereby promoting the rapid transport of elevated pollutant concentrations. Another goal is to demonstrate the usefulness of a sodar in combination with a tower to provide data for dispersion and transport calculations during an emergency response. Hopefully, this note will motivate other researchers to analyze and document the effects of thunderstorms on turbulence and dispersion by routine monitoring or by experimentation. 12 refs., 3 figs., 1 tab.

  20. Local outflows from turbulent accretion disks

    NASA Astrophysics Data System (ADS)

    Fromang, S.; Latter, H.; Lesur, G.; Ogilvie, G. I.

    2013-04-01

    Aims: The aim of this paper is to investigate the properties of accretion disks threaded by a weak vertical magnetic field, with a particular focus on the interplay between magnetohydrodynamic (MHD) turbulence driven by the magnetorotational instability (MRI) and outflows that might be launched from the disk. Methods: For that purpose, we use a set of numerical simulations performed with the MHD code RAMSES in the framework of the shearing box model. We concentrate on the case of a rather weak vertical magnetic field such that the initial ratio β0 of the thermal and magnetic pressures in the disk midplane equals 104. Results: As reported recently, we find that MHD turbulence drives an efficient outflow out of the computational box. We demonstrate a strong sensitivity of that result to the box size: enlargements in the radial and vertical directions lead to a reduction of up to an order of magnitude in the mass-loss rate. Such a dependence prevents any realistic estimates of disk mass-loss rates being derived using shearing-box simulations. We find however that the flow morphology is robust and independent of the numerical details of the simulations. Its properties display some features and approximate invariants that are reminiscent of the Blandford & Payne launching mechanism, but differences exist. For the magnetic field strength considered in this paper, we also find that angular momentum transport is most likely dominated by MHD turbulence, the saturation of which scales with the magnetic Prandtl number, the ratio of viscosity and resistivity, in a way that is in good agreement with expectations based on unstratified simulations. Conclusions: This paper thus demonstrates for the first time that accretion disks can simultaneously exhibit MRI-driven MHD turbulence along with magneto-centrifugally accelerated outflows. However, in contradiction with previously published results, such outflows probably have little impact on the disk dynamics.

  1. Fibroblast growth factor (Fgf) 21 is a novel target gene of the aryl hydrocarbon receptor (AhR).

    PubMed

    Cheng, Xingguo; Vispute, Saurabh G; Liu, Jie; Cheng, Christine; Kharitonenkov, Alexei; Klaassen, Curtis D

    2014-07-01

    The toxic effects of dioxins, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), mainly through activation of the aryl hydrocarbon receptor (AhR) are well documented. Fibroblast growth factor (Fgf) 21 plays critical roles in metabolic adaptation to fasting by increasing lipid oxidation and ketogenesis in the liver. The present study was performed to determine whether activation of the AhR induces Fgf21 expression. In mouse liver, TCDD increased Fgf21 mRNA in both dose- and time-dependent manners. In addition, TCDD markedly increased Fgf21 mRNA expression in cultured mouse and human hepatocytes. Moreover, TCDD increased mRNA (in liver) and protein levels (in both liver and serum) of Fgf21 in wild-type mice, but not in AhR-null mice. Chromatin immunoprecipitation assays showed that TCDD increased AhR protein binding to the Fgf21 promoter (-105/+1 base pair). Fgf21-null mice administered 200μg/kg of TCDD died within 20days, whereas wild-type mice receiving the same treatment were still alive at one month after administration. This indicates that TCDD-induced Fgf21 expression protects against TCDD toxicity. Diethylhexylphthalate (DEHP) pretreatment attenuated TCDD-induced Fgf21 expression in mouse liver and white adipose tissue, which may explain a previous report that DEHP pretreatment decreases TCDD-induced wasting. In conclusion, Fgf21 appears to be a target gene of AhR-signaling pathway in mouse and human liver.

  2. Fibroblast growth factor (Fgf) 21 is a novel target gene of the aryl hydrocarbon receptor (AhR).

    PubMed

    Cheng, Xingguo; Vispute, Saurabh G; Liu, Jie; Cheng, Christine; Kharitonenkov, Alexei; Klaassen, Curtis D

    2014-07-01

    The toxic effects of dioxins, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), mainly through activation of the aryl hydrocarbon receptor (AhR) are well documented. Fibroblast growth factor (Fgf) 21 plays critical roles in metabolic adaptation to fasting by increasing lipid oxidation and ketogenesis in the liver. The present study was performed to determine whether activation of the AhR induces Fgf21 expression. In mouse liver, TCDD increased Fgf21 mRNA in both dose- and time-dependent manners. In addition, TCDD markedly increased Fgf21 mRNA expression in cultured mouse and human hepatocytes. Moreover, TCDD increased mRNA (in liver) and protein levels (in both liver and serum) of Fgf21 in wild-type mice, but not in AhR-null mice. Chromatin immunoprecipitation assays showed that TCDD increased AhR protein binding to the Fgf21 promoter (-105/+1 base pair). Fgf21-null mice administered 200μg/kg of TCDD died within 20days, whereas wild-type mice receiving the same treatment were still alive at one month after administration. This indicates that TCDD-induced Fgf21 expression protects against TCDD toxicity. Diethylhexylphthalate (DEHP) pretreatment attenuated TCDD-induced Fgf21 expression in mouse liver and white adipose tissue, which may explain a previous report that DEHP pretreatment decreases TCDD-induced wasting. In conclusion, Fgf21 appears to be a target gene of AhR-signaling pathway in mouse and human liver. PMID:24769090

  3. Shaping the outflows of evolved stars

    NASA Astrophysics Data System (ADS)

    Mohamed, Shazrene

    2015-08-01

    Both hot and cool evolved stars, e.g., red (super)giants and Wolf-Rayet stars, lose copious amounts of mass, momentum and mechanical energy through powerful, dense stellar winds. The interaction of these outflows with their surroundings results in highly structured and complex circumstellar environments, often featuring knots, arcs, shells and spirals. Recent improvements in computational power and techniques have led to the development of detailed, multi-dimensional simulations that have given new insight into the origin of these structures, and better understanding of the physical mechanisms driving their formation. In this talk, I will discuss three of the main mechanisms that shape the outflows of evolved stars:- interaction with the interstellar medium (ISM), i.e., wind-ISM interactions- interaction with a stellar wind, either from a previous phase of evolution or the wind from a companion star, i.e., wind-wind interactions- and interaction with a companion star that has a weak or insignicant outflow (e.g., a compact companion such as a neutron star or black hole), i.e., wind-companion interactions.I will also highlight the broader implications and impact of these stellar wind interactions for other phenomena, e.g, for symbiotic and X-ray binaries, supernovae and Gamma-ray bursts.

  4. Outflows of stars due to quasar feedback

    NASA Astrophysics Data System (ADS)

    Zubovas, Kastytis; Nayakshin, Sergei; Sazonov, Sergey; Sunyaev, Rashid

    2013-05-01

    Quasar feedback outflows are commonly invoked to drive gas out of galaxies in the early gas-rich epoch to terminate growth of galaxies. Here we present simulations that show that AGN feedback may drive not only gas but also stars out of their host galaxies under certain conditions. The mechanics of this process is as follows: (1) AGN-driven outflows accelerate and compress gas filling the host galaxy; (2) the accelerated dense shells become gravitationally unstable and form stars on radial trajectories. For the spherically symmetric initial conditions explored here, the black hole needs to exceed the host's Mσ mass by a factor of a few to accelerate the shells and the new stars to escape velocities. We discuss potential implications of these effects for the host galaxies: (i) radial mixing of bulge stars with the rest of the host; (ii) contribution of quasar outflows to galactic fountains as sources of high-velocity clouds; (iii) wholesale ejection of hypervelocity stars out of their hosts, giving rise to Type II supernovae on galactic outskirts, and contributing to reionization and metal enrichment of the Universe; (iv) bulge erosion and even complete destruction in extreme cases resulting in overweight or bulgeless SMBHs.

  5. NOAA 26.5 Ah LEO characterization test

    NASA Technical Reports Server (NTRS)

    Morrow, G. W.

    1986-01-01

    The General Electric (GE) 26.5 Ah NOAA-G flight nickel-cadmium cells were obtained from RCA-Astro Electronics to undergo performance characterization testing at the Goddard Space Flight Center (GSFC). This lot of cells was manufactured with passivated positive plate, to control nickel structure attack duing active material impregnation, and less electrolyte than normal (less than 3cc/Ah). The cells were tested in a parametric low Earth orbit (LEO) cycling regime that was previously used to test and characterize standard 50 Ah cells. Life cycle testing at the Naval Weapons Support Center (NWSC), in Crane, followed. The results of the test showed nominal performance in comparison with previous test data on the standard 50. Life cycle testing in the NOAA orbital regime is continuing at NWSC.

  6. BAL OUTFLOW CONTRIBUTION TO AGN FEEDBACK: FREQUENCY OF S IV OUTFLOWS IN THE SDSS

    SciTech Connect

    Dunn, Jay P.; Arav, Nahum; Laughlin, Courtney; Edmonds, Doug; Aoki, Kentaro; Wilkins, Ashlee; Bautista, Manuel E-mail: arav@vt.edu E-mail: kentaro.aoki@hawaiiantel.net E-mail: manuel.bautista@wmich.edu

    2012-05-10

    We present a study of broad absorption line (BAL) quasar outflows that show S IV {lambda}1063 and S IV* {lambda}1073 troughs. The fractional abundances of S IV and C IV peak at similar value of the ionization parameter, implying that they arise from the same physical component of the outflow. Detection of the S IV* troughs will allow us to determine the distance to this gas with higher resolution and higher signal-to-noise spectra, therefore providing the distance and energetics of the ubiquitous C IV BAL outflows. In our bright sample of 156 SDSS quasars, 14% show C IV and 1.9% S IV troughs, which are consistent with a fainter magnitude sample with twice as many objects. One object in the fainter sample shows evidence of a broad S IV trough without any significant trough present from the excited state line, which implies that this outflow could be at a distance of several kpc. Given the fractions of C IV and S IV, we establish firm limits on the global covering factor on S IV that ranges from 2.8% to 21% (allowing for the k-correction). Comparison of the expected optical depth for these ions with their detected percentage suggests that these species arise from common outflows with a covering factor closer to the latter.

  7. Transgenic Overexpression of Aryl Hydrocarbon Receptor Repressor (AhRR) and AhR-Mediated Induction of CYP1A1, Cytokines, and Acute Toxicity

    PubMed Central

    Vogel, Christoph F.A.; Chang, W.L. William; Kado, Sarah; McCulloh, Kelly; Vogel, Helena; Wu, Dalei; Haarmann-Stemmann, Thomas; Yang, GuoXiang; Leung, Patrick S.C.; Matsumura, Fumio; Gershwin, M. Eric

    2016-01-01

    Background: The aryl hydrocarbon receptor repressor (AhRR) is known to repress aryl hydrocarbon receptor (AhR) signaling, but very little is known regarding the role of the AhRR in vivo. Objective: This study tested the role of AhRR in vivo in AhRR overexpressing mice on molecular and toxic end points mediated through a prototypical AhR ligand. Methods: We generated AhRR-transgenic mice (AhRR Tg) based on the genetic background of C57BL/6J wild type (wt) mice. We tested the effect of the prototypical AhR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the expression of cytochrome P450 (CYP)1A1 and cytokines in various tissues of mice. We next analyzed the infiltration of immune cells in adipose tissue of mice after treatment with TCDD using flow cytometry. Results: AhRR Tg mice express significantly higher levels of AhRR compared to wt mice. Activation of AhR by TCDD caused a significant increase of the inflammatory cytokines Interleukin (IL)-1β, IL-6 and IL-10, and CXCL chemokines in white epididymal adipose tissue from both wt and AhRR Tg mice. However, the expression of IL-1β, CXCL2 and CXCL3 were significantly lower in AhRR Tg versus wt mice following TCDD treatment. Exposure to TCDD caused a rapid accumulation of neutrophils and macrophages in white adipose tissue of wt and AhRR Tg mice. Furthermore we found that male AhRR Tg mice were protected from high-dose TCDD-induced lethality associated with a reduced inflammatory response and liver damage as indicated by lower levels of TCDD-induced alanine aminotransferase and hepatic triglycerides. Females from both wt and AhRR Tg mice were less sensitive than male mice to acute toxicity induced by TCDD. Conclusion: In conclusion, the current study identifies AhRR as a previously uncharacterized regulator of specific inflammatory cytokines, which may protect from acute toxicity induced by TCDD. Citation: Vogel CF, Chang WL, Kado S, McCulloh K, Vogel H, Wu D, Haarmann-Stemmann T, Yang GX, Leung PS, Matsumura F

  8. Quasar feedback revealed by giant molecular outflows

    NASA Astrophysics Data System (ADS)

    Feruglio, C.; Maiolino, R.; Piconcelli, E.; Menci, N.; Aussel, H.; Lamastra, A.; Fiore, F.

    2010-07-01

    In the standard scenario for galaxy evolution young star-forming galaxies transform into red bulge-dominated spheroids, where star formation has been quenched. To explain this transformation, a strong negative feedback generated by accretion onto a central super-massive black hole is often invoked. The depletion of gas resulting from quasar-driven outflows should eventually stop star-formation across the host galaxy and lead the black hole to “suicide” by starvation. Direct observational evidence for a major quasar feedback onto the host galaxy is still missing, because outflows previously observed in quasars are generally associated with the ionized component of the gas, which only accounts for a minor fraction of the total gas content, and typically occurrs in the central regions. We used the IRAM PdB Interferometer to observe the CO(1-0) transition in Mrk 231, the closest quasar known. Thanks to the wide band we detected broad wings of the CO line, with velocities of up to 750 km s-1 and spatially resolved on the kpc scale. These broad CO wings trace a giant molecular outflow of about 700 M_⊙/year, far larger than the ongoing star-formation rate (~200 M_⊙/year) observed in the host galaxy. This wind will totally expel the cold gas reservoir in Mrk 231 in about 107 yrs, therefore halting the star-formation activity on the same timescale. The inferred kinetic energy in the molecular outflow is ~1.2 × 1044 erg/s, corresponding to a few percent of the AGN bolometric luminosity, which is very close to the fraction expected by models ascribing quasar feedback to highly supersonic shocks generated by radiatively accelerated nuclear winds. Instead, the contribution by the SNe associated with the starburst fall short by several orders of magnitude to account for the kinetic energy observed in the outflow. The direct observational evidence for quasar feedback reported here provides solid support to the scenarios ascribing the observed properties of local massive

  9. Design and Performance Data for 81 Ah FNC Cells

    NASA Technical Reports Server (NTRS)

    Cohen, F.; Anderman, Menahem

    1997-01-01

    Design and performance data for 81 Ah FNC cells are given. The conclusions are: that a sealed Ni-Cd cells are not limited to 50 Ah with the FNC design; energy densities of 40 Wh/kg in a conservative high Cd, high electrolyte design have been demonstrated; uniform ATP data and LEO cycling performance is being demonstrated; internal cell pressures remain low under all conditions; and no conditioning is necessary under any LEO profile; accelerated LEO cycling exhibits performance well beyond traditional space Ni-Cd cells.

  10. Anatomy of the Vestibulo-automatic Outflow to the Gut

    NASA Technical Reports Server (NTRS)

    Torigoe, Y.

    1985-01-01

    Motion sickness can be induced by vestibular effects on the sympathetic portion of the autonomic nervous system. However, the pathways linking the vestibular and autonomic pathways are unknown. As a first step in this analysis, the locations of preganglionic sympathetic neurons (PSN) and dorsal root afferent ganglionic neurons (DRG) which supply sympathetic innervation to major portions of the gastrointestinal tract in rabbits were identified. The objective of a second series of experiments is to determine which of the brainstem nuclei project to the autonomic regions of the spinal cord that control gastrointestinal motility. To achieve this goal, a trans-synaptic retrograde tracer (3H-tetanus toxoid) is applied to the greater splanchnic nerve. This method allows the labeling of neurons within the brainstem that project only to the preganglionic synpathetic neurons. One structure that has been strongly implicated in mediating vestibulo-autonomic control is the cerebellum (i.e., nodulus and uvula). The outflow of these lobules to the autonomic regions of the brainstem is mediated by the fastigial nucleus. To determine the precise projections of the fastigial nucleus to the brainstem nuclei involved in emesis, anterograde tracer (3H-leucine) was injected into the fastigial nucleus in a third series of experiments.

  11. The Prevalence of Gas Outflows in Type 2 AGNs. II. 3D Biconical Outflow Models

    NASA Astrophysics Data System (ADS)

    Bae, Hyun-Jin; Woo, Jong-Hak

    2016-09-01

    We present 3D models of biconical outflows combined with a thin dust plane for investigating the physical properties of the ionized gas outflows and their effect on the observed gas kinematics in type 2 active galactic nuclei (AGNs). Using a set of input parameters, we construct a number of models in 3D and calculate the spatially integrated velocity and velocity dispersion for each model. We find that three primary parameters, i.e., intrinsic velocity, bicone inclination, and the amount of dust extinction, mainly determine the simulated velocity and velocity dispersion. Velocity dispersion increases as the intrinsic velocity or the bicone inclination increases, while velocity (i.e., velocity shifts with respect to systemic velocity) increases as the amount of dust extinction increases. Simulated emission-line profiles well reproduce the observed [O iii] line profiles, e.g., narrow core and broad wing components. By comparing model grids and Monte Carlo simulations with the observed [O iii] velocity-velocity dispersion distribution of ˜39,000 type 2 AGNs, we constrain the intrinsic velocity of gas outflows ranging from ˜500 to ˜1000 km s-1 for the majority of AGNs, and up to ˜1500-2000 km s-1 for extreme cases. The Monte Carlo simulations show that the number ratio of AGNs with negative [O iii] velocity to AGNs with positive [O iii] velocity correlates with the outflow opening angle, suggesting that outflows with higher intrinsic velocity tend to have wider opening angles. These results demonstrate the potential of our 3D models for studying the physical properties of gas outflows, applicable to various observations, including spatially integrated and resolved gas kinematics.

  12. The Prevalence of Gas Outflows in Type 2 AGNs. II. 3D Biconical Outflow Models

    NASA Astrophysics Data System (ADS)

    Bae, Hyun-Jin; Woo, Jong-Hak

    2016-09-01

    We present 3D models of biconical outflows combined with a thin dust plane for investigating the physical properties of the ionized gas outflows and their effect on the observed gas kinematics in type 2 active galactic nuclei (AGNs). Using a set of input parameters, we construct a number of models in 3D and calculate the spatially integrated velocity and velocity dispersion for each model. We find that three primary parameters, i.e., intrinsic velocity, bicone inclination, and the amount of dust extinction, mainly determine the simulated velocity and velocity dispersion. Velocity dispersion increases as the intrinsic velocity or the bicone inclination increases, while velocity (i.e., velocity shifts with respect to systemic velocity) increases as the amount of dust extinction increases. Simulated emission-line profiles well reproduce the observed [O iii] line profiles, e.g., narrow core and broad wing components. By comparing model grids and Monte Carlo simulations with the observed [O iii] velocity–velocity dispersion distribution of ∼39,000 type 2 AGNs, we constrain the intrinsic velocity of gas outflows ranging from ∼500 to ∼1000 km s‑1 for the majority of AGNs, and up to ∼1500–2000 km s‑1 for extreme cases. The Monte Carlo simulations show that the number ratio of AGNs with negative [O iii] velocity to AGNs with positive [O iii] velocity correlates with the outflow opening angle, suggesting that outflows with higher intrinsic velocity tend to have wider opening angles. These results demonstrate the potential of our 3D models for studying the physical properties of gas outflows, applicable to various observations, including spatially integrated and resolved gas kinematics.

  13. Mass Outflow in the Narrow Line Region of Markarian 573

    NASA Astrophysics Data System (ADS)

    Revalski, Mitchell; Crenshaw, D. Michael; Fischer, Travis C.; Kraemer, Steven B.; Schmitt, Henrique R.

    2016-01-01

    We present our progress toward determining the mass outflow rate in the narrow emission line region (NLR) of the Seyfert 2 galaxy Markarian 573. Mass outflows in Active Galactic Nuclei (AGN) drive gas away from the central supermassive black hole (SMBH) into the circumnuclear environment, and may play an important role in regulating the growth of the SMBH, and its coevolution with the host galaxy bulge. Recent work by Crenshaw et al. (2015, ApJ, 799, 83) found that the mass outflow rate in the NLR of NGC 4151 is too large for the outflowing mass to have originated only from the central region, indicating a significant amount of gas is picked up by the outflow as it travels away from the nucleus. Using archival spectra taken with the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS), we are working to determine the mass outflow rates in a sample of 10 Seyfert galaxies to determine if correlations exist between their outflows and other properties including galaxy luminosity. To accomplish this, we will analyze the emission line spectra using photoionization models to determine the mass of the outflowing gas. Combining this information with previous kinematic modeling from Fischer et al. (2013, ApJS, 209, 1), we can determine the mass outflow rates and kinetic luminosities as a function of radius from the nucleus. These quantities will provide a direct comparison between observation and theoretical feedback models, allowing us to determine the significance of these outflows in regulating AGN feedback.

  14. CCD Photometric Study and Period Investigation of AH Tauri

    NASA Astrophysics Data System (ADS)

    Xiang, Fu-Yuan; Xiao, Ting-Yu; Yu, Yun-Xia

    2015-07-01

    In this paper, we present new CCD photometric observations of AH Tauri in the R band observed in 2006 at the Yunnan Observatory. Two new times of light minima were derived from these observations. We modeled the light curves using the 2003 version of the Wilson-Devinney program. The results show that the variations of the light curves can be expained by a cool spot on the primary star. The fill-out factor is about 6.6%, indicating that AH Tauri is a shallow-contact system. The mass ratio was determined to be about 0.505. In addition, the orbital period variations of AH Tauri were investigated based on all of the photoelectric and CCD light minimum times, including our two new data. It was found that the orbital period exhibits a possible periodic variation with a period of {P}{mod}=54.62\\(+/- 0.20) years and a secular period decrease of {dP}/{dt}=-(1.823+/- 0.215)× {10}-7 {days} {{yr}}-1. Since AH Tauri is an overcontact solar-like system, we discuss three mechanisms of the mass transfer, the light-time effect of the third body, and magnetic activity responsible for the orbital period changes.

  15. PESTICIDE TRADE NAMES AND THEIR ACTIVE INGREDIENTS IN THE AHS

    EPA Science Inventory

    The detailed information on the use of specific pesticides is a major strength of exposure assessment conducted for the Agricultural Health Study (AHS). During the enrollment interviews, a check list was used to collect information on the frequency and duration of use for 28 p...

  16. On the origin of pronounced O3 gradients in the thunderstorm outflow region during DC3

    NASA Astrophysics Data System (ADS)

    Huntrieser, H.; Lichtenstern, M.; Scheibe, M.; Aufmhoff, H.; Schlager, H.; Pucik, T.; Minikin, A.; Weinzierl, B.; Heimerl, K.; Fütterer, D.; Rappenglück, B.; Ackermann, L.; Pickering, K. E.; Cummings, K. A.; Biggerstaff, M. I.; Betten, D. P.; Honomichl, S.; Barth, M. C.

    2016-06-01

    Unique in situ measurements of CO, O3, SO2, CH4, NO, NOx, NOy, VOC, CN, and rBC were carried out with the German Deutsches Zentrum für Luft- und Raumfahrt (DLR)-Falcon aircraft in the central U.S. thunderstorms during the Deep Convective Clouds and Chemistry experiment in summer 2012. Fresh and aged anvil outflow (9-12 km) from supercells, mesoscale convective systems, mesoscale convective complexes, and squall lines were probed over Oklahoma, Texas, Colorado, and Kansas. For three case studies (30 May and 8 and 12 June) a combination of trace species, radar, lightning, and satellite information, as well as model results, were used to analyze and design schematics of major trace gas transport pathways within and in the vicinity of the probed thunderstorms. The impact of thunderstorms on the O3 composition in the upper troposphere/lower stratosphere (LS) region was analyzed. Overshooting cloud tops injected high amounts of biomass burning and lightning-produced NOx emissions into the LS, in addition to low O3 mixing ratios from the lower troposphere. As a dynamical response, O3-rich air from the LS was transported downward into the anvil and also surrounded the outflow. The ΔO3/ΔCO ratio was determined in the anvil outflow region. A pronounced in-mixing of O3-rich stratospheric air masses was observed in the outflow indicated by highly positive or even negative ΔO3/ΔCO ratios (+1.4 down to -3.9). Photochemical O3 production (ΔO3/ΔCO = +0.1) was found to be minor in the recently lofted pollution plumes. O3 mixing ratios within the aged anvil outflow were mainly enhanced due to dynamical processes.

  17. Evidence for Collimated Outflow from Sgr A*?

    NASA Astrophysics Data System (ADS)

    Yusef-Zadeh, Farhad; Arendt, R.; Bushouse, H.; Cotton, W.; Haggard, D.; Heinke, C.; Roberts, D. A.; Royster, M.; Wardle, M.

    2012-05-01

    The compact radio source Sgr A* is considered to be coincident with a 4 million solar mass black hole at the dynamical center of the Galaxy. There has been a considerable debate as to whether the jet or the accretion flow model can explain the broad band spectrum of the emission. Here, we present high resolution radio, X-ray continuum and FeII line images showing new structural details within the inner arcminute (2.4pc) of Sgr A*. On a small scale, we find a chain of radio blobs which appear to be emanating from Sgr A*. These blobs are detected beyond the inner 1" of Sgr A* and are distributed along a continuous linear feature that is tilted by 28 degrees with respect to the Galactic plane. In linear polarization images at 3.6cm, three blobs of emission have been detected symmetrically about 1' from Sgr A*. The morphology and polarization of the linear feature suggest a jet outflow from Sgr A*, punching through the orbiting ionized gas and producing X-ray emission as well as a hot bubble of FeIII/FeII line emission. On a scale of about 15pc, we also note a collection of large-scale radio and X-ray "streamers" in the direction perpendicular to the Galactic plane. This complex structure consists of nonthermal and thermal continuum features as well as molecular clouds traced at infrared wavelengths. The base of the outflowing gas appears to be confined by the 2-pc molecular ring, within which a cluster of massive stars lie. These features suggest star-burst driven outflow may be responsible for this energetic activity.

  18. Functional Anatomy of the Outflow Facilities.

    PubMed

    Pizzirani, Stefano; Gong, Haiyan

    2015-11-01

    In order to understand the pathophysiology, select optimal therapeutic options for patients and provide clients with honest expectations for cases of canine glaucoma, clinicians should be familiar with a rational understanding of the functional anatomy of the ocular structures involved in this group of diseases. The topographical extension and the structural and humoral complexity of the regions involved with the production and the outflow of aqueous humor undergo numerous changes with aging and disease. Therefore, the anatomy relative to the fluid dynamics of aqueous has become a pivotal yet flexible concept to interpret the different phenotypes of glaucoma.

  19. Valles Marineris and Chryse Outflow Channels

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A color image of Valles Marineris, the great canyon and the south Chryse basin-Valles Marineris outflow channels of Mars; north toward top. The scene shows the entire Valles Marineris canyon system, over 3,000 km long and averaging 8 km deep, extending from Noctis Labyrinthus, the arcuate system of graben to the west, to the chaotic terrain to the east and related outflow canyons that drain toward the Chryse basin. Eos and Capri Chasmata (south to north) are two canyons connected to Valles Marineris. Ganges Chasma lies directly north. The chaos in the southeast part of the image gives rise to several outflow channels, Shalbatana, Simud, Tiu, and Ares Valles (left to right), that drained north into the Chryse basin. The mouth of Ares Valles is the site of the Mars Pathfinder lander.

    This image is a composite of Viking medium-resolution images in black and white and low-resolution images in color; Mercator projection. The image roughly extends from latitude 20 degrees S. to 20 degrees N. and from longitude 15 degrees to 102.5 degrees.

    The connected chasma or valleys of Valles Marineris may have formed from a combination of erosional collapse and structural activity. Layers of material in the eastern canyons might consist of carbonates deposited in ancient lakes, eolian deposits, or volcanic materials. Huge ancient river channels began from Valles Marineris and from adjacent canyons and ran north. Many of the channels flowed north into Chryse Basin.

    The south Chryse outflow channels are cut an average of 1 km into the cratered highland terrain. This terrain is about 9 km above datum near Valles Marineris and steadily decreases in elevation to 1 km below datum in the Chryse basin. Shalbatana is relatively narrow (10 km wide) but can reach 3 km in depth. The channel begins at a 2- to 3-km-deep circular depression within a large impact crater, whose floor is partly covered by chaotic material, and ends in Simud Valles. Tiu and Simud Valles consist of a

  20. ATOMIC HYDROGEN IN A GALACTIC CENTER OUTFLOW

    SciTech Connect

    McClure-Griffiths, N. M.; Green, J. A.; Hill, A. S.; Lockman, F. J.; Dickey, J. M.; Gaensler, B. M.; Green, A. J.

    2013-06-10

    We describe a population of small, high-velocity, atomic hydrogen clouds, loops, and filaments found above and below the disk near the Galactic center. The objects have a mean radius of 15 pc, velocity widths of {approx}14 km s{sup -1}, and are observed at |z| heights up to 700 pc. The velocity distribution of the clouds shows no signature of Galactic rotation. We propose a scenario where the clouds are associated with an outflow from a central star-forming region at the Galactic center. We discuss the clouds as entrained material traveling at {approx}200 km s{sup -1} in a Galactic wind.

  1. Feedback Mechanisms of Starbursts and AGNs through Molecular Outflows

    NASA Astrophysics Data System (ADS)

    Matsushita, S.; Krips, M.; Lim, J.; Muller, S.; Tsai, A.-L.

    2013-10-01

    Our deep molecular line images of nearby starburst galaxies and AGNs exhibit molecular outflows in most galaxies, and have revealed that the molecular outflows co-exist with outflows or jets seen in other wavelengths. In case of starbursts, X-ray outflows have higher energy and pressure than those of molecular outflows, suggesting that plasma outflows are blowing the molecular gas away from starburst regions, which suggests a strong negative feedback. On the other hand, current starburst regions in M82 can be seen at the inner edge of an expanding molecular bubble, suggesting a positive feedback. In case of AGNs, jets seem to entrain the surrounding molecular gas away from the AGNs, suggesting a negative feedback.

  2. A resolved outflow of matter from a brown dwarf.

    PubMed

    Whelan, Emma T; Ray, Thomas P; Bacciotti, Francesca; Natta, Antonella; Testi, Leonardo; Randich, Sofia

    2005-06-01

    The birth of stars involves not only accretion but also, counter-intuitively, the expulsion of matter in the form of highly supersonic outflows. Although this phenomenon has been seen in young stars, a fundamental question is whether it also occurs among newborn brown dwarfs: these are the so-called 'failed stars', with masses between stars and planets, that never manage to reach temperatures high enough for normal hydrogen fusion to occur. Recently, evidence for accretion in young brown dwarfs has mounted, and their spectra show lines that are suggestive of outflows. Here we report spectro-astrometric data that spatially resolve an outflow from a brown dwarf. The outflow's characteristics appear similar to, but on a smaller scale than, outflows from normal young stars. This result suggests that the outflow mechanism is universal, and perhaps relevant even to the formation of planets.

  3. TRACING THE BIPOLAR OUTFLOW FROM ORION SOURCE I

    SciTech Connect

    Plambeck, R. L.; Wright, M. C. H.; Friedel, D. N.; Widicus Weaver, S. L.; Bolatto, A. D.; Pound, M. W.; Woody, D. P.; Lamb, J. W.; Scott, S. L.

    2009-10-10

    Using CARMA, we imaged the 87 GHz SiO v = 0 J = 2-1 line toward Orion-KL with 0.''45 angular resolution. The maps indicate that radio source I drives a bipolar outflow into the surrounding molecular cloud along a NE-SW axis, in agreement with the model of Greenhill et al. The extended high-velocity outflow from Orion-KL appears to be a continuation of this compact outflow. High-velocity gas extends farthest along a NW-SE axis, suggesting that the outflow direction changes on timescales of a few hundred years.

  4. Suppression of galactic outflows by cosmological infall and circumgalactic medium

    NASA Astrophysics Data System (ADS)

    Singh, Priyanka; Rana, Sandeep; Bagla, Jasjeet S.; Nath, Biman B.

    2016-06-01

    We investigate the relative importance of two galactic outflow suppression mechanisms: (a) cosmological infall of the intergalactic gas on to the galaxy, and (b) the existence of a hot circumgalactic medium (CGM). Considering only radial motion, the infall reduces the speed of outflowing gas and even halts the outflow, depending on the mass and redshift of the galaxy. For star-forming galaxies, there exists an upper mass limit beyond which outflows are suppressed by the gravitational field of the galaxy. We find that infall can reduce this upper mass limit approximately by a factor of 2 (independent of the redshift). Massive galaxies (≳1012 M⊙) host large reservoir of hot, diffuse CGM around the central part of the galaxy. The CGM acts as a barrier between the infalling and outflowing gas and provides an additional source of outflow suppression. We find that at low redshifts (z ≲ 3.5), the CGM is more effective than the infall in suppressing the outflows. Together, these two processes give a mass range in which galaxies are unable to have effective outflows. We also discuss the impact of outflow suppression on the enrichment history of the galaxy and its environment.

  5. ALMA OBSERVATIONS OF THE HH 46/47 MOLECULAR OUTFLOW

    SciTech Connect

    Arce, Hector G.; Mardones, Diego; Garay, Guido; Corder, Stuartt A.; Noriega-Crespo, Alberto; Raga, Alejandro C.

    2013-09-01

    The morphology, kinematics, and entrainment mechanism of the HH 46/47 molecular outflow were studied using new ALMA Cycle 0 observations. Results show that the blue and red lobes are strikingly different. We argue that these differences are partly due to contrasting ambient densities that result in different wind components having a distinct effect on the entrained gas in each lobe. A 29 point mosaic, covering the two lobes at an angular resolution of about 3'', detected outflow emission at much higher velocities than previous observations, resulting in significantly higher estimates of the outflow momentum and kinetic energy than previous studies of this source, using the CO(1-0) line. The morphology and the kinematics of the gas in the blue lobe are consistent with models of outflow entrainment by a wide-angle wind, and a simple model describes the observed structures in the position-velocity diagram and the velocity-integrated intensity maps. The red lobe exhibits a more complex structure, and there is evidence that this lobe is entrained by a wide-angle wind and a collimated episodic wind. Three major clumps along the outflow axis show velocity distribution consistent with prompt entrainment by different bow shocks formed by periodic mass ejection episodes which take place every few hundred years. Position-velocity cuts perpendicular to the outflow cavity show gradients where the velocity increases toward the outflow axis, inconsistent with outflow rotation. Additionally, we find evidence for the existence of a small outflow driven by a binary companion.

  6. Characterizing Quasar Outflows II: The Incidence of the Highest Velocity Outflows

    NASA Astrophysics Data System (ADS)

    Stark, Michele A.; Ganguly, R.; Christenson, D. H.; Richmond, J. M.; Derseweh, J. A.; Robbins, J. M.; Townsend, S. L.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In an accompanying poster, we subjectively divide these quasars into four categories (broad absorption-line quasars, associated absorption-line quasars, reddened quasars, and unabsorbed/unreddened quasars). This subjective scheme is limited with regard to classifying narrow absorption-line systems (NALs). With single epoch, low dispersion SDSS spectra, we cannot distinguish between cosmologically intervening NALs, and intrinsic NALs that appear at large velocity offsets. In this poster, we tackle this uncertainty statistically by considering the incidence of both CIV and MgII NALs as a function of velocity, and how this distribution changes with quasar properties. We expect that absorption by intervening structures should not vary with quasar property. Other accompanying posters add photometry from rest-frame X-ray through the infrared (WISE) to complete the SED, which we utilize in these efforts. This material is based upon work supported by the National Aeronautics and Space Administration under

  7. Transparency parameters from relativistically expanding outflows

    SciTech Connect

    Bégué, D.; Iyyani, S.

    2014-09-01

    In many gamma-ray bursts a distinct blackbody spectral component is present, which is attributed to the emission from the photosphere of a relativistically expanding plasma. The properties of this component (temperature and flux) can be linked to the properties of the outflow and have been presented in the case where there is no sub-photospheric dissipation and the photosphere is in coasting phase. First, we present the derivation of the properties of the outflow for finite winds, including when the photosphere is in the accelerating phase. Second, we study the effect of localized sub-photospheric dissipation on the estimation of the parameters. Finally, we apply our results to GRB 090902B. We find that during the first epoch of this burst the photosphere is most likely to be in the accelerating phase, leading to smaller values of the Lorentz factor than the ones previously estimated. For the second epoch, we find that the photosphere is likely to be in the coasting phase.

  8. Magnetospheric and Thermospheric Influence on Ionospheric Outflow

    NASA Astrophysics Data System (ADS)

    Garcia-Sage, K.; Moore, T. E.; Mitchell, E. J.; Olson, D. K.

    2013-12-01

    The Fast Auroral SnapshoT (FAST) small explorer has been used extensively to study ionospheric outflow. Past research has used particle and field data to examine the contemporaneous transfer of electromagnetic energy and particle flow downward from the magnetosphere and upward from the ionosphere. Single event studies published by Strangeway et al. [2005] and Brambles et al. [2011, Supporting Online Material] showed that downward electromagnetic energy and particle flow into the ionosphere are correlated with the upward flow of ions out of the ionosphere. It is expected, however, that this correlation will be affected by circumstances that are unique to each specific event, including but not limited to the outflow location (cusp or nightside), preconditioning due to prior geomagnetic activity, and thermospheric neutral densities. Although knowledge of the thermospheric neutral density is usually unavailable, data from the CHAllenging Minisatellite Payload (CHAMP) is able to provide insight into thermospheric populations at altitudes of about 400 km for a few select events. We expand on the previously-mentioned studies by looking at FAST particle and field data for additional events, and we further examine the influence of thermospheric neutral populations, based on CHAMP data.

  9. IONIZED OUTFLOWS FROM COMPACT STEEP SPECTRUM SOURCES

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan; Kewley, Lisa E-mail: stockton@ifa.hawaii.edu

    2013-08-01

    Massive outflows are known to exist, in the form of extended emission-line regions (EELRs), around about one-third of powerful FR II radio sources. We investigate the origin of these EELRs by studying the emission-line regions around compact-steep-spectrum (CSS) radio galaxies that are younger (10{sup 3}-10{sup 5} yr old) versions of the FR II radio galaxies. We have searched for and analyzed the emission-line regions around 11 CSS sources by taking integral field spectra using Gemini Multi-Object Spectrograph on Gemini North. We fit the [O III] {lambda}5007 line and present the velocity maps for each detected emission-line region. We find, in most cases, that the emission-line regions have multi-component velocity structures with different velocity dispersions and/or flux distributions for each component. The velocity gradients of the emission-line gas are mostly well aligned with the radio axis, suggesting a direct causal link between the outflowing gas and the radio jets. The complex velocity structure may be a result of different driving mechanisms related to the onset of the radio jets. We also present the results from the line-ratio diagnostics we used to analyze the ionization mechanism of the extended gas, which supports the scenario where the emission-line regions are ionized by a combination of active galactic nucleus radiation and shock excitation.

  10. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure of normal human dermal fibroblasts results in AhR-dependent and -independent changes in gene expression

    SciTech Connect

    Akintobi, A.M.; Villano, C.M.; White, L.A. . E-mail: lawhite@aesop.rutgers.edu

    2007-04-01

    Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) results in a variety of lesions in mammals including severe skin lesions. The majority of TCDD's biological effects are mediated through activation of the aryl hydrocarbon receptor (AhR). We have chosen to examine the effect of TCDD and the AhR pathway on dermal fibroblasts because this cell type plays an integral role in skin homeostasis through the production of cytokines and other factors that regulate epidermal proliferation and differentiation. Our data show that normal human dermal fibroblasts (NHDFs) are responsive to TCDD, as demonstrated by induction of cytochrome p450 1B1 (CYP1B1) expression. Further, our data demonstrate that TCDD treatment of NHDFs results in significant (75-90%) decrease in expression of Id-1 and Id-3, proteins that are involved in regulation of cell proliferation and differentiation. The Id (Inhibitor of DNA binding) proteins are transcriptional inhibitors that function by forming inactive heterodimers with other HLH proteins. TCDD-repression of Id-1 and -3 is independent of de novo protein synthesis; co-treatment with cycloheximide has no effect on TCDD inhibition of Id-1 and Id-3. Co-treatment with the AhR antagonist {alpha}-naphthoflavone also does not block inhibition of Id-1 and Id-3 by TCDD, suggesting that TCDD inhibition of Id-1 and Id-3 is, at least in part, mediated independently of the AhR pathway. Our data also show that TCDD inhibits expression of the cell cycle regulatory gene p16{sup ink4a}, which is often linked to Id expression. TCDD-induced reduction of p16{sup ink4a} expression is also independent of protein synthesis and the AhR pathway.

  11. LPS-TLR4 Pathway Mediates Ductular Cell Expansion in Alcoholic Hepatitis

    PubMed Central

    Odena, Gemma; Chen, Jiegen; Lozano, Juan Jose; Altamirano, Jose; Rodrigo-Torres, Daniel; Affo, Silvia; Morales-Ibanez, Oriol; Matsushita, Hiroshi; Zou, Jian; Dumitru, Raluca; Caballeria, Juan; Gines, Pere; Arroyo, Vicente; You, Min; Rautou, Pierre-Emmanuel; Valla, Dominique; Crews, Fulton; Seki, Ekihiro; Sancho-Bru, Pau; Bataller, Ramon

    2016-01-01

    Alcoholic hepatitis (AH) is the most severe form of alcoholic liver disease for which there are no effective therapies. Patients with AH show impaired hepatocyte proliferation, expansion of inefficient ductular cells and high lipopolysaccharide (LPS) levels. It is unknown whether LPS mediates ductular cell expansion. We performed transcriptome studies and identified keratin 23 (KRT23) as a new ductular cell marker. KRT23 expression correlated with mortality and LPS serum levels. LPS-TLR4 pathway role in ductular cell expansion was assessed in human and mouse progenitor cells, liver slices and liver injured TLR4 KO mice. In AH patients, ductular cell expansion correlated with portal hypertension and collagen expression. Functional studies in ductular cells showed that KRT23 regulates collagen expression. These results support a role for LPS-TLR4 pathway in promoting ductular reaction in AH. Maneuvers aimed at decreasing LPS serum levels in AH patients could have beneficial effects by preventing ductular reaction development. PMID:27752144

  12. Measurement of Outflow Facility Using iPerfusion

    PubMed Central

    Sherwood, Joseph M.; Reina-Torres, Ester; Bertrand, Jacques A.; Rowe, Barnaby; Overby, Darryl R.

    2016-01-01

    Elevated intraocular pressure (IOP) is the predominant risk factor for glaucoma, and reducing IOP is the only successful strategy to prevent further glaucomatous vision loss. IOP is determined by the balance between the rates of aqueous humour secretion and outflow, and a pathological reduction in the hydraulic conductance of outflow, known as outflow facility, is responsible for IOP elevation in glaucoma. Mouse models are often used to investigate the mechanisms controlling outflow facility, but the diminutive size of the mouse eye makes measurement of outflow technically challenging. In this study, we present a new approach to measure and analyse outflow facility using iPerfusion™, which incorporates an actuated pressure reservoir, thermal flow sensor, differential pressure measurement and an automated computerised interface. In enucleated eyes from C57BL/6J mice, the flow-pressure relationship is highly non-linear and is well represented by an empirical power law model that describes the pressure dependence of outflow facility. At zero pressure, the measured flow is indistinguishable from zero, confirming the absence of any significant pressure independent flow in enucleated eyes. Comparison with the commonly used 2-parameter linear outflow model reveals that inappropriate application of a linear fit to a non-linear flow-pressure relationship introduces considerable errors in the estimation of outflow facility and leads to the false impression of pressure-independent outflow. Data from a population of enucleated eyes from C57BL/6J mice show that outflow facility is best described by a lognormal distribution, with 6-fold variability between individuals, but with relatively tight correlation of facility between fellow eyes. iPerfusion represents a platform technology to accurately and robustly characterise the flow-pressure relationship in enucleated mouse eyes for the purpose of glaucoma research and with minor modifications, may be applied in vivo to mice, as

  13. Measurement of Outflow Facility Using iPerfusion.

    PubMed

    Sherwood, Joseph M; Reina-Torres, Ester; Bertrand, Jacques A; Rowe, Barnaby; Overby, Darryl R

    2016-01-01

    Elevated intraocular pressure (IOP) is the predominant risk factor for glaucoma, and reducing IOP is the only successful strategy to prevent further glaucomatous vision loss. IOP is determined by the balance between the rates of aqueous humour secretion and outflow, and a pathological reduction in the hydraulic conductance of outflow, known as outflow facility, is responsible for IOP elevation in glaucoma. Mouse models are often used to investigate the mechanisms controlling outflow facility, but the diminutive size of the mouse eye makes measurement of outflow technically challenging. In this study, we present a new approach to measure and analyse outflow facility using iPerfusion™, which incorporates an actuated pressure reservoir, thermal flow sensor, differential pressure measurement and an automated computerised interface. In enucleated eyes from C57BL/6J mice, the flow-pressure relationship is highly non-linear and is well represented by an empirical power law model that describes the pressure dependence of outflow facility. At zero pressure, the measured flow is indistinguishable from zero, confirming the absence of any significant pressure independent flow in enucleated eyes. Comparison with the commonly used 2-parameter linear outflow model reveals that inappropriate application of a linear fit to a non-linear flow-pressure relationship introduces considerable errors in the estimation of outflow facility and leads to the false impression of pressure-independent outflow. Data from a population of enucleated eyes from C57BL/6J mice show that outflow facility is best described by a lognormal distribution, with 6-fold variability between individuals, but with relatively tight correlation of facility between fellow eyes. iPerfusion represents a platform technology to accurately and robustly characterise the flow-pressure relationship in enucleated mouse eyes for the purpose of glaucoma research and with minor modifications, may be applied in vivo to mice, as

  14. Comparing introduction to Europe of highly pathogenic avian influenza viruses A(H5N8) in 2014 and A(H5N1) in 2005.

    PubMed

    Adlhoch, C; Gossner, C; Koch, G; Brown, I; Bouwstra, R; Verdonck, F; Penttinen, P; Harder, T

    2014-01-01

    Since the beginning of November 2014, nine outbreaks of highly pathogenic avian influenza virus (HPAIV) A(H5N8) in poultry have been detected in four European countries. In this report, similarities and differences between the modes of introduction of HPAIV A(H5N1) and A(H5N8) into Europe are described. Experiences from outbreaks of A(H5N1) in Europe demonstrated that early detection to control HPAIV in poultry has proven pivotal to minimise the risk of zoonotic transmission and prevention of human cases.

  15. Characterizing Quasar Outflows IV: Regulating Outflows Through X-ray and EUV Absorption

    NASA Astrophysics Data System (ADS)

    Derseweh, Jeffrey; Ganguly, R.; Richmond, J. M.; Stark, M. A.; Christenson, D. H.; Robbins, J. M.; Townsend, S. L.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In this poster, we add photometry from the GALEX All-sky imaging survey, as well as the Chandra and ROSAT archives. These provide coverage of the rest-frame extreme ultraviolet, and soft X-ray bands. In an accompanying poster, we have subjectively divided these quasars into four categories: broad absorption-line quasars (2700 objects), associated absorption-line quasars (1700 objects), reddened quasars (160 objects), and unabsorbed/unreddened quasars (6300 objects). We are interested in testing the radiative-driving hypothesis that requires a suppression of X-ray flux in order to transfer momentum efficiently to the UV-absorbing gas. Hence, we explore how absorption in both the extreme ultraviolet and the soft X-ray bands correlate with properties of the UV outflows, quasar property, and changes in SED shape. This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. 09-ADP09-0016 issued through the Astrophysics Data Analysis Program and by Chandra

  16. Measuring the seeds of thermal ion outflow

    NASA Astrophysics Data System (ADS)

    Fernandes, Philip A.

    The ionosphere is the primary source for heavy ions which are ubiquitous in the terrestrial magnetosphere. Low-altitude energization in the auroral ionosphere results in bulk heating and transverse acceleration of ions, which begin to upwell and/or be accelerated upward by the mirror force, starting upflow and leading to the outflow process. The details of the processes that seed ion outflow at low altitudes are difficult to measure in situ and thus remain an open question. We examine the observational parameter regime in which ion upflow/outflow initiates. Emphasis is placed on making measurements of the thermal ion kinetic distribution function, allowing for accounting of processes which affect in situ plasma measurements. We consider an electrostatic analyzer (ESA) instrument capable of making the measurements necessary to quantify the roles of various heating mechanisms in initiating ion upflow in the low-altitude auroral ionosphere. We present the difficulties associated with making these measurements and identify instrument design choices that mitigate some of these measurement challenges. Analysis of ESA measurements of the thermal ion distribution function taken on the MICA auroral sounding rocket is presented. Using a Maxwellian model to replicate possible measured spectra, we calculate integrated parameters from the model and compare with equivalent parameters calculated from the in situ data. Through Liouville's theorem and the thin-sheath approximation we couple the measured and forward-modeled parameters such that measurements inside the sheath provide information about the state of the plasma outside the sheath. Throughout the MICA flight, ion upflow is observed and attributed to ambipolar electric fields and/or ion-neutral interactions. Late in the flight we observe quasi-static frictional process driving the ion temperature. Early in the flight we observe ion heating weakly correlated with ELF wave activity; our analysis suggests we must consider

  17. TCDD promoted EMT of hFPECs via AhR, which involved the activation of EGFR/ERK signaling.

    PubMed

    Gao, Zhan; Bu, Yongjun; Liu, Xiaozhuan; Wang, Xugang; Zhang, Guofu; Wang, Erhui; Ding, Shibin; Liu, Yongfeng; Shi, Ruling; Li, Qiaoyun; Fu, Jianhong; Yu, Zengli

    2016-05-01

    One critical step of second palatal fusion is the newly formed medial epithelia seam (MES) disintegration, which involves apoptosis, epithelial to mesenchymal transition (EMT), and cell migration. Although the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces cleft palate at high rates, little is known about the effects of TCDD exposure on the fate of palatal epithelial cells. By using primary epithelial cells isolated from human fetal palatal shelves (hFPECs), we show that TCDD increased cell proliferation and EMT, as demonstrated by increased the epithelial markers (E-cadherin and cytokeratin14) and enhanced the mesenchymal markers (vimentin and fibronectin), but had no effect on cell migration and apoptosis. TCDD exposure led to a dose-dependent increase in Slug protein expression. Coimmunoprecipitation revealed that TCDD promoted AhR to form a protein complex with Slug. ChIP assay confirmed that TCDD exposure recruited AhR to the xenobiotic responsive element of Slug promoter. Knockdown of AhR by siRNA remarkably weakened TCDD-induced binding of AhR to the XRE promoter of slug, thereby suppressed TCDD-induced vimentin. Further experiment showed that TCDD stimulated EGFR phosphorylation did not influence the TGFβ3/Smad signaling; whereas TCDD increased phosphorylation of ERK1/2 and p38 with no effect on activation of JNK. By using varieties of inhibitors, we confirmed that TCDD promoted proliferation and EMT of hFPECs via activation of EGFR/ERK pathway. These data make a novel contribution to the molecular mechanism of cleft palate by TCDD. PMID:26971374

  18. An orbital period for the dwarf nova AH Herculis

    NASA Astrophysics Data System (ADS)

    Moffat, A. F. J.; Shara, M. M.

    1984-07-01

    AH Her is the best-studied dwarf nova which displays rapid coherent oscillations at maximum light, yet its orbital period is not determined. Eleven nights of observations with the 1-meter Wise Observatory telescope with chopping secondary, and 'Nather' photometer, yield a period P = 0.247 + or - 0.008 day, in excellent agreement with that predicted from the decline rate of the outburst. The source of flickering in the system (presumably the hot spot) is shown to fluctuate with the same amplitude whether AH Her is in outburst or not. The implication is that the accretion stream, hot spot, and outer disk are unaffected by, and do not take part in the eruption.

  19. Ketamine-mediated afferent-specific presynaptic transmission blocks in low-threshold and sex-specific subpopulation of myelinated Ah-type baroreceptor neurons of rats

    PubMed Central

    Wu, Di; Yin, Lei; Fan, Yao; Wang, Ye; Chen, Wei-Ran; Chen, Pei; Liu, Yang; Lu, Xiao-Long; Sun, Hong-Li; Shou, Weinian; Qiao, Guo-Fen; Li, Bai-Yan

    2015-01-01

    Background Ketamine enhances autonomic activity, and unmyelinated C-type baroreceptor afferents are more susceptible to be blocked by ketamine than myelinated A-types. However, the presynaptic transmission block in low-threshold and sex-specific myelinated Ah-type baroreceptor neurons (BRNs) is not elucidated. Methods Action potentials (APs) and excitatory post-synaptic currents (EPSCs) were investigated in BRNs/barosensitive neurons identified by conduction velocity (CV), capsaicin-conjugated with Iberiotoxin-sensitivity and fluorescent dye using intact nodose slice and brainstem slice in adult female rats. The expression of mRNA and targeted protein for NMDAR1 was also evaluated. Results Ketamine time-dependently blocked afferent CV in Ah-types in nodose slice with significant changes in AP discharge. The concentration-dependent inhibition of ketamine on AP discharge profiles were also assessed and observed using isolated Ah-type BRNs with dramatic reduction in neuroexcitability. In brainstem slice, the 2nd-order capsaicin-resistant EPSCs were identified and ∼50% of them were blocked by ketamine concentration-dependently with IC50 estimated at 84.4 μM compared with the rest (708.2 μM). Interestingly, the peak, decay time constant, and area under curve of EPSCs were significantly enhanced by 100 nM iberiotoxin in ketamine-more sensitive myelinated NTS neurons (most likely Ah-types), rather than ketamine-less sensitive ones (A-types). Conclusions These data have demonstrated, for the first time, that low-threshold and sex-specific myelinated Ah-type BRNs in nodose and Ah-type barosensitive neurons in NTS are more susceptible to ketamine and may play crucial roles in not only mean blood pressure regulation but also buffering dynamic changes in pressure, as well as the ketamine-mediated cardiovascular dysfunction through sexual-dimorphic baroreflex afferent pathway. PMID:26675761

  20. Confronting the outflow-regulated cluster formation model with observations

    SciTech Connect

    Nakamura, Fumitaka; Li, Zhi-Yun E-mail: zl4h@virginia.edu

    2014-03-10

    Protostellar outflows have been shown theoretically to be capable of maintaining supersonic turbulence in cluster-forming clumps and keeping the star formation rate per free-fall time as low as a few percent. We aim to test two basic predictions of this outflow-regulated cluster formation model, namely, (1) the clump should be close to virial equilibrium and (2) the turbulence dissipation rate should be balanced by the outflow momentum injection rate, using recent outflow surveys toward eight nearby cluster-forming clumps (B59, L1551, L1641N, Serpens Main Cloud, Serpens South, ρ Oph, IC 348, and NGC 1333). We find, for almost all sources, that the clumps are close to virial equilibrium and the outflow momentum injection rate exceeds the turbulence momentum dissipation rate. In addition, the outflow kinetic energy is significantly smaller than the clump gravitational energy for intermediate and massive clumps with M {sub cl} ≳ a few × 10{sup 2} M {sub ☉}, suggesting that the outflow feedback is not enough to disperse the clump as a whole. The number of observed protostars also indicates that the star formation rate per free-fall time is as small as a few percent for all clumps. These observationally based results strengthen the case for outflow-regulated cluster formation.

  1. Collective outflow from a small multiple stellar system

    SciTech Connect

    Peters, Thomas; Klaassen, Pamela D.; Mac Low, Mordecai-Mark; Schrön, Martin; Klessen, Ralf S.; Federrath, Christoph; Smith, Michael D.

    2014-06-10

    The formation of high-mass stars is usually accompanied by powerful protostellar outflows. Such high-mass outflows are not simply scaled-up versions of their lower-mass counterparts, since observations suggest that the collimation degree degrades with stellar mass. Theoretically, the origins of massive outflows remain open to question because radiative feedback and fragmentation of the accretion flow around the most massive stars, with M > 15 M {sub ☉}, may impede the driving of magnetic disk winds. We here present a three-dimensional simulation of the early stages of core fragmentation and massive star formation that includes a subgrid-scale model for protostellar outflows. We find that stars that form in a common accretion flow tend to have aligned outflow axes, so that the individual jets of multiple stars can combine to form a collective outflow. We compare our simulation to observations with synthetic H{sub 2} and CO observations and find that the morphology and kinematics of such a collective outflow resembles some observed massive outflows, such as Cepheus A and DR 21. We finally compare physical quantities derived from simulated observations of our models to the actual values in the models to examine the reliability of standard methods for deriving physical quantities, demonstrating that those methods indeed recover the actual values to within a factor of two to three.

  2. Confronting the Outflow-regulated Cluster Formation Model with Observations

    NASA Astrophysics Data System (ADS)

    Nakamura, Fumitaka; Li, Zhi-Yun

    2014-03-01

    Protostellar outflows have been shown theoretically to be capable of maintaining supersonic turbulence in cluster-forming clumps and keeping the star formation rate per free-fall time as low as a few percent. We aim to test two basic predictions of this outflow-regulated cluster formation model, namely, (1) the clump should be close to virial equilibrium and (2) the turbulence dissipation rate should be balanced by the outflow momentum injection rate, using recent outflow surveys toward eight nearby cluster-forming clumps (B59, L1551, L1641N, Serpens Main Cloud, Serpens South, ρ Oph, IC 348, and NGC 1333). We find, for almost all sources, that the clumps are close to virial equilibrium and the outflow momentum injection rate exceeds the turbulence momentum dissipation rate. In addition, the outflow kinetic energy is significantly smaller than the clump gravitational energy for intermediate and massive clumps with M cl >~ a few × 102 M ⊙, suggesting that the outflow feedback is not enough to disperse the clump as a whole. The number of observed protostars also indicates that the star formation rate per free-fall time is as small as a few percent for all clumps. These observationally based results strengthen the case for outflow-regulated cluster formation.

  3. Ice sculpture in the Martian outflow channels

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1982-01-01

    Viking Orbiter and terrestrial satellite images are examined at similar resolution to compare features of the Martian outflow channels with features produced by the movement of ice on earth, and many resemblances are found. These include the anastomoses, sinuosities, and U-shaped cross profiles of valleys; hanging valleys; linear scour marks on valley walls; grooves and ridges on valley floors; and the streamlining of bedrock highs. Attention is given to the question whether ice could have moved in the Martian environment. It is envisaged that springs or small catastrophic outbursts discharged fluids from structural outlets or chaotic terrains. These fluids built icings that may have grown into substantial masses and eventually flowed like glaciers down preexisting valleys. An alternative is that the fluids formed rivers or floods that in turn formed ice jams and consolidated into icy masses in places where obstacles blocked their flow.

  4. FIRE simulations: galactic outflows and their consequences

    NASA Astrophysics Data System (ADS)

    Keres, Dusan; FIRE team

    2016-06-01

    We study gaseous outflows and their consequences in high-resolution galaxy formation simulations with explicit stellar feedback from the Feedback in Realistic Environments project. Collective, galaxy scale, effect of stellar feedback results in episodic ejections of large amount of gas and heavy elements into the circum-galactic medium. Gas ejection episodes follow strong bursts of star formation. Properties of galactic star formation and ejection episodes depend on galaxy mass and redshift and, together with gas infall and recycling, shape the evolution of the circum-galactic medium and galaxies. As a consequence, our simulated galaxies have masses, star formation histories and heavy element content in good agreement with the observed population of galaxies.

  5. Simulation of Breach Outflow for Earthfill Dam

    NASA Astrophysics Data System (ADS)

    Razad, Azwin Zailti Abdul; Sabri Muda, Rahsidi; Mohd Sidek, Lariyah; Azia, Intan Shafilah Abdul; Hanum Mansor, Faezah; Yalit, Ruzaimei

    2013-06-01

    Dams have been built for many reasons such as irrigation, hydropower, flood mitigation, and water supply to support development for the benefit of human. However, the huge amount of water stored behind the dam can seriously pose adverse impacts to the downstream community should it be released due to unwanted dam break event. To minimise the potential loss of lives and property damages, a workable Emergency Response Plan is required to be developed. As part of a responsible dam owner and operator, TNB initiated a study on dam breach modelling for Cameron Highlands Hydroelectric Scheme to simulate the potential dam breach for Jor Dam. Prediction of dam breach parameters using the empirical equations of Froehlich and Macdonal-Langridge-Monopolis formed the basis of the modelling, coupled with MIKE 11 software to obtain the breach outflow due to Probable Maximum Flood (PMF). This paper will therefore discuss the model setup, simulation procedure and comparison of the prediction with existing equations.

  6. Optically thick outflows in ultraluminous supersoft sources

    NASA Astrophysics Data System (ADS)

    Urquhart, R.; Soria, R.

    2016-02-01

    Ultraluminous supersoft sources (ULSs) are defined by a thermal spectrum with colour temperatures ˜0.1 keV, bolometric luminosities ˜ a few 1039 erg s-1, and almost no emission above 1 keV. It has never been clear how they fit into the general scheme of accreting compact objects. To address this problem, we studied a sample of seven ULSs with extensive Chandra and XMM-Newton coverage. We find an anticorrelation between fitted temperatures and radii of the thermal emitter, and no correlation between bolometric luminosity and radius or temperature. We compare the physical parameters of ULSs with those of classical supersoft sources, thought to be surface-nuclear-burning white dwarfs, and of ultraluminous X-ray sources (ULXs), thought to be super-Eddington stellar-mass black holes. We argue that ULSs are the sub-class of ULXs seen through the densest wind, perhaps an extension of the soft-ultraluminous regime. We suggest that in ULSs, the massive disc outflow becomes effectively optically thick and forms a large photosphere, shrouding the inner regions from our view. Our model predicts that when the photosphere expands to ≳ 105 km and the temperature decreases below ≈50 eV, ULSs become brighter in the far-UV but undetectable in X-rays. Conversely, we find that harder emission components begin to appear in ULSs when the fitted size of the thermal emitter is smallest (interpreted as a shrinking of the photosphere). The observed short-term variability and absorption edges are also consistent with clumpy outflows. We suggest that the transition between ULXs (with a harder tail) and ULSs (with only a soft thermal component) occurs at blackbody temperatures of ≈150 eV.

  7. Myocardialization of the cardiac outflow tract

    NASA Technical Reports Server (NTRS)

    van den Hoff, M. J.; Moorman, A. F.; Ruijter, J. M.; Lamers, W. H.; Bennington, R. W.; Markwald, R. R.; Wessels, A.

    1999-01-01

    During development, the single-circuited cardiac tube transforms into a double-circuited four-chambered heart by a complex process of remodeling, differential growth, and septation. In this process the endocardial cushion tissues of the atrioventricular junction and outflow tract (OFT) play a crucial role as they contribute to the mesenchymal components of the developing septa and valves in the developing heart. After fusion, the endocardial ridges in the proximal portion of the OFT initially form a mesenchymal outlet septum. In the adult heart, however, this outlet septum is basically a muscular structure. Hence, the mesenchyme of the proximal outlet septum has to be replaced by cardiomyocytes. We have dubbed this process "myocardialization." Our immunohistochemical analysis of staged chicken hearts demonstrates that myocardialization takes place by ingrowth of existing myocardium into the mesenchymal outlet septum. Compared to other events in cardiac septation, it is a relatively late process, being initialized around stage H/H28 and being basically completed around stage H/H38. To unravel the molecular mechanisms that are responsible for the induction and regulation of myocardialization, an in vitro culture system in which myocardialization could be mimicked and manipulated was developed. Using this in vitro myocardialization assay it was observed that under the standard culture conditions (i) whole OFT explants from stage H/H20 and younger did not spontaneously myocardialize the collagen matrix, (ii) explants from stage H/H21 and older spontaneously formed extensive myocardial networks, (iii) the myocardium of the OFT could be induced to myocardialize and was therefore "myocardialization-competent" at all stages tested (H/H16-30), (iv) myocardialization was induced by factors produced by, most likely, the nonmyocardial component of the outflow tract, (v) at none of the embryonic stages analyzed was ventricular myocardium myocardialization-competent, and finally

  8. Searching for molecular outflows in hyperluminous infrared galaxies

    NASA Astrophysics Data System (ADS)

    Calderón, D.; Bauer, F. E.; Veilleux, S.; Graciá-Carpio, J.; Sturm, E.; Lira, P.; Schulze, S.; Kim, S.

    2016-08-01

    We present constraints on the molecular outflows in a sample of five hyperluminous infrared galaxies using Herschel observations of the OH doublet at 119 μm. We have detected the OH doublet in three cases: one purely in emission and two purely in absorption. The observed emission profile has a significant blueshifted wing suggesting the possibility of tracing an outflow. Out of the two absorption profiles, one seems to be consistent with the systemic velocity while the other clearly indicates the presence of a molecular outflow whose maximum velocity is about ˜1500 km s-1. Our analysis shows that this system is in general agreement with previous results on ultraluminous infrared galaxies and QSOs, whose outflow velocities do not seem to correlate with stellar masses or starburst luminosities (star formation rates). Instead, the galaxy outflow likely arises from an embedded active galactic nuclei.

  9. Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus

    PubMed Central

    Rith, Sareth; Chin, Savuth; Sar, Borann; Y, Phalla; Horm, Srey Viseth; Ly, Sovann; Buchy, Philippe; Dussart, Philippe; Horwood, Paul F.

    2015-01-01

    Background Despite annual co-circulation of different subtypes of seasonal influenza, co-infections between different viruses are rarely detected. These co-infections can result in the emergence of reassortant progeny. Study design We document the detection of an influenza co-infection, between influenza A/H3N2 with A/H1N1pdm09 viruses, which occurred in a 3 year old male in Cambodia during April 2014. Both viruses were detected in the patient at relatively high viral loads (as determined by real-time RT-PCR CT values), which is unusual for influenza co-infections. As reassortment can occur between co-infected influenza A strains we isolated plaque purified clonal viral populations from the clinical material of the patient infected with A/H3N2 and A/H1N1pdm09. Results Complete genome sequences were completed for 7 clonal viruses to determine if any reassorted viruses were generated during the influenza virus co-infection. Although most of the viral sequences were consistent with wild-type A/H3N2 or A/H1N1pdm09, one reassortant A/H3N2 virus was isolated which contained an A/H1N1pdm09 NS1 gene fragment. The reassortant virus was viable and able to infect cells, as judged by successful passage in MDCK cells, achieving a TCID50 of 104/ml at passage number two. There is no evidence that the reassortant virus was transmitted further. The co-infection occurred during a period when co-circulation of A/H3N2 and A/H1N1pdm09 was detected in Cambodia. Conclusions It is unclear how often influenza co-infections occur, but laboratories should consider influenza co-infections during routine surveillance activities. PMID:26590689

  10. Evolution of active region outflows throughout an active region lifetime

    NASA Astrophysics Data System (ADS)

    Zangrilli, L.; Poletto, G.

    2016-10-01

    Context. We have shown previously that SOHO/UVCS data allow us to detect active region (AR) outflows at coronal altitudes higher than those reached by other instrumentation. These outflows are thought to be a component of the slow solar wind. Aims: Our purpose is to study the evolution of the outflows in the intermediate corona from AR 8100, from the time the AR first forms until it dissolves, after several transits at the solar limb. Methods: Data acquired by SOHO/UVCS at the time of the AR limb transits, at medium latitudes and at altitudes ranging from 1.5 to 2.3 R⊙, were used to infer the physical properties of the outflows through the AR evolution. To this end, we applied the Doppler dimming technique to UVCS spectra. These spectra include the H i Lyα line and the O vi doublet lines at 1031.9 and 1037.6 Å. Results: Plasma speeds and electron densities of the outflows were inferred over several rotations of the Sun. AR outflows are present in the newly born AR and persist throughout the entire AR life. Moreover, we found two types of outflows at different latitudes, both possibly originating in the same negative polarity area of the AR. We also analyzed the behavior of the Si xii 520 Å line along the UVCS slit in an attempt to reveal changes in the Si abundance when different regions are traversed. Although we found some evidence for a Si enrichment in the AR outflows, alternative interpretations are also plausible. Conclusions: Our results demonstrate that outflows from ARs are detectable in the intermediate corona throughout the whole AR lifetime. This confirms that outflows contribute to the slow wind.

  11. Development and Morphology of the Ventricular Outflow Tracts.

    PubMed

    Anderson, Robert H; Mori, Shumpei; Spicer, Diane E; Brown, Nigel A; Mohun, Timothy J

    2016-09-01

    It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts. Congenital lesions afflicting the arterial roots, however, are not currently considered to be conotruncal malformations. This suggests a lack of logic in the description of cardiac development and its use as a means of categorizing congenital malformations. It is our belief that the developing outflow tract, like the postnatal outflow tracts, can readily be described in tripartite fashion, with its distal, intermediate, and proximal components forming the primordiums of the postnatal parts. In this review, we present evidence obtained from developing mice and human hearts to substantiate this notion. We show that the outflow tract, initially with a common lumen, is divided into its aortic and pulmonary components by a combination of an aortopulmonary septum derived from the dorsal wall of the aortic sac and outflow tract cushions that spiral through its intermediate and proximal components. These embryonic septal structures, however, subsequently lose their septal functions as the outflow tracts develop their own discrete walls. We then compare the developmental findings with the anatomic arrangements seen postnatally in the normal human heart. We show how correlations with the embryologic findings permit logical analysis of the congenital lesions involving the outflow tracts. PMID:27587491

  12. Development and Morphology of the Ventricular Outflow Tracts

    PubMed Central

    Mori, Shumpei; Spicer, Diane E.; Brown, Nigel A.; Mohun, Timothy J.

    2016-01-01

    It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts. Congenital lesions afflicting the arterial roots, however, are not currently considered to be conotruncal malformations. This suggests a lack of logic in the description of cardiac development and its use as a means of categorizing congenital malformations. It is our belief that the developing outflow tract, like the postnatal outflow tracts, can readily be described in tripartite fashion, with its distal, intermediate, and proximal components forming the primordiums of the postnatal parts. In this review, we present evidence obtained from developing mice and human hearts to substantiate this notion. We show that the outflow tract, initially with a common lumen, is divided into its aortic and pulmonary components by a combination of an aortopulmonary septum derived from the dorsal wall of the aortic sac and outflow tract cushions that spiral through its intermediate and proximal components. These embryonic septal structures, however, subsequently lose their septal functions as the outflow tracts develop their own discrete walls. We then compare the developmental findings with the anatomic arrangements seen postnatally in the normal human heart. We show how correlations with the embryologic findings permit logical analysis of the congenital lesions involving the outflow tracts. PMID:27587491

  13. A distance-limited sample of massive molecular outflows

    NASA Astrophysics Data System (ADS)

    Maud, L. T.; Moore, T. J. T.; Lumsden, S. L.; Mottram, J. C.; Urquhart, J. S.; Hoare, M. G.

    2015-10-01

    We have observed 99 mid-infrared-bright, massive young stellar objects and compact H II regions drawn from the Red MSX source survey in the J = 3-2 transition of 12CO and 13CO, using the James Clerk Maxwell Telescope. 89 targets are within 6 kpc of the Sun, covering a representative range of luminosities and core masses. These constitute a relatively unbiased sample of bipolar molecular outflows associated with massive star formation. Of these, 59, 17 and 13 sources (66, 19 and 15 per cent) are found to have outflows, show some evidence of outflow, and have no evidence of outflow, respectively. The time-dependent parameters of the high-velocity molecular flows are calculated using a spatially variable dynamic time-scale. The canonical correlations between the outflow parameters and source luminosity are recovered and shown to scale with those of low-mass sources. For coeval star formation, we find the scaling is consistent with all the protostars in an embedded cluster providing the outflow force, with massive stars up to ˜30 M⊙ generating outflows. Taken at face value, the results support the model of a scaled-up version of the accretion-related outflow-generation mechanism associated with discs and jets in low-mass objects with time-averaged accretion rates of ˜10-3 M⊙ yr-1 on to the cores. However, we also suggest an alternative model, in which the molecular outflow dynamics are dominated by the entrained mass and are unrelated to the details of the acceleration mechanism. We find no evidence that outflows contribute significantly to the turbulent kinetic energy of the surrounding dense cores.

  14. Functional Conservation and Divergence of Four Ginger AP1/AGL9 MADS–Box Genes Revealed by Analysis of Their Expression and Protein–Protein Interaction, and Ectopic Expression of AhFUL Gene in Arabidopsis

    PubMed Central

    Song, Juanjuan; Sun, Wei; Xia, Kuaifei; Liao, Jingping; Zhang, Mingyong

    2014-01-01

    Alpinia genus are known generally as ginger–lilies for showy flowers in the ginger family, Zingiberaceae, and their floral morphology diverges from typical monocotyledon flowers. However, little is known about the functions of ginger MADS–box genes in floral identity. In this study, four AP1/AGL9 MADS–box genes were cloned from Alpinia hainanensis, and protein–protein interactions (PPIs) and roles of the four genes in floral homeotic conversion and in floral evolution are surveyed for the first time. AhFUL is clustered to the AP1lineage, AhSEP4 and AhSEP3b to the SEP lineage, and AhAGL6–like to the AGL6 lineage. The four genes showed conserved and divergent expression patterns, and their encoded proteins were localized in the nucleus. Seven combinations of PPI (AhFUL–AhSEP4, AhFUL–AhAGL6–like, AhFUL–AhSEP3b, AhSEP4–AhAGL6–like, AhSEP4–AhSEP3b, AhAGL6–like–AhSEP3b, and AhSEP3b–AhSEP3b) were detected, and the PPI patterns in the AP1/AGL9 lineage revealed that five of the 10 possible combinations are conserved and three are variable, while conclusions cannot yet be made regarding the other two. Ectopic expression of AhFUL in Arabidopsis thaliana led to early flowering and floral organ homeotic conversion to sepal–like or leaf–like. Therefore, we conclude that the four A. hainanensis AP1/AGL9 genes show functional conservation and divergence in the floral identity from other MADS–box genes. PMID:25461565

  15. The Soluble Guanylate Cyclase Stimulator IWP-953 Increases Conventional Outflow Facility in Mouse Eyes

    PubMed Central

    Ge, Pei; Navarro, Iris D.; Kessler, Marco M.; Bernier, Sylvie G.; Perl, Nicholas R.; Sarno, Renee; Masferrer, Jaime; Hannig, Gerhard; Stamer, W. Daniel

    2016-01-01

    Purpose The nitric oxide (NO)–cyclic guanosine-3′,5′-monophosphate (cGMP) pathway regulates aqueous humor outflow and therefore, intraocular pressure. We investigated the pharmacologic effects of the soluble guanylate cyclase (sGC) stimulator IWP-953 on primary human trabecular meshwork (HTM) cells and conventional outflow facility in mouse eyes. Methods Cyclic GMP levels were determined in vitro in HEK-293 cells and four HTM cell strains (HTM120/HTM123: predominantly myofibroblast-like phenotype, HTM130/HTM141: predominantly endothelial-like phenotype), and in HTM cell culture supernatants. Conventional outflow facility was measured following intracameral injection of IWP-953 or DETA-NO using a computerized pressure-controlled perfusion system in enucleated mouse eyes ex vivo. Results IWP-953 markedly stimulated cGMP production in HEK-293 cells in the presence and absence of DETA-NO (half maximal effective concentrations: 17 nM, 9.5 μM). Similarly, IWP-953 stimulated cGMP production in myofibroblast-like HTM120 and HTM123 cells, an effect that was greatly amplified by the presence of DETA-NO. In contrast, IWP-953 stimulation of cGMP production in endothelial-like HTM130 and HTM141 cells was observed, but was markedly less prominent than in HTM120 and HTM123 cells. Notably, cGMP was found in all HTM culture supernatants, following IWP-953/DETA-NO stimulation. In paired enucleated mouse eyes, IWP-953 at 10, 30, 60, and 100 μM concentration-dependently increased outflow facility. This effect (89.5%) was maximal at 100 μM (P = 0.002) and in magnitude comparable to DETA-NO at 100 μM (97.5% increase, P = 0.030). Conclusions These data indicate that IWP-953, via modulation of the sGC–cGMP pathway, increases aqueous outflow facility in mouse eyes, suggesting therapeutic potential for sGC stimulators as novel ocular hypotensive drugs. PMID:26998718

  16. Vascular Endothelial Growth Factor-A Increases the Aqueous Humor Outflow Facility

    PubMed Central

    Fujimoto, Tomokazu; Inoue, Toshihiro; Maki, Kei; Inoue-Mochita, Miyuki; Tanihara, Hidenobu

    2016-01-01

    Purpose Anti-vascular endothelial growth factor (VEGF) antibody therapy is an effective treatment for ocular angiogenesis. Although the intraocular pressure of some patients increases after anti-VEGF therapy, the effects of VEGF-A on the aqueous humor outflow pathway remain unknown. This study investigated the effects of VEGF-A on the aqueous humor outflow pathway. Methods We used human recombinant VEGF121 and VEGF165. Trabecular meshwork (TM) and Schlemm’s canal endothelial (SCE) cells were isolated from the eyes of cynomolgus monkeys. Expression of mRNA coding four VEGF receptors, VEGFR1 (FLT1), VEGFR2 (KDR), neuropilin-1, and neuropilin-2, was examined by RT-PCR. To evaluate the permeability of cell monolayers, we measured transendothelial electrical resistance (TEER). The outflow facility was measured in perfused porcine anterior segment organ cultures treated with 30 ng/mL VEGF121 for 48 h. Results Four VEGF-A-related receptor mRNAs were expressed in TM and SCE cells. The TEER of TM cells was not significantly affected by VEGF121 or VEGF165 treatment. In contrast, the TEER of SCE cells was significantly lower 48 h after treatment with 30 ng/mL VEGF121 to 69.4 ± 12.2% of baseline (n = 10), which was a significant difference compared with the control (P = 0.0001). VEGF165 (30 ng/mL) decreased the TEER of SCE cells at 48 h after treatment to 72.3 ± 14.1% compared with the baseline (n = 10), which was not a significant difference compared with the control (P = 0.0935). Ki8751, a selective VEGFR2 inhibitor, completely suppressed the effect of VEGF121 on SCE cell permeability, although ZM306416, a selective VEGFR1 inhibitor, did not affect the VEGF121-induced decrease in TEER. Perfusion with 30 ng/mL of VEGF121 for 48 h significantly increased the outflow facility compared with the control (47.8 ± 28.5%, n = 5, P = 0.013). Conclusions These results suggest that VEGF-A may regulate the conventional aqueous outflow of SCE cells through VEGFR2. PMID:27584577

  17. Mechanosensory S-neurons rather than AH-neurons appear to generate a rhythmic motor pattern in guinea-pig distal colon

    PubMed Central

    Spencer, Nick J; Smith, Terence K

    2004-01-01

    Simultaneous intracellular recordings were made from myenteric neurons and circular muscle (CM) cells in isolated, stretched segments of guinea-pig distal colon. We have shown previously that maintained stretch generates a repetitive and coordinated discharge of ascending excitatory and descending inhibitory neuronal reflex pathways in the distal colon. In the presence of nifedipine (1–2 μm) to paralyse the muscle, simultaneous recordings were made from 25 pairs of AH (after-hyperpolarization)-neurons and CM cells separated by 100–500 μm. In all 25 AH-neurons, proximal process potentials (PPPs) were never recorded, even though at the same time, all recordings from neighbouring CM cells showed an ongoing discharge of inhibitory junction potentials (IJPs) anally, or excitatory junction potentials (EJPs) orally. In fact, 24 of 25 AH-neurons were totally silent, while in one AH-cell, some spontaneous fast excitatory postsynaptic potentials (FEPSPs) were recorded. All 10 electrically silent AH-cells that were injected with neurobiotin were found to be multipolar Dogiel type II neurons. In contrast, when recordings were made from myenteric S-neurons, two distinct electrical patterns of electrical activity were recorded. Recordings from 25 of 48 S-neurons showed spontaneous FEPSPs, the majority of which (22 of 25) showed periods when discrete clusters of FEPSPs (mean duration 88 ms) could be temporally correlated with the onset of EJPs or anal IJPs in the CM. Nine S-neurons were electrically quiescent. The second distinct electrical pattern in 14 S-neurons consisted of bursts, or prolonged trains of action potentials, which could be reduced to proximal process potentials (PPPs) in six of these 14 neurons during membrane hyperpolarization. Unlike FEPSPs, PPPs were resistant to a low Ca2+ –high Mg2+ solution and did not change in amplitude during hyperpolarizing pulses. Mechanosensory S-neurons were found to be uniaxonal or pseudounipolar filamentous neurons, with

  18. Simulation of California's Major Reservoirs Outflow Using Data Mining Technique

    NASA Astrophysics Data System (ADS)

    Yang, T.; Gao, X.; Sorooshian, S.

    2014-12-01

    The reservoir's outflow is controlled by reservoir operators, which is different from the upstream inflow. The outflow is more important than the reservoir's inflow for the downstream water users. In order to simulate the complicated reservoir operation and extract the outflow decision making patterns for California's 12 major reservoirs, we build a data-driven, computer-based ("artificial intelligent") reservoir decision making tool, using decision regression and classification tree approach. This is a well-developed statistical and graphical modeling methodology in the field of data mining. A shuffled cross validation approach is also employed to extract the outflow decision making patterns and rules based on the selected decision variables (inflow amount, precipitation, timing, water type year etc.). To show the accuracy of the model, a verification study is carried out comparing the model-generated outflow decisions ("artificial intelligent" decisions) with that made by reservoir operators (human decisions). The simulation results show that the machine-generated outflow decisions are very similar to the real reservoir operators' decisions. This conclusion is based on statistical evaluations using the Nash-Sutcliffe test. The proposed model is able to detect the most influential variables and their weights when the reservoir operators make an outflow decision. While the proposed approach was firstly applied and tested on California's 12 major reservoirs, the method is universally adaptable to other reservoir systems.

  19. PROTOSTELLAR OUTFLOWS AND RADIATIVE FEEDBACK FROM MASSIVE STARS

    SciTech Connect

    Kuiper, Rolf; Yorke, Harold W.; Turner, Neal J. E-mail: Harold.W.Yorke@jpl.nasa.gov

    2015-02-20

    We carry out radiation hydrodynamical simulations of the formation of massive stars in the super-Eddington regime including both their radiative feedback and protostellar outflows. The calculations start from a prestellar core of dusty gas and continue until the star stops growing. The accretion ends when the remnants of the core are ejected, mostly by the force of the direct stellar radiation in the polar direction and elsewhere by the reradiated thermal infrared radiation. How long the accretion persists depends on whether the protostellar outflows are present. We set the mass outflow rate to 1% of the stellar sink particle's accretion rate. The outflows open a bipolar cavity extending to the core's outer edge, through which the thermal radiation readily escapes. The radiative flux is funneled into the polar directions while the core's collapse proceeds near the equator. The outflow thus extends the ''flashlight effect'', or anisotropic radiation field, found in previous studies from the few hundred AU scale of the circumstellar disk up to the 0.1 parsec scale of the core. The core's flashlight effect allows core gas to accrete on the disk for longer, in the same way that the disk's flashlight effect allows disk gas to accrete on the star for longer. Thus although the protostellar outflows remove material near the core's poles, causing slower stellar growth over the first few free-fall times, they also enable accretion to go on longer in our calculations. The outflows ultimately lead to stars of somewhat higher mass.

  20. PROTOSTELLAR JETS ENCLOSED BY LOW-VELOCITY OUTFLOWS

    SciTech Connect

    Machida, Masahiro N.

    2014-11-20

    A protostellar jet and outflow are calculated for ∼270 yr following the protostar formation using a three-dimensional magnetohydrodynamics simulation, in which both the protostar and its parent cloud are spatially resolved. A high-velocity (∼100 km s{sup –1}) jet with good collimation is driven near the disk's inner edge, while a low-velocity (≲ 10 km s{sup –1}) outflow with a wide opening angle appears in the outer-disk region. The high-velocity jet propagates into the low-velocity outflow, forming a nested velocity structure in which a narrow high-velocity flow is enclosed by a wide low-velocity flow. The low-velocity outflow is in a nearly steady state, while the high-velocity jet appears intermittently. The time-variability of the jet is related to the episodic accretion from the disk onto the protostar, which is caused by gravitational instability and magnetic effects such as magnetic braking and magnetorotational instability. Although the high-velocity jet has a large kinetic energy, the mass and momentum of the jet are much smaller than those of the low-velocity outflow. A large fraction of the infalling gas is ejected by the low-velocity outflow. Thus, the low-velocity outflow actually has a more significant effect than the high-velocity jet in the very early phase of the star formation.

  1. Progressive antigenic drift and phylogeny of human influenza A(H3N2) virus over five consecutive seasons (2009-2013) in Hangzhou, China.

    PubMed

    Shao, Tie-Juan; Li, Jun; Yu, Xin-Fen; Kou, Yu; Zhou, Yin-Yan; Qian, Xin

    2014-12-01

    Vaccine efficacy (VE) can be affected by progressive antigenic drift or any new reassortment of influenza viruses. To effectively track the evolution of human influenza A(H3N2) virus circulating in Hangzhou, China, a total of 65 clinical specimens were selected randomly from outpatients infected by A(H3N2) viruses during the study period from November 2009 to December 2013. The results of reduced VE and antigenic drift of the correspondent epitopes (C-D-E to A-B) suggest that the current vaccine provides suboptimal protection against the A(H3N2) strains circulating recently. Phylogenetic analysis of the entire HA and NA sequences demonstrated that these two genes underwent independent evolutionary pathways during recent seasons. The H3-based phylogenetic tree showed that a special strain A/Hangzhou/A289/2012 fell in a cluster among viruses with reduced VE predominantly circulating in 2013. Our findings underscore a possible early warning for the circulation of A(H3N2) variants with antigenic drift during the previous seasons.

  2. Outflow and hot dust emission in broad absorption line quasars

    SciTech Connect

    Zhang, Shaohua; Zhou, Hongyan; Wang, Huiyuan; Wang, Tinggui; Xing, Feijun; Jiang, Peng; Zhang, Kai E-mail: whywang@mail.ustc.edu.cn

    2014-05-01

    We have investigated a sample of 2099 broad absorption line (BAL) quasars with z = 1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in the literature and is refined by our new algorithm. Correlations of outflow velocity and strength with a hot dust indicator (β{sub NIR}) and other quasar physical parameters—such as an Eddington ratio, luminosity, and a UV continuum slope—are explored in order to figure out which parameters drive outflows. Here β{sub NIR} is the near-infrared continuum slope, which is a good indicator of the amount of hot dust emission relative to the accretion disk emission. We confirm previous findings that outflow properties moderately or weakly depend on the Eddington ratio, UV slope, and luminosity. For the first time, we report moderate and significant correlations of outflow strength and velocity with β{sub NIR} in BAL quasars. It is consistent with the behavior of blueshifted broad emission lines in non-BAL quasars. The statistical analysis and composite spectra study both reveal that outflow strength and velocity are more strongly correlated with β{sub NIR} than the Eddington ratio, luminosity, and UV slope. In particular, the composites show that the entire C IV absorption profile shifts blueward and broadens as β{sub NIR} increases, while the Eddington ratio and UV slope only affect the high and low velocity part of outflows, respectively. We discuss several potential processes and suggest that the dusty outflow scenario, i.e., that dust is intrinsic to outflows and may contribute to the outflow acceleration, is most likely.

  3. A Study of PG Quasar-Driven Outflows with COS

    NASA Astrophysics Data System (ADS)

    Hamann, Frederick

    2013-10-01

    Quasar outflows are an important part of the quasar phenomenon, but many questions remain about their energetics, physical properties and the role they might play in providing feedback to host galaxy evolution. We searched our own COS far-UV observations from the QUEST survey and other large COS programs to find a sample of 6 bright PG quasars with broad {FWHM > 400 km/s} high velocity {v > 1000 km/s} absorption lines that clearly form in quasar-driven winds. These quasars can fill an important gap in our understanding between local Seyferts with low-speed winds and high-redshift quasars with extreme BAL outflows. They are also well-studied at other wavelengths, with some evidence for the quasars driving galaxy-scale blowouts and shutting down star formation. But almost nothing is known about the quasar outflows themselves. We propose a detailed study of these 6 outflow quasars using new COS FUV observations to 1} expand the existing wavelength coverage across critical lines that are diagnostic of the outflow physical conditions, kinetic energies, and metallicities, and 2} check for line variability as an indicator of the outflow structure and locations. This quasar sample includes unusual cases with many low-abundance {PV 1118,1128 and SIV 1063} and excited-state lines {SIV 1073*, CIII* 1175, CII* 1335} that will provide unprecedented constraints on the outflow properties, plus the first known OVI-only mini-BAL outflow {no lower ions detected} for which we will cover NeVIII 770,780 to probe the highest ionization gas. The high FUV sensitivity of COS is uniquely able to measure this wide range of outflow lines in low-redshift quasars with no Lya forest contamination.

  4. Contribution of alluvial groundwater to the outflow of mountainous catchments

    NASA Astrophysics Data System (ADS)

    Käser, Daniel; Hunkeler, Daniel

    2016-02-01

    Alluvial aquifers in mountainous regions cover typically a limited area. Their contribution to catchment storage and outflow is rarely isolated; alluvial groundwater discharge under gauging stations is generally assumed negligible; and hydrological models tend to lump alluvial storage with other units. The role of alluvial aquifers remains therefore unclear: can they contribute significantly to outflow when they cover a few percent of catchment area? Should they be considered a dynamic storage unit or merely a transmission zone? We address these issues based on the continuous monitoring of groundwater discharge, river discharge (one year), and aquifer storage (6 months) in the 6 km2 alluvial system of a 194 km2 catchment. River and groundwater outflow were measured jointly through "coupled gauging stations." The contribution of alluvial groundwater to outflow was highest at the outlet of a subcatchment (52 km2), where subsurface discharge amounted to 15% of mean annual outflow, and 85% of outflow during the last week of a drought. In this period, alluvial-aquifer depletion supported 75% of the subcatchment outflow and 35% of catchment outflow—thus 3% of the entire catchment supported a third of the outflow. Storage fluctuations occurred predominantly in the aquifer's upstream part, where heads varied over 6 m. Not only does this section act as a significant water source, but storage recovers also rapidly at the onset of precipitation. Storage dynamics were best conceptualized along the valley axis, rather than across the more conventional riparian-channel transect. Overall the contribution of alluvial aquifers to catchment outflow deserves more attention.

  5. Assessing Antigenic Drift of Seasonal Influenza A(H3N2) and A(H1N1)pdm09 Viruses.

    PubMed

    Tewawong, Nipaporn; Prachayangprecha, Slinporn; Vichiwattana, Preeyaporn; Korkong, Sumeth; Klinfueng, Sirapa; Vongpunsawad, Sompong; Thongmee, Thanunrat; Theamboonlers, Apiradee; Poovorawan, Yong

    2015-01-01

    Under selective pressure from the host immune system, antigenic epitopes of influenza virus hemagglutinin (HA) have continually evolved to escape antibody recognition, termed antigenic drift. We analyzed the genomes of influenza A(H3N2) and A(H1N1)pdm09 virus strains circulating in Thailand between 2010 and 2014 and assessed how well the yearly vaccine strains recommended for the southern hemisphere matched them. We amplified and sequenced the HA gene of 120 A(H3N2) and 81 A(H1N1)pdm09 influenza virus samples obtained from respiratory specimens and calculated the perfect-match vaccine efficacy using the pepitope model, which quantitated the antigenic drift in the dominant epitope of HA. Phylogenetic analysis of the A(H3N2) HA1 genes classified most strains into genetic clades 1, 3A, 3B, and 3C. The A(H3N2) strains from the 2013 and 2014 seasons showed very low to moderate vaccine efficacy and demonstrated antigenic drift from epitopes C and A to epitope B. Meanwhile, most A(H1N1)pdm09 strains from the 2012-2014 seasons belonged to genetic clades 6A, 6B, and 6C and displayed the dominant epitope mutations at epitopes B and E. Finally, the vaccine efficacy for A(H1N1)pdm09 (79.6-93.4%) was generally higher than that of A(H3N2). These findings further confirmed the accelerating antigenic drift of the circulating influenza A(H3N2) in recent years.

  6. Ion Outflow from Venus and Mars and the Processes Involved

    NASA Astrophysics Data System (ADS)

    Stenberg Wieser, G.; Holmstrom, M.; Futaana, Y.

    2015-12-01

    We review the ion outflow from Venus and Mars. We present the current best estimates of the escaping fluxes and describe the acceleration processes that have been identified. We discuss which solar wind parameters govern the response of the ionosphere as well as the role of the crustal magnetic fields on Mars. Although the characteristics of the two planets are very different, we find both similarities and differences when investigating the ion escape morphology and dynamics. Finally, we compare Venus and Mars with Earth and discuss the effect of a global intrinsic magnetic field on ion outflow and the potential importance of outflowing cold ions.

  7. Accretion driven outflows across the black hole mass scale

    NASA Astrophysics Data System (ADS)

    King, Ashley L.

    2016-04-01

    Pumping highly relativistic particles and radiation into their environment, accreting black holes co-evolve with their surroundings through their powerful outflows. These outflows are divided into highly collimated, relativistic jets and wide-angle winds, and are primarily associated with a particular accretion states. Understanding just how these outflows couple to the accretion flow will enable us to assess the amount of energy and feedback that is injected into the vicinity of a black hole. During this talk, I will discuss our studies of both stellar-mass and supermassive black hole outlfows, and how the similarities of these flows across the mass scale may point to common driving mechanisms.

  8. Numerical Modeling of η Carinae Bipolar Outflows

    NASA Astrophysics Data System (ADS)

    González, R. F.; de Gouveia Dal Pino, E. M.; Raga, A. C.; Velázquez, P. F.

    2004-12-01

    In this paper, we present two-dimensional gasdynamic simulations of the formation and evolution of the η Car bipolar outflows. Adopting the interacting nonspherical winds model, we have carried out high-resolution numerical simulations, which include explicitly computed time-dependent radiative cooling, for different possible scenarios of the colliding winds. In our simulations, we consider different degrees of nonspherical symmetry for the preoutburst wind and the great eruption of the 1840s produced by the η Car wind. Different models show important differences in the shape and kinematical properties of the Homunculus structure. In particular, we search for the appropriate combination of wind parameters (which control the degree of nonspherical symmetry) to obtain the numerical results that best match both the observed morphology and the expansion velocity of the η Car bipolar shell. In addition, our numerical simulations show the formation of a bipolar nebula embedded within the Homunculus (the little Homunculus) that developed from a secondary eruptive event suffered by the star in the 1890s, and also the development of tenuous, high-velocity ejections in the equatorial region that resulted from the impact of the eruptive wind of the 1840s with the preoutburst wind; these ejections could explain some of the high-speed features observed in the equatorial ejecta. The models were, however, unable to produce the equatorial ejections associated with the second eruptive event.

  9. HOT ELECTROMAGNETIC OUTFLOWS. II. JET BREAKOUT

    SciTech Connect

    Russo, Matthew; Thompson, Christopher

    2013-08-20

    We consider the interaction between radiation, matter, and a magnetic field in a compact, relativistic jet. The entrained matter accelerates outward as the jet breaks out of a star or other confining medium. In some circumstances, such as gamma-ray bursts (GRBs), the magnetization of the jet is greatly reduced by an advected radiation field while the jet is optically thick to scattering. Where magnetic flux surfaces diverge rapidly, a strong outward Lorentz force develops and radiation and matter begin to decouple. The increase in magnetization is coupled to a rapid growth in Lorentz factor. We take two approaches to this problem. The first examines the flow outside the fast magnetosonic critical surface, and calculates the flow speed and the angular distribution of the radiation field over a range of scattering depths. The second considers the flow structure on both sides of the critical surface in the optically thin regime, using a relaxation method. In both approaches, we find how the terminal Lorentz factor and radial profile of the outflow depend on the radiation intensity and optical depth at breakout. The effect of bulk Compton scattering on the radiation spectrum is calculated by a Monte Carlo method, while neglecting the effects of internal dissipation. The peak of the scattered spectrum sits near the seed peak if radiation pressure dominates the acceleration, but is pushed to a higher frequency if the Lorentz force dominates. The unscattered seed radiation can form a distinct, low-frequency component of the spectrum, especially if the magnetic Poynting flux dominates.

  10. A 65 Ah rechargeable lithium molybdenum disulfide battery

    NASA Technical Reports Server (NTRS)

    Brandt, K.

    1986-01-01

    A rechargeable lithium molybdenum disulfide battery which has a number of superior performance characteristics which includes a high energy density, a high power density, and a long charge retention time was developed. The first cell sizes developed included a C size cell and an AA size cell. Over the last two years, a project to demonstrate the feasibility of the scale up to this technology to a BC size cell with 65 Ah capacity was undertaken. The objective was to develop, build, and test a .6 kWh storage battery consisting of 6 BC cells in series.

  11. Calorimetry of 25 Ah lithium/thionyl chloride cells

    NASA Technical Reports Server (NTRS)

    Johnson, C. J.; Dawson, S.

    1991-01-01

    Heat flow measurements of 25-Ah lithium thionyl chloride cells provided a method to calculate an effective thermal potential, E(TP) of 3.907 V. The calculation is useful to determine specific heat generation of this cell chemistry and design. The E(TP) value includes heat generation by electrochemical cell reactions, competitive chemical reactions, and resistance heating at the tabs, connectors, and leads. Heat flow was measured while applying electrical loads to the cell in an isothermal calorimeter set at 0, 20, and 60 C.

  12. Hydrothermal outflow plume of Valles caldera, New Mexico, and a comparison with other outflow plumes

    SciTech Connect

    Goff, F.; Shevenell, L.; Gardner, J.N.; Vuataz, F.; Grigsby, C.O.

    1988-06-10

    Stratigraphic, temperature gradient, hydrogeochemical, and hydrologic data have been integrated with geologic data from previous studies to show the structural configuration of the Valles caldera hydrothermal outflow plume. Hydrologic data suggest that 25--50% of the discharge of the Valles outflow is confined to the Jemez fault zone, which predates caldera formation. Thermal gradient data from bores penetrating the plume show that shallow gradients are highest in the vicinity of the Jemez fault zone (up to 190 /sup 0/C/km). Shallow heat flow above the hydrothermal plume is as high as 500 mW m/sup -2/ near core hole VC-1 (Jemez fault zone) to 200 mW m/sup -2/ at Fenton Hill (Jemez Plateau). Chemical and isotopic data indicate that two source reservoirs within the caldera (Redondo Creek and Sulphur Springs reservoirs) are parents to mixed fluids flowing in the hydrothermal plume. However, isotopic data, borehole data, basic geology, and inverse relations between temperature and chloride content at major hot springs indicate that no single reservoir fluid and no single diluting fluid are involved in mixing. The Valles caldera hydrothermal plume is structurally dominated by lateral flow through a belt of vertical conduits (Jemez fault zone) that strike away from the source reservoir. Stratigraphically confined flow is present but dispersed over a wide area in relatively impermeable rocks. The Valles configuration is contrasted with the configuration of the hydrothermal plume at Roosevelt Hot Springs, which is dominated by lateral flow through a near-surface, widespread, permeable aquifer. Data from 12 other representative geothermal systems show that outflow plumes occur in a variety of magmatic and tectonic settings, have varying reservoir compositions, and have different flow characteristics.

  13. Indirect measurement of Delta outflow using ultrasonic velocity meters and comparison with mass-balance calculated outflow

    USGS Publications Warehouse

    Oltmann, Richard N.

    1998-01-01

    A measurement of the quantity of water flowing from the Sacramento-San Joaquin Delta into Suisun Bay (Delta outflow) has been desired by those studying and managing the San Francisco Bay/Delta estuary since the 1920s.  Historically, Delta outflow has been estimated using a mass-balance calculation that uses measured Delta inflows and exports, and imprecise estimates of consumptive use for the approximately 2,000 small agricultural diversions with the Delta.  The DWR has estimated Delta outflow for 1929 to present using the computer program DAYFLOW.

  14. Morphology of Fresh Outflow Channel Deposits on Mars

    NASA Astrophysics Data System (ADS)

    Rice, J. W., Jr.; Parker, T. J.; Russell, A. J.; Knudsen, O.

    2002-03-01

    We interpret the channel surface of Athabasca and Marte Valles to be fresh former ice-rich fluvial (hyperconcentrated) deposits rather than volcanic flows. Simply stated, this is what a fresh outflow channel deposit would look like.

  15. RECONNECTION OUTFLOW GENERATED TURBULENCE IN THE SOLAR WIND

    SciTech Connect

    Vörös, Z.; Sasunov, Y. L.; Zaqarashvili, T. V.; Khodachenko, M.; Semenov, V. S.; Bruno, R.

    2014-12-10

    Petschek-type time-dependent reconnection (TDR) and quasi-stationary reconnection (QSR) models are considered to understand reconnection outflow structures and the generation of local turbulence in the solar wind. Comparing TDR/QSR model predictions of the outflow structures with actual measurements shows that both models can explain the data equally well. It is demonstrated that the outflows can often generate more or less spatially extended turbulent boundary layers. The structure of a unique extended reconnection outflow is investigated in detail. The analysis of spectral scalings and spectral break locations shows that reconnection can change the local field and plasma conditions which may support different local turbulent dissipation mechanisms at their characteristic wavenumbers.

  16. Detection of an Extended Outflow in NGC 4102

    NASA Astrophysics Data System (ADS)

    Trent Braun, Timothy; van Zee, Liese; Richards, Emily E.; McQuinn, Kristen B.; Skillman, Evan D.; Edges

    2015-01-01

    We report the detection of an extended galactic outflow in narrowband H alpha imaging of NGC 4102, a nearby spiral galaxy that hosts a low ionization nuclear emission region (LINER) and a circumnuclear H II region. NGC 4102 is a moderate luminosity galaxy, M_B = -19.3, in the Ursa Major Cluster. The outflow protrudes out to 60' (5 kpc at an adopted distance of 17.4 Mpc) to the northwest of the galactic center and may extend as much as 75' (6.3 kpc.) Follow-up integral field spectroscopic observations reveal split line profiles over the outflow region, indicative of both blue and red shifted emission-line components. Based on [N II] / H alpha and [S II] flux ratios of this region, the line emission appears to be nonthermal. We discuss possible origins of the outflow, including both nuclear and/or starburst activity.

  17. Regulation of Breathing and Autonomic Outflows by Chemoreceptors

    PubMed Central

    Guyenet, Patrice G.

    2016-01-01

    Lung ventilation fluctuates widely with behavior but arterial PCO2 remains stable. Under normal conditions, the chemoreflexes contribute to PaCO2 stability by producing small corrective cardiorespiratory adjustments mediated by lower brainstem circuits. Carotid body (CB) information reaches the respiratory pattern generator (RPG) via nucleus solitarius (NTS) glutamatergic neurons which also target rostral ventrolateral medulla (RVLM) presympathetic neurons thereby raising sympathetic nerve activity (SNA). Chemoreceptors also regulate presympathetic neurons and cardiovagal preganglionic neurons indirectly via inputs from the RPG. Secondary effects of chemoreceptors on the autonomic outflows result from changes in lung stretch afferent and baroreceptor activity. Central respiratory chemosensitivity is caused by direct effects of acid on neurons and indirect effects of CO2 via astrocytes. Central respiratory chemoreceptors are not definitively identified but the retrotrapezoid nucleus (RTN) is a particularly strong candidate. The absence of RTN likely causes severe central apneas in congenital central hypoventilation syndrome. Like other stressors, intense chemosensory stimuli produce arousal and activate circuits that are wake- or attention-promoting. Such pathways (e.g., locus coeruleus, raphe, and orexin system) modulate the chemoreflexes in a state-dependent manner and their activation by strong chemosensory stimuli intensifies these reflexes. In essential hypertension, obstructive sleep apnea and congestive heart failure, chronically elevated CB afferent activity contributes to raising SNA but breathing is unchanged or becomes periodic (severe CHF). Extreme CNS hypoxia produces a stereotyped cardiorespiratory response (gasping, increased SNA). The effects of these various pathologies on brainstem cardiorespiratory networks are discussed, special consideration being given to the interactions between central and peripheral chemoreflexes. PMID:25428853

  18. Identification of TMPRSS2 as a Susceptibility Gene for Severe 2009 Pandemic A(H1N1) Influenza and A(H7N9) Influenza.

    PubMed

    Cheng, Zhongshan; Zhou, Jie; To, Kelvin Kai-Wang; Chu, Hin; Li, Cun; Wang, Dong; Yang, Dong; Zheng, Shufa; Hao, Ke; Bossé, Yohan; Obeidat, Ma'en; Brandsma, Corry-Anke; Song, You-Qiang; Chen, Yu; Zheng, Bo-Jian; Li, Lanjuan; Yuen, Kwok-Yung

    2015-10-15

    The genetic predisposition to severe A(H1N1)2009 (A[H1N1]pdm09) influenza was evaluated in 409 patients, including 162 cases with severe infection and 247 controls with mild infection. We prioritized candidate variants based on the result of a pilot genome-wide association study and a lung expression quantitative trait locus data set. The GG genotype of rs2070788, a higher-expression variant of TMPRSS2, was a risk variant (odds ratio, 2.11; 95% confidence interval, 1.18-3.77; P = .01) to severe A(H1N1)pdm09 influenza. A potentially functional single-nucleotide polymorphism, rs383510, accommodated in a putative regulatory region was identified to tag rs2070788. Luciferase assay results showed the putative regulatory region was a functional element, in which rs383510 regulated TMPRSS2 expression in a genotype-specific manner. Notably, rs2070788 and rs383510 were significantly associated with the susceptibility to A(H7N9) influenza in 102 patients with A(H7N9) influenza and 106 healthy controls. Therefore, we demonstrate that genetic variants with higher TMPRSS2 expression confer higher risk to severe A(H1N1)pdm09 influenza. The same variants also increase susceptibility to human A(H7N9) influenza.

  19. Physical Factors Affecting Outflow Facility Measurements in Mice

    PubMed Central

    Boussommier-Calleja, Alexandra; Li, Guorong; Wilson, Amanda; Ziskind, Tal; Scinteie, Oana Elena; Ashpole, Nicole E.; Sherwood, Joseph M.; Farsiu, Sina; Challa, Pratap; Gonzalez, Pedro; Downs, J. Crawford; Ethier, C. Ross; Stamer, W. Daniel; Overby, Darryl R.

    2015-01-01

    Purpose Mice are commonly used to study conventional outflow physiology. This study examined how physical factors (hydration, temperature, and anterior chamber [AC] deepening) influence ocular perfusion measurements in mice. Methods Outflow facility (C) and pressure-independent outflow (Fu) were assessed by multilevel constant pressure perfusion of enucleated eyes from C57BL/6 mice. To examine the effect of hydration, seven eyes were perfused at room temperature, either immersed to the limbus in saline and covered with wet tissue paper or exposed to room air. Temperature effects were examined in 12 eyes immersed in saline at 20°C or 35°C. Anterior chamber deepening was examined in 10 eyes with the cannula tip placed in the anterior versus posterior chamber (PC). Posterior bowing of the iris (AC deepening) was visualized by three-dimensional histology in perfusion-fixed C57BL/6 eyes and by spectral-domain optical coherence tomography in living CD1 mice. Results Exposure to room air did not significantly affect C, but led to a nonzero Fu that was significantly reduced upon immersion in saline. Increasing temperature from 20°C to 35°C increased C by 2.5-fold, more than could be explained by viscosity changes alone (1.4-fold). Perfusion via the AC, but not the PC, led to posterior iris bowing and increased outflow. Conclusions Insufficient hydration contributes to the appearance of pressure-independent outflow in enucleated mouse eyes. Despite the large lens, AC deepening may artifactually increase outflow in mice. Temperature-dependent metabolic processes appear to influence conventional outflow regulation. Physical factors should be carefully controlled in any outflow studies involving mice. PMID:26720486

  20. Analytical Investigation of Mass Outflow Rate in Quasars

    NASA Astrophysics Data System (ADS)

    Das, Santabrata; Chakrabarti, Sandip K.

    Centrifugal force of rapidly infalling matter onto a quasar brakes the flow and forms a centrifugal pressure dominated boundary layer (CENBOL) around the central engine. The thermal and magnetic pressure pushes matter along the axis to form observed radio jets. We present analytical work showing how the inflow influences the nature of CENBOL and dictates the outflow rate from the accretion disks. We show that the outflow rate directly depends on the temperature of CENBOL.

  1. Ultra-fast outflows (aka UFOs) from AGNs and QSOs

    NASA Astrophysics Data System (ADS)

    Cappi, M.; Tombesi, F.; Giustini, M.

    During the last decade, strong observational evidence has been accumulated for the existence of massive, high velocity winds/outflows (aka Ultra Fast Outflows, UFOs) in nearby AGNs and in more distant quasars. Here we briefly review some of the most recent developments in this field and discuss the relevance of UFOs for both understanding the physics of accretion disk winds in AGNs, and for quantifying the global amount of AGN feedback on the surrounding medium.

  2. Toward a Prescription for Feedback from Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib; Bourjaily, M.; Munsell, J.; Brotherton, M. S.; Bhattacharjee, A.; Runnoe, J.; Charlton, J. C.; Eracleous, M.

    2011-01-01

    Models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, distance, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 14000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) estimates of the quasar black hole mass. To this, we are adding photometry from GALEX, 2MASS, and ROSAT in an effort to characterize more fully the quasar SEDs. ROSAT photometry provides estimates of the level of soft X-ray absorption, which helps regulate the velocity of outflows. GALEX photometry samples the extreme ultraviolet range where several high ionization species, that may be present in the outflows, absorb light. 2MASS photometry samples the rest-frame optical, where the effects of absorption and dust reddening are minimal, yield better estimates of the bolometric luminosity (hence, Eddington ratio). In this poster, we will present preliminary measurements of the amount of absorption in the soft X-ray and extreme ultraviolet bands as a function of both outflow properties and quasar physical properties. This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. 09-ADP09-0016 issued through the Astrophysics Data Analysis Program.

  3. Chandra Observations of Outflows from PSR J1509–5850

    NASA Astrophysics Data System (ADS)

    Klingler, Noel; Kargaltsev, Oleg; Rangelov, Blagoy; Pavlov, George G.; Posselt, Bettina; Ng, C.-Y.

    2016-09-01

    PSR J1509–5850 is a middle-aged pulsar with a period of P ≈ 89 ms and spin-down power of \\dot{E}=5.1× {10}35 erg s‑1, at a distance of about 3.8 kpc. We report on deep Chandra X-ray Observatory observations of this pulsar and its pulsar wind nebula (PWN). In addition to the previously detected tail extending up to 7‧ southwest from the pulsar (the southern outflow), the deep images reveal similarly long, faint, diffuse emission stretched toward the north (the northern outflow) and the fine structure of the compact nebula (CN) in the pulsar vicinity. The CN is resolved into two lateral tails and one axial tail pointing southwest (a morphology remarkably similar to that of the Geminga PWN), which supports the assumption that the pulsar moves toward the northeast. The luminosities of the southern and northern outflows are about 1× {10}33 and 4× {10}32 erg s‑1, respectively. The spectra extracted from four regions of the southern outflow do not show any softening with increasing distance from the pulsar. The lack of synchrotron cooling suggests a high flow speed or in situ acceleration of particles. The spectra extracted from two regions of the northern outflow show a hint of softening with distance from the pulsar, which may indicate slower particle propagation. We speculate that the northern outflow is associated with particle leakage from the bow-shock apex into the ISM, while the southern outflow represents the tail of the shocked pulsar wind behind the moving pulsar. We estimate the physical parameters of the observed outflows and compare the J1509–5850 PWN with PWNe of other supersonically moving pulsars.

  4. Characterization of molecular outflows in the substellar domain

    SciTech Connect

    Phan-Bao, Ngoc; Dang-Duc, Cuong; Lee, Chin-Fei; Ho, Paul T. P.; Li, Di E-mail: pbngoc@asiaa.sinica.edu.tw

    2014-11-01

    We report here our latest search for molecular outflows from young brown dwarfs and very low-mass stars in nearby star-forming regions. We have observed three sources in Taurus with the Submillimeter Array and the Combined Array for Research in Millimeter-wave Astronomy at 230 GHz frequency to search for CO J = 2 → 1 outflows. We obtain a tentative detection of a redshifted and extended gas lobe at about 10 arcsec from the source GM Tau, a young brown dwarf in Taurus with an estimated mass of 73 M {sub J}, which is right below the hydrogen-burning limit. No blueshifted emission around the brown dwarf position is detected. The redshifted gas lobe that is elongated in the northeast direction suggests a possible bipolar outflow from the source with a position angle of about 36°. Assuming that the redshifted emission is outflow emission from GM Tau, we then estimate a molecular outflow mass in the range from 1.9 × 10{sup –6} M {sub ☉} to 2.9 × 10{sup –5} M {sub ☉} and an outflow mass-loss rate from 2.7 × 10{sup –9} M {sub ☉} yr{sup –1} to 4.1 × 10{sup –8} M {sub ☉} yr{sup –1}. These values are comparable to those we have observed in the young brown dwarf ISO-Oph 102 of 60 M {sub J} in ρ Ophiuchi and the very low-mass star MHO 5 of 90 M {sub J} in Taurus. Our results suggest that the outflow process in very low-mass objects is episodic with a duration of a few thousand years and the outflow rate of active episodes does not significantly change for different stages of the formation process of very low-mass objects. This may provide us with important implications that clarify the formation process of brown dwarfs.

  5. Chandra Observations of Outflows from PSR J1509-5850

    NASA Astrophysics Data System (ADS)

    Klingler, Noel; Kargaltsev, Oleg; Rangelov, Blagoy; Pavlov, George G.; Posselt, Bettina; Ng, C.-Y.

    2016-09-01

    PSR J1509-5850 is a middle-aged pulsar with a period of P ≈ 89 ms and spin-down power of \\dot{E}=5.1× {10}35 erg s-1, at a distance of about 3.8 kpc. We report on deep Chandra X-ray Observatory observations of this pulsar and its pulsar wind nebula (PWN). In addition to the previously detected tail extending up to 7‧ southwest from the pulsar (the southern outflow), the deep images reveal similarly long, faint, diffuse emission stretched toward the north (the northern outflow) and the fine structure of the compact nebula (CN) in the pulsar vicinity. The CN is resolved into two lateral tails and one axial tail pointing southwest (a morphology remarkably similar to that of the Geminga PWN), which supports the assumption that the pulsar moves toward the northeast. The luminosities of the southern and northern outflows are about 1× {10}33 and 4× {10}32 erg s-1, respectively. The spectra extracted from four regions of the southern outflow do not show any softening with increasing distance from the pulsar. The lack of synchrotron cooling suggests a high flow speed or in situ acceleration of particles. The spectra extracted from two regions of the northern outflow show a hint of softening with distance from the pulsar, which may indicate slower particle propagation. We speculate that the northern outflow is associated with particle leakage from the bow-shock apex into the ISM, while the southern outflow represents the tail of the shocked pulsar wind behind the moving pulsar. We estimate the physical parameters of the observed outflows and compare the J1509-5850 PWN with PWNe of other supersonically moving pulsars.

  6. Identifying the Main Driver of Active Region Outflows

    NASA Astrophysics Data System (ADS)

    Baker, D.; van Driel-Gesztelyi, L.; Mandrini, C. H.; Démoulin, P.; Murray, M. J.

    2012-08-01

    Hinode's EUV Imaging Spectrometer (EIS) has discovered ubiquitous outflows of a few to 50 km s-1 from active regions (ARs). The characteristics of these outflows are very curious in that they are most prominent at the AR boundary and appear over monopolar magnetic areas. They are linked to strong non-thermal line broadening and are stronger in hotter EUV lines. The outflows persist for at least several days. Whereas red-shifted down flows observed in AR closed loops are well understood, to date there is no general consensus for the mechanism(s) driving blue-shifted AR-related outflows. We use Hinode EIS and X-Ray Telescope observations of AR 10942 coupled with magnetic modeling to demonstrate for the first time that the outflows originate from specific locations of the magnetic topology where field lines display strong gradients of magnetic connectivity, namely quasi-separatrix layers (QSLs), or in the limit of infinitely thin QSLs, separatrices. The strongest AR outflows were found to be in the vicinity of QSL sections located over areas of strong magnetic field. We argue that magnetic reconnection at QSLs, separating closed field lines of the AR and either large-scale externally connected or ‘open’ field lines, is a viable mechanism for driving AR outflows which are potentially sources of the slow solar wind. In fact, magnetic reconnection along QSLs (including separatricies) is the first theory to explain the most puzzling characteristics of the outflows, namely their occurrence over monopolar areas at the periphery of ARs and their longevity.

  7. AH-64 IHADSS aviator vision experiences in Operation Iraqi Freedom

    NASA Astrophysics Data System (ADS)

    Hiatt, Keith L.; Rash, Clarence E.; Harris, Eric S.; McGilberry, William H.

    2004-09-01

    Forty AH-64 Apache aviators representing a total of 8564 flight hours and 2260 combat hours during Operation Iraqi Freedom and its aftermath were surveyed for their visual experiences with the AH-64's monocular Integrated Helmet and Display Sighting System (IHADSS) helmet-mounted display in a combat environment. A major objective of this study was to determine if the frequencies of reports of visual complaints and illusions reported in the previous studies, addressing mostly benign training environments, differ in the more stressful combat environments. The most frequently reported visual complaints, both while and after flying, were visual discomfort and headache, which is consistent with previous studies. Frequencies of complaints after flying in the current study were numerically lower for all complaint types, but differences from previous studies are statistically significant only for visual discomfort and disorientation (vertigo). With the exception of "brownout/whiteout," reports of degraded visual cues in the current study were numerically lower for all types, but statistically significant only for impaired depth perception, decreased field of view, and inadvertent instrumental meteorological conditions. This study also found statistically lower reports of all static and dynamic illusions (with one exception, disorientation). This important finding is attributed to the generally flat and featureless geography present in a large portion of the Iraqi theater and to the shift in the way that the aviators use the two disparate visual inputs presented by the IHADSS monocular design (i.e., greater use of both eyes as opposed to concentrating primarily on display imagery).

  8. Aeroelastic characteristics of the AH-64 bearingless tail rotor

    NASA Technical Reports Server (NTRS)

    Banerjee, D.

    1988-01-01

    The results of a wind tunnel test program to determine the performance loads and dynamic characteristics of the Composite Flexbeam Tail Rotor (CFTR) for the AH-64 Advanced Attack Helicopter are reported. The CFTR uses an elastomeric shear attachment of the flexbeam to the hub to provide soft-inplane S-mode and stiff-inplane C-mode configuration. The properties of the elastomer were selected for proper frequency placement and scale damping of the inplane S-mode. Kinematic pitch-lag coupling was introduced to provide the first cyclic inplane C-mode damping at high collective pitch. The CFTR was tested in a wind tunnel over the full slideslip envelop of the AH-64. It is found that the rotor was aeroelastically stable throughout the complete collective pitch range and up to rotor speeds of 1403 rpm. The dynamic characteristics of the rotor were found to be satisfactory at all pitch angles and rotor speeds of the tunnel tests. The design characteristics of the rotor which permit the high performance characteristics are discussed. Several schematic drawings and photographs of the rotor are provided.

  9. In Vivo Near-Infrared Fluorescence Imaging of Aqueous Humor Outflow Structures

    PubMed Central

    Zeppa, L.; Ambrosone, L.; Guerra, G.; Fortunato, M.

    2016-01-01

    The aim of this study has been to visualize the aqueous outflow system in patients affected by primary open angle glaucoma. A solution of indocyanine green (ICG) plus high viscosity viscoelastic solution was injected into the Schlemm canal during surgery in 10 glaucomatous patients undergoing canaloplasty. Soon after injection of the dye the borders of the scleral flap were completely stained due to partial reflux caused by the intrachannel resistance; progression of the dye along the Schlemm canal starting from the site of injection was then visualized. The filling of the collector channels was observed only in the patent portions of the Schlemm canal. The only noticeable aqueous veins were located in correspondence of the quadrant in which both the Schlemm canal and the collectors were patent. Lastly, a retrograde filling, of glomerular-shaped structures, deepest to the Schlemm canal was observed in the quadrants where the pathway was functioning. Our findings show that injection of a mixture composed of ICG and viscoelastic solution into the Schlemm canal allows a clear visualization of the functioning portions of the conventional outflow pathway. In addition, a retrograde filling of structures presumably located into the iris was also recorded. Clinical Trial Registration. Our study is registered in ISRCTN registry, number 54005880, DOI 10.1186/ISRCTN54005880. PMID:27313871

  10. The Implications of Extreme Outflows from Extreme Starbursts

    NASA Astrophysics Data System (ADS)

    Heckman, Timothy M.; Borthakur, Sanchayeeta

    2016-05-01

    Interstellar ultraviolet absorption lines provide crucial information about the properties of galactic outflows. In this paper, we augment our previous analysis of the systematic properties of starburst-driven galactic outflows by expanding our sample to include a rare population of starbursts with exceptionally high outflow velocities. In principle, these could be a qualitatively different phenomenon from more typical outflows. However, we find that instead these starbursts lie on, or along the extrapolation of, the trends defined by the more typical systems studied previously by us. We exploit the wide dynamic range provided by this new sample to determine scaling relations of outflow velocity with galaxy stellar mass (M *), circular velocity, star formation rate (SFR), SFR/M *, and SFR/area. We argue that these results can be accommodated within the general interpretational framework we previously advocated, in which a population of ambient interstellar or circumgalactic clouds is accelerated by the combined forces of gravity and the momentum flux from the starburst. We show that this simple physical picture is consistent with both the strong cosmological evolution of galactic outflows in typical star-forming galaxies and the paucity of such galaxies with spectra showing inflows. We also present simple parameterizations of these results that can be implemented in theoretical models and numerical simulations of galaxy evolution.

  11. Estimating the Circulation and Net Plasma Loss from Ionospheric Outflow

    NASA Astrophysics Data System (ADS)

    Haaland, S.; Engwall, E.; Eriksson, A. I.; Nilsson, H.; Foerster, M.; Lybekk, B.; Svenes, K.; Pedersen, A.

    2010-12-01

    An important source of magnetospheric plasma is outflow from the terrestrial ionosphere. Low energy ions travel along the magnetic field lines and enter the magnetospheric lobes and are convected towards the tail plasma sheet. Results from Cluster indicate that the field aligned outflow velocity is sometimes much higher than the convection towards the central plasma sheet. A substantial amount of plasma therefore escape downtail without ever reaching the central plasma sheet. In this work, we use Cluster measurements of the ionospheric outflow and lobe convection velocities combined with a model of the magnetic field in an attempt to quantify the plasma loss for various magnetospheric conditions. The results show that both the circulation of plasma but also the tailward escape of ions increase significantly during disturbed magnetospheric conditions. For strong solar wind driving with a southward interplanetary magnetic field, also typically associated with high geomagnetic activity, most of the outflowing plasma are convected to the plasma sheet and recirculated. For periods with northward interplanetary magnetic field, the convection is nearly stagnant, whereas the outflow, although limited, still persist. During such conditions, the outflowing ions escape downtail and are lost into the solar wind.

  12. A COMPLETE Search for Molecular Outflows in Perseus

    NASA Astrophysics Data System (ADS)

    Fallscheer, C.; Borkin, M.; Ridge, N.; Schnee, S.; Goodman, A.

    2003-12-01

    Using 12CO data collected in the Coordinated Molecular Probe Line Extinction Thermal Emission (COMPLETE) Survey, we have carried out an unbiased search for molecular outflows. To begin the search, we analyzed maps of the Spectral Correlation Function (SCF) of the 12CO spectra, at a variety of spatial lags. The known outflows were all apparent in the SCF maps as regions of either very low or very high spectral correlation. Other regions identified by the SCF as having low or high spectral correlation in the data cube were examined by hand in order to assess the possibility that they harbored previously unknown outflows. Upon making customized "channel" maps of these 15 suspect regions, we have now confidently identified 4 new outflows, and 11 other regions with unusual spectral properties potentially associated with outflow. This work is still in progress, but we can say with certainty that COMPLETE has identified several new molecular outflows in Perseus. This work was supported in part by the SAO intern program under NSF grant AST-9731923.

  13. On the physical origin of AGN outflow driving mechanisms

    NASA Astrophysics Data System (ADS)

    Ishibashi, Wako

    2016-07-01

    Super-massive black holes in active galactic nuclei (AGN) respond to the accretion process by feeding back energy and momentum into the surrounding environment. Galaxy-scale outflows are thought to provide the physical link connecting the small scales of the central black hole to the large scales of the host galaxy. Such powerful outflows are now starting to be commonly observed, and have been considered as a proof of AGN feedback in action. However, the physical origin of the mechanism driving the observed outflows is still unclear, and whether it is due to energy-driving or radiation-driving is a source of much debate in the literature. We consider AGN feedback driven by radiation pressure on dust, and show that AGN radiative feedback is capable of driving powerful outflows on galactic scales. In particular, we can obtain outflowing shells with high velocity and large momentum flux, by properly taking into account the effects of radiation trapping. Alternatively, the observed outflow characteristics may be significantly biased by AGN variability. I will discuss the resulting implications in the global context of black hole accretion-AGN feedback coupling.

  14. MOS Mapping of the NIR Outflow HH 223

    NASA Astrophysics Data System (ADS)

    López, R.; Acosta-Pulido, J. A.; Estalella, R.; Gómez, G.; García-Lorenzo, B.

    2016-10-01

    The Multi-Object-Spectroscopy (MOS) mode of LIRIS was used to map the near-IR stellar outflow HH 223, in the dark cloud Lynds 723 (L723). HH 223 spatially coincides with the east-west component of the L723 quadrupolar CO outflow. The radio continuum source SMA2, towards the center of the quadrupolar CO outflow, hides the YSO that seems to power both the near-IR and the CO outflows. To map the S-shaped, near-IR emission of HH 223, extending ˜ 5', an appropriate mask was designed, with 16 rectangular slitlets. J, H and K-band spectra (R ˜eq 2500) were obtained through the mask. The kinematics of the neutral (H2) and ionized ([FeII]) gas outflow was derived from these data. The results confirm that both the near-IR and the CO outflows have a common driving source. To our knowledge, this is the first use of the MOS-LIRIS observing mode with the mask designed ad hoc to fit several extended, nonaligned targets.

  15. Detecting Spread of Avian Influenza A(H7N9) Virus Beyond China.

    PubMed

    Millman, Alexander J; Havers, Fiona; Iuliano, A Danielle; Davis, C Todd; Sar, Borann; Sovann, Ly; Chin, Savuth; Corwin, Andrew L; Vongphrachanh, Phengta; Douangngeun, Bounlom; Lindblade, Kim A; Chittaganpitch, Malinee; Kaewthong, Viriya; Kile, James C; Nguyen, Hien T; Pham, Dong V; Donis, Ruben O; Widdowson, Marc-Alain

    2015-05-01

    During February 2013-March 2015, a total of 602 human cases of low pathogenic avian influenza A(H7N9) were reported; no autochthonous cases were reported outside mainland China. In contrast, since highly pathogenic avian influenza A(H5N1) reemerged during 2003 in China, 784 human cases in 16 countries and poultry outbreaks in 53 countries have been reported. Whether the absence of reported A(H7N9) outside mainland China represents lack of spread or lack of detection remains unclear. We compared epidemiologic and virologic features of A(H5N1) and A(H7N9) and used human and animal influenza surveillance data collected during April 2013-May 2014 from 4 Southeast Asia countries to assess the likelihood that A(H7N9) would have gone undetected during 2014. Surveillance in Vietnam and Cambodia detected human A(H5N1) cases; no A(H7N9) cases were detected in humans or poultry in Southeast Asia. Although we cannot rule out the possible spread of A(H7N9), substantial spread causing severe disease in humans is unlikely.

  16. Detecting Spread of Avian Influenza A(H7N9) Virus Beyond China

    PubMed Central

    Havers, Fiona; Iuliano, A. Danielle; Davis, C. Todd; Sar, Borann; Sovann, Ly; Chin, Savuth; Corwin, Andrew L.; Vongphrachanh, Phengta; Douangngeun, Bounlom; Lindblade, Kim A.; Chittaganpitch, Malinee; Kaewthong, Viriya; Kile, James C.; Nguyen, Hien T.; Pham, Dong V.; Donis, Ruben O.; Widdowson, Marc-Alain

    2015-01-01

    During February 2013–March 2015, a total of 602 human cases of low pathogenic avian influenza A(H7N9) were reported; no autochthonous cases were reported outside mainland China. In contrast, since highly pathogenic avian influenza A(H5N1) reemerged during 2003 in China, 784 human cases in 16 countries and poultry outbreaks in 53 countries have been reported. Whether the absence of reported A(H7N9) outside mainland China represents lack of spread or lack of detection remains unclear. We compared epidemiologic and virologic features of A(H5N1) and A(H7N9) and used human and animal influenza surveillance data collected during April 2013–May 2014 from 4 Southeast Asia countries to assess the likelihood that A(H7N9) would have gone undetected during 2014. Surveillance in Vietnam and Cambodia detected human A(H5N1) cases; no A(H7N9) cases were detected in humans or poultry in Southeast Asia. Although we cannot rule out the possible spread of A(H7N9), substantial spread causing severe disease in humans is unlikely. PMID:25897654

  17. Methylated pentavalent arsenic metabolites are bifunctional inducers, as they induce cytochrome P450 1A1 and NAD(P)H:quinone oxidoreductase through AhR- and Nrf2-dependent mechanisms.

    PubMed

    Anwar-Mohamed, Anwar; Elshenawy, Osama H; Soshilov, Anatoly A; Denison, Michael S; Chris Le, X; Klotz, Lars-Oliver; El-Kadi, Ayman O S

    2014-02-01

    Activation of the aryl hydrocarbon receptor (AhR) ultimately leads to the induction of the carcinogen-activating enzyme cytochrome P450 1A1 (CYP1A1), and activation of the nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) in addition to the AhR pathway induces the expression of the NADP(H):quinone oxidoreductase (NQO1). Therefore, the aim of this study was to examine the effect of As(III) pentavalent metabolites, MMA(V), DMA(V), and TMA(V), on AhR and Nrf2 activation and on the expression of their prototypical downstream targets CYP1A1 and NQO1, respectively. Our results showed that treatment of HepG2 cells with MMA(V), DMA(V), or TMA(V) in the absence and presence of 2,3,7,8-tetrachlorodibenzo-p-dioxin or sulforaphane significantly induced both CYP1A1 and NQO1 at the mRNA, protein, and catalytic activity levels. Furthermore, these metabolites increased the AhR-dependent XRE-driven and the Nrf2-dependent ARE-driven luciferase reporter activities, which coincided with increased nuclear accumulation of both transcription factors. However, none of these metabolites were shown to be AhR ligands. The induction of CYP1A1 by these metabolites seems to be ligand-independent, possibly through a decrease in HSP90 protein expression levels. The metabolites also increased ROS production, which was significantly higher than that produced by As(III). Upon knockdown of AhR and Nrf2 the MMA(V)-, DMA(V)-, and TMA(V)-mediated induction of both CYP1A1 and NQO1 proteins was significantly decreased. In conclusion, this study demonstrates for the first time that methylated pentavalent arsenic metabolites are bifunctional inducers, as they increase CYP1A1 by activating the AhR/XRE signaling pathway and they increase NQO1 by activating the Nrf2/ARE signaling pathway in addition to the AhR/XRE pathway.

  18. Radiation Transport for Explosive Outflows: Opacity Regrouping

    NASA Astrophysics Data System (ADS)

    Wollaeger, Ryan T.; van Rossum, Daniel R.

    2014-10-01

    Implicit Monte Carlo (IMC) and Discrete Diffusion Monte Carlo (DDMC) are methods used to stochastically solve the radiative transport and diffusion equations, respectively. These methods combine into a hybrid transport-diffusion method we refer to as IMC-DDMC. We explore a multigroup IMC-DDMC scheme that in DDMC, combines frequency groups with sufficient optical thickness. We term this procedure "opacity regrouping." Opacity regrouping has previously been applied to IMC-DDMC calculations for problems in which the dependence of the opacity on frequency is monotonic. We generalize opacity regrouping to non-contiguous groups and implement this in SuperNu, a code designed to do radiation transport in high-velocity outflows with non-monotonic opacities. We find that regrouping of non-contiguous opacity groups generally improves the speed of IMC-DDMC radiation transport. We present an asymptotic analysis that informs the nature of the Doppler shift in DDMC groups and summarize the derivation of the Gentile-Fleck factor for modified IMC-DDMC. We test SuperNu using numerical experiments including a quasi-manufactured analytic solution, a simple 10 group problem, and the W7 problem for Type Ia supernovae. We find that opacity regrouping is necessary to make our IMC-DDMC implementation feasible for the W7 problem and possibly Type Ia supernova simulations in general. We compare the bolometric light curves and spectra produced by the SuperNu and PHOENIX radiation transport codes for the W7 problem. The overall shape of the bolometric light curves are in good agreement, as are the spectra and their evolution with time. However, for the numerical specifications we considered, we find that the peak luminosity of the light curve calculated using SuperNu is ~10% less than that calculated using PHOENIX.

  19. Magnetic Fields and Outflows from AGN Disks

    NASA Astrophysics Data System (ADS)

    Lovelace, Richard V. E.; Bisnovatyi-Kogan, Gennady S.; Rothstein, D. M.

    2010-11-01

    Activity of the nuclei of galaxies involving disk accretion to black holes is thought to be due to (1) a small-scale turbulent magnetic field in the disk (due to the magneto-rotational instability or MRI) which gives a large viscosity enhancing accretion, and (2) a large-scale magnetic field which gives rise to matter outflows and/or electromagnetic jets from the disk which also enhances accretion. An important problem with this picture is that the enhanced viscosity is accompanied by an enhanced magnetic diffusivity which acts to prevent the build up of a significant large-scale field. Recent work has pointed out that the disk's surface layers are non-turbulent and thus highly conducting (or non-diffusive) because the MRI is suppressed high in the disk where the magnetic and radiation pressures are larger than the thermal pressure. Here, we calculate the vertical (Z) profiles of the stationary accretion flows (with radial and azimuthal components), and the profiles of the large-scale, magnetic field taking into account the turbulent viscosity and diffusivity due to the MRI and the fact that the turbulence vanishes at the surface of the disk. We derive a sixth-order differential equation for the radial flow velocity vr (Z) which depends mainly on the midplane thermal to magnetic pressure ratio ˜>1 and the Prandtl number of the turbulence P = viscosity/diffusivity. Boundary conditions at the disk surface take into account a possible magnetic wind or jet and allow for a surface current in the highly conducting surface layer. The stationary solutions we find indicate that a weak (˜>1) large-scale field does not di use away as suggested by earlier work.

  20. RADIATION TRANSPORT FOR EXPLOSIVE OUTFLOWS: OPACITY REGROUPING

    SciTech Connect

    Wollaeger, Ryan T.; Van Rossum, Daniel R. E-mail: daan@flash.uchicago.edu

    2014-10-01

    Implicit Monte Carlo (IMC) and Discrete Diffusion Monte Carlo (DDMC) are methods used to stochastically solve the radiative transport and diffusion equations, respectively. These methods combine into a hybrid transport-diffusion method we refer to as IMC-DDMC. We explore a multigroup IMC-DDMC scheme that in DDMC, combines frequency groups with sufficient optical thickness. We term this procedure ''opacity regrouping''. Opacity regrouping has previously been applied to IMC-DDMC calculations for problems in which the dependence of the opacity on frequency is monotonic. We generalize opacity regrouping to non-contiguous groups and implement this in SuperNu, a code designed to do radiation transport in high-velocity outflows with non-monotonic opacities. We find that regrouping of non-contiguous opacity groups generally improves the speed of IMC-DDMC radiation transport. We present an asymptotic analysis that informs the nature of the Doppler shift in DDMC groups and summarize the derivation of the Gentile-Fleck factor for modified IMC-DDMC. We test SuperNu using numerical experiments including a quasi-manufactured analytic solution, a simple 10 group problem, and the W7 problem for Type Ia supernovae. We find that opacity regrouping is necessary to make our IMC-DDMC implementation feasible for the W7 problem and possibly Type Ia supernova simulations in general. We compare the bolometric light curves and spectra produced by the SuperNu and PHOENIX radiation transport codes for the W7 problem. The overall shape of the bolometric light curves are in good agreement, as are the spectra and their evolution with time. However, for the numerical specifications we considered, we find that the peak luminosity of the light curve calculated using SuperNu is ∼10% less than that calculated using PHOENIX.

  1. Quasar Outflows and Black Hole Masses

    NASA Astrophysics Data System (ADS)

    Coatman, Liam; Hewett, Paul; Banerji, Manda; Richards, Gordon; Hennawi, Joseph; Prochaska, Jason X.

    2016-08-01

    Black-hole masses are crucial to understanding the physics of the connection between quasars and their host galaxies and measuring cosmic black hole-growth. At high redshift, z > 2, black hole masses are normally derived using the velocity-width of the CIV broad emission line, based on the assumption that the observed velocity-widths arise from virial-induced motions. In many quasars, the CIV-emission line exhibits significant blue asymmetries ('blueshifts') with the line centroid displaced by up to thousands of km/s to the blue. These blueshifts almost certainly signal the presence of strong outflows, most likely originating in a disc wind. Using both archival data and new observations, we have obtained near-infrared spectra, including the Ha and/or Hb emission lines, for ~400 luminous (L_Bol = 45.5-48.5 erg/s) SDSS quasars, at redshifts 1.5 < z < 4, with CIV emission lines spanning the full-range of blueshifts present in the population. A strong correlation between CIV-velocity width and blueshift is found and, at large blueshifts, >2000 km/s, the velocity-widths appear to be dominated by non-virial motions. Using the Ha/Hb emission to provide black hole masses free from non-virial contributions, we are able to derive a quantitative correction to the CIV-based black-hole masses as a function of blueshift. This correction reduces the scatter between Ha/Hb and CIV velocity widths to just ~0.1 dex. Without the correction, black hole masses would be overestimated by a factor of nine at the largest blueshifts. With a suitable systemic redshift-estimation algorithm, this correction can be straightforwardly applied based only on information contained in the rest-frame UV spectra.

  2. Unique Expression of Angiotensin Type-2 Receptor in Sex-Specific Distribution of Myelinated Ah-Type Baroreceptor Neuron Contributing to Sex-Dimorphic Neurocontrol of Circulation.

    PubMed

    Liu, Yang; Zhou, Jia-Ying; Zhou, Yu-Hong; Wu, Di; He, Jian-Li; Han, Li-Min; Liang, Xiao-Bo; Wang, Lu-Qi; Lu, Xiao-Long; Chen, Hanying; Qiao, Guo-Fen; Shou, Weinian; Li, Bai-Yan

    2016-04-01

    This study aims to understand the special expression patterns of angiotensin-II receptor (AT1R and AT2R) in nodose ganglia and nucleus of tractus solitary of baroreflex afferent pathway and their contribution in sex difference of neurocontrol of blood pressure regulation. In this regard, action potentials were recorded in baroreceptor neurons (BRNs) using whole-cell patch techniques; mRNA and protein expression of AT1R and AT2R in nodose ganglia and nucleus of tractus solitary were evaluated using real time-polymerase chain reaction, Western blot, and immunohistochemistry at both tissue and single-cell levels. The in vivo effects of 17β-estradiol on blood pressure and AT2R expression were also tested. The data showed that AT2R, rather than AT1R, expression was higher in female than age-matched male rats. Moreover, AT2R was downregulated in ovariectomized rats, which was restored by the administration of 17β-estradiol. Single-cell real time-polymerase chain reaction data indicated that AT2R was uniquely expressed in Ah-type BRNs. Functional study showed that long-term administration of 17β-estradiol significantly alleviated the blood pressure increase in ovariectomized rats. Electrophysiological recordings showed that angiotensin-II treatment increased the neuroexcitability more in Ah- than C-type BRNs, whereas no such effect was observed in A-types. In addition, angiotensin-II treatment prolonged action potential duration, which was not further changed by iberiotoxin. The density of angiotensin-II-sensitive K(+) currents recorded in Ah-types was equivalent with iberiotoxin-sensitive component. In summary, the unique, sex- and afferent-specific expression of AT2R was identified in Ah-type BRNs, and AT2R-mediated KCa1.1 inhibition in Ah-type BRNs may exert great impacts on baroreflex afferent function and blood pressure regulation in females. PMID:26883269

  3. Deciphering Dimerization Modes of PAS Domains: Computational and Experimental Analyses of the AhR:ARNT Complex Reveal New Insights Into the Mechanisms of AhR Transformation

    PubMed Central

    Corrada, Dario; Soshilov, Anatoly A.; Denison, Michael S.

    2016-01-01

    The Aryl hydrocarbon Receptor (AhR) is a transcription factor that mediates the biochemical response to xenobiotics and the toxic effects of a number of environmental contaminants, including dioxins. Recently, endogenous regulatory roles for the AhR in normal physiology and development have also been reported, thus extending the interest in understanding its molecular mechanisms of activation. Since dimerization with the AhR Nuclear Translocator (ARNT) protein, occurring through the Helix-Loop-Helix (HLH) and PER-ARNT-SIM (PAS) domains, is needed to convert the AhR into its transcriptionally active form, deciphering the AhR:ARNT dimerization mode would provide insights into the mechanisms of AhR transformation. Here we present homology models of the murine AhR:ARNT PAS domain dimer developed using recently available X-ray structures of other bHLH-PAS protein dimers. Due to the different reciprocal orientation and interaction surfaces in the different template dimers, two alternative models were developed for both the PAS-A and PAS-B dimers and they were characterized by combining a number of computational evaluations. Both well-established hot spot prediction methods and new approaches to analyze individual residue and residue-pairwise contributions to the MM-GBSA binding free energies were adopted to predict residues critical for dimer stabilization. On this basis, a mutagenesis strategy for both the murine AhR and ARNT proteins was designed and ligand-dependent DNA binding ability of the AhR:ARNT heterodimer mutants was evaluated. While functional analysis disfavored the HIF2α:ARNT heterodimer-based PAS-B model, most mutants derived from the CLOCK:BMAL1-based AhR:ARNT dimer models of both the PAS-A and the PAS-B dramatically decreased the levels of DNA binding, suggesting this latter model as the most suitable for describing AhR:ARNT dimerization. These novel results open new research directions focused at elucidating basic molecular mechanisms underlying the

  4. Kiloparsec-scale outflows are prevalent among luminous AGN: outflows and feedback in the context of the overall AGN population

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.; Alexander, D. M.; Mullaney, J. R.; Swinbank, A. M.

    2014-07-01

    We present integral field unit observations covering the [O III]λλ4959, 5007 and Hβ emission lines of 16 z < 0.2 type 2 active galactic nuclei (AGN). Our targets are selected from a well-constrained parent sample of ≈24 000 AGN so that we can place our observations into the context of the overall AGN population. Our targets are radio quiet with star formation rates (SFRs; ≲[10-100] M⊙ yr-1) that are consistent with normal star-forming galaxies. We decouple the kinematics of galaxy dynamics and mergers from outflows. We find high-velocity ionized gas (velocity widths ≈600-1500 km s-1; maximum velocities ≤1700 km s-1) with observed spatial extents of ≳(6-16) kpc in all targets and observe signatures of spherical outflows and bi-polar superbubbles. We show that our targets are representative of z < 0.2, luminous (i.e. L[O III] > 1041.7 erg s-1) type 2 AGN and that ionized outflows are not only common but also in ≥70 per cent (3σ confidence) of cases, they are extended over kiloparsec scales. Our study demonstrates that galaxy-wide energetic outflows are not confined to the most extreme star-forming galaxies or radio-luminous AGN; however, there may be a higher incidence of the most extreme outflow velocities in quasars hosted in ultraluminous infrared galaxies. Both star formation and AGN activity appear to be energetically viable to drive the outflows and we find no definitive evidence that favours one process over the other. Although highly uncertain, we derive mass outflow rates (typically ≈10 times the SFRs), kinetic energies (≈0.5-10 per cent of LAGN) and momentum rates (typically ≳10-20 × LAGN/c) consistent with theoretical models that predict AGN-driven outflows play a significant role in shaping the evolution of galaxies.

  5. Involvement of a non-CB1/CB2 cannabinoid receptor in the aqueous humor outflow-enhancing effects of abnormal-cannabidiol.

    PubMed

    Qiao, Zhuanhong; Kumar, Akhilesh; Kumar, Pritesh; Song, Zhao-Hui

    2012-07-01

    The purpose of this study was to investigate the effects of abnormal-cannabidiol (abn-cbd), a non-psychoactive cannabinoid agonist, on aqueous humor outflow via the trabecular meshwork (TM) of porcine eye, and to examine the involvement of a non-CB1/CB2 cannabinoid receptor and the p42/44 mitogen-activated protein kinase (p42/44 MAPK) pathway. The effects of abn-cbd on aqueous humor outflow were measured using a porcine anterior segment perfused organ culture model. The activation of p42/44 MAPK by abn-cbd was determined in cultured TM cells with western blot analysis using an anti-phospho-p42/44 MAPK antibody. Administration of abn-cbd caused a concentration-dependent enhancement of aqueous humor outflow facility with a maximum effect (155.0 ± 11.7% of basal outflow facility) after administration of 30 nM abn-cbd. Pretreatment with 1 μM of O-1918, a cannabidiol analog that acts as a selective antagonist at the non-CB1/CB2 receptor, produced a full antagonism of 30 nM abn-cbd induced increase of aqueous humor outflow facility. Pretreatment with 1 μM of CB1 antagonist SR141716A partially blocked, whereas pretreatment with either 1 μM of CB1 antagonist AM251 or 1 μM of CB2 antagonist SR144528 had no effect on abn-cbd induced enhancement of outflow facility. Treatment of TM cells with 30 nM of abn-cbd activated p42/44 MAPK, which was blocked completely by pretreatment with O-1918, and partially by pretreatment with SR141716A, but not by either AM251 or SR144528. In addition, PD98059, an inhibitor of p42/44 MAPK pathway, blocked completely the abn-cbd induced p42/44 MAPK activation and blocked partially the abn-cbd induced enhancement of outflow facility. In conclusion, the results from this study demonstrate that abn-cbd increases aqueous humor outflow through the TM pathway of the eye, and this effect is mediated by a non-CB1/CB2 cannabinoid receptor, with an involvement of p42/44 MAPK signaling pathway.

  6. Involvement of a non-CB1/CB2 cannabinoid receptor in the aqueous humor outflow-enhancing effects of abnormal-cannabidiol

    PubMed Central

    Qiao, Zhuanhong; Kumar, Akhilesh; Kumar, Pritesh; Song, Zhao-Hui

    2016-01-01

    The purpose of this study was to investigate the effects of abnormal-cannabidiol (abn-cbd), a non-psychoactive cannabinoid agonist, on aqueous humor outflow via the trabecular meshwork (TM) of porcine eye, and to examine the involvement of a non-CB1/CB2 cannabinoid receptor and the p42/44 mitogen-activated protein kinase (p42/44 MAPK) pathway. The effects of abn-cbd on aqueous humor outflow were measured using a porcine anterior segment perfused organ culture model. The activation of p42/44 MAPK by abn-cbd was determined in cultured TM cells with western blot analysis using an anti-phospho-p42/44 MAPK antibody. Administration of abn-cbd caused a concentration-dependent enhancement of aqueous humor outflow facility with a maximum effect (155.0 ± 11.7% of basal outflow facility) after administration of 30 nM abn-cbd. Pretreatment with 1 μM of O-1918, a cannabidiol analog that acts as a selective antagonist at the non-CB1/CB2 receptor, produced a full antagonism of 30 nM abn-cbd induced increase of aqueous humor outflow facility. Pretreatment with 1 μM of CB1 antagonist SR141716A partially blocked, whereas pretreatment with either 1 μM of CB1 antagonist AM251 or 1 μM of CB2 antagonist SR144528 had no effect on abn-cbd induced enhancement of outflow facility. Treatment of TM cells with 30 nM of abn-cbd activated p42/44 MAPK, which was blocked completely by pretreatment with O-1918, and partially by pretreatment with SR141716A, but not by either AM251 or SR144528. In addition, PD98059, an inhibitor of p42/44 MAPK pathway, blocked completely the abn-cbd induced p42/44 MAPK activation and blocked partially the abn-cbd induced enhancement of outflow facility. In conclusion, the results from this study demonstrate that abn-cbd increases aqueous humor outflow through the TM pathway of the eye, and this effect is mediated by a non-CB1/CB2 cannabinoid receptor, with an involvement of p42/44 MAPK signaling pathway. PMID:22580290

  7. Evidence for a chemically differentiated outflow in Mrk 231

    NASA Astrophysics Data System (ADS)

    Lindberg, J. E.; Aalto, S.; Muller, S.; Martí-Vidal, I.; Falstad, N.; Costagliola, F.; Henkel, C.; van der Werf, P.; García-Burillo, S.; González-Alfonso, E.

    2016-03-01

    Aims: Our goal is to study the chemical composition of the outflows of active galactic nuclei and starburst galaxies. Methods: We obtained high-resolution interferometric observations of HCN and HCO+J = 1 → 0 and J = 2 → 1 of the ultra-luminous infrared galaxy Mrk 231 with the IRAM Plateau de Bure Interferometer. We also use previously published observations of HCN and HCO+J = 1 → 0 and J = 3 → 2, and HNC J = 1 → 0 in the same source. Results: In the line wings of the HCN, HCO+, and HNC emission, we find that these three molecular species exhibit features at distinct velocities which differ between the species. The features are not consistent with emission lines of other molecular species. Through radiative transfer modelling of the HCN and HCO+ outflow emission we find an average abundance ratio X(HCN) /X(HCO+) ≳ 1000. Assuming a clumpy outflow, modelling of the HCN and HCO+ emission produces strongly inconsistent outflow masses. Conclusions: Both the anti-correlated outflow features of HCN and HCO+ and the different outflow masses calculated from the radiative transfer models of the HCN and HCO+ emission suggest that the outflow is chemically differentiated. The separation between HCN and HCO+ could be an indicator of shock fronts present in the outflow, since the HCN/HCO+ ratio is expected to be elevated in shocked regions. Our result shows that studies of the chemistry in large-scale galactic outflows can be used to better understand the physical properties of these outflows and their effects on the interstellar medium in the galaxy. Based on observations with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).Reduced datacubes as FITS files are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/587/A15

  8. Molecular evidence for the existence of an aryl hydrocarbon receptor pathway in scallops Chlamys farreri.

    PubMed

    Cai, Yuefeng; Pan, Luqing; Miao, Jingjing

    2016-01-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that controls the expression of a diverse set of genes. In this study we cloned full-length cDNAs encoding an AhR homologue (designated CfAhR, Accession number: FJ588640) from scallop Chlamys farreri. The CfAhR sequence was constituted by an open reading frame (ORF) of 2466bp encoding 821 amino acids. The predicted molecular weight was 93.0kDa. The CfAhR showed a high conservation of the residues and domains essential to the function of AhR, including basic helix-loop-helix (bHLH) and Per-ARNT-Sim (PAS) domains. Phylogenetic analysis demonstrated that it was clustered within the invertebrate AhR branch. CfAhR expression was detected in gill, digestive gland, ovary, spermary, mantle and adductor, and the highest transcription level was observed in gill. Recombinant plasmid CfAhR-pET32a (designated rCfAhR) was successfully expressed in Escherichia coli BL21. To investigate the molecular detoxification mechanism of benzo(a)pyrene (BaP) detoxification-related genes (AhR; aryl hydrocarbon receptor nuclear translocator, ARNT; heat shock protein 90, HSP90; cytochrome P450 1A1, CYP1A1; glutathione S-transferase pi, GST-pi and P glycoprotein, Pgp) in C. farreri gill, real-time quantitative PCR analysis revealed that the mRNA expression level of CfAhR, xenobiotic-metabolizing enzymes and efflux transporters was induced by BaP and was sensitive to BaP exposure time and concentration, suggesting that BaP influenced the expression of a putative AhR/ARNT signaling pathway in scallops. Our results support the possibility that CfAhR genes are early molecular indicators of BaP through a putative CYP signaling pathway in marine bivalves.

  9. Envelope structure on 700 AU scales and the molecular outflows of low-mass young stellar objects

    NASA Technical Reports Server (NTRS)

    Hogerheijde, M. R.; van Dishoeck, E. F.; Blake, G. A.; van Langevelde, H. J.

    1998-01-01

    IRS 5 outflow, which extends over 10' (0.4 pc), seven of the remaining eight sources are found to drive 12CO 3-2 outflows over < or = 1' (0.04 pc); only L1527 IRS has a well-developed outflow of some 3'(0.12 pc). Estimates are obtained for the outflow kinetic luminosity, Lkin, and the flow momentum rate, FCO, applying corrections for line opacity and source inclination. The flow force FCO correlates with the envelope mass and with the 2.7 mm flux of the circumstellar disk. Only a weak correlation is seen with Lbol, while none is found with the relative age of the object as measured by integral Tmb(HCO+ 3-2)dV/Lbol. These trends support the hypothesis that outflows are driven by accretion through a disk, with a global mass infall rate determined by the mass and density of the envelope. The association of compact HCO+ emission with the walls of the outflow cavities indicates that outflows in turn influence the appearance of the envelopes. It is not yet clear, however, whether they are actively involved in sweeping up envelope material, or merely provide a low-opacity pathway for heating radiation to reach into the envelope.

  10. Envelope structure on 700 AU scales and the molecular outflows of low-mass young stellar objects.

    PubMed

    Hogerheijde, M R; van Dishoeck, E F; Blake, G A; van Langevelde, H J

    1998-07-20

    IRS 5 outflow, which extends over 10' (0.4 pc), seven of the remaining eight sources are found to drive 12CO 3-2 outflows over < or = 1' (0.04 pc); only L1527 IRS has a well-developed outflow of some 3'(0.12 pc). Estimates are obtained for the outflow kinetic luminosity, Lkin, and the flow momentum rate, FCO, applying corrections for line opacity and source inclination. The flow force FCO correlates with the envelope mass and with the 2.7 mm flux of the circumstellar disk. Only a weak correlation is seen with Lbol, while none is found with the relative age of the object as measured by integral Tmb(HCO+ 3-2)dV/Lbol. These trends support the hypothesis that outflows are driven by accretion through a disk, with a global mass infall rate determined by the mass and density of the envelope. The association of compact HCO+ emission with the walls of the outflow cavities indicates that outflows in turn influence the appearance of the envelopes. It is not yet clear, however, whether they are actively involved in sweeping up envelope material, or merely provide a low-opacity pathway for heating radiation to reach into the envelope.

  11. OUTFLOW AND HOT DUST EMISSION IN HIGH-REDSHIFT QUASARS

    SciTech Connect

    Wang, Huiyuan; Xing, Feijun; Wang, Tinggui; Zhou, Hongyan; Zhang, Kai; Zhang, Shaohua

    2013-10-10

    Correlations of hot dust emission with outflow properties are investigated, based on a large z ∼ 2 non-broad absorption line quasar sample built from the Wide-field Infrared Survey and the Sloan Digital Sky Survey data releases. We use the near-infrared slope and the infrared to UV luminosity ratio to indicate the hot dust emission relative to the emission from the accretion disk. In our luminous quasars, these hot dust emission indicators are almost independent of the fundamental parameters, such as luminosity, Eddington ratio and black hole mass, but moderately dependent on the blueshift and asymmetry index (BAI) and FWHM of C IV lines. Interestingly, the latter two correlations dramatically strengthen with increasing Eddington ratio. We suggest that, in high Eddington ratio quasars, C IV regions are dominated by outflows so the BAI and FWHM (C IV) can reliably reflect the general properties and velocity of outflows, respectively. In low Eddington ratio quasars, on the other hand, C IV lines are primarily emitted by virialized gas so the BAI and FWHM (C IV) become less sensitive to outflows. Therefore, the correlations for the highest Eddington ratio quasars are more likely to represent the true dependence of hot dust emission on outflows and the correlations for the entire sample are significantly diluted by the low Eddington ratio quasars. Our results show that an outflow with a large BAI or velocity can double the hot dust emission on average. We suggest that outflows either contain hot dust in themselves or interact with the dusty interstellar medium or torus.

  12. Low Altitude Initiation of Ionospheric Upflow and Outflow

    NASA Astrophysics Data System (ADS)

    Burleigh, M.; Zettergren, M. D.; Rowland, D. E.; Klenzing, J.

    2015-12-01

    Significant amounts of ionospheric plasma can be transported to high altitudes (above 1000 km) in response to a variety of plasma heating and uplifting processes. Soft electron precipitation heats ambient, F-region ionospheric electrons creating electron pressure increases and upflows. Strong DC electric fields frictionally heat the ion population also resulting in ion upflows. Lastly, field-aligned thermospheric winds can contribute to ion motion at lower altitudes, while geomagnetically perpendicular winds may affect frictional heating. Once ions have been lifted to high altitudes, transverse ion acceleration by broadband ELF waves can give the upflowing ions sufficient energy to escape into the magnetosphere (ionospheric outflow). This study examines the thermospheric wind regulation of ionospheric upflow and outflow with a focus on how lower ionosphere dynamics feed source populations for transverse energization and determine the types, and amounts, of outflowing ions. The model used here for this study is a 2D ionospheric model based on a modified 16-moment transport description. It solves conservation of mass, momentum, and parallel and perpendicular energy for all relevant ionospheric species. This model encapsulates ionospheric upflow and outflow processes through the inclusion of DC electric fields, and empirical descriptions of heating by soft electron precipitation and BBELF waves. This model is used to conduct a parametric study of neutral wind effects on upflow and outflow and highlights how low-altitude processes affect ion outflow through the regulation of source plasma available to higher altitudes. This model is also used to construct a case study of ion outflows at the nightside polar cap boundary using data from the VISIONS sounding rocket campaign.

  13. Modeling Jet and Outflow Feedback during Star Cluster Formation

    NASA Astrophysics Data System (ADS)

    Federrath, Christoph; Schrön, Martin; Banerjee, Robi; Klessen, Ralf S.

    2014-08-01

    Powerful jets and outflows are launched from the protostellar disks around newborn stars. These outflows carry enough mass and momentum to transform the structure of their parent molecular cloud and to potentially control star formation itself. Despite their importance, we have not been able to fully quantify the impact of jets and outflows during the formation of a star cluster. The main problem lies in limited computing power. We would have to resolve the magnetic jet-launching mechanism close to the protostar and at the same time follow the evolution of a parsec-size cloud for a million years. Current computer power and codes fall orders of magnitude short of achieving this. In order to overcome this problem, we implement a subgrid-scale (SGS) model for launching jets and outflows, which demonstrably converges and reproduces the mass, linear and angular momentum transfer, and the speed of real jets, with ~1000 times lower resolution than would be required without the SGS model. We apply the new SGS model to turbulent, magnetized star cluster formation and show that jets and outflows (1) eject about one-fourth of their parent molecular clump in high-speed jets, quickly reaching distances of more than a parsec, (2) reduce the star formation rate by about a factor of two, and (3) lead to the formation of ~1.5 times as many stars compared to the no-outflow case. Most importantly, we find that jets and outflows reduce the average star mass by a factor of ~ three and may thus be essential for understanding the characteristic mass of the stellar initial mass function.

  14. Tracing inflows and outflows with absorption lines in circumgalactic gas

    NASA Astrophysics Data System (ADS)

    Ford, Amanda Brady; Davé, Romeel; Oppenheimer, Benjamin D.; Katz, Neal; Kollmeier, Juna A.; Thompson, Robert; Weinberg, David H.

    2014-10-01

    We examine how H I and metal absorption lines within low-redshift galaxy haloes trace the dynamical state of circumgalactic gas, using cosmological hydrodynamic simulations that include a well-vetted heuristic model for galactic outflows. We categorize inflowing, outflowing, and ambient gas based on its history and fate as tracked in our simulation. Following our earlier work, showing that the ionization level of absorbers was a primary factor in determining the physical conditions of absorbing gas, we show here that it is also a governing factor for its dynamical state. Low-ionization metal absorbers (e.g. Mg II) tend to arise in gas that will fall on to galaxies within several Gyr, while high-ionization metal absorbers (e.g. O VI) generally trace material that was deposited by outflows many Gyr ago. Inflowing gas is dominated by enriched material that was previously ejected in an outflow; hence, accretion at low redshifts is typically substantially enriched. Recycling wind material is preferentially found closer to galaxies, and is more dominant in lower mass haloes since high-mass haloes have more hot gas that is able to support itself against infall. Low-mass haloes also tend to re-eject more of their accreted material, owing to our outflow prescription that employs higher mass loading factors for lower mass galaxies. Typical H I absorbers trace unenriched ambient material that is not participating in the baryon cycle, but stronger H I absorbers arise in cool, enriched inflowing gas. Instantaneous radial velocity measures of absorbers are generally poor at distinguishing between inflowing and outflowing gas, except in the case of very recent outflows. These results suggest that probing halo gas using a range of absorbers can provide detailed information about the amount and physical conditions of material that is participating in the baryon cycle.

  15. Modeling jet and outflow feedback during star cluster formation

    SciTech Connect

    Federrath, Christoph; Schrön, Martin; Banerjee, Robi; Klessen, Ralf S.

    2014-08-01

    Powerful jets and outflows are launched from the protostellar disks around newborn stars. These outflows carry enough mass and momentum to transform the structure of their parent molecular cloud and to potentially control star formation itself. Despite their importance, we have not been able to fully quantify the impact of jets and outflows during the formation of a star cluster. The main problem lies in limited computing power. We would have to resolve the magnetic jet-launching mechanism close to the protostar and at the same time follow the evolution of a parsec-size cloud for a million years. Current computer power and codes fall orders of magnitude short of achieving this. In order to overcome this problem, we implement a subgrid-scale (SGS) model for launching jets and outflows, which demonstrably converges and reproduces the mass, linear and angular momentum transfer, and the speed of real jets, with ∼1000 times lower resolution than would be required without the SGS model. We apply the new SGS model to turbulent, magnetized star cluster formation and show that jets and outflows (1) eject about one-fourth of their parent molecular clump in high-speed jets, quickly reaching distances of more than a parsec, (2) reduce the star formation rate by about a factor of two, and (3) lead to the formation of ∼1.5 times as many stars compared to the no-outflow case. Most importantly, we find that jets and outflows reduce the average star mass by a factor of ∼ three and may thus be essential for understanding the characteristic mass of the stellar initial mass function.

  16. Supernovae and AGN Driven Galactic Outflows

    NASA Astrophysics Data System (ADS)

    Sharma, Mahavir; Nath, Biman B.

    2013-01-01

    mass scale (Mh ~ 1012-1012.5 M ⊙) that signifies the crossover of AGN domination in outflow properties from starburst activity at lower masses. We find that stellar mass for massive galaxies scales as M sstarfvpropM 0.26 h , and for low-mass galaxies, M sstarfvpropM 5/3 h .

  17. Central serotonin(2B) receptor blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical dopamine outflow.

    PubMed

    Devroye, Céline; Cathala, Adeline; Di Marco, Barbara; Caraci, Filippo; Drago, Filippo; Piazza, Pier Vincenzo; Spampinato, Umberto

    2015-10-01

    The central serotonin2B receptor (5-HT2BR) is currently considered as an interesting pharmacological target for improved treatment of drug addiction. In the present study, we assessed the effect of two selective 5-HT2BR antagonists, RS 127445 and LY 266097, on cocaine-induced hyperlocomotion and dopamine (DA) outflow in the nucleus accumbens (NAc) and the dorsal striatum of freely moving rats. The peripheral administration of RS 127445 (0.16 mg/kg, i.p.) or LY 266097 (0.63 mg/kg, i.p.) significantly reduced basal DA outflow in the NAc shell, but had no effect on cocaine (10 mg/kg, i.p.)-induced DA outflow in this brain region. Also, RS 127445 failed to modify both basal and cocaine-induced DA outflow in the NAc core and the dorsal striatum. Conversely, both 5-HT2BR antagonists reduced cocaine-induced hyperlocomotion. Furthermore, RS 127445 as well as the DA-R antagonist haloperidol (0.1 mg/kg, i.p.) reduced significantly the late-onset hyperlocomotion induced by the DA-R agonist quinpirole (0.5 mg/kg, s.c.). Altogether, these results demonstrate that 5-HT2BR blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical DA outflow. This interaction takes place downstream to DA neurons and could involve an action at the level of dorsostriatal and/or NAc DA transmission, in keeping with the importance of these brain regions in the behavioural responses of cocaine. Overall, this study affords additional knowledge into the regulatory control exerted by the 5-HT2BR on ascending DA pathways, and provides additional support to the proposed role of 5-HT2BRs as a new pharmacological target in drug addiction. PMID:26116760

  18. Central serotonin(2B) receptor blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical dopamine outflow.

    PubMed

    Devroye, Céline; Cathala, Adeline; Di Marco, Barbara; Caraci, Filippo; Drago, Filippo; Piazza, Pier Vincenzo; Spampinato, Umberto

    2015-10-01

    The central serotonin2B receptor (5-HT2BR) is currently considered as an interesting pharmacological target for improved treatment of drug addiction. In the present study, we assessed the effect of two selective 5-HT2BR antagonists, RS 127445 and LY 266097, on cocaine-induced hyperlocomotion and dopamine (DA) outflow in the nucleus accumbens (NAc) and the dorsal striatum of freely moving rats. The peripheral administration of RS 127445 (0.16 mg/kg, i.p.) or LY 266097 (0.63 mg/kg, i.p.) significantly reduced basal DA outflow in the NAc shell, but had no effect on cocaine (10 mg/kg, i.p.)-induced DA outflow in this brain region. Also, RS 127445 failed to modify both basal and cocaine-induced DA outflow in the NAc core and the dorsal striatum. Conversely, both 5-HT2BR antagonists reduced cocaine-induced hyperlocomotion. Furthermore, RS 127445 as well as the DA-R antagonist haloperidol (0.1 mg/kg, i.p.) reduced significantly the late-onset hyperlocomotion induced by the DA-R agonist quinpirole (0.5 mg/kg, s.c.). Altogether, these results demonstrate that 5-HT2BR blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical DA outflow. This interaction takes place downstream to DA neurons and could involve an action at the level of dorsostriatal and/or NAc DA transmission, in keeping with the importance of these brain regions in the behavioural responses of cocaine. Overall, this study affords additional knowledge into the regulatory control exerted by the 5-HT2BR on ascending DA pathways, and provides additional support to the proposed role of 5-HT2BRs as a new pharmacological target in drug addiction.

  19. Attack helicopter (AH-1T) cockpit systems integration

    NASA Technical Reports Server (NTRS)

    Graf, V. A.

    1984-01-01

    This discussion summarizes the effort conducted by the BHTI Human Factors and Cockpit Arrangement group for a study and design of the integration of a cockpit control system for the AH 1T (TOW). The resulting design is a culmination of studies that were conducted using the existing configuration as a baseline and complementing it with new equipment and subsystems that fulfill the attack helicopter requirements for the foreseeable future. Of primary concern was the requirement to add a missile control system, with secondary considerations for improved NOE and night operations. In addition, growth capabilities for improved target acquisition, weapons delivery, and precise navigation was considered. Along with the addition of new equipment, the aircraft was assumed to have a central multiplex data bus system for information transfer throughout the aircraft and its subsystems.

  20. Human Infection with Highly Pathogenic A(H7N7) Avian Influenza Virus, Italy, 2013

    PubMed Central

    Rossini, Giada; Facchini, Marzia; Vaccari, Gabriele; Di Trani, Livia; Di Martino, Angela; Gaibani, Paolo; Vocale, Caterina; Cattoli, Giovanni; Bennett, Michael; McCauley, John W.; Rezza, Giovanni; Moro, Maria Luisa; Rangoni, Roberto; Finarelli, Alba Carola; Landini, Maria Paola; Castrucci, Maria Rita; Donatelli, Isabella

    2014-01-01

    During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms. PMID:25271444

  1. Pityriazepin and other potent AhR ligands isolated from Malassezia furfur yeast

    PubMed Central

    Mexia, Nikitia; Gaitanis, George; Velegraki, Aristea; Soshilov, Anatoly; Denison, Michael S.; Magiatis, Prokopios

    2015-01-01

    Malassezia furfur yeast strains isolated from diseased human skin preferentially biosynthesize indole alkaloids which can be detected in human skin and are highly potent activators of the aryl hydrocarbon receptor (AhR) and AhR-dependent gene expression. Chemical analysis of an EtOAc extract of a M. furfur strain obtained from diseased human skin and grown on L-tryptophan agar revealed several known AhR active tryptophan metabolites along with a previously unidentified compound, pityriazepin. While its structure resembled that of the known alkaloid pityriacitrin, the comprised pyridine ring had been transformed into an azepinone. The indoloazepinone scaffold of pityriazepin is extremely rare in nature and has only been reported once previously. Pityriazepin, like the other isolated compounds, was found to be a potent activator of the AhR-dependent reporter gene assays in recombinant cell lines derived from four different species, although significant species differences in relative potency was observed. The ability of pityriazepin to competitively bind to the AhR and directly stimulate AhR DNA binding classified it as a new naturally-occurring potent AhR agonist. Malassezia furfur produces an expanded collection of extremely potent naturally occurring AhR agonists, which produce their biological effects in a species-specific manner.1 PMID:25721496

  2. A historical perspective of influenza A(H1N2) virus.

    PubMed

    Komadina, Naomi; McVernon, Jodie; Hall, Robert; Leder, Karin

    2014-01-01

    The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H3N2 subtype was isolated from humans, and by 2012, the number of persons infected began to increase with limited person-to-person transmission. During 2012 in the United States, an A(H1N2)v virus was transmitted to humans from swine. During the same year, Australia recorded its first H1N2 subtype infection among swine. The A(H3N2)v and A(H1N2)v viruses contained the matrix protein from the A(H1N1)pdm09 virus, raising the possibility of increased transmissibility among humans and underscoring the potential for influenza pandemics of novel swine-origin viruses. We report on the differing histories of A(H1N2) viruses among humans and animals.

  3. A Modified Delphi Study to Define "Ah Ha" Moments in Education Settings

    ERIC Educational Resources Information Center

    Pilcher, Jobeth

    2015-01-01

    Ah ha moments are often mentioned in education literature. These moments are suggested to be a powerful aspect of learning, yet limited research is present regarding this topic. Ah ha learning moments have also not been defined in the education literature, resulting in the likelihood that each educator and learner may have differing definitions.…

  4. A Lagrangian view of ozone production tendency in North American outflow in summers 2009 and 2010

    NASA Astrophysics Data System (ADS)

    Zhang, Bo; Owen, R. Chris; Perlinger, Judith; Kumar, Aditya; Wu, Shiliang; Martin, Maria Val; Kramer, Louisa; Helmig, Detlev

    2013-04-01

    The Pico Mountain Observatory, located at 2,225 ma.s.l. in the Azores Islands, was established in 2001 to observe long-range transport from North America to the central North Atlantic. In previous research conducted at the Observatory, ozone enhancements (> 55 ppbv) were observed in North American outflows containing anthropogenic and biomass burning emissions, and efficient ozone production in these outflows was postulated. One of the major objectives of BORTAS is to better understand chemical composition and evolution during transport of biomass burning outflows. A key to the study of pollution plumes at a ground-based station is identification of emission type and source region(s). Transport pathways of individual plumes are also thought to be critical to plume aging. In this study, by analyzing observations of atmospheric tracer gases at Pico and FLEXPART simulation results, we were able to identify transport events induced by anthropogenic or biomass burning emissions during summers 2009 and 2010. In order to assess ozone production tendency during these long-range transport events, the convolved or "folded" retroplume technique developed by Owen and Honrath (2009) was applied to combine upwind FLEXPART transport pathways with GEOS-Chem chemical fields, providing a semi-lagrangian view of physical properties and production/loss of ozone in polluted North American outflows. Two anthropogenic events from North America were selected for detailed analysis because anthropogenic emissions were considered to be more predictable and consistent over time. Ozone enhancement was observed in both plumes, but due to differing transport mechanisms, ozone production tendency was found to be different between the two. In the first case, ozone production was found during the last two days of transport, when the pollution plume subsided from the free troposphere to the altitude of Pico station in the high pressure system centered over the Azores region at the time. Increase of

  5. Estimation of cold plasma outflow during geomagnetic storms

    NASA Astrophysics Data System (ADS)

    Haaland, S.; Eriksson, A.; André, M.; Maes, L.; Baddeley, L.; Barakat, A.; Chappell, R.; Eccles, V.; Johnsen, C.; Lybekk, B.; Li, K.; Pedersen, A.; Schunk, R.; Welling, D.

    2015-12-01

    Low-energy ions of ionospheric origin constitute a significant contributor to the magnetospheric plasma population. Measuring cold ions is difficult though. Observations have to be done at sufficiently high altitudes and typically in regions of space where spacecraft attain a positive charge due to solar illumination. Cold ions are therefore shielded from the satellite particle detectors. Furthermore, spacecraft can only cover key regions of ion outflow during segments of their orbit, so additional complications arise if continuous longtime observations, such as during a geomagnetic storm, are needed. In this paper we suggest a new approach, based on a combination of synoptic observations and a novel technique to estimate the flux and total outflow during the various phases of geomagnetic storms. Our results indicate large variations in both outflow rates and transport throughout the storm. Prior to the storm main phase, outflow rates are moderate, and the cold ions are mainly emanating from moderately sized polar cap regions. Throughout the main phase of the storm, outflow rates increase and the polar cap source regions expand. Furthermore, faster transport, resulting from enhanced convection, leads to a much larger supply of cold ions to the near-Earth region during geomagnetic storms.

  6. Estimation of cold plasma outflow during geomagnetic storms

    NASA Astrophysics Data System (ADS)

    Haaland, S.; Eriksson, A. I.; Andre, M.; Maes, L.; Baddeley, L. J.; Barakat, A. R.; Chappell, C. R.; Eccles, V.; Johnsen, C.; Lybekk, B.; Li, K.; Pedersen, A.; Schunk, R. W.; Welling, D. T.

    2015-12-01

    Low energy ions of ionospheric origin provide a significant contributon to the magnetospheric plasmapopulation. Measuring cold ions is difficult though. Observations have to be done at sufficiently high altitudes and typically in regions of space where spacecraft attain a positive charge due to solar illumination. Cold ions are therefore shielded from the satellite particle detectors. Furthermore, spacecraft can only cover key regions of ion outflow during segments of their orbit, so additional complications arise arise if continuous longtime observations such as the during a geomagnetic storms are needed. In this paper we suggest a new approach, based on a combination of synoptic observations and a novel technique to estimate the flux and total outflow during the various phases of geomagnetic storms. Our results indicate large variations in both outflow rates and transport throughout the storm. Prior to the storm main phase, outflow rates are moderate, and the cold ions are mainly emanating from moderately sized polar cap regions. Throughout the main phase of the storm, outflow rates increase and the polar cap source regions expand. Furthermore, faster transport, resulting from enhanced convection, leads to a much larger supply of cold ions to the near Earth region during gemagnetic storms.

  7. Studying AGN Feedback with Galactic Outflows in Luminous Obscured Quasar

    NASA Astrophysics Data System (ADS)

    Sun, Ai-Lei

    2016-01-01

    Feedback from Active galactic nuclei (AGN) has been proposed as an important quenching mechanism to suppress star formation in massive galaxies. We investigate the most direct form of AGN feedback - galactic outflows - in the most luminous obscured AGN (L>10^45 erg/s) from the SDSS sample in the nearby universe (z<0.2). Using ALMA and Magellan observations to target molecular and ionized outflows, we find that luminous AGN can impact the dynamics and phase of the galactic medium, and confirm the complex multi-phase and multi-scaled nature of the feedback phenomenon. In particular, we found that most of these luminous AGN hosts ionized outflows. The outflow size, velocity, and energetics correlate with the AGN luminosity, and can be very extended (r > 10 kpc) and fast (v > 1000 km/s) for the most luminous ones. I end with presenting a new technique to find extended ionized outflows using broadband imaging surveys, and to characterize their occurrence rate, morphology, size distribution, and their dependence on the AGN luminosity. This technique will open a new window for feedback studies in the era of large-scale optical imaging surveys, e.g., HSC and then LSST.

  8. Giant Molecular Outflows Powered by Protostars in L1448

    NASA Astrophysics Data System (ADS)

    Barsony, Mary; Wolf-Chase, Grace A.; O'Linger, Joann

    1999-10-01

    We present sensitive (T*R somewhat equal to 0.1K), large-scale (47' x 7'--corresponding to 4 pc x 6 pc at the source) maps of the CO J = 1 to 0 emission of the L1448 dark cloud at 55" resolution. The maps were acquired using the On-The-Fly (OTF) capability of the NRAO's 12-meter telescope. Careful comparison of the spatial and velocity distribution of the high-velocity CO with previously published optical and near-infrared images and spectra has led to the identification of four distinct, parsec-scale molecular outflows from our maps. These CO flows are powered by four Class 0 protostars: L1448C, L1448N(A), L1448N(B), and L1448 IRS2 and end at the cloud's boundaries. The famous, well-collimated, high-velocity molecular outflow powered by L1448C can now be traced to distances an order of magnitude greater than previously. We present strong evidence for interactions between all four outflows on scales over a parsec from the driving sources. The magnitude of the combined flow momenta, as well as the combined kinetic energy of the flows, are sufficient to disperse the 50 MSun ammonia core in which the protostars are currently forming. It remains to be shown whether the combined directions of the outflow momenta, and the efficiency of momentum transfer from outflow to ambient material, are sufficient for dispersal of the L1448 molecular cloud.

  9. The Molecular Gas Outflow of NGC 1068 Imaged by ALMA

    NASA Astrophysics Data System (ADS)

    García-Burillo, S.

    2015-12-01

    We have used the ALMA array to map the emission of a set of dense molecular gas tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) in the central r˜2 kpc of the Seyfert 2 galaxy NGC 1068 with spatial resolutions ˜0.3″-0.5″ (˜20-35 pc). The sensitivity and spatial resolution of ALMA give a detailed view of the distribution and kinematics of the dense molecular gas. The gas kinematics from r˜50 pc out to r˜400 pc reveal a massive outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. The outflow rate estimated in the CND, M/dt˜63+21-37 M⊙ yr-1, is an order of magnitude higher than the star formation rate at these radii. The molecular outflow could quench star formation in the inner r˜400 pc of the galaxy on short timescales of ≤1 Myr and regulate gas accretion in the CND.

  10. Identification of Influenza A/H7N9 Virus Infection-Related Human Genes Based on Shortest Paths in a Virus-Human Protein Interaction Network

    PubMed Central

    Huang, Tao; Cai, Yu-Dong

    2014-01-01

    The recently emerging Influenza A/H7N9 virus is reported to be able to infect humans and cause mortality. However, viral and host factors associated with the infection are poorly understood. It is suggested by the “guilt by association” rule that interacting proteins share the same or similar functions and hence may be involved in the same pathway. In this study, we developed a computational method to identify Influenza A/H7N9 virus infection-related human genes based on this rule from the shortest paths in a virus-human protein interaction network. Finally, we screened out the most significant 20 human genes, which could be the potential infection related genes, providing guidelines for further experimental validation. Analysis of the 20 genes showed that they were enriched in protein binding, saccharide or polysaccharide metabolism related pathways and oxidative phosphorylation pathways. We also compared the results with those from human rhinovirus (HRV) and respiratory syncytial virus (RSV) by the same method. It was indicated that saccharide or polysaccharide metabolism related pathways might be especially associated with the H7N9 infection. These results could shed some light on the understanding of the virus infection mechanism, providing basis for future experimental biology studies and for the development of effective strategies for H7N9 clinical therapies. PMID:24955349

  11. Observations of a curving molecular outflow from V380Ori-NE: further support for prompt entrainment in protostellar outflows

    NASA Astrophysics Data System (ADS)

    Davis, C. J.; Dent, W. R. F.; Matthews, H. E.; Coulson, I. M.; McCaughrean, M. J.

    2000-11-01

    CO J=3-2 and 4-3 observations of V380Ori-NE reveal a highly collimated bipolar molecular outflow associated with a jet traced here in H2 1-0 S(1) line emission. The source of the flow is also detected at 450 and 850μm with SCUBA. The combined CO and near-IR observations offer compelling support for the prompt entrainment model of jet-driven molecular outflows. Not only are the H2 shock fronts spatially coincident with peaks in the CO outflow lobes, but the slope of the mass-velocity distribution in the flow, measured here at intervals along both flow lobes, also clearly decreases just behind the advancing shock fronts (and towards the ends of the flow lobes), as one would expect if the high-to-low velocity mass fraction was enhanced by the entraining shocks. We also find that both lobes of the CO outflow clearly deviate, by some 20°, from the H2 jet direction near the source. Both lobes may be being deflected at the locations of the observed H2 shock fronts, where they impact dense, ambient material. Alternatively, the almost point-symmetric CO flow pattern could be caused by precession at the source. The submillimetre (submm) data reveal the source of the outflow, V380Ori-NE. The 450- and 850-μm maps show an elongated peak superimposed on to an extensive pedestal of weaker emission. The major axis of the source is oriented parallel with the inner flow axis. Indeed, weak 850-μm emission is detected along much of the bipolar outflow, particularly in the southern lobe and towards the southernmost CO intensity peak. The submm `continuum' data therefore probably trace warm dust and CO associated with the outflow. These data also confirm the status of V380Ori-NE as a Class I protostar. Overall, the orientation, simplicity and symmetry of this outflow, combined with the remarkable strength of the high-velocity line-wing emission in comparison to the ambient emission, make this system a perfect laboratory for future detailed studies of bipolar molecular outflows and

  12. Bipolar Molecular Outflows from High-Mass Protostars

    NASA Astrophysics Data System (ADS)

    Su, Yu-Nung; Zhang, Qizhou; Lim, Jeremy

    2004-03-01

    We report observations of the bipolar molecular outflows associated with the luminous (~2×104 Lsolar) far-IR sources IRAS 21519+5613 and IRAS 22506+5944, as well the dust and molecular gas condensations on which these outflows appear to be centered. The observations were made in 12CO, 13CO, C18O, and continuum at 3 mm with the BIMA array and in 12CO and 13CO with the NRAO 12 m telescope to recover extended emission filtered out by the interferometric array. We find that the outflow associated with each IRAS source shows a clear bipolar morphology in 12CO, with properties (i.e., total mass of order 10-100 Msolar, mass-outflow rate >~10-3 Msolar, dynamical timescale 104-105 yr, and energetics) comparable with those of other massive outflows associated with luminous young stellar objects. Each outflow appears to be centered on a dust and gas condensation with a mass of 200-300 Msolar, likely marking the location of the driving source. The outflow lobes of both sources are fully resolved along their major but not minor axes, and they have collimation factors that may be comparable with young low-mass stars. The mass-velocity diagrams of both outflows change in slope at a velocity of ~10 km s-1, suggesting that the high-velocity component (HVC) may drive the low-velocity component (LVC). Although the HVC of IRAS 21519+5613 shows evidence for deceleration, no such signature is seen in the HVC of IRAS 22506+5944. Neither HVC has a momentum supply rate sufficient to drive their corresponding LVCs, although it is possible that the HVC is more highly excited and hence its thrust underestimated. Like for other molecular outflows the primary driving agent cannot be ionized gas, leaving atomic gas as the other remaining candidate. Neither IRAS 21519+5613 nor IRAS 22506+5944 exhibits detectable free-free emission, which together with the observed properties of their molecular outflows and surrounding condensations make them credible candidates for high-mass protostars. The mass

  13. Triggered star formation: Rotation, magnetic fields and outflows

    NASA Astrophysics Data System (ADS)

    Frank, A.; Li, S.; Blackman, E. G.

    2015-12-01

    Star formation can be triggered by compression from wind or supernova driven shock waves that sweep over molecular clouds. In a previous work we used Adaptive Mesh Refinement (AMR) simulation methods, including sink particles, to simulate the full collapse of a stable Bonnor-Ebert sphere subjected to a passing shock. We tracked the flow of cloud material after a star (a sink particle) had formed. For rotating clouds we observed the formation of disks which then interact with the post-shock flow. In this paper we take the next step forward in complexity, presenting first results of simulations that include a magnetized cloud. Our results show that after a disk is formed a collimated magneto-centrifugal outflow is launched. The outflow is bipolar but asymmetric, due to interactions with the shocked flow. We explore the influence of the outflows on the post-triggering collapse dynamics.

  14. Plasma Outflows: Known Knowns, Known Unknowns, and The Unknown

    NASA Technical Reports Server (NTRS)

    Moore, T. E.

    2012-01-01

    A brief summary is given of i) what we know from observing ionospheric outflows and ii) how outflow parameterizations are being used in global simulations to evaluate their effects on magnetospheric dynamics. Then, a list of unanswered questions and issues to be resolved is given, followed by a description of the known future mission plans expressed in the Heliophysics Roadmap, such as Origin of Near-Earth Plasmas (ONEP), and Ion-Neutral Coupling in the Atmosphere (INCA). Finally, a set of requirements for definitive plasma outflow observations are identified, along with possible methods for fulfilling them in future missions. Since results of the current Heliophysics Decadal Survey are expected soon, it is hoped that future plans can be summarized and discussed without speculation at the GEM 2012 meeting.

  15. Precursor systems analyses of automated highway systems. Activity area K AHS roadway operational analysis. Final report, September 1993-November 1994

    SciTech Connect

    Schulze, R.; Roper, D.; Tsao, J.; Michael, B.

    1995-05-01

    This study considers the roadway operational requirements of an automated highway system (AHS) in light of corresponding operational requirements for existing conventional highways with traffic operations centers (TOCs). Contrasts and similarities between TOC and AHS operations are identified. Maintenance operations and activities are the focus of the study. Similarities and contrasts between AHS and conventional highways are considered, analyzed, and discussed to raise issues risks. Urban/rural, passenger/heavy vehicle, and representative system configuration differences are covered insofar as there are significant differences among these categories of possible AHS operations. Maintenance needs and incident response requirements as they would impact as AHS operating agency are qualitatively analyzed. Two possible staged deployment scenarios for AHS are presented. The fault tolerance of the AHS is assessed. Results of interviews with personnel in charge of several existing TOCs have been summarized. The role of the driver in an AHS is discussed.

  16. Formation of Hydrocarbons in the Outflows from Red Giants

    NASA Technical Reports Server (NTRS)

    Roberge, Wayne; Kress, Monika; Tielens, Alexander G.

    1995-01-01

    The formation of hydrocarbons in the oxygen-rich outflows from red giants was studied. The existence of organic molecules in such outflows has been known for several years; however, their surprisingly high abundances has been a mystery since all of the carbon had been thought to be irretrievably locked up in CO, the most strongly bound molecule. CO is the first molecule to form from the atoms present in the star's extended atmosphere, and as strong stellar winds drive a cooling outflow, dust grains condense out. In oxygen-rich outflows, the dust is thought to be composed mainly of silicates and other metal oxides. Perhaps the noble metals can condense out in metallic form, in particular the relatively abundant transition metals iron and nickel. We proposed that perhaps the carbon reservoir held as CO can be accessed through a catalytic process involving the chemisorption of CO and H2 onto grains rich in metallic iron. CO and H2 are the two most abundant molecules in circumstellar outflows, and they both are known to dissociate on transition metal surfaces at elevated temperatures, freeing carbon to form organic molecules such as methane. We believe methane is a precursor molecule to the organics observed in oxygen-rich red giants. We have developed a nonequilibrium numerical model of a surface chemical (catalytic) process. Based on this model, we believe that methane can be formed under the conditions present in circumstellar outflows. Although the methane formation rates are exceptionally low under these conditions, over dynamical timescales, a significant amount of CO can be converted to methane and driven further out in the envelope, explaining the presence of organics there.

  17. A cluster of outflows in the Vulpecula Rift

    NASA Astrophysics Data System (ADS)

    Mottram, J. C.; Brunt, C. M.

    2012-02-01

    We present 12CO, 13CO and C18O (J=3-2) observations of a new cluster of outflows in the Vulpecula Rift with HARP on the James Clerk Maxwell Telescope (JCMT). The mass associated with the outflows, measured using the 12CO HARP observations and assuming a distance to the region of 2.3 kpc, is 129 M⊙, while the mass associated with the dense gas from C18O observations is 458 M⊙ and the associated sub-millimeter (sub-mm) core has a mass of 327 ± 112 M⊙ independently determined from Bolocam 1.1-mm data. The outflow-to-core mass ratio is therefore ˜0.4, making this region one of the most efficient observed thus far with more than an order of magnitude more mass in the outflow than would be expected based on previous results. The kinetic energy associated with the flows, 94 × 1045 erg, is enough to drive the turbulence in the local clump, and potentially unbind the local region altogether. The detection of SiO (J=8-7) emission towards the outflows indicates that the flow is still active, and not simply a fossil flow. We also model the spectral energy distributions (SEDs) of the four young stellar objects (YSOs) associated with the molecular material, finding them all to be of mid to early B spectral type. The energetic nature of the outflows and significant reservoir of cold dust detected in the sub-mm suggest that these intermediate mass YSOs will continue to accrete and become massive, rather than reach the main sequence at their current mass.

  18. High resolution imaging of the outflow channels on Mars

    NASA Astrophysics Data System (ADS)

    Davatzes, A. K.; Gulick, V. C.

    2008-12-01

    We report observations of the outflow channels on Mars from HiRISE images in MRO's first Martian year. Several hundred images of the outflow channels on Mars have been collected to date from HiRISE, as well as coordinated images with CTX and CRISM. Depositional features, such as slackwater deposits and small bedforms that are expected to be visible at the resolution of HiRISE have not yet been observed, largely due to post-fluvial modification of the channels. Many of the channels have been subsequently covered by a thin layer of lava, ash, dust, or lineated valley fill. Although altered slightly by later aeolian modification, Ares Valles and Kasei Valles preserve much of the original fluvial erosional forms, particularly cataracts and longitudinal grooves that can be used to infer the mechanics of the flow. Cataracts, steep knickpoints in the large outflow channels, were once large waterfalls on the Martian surface. These have been observed in all of the larger outflow systems, including Kasai, Athabasca, Mangala, and Reull Valles. High resolution imaging shows that all of the cataract systems have multiple generations of erosion, with smaller subchannels within the cataract system. Based on the length of the recession and the morphological evidence most of the large channels experienced multiple flooding events or pulses. The tectonically sourced outflow channels, such as Athabasca and Mangala Valles, show sourcing at regions of complex fault geometries, specifically at fault relays. In terrestrial systems, relays tend to be regions of concentrated stress that can produce dilation manifested as high joint density, as well as point sources for hydrothermal outflow on Earth. Athabasca and Mangala Valles, sourced proximal to large volcanic centers, may have been regions of major hydrothermal activity in the past.

  19. Fast outflows and star formation quenching in quasar host galaxies

    NASA Astrophysics Data System (ADS)

    Carniani, S.; Marconi, A.; Maiolino, R.; Balmaverde, B.; Brusa, M.; Cano-Díaz, M.; Cicone, C.; Comastri, A.; Cresci, G.; Fiore, F.; Feruglio, C.; La Franca, F.; Mainieri, V.; Mannucci, F.; Nagao, T.; Netzer, H.; Piconcelli, E.; Risaliti, G.; Schneider, R.; Shemmer, O.

    2016-06-01

    Negative feedback from active galactic nuclei (AGN) is considered a key mechanism in shaping galaxy evolution. Fast, extended outflows are frequently detected in the AGN host galaxies at all redshifts and luminosities, both in ionised and molecular gas. However, these outflows are only potentially able to quench star formation, and we are still lacking decisive evidence of negative feedback in action. Here we present observations obtained with the Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) H- and K-band integral-field of two quasars at z ~ 2.4 that are characterised by fast, extended outflows detected through the [Oiii]λ5007 line. The high signal-to-noise ratio of our observations allows us to identify faint narrow (FWHM< 500 km s-1) and spatially extended components in [Oiii]λ5007 and Hα emission associated with star formation in the host galaxy. This star formation powered emission is spatially anti-correlated with the fast outflows. The ionised outflows therefore appear to be able to suppress star formation in the region where the outflow is expanding. However, the detection of narrow spatially extended Hα emission indicates star formation rates of at least ~50-90 M⊙ yr-1, suggesting either that AGN feedback does not affect the whole galaxy or that many feedback episodes are required before star formation is completely quenched. On the other hand, the narrow Hα emission extending along the edges of the outflow cone may also lead also to a positive feedback interpretation. Our results highlight the possible double role of galaxy-wide outflows in host galaxy evolution. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, P.ID: 086.B-0579(A) and 091.A-0261(A).The reduced data cubes are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A28

  20. River Outflow of the Conterminous United States, 1939-1988.

    NASA Astrophysics Data System (ADS)

    Guetter, Alexandre K.; Georgakakos, Konstantine P.

    1993-10-01

    A record of 50 years of daily outflows through the boundaries of the continental United States has been assembled based on observations recorded by U.S. Geological Survey streamflow stations. Only stations with continuous records from 1939 through 1988 were included. These stations (197 total) are near the outlets of rivers located at the vicinity of the Canadian, Mexican, Atlantic (including the Gulf of Mexico), and Pacific borders of the continental United States. The drainage area of the selected stations covers 77% of the conterminous United States, whereas the existing network of gauging stations covers 83% of the conterminous U.S. area. Station daily data were aggregated over the entire boundary of the United States and were integrated in monthly and annual totals. The 50-year average annual streamflow divergence normalized by the aggregated drainage area is 210.2 mm yr1, reaching a peak in April with 27.3 mm month1 and a minimum in September with 8.7 mm month1. The Mississippi-Missouri Basin comprises 50% of the gauged area and dominates the absolute value of the outflow discharge. Spectral analysis of the monthly outflow anomalies shows an 11-year dominant cycle. The 1939-1988 period contains four notable droughts. Two droughts are partially registered in the limits of the records characterized by the negative anomalies extending from 1939 to 1941 and by the 1987-1988 anomalies for the late 1980s drought. The middle 1950s and early 1960s droughts are fully included in the dataset. Periods of high outflows were registered in the middle 1940s, early 1970s, and early 1980s. Analysis of the spatial coherence of the annual anomalies shows large-scale features, whereas analysis of the monthly anomalies yields the frequency and persistence patterns of floods and droughts. An estimate of the climatological land-surface water budget for the continental United States was done based on recorded precipitation, panevaporation, and outflow. Eigenvector analysis of the

  1. Collapse of Rotating Magnetized Molecular Cloud Cores and Mass Outflows

    NASA Astrophysics Data System (ADS)

    Tomisaka, Kohji

    2002-08-01

    The collapse of rotating magnetized molecular cloud cores is studied with axisymmetric magnetohydrodynamic (MHD) simulations. Because of the change of the equation of state of the interstellar gas, molecular cloud cores experience several phases during the collapse. In the earliest isothermal runaway collapse (n<~1010 H2 cm-3), a pseudodisk is formed, and it continues to contract until an opaque core is formed at the center. In this disk, a number of MHD fast and slow shock pairs appear whose wave fronts are parallel to the disk. We assume that the interstellar gas obeys a polytropic equation of state with the exponent of Γ>1 above the critical density at which the core becomes optically thick against the thermal radiation from dusts ncr~1010 cm-3. After the equation of state becomes hard, an adiabatic quasi-static core forms at the center (the first core), which is separated from the isothermal contracting pseudodisk by the accretion shock front facing radially outward. By the effect of the magnetic tension, the angular momentum is transferred from the disk midplane to the surface. The gas with an excess angular momentum near the surface is finally ejected, which explains the molecular bipolar outflow. Two types of outflows are found. When the poloidal magnetic field is strong (its energy is comparable to the thermal one), a U-shaped outflow is formed, in which gas is mainly outflowing through a region whose shape looks like a capital letter U at a finite distance from the rotation axis. The gas is accelerated by the centrifugal force and the magnetic pressure gradient of the toroidal component. The other is a turbulent outflow in which magnetic field lines and velocity fields seem to be randomly oriented. In this case, globally the gas moves out almost perpendicularly from the disk, and the outflow looks like a capital letter I. In this case, although the gas is launched by the centrifugal force, the magnetic force working along the poloidal field lines plays an

  2. Outflow channel sources, reactivation, and chaos formation, Xanthe Terra, Mars

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Sasaki, S.; Kuzmin, R.O.; Dohm, J.M.; Tanaka, K.L.; Miyamoto, H.; Kurita, K.; Komatsu, G.; Fairen, A.G.; Ferris, J.C.

    2005-01-01

    The undulating, warped, and densely fractured surfaces of highland regions east of Valles Marineris (located north of the eastern Aureum Chaos, east of the Hydraotes Chaos, and south of the Hydaspis Chaos) resulted from extensional surface warping related to ground subsidence, caused when pressurized water confined in subterranean caverns was released to the surface. Water emanations formed crater lakes and resulted in channeling episodes involved in the excavation of Ares, Tiu, and Simud Valles of the eastern part of the circum-Chryse outflow channel system. Progressive surface subsidence and associated reduction of the subsurface cavernous volume, and/or episodes of magmatic-driven activity, led to increases of the hydrostatic pressure, resulting in reactivation of both catastrophic and non-catastrophic outflow activity. Ancient cratered highland and basin materials that underwent large-scale subsidence grade into densely fractured terrains. Collapse of rock materials in these regions resulted in the formation of chaotic terrains, which occur in and near the headwaters of the eastern circum-Chryse outflow channels. The deepest chaotic terrain in the Hydaspis Chaos region resulted from the collapse of pre-existing outflow channel floors. The release of volatiles and related collapse may have included water emanations not necessarily linked to catastrophic outflow. Basal warming related to dike intrusions, thermokarst activity involving wet sediments and/or dissected ice-enriched country rock, permafrost exposed to the atmosphere by extensional tectonism and channel incision, and/or the injection of water into porous floor material, may have enhanced outflow channel floor instability and subsequent collapse. In addition to the possible genetic linkage to outflow channel development dating back to at least the Late Noachian, clear disruption of impact craters with pristine ejecta blankets and rims, as well as preservation of fine tectonic fabrics, suggest that

  3. Mechanisms for pressurized groundwater outflow channels, implications for Mars

    NASA Astrophysics Data System (ADS)

    Marra, Wouter A.; Kleinhans, Maarten G.; Hauber, Ernst; McLelland, Stuart J.; Murphy, Brendan J.; Parsons, Daniel R.; Conway, Susan J.

    2014-05-01

    Various valleys on Mars show evidence for extensive fluvial activity in the past. The largest valleys on Mars are several tens to hundreds of kilometers wide and are thought to have originated from outflow of pressurized groundwater. However, exact mechanisms of these processes are lacking, which hampers a quantitative interpretation of some of the most impressive morphological features on Mars. Using flume experiments, we studied a range of possible pressurized groundwater outflow mechanisms including artesian seepage, enhanced seepage through fissures and the eruption of a pressurized groundwater reservoir. These experiments focused on the morphological development of such systems. We also analyze the scalability of the laboratory analogues to real-word systems and we study the outflow-channel areas in Lunae Planum and Xanthe Terra north of Valles Marineris. In the experiments, we found that low water injection pressures led to the formation of surface lakes, intermediate pressures led to the formation of subsurface fissures, and high pressure led to the buildup of a pressurized subsurface lake that erupted to the surface. Each of these systems resulted in catastrophic release of water greater than the groundwater discharge, from accumulation in a lake, enhanced seepage through fissures or both. In all experiments, an outflow channel formed, but we observed other morphologies as well that are unique to the mechanism of release. Fissure seepage created small holes and in the case of a subsurface lake eruption, large depressions and fractures were formed. In all cases, the sudden release of water resulted in the deposition of sedimentary lobes due to infiltration of water flowing over downstream areas that were still dry. This mechanism is absent in in the case of slow groundwater outflow. Our study of the surface of Mars reveals a range of morphological features that were not associated with pressurized groundwater outflow before. These features include

  4. THE ANATOMY OF THE YOUNG PROTOSTELLAR OUTFLOW HH 211

    SciTech Connect

    Tappe, A.; Forbrich, J.; Lada, C. J.; Martin, S.; Yuan, Y.

    2012-05-20

    We present Spitzer Space Telescope 5-36 {mu}m mapping observations toward the southeastern lobe of the young protostellar outflow HH 211. The southeastern terminal shock of the outflow shows a rich mid-infrared spectrum including molecular emission lines from OH, H{sub 2}O, HCO{sup +}, CO{sub 2}, H{sub 2}, and HD. The spectrum also shows a rising infrared continuum toward 5 {mu}m, which we interpret as unresolved emission lines from highly excited rotational levels of the CO v = 1-0 fundamental band. This interpretation is supported by a strong excess flux observed in the Spitzer/IRAC 4-5 {mu}m channel 2 image compared to the other IRAC channels. The extremely high critical densities of the CO v = 1-0 ro-vibrational lines and a comparison to H{sub 2} and CO excitation models suggest jet densities larger than 10{sup 6} cm{sup -3} in the terminal shock. We also observed the southeastern terminal outflow shock with the Submillimeter Array and detected pure rotational emission from CO 2-1, HCO{sup +} 3-2, and HCN 3-2. The rotationally excited CO traces the collimated outflow backbone as well as the terminal shock. HCN traces individual dense knots along the outflow and in the terminal shock, whereas HCO{sup +} solely appears in the terminal shock. The unique combination of our mid-infrared and submillimeter observations with previously published near-infrared observations allow us to study the interaction of one of the youngest known protostellar outflows with its surrounding molecular cloud. Our results help us to understand the nature of some of the so-called green fuzzies (Extended Green Objects), and elucidate the physical conditions that cause high OH excitation and affect the chemical OH/H{sub 2}O balance in protostellar outflows and young stellar objects. In an appendix to this paper, we summarize our Spitzer follow-up survey of protostellar outflow shocks to find further examples of highly excited OH occurring together with H{sub 2}O and H{sub 2}.

  5. Aqueous Humor Outflow Structure and Function Imaging At the Bench and Bedside: A Review

    PubMed Central

    Huang, Alex S.; Mohindroo, Chirayu; Weinreb, Robert N.

    2016-01-01

    Anterior segment glaucoma clinical care and research has recently gained new focus because of novel imaging modalities and the advent of angle-based surgical treatments. Traditional investigation drawn to the trabecular meshwork now emphasizes the entire conventional aqueous humor outflow (AHO) pathway from the anterior chamber to the episcleral vein. AHO investigation can be divided into structural and functional assessments using different methods. The historical basis for studying the anterior segment of the eye and AHO in glaucoma is discussed. Structural studies of AHO are reviewed and include traditional pathological approaches to modern tools such as multi-model two-photon microscopy and optical coherence tomography. Functional assessment focuses on visualizing AHO itself through a variety of non-real-time and real-time techniques such as aqueous angiography. Implications of distal outflow resistance and segmental AHO are discussed with an emphasis on melding bench-side research to viable clinical applications. Through the development of an improved structure: function relationship for AHO in the anterior segment of the normal and diseased eye, a better understanding of the eye with improved therapeutics may be developed. PMID:27790380

  6. Extreme luminosities in ejecta produced by intermittent outflows around rotating black holes

    NASA Astrophysics Data System (ADS)

    van Putten, Maurice H. P. M.

    2015-02-01

    Extreme sources in the Transient Universe show evidence of relativistic outflows from intermittent inner engines, such as cosmological gamma-ray bursts (GRBs). They probably derive from rotating back holes interacting with surrounding matter. We show that these interactions are enhanced inversely proportional to the duty cycle in advection of magnetic flux, as may apply at high accretion rates. We demonstrate the morphology and ballistic propagation of relativistic ejecta from burst outflows by numerical simulations in relativistic magnetohydrodynamics. Applied to stellar mass black holes in core-collapse of massive stars, it provides a robust explosion mechanism as a function of total energy output. At breakout, these ejecta may produce a low-luminosity GRB. A long GRB may ensue from an additional ultrarelativistic baryon-poor inner jet from a sufficiently long-lived intermittent inner engine. The simulations demonstrate a complex geometry in mergers of successive ejecta, whose mixing and shocks provide a pathway to broad-band high-energy emission from magnetic reconnection and shocks.

  7. The 50 Ah NiH2 CPV qualification tests

    NASA Technical Reports Server (NTRS)

    Garner, J. C.; Barnes, Wilbert L.; Hickman, Gary L.

    1995-01-01

    In 1992, the Naval Research Laboratory (NRL) started a program to qualify a large diameter common pressure vessel (CPV) nickel-hydrogen (NiH2) batteries for use on future Navy/NRL spacecraft electrical power subsystems. NRL's involvement with the qualification of CPV NiH2 batteries dates back to 1988 when COMSAT and Johnson Controls, Inc. initiated a joint effort to fly the first ever NiH2 CPV in space. A later NRL-JCI cooperative research and development agreement led to the launch of a space experiment in 1993 and to the use of a single NiH2 CPV battery on the BMDO Clementine spacecraft in 1994. NRL initiated procurement of two, 50 Ah CPV NiH2 batteries in the Fall of 1992. The two batteries were delivered to NRL in June 1994. NiH2 CPV batteries have almost 2x the specific energy (Wh/kg) of nickel cadium batteries and 2x the energy density (Wh/l) of individual pressure vessel NiH2 CPV's. This presentation discusses the results of electrical and mechanical qualification tests conducted at NRL. The tests included electrical characterization, standard capacity, random vibration, peak load, and thermal vacuum. The last slides of the presentation show initial results from the life cycle tests of the second NiH2 CPV battery at 40% depth of discharge and a temperature of 10 C.

  8. The 50 Ah NiH2 CPV qualification tests

    NASA Astrophysics Data System (ADS)

    Garner, J. C.; Barnes, Wilbert L.; Hickman, Gary L.

    1995-02-01

    In 1992, the Naval Research Laboratory (NRL) started a program to qualify a large diameter common pressure vessel (CPV) nickel-hydrogen (NiH2) batteries for use on future Navy/NRL spacecraft electrical power subsystems. NRL's involvement with the qualification of CPV NiH2 batteries dates back to 1988 when COMSAT and Johnson Controls, Inc. initiated a joint effort to fly the first ever NiH2 CPV in space. A later NRL-JCI cooperative research and development agreement led to the launch of a space experiment in 1993 and to the use of a single NiH2 CPV battery on the BMDO Clementine spacecraft in 1994. NRL initiated procurement of two, 50 Ah CPV NiH2 batteries in the Fall of 1992. The two batteries were delivered to NRL in June 1994. NiH2 CPV batteries have almost 2x the specific energy (Wh/kg) of nickel cadium batteries and 2x the energy density (Wh/l) of individual pressure vessel NiH2 CPV's. This presentation discusses the results of electrical and mechanical qualification tests conducted at NRL. The tests included electrical characterization, standard capacity, random vibration, peak load, and thermal vacuum. The last slides of the presentation show initial results from the life cycle tests of the second NiH2 CPV battery at 40% depth of discharge and a temperature of 10 C.

  9. Non-dioxin-like AhR ligands in a mouse peanut allergy model.

    PubMed

    Schulz, Veronica J; Smit, Joost J; Huijgen, Veerle; Bol-Schoenmakers, Marianne; van Roest, Manon; Kruijssen, Laura J W; Fiechter, Daniëlle; Hassing, Ine; Bleumink, Rob; Safe, Stephen; van Duursen, Majorie B M; van den Berg, Martin; Pieters, Raymond H H

    2012-07-01

    Recently, we have shown that AhR activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses sensitization to peanut at least in part by inducing a functional shift toward CD4(+)CD25(+)Foxp3(+) T cells. Next to TCDD, numerous other AhR ligands have been described. In this study, we investigated the effect of three structurally different non-dioxin-like AhR ligands, e.g., 6-formylindolo[3,2-b]carbazole (FICZ), β-naphthoflavone (β-NF), and 6-methyl-1,3,8-trichlorodibenzofuran (6-MCDF), on peanut sensitization. Female C57BL/6 mice were sensitized by administering peanut extract (PE) by gavage in the presence of cholera toxin. Before and during peanut sensitization, mice were treated with FICZ, β-NF, or 6-MCDF. AhR gene transcription in duodenum and liver was investigated on day 5, even as the effect of these AhR ligands on CD4(+)CD25(+)Foxp3(+) T(reg) cells in spleen and mesenteric lymph nodes (MLNs). Mice treated with TCDD were included as a positive control. Furthermore, the murine reporter cell line H1G1.1c3 (CAFLUX) was used to investigate the possible role of metabolism of TCDD, FICZ, β-NF, and 6-MCDF on AhR activation in vitro. TCDD, but not FICZ, β-NF, and 6-MCDF, suppressed sensitization to peanut (measured by PE-specific IgE, IgG1, IgG2a and PE-induced interleukin (IL)-5, IL-10, IL-13, IL-17a, IL-22, and interferon-γ). In addition, FICZ, β-NF, and 6-MCDF treatments less effectively induced AhR gene transcription (measured by gene expression of AhR, AhRR, CYP1A1, CYP1A2, CYP1B1) compared with TCDD-treated mice. Furthermore, FICZ, β-NF and 6-MCDF did not increase the percentage of CD4(+)CD25(+)Foxp3(+) T(reg) cells in spleen and mesenteric lymph nodes compared with PE-sensitized mice, in contrast to TCDD. Inhibition of metabolism in vitro increased AhR activation. Together, these data shows that TCDD, but not FICZ, β-NF, and 6-MCDF suppresses sensitization to peanut. Differences in metabolism, AhR binding and subsequent gene transcription might

  10. Far-Infrared Water Line Emissions from Circumstellar Outflows

    NASA Technical Reports Server (NTRS)

    Chen, Wesley; Neufeld, David A.

    1995-01-01

    We have modeled the far-infrared water line emission expected from circumstellar outflows from oxygen-rich late-type stars, as a function of the mass-loss rate and the terminal outflow velocity. For each mass-loss rate and terminal outflow velocity considered, we computed self-consistently the gas density, temperature, outflow velocity, and water abundance as a function of distance from the star. We then used an escape probability method to solve for the equilibrium level populations of 80 rotational states of water and thereby obtained predictions for the luminosity of a large number of far-infrared rotational transitions of water. In common with previous models, our model predicts that water will be copiously produced in the warm circumstellar gas and that water rotational emission will dominate the radiative cooling. However, our use of a realistic radiative cooling function for water leads to a lower gas temperature than that predicted in previous models. Our predictions for the far-infrared water line luminosities are consequently significantly smaller than those obtained in previous studies. Observations to be carried out by the Infrared Space Observatory will provide a crucial test of the models presented here.

  11. PROTOSTELLAR OUTFLOW HEATING IN A GROWING MASSIVE PROTOCLUSTER

    SciTech Connect

    Wang Ke; Wu Yuefang; Zhang Huawei; Zhang Qizhou; Li Huabai

    2012-02-15

    The dense molecular clump P1 in the infrared dark cloud complex G28.34+0.06 harbors a massive protostellar cluster at its extreme youth. Our previous Submillimeter Array observations revealed several jet-like CO outflows emanating from the protostars, indicative of intense accretion and potential interaction with ambient natal materials. Here, we present the Expanded Very Large Array spectral line observations toward P1 in the NH{sub 3} (J,K) = (1,1), (2,2), (3,3) lines, as well as H{sub 2}O and class I CH{sub 3}OH masers. Multiple NH{sub 3} transitions reveal the heated gas widely spread in the 1 pc clump. The temperature distribution is highly structured; the heated gas is offset from the protostars, and morphologically matches the outflows very well. Hot spots of spatially compact, spectrally broad NH{sub 3} (3,3) emission features are also found coincident with the outflows. A weak NH{sub 3} (3,3) maser is discovered at the interface between an outflow jet and the ambient gas. These findings suggest that protostellar heating may not be effective in suppressing fragmentation during the formation of massive cores.

  12. Effects of stellar outflows on interstellar sulfur oxide chemistry

    NASA Technical Reports Server (NTRS)

    Welch, W. J.; Vogel, S.; Terebey, S.; Dreher, J.; Jackson, J.; Carlstrom, J.

    1986-01-01

    Interferometer Maps with 2" to 6" resolution of a number of regions with active star formation (Orion A, W49, W51, SGRB2) show that the distribution of the molecule SO is very compact around stellar outflow sources. Both SO and SO2 were studied near three outflows, OrionA/IRc2 and two sources in W49. The two molecules have similar distributions and abundances. More than 95% of the emission comes from regions whose extents are only .05 to .2 pc., being larger around the more energetic sources. Their spectra are broad, 30 km/sec or more, suggesting that the oxide production is associated with the flows. The outflows are identified by water masers and by extended bipolar flows in SiO. Maps in other molecules, such as HCO+ and CS, which have similar collisional excitation requirements, have much greater spatial extent. Thus it appears that the SO and SO2 abundances are truly compact and are closely associated with the outflows.

  13. Reactive nitrogen chemistry in Mexico City outflow - a unique case

    NASA Astrophysics Data System (ADS)

    Flocke, F.; Weinheimer, A.; Hodzic, A.; Emmons, L.; McKenna, D.; Tie, X.; Madronich, S.; Zheng, W.; Montzka, D.; Knapp, D.; Campos, T.; Apel, E.; Hills, A.; Mauldin, L.; Cantrell, C.; Anderson, R.; Kosciuch, E.; Jimenez, J.; Decarlo, P.; Dunlea, E.; Aiken, A.; Atlas, E.; Blake, D.; Meinardi, S.; Baker, A.; Beyersdorf, A.; Karl, T.; Clarke, T.; Shinozuka, Y.; McNaughton, C.; Zhou, J.; Springston, S.; Skamarock, W.; Fast, J.; Voss, P.; Zaveri, R.; Wennberg, P.; Crounse, J.; McCabe, D.

    2007-12-01

    The chemistry and fate of reactive nitrogen emitted from Mexico City is examined. Measurements of NOx, NOy, PANs, alkyl nitrates, HNO3, and particulate nitrate were made on board the NCAR/NSF C-130 aircraft during the 2006 MILAGRO campaign. Near- and far-field outflow from the Mexico City metropolitan area was probed by the C-130 ranging from city overflights to a distance of 1000 km from the city. Reactive nitrogen and CO measurements made on board the DOE G-1 aircraft are also used. In addition, Mexico City outflow was successfully tagged by two radio controlled CMET Balloons and the same air was measured on two consecutive days during the March 18/19 outflow event. The reactive nitrogen data is examined with regard to NOy partitioning, ozone formation efficiency, and the ultimate fate of NOy, as a function of time and distance from the city. The NOx sequestration chemistry is examined using the WRF-Chem model. Because of the unique conditions in Mexico City with regard to altitude and climate as well as the high particle loading in the area the chemistry in the Mexico City outflow is very different compared to other mega-cities such as New York City. These differences and the resulting impacts on the region around the city will be discussed.

  14. Morphology of Fresh Outflow Channel Deposits on Mars

    NASA Technical Reports Server (NTRS)

    Rice, J. W., Jr.; Parker, T. J.; Russell, A. J.; Knudsen, O.

    2002-01-01

    We interpret the channel surface of Athabasca and Marte Valles to be fresh former ice-rich fluvial (hyperconcentrated) deposits rather than volcanic flows. Simply stated, this is what a fresh outflow channel deposit would look like. Additional information is contained in the original extended abstract.

  15. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China

    SciTech Connect

    Chang Lang; Shu Tao; Wenxin Liu; Yanxu Zhang; Staci Simonich

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Nino/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds. 38 refs., 4 figs.

  16. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China.

    PubMed

    Lang, Chang; Tao, Shu; Liu, Wenxin; Zhang, Yanxu; Simonich, Staci

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Niño/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds.

  17. Extremely Energetic Outflow and Decelerated Expansion in W49N

    NASA Astrophysics Data System (ADS)

    Liu, Tie; Kim, Kee-Tae; Wu, Yuefang; Li, Di; Lee, Chang-Won; De Pree, Christopher G.; Qin, Sheng-Li; Wang, Ke; Tatematsu, Ken'ichi; Zhang, Qizhou; Mardones, Diego; Liu, Sheng-Yuan; Cho, Se-Hyung

    2015-09-01

    W49N is a mini-starburst in the Milky Way and is thus an ideal laboratory for high-mass star formation studies. Due to its large distance ({11.1}-0.7+0.9 kpc), the kinematics inside and between the dense molecular clumps in W49N are far from well-understood. The Submillimeter Array observations resolved the continuum emission into two clumps. The molecular line observation of SO2 ({28}{4,24}-{28}{3,25}) suggests that the two clumps have a velocity difference of ˜7 km s-1. The eastern clump is very close to two radio sources “G1” and “G2,” and the western clump coincides with a radio source “B.” The HCN (3-2) line reveals an extremely energetic outflow, which is among the most energetic molecular outflows in the Milky Way. This is the first report of high-velocity molecular outflow detection in W49N. The outflow jet might be in precession, which could account for the distribution, velocity, and rotation of water maser spots. Three absorption systems are identified in {{HCO}}+ (3-2) spectra. The absorption features are blueshifted with respect to the emission of SO2 ({28}{4,24}-{28}{3,25}) lines, indicating that a cold layer is expanding in front of the warm gas. Further analysis indicates that the expansion is decelerated from the geometric expansion centers.

  18. Outflow of polycyclic aromatic hydrocarbons from Guangdong, southern China.

    PubMed

    Lang, Chang; Tao, Shu; Zhang, Gang; Fu, Jiamo; Simonich, Staci

    2007-12-15

    The atmospheric outflow of polycyclic aromatic hydrocarbons (PAHs) from Guangdong, China, a region of high PAH emission, was modeled using a potential receptor influence function (PRIF) probabilistic model which was based on a spatially resolved PAH inventory and air mass forward-trajectory calculations. Photochemical degradation and deposition (dry and wet) of PAHs during atmospheric transport were taken into consideration. On average, 48% of the PAHs (by mass) remained in the atmosphere for a transport period of 5 days, staying within the boundary of the source region. The medium molecular weight PAHs (four rings) were predicted to travel longer distances in the atmosphere than the low (three rings) or high molecular weight PAHs (five rings) because they are less photodegradable than the lower molecular weight, gas-phase PAHs and less likelyto undergo wet and dry depositions than the higher molecular weight, particulate phase PAHs. Under the strong influence of the East Asian monsoons in winter, the predominant outflow pattern of PAHs from Guangdong was to the South China Sea and Southeast Asian countries. In summer, PAHs were transported primarily to northern mainland China. Under particular weather conditions in winter, the PAH-containing air masses were lifted by cold fronts or convection and transported toward the Pacific Ocean by westerly winds. In addition to the distinct seasonality in PAH dispersion and outflow, interannual long-term variation in the outflow is likely influenced by El Niño and southern oscillation.

  19. Exposure to Diesel Exhaust Particle Extracts (DEPe) Impairs Some Polarization Markers and Functions of Human Macrophages through Activation of AhR and Nrf2

    PubMed Central

    Jaguin, Marie; Fardel, Olivier; Lecureur, Valérie

    2015-01-01

    Macrophages (MΦ), well-known to play an important role in immune response, also respond to environmental toxic chemicals such as diesel exhaust particles (DEP). Potential effects of DEPs towards MΦ polarization, a key hall-mark of MΦ physiology, remain however poorly documented. This study was therefore designed to evaluate the effects of a reference DEP extract (DEPe) on human MΦ polarization. Human blood monocytes-derived MΦ were incubated with IFNγ+LPS or IL-4 to obtain M1 and M2 subtypes, respectively; a 24 h exposure of polarizing MΦ to 10 μg/ml DEPe was found to impair expression of some macrophagic M1 and M2 markers, without however overall inhibition of M1 and M2 polarization processes. Notably, DEPe treatment increased the secretion of the M1 marker IL-8 and the M2 marker IL-10 in both MΦ subtypes, whereas it reduced lipopolysaccharide-induced IL-6 and IL-12p40 secretion in M1 MΦ. In M2 MΦ, DEPe exposure led to a reduction of CD200R expression and of CCL17, CCL18 and CCL22 secretion, associated with a lower chemotaxis of CCR4-positive cells. DEPe activated the Nrf2 and AhR pathways and induced expression of their reference target genes such as Hmox-1 and cytochrome P-4501B1 in M1 and M2 MΦ. Nrf2 or AhR silencing through RNA interference prevented DEPe-related down-regulation of IL-6. AhR silencing also inhibited the down-secretion of IL-12p40 and CCL18 in M1- and M2-DEPe-exposed MΦ, respectively. DEPs are therefore likely to alter expression of some M1 and M2 markers in an AhR- and Nrf2-dependent manner; such regulations may contribute to deleterious immune effects of atmospheric DEP. PMID:25710172

  20. ARE MOLECULAR OUTFLOWS AROUND HIGH-MASS STARS DRIVEN BY IONIZATION FEEDBACK?

    SciTech Connect

    Peters, Thomas; Klessen, Ralf S.; Klaassen, Pamela D.; Mac Low, Mordecai-Mark; Banerjee, Robi

    2012-11-20

    The formation of massive stars exceeding 10 M {sub Sun} usually results in large-scale molecular outflows. Numerical simulations, including ionization, of the formation of such stars show evidence for ionization-driven molecular outflows. Here we examine whether the outflows seen in these models reproduce the observations. We compute synthetic ALMA and CARMA maps of CO emission lines of the outflows, and compare their signatures to existing single-dish and interferometric data. We find that the ionization-driven models can only reproduce weak outflows around high-mass star-forming regions. We argue that expanding H II regions probably do not represent the dominant mechanism for driving observed outflows. We suggest instead that observed outflows are driven by the collective action of the outflows from the many lower-mass stars that inevitably form around young massive stars in a cluster.

  1. The Prevalence of Gas Outflows in Type 2 AGNs

    NASA Astrophysics Data System (ADS)

    Woo, Jong-Hak; Bae, Hyun-Jin; Son, Donghoon; Karouzos, Marios

    2016-02-01

    To constrain the nature and fraction of the ionized gas outflows in active galactic nuclei (AGNs), we perform a detailed analysis on gas kinematics as manifested by the velocity dispersion and shift of the [{{O}}\\{{III}}] λ5007 emission line, using a large sample of ˜39,000 type 2 AGNs at z < 0.3. First, we confirm a broad correlation between [{{O}} {{III}}] and stellar velocity dispersions, indicating that the bulge gravitational potential plays a main role in determining the [{{O}} {{III}}] kinematics. However, [{{O}} {{III}}] velocity dispersion is on average larger than stellar velocity dispersion by a factor of 1.3-1.4 for AGNs with double Gaussian [{{O}} {{III}}], suggesting that the non-gravitational component, i.e., outflows, is almost comparable to the gravitational component. Second, the increase of the [{{O}} {{III}}] velocity dispersion (after normalized by stellar velocity dispersion) with both AGN luminosity and Eddington ratio suggests that non-gravitational kinematics are clearly linked to AGN accretion. The distribution in the [{{O}} {{III}}] velocity-velocity dispersion diagram dramatically expands toward large values with increasing AGN luminosity, implying that the launching velocity of gas outflows increases with AGN luminosity. Third, the majority of luminous AGNs present the non-gravitational kinematics in the [{{O}} {{III}}] profile. These results suggest that ionized gas outflows are prevalent among type 2 AGNs. On the other hand, we find no strong trend of the [{{O}} {{III}}] kinematics with radio luminosity, once we remove the effect of the bulge gravitational potential, indicating that ionized gas outflows are not directly related to radio activity for the majority of type 2 AGNs.

  2. A young bipolar outflow from IRAS15398-3359

    NASA Astrophysics Data System (ADS)

    Bjerkeli, Per; Jørgensen, Jes K.

    2015-08-01

    The Class 0 protostar IRAS 15398-3359 is located in the Lupus I cloud at a distance of 155 pc. The source is known to harbour a molecular outflow, but the region has not attracted much interest until recently. IRAS 15398 is known to show interesting chemical signatures and being one of the very nearby, young outflow sources makes it an excellent target for detailed studies of the gas kinematics of different species.We present observations of several molecular species, carried out with the Submillimeter Array and ALMA, towards the IRAS 15398 outflow. The analysis of CO emission show obvious signs of episodic mass ejections, with a dynamical time scale between the knots in the jet, of the order 100 years. This is consistent with recent ALMA results where luminosity outbursts are estimated to occur on similar time-scales. The physical properties of the outflow, such as mass, momentum, momentum rate, mechanical luminosity, kinetic energy and mass-loss rate are estimated at relatively low values. We argue that this source is of a very young age, possibly younger than ~1000 years. This is consistent with recent studies of the kinematics of the inner envelope/disk. The observed line profiles were compared to full 3D radiative transfer models of the source, constructed with the Line Modelling Engine (LIME). The observed line shapes can only be understood when considering several distinctly different physical components, viz. the outflow cavity, the infalling envelope and the surrounding cloud material. This allows us to put quantitative constraints on the kinematics of the material close to the central source.

  3. Multiwavelength Spectroscopy of the Bipolar Outflow from Cepheus E

    NASA Astrophysics Data System (ADS)

    Smith, Michael D.; Froebrich, Dirk; Eislöffel, Jochen

    2003-07-01

    Cepheus E is the site of an exceptional example of a protostellar outflow with a very young dynamical age and extremely high near-infrared luminosity. We combine molecular spectroscopic data from the submillimeter to the near-infrared in order to interpret the rotational excitation of CO and the rovibrational excitation of H2. We conclude that C-type shocks with a paraboloidal bow shock geometry can simultaneously explain all the molecular excitations. Extinction accounts for the deviation of the column densities from local thermodynamic equilibrium. A difference in the extinction between the red- and blueshifted outflow lobes may account for the measured flux difference. The outflow is deeply embedded in a clump of density 105 cm-3, yet a good fraction of atomic hydrogen, about 40%, is required to explain the excitation and statistical equilibrium. We propose that this atomic component arises, self-consistently, from the dissociated gas at the apex of the leading bow shocks and the relatively long molecule reformation time. At least 20 bow shocks are required in each lobe, although these may be subdivided into smaller bows and turbulent shocked regions. The total outflow mechanical power and cooling amounts to over 30 Lsolar, almost half the source's bolometric luminosity. Nevertheless, only about 6% of the clump mass has been set in outward motion by the outflow, allowing a collapse to continue. Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA.

  4. Overconsumption, outflows and the quenching of satellite galaxies

    NASA Astrophysics Data System (ADS)

    McGee, Sean L.; Bower, Richard G.; Balogh, Michael L.

    2014-07-01

    The baryon cycle of galaxies is a dynamic process involving the intake, consumption and ejection of vast quantities of gas. In contrast, the conventional picture of satellite galaxies has them methodically turning a large gas reservoir into stars until this reservoir is forcibly removed due to external ram pressure. This picture needs revision. Our modern understanding of the baryon cycle suggests that in some regimes the simple interruption of the fresh gas supply may quench satellite galaxies long before stripping events occur, a process we call overconsumption. We compile measurements from the literature of observed satellite quenching times at a range of redshifts to determine if satellites are principally quenched through orbit-based gas stripping events - either direct stripping of the disc (ram pressure stripping) or the extended gas halo (strangulation) - or from internally driven star formation outflows via overconsumption. These time-scales show significant deviations from the evolution expected for gas stripping mechanisms and suggest that either ram pressure stripping is much more efficient at high redshift, or that secular outflows quench satellites before orbit-based stripping occurs. Given the strong redshift evolution of star formation rates, at high redshift even moderate outflow rates will lead to extremely short delay times with the expectation that high-redshift (z > 1.5) satellites will be quenched almost immediately following the cessation of cosmological inflow. Observations of high-redshift satellites give an indirect but sensitive measure of the outflow rate, with current measurements suggesting that outflows are no larger than 2.5 times the star formation rate for galaxies with a stellar mass of 1010.5 M⊙.

  5. Avian Influenza A(H5N1) and A(H9N2) Seroprevalence and Risk Factors for Infection Among Egyptians: A Prospective, Controlled Seroepidemiological Study

    PubMed Central

    Gomaa, Mokhtar R.; Kayed, Ahmed S.; Elabd, Mona A.; Zeid, Dina Abu; Zaki, Shaimaa A.; El Rifay, Amira S.; Sherif, Lobna S.; McKenzie, Pamela P.; Webster, Robert G.; Webby, Richard J.; Ali, Mohamed A.; Kayali, Ghazi

    2015-01-01

    Background. A(H5N1) and A(H9N2) avian influenza viruses are enzootic in Egyptian poultry, and most A(H5N1) human cases since 2009 have occurred in Egypt. Our understanding of the epidemiology of avian viruses in humans remains limited. Questions about the frequency of infection, the proportion of infections that are mild or subclinical, and the case-fatality rate remain largely unanswered. Methods. We conducted a 3-year, prospective, controlled, seroepidemiological study that enrolled 750 poultry-exposed and 250 unexposed individuals in Egypt. Results. At baseline, the seroprevalence of anti-A(H5N1) antibodies (titer, ≥80) among exposed individuals was 2% significantly higher than that among the controls (0%). Having chronic lung disease was a significant risk factor for infection. Antibodies against A(H9N2) were not detected at baseline when A(H9N2) was not circulating in poultry. At follow-up, A(H9N2) was detected in poultry, and consequently, the seroprevalence among exposed humans was between 5.6% and 7.5%. Vaccination of poultry, older age, and exposure to ducks were risk factors for A(H9N2) infection. Conclusions. Results of this study indicate that the number of humans infected with avian influenza viruses is much larger than the number of reported confirmed cases. In an area where these viruses are enzootic in the poultry, human exposure to and infection with avian influenza becomes more common. PMID:25355942

  6. Identification and expression of aryl hydrocarbon receptors (AhR1 and AhR2) provide insight in an evolutionary context regarding sensitivity of white sturgeon (Acipenser transmontanus) to dioxin-like compounds.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Giesy, John P; Hecker, Markus

    2014-05-01

    Sturgeons are ancient fishes, which are endangered in many parts of the world. Due to their benthic nature and longevity, sturgeon are at great risk of exposure to bioaccumulative contaminants such as dioxin-like compounds (DLCs). Despite their endangered status, little research has been conducted to characterize the relative sensitivity of sturgeons to DLCs. Proper assessment of risk of DLCs posed to these fishes therefore, requires a better understanding of this sensitivity and the factors that are driving it. Adverse effects associated with exposure to DLCs are mediated by the aryl hydrocarbon receptor (AhR). This study identified and characterized two distinct AhRs, AhR1 and AhR2, in white sturgeon (Acipenser transmontanus) for the first time as a first step in studying the relative sensitivities of sturgeons to DLCs. Furthermore, tissue-specific expression of both AhRs under basal conditions and in response to exposure to the model DLC, β-naphthoflavone (βNF), was determined. The sequence of amino acids of AhR1 of white sturgeon had greater similarity to AhRs of tetrapods, including amphibians, birds, and mammals, than to AhR1s of other fishes. The sequence of amino acids in the ligand binding domain of the AhR1 had greater than 80% similarity to AhRs known to bind DLCs and was less similar to AhRs not known to bind DLCs. AhR2 of white sturgeon had greatest similarity to AhR2 of other fishes. Profiles of expression of AhR1 and AhR2 in white sturgeon were distinct from those known in other fishes and appear more similar to profiles observed in birds. Expressions of both AhR1 and AhR2 of white sturgeon were greatest in liver and heart, which are target organs for DLCs. Furthermore, abundances of transcripts of AhR1 and AhR2 in all tissues from white sturgeon were greater than controls (up to 35-fold) following exposure to βNF. Based upon both AhRs having similar abundances of transcript in target organs of DLC toxicity, both AhRs being up-regulated following

  7. Identification and expression of aryl hydrocarbon receptors (AhR1 and AhR2) provide insight in an evolutionary context regarding sensitivity of white sturgeon (Acipenser transmontanus) to dioxin-like compounds.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Giesy, John P; Hecker, Markus

    2014-05-01

    Sturgeons are ancient fishes, which are endangered in many parts of the world. Due to their benthic nature and longevity, sturgeon are at great risk of exposure to bioaccumulative contaminants such as dioxin-like compounds (DLCs). Despite their endangered status, little research has been conducted to characterize the relative sensitivity of sturgeons to DLCs. Proper assessment of risk of DLCs posed to these fishes therefore, requires a better understanding of this sensitivity and the factors that are driving it. Adverse effects associated with exposure to DLCs are mediated by the aryl hydrocarbon receptor (AhR). This study identified and characterized two distinct AhRs, AhR1 and AhR2, in white sturgeon (Acipenser transmontanus) for the first time as a first step in studying the relative sensitivities of sturgeons to DLCs. Furthermore, tissue-specific expression of both AhRs under basal conditions and in response to exposure to the model DLC, β-naphthoflavone (βNF), was determined. The sequence of amino acids of AhR1 of white sturgeon had greater similarity to AhRs of tetrapods, including amphibians, birds, and mammals, than to AhR1s of other fishes. The sequence of amino acids in the ligand binding domain of the AhR1 had greater than 80% similarity to AhRs known to bind DLCs and was less similar to AhRs not known to bind DLCs. AhR2 of white sturgeon had greatest similarity to AhR2 of other fishes. Profiles of expression of AhR1 and AhR2 in white sturgeon were distinct from those known in other fishes and appear more similar to profiles observed in birds. Expressions of both AhR1 and AhR2 of white sturgeon were greatest in liver and heart, which are target organs for DLCs. Furthermore, abundances of transcripts of AhR1 and AhR2 in all tissues from white sturgeon were greater than controls (up to 35-fold) following exposure to βNF. Based upon both AhRs having similar abundances of transcript in target organs of DLC toxicity, both AhRs being up-regulated following

  8. AHS and CASI Processing for the REFLEX Remote Sensing Campaign: Methods and Results

    NASA Astrophysics Data System (ADS)

    De Miguel, Eduardo; Jiménez, Marcos; Pérez, Irene; de la Cámara, Óscar G.

    2015-12-01

    The airborne spectroradiometers AHS and CASI were used as a source of hyperspectral and thermal remote sensing data during the REFLEX campaign. Data geolocation and a first simple atmospheric correction was performed by INTA in near-real time with a specific on-site setup and distributed to all campaign participants. In this paper we present briefly the AHS and CASI REFLEX flight campaign followed by a detailed description of the methodology used for image processing and finally the results obtained in terms of image quality. As a conclusion, near-real time processing for AHS and CASI level 1 geolocated products was successful as most of CASI level 2 results but further work is needed for achieving accurate AHS level 2 products.

  9. The 50Ah NiH2 cell life test results

    NASA Technical Reports Server (NTRS)

    Jamin, Thierry; Puig, Olivier

    1992-01-01

    Information is given in viewgraph form for the 50 AhNiH2 cell life test results. Information is given on pressure vessel design, electrochemical/stack design, cell electrical characteristics, and cell life test results.

  10. Grain formation around carbon stars. 1: Stationary outflow models

    NASA Technical Reports Server (NTRS)

    Egan, Michael P.; Leung, Chun Ming

    1995-01-01

    Asymptotic giant branch (AGB) stars are known to be sites of dust formation and undergo significant mass loss. The outflow is believed to be driven by radiation pressure on grains and momentum coupling between the grains and gas. While the physics of shell dynamics and grain formation are closely coupled, most previous models of circumstellar shells have treated the problem separately. Studies of shell dynamics typically assume the existence of grains needed to drive the outflow, while most grain formation models assume a constant veolcity wind in which grains form. Furthermore, models of grain formation have relied primarily on classical nucleation theory instead of using a more realistic approach based on chemical kinetics. To model grain formation in carbon-rich AGB stars, we have coupled the kinetic equations governing small cluster growth to moment equations which determine the growth of large particles. Phenomenological models assuming stationary outflow are presented to demonstrate the differences between the classical nucleation approach and the kinetic equation method. It is found that classical nucleation theory predicts nucleation at a lower supersaturation ratio than is predicted by the kinetic equations, resulting in significant differences in grain properties. Coagulation of clusters larger than monomers is unimportant for grain formation in high mass-loss models but becomes more important to grain growth in low mass-loss situations. The properties of the dust grains are altered considerably if differential drift velocities are ignored in modeling grain formation. The effect of stellar temperature, stellar luminosity, and different outflow velocities are investigated. The models indicate that changing the stellar temperature while keeping the stellar luminosity constant has little effect on the physical parameters of the dust shell formed. Increasing the stellar luminosity while keeping the stellar temperature constant results in large differences in

  11. Characterizing Quasar Outflows III: SEDs, and Bolometric Luminosity Estimates

    NASA Astrophysics Data System (ADS)

    Richmond, Joseph; Robbins, J. M.; Ganguly, R.; Stark, M. A.; Christenson, D. H.; Derseweh, J. A.; Townsend, S. L.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In this poster, we add photometry from both the Two Micron All-Sky Survey (2MASS) and from the Wide-Field Infrared Survey Explorer (WISE). 2MASS photometry covers the rest-frame optical regime of these qusars, while the WISE W1, W2, and W3 bands cover the rest-frame wavelength ranges 0.9-1.27 micron, 1.35-1.75 micron, and 2.52-5.51 micron, respectively. The preliminary release of WISE data cover 3800 of our quasars. In an accompnying poster, we have subjectively divided these quasars into four categories: broad absorption-line quasars (2700 objects), associated absorption-line quasars (1700 objects), reddened quasars (160 objects), and unabsorbed/unreddened quasars (6300 objects). Here, we present average SEDs for these subsamples, estimates of bolometric luminosity, and explore changes in SED based on both outflow properties and quasar physical properties. This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. 09-ADP09-0016 issued through the

  12. Depletion of H2A-H2B dimers in Saccharomyces cerevisiae triggers meiotic arrest by reducing IME1 expression and activating the BUB2-dependent branch of the spindle checkpoint.

    PubMed Central

    Hanlon, Sean E; Norris, David N; Vershon, Andrew K

    2003-01-01

    In the yeast Saccharomyces cerevisiae, diploid strains carrying homozygous hta1-htb1Delta mutations express histone H2A-H2B dimers at a lower level than do wild-type cells. Although this mutation has only minor effects on mitotic growth, it causes an arrest in sporulation prior to the first meiotic division. In this report, we show that the hta1-htb1Delta mutant exhibits reduced expression of early and middle-sporulation-specific genes and that the meiotic arrest of the hta1-htb1Delta mutant can be partially bypassed by overexpression of IME1. Additionally, deletions of BUB2 or BFA1, components of one branch of the spindle checkpoint pathway, bypass the meiotic arrest. Mutations in the other branch of the pathway or in the pachytene checkpoint are unable to suppress the meiotic block. These observations indicate that depletion of the H2A-H2B dimer blocks sporulation by at least two mechanisms: disruption of the expression of meiotic regulatory genes and activation of the spindle checkpoint. Our results show that the failure to progress through the meiotic pathway is not the result of global chromosomal alterations but that specific aspects of meiosis are sensitive to depletion of the H2A-H2B dimer. PMID:12930743

  13. The Influence of Outflow in Supercritical Accretion Flows

    NASA Astrophysics Data System (ADS)

    Zahra Zeraatgari, Fatemeh; Abbassi, Shahram; Mosallanezhad, Amin

    2016-06-01

    We solve the radiation-hydrodynamic equations of supercritical accretion flows in the presence of radiation force and outflow by using self-similar solutions. Similar to the pioneering works, in this paper we consider a power-law function for mass inflow rate as \\dot{M}\\propto {r}s. We found that s = 1 when the radiative cooling term is included in the energy equation. Correspondingly, the effective temperature profile with respect to the radius was obtained as {T}{eff}\\propto {r}-1/2. In addition, we investigated the influence of the outflow on the dynamics of the accretion flow. We also calculated the continuum spectrum emitted from the disk surface as well as the bolometric luminosity of the accretion flow. Furthermore, our results show that the advection parameter, f, depends strongly on mass inflow rate.

  14. New Spectral State of Supercritical Accretion Flow with Comptonizing Outflow

    NASA Astrophysics Data System (ADS)

    Kawashima, Tomohisa; Ohsuga, Ken; Mineshige, Shin; Heinzeller, Dominikus; Takabe, Hideaki; Matsumoto, Ryoji

    2009-08-01

    Supercritical accretion flows inevitably produce radiation-pressure driven outflows, which Compton up-scatter soft photons from the underlying accretion flow, thereby making hard emission. We performed two-dimensional radiation hydrodynamic simulations of supercritical accretion flows and outflows, while incorporating such Compton scattering effects, and demonstrated that there appears a new hard spectral state at higher photon luminosities than that of the slim-disk state. In this state, as the photon luminosity increases, the photon index decreases and the fraction of the hard emission increases. The Compton y-parameter is on the order of unity (and thus the photon index will be ˜2) when the apparent photon luminosity is ˜30LE (with LE being the Eddington luminosity) for nearly face-on sources. This explains the observed spectral hardening of the ULX NGC 1313 X-2 in its brightening phase, and thus supports the model of supercritical accretion onto stellar-mass black holes in this ULX.

  15. Nucleosynthesis in Outflows from Kerr Black Hole Accretion Disks

    SciTech Connect

    Surman, Rebecca; Mclaughlin, Gail C; Sabbatino, N.; Hix, William Raphael

    2008-01-01

    Observational evidence suggests long-duration, collapsar-type gamma-ray bursts (GRBs) may have been more common in the early universe. These events are thought to be powered by accretion disks around black holes (AD-BHs). While GRBs require AD-BHs, not all AD-BHs will power bursts and therefore their formation will be more common than GRBs themselves. Outflows from AD-BHs may therefore be important contributors to the nuclear abundances in the oldest stars, particularly for rare species or those not uniformly observed. Here we consider the nucleosynthesis in this environment starting with relativistic disk models of Kerr black holes and following the element synthesis in a parameterized outflow. We present nucleosynthesis results from a range of AD-BH models.

  16. An outflow linked to a YSO in Gum 31?

    NASA Astrophysics Data System (ADS)

    Vazzano, M. M.; Cappa, C. E.; Bosch, G.; Vásquez, J.

    2016-08-01

    We analyze the distribution of the molecular gas associated with 10349-5824, a young stellar object located on the edge of the H ii region Gum31, with the aim of investigating the existence of bipolar outflows. We use CO(2-1) line observations obtained with the APEX telescope, H line observations on the K band taken with Flamingos 2 in Gemini South and additional data from at 4.5, 8 and 24 m. J103648.97-584010.7 (1), classified as class II, coincides with extended emission in 4.5 m, suggesting the presence of bipolar flows, and with H emission at 2.12 m. Three extended sources detected in H at 0.5 and 1.5 of 1 could also suggest the presence of shocked gas. Additional evidence of bipolar outflows comes from CO(2-1) spectra.

  17. Inflow versus outflow zero-temperature dynamics in one dimension

    NASA Astrophysics Data System (ADS)

    Sznajd-Weron, Katarzyna; Krupa, Sylwia

    2006-09-01

    It has been suggested that Glauber (inflow) and Sznajd (outflow) zero-temperature dynamics for the one-dimensional Ising ferromagnet with nearest-neighbor interactions are equivalent. Here we compare the two dynamics from the analytical and computational points of view. We use the method of mapping an Ising spin system onto the dimer RSA model and show that already this simple mapping allows us to see the differences between inflow and outflow zero-temperature dynamics. Then we investigate both dynamics with synchronous, partially synchronous, and random sequential updating using the Monte Carlo technique and compare both dynamics in the number of persistent spins, clusters, mean relaxation time, and relaxation time distribution.

  18. Cirrus clouds in convective outflow during the HIBISCUS campaign

    NASA Astrophysics Data System (ADS)

    Fierli, F.; di Donfrancesco, G.; Cairo, F.; Zampieri, M.; Orlandi, E.

    2007-05-01

    Light-weight microlidar measurements were taken on-board a stratospheric balloon during the HIBISCUS 2004 campaign, held in Bauru, Brazil (22 S, 49 W). Tropical cirrus observations showed high mesoscale variability in optical and microphysical properties. The cirrus clouds were observed throughout the flight between 12 and 15 km height. It was found that the clouds were composed of different layers, characterized by a marked variability in height, thickness and optical properties. Trajectory analysis and mesoscale transport simulations clearly revealed that the clouds had formed in the outflow of a large and persistent convective region, while the observed optical properties and cloud structure variability could be linked to different residence times of convective-processed air in the upper troposphere. Mesoscale simulations were able to reproduce the supersaturation due to recent outflow, while it was necessary to consider the presence of other formation processes than convective hydration for cirrus forming in aged detrained anvils.

  19. Experimental demonstration of an inertial collimation mechanism in nested outflows.

    PubMed

    Yurchak, R; Ravasio, A; Pelka, A; Pikuz, S; Falize, E; Vinci, T; Koenig, M; Loupias, B; Benuzzi-Mounaix, A; Fatenejad, M; Tzeferacos, P; Lamb, D Q; Blackman, E G

    2014-04-18

    Interaction between a central outflow and a surrounding wind is common in astrophysical sources powered by accretion. Understanding how the interaction might help to collimate the inner central outflow is of interest for assessing astrophysical jet formation paradigms. In this context, we studied the interaction between two nested supersonic plasma flows generated by focusing a long-pulse high-energy laser beam onto a solid target. A nested geometry was created by shaping the energy distribution at the focal spot with a dedicated phase plate. Optical and x-ray diagnostics were used to study the interacting flows. Experimental results and numerical hydrodynamic simulations indeed show the formation of strongly collimated jets. Our work experimentally confirms the "shock-focused inertial confinement" mechanism proposed in previous theoretical astrophysics investigations. PMID:24785042

  20. Incidence of galactic outflows: EAGLE simulations vs SAMI observations

    NASA Astrophysics Data System (ADS)

    Tescari, E.

    2016-06-01

    I presented the results of the joint SAMI-EAGLE project on outflows I lead at the University of Melbourne. We use the highest resolution EAGLE cosmological simulations to study the incidence of supernova driven winds ejected from galaxies on the main sequence. We produce synthetic SAMI observations of outflows that we compare directly with real data. While winds are observed in only a fraction of SAMI galaxies, they appear ubiquitous among simulated star forming objects. Moreover, the velocity dispersion distribution is only weakly dependent on stellar mass (M*) and sSFR (SFR/M*). I presented additional analyses and discuss the implications of these results and how they provide important constraints to ongoing and future IFS surveys.

  1. Experimental Demonstration of an Inertial Collimation Mechanism in Nested Outflows

    NASA Astrophysics Data System (ADS)

    Yurchak, R.; Ravasio, A.; Pelka, A.; Pikuz, S.; Falize, E.; Vinci, T.; Koenig, M.; Loupias, B.; Benuzzi-Mounaix, A.; Fatenejad, M.; Tzeferacos, P.; Lamb, D. Q.; Blackman, E. G.

    2014-04-01

    Interaction between a central outflow and a surrounding wind is common in astrophysical sources powered by accretion. Understanding how the interaction might help to collimate the inner central outflow is of interest for assessing astrophysical jet formation paradigms. In this context, we studied the interaction between two nested supersonic plasma flows generated by focusing a long-pulse high-energy laser beam onto a solid target. A nested geometry was created by shaping the energy distribution at the focal spot with a dedicated phase plate. Optical and x-ray diagnostics were used to study the interacting flows. Experimental results and numerical hydrodynamic simulations indeed show the formation of strongly collimated jets. Our work experimentally confirms the "shock-focused inertial confinement" mechanism proposed in previous theoretical astrophysics investigations.

  2. On the Thermal Line Emission from the Outflows in Ultraluminous X-Ray Sources

    NASA Astrophysics Data System (ADS)

    Xu, Ya-Di; Cao, Xinwu

    2016-08-01

    The atomic features in the X-ray spectra of ultraluminous X-ray sources (ULXs) may be associated with the outflow, which may provide a way to explore the physics of the ULXs. We construct a conical outflow model and calculate the thermal X-ray Fe emission lines from the outflows. Our results show that thermal line luminosity decreases with increasing outflow velocity and/or opening angle of the outflow for a fixed kinetic power of the outflows. Assuming the kinetic power of the outflows to be comparable with the accretion power in the ULXs, we find that the equivalent width can be several eV for the thermal X-ray Fe emission line from the outflows in the ULXs with stellar-mass black holes. The thermal line luminosity is proportional to 1/M bh (M bh is the black hole mass of the ULX). The equivalent width decreases with the black hole mass, which implies that the Fe line emission from the outflows can hardly be detected if the ULXs contain intermediate-mass black holes. Our results suggest that the thermal X-ray Fe line emission should be preferentially be detected in the ULXs with high kinetic power slowly moving outflows from the accretion disks surrounding stellar-mass black holes/neutron stars. The recently observed X-ray atomic features of the outflows in a ULX may imply that it contains a stellar-mass black hole.

  3. Testing the Radiative-Driving Hypothesis of Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Stark, Michele A.; Ganguly, R.; Gallagher, S. C.; Gibson, R.; Brotherton, M. S.

    2011-01-01

    Outflows are seen prominently in the UV spectra of Broad Absorption Line (BAL) QSOs. Models of radiatively-driven outflows predict that the velocity should scale with UV luminosity. Observations show that the UV luminosity only provides a cap to the velocity. One explanation is that the X-ray absorbing gas in an individual quasar provides a shield that improves its radiative-driving efficiency. That is, quasars with thick shields can accelerate gas to higher velocity. X-ray observations of BALQSOs support this in the sense that BALQSOs with more soft X-ray absorption tend to have higher velocity outflows. But there is much scatter in this trend, making the underlying physics difficult to extract. To combat this, we conducted an experiment using exploratory Chandra-ACIS observations of 12 carefully-selected z=1.7-2.0 BALQSOs. These BALQSOs were chosen to have very narrow ranges in (1) UV luminosity, (2) UV spectral shape, and (3) absorption velocity width. Within this otherwise uniform sample, the outflow velocities range from 4500km/s to 18000km/s, a factor of four. All objects are detected in the full band (0.5-8keV), with count rates in the range (0.5-5)e-3 cps, and have hardness ratios in the range -0.6 to 0.3. We compare the X-ray brightnesses and spectral shapes of our sample with those of more diverse samples of BALQSOs. We gratefully acknowledge support through Chandra grant GO9-0120X.

  4. Mars Ion Outflow and Escape - Solar Cycle Dependence

    NASA Astrophysics Data System (ADS)

    Lundin, Rickard; Barabash, Stas; Nilsson, Hans; Yamauchi, Masatoshi; Dubinin, Edic

    2013-04-01

    With 9 years of data from the ASPERA-3 experiment on Mars Express (MEX) it is now feasible to analyze the solar cycle impact on the ion outflow and escape from Mars - from the end of solar cycle 23, through solar minimum 2008, up to the solar maximum of cycle 24. The study is based on average fluxes of low-energy (<300 eV) O+ and O2+, derived for selected periods when MEX traversed the central tail near the noon-midnight meridian. A time series plot of average O+ and O2+ fluxes, and solar activity proxies (RI and F10.7) display how the heavy ion outflow from Mars vary with solar activity. We note that the average O+, O2+ flux increased by a factor of ≈10 from 2008 (solar minimum) to 2013, while RI rose from ≈ 3 to 60, and a normalized F10.7* (F10.7-60) rose from ≈6 - 60, F10.7* suggesting a close correlation with heavy ion outflow. A correlation analysis between the two solar activity proxies (RI and F10.7*) and the O+ and O2+ average flux gives correlation coefficients (R2) greater than 0.6, i.e. there is a strong positive correlation between the energization and outflow of ionospheric heavy ions and solar activity. A preliminary estimate of the total escape rate of heavy ions (O++O2+) from Mars is ≈1-2·1024 ions/s (2008, solar minimum) and 1-2·1025 ions/s (2013, solar maximum?)

  5. Biological role of Trichoderma harzianum-derived platelet-activating factor acetylhydrolase (PAF-AH) on stress response and antagonism.

    PubMed

    Yu, Chuanjin; Fan, Lili; Wu, Qiong; Fu, Kehe; Gao, Shigang; Wang, Meng; Gao, Jinxin; Li, Yaqian; Chen, Jie

    2014-01-01

    We investigated the properties of platelet-activating factor acetylhydrolase (PAF-AH) derived from Trichoderma harzianum. The enzyme, comprised of 572 amino acids, shares high homology with PAF-AH proteins from T. koningii and other microbial species. The optimum enzymatic activity of PAF-AH occurred at pH 6 in the absence of Ca2+ and it localized in the cytoplasm, and we observed the upregulation of PAF-AH expression in response to carbon starvation and strong heat shock. Furthermore, PAF-AH knockout transformant growth occurred more slowly than wild type cells and over-expression strains grown in SM medium at 37°C and 42°C. In addition, PAF-AH expression significantly increased under a series of maize root induction assay. Eicosanoic acid and ergosterol levels decreased in the PAF-AH knockouts compared to wild type cells, as revealed by GC/MS analysis. We also determined stress responses mediated by PAF-AH were related to proteins HEX1, Cu/Zn superoxide dismutase, and cytochrome c. Finally, PAF-AH exhibited antagonistic activity against Rhizoctonia solani in plate confrontation assays. Our results indicate PAF-AH may play an important role in T. harzianum stress response and antagonism under diverse environmental conditions.

  6. The JCMT Gould Belt Survey: Understanding the influence of outflows on Gould Belt clouds

    NASA Astrophysics Data System (ADS)

    Drabek-Maunder, E.; Hatchell, J.; Buckle, J. V.; Di Francesco, J.; Richer, J.

    2016-03-01

    Using James Clerk Maxwell Telescope (JCMT) Gould Belt Survey data from CO J = 3 → 2 isotopologues, we present a meta-analysis of the outflows and energetics of star-forming regions in several Gould Belt clouds. The majority of the regions are strongly gravitationally bound. There is evidence that molecular outflows transport large quantities of momentum and energy. Outflow energies are at least 20 per cent of the total turbulent kinetic energies in all of the regions studied and greater than the turbulent energy in half of the regions. However, we find no evidence that outflows increase levels of turbulence, and there is no correlation between the outflow and turbulent energies. Even though outflows in some regions contribute significantly to maintaining turbulence levels against dissipation, this relies on outflows efficiently coupling to bulk motions. Other mechanisms (e.g. supernovae) must be the main drivers of turbulence in most if not all of these regions.

  7. Emergence in China of human disease due to avian influenza A(H10N8)--cause for concern?

    PubMed

    To, Kelvin K W; Tsang, Alan K L; Chan, Jasper F W; Cheng, Vincent C C; Chen, Honglin; Yuen, Kwok-Yung

    2014-03-01

    In December 2013, China reported the first human case of avian influenza A(H10N8). A 73-year-old female with chronic diseases who had visited a live poultry market succumbed with community-acquired pneumonia. While human infections with avian influenza viruses are usually associated with subtypes prevalent in poultries, A(H10N8) isolates were mostly found in migratory birds and only recently in poultries. Although not possible to predict whether this single intrusion by A(H10N8) is an accident or the start of another epidemic like the preceding A(H7N9) and A(H5N1), several features suggest that A(H10N8) is a potential threat to humans. Recombinant H10 could attach to human respiratory epithelium, and A(H10N4) virus could cause severe infections in minks and chickens. A(H10N8) viruses contain genetic markers for mammalian adaptation and virulence in the haemagglutinin (A135T, S138A[H3 numbering]), M1(N30D, T215A), NS1(P42S) and PB2(E627K) protein. Studies on this human A(H10N8) isolate will reveal its adaptability to humans. Clinicians should alert the laboratory to test for A(H5,6,7,9,10) viruses in patients with epidemiological exposure in endemic geographical areas especially when human influenza A(H1,3) and B are negative. Vigilant virological and serological surveillance for A(H10N8) in human, poultry and wild bird is important for following the trajectory of this emerging influenza virus.

  8. Analysis of in situ measurements of cirrus anvil outflow dynamics

    NASA Astrophysics Data System (ADS)

    Lederman, J. I.; Whiteway, J. A.

    2012-12-01

    The airborne campaign, EMERALD 2 (Egrett Microphysics Experiment with Radiation, Lidar, and Dynamics,) was conducted out of Darwin, Australia in 2002. Objectives included characterization of the dynamics in the cirrus anvil outflow from tropical deep convection. Two aircraft, the Egrett and King Air, were flown in tandem in the upper troposphere (7 km - 15 km) to collect in situ measurements in the anvil outflow from a storm named "Hector" that occurs on a regular basis over the Tiwi Islands north of Darwin during November and December. Turbulence probes mounted on the wings of the Egrett aircraft were used to measure the wind fluctuations across the anvil and along its length with a spatial resolution of 2 meters. The in situ measurements from the Egrett were coincident with lidar measurements of the cloud structure from the King Air aircraft flying directly below. The presentation will show results of the analysis of the measurements with an emphasis on the turbulence, gravity waves, and coherent structures that are particular to the cirrus anvil outflow environment. Emphasis is placed on the dynamics associated with the generation of mammatus formations at the base of the anvil clouds.

  9. On the Structure of Accretion Disks with Outflows

    NASA Astrophysics Data System (ADS)

    Jiao, Cheng-Liang; Wu, Xue-Bing

    2011-06-01

    To study the outflows from accretion disks, we solve the set of hydrodynamic equations for accretion disks in spherical coordinates (rθphi) to obtain the explicit structure along the θ-direction. Using self-similar assumptions in the radial direction, we change the equations to a set of ordinary differential equations about the θ-coordinate, which are then solved with symmetrical boundary conditions in the equatorial plane; the velocity field is then obtained. The α viscosity prescription is applied and an advective factor f is used to simplify the energy equation. The results display thinner, quasi-Keplerian disks for Shakura-Sunyaev disks; thicker, sub-Keplerian disks for advection-dominated accretion flows; and slim disks which are consistent with previous popular analytical models. However, an inflow region and an outflow region always exist, except when the viscosity parameter α is too large, which supports the results of some recent numerical simulation works. Our results indicate that the outflows should be common in various accretion disks and may be stronger in slim disks, where both advection and radiation pressure are dominant. We also present the structure's dependence on the input parameters and discuss their physical meanings. The caveats of this work and possible improvements for the future are discussed.

  10. Massive Star Formation: Characterising Infall and Outflow in dense cores.

    NASA Astrophysics Data System (ADS)

    Akhter, Shaila; Cunningham, Maria; Harvey-Smith, Lisa; Jones, Paul Andrew; Purcell, Cormac; Walsh, Andrew John

    2015-08-01

    Massive stars are some of the most important objects in the Universe, shaping the evolution of galaxies, creating chemical elements, and hence shaping the evolution of the Universe. However, the processes by which they form, and how they shape their environment during their birth processes, are not well understood. We are using NH3 data from the "The H2O Southern Galactic Plane Survey" (HOPS) to define the positions of dense cores/clumps of gas in the southern Galactic plane that are likely to form stars. Due to its effective critical density, NH3 can detect massive star forming regions effectively compared to other tracers. We did a comparative study with different methods for finding clumps and found Fellwalker as the best. We found ~ 10% of the star forming clumps with multiple components and ~ 90% clumps with single component along the line of sight. Then, using data from the "The Millimetre Astronomy Legacy Team 90 GHz" (MALT90) survey, we search for the presence of infall and outflow associated with these cores. We will subsequently use the "3D Molecular Line Radiative Transfer Code" (MOLLIE) to constrain properties of the infall and outflow, such as velocity and mass flow. The aim of the project is to determine how common infall and outflow are in star forming cores, hence providing valuable constraints on the timescales and physical process involved in massive star formation.

  11. Ion Outflow At Mars Using MEX Ion And Electron Data

    NASA Astrophysics Data System (ADS)

    Fowler, Christopher M.; Andersson, L.; Lundin, R. N.; Frahm, R. A.

    2013-10-01

    How Mars lost it’s water and atmosphere is still an important question. Many studies have investigated high-energy ion fluxes (>10 eV) surrounding the planet and derived ion outflow rates in order to determine atmospheric loss. These rates suggest that the outflow from high-energy ions is not the dominant escape path for atmospheric loss. Over the years increasing evidence has indicated that the loss of low-energy ions is more important than the high-energy ion loss. In this presentation ion observations (down to the spacecraft potential) from the Mars Express (MEX) mission (2010/11), are used to describe the ion altitude distribution at Mars. The focus of this study is below the altitude of ~2000 km. Within the Mars environment, using the MEX electron observations different plasma regions were identified. Supported by electron identification, different altitude profiles of ion fluxes have been analyzed from the different plasma regions. The altitude profiles of the ion fluxes observed below the photoelectron boundary and in the sheath transition region in this study show large asymmetries between the northern and southern hemispheres. The ion distributions, resulting altitude profiles, the influence of the crustal magnetic field at Mars, and the implications relating to plasma outflow will be discussed in this presentation.

  12. A RECONNECTION-DRIVEN RAREFACTION WAVE MODEL FOR CORONAL OUTFLOWS

    SciTech Connect

    Bradshaw, S. J.; Aulanier, G.; Del Zanna, G.

    2011-12-10

    We conduct numerical experiments to determine whether interchange reconnection at high altitude coronal null points can explain the outflows observed as blueshifts in coronal emission lines at the boundaries between open and closed magnetic field regions. In this scenario, a strong, post-reconnection pressure gradient forms in the field-aligned direction when dense and hot, active region core loops reconnect with neighboring tenuous and cool, open field lines. We find that the pressure gradient drives a supersonic outflow and a rarefaction wave develops in both the open and closed post-reconnection magnetic field regions. We forward-model the spectral line profiles for a selection of coronal emission lines to predict the spectral signatures of the rarefaction wave. We find that the properties of the rarefaction wave are consistent with the observed velocity versus temperature structure of the corona in the outflow regions, where the velocity increases with the formation temperature of the emission lines. In particular, we find excellent agreement between the predicted and observed Fe XII 195.119 A spectral line profiles in terms of the blueshift (10 km s{sup -1}), full width at half-maximum (83 mA) and symmetry. Finally, we find that T{sub i} < T{sub e} in the open field region, which indicates that the interchange reconnection scenario may provide a viable mechanism and source region for the slow solar wind.

  13. Experimental constraints on the dynamics of martian outflow channels

    NASA Astrophysics Data System (ADS)

    Lenferink, H. J.; Perron, T.; Koss, A. R.

    2010-12-01

    Reconstructing the dynamics of the floods that carved the outflow channels on Mars is critical to understanding the erosive power and sediment transport capacity of the floods, and will place important constraints on Mars’ water inventory. We seek to constrain flood dynamics by studying the change in flow conditions at the transition from channel to plains. The distribution of streamlined islands records the lateral spreading of some of the largest floods as they exited confined channels at the dichotomy and advanced across the lowland plains. The rate of lateral spreading with distance beyond the end of the channel should be a function of the ratio of momentum sustaining the flow and drag forces impeding it. To define this relationship empirically, we conducted a set of laboratory experiments in which a turbulent suspension of fine sediment is released into a submerged channel in a still water tank and allowed to flow out of the channel and spread across a flat floor. We achieve Froude similarity with martian outflow channels by controlling the density contrast between the suspension and the ambient water. Varying flow density and velocity, we find that the spreading rate is positively correlated with a ratio of drag to momentum. When combined with measurements of the spreading rates of martian megafloods from a survey of streamlined islands, our experimental relationship yields estimates of the flow conditions at the downstream ends of the outflow channels. We compare this result with previous estimates of flood characteristics.

  14. Hot Jupiter breezes: time-dependent outflows from extrasolar planets

    NASA Astrophysics Data System (ADS)

    Owen, James E.; Adams, Fred C.

    2016-03-01

    We explore the dynamics of magnetically controlled outflows from hot Jupiters, where these flows are driven by UV heating from the central star. In these systems, some of the open field lines do not allow the flow to pass smoothly through the sonic point, so that steady-state solutions do not exist in general. This paper focuses on this type of magnetic field configuration, where the resulting flow becomes manifestly time-dependent. We consider the case of both steady heating and time-variable heating, and find the time-scales for the corresponding time variations of the outflow. Because the flow cannot pass through the sonic transition, it remains subsonic and leads to so-called breeze solutions. One manifestation of the time variability is that the flow samples a collection of different breeze solutions over time, and the mass outflow rate varies in quasi-periodic fashion. Because the flow is subsonic, information can propagate inwards from the outer boundary, which determines, in part, the time-scale of the flow variability. This work finds the relationship between the outer boundary scale and the time-scale of flow variations. In practice, the location of the outer boundary is set by the extent of the sphere of influence of the planet. The measured time variability can be used, in principle, to constrain the parameters of the system (e.g. the strengths of the surface magnetic fields).

  15. CLUSTERED STAR FORMATION AND OUTFLOWS IN AFGL 2591

    SciTech Connect

    Sanna, A.; Carrasco-Gonzalez, C.; Menten, K. M.; Brunthaler, A.; Reid, M. J.; Moscadelli, L.; Rygl, K. L. J.

    2012-02-01

    We report on a detailed study of the water maser kinematics and radio continuum emission toward the most massive and young object in the star-forming region AFGL 2591. Our analysis shows at least two spatial scales of multiple star formation, one projected across 0.1 pc on the sky and another one at about 2000 AU from a ZAMS star of about 38 M{sub Sun }. This young stellar object drives a powerful jet- and wind-driven outflow system with the water masers associated to the outflow walls, previously detected as a limb-brightened cavity in the NIR band. At about 1300 AU to the north of this object a younger protostar drives two bow shocks, outlined by arc-like water maser emission, at 200 AU either side of the source. We have traced the velocity profile of the gas that expands along these arc-like maser structures and compared it with the jet-driven outflow model. This analysis suggests that the ambient medium around the northern protostar is swept up by a jet-driven shock (>66 km s{sup -1}) and perhaps a lower-velocity ({approx}10 km s{sup -1}) wind with an opening angle of about 20 Degree-Sign from the jet axis.

  16. The role of superthermal electrons in high latitude ionospheric outflows

    NASA Astrophysics Data System (ADS)

    Glocer, A.; Khazanov, G. V.; Liemohn, M. W.; Toth, G.; Gombosi, T. I.

    2014-12-01

    It is well accepted that the ionosphere is a critical source of plasma for the magnetosphere, providing O+, H+, and He+ which can have wide ranging consequences for the space environment system. Changing ion composition affects magnetic reconnection in the magnetosphere, the ring current, and the wave environment which is important for high energy radiation belt electrons. Of the myriad of mechanisms that are important in determining the ionospheric outflow solution at high latitudes, we focus on the role of superthermal electron populations. It has been demonstrated in multiple studies that even small concentrations of superthermal electrons can have a dramatic effect on the outflow solution. In this presentation, we present simulation results using our Polar Wind Outflow Model (PWOM) and our SuperThermal Electron Transport (STET) code. We describe recent results on superthermal electrons role in defining the quiet time solar wind solution with comparisons to observations. We also discuss preliminary results that combine the PWOM and STET codes for a more comprehensive treatment of the impact of superthermal electrons.

  17. Physical Processes for Driving Ionospheric Outflows in Global Simulations

    NASA Technical Reports Server (NTRS)

    Moore, Thomas Earle; Strangeway, Robert J.

    2009-01-01

    We review and assess the importance of processes thought to drive ionospheric outflows, linking them as appropriate to the solar wind and interplanetary magnetic field, and to the spatial and temporal distribution of their magnetospheric internal responses. These begin with the diffuse effects of photoionization and thermal equilibrium of the ionospheric topside, enhancing Jeans' escape, with ambipolar diffusion and acceleration. Auroral outflows begin with dayside reconnexion and resultant field-aligned currents and driven convection. These produce plasmaspheric plumes, collisional heating and wave-particle interactions, centrifugal acceleration, and auroral acceleration by parallel electric fields, including enhanced ambipolar fields from electron heating by precipitating particles. Observations and simulations show that solar wind energy dissipation into the atmosphere is concentrated by the geomagnetic field into auroral regions with an amplification factor of 10-100, enhancing heavy species plasma and gas escape from gravity, and providing more current carrying capacity. Internal plasmas thus enable electromagnetic driving via coupling to the plasma, neutral gas and by extension, the entire body " We assess the Importance of each of these processes in terms of local escape flux production as well as global outflow, and suggest methods for their implementation within multispecies global simulation codes. We complete 'he survey with an assessment of outstanding obstacles to this objective.

  18. Spin properties of supermassive black holes with powerful outflows

    NASA Astrophysics Data System (ADS)

    Daly, Ruth. A.

    2016-05-01

    Relationships between beam power and accretion disc luminosity are studied for a sample of 55 high excitation radio galaxies (HERG), 13 low excitation radio galaxies (LERG), and 29 radio loud quasars (RLQ) with powerful outflows. The ratio of beam power to disc luminosity tends to be high for LERG, low for RLQ, and spans the full range of values for HERG. Writing general expressions for the disc luminosity and beam power and applying the empirically determined relationships allows a function that parametrizes the spins of the holes to be estimated. Interestingly, one of the solutions that is consistent with the data has a functional form that is remarkably similar to that expected in the generalized Blandford-Znajek model with a magnetic field that is similar in form to that expected in magnetically arrested disk (MAD) and advection-dominated accretion flow (ADAF) models. Values of the spin function, obtained independent of specific outflow models, suggest that spin and active galactic nucleus type are not related for these types of sources. The spin function can be used to solve for black hole spin in the context of particular outflow models, and one example is provided.

  19. Chemical and Aerosol Characteristics of Asian Outflow as Observed during INTEX-B and TRACE-P

    NASA Astrophysics Data System (ADS)

    Thornhill, L.; Anderson, B. E.; Winstead, E. L.; Chen, G.; Clarke, A.; Dibb, J.; Scheuer, E.; Sachse, G.; Blake, D.; Fuelberg, H.

    2007-12-01

    The NASA Intercontinental Transport and Chemistry Experiment, phase B (INTEX-B) was conducted in the spring of 2006 to investigate the transport and transformation of gases and aerosols on transcontinental/intercontinental scales and to assess the impacts of the aged pollutants on air quality and climate. To accomplish these goals, the instrumented, North Dakota DC-8 aircraft was deployed during two separate phases to study vastly different pollution and transport phenomena. During the first 3 weeks of March, the aircraft was based in Houston and flew sorties over Mexico City and the western Gulf to examine the composition, outflow pathways, and evolution of pollution from Mexico City. The second phase took place between April 17 and May 15, and involved basing the aircraft at first Hickam AFB, Hawaii, then Anchorage, AK to examine the outflow of pollution from Asia at different points along the transport pathway. In this presentation, we analyze data from the second phase of INTEX-B to characterize the composition of Asian outflow as a function of age (e.g. C2H2/CO ratio) and vertical location (0-2, 2-4, 4-6, 6-8, and >8 km). We use airmass trajectories to identify the primary Asian continental source regions that influence atmospheric composition within the Northeast Pacific region and characterize those source regions using aerosol and gas phase tracers. In addition, we compare INTEX-B vertical profiles of trace gas and aerosol species with similar measurements recorded aboard the DC-8 just off the Asian coast during the 2001 NASA Transport and Chemistry near the Equator - Pacific (TRACE-P) experiment to evaluate changes in species concentrations/characteristics during the approximately 10-day transport period between the two regions.

  20. AhR-dependent secretion of PDGF-BB by human classically activated macrophages exposed to DEP extracts stimulates lung fibroblast proliferation

    SciTech Connect

    Jaguin, Marie; Fardel, Olivier; Lecureur, Valérie

    2015-06-15

    Lung diseases are aggravated by exposure to diesel exhaust particles (DEPs) found in air pollution. Macrophages are thought to play a crucial role in lung immune response to these pollutants, even if the mechanisms involved remain incompletely characterized. In the present study, we demonstrated that classically and alternative human macrophages (MΦ) exhibited increased secretion of PDGF-B in response to DEP extract (DEPe). This occurred via aryl hydrocarbon receptor (AhR)-activation because DEPe-induced PDGF-B overexpression was abrogated after AhR expression knock-down by RNA interference, in both M1 and M2 polarizing MΦ. In addition, TCDD and benzo(a)pyrene, two potent AhR ligands, also significantly increased mRNA expression of PDGF-B in M1 MΦ, whereas some weak ligands of AhR did not. We next evaluated the impact of conditioned media (CM) from MΦ culture exposed to DEPe or of recombinant PDGF-B onto lung fibroblast proliferation. The tyrosine kinase inhibitor, AG-1295, prevents phosphorylations of PDGF-Rβ, AKT and ERK1/2 and the proliferation of MRC-5 fibroblasts induced by recombinant PDGF-B and by CM from M1 polarizing MΦ, strongly suggesting that the PDGF-BB secreted by DEPe-exposed MΦ is sufficient to activate the PDGF-Rβ pathway of human lung fibroblasts. In conclusion, we demonstrated that human MΦ, whatever their polarization status, secrete PDGF-B in response to DEPe and that PDGF-B is a target gene of AhR. Therefore, induction of PDGF-B by DEP may participate in the deleterious effects towards human health triggered by such environmental urban contaminants. - Highlights: • PDGF-B expression and secretion are increased by DEPe exposure in human M1 and M2 MΦ. • DEPe-induced PDGF-B expression is aryl-hydrocarbon-dependent. • DEPe-exposed M1 MΦ secrete sufficient PDGF-B to increase lung fibroblast proliferation.

  1. Summary of AH-1G flight vibration data for validation of coupled rotor-fuselage analyses

    NASA Technical Reports Server (NTRS)

    Dompka, R. V.; Cronkhite, J. D.

    1986-01-01

    Under a NASA research program designated DAMVIBS (Design Analysis Methods for VIBrationS), four U. S. helicopter industry participants (Bell Helicopter, Boeing Vertol, McDonnell Douglas Helicopter, and Sikorsky Aircraft) are to apply existing analytical methods for calculating coupled rotor-fuselage vibrations of the AH-1G helicopter for correlation with flight test data from an AH-1G Operational Load Survey (OLS) test program. Bell Helicopter, as the manufacturer of the AH-1G, was asked to provide pertinent rotor data and to collect the OLS flight vibration data needed to perform the correlations. The analytical representation of the fuselage structure is based on a NASTRAN finite element model (FEM) developed by Bell which has been extensively documented and correlated with ground vibration tests.The AH-1G FEM was provided to each of the participants for use in their coupled rotor-fuselage analyses. This report describes the AH-1G OLS flight test program and provides the flight conditions and measured vibration data to be used by each participant in their correlation effort. In addition, the mechanical, structural, inertial and aerodynamic data for the AH-1G two-bladed teetering main rotor system are presented. Furthermore, modifications to the NASTRAN FEM of the fuselage structure that are necessary to make it compatible with the OLS test article are described. The AH-1G OLS flight test data was found to be well documented and provide a sound basis for evaluating currently existing analysis methods used for calculation of coupled rotor-fuselage vibrations.

  2. Phylodynamics of influenza A(H3N2) in South America, 1999-2012.

    PubMed

    Born, Priscila Silva; Siqueira, Marilda Mendonça; Faria, Nuno Rodrigues; Resende, Paola Cristina; Motta, Fernando Couto; Bello, Gonzalo

    2016-09-01

    The limited influenza A(H3N2) genetic data available from the Southern Hemisphere (particularly from Africa and Latin America), constrains the accurate reconstruction of viral dissemination dynamics within those regions. Our objective was to describe the spatial dissemination dynamics of influenza A(H3N2) within South America. A total of 469 sequences of the HA1 portion of the hemagglutinin gene (HA) from influenza A(H3N2) viruses sampled in temperate and tropical South American countries between 1999 and 2012 were combined with available contemporary sequences from Australia, Hong Kong, United Kingdom and the United States. Phylogenetic analyses revealed that influenza A(H3N2) sequences from South America were highly intermixed with sequences from other geographical regions, although a clear geographic virus population structure was detected globally. We identified 14 clades mostly (≥80%) composed of influenza sequences from South American countries. Bayesian phylogeographic analyses of those clades support a significant role of both temperate and tropical regions in the introduction and dissemination of new influenza A(H3N2) strains within South America and identify an intensive bidirectional viral exchange between different geographical areas. These findings indicate that seasonal influenza A(H3N2) epidemics in South America are seeded by both the continuous importation of viral variants from other geographic regions and the short-term persistence of local lineages. This study also supports a complex metapopulation model of influenza A(H3N2) dissemination in South America, with no preferential direction in viral movement between temperate and tropical regions. PMID:27275847

  3. The Phenomenology of Outflows from Radio Loud Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Guerra, Erick Jimenez

    This thesis presents the results of two studies involving collimated outflows in radio loud active galactic nuclei (AGN). The first study examines relativistic outflows from the cores of different classes of AGN, and estimates of bulk Lorentz factors and viewing angles. The second study deals with powerful extended radio galaxies, the relation between their lifetime and their luminosity in directed kinetic energy, or beam power, and the use of these sources for cosmology. Compact radio sources are examined, and the kinematics of their outflows are determined. Two updated sets of Doppler factor estimates, one using the equipartition method and the other using the inverse Compton method, for 100 radio cores are discussed. Intrinsic brightness temperatures based on these Doppler factors are examined along with their relevance to the 'inverse Compton catastrophe'. Intrinsic luminosity densities and luminosities are presented, and the role of systematic errors is discussed. Outflow angles and bulk Lorentz factors are computed for 43 out of the 100 sources on the basis of proper motions compiled by Vermeulen & Cohen (1994). These estimates of outflow angles and bulk Lorentz factors are discussed along with their agreement with orientation unified models of AGN. Powerful extended radio galaxies are examined, and the relation between the active lifetime and the beam power in these sources is investigated by comparing the redshift evolution of characteristic source size to the redshift evolution of the average lobe-lobe size. It is found that the data are described by a model in which the active lifetime of the source, t/*, is written as a power-law in the beam power, Lj. The exponent of the power law is estimated to be βsimeq2.1±0.6, where t/*∝ Lj-β/3, which excludes β=0, an Eddington-limited system. The same comparison of characteristic source sizes to the average lobe-lobe size can be used to constrain cosmological parameters. The data indicate a low value of

  4. Impacts of pure shocks in the BHR71 bipolar outflow

    NASA Astrophysics Data System (ADS)

    Gusdorf, A.; Riquelme, D.; Anderl, S.; Eislöffel, J.; Codella, C.; Gómez-Ruiz, A. I.; Graf, U. U.; Kristensen, L. E.; Leurini, S.; Parise, B.; Requena-Torres, M. A.; Ricken, O.; Güsten, R.

    2015-03-01

    Context. During the formation of a star, material is ejected along powerful jets that impact the ambient material. This outflow regulates star formation by e.g. inducing turbulence and heating the surrounding gas. Understanding the associated shocks is therefore essential to the study of star formation. Aims: We present comparisons of shock models with CO, H2, and SiO observations in a "pure" shock position in the BHR71 bipolar outflow. These comparisons provide an insight into the shock and pre-shock characteristics, and allow us to understand the energetic and chemical feedback of star formation on Galactic scales. Methods: New CO (Jup = 16, 11, 7, 6, 4, 3) observations from the shocked regions with the SOFIA and APEX telescopes are presented and combined with earlier H2 and SiO data (from the Spitzer and APEX telescopes). The integrated intensities are compared to a grid of models that were obtained from a magneto-hydrodynamical shock code, which calculates the dynamical and chemical structure of these regions combined with a radiative transfer module based on the "large velocity gradient" approximation. Results: The CO emission leads us to update the conclusions of our previous shock analysis: pre-shock densities of 104 cm-3 and shock velocities around 20-25 km s-1 are still constrained, but older ages are inferred (~4000 years). Conclusions: We evaluate the contribution of shocks to the excitation of CO around forming stars. The SiO observations are compatible with a scenario where less than 4% of the pre-shock SiO belongs to the grain mantles. We infer outflow parameters: a mass of 1.8 × 10-2 M⊙ was measured in our beam, in which a momentum of 0.4 M⊙ km s-1 is dissipated, corresponding to an energy of 4.2 × 1043 erg. We analyse the energetics of the outflow species by species. Comparing our results with previous studies highlights their dependence on the method: H2 observations only are not sufficient to evaluate the mass of outflows.

  5. Genome-Wide Analysis of Evolutionary Markers of Human Influenza A(H1N1)pdm09 and A(H3N2) Viruses May Guide Selection of Vaccine Strain Candidates

    PubMed Central

    Belanov, Sergei S.; Bychkov, Dmitrii; Benner, Christian; Ripatti, Samuli; Ojala, Teija; Kankainen, Matti; Kai Lee, Hong; Wei-Tze Tang, Julian; Kainov, Denis E.

    2015-01-01

    Here we analyzed whole-genome sequences of 3,969 influenza A(H1N1)pdm09 and 4,774 A(H3N2) strains that circulated during 2009–2015 in the world. The analysis revealed changes at 481 and 533 amino acid sites in proteins of influenza A(H1N1)pdm09 and A(H3N2) strains, respectively. Many of these changes were introduced as a result of random drift. However, there were 61 and 68 changes that were present in relatively large number of A(H1N1)pdm09 and A(H3N2) strains, respectively, that circulated during relatively long time. We named these amino acid substitutions evolutionary markers, as they seemed to contain valuable information regarding the viral evolution. Interestingly, influenza A(H1N1)pdm09 and A(H3N2) viruses acquired non-overlapping sets of evolutionary markers. We next analyzed these characteristic markers in vaccine strains recommended by the World Health Organization for the past five years. Our analysis revealed that vaccine strains carried only few evolutionary markers at antigenic sites of viral hemagglutinin (HA) and neuraminidase (NA). The absence of these markers at antigenic sites could affect the recognition of HA and NA by human antibodies generated in response to vaccinations. This could, in part, explain moderate efficacy of influenza vaccines during 2009–2014. Finally, we identified influenza A(H1N1)pdm09 and A(H3N2) strains, which contain all the evolutionary markers of influenza A strains circulated in 2015, and which could be used as vaccine candidates for the 2015/2016 season. Thus, genome-wide analysis of evolutionary markers of influenza A(H1N1)pdm09 and A(H3N2) viruses may guide selection of vaccine strain candidates. PMID:26615216

  6. Genome-Wide Analysis of Evolutionary Markers of Human Influenza A(H1N1)pdm09 and A(H3N2) Viruses May Guide Selection of Vaccine Strain Candidates.

    PubMed

    Belanov, Sergei S; Bychkov, Dmitrii; Benner, Christian; Ripatti, Samuli; Ojala, Teija; Kankainen, Matti; Kai Lee, Hong; Wei-Tze Tang, Julian; Kainov, Denis E

    2015-11-27

    Here we analyzed whole-genome sequences of 3,969 influenza A(H1N1)pdm09 and 4,774 A(H3N2) strains that circulated during 2009-2015 in the world. The analysis revealed changes at 481 and 533 amino acid sites in proteins of influenza A(H1N1)pdm09 and A(H3N2) strains, respectively. Many of these changes were introduced as a result of random drift. However, there were 61 and 68 changes that were present in relatively large number of A(H1N1)pdm09 and A(H3N2) strains, respectively, that circulated during relatively long time. We named these amino acid substitutions evolutionary markers, as they seemed to contain valuable information regarding the viral evolution. Interestingly, influenza A(H1N1)pdm09 and A(H3N2) viruses acquired non-overlapping sets of evolutionary markers. We next analyzed these characteristic markers in vaccine strains recommended by the World Health Organization for the past five years. Our analysis revealed that vaccine strains carried only few evolutionary markers at antigenic sites of viral hemagglutinin (HA) and neuraminidase (NA). The absence of these markers at antigenic sites could affect the recognition of HA and NA by human antibodies generated in response to vaccinations. This could, in part, explain moderate efficacy of influenza vaccines during 2009-2014. Finally, we identified influenza A(H1N1)pdm09 and A(H3N2) strains, which contain all the evolutionary markers of influenza A strains circulated in 2015, and which could be used as vaccine candidates for the 2015/2016 season. Thus, genome-wide analysis of evolutionary markers of influenza A(H1N1)pdm09 and A(H3N2) viruses may guide selection of vaccine strain candidates.

  7. Developing the Next Generation of Tools for Simulating Galaxy Outflows

    NASA Astrophysics Data System (ADS)

    Scannapieco, Evan

    Outflows are observed in starbursting galaxies of all masses and at all cosmological epochs. They play a key role throughout the history of the Universe: shaping the galaxy mass-metallicity relation, drastically affecting the content and number density of dwarf galaxies, and transforming the chemical composition of the intergalactic medium. Yet, a complete model of galaxy out ows has proven to be elusive, as it requires both a better understanding of the evolution of the turbulent, multiphase gas in and around starbursting galaxies, and better tools to reproduce this evolution in galaxy-scale simulations. Here we propose to conduct a detailed series of numerical simulations designed to help develop such next-generation tools for the simulation of galaxy outflows. The program will consist of three types of direct numerical simulations, each of which will be targeted to allow galaxy-scale simulations to more accurately model key microphysical processes and their observational consequences. Our first set of simulations will be targeted at better modeling the starbursting interstellar medium (ISM) from which galaxy outflows are driven. The surface densities in starbursting galaxies are much larger than those in the Milky Way, resulting in larger gravitational accelerations and random velocities exceeding 30 or even 100 km/s. Under these conditions, the thermal stability of the ISM is changed dramatically, due to the sharp peak in gas cooling efficiency at H 200,000 K. Our simulations will carefully quantify the key ways in which this medium differs from the local ISM, and the consequences of these differences for when, where, and how outflows are driven. A second set of simulations will be targeted at better modeling the observed properties of rapidly cooling, highly turbulent gas. Because gas cooling in and around starbursts is extremely efficient, turbulent motions are often supersonic, which leads to a distribution of ionization states that is vastly different than

  8. The impact of flow-induced forces on the morphogenesis of the outflow tract

    PubMed Central

    Biechler, Stefanie V.; Junor, Lorain; Evans, Ashlie N.; Eberth, John F.; Price, Robert L.; Potts, Jay D.; Yost, Michael J.; Goodwin, Richard L.

    2014-01-01

    One percent of infants are born with congenital heart disease (CHD), which commonly involves outflow tract (OFT) defects. These infants often require complex surgeries, which are associated with long term adverse remodeling effects, and receive replacement valves with limited strength, biocompatibility, and growth capability. To address these problematic issues, researchers have carried out investigations in valve development and valve mechanics. A longstanding hypothesis is that flow-induced forces regulate fibrous valve development, however, the specific mechanisms behind this mechanotransduction remain unclear. The purpose of this study was to implement an in vitro system of outflow tract development to test the response of embryonic OFT tissues to fluid flow. A dynamic, three-dimensional bioreactor system was used to culture embryonic OFT tissue under different levels of flow as well as the absence of flow. In the absence of flow, OFT tissues took on a more primitive phenotype that is characteristic of early OFT cushion development where widely dispersed mesenchymal cells are surrounded by a sparse, disorganized extracellular matrix (ECM). Whereas OFT tissues subjected to physiologically matched flow formed compact mounds of cells, initated, fibrous ECM development, while prolonged supraphysiological flow resulted in abnormal tissue remodeling. This study indicates that both the timing and magnitude of flow alter cellular processes that determine if OFT precursor tissue undergoes normal or pathological development. Specifically, these experiments showed that flow-generated forces regulate the deposition and localization of fibrous ECM proteins, indicating that mechanosensitive signaling pathways are capable of driving pathological OFT development if flows are not ideal. PMID:24987377

  9. Frs2α-deficiency in cardiac progenitors disrupts a subset of FGF signals required for outflow tract morphogenesis

    PubMed Central

    Zhang, Jue; Lin, Yongshun; Zhang, Yongyou; Lan, Yongsheng; Lin, Chunhong; Moon, Anne M.; Schwartz, Robert J.; Martin, James F.; Wang, Fen

    2009-01-01

    Summary The cardiac outflow tract (OFT) is a developmentally complex structure derived from multiple lineages and is often defective in human congenital anomalies. While emerging evidence shows that the fibroblast growth factor (FGF) is essential for OFT development, the downstream pathways mediating FGF-signaling in cardiac progenitors remain poorly understood. Here, we report that FRS2α, an adaptor protein that links FGF receptor kinases to multiple signaling pathways, mediates critical aspects of FGF-dependent OFT development. Ablation of Frs2α in mesodermal OFT progenitor cells that originate in the second heart field (SHF) affects their expansion into the OFT myocardium, resulting in OFT misalignment and hypoplasia. Moreover, Frs2α mutants had defective endothelial-mesenchymal-transition and neural crest cell recruitment into the OFT cushions, resulting in OFT septation defects. The results provide new insight into the signaling molecules downstream of FGF receptor tyrosine kinases in cardiac progenitors. PMID:18832393

  10. International Laboratory Comparison of Influenza Microneutralization Assays for A(H1N1)pdm09, A(H3N2), and A(H5N1) Influenza Viruses by CONSISE.

    PubMed

    Laurie, Karen L; Engelhardt, Othmar G; Wood, John; Heath, Alan; Katz, Jacqueline M; Peiris, Malik; Hoschler, Katja; Hungnes, Olav; Zhang, Wenqing; Van Kerkhove, Maria D

    2015-08-01

    The microneutralization assay is commonly used to detect antibodies to influenza virus, and multiple protocols are used worldwide. These protocols differ in the incubation time of the assay as well as in the order of specific steps, and even within protocols there are often further adjustments in individual laboratories. The impact these protocol variations have on influenza serology data is unclear. Thus, a laboratory comparison of the 2-day enzyme-linked immunosorbent assay (ELISA) and 3-day hemagglutination (HA) microneutralization (MN) protocols, using A(H1N1)pdm09, A(H3N2), and A(H5N1) viruses, was performed by the CONSISE Laboratory Working Group. Individual laboratories performed both assay protocols, on multiple occasions, using different serum panels. Thirteen laboratories from around the world participated. Within each laboratory, serum sample titers for the different assay protocols were compared between assays to determine the sensitivity of each assay and were compared between replicates to assess the reproducibility of each protocol for each laboratory. There was good correlation of the results obtained using the two assay protocols in most laboratories, indicating that these assays may be interchangeable for detecting antibodies to the influenza A viruses included in this study. Importantly, participating laboratories have aligned their methodologies to the CONSISE consensus 2-day ELISA and 3-day HA MN assay protocols to enable better correlation of these assays in the future.

  11. Studies on the role of the Ah receptor in hexachloro-benzene-induced porphyria

    SciTech Connect

    Hahn, M.E.

    1987-01-01

    Many of the effects of hexachlorobenzene (HCB) resemble those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), whose effects are initiated by its binding to the AH receptor, the regulatory gene product of the Ah locus. I investigated the ability of HCB to interact with the AH receptor and the involvement of this protein in HCB-induced porphyria. The induction of two cytochrome P450 isozymes regulated by the Ah locus was also examined in light of their possible role in the pathogenesis of HCB- and TCDD-induced porphyria. HCB competitively inhibited the in vitro specific binding of ({sup 3}H)-TCDD to the rat hepatic Ah receptor (K{sub I} = 2.1 {mu}M) without affecting the solubility of ({sup 3}H)TCDD. Following the administration of HCB to rats, the number of ({sup 3}H)TCDD specific binding sites was reduced by up to 40%. HCB induced cytochromes P450b, P450e, P450c, and P450d, confirming that it is a mixed-type P450 inducer. The presence of porphyria in mice was assessed by measuring urinary and hepatic porphyrins and hepatic uroporphyrinogen decarboxylase activity.

  12. Airborne Transmission of Influenza A/H5N1 Virus Between Ferrets

    PubMed Central

    Herfst, Sander; Schrauwen, Eefje J. A.; Linster, Martin; Chutinimitkul, Salin; de Wit, Emmie; Munster, Vincent J.; Sorrell, Erin M.; Bestebroer, Theo M.; Burke, David F.; Smith, Derek J.; Rimmelzwaan, Guus F.; Osterhaus, Albert D. M. E.; Fouchier, Ron A. M.

    2016-01-01

    Highly pathogenic avian influenza A/H5N1 virus can cause morbidity and mortality in humans but thus far has not acquired the ability to be transmitted by aerosol or respiratory droplet (“airborne transmission”) between humans. To address the concern that the virus could acquire this ability under natural conditions, we genetically modified A/H5N1 virus by site-directed mutagenesis and subsequent serial passage in ferrets. The genetically modified A/H5N1 virus acquired mutations during passage in ferrets, ultimately becoming airborne transmissible in ferrets. None of the recipient ferrets died after airborne infection with the mutant A/H5N1 viruses. Four amino acid substitutions in the host receptor-binding protein hemagglutinin, and one in the polymerase complex protein basic polymerase 2, were consistently present in airborne-transmitted viruses. The transmissible viruses were sensitive to the antiviral drug oseltamivir and reacted well with antisera raised against H5 influenza vaccine strains. Thus, avian A/H5N1 influenza viruses can acquire the capacity for airborne transmission between mammals without recombination in an intermediate host and therefore constitute a risk for human pandemic influenza. PMID:22723413

  13. Long-Term Cytotoxicity, pH and Dissolution Rate of AH Plus and MTA Fillapex.

    PubMed

    Silva, Emmanuel João Nogueira Leal da; Accorsi-Mendonça, Thais; Pedrosa, Ana Carolina; Granjeiro, José Mauro; Zaia, Alexandre A

    2016-01-01

    The aim of the present study was to verify the long-term cytotoxic effects of the MTA Fillapex and to compare them with AH Plus. Dissolution rate and pH were also evaluated. Human osteoblast cells were incubated with elutes of fresh specimens from AH Plus and MTA Fillapex, and with elutes of the same specimens for 4 successive weeks. Elute's pH was evaluated at each time point. A multiparametric cell viability assay was performed. For dissolution rate, ISO methodology was used. The results were analyzed by one-way analysis of variance, complemented with the Tukey post-test (p<0.05). No significant difference was found among the materials when fresh mixed (p>0.05). After 1 week, AH Plus became non-cytotoxic on all three evaluated parameters. Conversely, MTA Fillapex remained severely and mildly cytotoxic over the entire experimental period (p<0.05). The dissolution rate of AH Plus was significantly lower than MTA Fillapex at all time points (p>0.05). The pH of AH Plus was significantly lower than MTA Fillapex at the second and third week (p<0.05). In the other tested time points no statistical difference was observed. In conclusion, MTA Fillapex remained cytotoxic after 4 weeks and its cytotoxicity may be related to the high dissolution rate of this material. PMID:27652704

  14. Effects of scorched food leachates with or without activated charcoal pretreatment on AhR activation in cultured cells.

    PubMed

    Takahashi, Satoshi; Morita, Koji; Kinoshita, Makoto; Fujimori, Shin; Ishikawa, Toshio

    2015-12-01

    Aryl hydrocarbon receptor (AhR) is a transcription factor activated by xenobiotics, including dioxins and polycyclic aromatic hydrocarbons (PAHs). Although AhR is also activated by some dietary constituents, it has not been completely clarified in what circumstances AhR ligands are ingested in our daily life. Because PAHs are formed by the incomplete combustion of organic materials, we hypothesized that scorched foods might contain and leach out AhR ligands sufficient to stimulate AhR in vitro. To test this hypothesis, scorched foods (bread, cheese, etc.) were mixed vigorously with water, and the supernatants were retrieved as samples. The samples were added to HepG2 cells stably expressing an AhR-responsive reporter gene. Also, expression of CYP1A1, an endogenous AhR-responsive gene, was analyzed by RT-PCR in different cell lines treated with the samples. We further tested whether pretreatment of the samples with activated charcoal would alter their AhR-stimulating activity. All the supernatant samples tested induced AhR-dependent reporter gene activity and CYP1A1 mRNA expression. In some samples, these inductions were inhibited by pretreatment with activated charcoal. Our findings indicate that scorched food leachates stimulate AhR in cultured cells and that activated charcoal adsorbs the AhR-stimulating substances in some leachates. Thus, people who habitually eat scorched foods are exposed to AhR ligands on a regular basis. Further studies are needed to elucidate whether burnt foods actually exert biological effects on our health.

  15. Effects of scorched food leachates with or without activated charcoal pretreatment on AhR activation in cultured cells.

    PubMed

    Takahashi, Satoshi; Morita, Koji; Kinoshita, Makoto; Fujimori, Shin; Ishikawa, Toshio

    2015-12-01

    Aryl hydrocarbon receptor (AhR) is a transcription factor activated by xenobiotics, including dioxins and polycyclic aromatic hydrocarbons (PAHs). Although AhR is also activated by some dietary constituents, it has not been completely clarified in what circumstances AhR ligands are ingested in our daily life. Because PAHs are formed by the incomplete combustion of organic materials, we hypothesized that scorched foods might contain and leach out AhR ligands sufficient to stimulate AhR in vitro. To test this hypothesis, scorched foods (bread, cheese, etc.) were mixed vigorously with water, and the supernatants were retrieved as samples. The samples were added to HepG2 cells stably expressing an AhR-responsive reporter gene. Also, expression of CYP1A1, an endogenous AhR-responsive gene, was analyzed by RT-PCR in different cell lines treated with the samples. We further tested whether pretreatment of the samples with activated charcoal would alter their AhR-stimulating activity. All the supernatant samples tested induced AhR-dependent reporter gene activity and CYP1A1 mRNA expression. In some samples, these inductions were inhibited by pretreatment with activated charcoal. Our findings indicate that scorched food leachates stimulate AhR in cultured cells and that activated charcoal adsorbs the AhR-stimulating substances in some leachates. Thus, people who habitually eat scorched foods are exposed to AhR ligands on a regular basis. Further studies are needed to elucidate whether burnt foods actually exert biological effects on our health. PMID:26558458

  16. A human intervention study with foods containing natural Ah-receptor agonists does not significantly show AhR-mediated effects as measured in blood cells and urine.

    PubMed

    de Waard, Pim W J; Peijnenburg, Ad A C M; Baykus, Hakan; Aarts, Jac M M J G; Hoogenboom, Ron L A P; van Schooten, Frederik J; de Kok, Theo M C M

    2008-10-22

    Binding and activation of the aryl hydrocarbon receptor (AhR) is thought to be an essential step in the toxicity of the environmental pollutants dioxins and dioxin-like PCBs. However, also a number of natural compounds, referred to as NAhRAs (natural Ah-receptor agonists), which are present in, for example, fruits and vegetables, can bind and activate this receptor. To study their potential effects in humans, we first investigated the effect of the prototypical AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gene expression in ex vivo exposed freshly isolated human lymphocytes, and compared the resulting gene expression profile with those caused by the well-known NAhRA indolo[3,2-b]carbazole (ICZ), originating from cruciferous vegetables, and by a hexane extract of NAhRA-containing grapefruit juice (GJE). Only ICZ induced a gene expression profile similar to TCDD in the lymphocytes, and both significantly up-regulated CYP1B1 and TIPARP (TCDD-inducible poly (ADP-ribose) polymerase) mRNA. Next, we performed a human intervention study with NAhRA-containing cruciferous vegetables and grapefruit juice. The expression of the prototypical AhR-responsive genes CYP1A1, CYP1B1 and NQO1 in whole blood cells and in freshly isolated lymphocytes was not significantly affected. Also enzyme activities of CYP1A2, CYP2A6, N-acetyltransferase 2 (NAT2) and xanthine oxidase (XO), as judged by caffeine metabolites in urine, were unaffected, except for a small down-regulation of NAT2 activity by grapefruit juice. Examination of blood plasma with DR CALUX showed a 12% increased AhR agonist activity 3 and 24 h after consumption of cruciferous vegetables, but did not show a significant effect of grapefruit juice consumption. We conclude that intake of NAhRAs from food may result in minor AhR-related effects measurable in human blood and urine. PMID:18762178

  17. Visualization of conventional outflow tissue responses to netarsudil in living mouse eyes.

    PubMed

    Li, Guorong; Mukherjee, Dibyendu; Navarro, Iris; Ashpole, Nicole E; Sherwood, Joseph M; Chang, Jinlong; Overby, Darryl R; Yuan, Fan; Gonzalez, Pedro; Kopczynski, Casey C; Farsiu, Sina; Stamer, W Daniel

    2016-09-15

    Visual impairment due to glaucoma currently impacts 70 million people worldwide. While disease progression can be slowed or stopped with effective lowering of intraocular pressure, current medical treatments are often inadequate. Fortunately, three new classes of therapeutics that target the diseased conventional outflow tissue responsible for ocular hypertension are in the final stages of human testing. The rho kinase inhibitors have proven particularly efficacious and additive to current therapies. Unfortunately, non-contact technology that monitors the health of outflow tissue and its response to conventional outflow therapy is not available clinically. Using optical coherence tomographic (OCT) imaging and novel segmentation software, we present the first demonstration of drug effects on conventional outflow tissues in living eyes. Topical netarsudil (formerly AR-13324), a rho kinase/ norepinephrine transporter inhibitor, affected both proximal (trabecular meshwork and Schlemm's Canal) and distal portions (intrascleral vessels) of the mouse conventional outflow tract. Hence, increased perfusion of outflow tissues was reliably resolved by OCT as widening of the trabecular meshwork and significant increases in cross-sectional area of Schlemm's canal following netarsudil treatment. These changes occurred in conjunction with increased outflow facility, increased speckle variance intensity of outflow vessels, increased tracer deposition in conventional outflow tissues and decreased intraocular pressure. This is the first report using live imaging to show real-time drug effects on conventional outflow tissues and specifically the mechanism of action of netarsudil in mouse eyes. Advancements here pave the way for development of a clinic-friendly OCT platform for monitoring glaucoma therapy. PMID:27085895

  18. Uncovering the Outflow Driven by the Brown Dwarf LS-RCrA 1: Hα as a Tracer of Outflow Activity in Brown Dwarfs

    NASA Astrophysics Data System (ADS)

    Whelan, E. T.; Ray, T. P.; Bacciotti, F.

    2009-02-01

    It is now apparent that classical T Tauri-like outflows commonly accompany the formation of young brown dwarfs (BDs). To date two optical outflows have been discovered, and results presented in this Letter increase this number to three. Using spectro-astrometry, the origin of the LS-RCrA 1 forbidden emission lines in a blueshifted outflow is confirmed. The nondetection of the redshifted component of the outflow in forbidden lines, along with evidence for some separation between low- and high-velocity outflow components, does not support the hypothesis that LS-RCrA 1 has an edge-on accretion disk. The key result of this analysis is the discovery of an outflow component to the Hα line. The Hα line profile has blueshifted and redshifted features in the wings which spectro-astrometry reveals to also originate in the outflow. The discovery that Hα emission in BDs can have a significant contribution from an outflow suggests that the use of Hα line widths as a proxy of mass accretion in BDs is not clear cut. This method assumes that any contribution to the Hα line flux from a possible outflow is negligible. Finally, the fact that the Hα line traces both lobes of the outflow while only the blueshifted lobe is seen in forbidden emission points to the presence of a dust hole in the accretion disk of LS-RCrA 1. This is commonly seen in classical T Tauri stars and is assumed to signal the onset of planet formation. Based on data collected by UVES observations (observing runs 67.C-0549(B), 69.B-0126(A), 71.C-0429(C), and 71.C-0429(D)) at the VLT on Cerro Paranal (Chile) which is operated by the European Southern Observatory (ESO).

  19. AhR expression and polymorphisms are associated with risk of coronary arterial disease in Chinese population

    PubMed Central

    Huang, Shian; Shui, Xiaorong; He, Yuan; Xue, Yiqiang; Li, Jianwen; Li, Guoming; Lei, Wei; Chen, Can

    2015-01-01

    The aryl hydrocarbon receptor (AhR) mediates the control of environmental toxicity, and modulates the development and pathogenesis of the cardiovascular system. However, little is known about the role of AhR in coronary arterial disease (CAD) susceptibility. We therefore conducted a case-control study in a Chinese population, and assessed the potential association between AhR variants and CAD susceptibility. Compared with the controls, circulating AhR expression was found to be significantly increased in patients with CAD and its subtypes including ST-segment and non-ST-segment elevation myocardial infarction, and stable and unstable angina pectoris. Receiver operating characteristic (ROC) analysis to evaluate the effect of AhR on CAD progression showed it to be a potent biomarker for CAD. Genotype frequencies of AhR rs2066853 differed significantly between CAD and control subjects, while smoking and hyperlipidemia markedly promoted CAD risk relative to the AhR polymorphism. Moreover, a significant difference in AhR variant distribution was observed between the four CAD subtypes with different severities. The expression level and functional polymorphisms of circulating AhR may affect the susceptibility and progression of CAD in Chinese populations. This provides a novel view of the etiology and epidemiology of CAD, and will contribute to the diagnosis and therapy of this severe disease. PMID:25620626

  20. Physicochemical properties and surfaces morphologies evaluation of MTA FillApex and AH plus.

    PubMed

    Borges, Álvaro Henrique; Orçati Dorileo, Maura Cristiane Gonçales; Dalla Villa, Ricardo; Borba, Alexandre Meireles; Semenoff, Tereza Aparecida Delle Vedove; Guedes, Orlando Aguirre; Estrela, Cyntia Rodrigues Araújo; Bandeca, Matheus Coelho

    2014-01-01

    The solubility, pH, electrical conductivity, and radiopacity of AH Plus and MTA FillApex were evaluated. In addition, the surfaces morphologies of the sealers were analyzed by using scanning electron microscopy. For pH test, the samples were immersed in distilled water at different periods of time. The same solution was used for electrical conductivity measurement. The solubility and radiopacity were evaluated according to ANSI/ADA. Statistical analyses were carried out at 5% level of significance. MTA FillApex presented higher mean value for solubility and electrical conductivity. No significant difference was observed in the mean values for pH reading. AH Plus presented higher radiopacity mean values. MTA FillApex presented an external surface with porosities and a wide range of sizes. In conclusion, the materials fulfill the ANSI/ADA requirements when considering the radiopacity and solubility. AH Plus revealed a compact and homogeneous surface with more regular aspects and equal particle sizes.

  1. Identification and simulation evaluation of an AH-64 helicopter hover math model

    NASA Technical Reports Server (NTRS)

    Schroeder, J. A.; Watson, D. C.; Tischler, M. B.; Eshow, M. M.

    1991-01-01

    Frequency-domain parameter-identification techniques were used to develop a hover mathematical model of the AH-64 Apache helicopter from flight data. The unstable AH-64 bare-airframe characteristics without a stability-augmentation system were parameterized in the convectional stability-derivative form. To improve the model's vertical response, a simple transfer-function model approximating the effects of dynamic inflow was developed. Additional subcomponents of the vehicle were also modeled and simulated, such as a basic engine response for hover and the vehicle stick dynamic characteristics. The model, with and without stability augmentation, was then evaluated by AH-64 pilots in a moving-base simulation. It was the opinion of the pilots that the simulation was a satisfactory representation of the aircraft for the tasks of interest. The principal negative comment was that height control was more difficult in the simulation than in the aircraft.

  2. Orbital Period Investigations of Two W UMa-type Binaries: AH Aur and V728 Her

    NASA Astrophysics Data System (ADS)

    Yu, Yun-Xia; Xiang, Fu-Yuan; Hu, Ke

    2016-04-01

    The orbital period changes of two W UMa-type binaries, AH Aur and V728 Her, are investigated based on all available times of the light minimum taken from the databases and literature. It is revealed that the orbital period of AH Aur shows a long-term decrease at a rate of {dP}/{dt}=-2.491× {10}-7 days yr-1. For V728 Her, we find that the orbital period exhibits a secular increase at a rate of {dP}/{dt}=3.793× {10}-7 days yr-1. The secular period changes suggest that AH Aur and V728 Her are undergoing rapid mass transfer between the primary star and the secondary companion.

  3. Solar Jets as Sources of Outflows, Heating and Waves

    NASA Astrophysics Data System (ADS)

    Nishizuka, N.

    2013-05-01

    Recent space solar observations of the Sun, such as Hinode and SDO, have revealed that magnetic reconnection is ubiquitous in the solar atmosphere, ranging from small scale reconnection (observed as nanoflares) to large scale one (observed as long duration flares or giant arcades). Especially recent Hinode observations has found various types of tiny chromospheric jets, such as chromospheric anemone jets, penumbral microjets and light bridge jets from sunspot umbra. It was also found that the corona is full of tiny X-ray jets. Often they are seen as helical spinning jets with Alfvenic waves in the corona. Sometimes they are seen as chromospheric jets with slow-mode magnetoacoustic waves and sometimes as unresolved jet-like events at the footpoint of recurrent outflows and waves at the edge of the active region. There is increasing evidence of magnetic reconnection in these tiny jets and its association with waves. The origin of outflows and waves is one of the issues concerning coronal heating and solar wind acceleration. To answer this question, we had a challenge to reproduce solar jets with laboratory plasma experiment and directly measured outflows and waves. As a result, we could find a propagating wave excited by magnetic reconnection, whose energy flux is 10% of the released magnetic energy. That is enough for solar wind acceleration and locally enough for coronal heating, consistent with numerical MHD simulations of solar jets. Here we would discuss recent observations with Hinode, theories and experimental results related to jets and waves by magnetic reconnection, and discuss possible implication to reconnection physics, coronal heating and solar wind acceleration.

  4. Multiple Outflows in the Giant Eruption of a Massive Star

    NASA Astrophysics Data System (ADS)

    Humphreys, Roberta M.; Martin, John C.; Gordon, Michael S.; Jones, Terry J.

    2016-08-01

    The supernova impostor PSN J09132750+7627410 in NGC 2748 reached a maximum luminosity of ≈‑14 mag. It was quickly realized that it was not a true supernova, but another example of a nonterminal giant eruption. PSN J09132750+7627410 is distinguished by multiple P Cygni absorption minima in the Balmer emission lines that correspond to outflow velocities of ‑400, ‑1100, and ‑1600 km s‑1. Multiple outflows have been observed in only a few other objects. In this paper we describe the evolution of the spectrum and the P Cygni profiles for 3 months past maximum, the post-maximum formation of a cool, dense wind, and the identification of a possible progenitor. One of the possible progenitors is an infrared source. Its pre-eruption spectral energy distribution suggests a bolometric luminosity of ‑8.3 mag and a dust temperature of 780 K. If it is the progenitor, it is above the AGB limit, unlike the intermediate-luminosity red transients. The three P Cygni profiles could be due to ejecta from the current eruption, the wind of the progenitor, or previous mass-loss events. We suggest that they were all formed as part of the same high-mass-loss event and are due to material ejected at different velocities or energies. We also suggest that multiple outflows during giant eruptions may be more common than reported. Based on observations obtained with the Large Binocular Telescope (LBT), an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University and The Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia.

  5. Bipolar Outflows from Stars and Galaxies as a Tornado Phenomenon

    NASA Astrophysics Data System (ADS)

    Browne, P. F.

    1995-11-01

    At an early stage in the lives of stars and galaxies when they are surrounded by discs, vorticity in the disc concentrates into a central vortex, thus converting a Keplerian velocity fieldu ø αr -1/2 into an irrotational velocity fieldu øαr -1, which implies inward transfer of angular momentum. Centrifugal forces due to spin-up of the inner region and gravity dominant in the outer region then squeeze gas at intermediate layers, increasing pressure gradient in the axial direction sufficiently to drive a wide-angle low-velocity bipolar outflow from the disc. A logarithmic singularity of vorticity at the axis implies strong centrifugal forces which expand plasma to radiusR where pressure gradient balances centrifugal force density of ions; the much weaker centrifugal force density of electrons cannot balance pressure gradient, so that electrons are driven inwards relative to ions until charge separation limits the relative displacement. Now the radial gradient ofu øcauses ions to rotate at a different rate to electrons, generating an azimuthal current densityj øwhich is the source of an axial magnetic fieldB zin the core of the central vortex. Centrifuging carries lines of B to the core wall, where they are wound into helical force-free configuration with Bα j. An annular channel of radiusR and thickness ΔR into which parallel helical lines ofj andB are compressed constitutes a “magnetic vortex tube” (MVT). An MVT separates an inner high-velocity highly collimated outflow from the outer low-velocity wide-angle outflow, and is responsible for jets. Magnetic pinches in the MVT may constrict the core flow at HH objects.

  6. Multiple Outflows in the Giant Eruption of a Massive Star

    NASA Astrophysics Data System (ADS)

    Humphreys, Roberta M.; Martin, John C.; Gordon, Michael S.; Jones, Terry J.

    2016-08-01

    The supernova impostor PSN J09132750+7627410 in NGC 2748 reached a maximum luminosity of ≈-14 mag. It was quickly realized that it was not a true supernova, but another example of a nonterminal giant eruption. PSN J09132750+7627410 is distinguished by multiple P Cygni absorption minima in the Balmer emission lines that correspond to outflow velocities of -400, -1100, and -1600 km s-1. Multiple outflows have been observed in only a few other objects. In this paper we describe the evolution of the spectrum and the P Cygni profiles for 3 months past maximum, the post-maximum formation of a cool, dense wind, and the identification of a possible progenitor. One of the possible progenitors is an infrared source. Its pre-eruption spectral energy distribution suggests a bolometric luminosity of -8.3 mag and a dust temperature of 780 K. If it is the progenitor, it is above the AGB limit, unlike the intermediate-luminosity red transients. The three P Cygni profiles could be due to ejecta from the current eruption, the wind of the progenitor, or previous mass-loss events. We suggest that they were all formed as part of the same high-mass-loss event and are due to material ejected at different velocities or energies. We also suggest that multiple outflows during giant eruptions may be more common than reported. Based on observations obtained with the Large Binocular Telescope (LBT), an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University and The Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia.

  7. ERUPTIVE VARIABLE STARS AND OUTFLOWS IN SERPENS NW

    SciTech Connect

    Hodapp, Klaus W.; Chini, Rolf; Watermann, Ramon; Lemke, Roland

    2012-01-01

    We study the outflow activity, photometric variability, and morphology of three very young stellar objects in the Serpens NW star-forming region: OO Serpentis, EC 37 (V370 Ser), and EC 53 (V371 Ser). High spatial resolution Keck/NIRC2 laser guide star adaptive optics images obtained in 2007 and 2009 in broadband K and in a narrowband filter centered on the 1-0 S(1) emission line of H{sub 2} allow us to identify the outflows from all three objects. We also present new, seeing-limited data on the photometric evolution of the OO Ser reflection nebula and re-analyze previously published data. We find that OO Ser declined in brightness from its outburst peak in 1995 to about 2003, but that this decline has recently stopped and actually reversed itself in some areas of the reflection nebula. The morphology and proper motions of the shock fronts MHO 2218 near EC 37 suggest that they all originate in EC 37 and that this is an outflow seen nearly along its axis. We identify an H{sub 2} jet emerging from the cometary nebula EC 53. The star illuminating EC 53 is periodically variable with a period of 543 days and has a close-by, non-variable companion at a projected distance of 92 AU. We argue that the periodic variability is the result of accretion instabilities triggered by another very close, not directly observable, binary companion and that EC 53 can be understood in the model of a multiple system developing into a hierarchical configuration.

  8. Arteriovenous graft with outflow in the proximal axillary vein.

    PubMed

    Teruya, Theodore H; Schaeffer, David; Abou-Zamzam, Ahmed M; Bianchi, Christian

    2009-01-01

    Arteriovenous access can result in complications including extremity ischemia and swelling. Use of the nondominant upper extremity is preferred because complications will result in less severe disability. The distal axillary vein in the axilla is usually considered to be the end point for arteriovenous access in the upper extremity. Vascular surgeons are familiar with exposure of the proximal axillary artery via an infraclavicular incision. The axillary vein is also easily exposed through this technique. Use of this vein for arteriovenous graft outflow can preserve the dominant arm for future use. Nine patients with arteriovenous grafts with venous outflow in the proximal arm for future use. All patients had exposure to the proximal axillary vein via an infraclavicular incision. There were six women and three men. All patients had multiple failed access in the ipsilateral extremity. One patient had a loop configuration graft, while the six others had a straight graft with arterial inflow via the brachial artery. One patient had a bovine mesenteric vein graft, while the remaining six had expanded polytetrafluoroethylene grafts. Six of the seven patients had ambulatory surgery, while one patient was admitted postoperatively with mental status changes. Patency rates were 78%, with mean follow-up of 16 months. One patient had early failure due to steal and one patient failed at 22 months. Six of seven patients are alive at current follow-up. Three patients required secondary procedures including venous angioplasty (n=2) and subclavian artery stenting (n=1). The infraclavicular axillary vein can be used as an effective outflow for arteriovenous grafts. This procedure can be done as an outpatient surgery with a low complication rate. This procedure can preserve the dominant arm for future access and provides a possible alternative to surgery on another extremity.

  9. DENSE CLUMPS AND CANDIDATES FOR MOLECULAR OUTFLOWS IN W40

    SciTech Connect

    Shimoikura, Tomomi; Dobashi, Kazuhito; Nakamura, Fumitaka; Hara, Chihomi; Kawabe, Ryohei; Tanaka, Tomohiro; Shimajiri, Yoshito

    2015-06-20

    We report the results of the {sup 12}CO (J = 3−2) and HCO{sup +} (J = 4−3) observations of the W40 H ii region with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope (HPBW ≃ 22″) to search for molecular outflows and dense clumps. We found that the velocity field in the region is highly complex, consisting of at least four distinct velocity components at V{sub LSR} ≃ 3, 5, 7, and 10 km s{sup −1}. The ∼7 km s{sup −1} component represents the systemic velocity of cold gas surrounding the entire region, and causes heavy absorption in the {sup 12}CO spectra over the velocity range 6 ≲ V{sub LSR} ≲ 9 km s{sup −1}. The ∼5 and ∼10 km s{sup −1} components exhibit high {sup 12}CO temperature (≳40 K) and are found mostly around the H ii region, suggesting that these components are likely to be tracing dense gas interacting with the expanding shell around the H ii region. Based on the {sup 12}CO data, we identified 13 regions of high velocity gas, which we interpret as candidate outflow lobes. Using the HCO{sup +} data, we also identified six clumps and estimated their physical parameters. On the basis of the ASTE data and near-infrared images from 2MASS, we present an updated three-dimensional model of this region. In order to investigate molecular outflows in W40, the SiO (J = 1−0, v = 0) emission line and some other emission lines at 40 GHz were also observed with the 45 m telescope at the Nobeyama Radio Observatory, but they were not detected at the present sensitivity.

  10. Solution structure of the isolated histone H2A-H2B heterodimer.

    PubMed

    Moriwaki, Yoshihito; Yamane, Tsutomu; Ohtomo, Hideaki; Ikeguchi, Mitsunori; Kurita, Jun-Ichi; Sato, Masahiko; Nagadoi, Aritaka; Shimojo, Hideaki; Nishimura, Yoshifumi

    2016-01-01

    During chromatin-regulated processes, the histone H2A-H2B heterodimer functions dynamically in and out of the nucleosome. Although detailed crystal structures of nucleosomes have been established, that of the isolated full-length H2A-H2B heterodimer has remained elusive. Here, we have determined the solution structure of human H2A-H2B by NMR coupled with CS-Rosetta. H2A and H2B each contain a histone fold, comprising four α-helices and two β-strands (α1-β1-α2-β2-α3-αC), together with the long disordered N- and C-terminal H2A tails and the long N-terminal H2B tail. The N-terminal αN helix, C-terminal β3 strand, and 310 helix of H2A observed in the H2A-H2B nucleosome structure are disordered in isolated H2A-H2B. In addition, the H2A α1 and H2B αC helices are not well fixed in the heterodimer, and the H2A and H2B tails are not completely random coils. Comparison of hydrogen-deuterium exchange, fast hydrogen exchange, and {(1)H}-(15)N hetero-nuclear NOE data with the CS-Rosetta structure indicates that there is some conformation in the H2A 310 helical and H2B Lys11 regions, while the repression domain of H2B (residues 27-34) exhibits an extended string-like structure. This first structure of the isolated H2A-H2B heterodimer provides insight into its dynamic functions in chromatin. PMID:27181506

  11. Solution structure of the isolated histone H2A-H2B heterodimer

    PubMed Central

    Moriwaki, Yoshihito; Yamane, Tsutomu; Ohtomo, Hideaki; Ikeguchi, Mitsunori; Kurita, Jun-ichi; Sato, Masahiko; Nagadoi, Aritaka; Shimojo, Hideaki; Nishimura, Yoshifumi

    2016-01-01

    During chromatin-regulated processes, the histone H2A-H2B heterodimer functions dynamically in and out of the nucleosome. Although detailed crystal structures of nucleosomes have been established, that of the isolated full-length H2A-H2B heterodimer has remained elusive. Here, we have determined the solution structure of human H2A-H2B by NMR coupled with CS-Rosetta. H2A and H2B each contain a histone fold, comprising four α-helices and two β-strands (α1–β1–α2–β2–α3–αC), together with the long disordered N- and C-terminal H2A tails and the long N-terminal H2B tail. The N-terminal αN helix, C-terminal β3 strand, and 310 helix of H2A observed in the H2A-H2B nucleosome structure are disordered in isolated H2A-H2B. In addition, the H2A α1 and H2B αC helices are not well fixed in the heterodimer, and the H2A and H2B tails are not completely random coils. Comparison of hydrogen-deuterium exchange, fast hydrogen exchange, and {1H}-15N hetero-nuclear NOE data with the CS-Rosetta structure indicates that there is some conformation in the H2A 310 helical and H2B Lys11 regions, while the repression domain of H2B (residues 27–34) exhibits an extended string-like structure. This first structure of the isolated H2A-H2B heterodimer provides insight into its dynamic functions in chromatin. PMID:27181506

  12. Ah-receptor controlled luciferase expression: A novel species-specific bioassay for Ah-receptor active compounds in environmental matrices

    SciTech Connect

    Murk, A.J.; Aarts, J.M.M.J.G.; Koeman, J.H.; Brouwer, A.; Denison, M.S.

    1995-12-31

    Polyhalogenated aromatic hydrocarbons (PHAHs) such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) are persistent lipophilic compounds that accumulate especially in sediments and in top predators of the aquatic foodchain. PHAHs elicit a number of common toxic responses, which are highly species-specific. The most toxic, planar, PHAHs share a common mechanism of action mediated by the aryl hydrocarbon receptor (AhR). Based on this mechanism, the toxic equivalency factor (TEF) concept has been developed, allowing hazard and risk assessment for mixtures of PHAHs. The TEF-approach assumes additive responses, but also synergistic and antagonistic interactions have been observed. In addition, the often large number of compounds in a mixture, low levels of individual congeners, possible presence of unknown AhR-active substances, and species differences in inducibility, ask for an comprehensive approach in hazard assessment. A number of recombinant cell lines, including Hepa1c1c7 mouse and H411E rat hepatoma cell lines, were developed, showing AhR-mediated firefly (Photinuspyralis) luciferase gene expression. The response by 2,3,7,8-TCDD in the CALUX (chemical activated luciferase expression) assay with these cell lines is dose-dependent, and not subjected to substrate inhibition at higher ligand concentrations. The detection limit for 2,3,7,8-TCDD is below 1 pM (0.2 fmol). The luciferase assay has been successfully applied for monitoring the amount of AhR-active compounds in small aliquots of blood plasma and in both sediment and pore-water samples, of which examples will be presented.

  13. Variable outflow in the O6ef star Lambda Cephei

    NASA Technical Reports Server (NTRS)

    Leep, E. M.; Conti, P. S.

    1979-01-01

    The paper analyzes spectroscopic data from the UV region using the Copernicus satellite on six consecutive days in September, 1975. It is found that the P Cygni lines of C III at 1175 A and of N V at 1238 and 1242 A show little or no variation in their profiles. The results indicate that the changes in the 4686-A H II and H-alpha can be interpreted as a variable outflow near the surface of the star, either due to random density inhomogeneities propagating outward, or the effects of rotation of a nonspherical star, or both. Insufficient data exist at present to distinguish between periodic and random fluctuations.

  14. Alternative venous outflow vessels in microvascular breast reconstruction.

    PubMed

    Mehrara, Babak J; Santoro, Timothy; Smith, Andrew; Arcilla, Eric A; Watson, James P; Shaw, William W; Da Lio, Andrew L

    2003-08-01

    The lack of adequate recipient vessels often complicates microvascular breast reconstruction in patients who have previously undergone mastectomy and irradiation. In addition, significant size mismatch, particularly in the outflow veins, is an important contributor to vessel thrombosis and flap failure. The purpose of this study was to review the authors' experience with alternative venous outflow vessels for microvascular breast reconstruction. In a retrospective analysis of 1278 microvascular breast reconstructions performed over a 10-year period, the authors identified all patients in whom the external jugular or cephalic veins were used as the outflow vessels. Patient demographics, flap choice, the reasons for the use of alternative venous drainage vessels, and the incidence of microsurgical complications were analyzed. The external jugular was used in 23 flaps performed in procedures with 22 patients. The superior gluteal and transverse rectus abdominis musculocutaneous (TRAM) flaps were used in the majority of the cases in which the external jugular vein was used (72 percent gluteal, 20 percent TRAM flap). The need for alternative venous outflow vessels was usually due to a significant vessel size mismatch between the superior gluteal and internal mammary veins (74 percent). For three of the external jugular vein flaps (13 percent), the vein was used for salvage after the primary draining vein thrombosed, and two of three flaps in these cases were eventually salvaged. In three patients, the external jugular vein thrombosed, resulting in two flap losses, while the third was salvaged using the cephalic vein. A total of two flaps were lost in the external jugular vein group. The cephalic vein was used in 11 flaps (TRAM, 64.3 percent; superior gluteal, 35.7 percent) performed in 11 patients. In five patients (54.5 percent), the cephalic vein was used to salvage a flap after the primary draining vein thrombosed; the procedure was successful in four cases. In three

  15. Variable Accretion and Outflow in Young Brown Dwarfs

    NASA Astrophysics Data System (ADS)

    Scholz, Alexander; Jayawardhana, Ray

    2006-02-01

    We report on the first dedicated monitoring campaign of spectroscopic variability in young brown dwarfs. High-resolution optical spectra of six targets in nearby star-forming regions were obtained over 11 nights between 2005 January and March on the Magellan 6.5 m telescope. We find significant variability in Hα and a number of other emission lines related to accretion and outflow processes on a variety of timescales ranging from hours to weeks to years. The most dramatic changes are seen for 2MASS J1207334-393254 (2M 1207), 2MASS J11013205-7718249 (2M 1101), and Cha I-ISO 217. We observe possible accretion rate changes by about an order of magnitude in two of these objects, over timescales of weeks (2M 1207) or hours (2M 1101). The accretion ``burst'' seen in 2M 1101 could be due to a ``clumpy'' flow. We also see indications for changes in the outflow rate in at least three objects. In one case (ISO 217), there appears to be a ~1 hr time lag between outflow and accretion variations, consistent with a scenario in which the wind forms at the inner disk edge. For some objects there is evidence for emission-line variability induced by rotation. Our variability study supports an inclination that is close to edge-on for the brown dwarf LS-RCrA 1. The fact that all targets in our sample show variations in accretion and/or outflow indicators suggests that studies of young brown dwarf properties should be based either on large samples or on time series. As an example, we demonstrate that the large scatter in the recently found accretion rate versus mass relationship can be explained primarily by variability. The observed profile variations imply asymmetric accretion flows in brown dwarfs, which, in turn, is evidence for magnetic funneling by large-scale fields. We show that accreting substellar objects may harbor magnetic fields with approximately kilogauss strength.

  16. Right ventricular outflow tract tachycardia worsened during pregnancy.

    PubMed

    Kambiré, Yibar; Konaté, Lassina; Millogo, Georges Rosario Christian; Sib, Elodie; Amoussou, Myriam; Nebié, Lucie Valérie Adélaïde; Niakara, Ali

    2015-01-01

    We report the case of a 35 years old woman without underlying heart disease who was diagnosed with a right ventricular outflow tract tachycardia worsened during pregnancy. The diagnosis of ventricular tachycardia was made early in her pregnancy course but the patient had symptoms three months earlier. Her disease course was marked by rhythmic storms during the second trimester of pregnancy that led to three hospitalizations accounting for about two weeks in total. The combination of nadolol 80 mg and flecainide tablets 150 mg improved her rhythmic storms. Radiofrequency allowed a radical cure of this ventricular tachycardia. The patient is now asymptomatic 27 months after radiofrequency treatment. PMID:26090018

  17. Shocked molecular hydrogen in the bipolar outflow NGC 2071

    NASA Technical Reports Server (NTRS)

    Burton, Michael G.; Geballe, T. R.; Brand, P. W. J. L.

    1989-01-01

    Maps of the emission from the v = 1-0 S(1) line of molecular hydrogen in the bipolar outflow of NGC 2071 are presented. The line emission is shown to peak at six positions distributed irregularly along two lobes which are parallel to, but offset about 20 arcsec from, the lobes of the high-velocity CO-line emission. The energetics and composition of the high-velocity gas support a model in which the driving agent is a bipolar atomic wind which arises from the vicinity of the central IR sources and shocks the surrounding molecular cloud, evacuating a cavity within it.

  18. Atmospheric pollutant outflow from southern Asia: a review

    NASA Astrophysics Data System (ADS)

    Lawrence, M. G.; Lelieveld, J.

    2010-11-01

    Southern Asia, extending from Pakistan and Afghanistan to Indonesia and Papua New Guinea, is one of the most heavily populated regions of the world. Biofuel and biomass burning play a disproportionately large role in the emissions of most key pollutant gases and aerosols there, in contrast to much of the rest of the Northern Hemisphere, where fossil fuel burning and industrial processes tend to dominate. This results in polluted air masses which are enriched in carbon-containing aerosols, carbon monoxide, and hydrocarbons. The outflow and long-distance transport of these polluted air masses is characterized by three distinct seasonal circulation patterns: the winter monsoon, the summer monsoon, and the monsoon transition periods. During winter, the near-surface flow is mostly northeasterly, and the regional pollution forms a thick haze layer in the lower troposphere which spreads out over millions of square km between southern Asia and the Intertropical Convergence Zone (ITCZ), located several degrees south of the equator over the Indian Ocean during this period. During summer, the heavy monsoon rains effectively remove soluble gases and aerosols. Less soluble species, on the other hand, are lifted to the upper troposphere in deep convective clouds, and are then transported away from the region by strong upper tropospheric winds, particularly towards northern Africa and the Mediterranean in the tropical easterly jet. Part of the pollution can reach the tropical tropopause layer, the gateway to the stratosphere. During the monsoon transition periods, the flow across the Indian Ocean is primarily zonal, and strong pollution plumes originating from both southeastern Asia and from Africa spread across the central Indian Ocean. This paper provides a review of the current state of knowledge based on the many observational and modeling studies over the last decades that have examined the southern Asian atmospheric pollutant outflow and its large scale effects. An outlook

  19. Antarctic ice streams and outflow channels on Mars

    USGS Publications Warehouse

    Lucchitta, B.K.

    2001-01-01

    New sonar images of the Antarctic sea floor reveal mega-scale glacial lineations that are strikingly similar to longitudinal flutes in martian outflow channels. The analogs suggest that ice moved through the martian channels in places and carved the flutes. The ice in martian channels may have moved like Antarctic ice streams on deformable debris saturated with water under high pore pressure. On Mars, water at the base of ice-filled channels may have come from residual water or melt water liberated during past warmer climates or higher heat flows.

  20. ALMA OBSERVATIONS OF THE MASSIVE MOLECULAR OUTFLOW G331.512-0.103

    SciTech Connect

    Merello, Manuel; Bronfman, Leonardo; Garay, Guido; Lo, Nadia; Evans, Neal J. II; Nyman, Lars-Ake; Cortes, Juan R.; Cunningham, Maria R.

    2013-09-01

    The object of this study is one of the most energetic and luminous molecular outflows known in the Galaxy, G331.512-0.103. Observations with ALMA Band 7 (350 GHz; 0.86 mm) reveal a very compact, extremely young bipolar outflow and a more symmetric outflowing shocked shell surrounding a very small region of ionized gas. The velocities of the bipolar outflow are about 70 km s{sup -1} on either side of the systemic velocity. The expansion velocity of the shocked shell is {approx}24 km s{sup -1}, implying a crossing time of about 2000 yr. Along the symmetry axis of the outflow, there is a velocity feature, which could be a molecular ''bullet'' of high-velocity dense material. The source is one of the youngest examples of massive molecular outflow found associated with a high-mass star.

  1. Aryl hydrocarbon receptor knock-out exacerbates choroidal neovascularization via multiple pathogenic pathways.

    PubMed

    Choudhary, Mayur; Kazmin, Dmitri; Hu, Peng; Thomas, Russell S; McDonnell, Donald P; Malek, Goldis

    2015-01-01

    The aryl hydrocarbon receptor (AhR) is a heterodimeric transcriptional regulator with pleiotropic functions in xenobiotic metabolism and detoxification, vascular development and cancer. Herein, we report a previously undescribed role for the AhR signalling pathway in the pathogenesis of the wet, neovascular subtype of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly in the Western world. Comparative analysis of gene expression profiles of aged AhR(-/-) and wild-type (wt) mice, using high-throughput RNA sequencing, revealed differential modulation of genes belonging to several AMD-related pathogenic pathways, including inflammation, angiogenesis and extracellular matrix regulation. To investigate AhR regulation of these pathways in wet AMD, we experimentally induced choroidal neovascular lesions in AhR(-/-) mice and found that they measured significantly larger in area and volume compared to age-matched wt mice. Furthermore, these lesions displayed a higher number of ionized calcium-binding adaptor molecule 1-positive (Iba1(+) ) microglial cells and a greater amount of collagen type IV deposition, events also seen in human wet AMD pathology specimens. Consistent with our in vivo observations, AhR knock-down was sufficient to increase choroidal endothelial cell migration and tube formation in vitro. Moreover, AhR knock-down caused an increase in collagen type IV production and secretion in both retinal pigment epithelial (RPE) and choroidal endothelial cell cultures, increased expression of angiogenic and inflammatory molecules, including vascular endothelial growth factor A (VEGFA) and chemokine (C-C motif) ligand 2 (CCL2) in RPE cells, and increased expression of secreted phosphoprotein 1 (SPP1) and transforming growth factor-β1 (TGFβ1) in choroidal endothelial cells. Collectively, our findings identify AhR as a regulator of multiple pathogenic pathways in experimentally induced choroidal neovascularization, findings that

  2. Aryl hydrocarbon receptor knock-out exacerbates choroidal neovascularization via multiple pathogenic pathways

    PubMed Central

    Choudhary, Mayur; Kazmin, Dmitri; Hu, Peng; Thomas, Russell S; McDonnell, Donald P; Malek, Goldis

    2015-01-01

    The aryl hydrocarbon receptor (AhR) is a heterodimeric transcriptional regulator with pleiotropic functions in xenobiotic metabolism and detoxification, vascular development and cancer. Herein, we report a previously undescribed role for the AhR signalling pathway in the pathogenesis of the wet, neovascular subtype of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly in the Western world. Comparative analysis of gene expression profiles of aged AhR−/− and wild-type (wt) mice, using high-throughput RNA sequencing, revealed differential modulation of genes belonging to several AMD-related pathogenic pathways, including inflammation, angiogenesis and extracellular matrix regulation. To investigate AhR regulation of these pathways in wet AMD, we experimentally induced choroidal neovascular lesions in AhR−/− mice and found that they measured significantly larger in area and volume compared to age-matched wt mice. Furthermore, these lesions displayed a higher number of ionized calcium-binding adaptor molecule 1-positive (Iba1+) microglial cells and a greater amount of collagen type IV deposition, events also seen in human wet AMD pathology specimens. Consistent with our in vivo observations, AhR knock-down was sufficient to increase choroidal endothelial cell migration and tube formation in vitro. Moreover, AhR knock-down caused an increase in collagen type IV production and secretion in both retinal pigment epithelial (RPE) and choroidal endothelial cell cultures, increased expression of angiogenic and inflammatory molecules, including vascular endothelial growth factor A (VEGFA) and chemokine (C–C motif) ligand 2 (CCL2) in RPE cells, and increased expression of secreted phosphoprotein 1 (SPP1) and transforming growth factor-β1 (TGFβ1) in choroidal endothelial cells. Collectively, our findings identify AhR as a regulator of multiple pathogenic pathways in experimentally induced choroidal neovascularization, findings that

  3. Functional and phenotypic effects of AhR activation in inflammatory dendritic cells

    SciTech Connect

    Bankoti, Jaishree; Rase, Ben; Simones, Tom; Shepherd, David M.

    2010-07-15

    Aryl hydrocarbon receptor (AhR) activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces immune suppression. Dendritic cells (DCs) are key antigen presenting cells governing T cell activation and differentiation. However, the consequences of AhR activation in DCs are not fully defined. We hypothesized that AhR activation alters DC differentiation and generates dysfunctional DCs. To test this hypothesis, inflammatory bone marrow-derived DCs (BMDCs) from C57Bl/6 mice were generated in the presence of vehicle or TCDD. TCDD decreased CD11c expression but increased MHC class II, CD86 and CD25 expression on the BMDCs. The effects of TCDD were strictly AhR-dependent but not exclusively DRE-mediated. Similar effects were observed with two natural AhR ligands, 6-formylindolo[3,2-b]carbazole (FICZ) and 2-(1H-Indol-3-ylcarbonyl)-4-thiazolecarboxylic acid (ITE). TCDD increased LPS- and CpG-induced IL-6 and TNF-{alpha} production by BMDCs but decreased their NO production. TCDD decreased CpG-induced IL-12p70 production by BMDCs but did not affect their secretion of IL-10. TCDD downregulated LPS- and CpG-induced NF-kB p65 levels and induced a trend towards upregulation of RelB levels in the BMDCs. AhR activation by TCDD modulated BMDC uptake of both soluble and particulate antigens. Induction of indoleamine-2,3-dioxygenase (IDO) and TGF-{beta}3 has been implicated in the generation of regulatory T cells following AhR activation. TCDD increased IDO1, IDO2 and TGF-{beta}3 mRNA levels in BMDCs as compared to vehicle. Despite the induction of regulatory mediators, TCDD-treated BMDCs failed to suppress antigen-specific T cell activation. Thus, AhR activation can directly alter the differentiation and innate functions of inflammatory DCs without affecting their ability to successfully interact with T cells.

  4. Influenza A/H1N1 Severe Pneumonia: Novel Morphocytological Findings in Bronchoalveolar Lavage

    PubMed Central

    Faverio, Paola; Messinesi, Grazia; Brenna, Ambrogio; Pesci, Alberto

    2014-01-01

    We present the results of bronchoalveolar lavage (BAL) performed in three patients with severe influenza A/H1N1 pneumonia complicated by acute respiratory distress syndrome (ARDS). Light microscopy analysis of BAL cytocentrifugates showed the presence of characteristic large, mononuclear, plasmoblastic/plasmocytoid-like cells never described before. Via transmission electron microscopy, these cells were classified as atypical type II pneumocytes and some of them showed cytoplasmic vesicles and inclusions. We concluded that plasmoblastic/plasmocytoid-like type II pneumocytes might represent a morphologic marker of A/H1N1 influenza virus infection as well as reparative cellular activation after diffuse alveolar damage. PMID:25383078

  5. Physical Parameters of the Overcontact Binary AH Cnc in the Old Open Cluster M 67

    NASA Astrophysics Data System (ADS)

    Yakut, K.; Aerts, C.

    2006-04-01

    We present a photometric study of the overcontact binary AH Cnc. The CCD observations were done with the Russian-Turkish 1.5 m telescope and the light-curve was solved with the Wilson-Devinney code. The physical parameters of the components have been deduced as M1 = 1.22 Msun, M2 = 0.20 Msun, R1 = 1.37 Rsun, R2 = 0.66 Rsun, L1 = 2.65 Lsun and L2 = 0.63 Lsun from the obtained orbital parameters and the distance modules of M 67. AH Cnc has been compared with similar systems in the Hertzsprung-Russell diagram.

  6. Tolerogenic Phenotype of IFN-γ-Induced IDO+ Dendritic Cells Is Maintained via an Autocrine IDO-Kynurenine/AhR-IDO Loop.

    PubMed

    Li, Qingsheng; Harden, Jamie L; Anderson, Charles D; Egilmez, Nejat K

    2016-08-01

    Previous studies demonstrated that IL-12-driven antitumor activity is short-circuited by a rapid switch in dendritic cell (DC) function from immunogenic to tolerogenic activity. This process was dependent on IFN-γ and the tolerogenic phenotype was conferred by IDO. Extended monitoring of IDO(+) DC in the tumor-draining lymph nodes of IL-12 plus GM-CSF-treated tumor-bearing mice revealed that whereas IFN-γ induction was transient, IDO expression in DC was maintained long-term. An in vitro system modeling the IFN-γ-mediated change in DC function was developed to dissect the molecular basis of persistent IDO expression in post-IL-12 DC. Stimulation of DC with IFN-γ and CD40L resulted in rapid induction of IDO1 and IDO2 transcription and recapitulated the in vivo switch from immunogenic to tolerogenic activity. Long-term maintenance of IDO expression was found to be independent of exogenous and autocrine IFN-γ, or the secondary cytokines TGF-β, TNF-α, and IL-6. In contrast, both IDO enzymatic activity and IFN-γ-induced AhR expression were required for continued IDO transcription in vitro and in vivo. Addition of the tryptophan catabolite kynurenine to DC cultures in which IDO activity was blocked restored long-term IDO expression in wild-type DC but not in AhR-deficient DC, establishing the central role of the kynurenine-AhR pathway in maintaining IDO expression in tolerogenic DC. These findings shed further light on the cellular and molecular biology of the post-IL-12 regulatory rebound and provide insight into how feedback inhibitory mechanisms dominate in the long-term.

  7. Enhancement of hypoxia-induced gene expression in fish liver by the aryl hydrocarbon receptor (AhR) ligand, benzo[a]pyrene (BaP).

    PubMed

    Yu, Richard Man Kit; Ng, Patrick Kwok Shing; Tan, Tianfeng; Chu, Daniel Ling Ho; Wu, Rudolf Shiu Sun; Kong, Richard Yuen Chong

    2008-11-21

    Fish in polluted coastal habitats commonly suffer simultaneous exposure to both hypoxia and xenobiotics. Although the adaptive molecular responses to each stress have been described, little is known about the interaction between the signaling pathways mediating these responses. Previous studies in mammalian hepatoma cell lines have shown that hypoxia-inducible factor (HIF)- and/or aryl hydrocarbon receptor (AhR)-activated gene expression is suppressed following co-exposure to hypoxia and the hallmark AhR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, whether similar crosstalk exists in the non-tumor liver tissues of fish and whether other non-TCDD ligands also play the same inhibitory role in this crosstalk remain unknown. Here, the in vivo hepatic mRNA expression profiles of multiple hypoxia- and AhR-responsive genes (later gene expression=mRNA expression of the gene) were examined in the orange-spotted grouper (Epinephelus coioides) upon single and combined exposures to hypoxia and benzo[a]pyrene (BaP). Combined exposure enhanced hypoxia-induced gene expression but did not significantly alter BaP-induced gene expression. Protein carbonyl content was markedly elevated in fish subjected to combined exposure, indicating accumulation of reactive oxygen species (ROS). Application of diethyldithiocarbamate (DDC) to hypoxia-treated grouper liver explants similarly exaggerated hypoxia-induced gene expression as in the combined stress tissues in vivo. These observations suggest that ROS derived from the combined hypoxia and BaP stress have a role in enhancing hypoxia-induced gene expression.

  8. Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons

    SciTech Connect

    Voss, Paul B.; Zaveri, Rahul A.; Flocke, Frank M.; Mao, Huitimg; Hartley, Tom; DeAmicis, Pam; Deonandan, Indira; Contrerars-Jimenez, G.; Martinez-Antonio, O.; Figueroa Estrada, M.; Greenberg, David; Campos, Teresa; Weinheimer, Andrew J.; Knapp, David; Montzka, DeeDee; Crounse, J. D.; Wennberg, P. O.; Apel, Eric; Madronich, Sasha; de Foy, B.

    2010-08-04

    One of the major objectives of the Megacities Initiative: Local And Global Research 3 Observations (MILAGRO 2006) campaign was to investigate the long-range transport of 4 Mexico City Metropolitan Area (MCMA) pollution outflow and its downwind impacts on air 5 quality and climate. Four aircraft (DOE G-1, NSF/NCAR C-130, NASA-J31, and NASA 6 DC-8) made extensive chemical, aerosol, and radiation measurements above MCMA and over 7 1000 km downwind in order to characterize the evolution of MCMA pollution as it aged and 8 dispersed over the central Mexican plateau and the Gulf of Mexico. As part of this effort, 9 free-floating Controlled-Meteorological (CMET) balloons, capable of changing altitude on 10 command via satellite, characterized the MCMA outflow by performing repeated soundings 11 during the transit. In this paper, we present an analysis based on the data from two CMET 12 balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated 13 downwind with the outflow for nearly 30 hours. Continuous profile measurements made by 14 the balloons show the evolving structure of the MCMA outflow in considerable detail: its 15 stability and stratification, interaction with other air masses, mixing episodes, and dispersion 16 into the regional background. Air parcel trajectories, computed directly from the balloon 17 wind profiles, show three different transport pathways for Mexico City outflow on 18-19 18 March: (a) high-altitude advection of the top of the MCMA mixed layer, (b) low-altitude flow 19 over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf, 20 and (c) the same decoupling scenario with entrainment into a cleaner westerly jet below the 21 plateau. The C-130 intercepted the balloon-based trajectories three times on 19 March, once 22 along each transport pathway. In all three cases, distinct peaks in the urban tracer signature 23 and LIDAR backscatter imagery provided evidence for Mexico City air

  9. The digital aqueous humor outflow meter: an alternative tool for screening of the human eye outflow facility

    PubMed Central

    Kozobolis, Vassilios P; Paschalis, Eleftherios I; Foudoulakis, Nikitas C; Koukoula, Stavrenia C; Labiris, Georgios

    2010-01-01

    Purpose: To develop, characterize, and validate a prototype digital aqueous humor outflow tonographer (DAHOM). Material and methods: The DAHOM was developed, characterized, and validated in three phases. Phase 1 involved construction of the sensor. This was broadly based on the fundamental design of a typical Schiotz tonographer with a series of improvements, including corneal indentation, which was converted to an electrical signal via a linear variable differential transducer, an analog signal which was converted to digital via ADC circuitry, and digital data acquisition and processing which was made possible by a serial port interface. Phase 2 comprised development of software for automated assessment of the outflow facility. Automated outflow facility assessment incorporated a series of fundamental improvements in comparison with traditional techniques, including software-based filtering of ripple noise and extreme variations, rigidity impact analysis, and evaluation of the impact of patient age, central corneal thickness, and ocular axial length. Phase 3 comprised characterization and validation of DAHOM, for which we developed an experimental setup using porcine cadaver eyes. DAHOM’s repeatability was evaluated by means of Cronbach’s alpha and intraclass correlation coefficient. The level of agreement with a standard Schiotz tonographer was evaluated by means of paired t-tests and Bland-Altman analysis in human eyes. Results: The experimental setup provided the necessary data for the characterization of DAHOM. A fourth order polynomial equation provided excellent fit (R square >0.999). DAHOM demonstrated high repeatability (Cronbach’s alpha ≥0.997; intraclass correlation coefficient ≥0.987) and an adequate level of agreement with a standard Schiotz tonographer. Conclusions: This study presents the development, characterization, and validation of a prototype digital tonographer. DAHOM demonstrates high repeatability and a sufficient level of

  10. Searching for Outflows from the central kpc of nearby ULIRGs with OSIRIS

    NASA Astrophysics Data System (ADS)

    Rudy, Alexander R.; Max, Claire E.; Srinath, Srikar

    2016-01-01

    We present integral field spectroscopy of the central kiloparsec of 4 nearby ultra-luminous infrared-galaxies which are known to have high velocity (v≤100 km/s) molecular outflows. These observations were performed with the OH-Suppressing Infra-red Imaging Spectrograph (OSIRIS) assisted by the Keck I and II Adaptive Optics systems, which enables spatial resolutions of a few 10s of parsecs. We present the preliminary results of a survey designed to explore the relationship between AGN luminosity fraction (αAGN) and outflow properties among lower-redshift (z≤0.15) systems that we know host high velocity outflows. Our data allow us to examine the opening angle and launching point of the outflow, excitation and temperature of outflowing components (through H2 lines and high-excitation lines such as [SiIV] and [AlIX]), and molecular outflow mass in these systems. This work provides a nearby, spatially resolved analogue to higher-redshift outflows, allowing us to study the physical processes which launch outflows on their smallest scales, and relate that to the outflows which must govern the evolution of the most massive galaxies.

  11. Multi-wavelength, Multi-scale Observations of Outflows in Star-Forming Regions

    NASA Astrophysics Data System (ADS)

    Plunkett, Adele Laurie Dennis

    During the early stages of star formation, an embedded protostar accretes mass and simultaneously expels mass and angular momentum in the form of a bipolar outflow. In the common case of clustered star formation, outflows likely impact their surrounding environment and influence subsequent star formation. Numerical simulations have shown that outflows can sustain turbulence and maintain a cluster in quasi-equilibrium; alternatively, it was proposed that outflows may trigger rather than regulate or inhibit star formation. Observations of outflows and their impact on clusters are challenging because they must probe spatial scales over several orders of magnitude --- from the size of a core (a few hundred AU, or N ~ 10-3 pc) to a cluster (a few pc) --- and previous works generally focused on one scale or the other. This thesis incorporates high-resolution, high-sensitivity interferometry observations (with millimeter/sub-millimeter wavelengths) complemented by observations obtained using single dish telescopes in order to assess molecular outflow properties and their cumulative impact in two young protostellar clusters: Serpens South and NGC 1333. Based on these case studies, I develop an evolutionary scenario for clustered star formation spanning the ages of the two clusters, about 0.1 - 1 Myr. Within this scenario, outflows in both Serpens South and NGC 1333 provide sufficient energy to sustain turbulence early in the protocluster formation process. In neither cluster do outflows provide enough energy to counter the gravitational potential energy and disrupt the entire cluster. However, most of the mass in outflows in both clusters have velocities greater than the escape velocity, and therefore the relative importance of outflow-driven turbulence compared with gravitational potential likely changes with time as ambient gas escapes. We estimate that enough gas mass will escape via outflows in Serpens South so that it will come to resemble NGC 1333 in terms of its

  12. Discovery of Relativistic Outflows in the Seyfert Galaxies Ark 564 and Mrk 590

    NASA Astrophysics Data System (ADS)

    Gupta, Anjali; mathur, Smita

    2015-08-01

    Outflows are ubiquitous in AGNs, manifested by blueshifted absorption lines in the soft X-ray and UV bands and have outflow velocities of 100-1000 km s-1. The discovery of ultra-fast outflows (0.1 c) exhibited by blueshifted absorption lines in the hard X-ray band has added an intriguing aspect to the rich field of AGN outflows. The significance of these absorption line detections is often questioned and with only a few lines observed, accurate parametrization of the photoionized plasma becomes difficult. We recently discovered relativistic outflows in the soft X-ray band in two Seyfert galaxies; these detections are robust and alleviate earlier concerns about statistical significance of the lines in the hard X-ray band. I will discuss the our recent results on the discovery of high velocity outflows in the narrow line Seyfert 1 galaxies Ark 564 and Mrk 590. These absorbers are identified through multiple absorption lines at blueshift of 0.1c-0.17c detected in the Chandra HETG-MEG spectra. These high-velocity outflows have ionization parameter and column density typical of low-velocity outflows, but much higher velocity, probing a distinct region in the velocity versus ionization/column parameter space. The presence of such relativistic outflows in Seyfert galaxies poses a challenge to theoretical models of AGN winds. I will briefly discuss existing models and future prospects.

  13. Outflow forces of low-mass embedded objects in Ophiuchus: a quantitative comparison of analysis methods

    NASA Astrophysics Data System (ADS)

    van der Marel, N.; Kristensen, L. E.; Visser, R.; Mottram, J. C.; Yıldız, U. A.; van Dishoeck, E. F.

    2013-08-01

    Context. The outflow force of molecular bipolar outflows is a key parameter in theories of young stellar feedback on their surroundings. The focus of many outflow studies is the correlation between the outflow force, bolometric luminosity, and envelope mass. However, it is difficult to combine the results of different studies in large evolutionary plots over many orders of magnitude due to the range of data quality, analysis methods, and corrections for observational effects, such as opacity and inclination. Aims: We aim to determine the outflow force for a sample of low-luminosity embedded sources. We quantify the influence of the analysis method and the assumptions entering the calculation of the outflow force. Methods: We used the James Clerk Maxwell Telescope to map 12CO J = 3-2 over 2'× 2' regions around 16 Class I sources of a well-defined sample in Ophiuchus at 15″ resolution. The outflow force was then calculated using seven different methods differing, e.g., in the use of intensity-weighted emission and correction factors for inclination. Two well studied outflows (HH 46 and NGC1 333 IRAS4A) are added to the sample and included in the comparison. Results: The results from the analysis methods differ from each other by up to a factor of 6, whereas observational properties and choices in the analysis procedure affect the outflow force by up to a factor of 4. Subtraction of cloud emission and integrating over the remaining profile increases the outflow force at most by a factor of 4 compared to line wing integration. For the sample of Class I objects, bipolar outflows are detected around 13 sources including 5 new detections, where the three nondetections are confused by nearby outflows from other sources. New outflow structures without a clear powering source are discovered at the corners of some of the maps. Conclusions: When combining outflow forces from different studies, a scatter by up to a factor of 5 can be expected. Although the true outflow force

  14. Disc outflows and high-luminosity true type 2 AGN

    NASA Astrophysics Data System (ADS)

    Elitzur, Moshe; Netzer, Hagai

    2016-06-01

    The absence of intrinsic broad-line emission has been reported in a number of active galactic nuclei (AGN), including some with high Eddington ratios. Such `true type 2 AGN' are inherent to the disc-wind scenario for the broad-line region: broad-line emission requires a minimal column density, implying a minimal outflow rate and thus a minimal accretion rate. Here we perform a detailed analysis of the consequences of mass conservation in the process of accretion through a central disc. The resulting constraints on luminosity are consistent with all the cases where claimed detections of true type 2 AGN pass stringent criteria, and predict that intrinsic broad-line emission can disappear at luminosities as high as ˜4 × 1046 erg s-1 and any Eddington ratio, though more detections can be expected at Eddington ratios below ˜1 per cent. Our results are applicable to every disc outflow model, whatever its details and whether clumpy or smooth, irrespective of the wind structure and its underlying dynamics. While other factors, such as changes in spectral energy distribution or covering factor, can affect the intensities of broad emission lines, within this scenario they can only produce true type 2 AGN of higher luminosity then those prescribed by mass conservation.

  15. Giant magnetized outflows from the centre of the Milky Way.

    PubMed

    Carretti, Ettore; Crocker, Roland M; Staveley-Smith, Lister; Haverkorn, Marijke; Purcell, Cormac; Gaensler, B M; Bernardi, Gianni; Kesteven, Michael J; Poppi, Sergio

    2013-01-01

    The nucleus of the Milky Way is known to harbour regions of intense star formation activity as well as a supermassive black hole. Recent observations have revealed regions of γ-ray emission reaching far above and below the Galactic Centre (relative to the Galactic plane), the so-called 'Fermi bubbles'. It is uncertain whether these were generated by nuclear star formation or by quasar-like outbursts of the central black hole and no information on the structures' magnetic field has been reported. Here we report observations of two giant, linearly polarized radio lobes, containing three ridge-like substructures, emanating from the Galactic Centre. The lobes each extend about 60 degrees in the Galactic bulge, closely corresponding to the Fermi bubbles, and are permeated by strong magnetic fields of up to 15 microgauss. We conclude that the radio lobes originate in a biconical, star-formation-driven (rather than black-hole-driven) outflow from the Galaxy's central 200 parsecs that transports a huge amount of magnetic energy, about 10(55) ergs, into the Galactic halo. The ridges wind around this outflow and, we suggest, constitute a 'phonographic' record of nuclear star formation activity over at least ten million years.

  16. Glider observations of the Dotson Ice Shelf outflow

    NASA Astrophysics Data System (ADS)

    Miles, Travis; Lee, Sang Hoon; Wåhlin, Anna; Ha, Ho Kyung; Kim, Tae Wan; Assmann, Karen M.; Schofield, Oscar

    2016-01-01

    The Amundsen Sea is one of the most productive polynyas in the Antarctic per unit area and is undergoing rapid changes including a reduction in sea ice duration, thinning ice sheets, retreat of glaciers and the potential collapse of the Thwaites Glacier in Pine Island Bay. A growing body of research has indicated that these changes are altering the water mass properties and associated biogeochemistry within the polynya. Unfortunately difficulties in accessing the remote location have greatly limited the amount of in situ data that has been collected. In this study data from a Teledyne-Webb Slocum glider was used to supplement ship-based sampling along the Dotson Ice Shelf (DIS). This autonomous underwater vehicle revealed a detailed view of a meltwater laden outflow from below the western flank of the DIS. Circumpolar Deep Water intruding onto the shelf drives glacial melt and the supply of macronutrients that, along with ample light, supports the large phytoplankton blooms in the Amundsen Sea Polynya. Less well understood is the source of micronutrients, such as iron, necessary to support this bloom to the central polynya where chlorophyll concentrations are highest. This outflow region showed decreasing optical backscatter with proximity to the bed indicating that particulate matter was sourced from the overlying glacier rather than resuspended sediment. This result suggests that particulate iron, and potentially phytoplankton primary productivity, is intrinsically linked to the magnitude and duration of sub-glacial melt from Circumpolar Deep Water intrusions onto the shelf.

  17. Impedance-based outflow boundary conditions for human carotid haemodynamics.

    PubMed

    Malvè, M; Chandra, S; García, A; Mena, A; Martínez, M A; Finol, E A; Doblaré, M

    2014-01-01

    In this study, we develop structured tree outflow boundary conditions for modelling the human carotid haemodynamics. The model geometry was reconstructed through computerised tomography scan. Unsteady-state computational fluid dynamic analyses were performed under different conditions using a commercial software package ADINA R&D, Inc., (Watertown, MA, USA) in order to assess the impact of the boundary conditions on the flow variables. In particular, the results showed that the peripheral vessels massively impact the pressure while the flow is relatively unaffected. As an example of application of these outflow conditions, an unsteady fluid-structure interaction (FSI) simulation was carried out and the dependence of the wall shear stress (WSS) on the arterial wall compliance in the carotid bifurcation was studied. In particular, a comparison between FSI and rigid-wall models was conducted. Results showed that the WSS distributions were substantially affected by the diameter variation of the arterial wall. In particular, even similar WSS distributions were found for both cases, and differences in the computed WSS values were also found.

  18. Neutral wind effects on ion outflow at Mars

    NASA Astrophysics Data System (ADS)

    Andersson, L.; Ergun, R. E.

    2012-02-01

    This paper evaluates the influence of neutral winds on ions using the CAPIT (Combined Atmospheric Photochemistry and Ion Tracking) code, which includes ionospheric photochemistry and plasma wave energization. Based on two different wind profiles, ion outflow is, to first order, not sensitive to neutral winds. However, the ion density profiles are clearly affected by neutral winds at the exobase. For example, the direction of a strong neutral wind will dramatically change the location of the highest ion densities. This finding suggests that strongly varying neutral winds at the exobase complicate the analysis of in-situ observations. To evaluate dynamic effects of the different magnetic field configurations, crustal fields are included in the simulation domain. The outflow of O2 + ions is the most dynamic, partly because the photochemical production is almost a factor of two larger than the photochemical loss so loss to space is important (for other ions, this ratio is closer to one and loss to space is small compared to photochemical production). Since the photochemical production rate of O2 + is relatively slow, it takes time to replenish O2 + that is lost to space, so loss to space over long periods should be relatively constant.

  19. Galaxies and Galaxy Nuclei: From Hot Cores to Cold Outflows

    NASA Astrophysics Data System (ADS)

    Aalto, S.

    2015-12-01

    Studying the molecular phase of the interstellar medium in galaxies is fundamental for the understanding of the onset and evolution of star formation and the growth of supermassive black holes. We can use molecules as observational tools exploiting them as tracers of chemical, physical and dynamical conditions. In this short review, key molecules (e.g. HCN, HCO+, HNC, HC3N, CN) in identifying the nature of buried activity and its evolution are discussed including some standard astrochemical scenarios. Furthermore, we can use IR excited molecular emission to probe the very inner regions of luminous infrared galaxies (LIRGs) allowing us to get past the optically thick dust barrier of the compact obscured nuclei. We show that the vibrationally excited lines are important probes of nuclei where lines of CO, HCN and HCO+ in their vibrational ground state (ν=0) may be self-absorbed. Finally, molecular outflows are briefly discussed - including the new ALMA discovery of a highly collimated (jet-like) reversed molecular outflow in the lenticular, extremely radio-quiet galaxy NGC1377.

  20. Screen Channel Liquid Acquisition Device Outflow Tests in Liquid Hydrogen

    NASA Technical Reports Server (NTRS)

    Hartwig, Jason W.; Chato, David J.; McQuillen, J. B.; Vera, J.; Kudlac, M. T.; Quinn, F. D.

    2013-01-01

    This paper presents experimental design and test results of the recently concluded 1-g inverted vertical outflow testing of two 325x2300 full scale liquid acquisition device (LAD) channels in liquid hydrogen (LH2). One of the channels had a perforated plate and internal cooling from a thermodynamic vent system (TVS) to enhance performance. The LADs were mounted in a tank to simulate 1-g outflow over a wide range of LH2 temperatures (20.3 - 24.2 K), pressures (100 - 350 kPa), and flow rates (0.010 - 0.055 kg/s). Results indicate that the breakdown point is dominated by liquid temperature, with a second order dependence on mass flow rate through the LAD. The best performance is always achieved in the coldest liquid states for both channels, consistent with bubble point theory. Higher flow rates cause the standard channel to break down relatively earlier than the TVS cooled channel. Both the internal TVS heat exchanger and subcooling the liquid in the propellant tank are shown to significantly improve LAD performance.

  1. Discovery of a fast, broad, transient outflow in NGC 985

    NASA Astrophysics Data System (ADS)

    Ebrero, J.; Kriss, G. A.; Kaastra, J. S.; Ely, J. C.

    2016-02-01

    Aims: We observed the Seyfert 1 galaxy NGC 985 on several occasions to search for variability in its UV and X-ray absorption features to establish their location and physical properties. Methods: We used XMM-Newton to obtain X-ray spectra using the EPIC-pn camera, and the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) to obtain UV spectra. Our observations were simultaneous and span timescales of days to years. Results: We find that the soft X-ray obscuration that absorbed the low energy continuum of NGC 985 in August 2013 diminished greatly by January 2015. The total X-ray column density decreased from 2.1 × 1022 cm-2 to ~6 × 1021 cm-2. We also detect broad, fast UV absorption lines in COS spectra obtained during the 2013 obscuration event. Lines of C iii*, Lyα, Si iv, and C iv with outflow velocities of -5970 km s-1 and a full-width at half-maximum of 1420 km s-1 are prominent in the 2013 spectrum, but have disappeared in all but Lyα in the 2015 spectra. The ionization state and the column density of the UV absorbing gas is compatible with arising in the same gas as that causing the X-ray obscuration. The high velocity of the UV-absorbing gas suggests that the X-ray obscurer and the associated UV outflow are manifestations of an accretion disk wind.

  2. Ultrafast Outflows: Galaxy-scale Active Galactic Nucleus Feedback

    NASA Astrophysics Data System (ADS)

    Wagner, A. Y.; Umemura, M.; Bicknell, G. V.

    2013-01-01

    We show, using global three-dimensional grid-based hydrodynamical simulations, that ultrafast outflows (UFOs) from active galactic nuclei (AGNs) result in considerable feedback of energy and momentum into the interstellar medium (ISM) of the host galaxy. The AGN wind interacts strongly with the inhomogeneous, two-phase ISM consisting of dense clouds embedded in a tenuous, hot, hydrostatic medium. The outflow floods through the intercloud channels, sweeps up the hot ISM, and ablates and disperses the dense clouds. The momentum of the UFO is primarily transferred to the dense clouds via the ram pressure in the channel flow, and the wind-blown bubble evolves in the energy-driven regime. Any dependence on UFO opening angle disappears after the first interaction with obstructing clouds. On kpc scales, therefore, feedback by UFOs operates similarly to feedback by relativistic AGN jets. Negative feedback is significantly stronger if clouds are distributed spherically rather than in a disk. In the latter case, the turbulent backflow of the wind drives mass inflow toward the central black hole. Considering the common occurrence of UFOs in AGNs, they are likely to be important in the cosmological feedback cycles of galaxy formation.

  3. ULTRAFAST OUTFLOWS: GALAXY-SCALE ACTIVE GALACTIC NUCLEUS FEEDBACK

    SciTech Connect

    Wagner, A. Y.; Umemura, M.; Bicknell, G. V.

    2013-01-20

    We show, using global three-dimensional grid-based hydrodynamical simulations, that ultrafast outflows (UFOs) from active galactic nuclei (AGNs) result in considerable feedback of energy and momentum into the interstellar medium (ISM) of the host galaxy. The AGN wind interacts strongly with the inhomogeneous, two-phase ISM consisting of dense clouds embedded in a tenuous, hot, hydrostatic medium. The outflow floods through the intercloud channels, sweeps up the hot ISM, and ablates and disperses the dense clouds. The momentum of the UFO is primarily transferred to the dense clouds via the ram pressure in the channel flow, and the wind-blown bubble evolves in the energy-driven regime. Any dependence on UFO opening angle disappears after the first interaction with obstructing clouds. On kpc scales, therefore, feedback by UFOs operates similarly to feedback by relativistic AGN jets. Negative feedback is significantly stronger if clouds are distributed spherically rather than in a disk. In the latter case, the turbulent backflow of the wind drives mass inflow toward the central black hole. Considering the common occurrence of UFOs in AGNs, they are likely to be important in the cosmological feedback cycles of galaxy formation.

  4. Giant magnetized outflows from the centre of the Milky Way.

    PubMed

    Carretti, Ettore; Crocker, Roland M; Staveley-Smith, Lister; Haverkorn, Marijke; Purcell, Cormac; Gaensler, B M; Bernardi, Gianni; Kesteven, Michael J; Poppi, Sergio

    2013-01-01

    The nucleus of the Milky Way is known to harbour regions of intense star formation activity as well as a supermassive black hole. Recent observations have revealed regions of γ-ray emission reaching far above and below the Galactic Centre (relative to the Galactic plane), the so-called 'Fermi bubbles'. It is uncertain whether these were generated by nuclear star formation or by quasar-like outbursts of the central black hole and no information on the structures' magnetic field has been reported. Here we report observations of two giant, linearly polarized radio lobes, containing three ridge-like substructures, emanating from the Galactic Centre. The lobes each extend about 60 degrees in the Galactic bulge, closely corresponding to the Fermi bubbles, and are permeated by strong magnetic fields of up to 15 microgauss. We conclude that the radio lobes originate in a biconical, star-formation-driven (rather than black-hole-driven) outflow from the Galaxy's central 200 parsecs that transports a huge amount of magnetic energy, about 10(55) ergs, into the Galactic halo. The ridges wind around this outflow and, we suggest, constitute a 'phonographic' record of nuclear star formation activity over at least ten million years. PMID:23282363

  5. Gene cloning and expression analysis of AhR and CYP4 from Pinctada martensii after exposed to pyrene.

    PubMed

    Du, Junqiao; Liao, Chenghong; Zhou, Hailong; Diao, Xiaoping; Li, Yuhu; Zheng, Pengfei; Wang, Fuqiang

    2015-10-01

    Pyrene, a typical polycyclic aromatic hydrocarbon, is a common pollutant in the marine environment. Polycyclic aromatic hydrocarbons initiate cellular detoxification in an exposed organism via the activation of the aryl hydrocarbon receptor (AhR). Subsequent metabolism of these xenobiotics is mainly by the cytochrome P450 enzymes of the phase I detoxification system. Full-length complementary DNA sequences from the pearl oyster Pinctada martensii (pm) encoding AhR and cytochrome P4 were cloned. The P. martensii AhR complementary DNA sequence constitutes an open reading frame that encodes for 848 amino acids. Sequence analysis indicated PmAhR showed high similarity with its homologues of other bivalve species. The cytochrome P(CYP)4 complementary DNA sequence of P. martensii constitutes an open reading frame that encodes for 489 amino acids. Quantitative real-time analysis detected both PmAhR and PmCYP4 messenger RNA expressions in the mantle, gill, hepatapancreas and adductor muscle of P. martensii exposed to pyrene. The highest transcript-band intensities of PmAhR and PmCYP4 were observed in the gill. Temporal expression of PmAhR and PmCYP4 messenger RNAs induction was observed in gills and increased between 3 and 5 days post exposure; then returned to control level. These results suggest that messenger RNAs of PmAhR and PmCYP4 in pearl oysters might be useful parameters for monitoring marine environment pyrene pollution.

  6. ATel 7477: Classification of PS15ahs as a Type Ia Supernova

    NASA Astrophysics Data System (ADS)

    Piascik, A. S.; Steele, I. A.

    2015-05-01

    We conducted a spectroscopic observation of transient PS15ahs (Atel #7471) at 2015-05-06T00:57:23 UT. One spectrum was obtained in the visible (400-800nm) with resolution R~350 using the SPRAT spectrograph on the Liverpool Telescope located at Roque de los Muchachos. ...

  7. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11)

    PubMed Central

    Forn-Cuní, Gabriel; Tomás, Juan M.

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced. PMID:27587829

  8. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34)

    PubMed Central

    Forn-Cuní, Gabriel; Tomás, Juan M.

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern. PMID:27587828

  9. AH-64 monocular HMD visual assessment during urban combat in operation Iraqi freedom (OIF)

    NASA Astrophysics Data System (ADS)

    Rash, Clarence E.; Heinecke, J. Kevin; Hiatt, Keith L.

    2007-04-01

    In the first two decades of the fielding of the monocular helmet-mounted display (HMD) flown in the U.S. Army's AH-64 Apache attack helicopter, a number of studies reported a significant incidence of physical visual symptoms and illusions. In 2004, a similar study looked at the presence of these complaints during the first combat phase of Operation Iraqi Freedom (OIF). The study found a general trend of a reduced frequency of complaints associated with the AH-64's HMD. A follow-up study has been conducted to validate this downward trend and to investigate the impact the shift in mission role of the AH-64 from one of open-field tank hunter to one of close-quarter urban combat. Thirty-eight AH-64D pilots were asked to complete a survey questionnaire that solicited data about the presence and frequency of the visual complaints reported in previous studies. Data for physical visual symptoms and static and dynamic illusions were found not to be significantly different from frequencies reported in the previous OIF study. Both OIF studies reported headache as the prominent physical complaint with height judgment and slope estimation as the most frequently reported static illusions and with undetected drift and faulty closure judgment as the two most frequently reported dynamic illusions.

  10. Stress analysis of 27% scale model of AH-64 main rotor hub

    NASA Technical Reports Server (NTRS)

    Hodges, R. V.

    1985-01-01

    Stress analysis of an AH-64 27% scale model rotor hub was performed. Component loads and stresses were calculated based upon blade root loads and motions. The static and fatigue analysis indicates positive margins of safety in all components checked. Using the format developed here, the hub can be stress checked for future application.

  11. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-09-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced.

  12. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-09-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern.

  13. A Challenge for Social Studies Educators: Teaching about Islam, "Jihad," and "Shari'ah" Law

    ERIC Educational Resources Information Center

    Moore, James R.

    2012-01-01

    In this article, the author investigates the controversial curricular and instructional aspects of teaching about Islam in social studies courses. Specifically, the author discusses pedagogically sound approaches to teaching about "jihad" and "Shari'ah" law, two of the most important and controversial concepts in Islam that often generate intense…

  14. Influenza A(H10N7) Virus in Dead Harbor Seals, Denmark

    PubMed Central

    Hansen, Mette S.; Holm, Elisabeth; Hjulsager, Charlotte K.; Chriél, Mariann; Pedersen, Karl; Andresen, Lars O.; Abildstrøm, Morten; Jensen, Trine H.; Larsen, Lars E.

    2015-01-01

    Since April 2014, an outbreak of influenza in harbor seals has been ongoing in northern Europe. In Denmark during June–August, 152 harbor seals on the island of Anholt were found dead from severe pneumonia. We detected influenza A(H10N7) virus in 2 of 4 seals examined. PMID:25811098

  15. Influenza A(H1N1)pdm09 virus infection in giant pandas, China.

    PubMed

    Li, Desheng; Zhu, Ling; Cui, Hengmin; Ling, Shanshan; Fan, Shengtao; Yu, Zhijun; Zhou, Yuancheng; Wang, Tiecheng; Qian, Jun; Xia, Xianzhu; Xu, Zhiwen; Gao, Yuwei; Wang, Chengdong

    2014-03-01

    We confirmed infection with influenza A(H1N1)pdm09 in giant pandas in China during 2009 by using virus isolation and serologic analysis methods. This finding extends the host range of influenza viruses and indicates a need for increased surveillance for and control of influenza viruses among giant pandas. PMID:24565026

  16. Potentially-toxic and essential elements profile of AH1N1 patients in Mexico City

    PubMed Central

    Moya, Mireya; Bautista, Edgar G.; Velázquez-González, Antonio; Vázquez-Gutiérrez, Felipe; Tzintzun, Guadalupe; García-Arreola, María Elena; Castillejos, Manuel; Hernández, Andrés

    2013-01-01

    During spring of 2009, a new influenza virus AH1N1 spread in the world causing acute respiratory illness and death, resulting in the first influenza pandemic since 1968. Blood levels of potentially-toxic and essential elements of 40 pneumonia and confirmed AH1N1 were evaluated against two different groups of controls, both not infected with the pandemic strain. Significant concentrations of potentially-toxic elements (lead, mercury, cadmium, chromium, arsenic) along with deficiency of selenium or increased Zn/Cu ratios characterized AH1N1 cases under study when evaluated versus controlled cases. Deficiency of selenium is progressively observed from controls I (influenza like illness) through controls II (pneumonia) and finally pneumonia -AH1N1 infected patients. Cases with blood Se levels greater than the recommended for an optimal cut-off to activate glutathione peroxidase (12.5 μg/dL) recovered from illness and survived. Evaluation of this essential element in critical pneumonia patients at the National Institutes is under evaluation as a clinical trial. PMID:23422930

  17. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern. PMID:27587828

  18. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced. PMID:27587829

  19. An in vitro rainbow trout cell bioassay for AhR-mediated toxins

    SciTech Connect

    Richter, C.A.; Giesy, J.P.; Denison, M.S.

    1995-12-31

    The toxicity of PCBs, dioxins, and other halogenated aromatic hydrocarbons (HAHS) at environmentally relevant concentrations is in large part mediated through the aromatic hydrocarbon receptor (AhR). Bioassays which measure the activity of genes regulated by the receptor provide an integrative measure of the total AhR-mediated toxicity of a sample. The authors have recently developed and characterized a bioassay using recombinant rainbow trout hepatoma cells containing the firefly luciferase reporter gene under the regulation of the AhR. The cell line is designated Remodulated Lightning Trout (RLT). The RLT bioassay is relevant to fish, and is useful as a rapid screening device, a guide for chemical analysis, and a tool for studies of the AhR mechanism. The responses of the RLT cell line to various PCB congeners are similar to responses of in vivo fish bioassays. The authors now report on the responses of the bioassay to dioxins, dibenzofurans, and other related compounds as compared to in vivo fish bioassays. The authors will also report on the utility of the RLT bioassay in measuring the total TEQ of complex mixtures.

  20. Development of a 10 Ah, Prismatic, Lithium-Ion Cell for NASA/GSFC

    NASA Technical Reports Server (NTRS)

    Stein, Brian; Baker, John W.; George, Douglas S.; Isaacs, Nathan D.; Shah, Pinakin M.; Rao, Gopalakrishna M.; Day, John H. (Technical Monitor)

    2001-01-01

    MSA's 10 Ah Li-ion cell is a rugged design suitable for the stringent requirements of aerospace applications. Eighteen cells demonstrate consistent cycling performance over a wide range of rates and temperatures. The cell passes qualification requirements for vibration survivability technology improvements at MSA continue to enhance cell performance.

  1. Research Updates: Experimental Evaluation of 2009 Pandemic A/H1N1 in Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: In March 2009, a novel pandemic A/H1N1 emerged in the human population in North America (2). The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before be...

  2. Human influenza A(H7N9) virus infection associated with poultry farm, Northeastern China.

    PubMed

    Fan, Ming; Huang, Biao; Wang, Ao; Deng, Liquan; Wu, Donglin; Lu, Xinrong; Zhao, Qinglong; Xu, Shuang; Havers, Fiona; Wang, Yanhui; Wu, Jing; Yin, Yuan; Sun, Bingxin; Yao, Jianyi; Xiang, Nijuan

    2014-11-01

    We report on a case of human infection with influenza A(H7N9) virus in Jilin Province in northeastern China. This case was associated with a poultry farm rather than a live bird market, which may point to a new focus for public health surveillance and interventions in this evolving outbreak.

  3. Novel reassortant influenza A(H5N8) viruses in domestic ducks, eastern China.

    PubMed

    Wu, Haibo; Peng, Xiaorong; Xu, Lihua; Jin, Changzhong; Cheng, Linfang; Lu, Xiangyun; Xie, Tiansheng; Yao, Hangping; Wu, Nanping

    2014-08-01

    Domestic ducks are natural reservoirs of avian influenza viruses and serve as reassortant hosts for new virus subtypes. We isolated 2 novel influenza A(H5N8) viruses from domestic ducks in eastern China, sequenced their genomes, and tested their pathogenicity in chickens and mice. Circulation of these viruses may pose health risks for humans.

  4. Influenza A(H1N1)pdm09 virus infection in giant pandas, China.

    PubMed

    Li, Desheng; Zhu, Ling; Cui, Hengmin; Ling, Shanshan; Fan, Shengtao; Yu, Zhijun; Zhou, Yuancheng; Wang, Tiecheng; Qian, Jun; Xia, Xianzhu; Xu, Zhiwen; Gao, Yuwei; Wang, Chengdong

    2014-03-01

    We confirmed infection with influenza A(H1N1)pdm09 in giant pandas in China during 2009 by using virus isolation and serologic analysis methods. This finding extends the host range of influenza viruses and indicates a need for increased surveillance for and control of influenza viruses among giant pandas.

  5. Martian groundwater outflow processes and morphology; reconstruction of paleohydrology using landscape evolution experiments

    NASA Astrophysics Data System (ADS)

    Marra, Wouter A.; Kleinhans, Maarten G.; de Jong, Steven M.; Hauber, Ernst

    2015-04-01

    Groundwater played an important role in the aqueous history of Mars but how, how long, and with what intensity remains unclear. Two types of fluvial landforms related to groundwater emergence are the giant outflow channels and the disputed sapping valleys. Understanding of the relation between subsurface and surface processes is slim, which limits inferences of climate implications from the observable morphology. We aim to increase this understanding and to apply this knowledge to Martian cases to reconstruct former hydrological conditions. Using a series of sandbox experiments, we investigated formative processes of valleys formed by groundwater. These experiments showed the morphology and processes of groundwater sapping and pressurized groundwater outflow (see Marra et al, 2014, Icarus doi:10.1016/j.icarus.2013.12.026) and further focused on landscape characteristics of groundwater sapping sourced locally or distally, and identified various processes linked to pressurized groundwater outbursts including the formation and eruption of subsurface reservoirs that can explain the high reconstructed discharges of large outflow valleys (see Marra et al, 2014, JGR doi:10.1002/2014JE004701). Based on the experiments, we identified novel morphological indicators for groundwater outflow in the outflow channel region of Lunae and Ophir Plana. These, in combination with the classic outflow features, show a clear trend of increasing outflow magnitude with decreasing elevation to the northeast, indicating a head from a common aquifer. The putative aquifer we identified was likely recharged by infiltration over the Tharsis region. Outflow channel activity peaked in the Hesperian, but continued in the Amazonian at a lower magnitude. Our results agree well with groundwater recharge in the Noachian and Early Hesperian, corresponding to a climate that sustained an active hydrological cycle. Furthermore, the large outflow events require a confining layer to build up enough pressure

  6. A statistical study of plasmaspheric plumes and ionospheric outflows observed at the dayside magnetopause

    NASA Astrophysics Data System (ADS)

    Lee, S. H.; Zhang, H.; Zong, Q.-G.; Otto, A.; Rème, H.; Liebert, E.

    2016-01-01

    We present a statistical study of plasmaspheric plumes and ionospheric outflows observed by the Cluster spacecraft near the dayside magnetopause. Plasmaspheric plumes are identified when the low-energy ions (<1 keV) with ˜90° pitch angle distributions are observed by the Cluster Ion Spectrometer/Hot Ion Analyzer instrument. The ionospheric outflows are characterized by unidirectional or bidirectional field-aligned pitch angle distributions of low-energy ions observed in the dayside magnetosphere. Forty-three (10%) plasmaspheric plume events and 32 (7%) ionospheric outflow events were detected out of the 442 times that C3 crossed the dayside magnetopause between 2007 and 2009. The occurrence rate of plumes at duskside is significantly higher than that at dawnside. The occurrence rate of outflows shows a weak dawn-dusk asymmetry. We investigate the dependence of the occurrence rates of plumes and ionospheric outflows on geomagnetic activity and on solar wind/interplanetary magnetic field (IMF) conditions. The plume events tend to occur during southward IMF (duskward solar wind electric field) and moderate geomagnetic activity (Kp = 3,-30≤Dst <- 10 nT). However, the ionospheric outflow events tend to occur during northward IMF (dawnward solar wind electric field). The ionospheric outflows do not occur when Kp = 0, and the occurrence rate of the ionospheric outflows does not have a clear Dst dependence. Seventy-five percent (46%) of the outflows are observed in the duskside for negative (positive) IMF By. Conversely, 54% (25%) of the outflows are observed in the dawnside for positive (negative) IMF By. Finally, the occurrence rates of both plumes and outflows increase with solar wind dynamic pressure.

  7. French Experience of 2009 A/H1N1v Influenza in Pregnant Women

    PubMed Central

    Dubar, Grégory; Azria, Elie; Tesnière, Antoine; Dupont, Hervé; Le Ray, Camille; Baugnon, Thomas; Matheron, Sophie; Luton, Dominique; Richard, Jean-Christophe; Launay, Odile; Tsatsaris, Vassilis; Goffinet, François; Mignon, Alexandre

    2010-01-01

    Background The first reports on the pandemic influenza 2009 A/H1N1v from the USA, Mexico, and Australia indicated that this disease was associated with a high mortality in pregnant women. The aim of this study was to describe and compare the characteristics of severe critically ill and non-severe pregnant women with 2009 A/H1N1v-related illness in France. Methodology/Principal Findings A national registry was created to screen pregnant women with laboratory-confirmed 2009 A/H1N1v influenza. Three hundred and fifteen patients from 46 French hospitals were included: 40 patients were admitted to intensive care units (severe outcomes), 111 were hospitalized in obstetric or medical wards (moderate outcomes), and 164 were outpatients (mild outcomes). The 2009 A/H1N1v influenza illness occurred during all pregnancy trimesters, but most women (54%), notably the severe patients (70%), were in the third trimester. Among the severe patients, twenty (50%) underwent mechanical ventilation, and eleven (28%) were treated with extracorporeal membrane oxygenation. Three women died from A/H1N1v influenza. We found a strong association between the development of a severe outcome and both co-existing illnesses (adjusted odds ratio [OR], 5.1; 95% confidence interval [CI], 2.2–11.8) and a delay in oseltamivir treatment after the onset of symptoms (>3 or 5 days) (adjusted OR, 4.8; 95% CI, 1.9–12.1 and 61.2, 95% CI; 14.4–261.3, respectively). Among the 140 deliveries after 22 weeks of gestation known to date, 19 neonates (14%) were admitted to a neonatal intensive care unit, mainly for preterm delivery, and two neonates died. None of these neonates developed 2009 A/H1N1v infection. Conclusions This series confirms the high incidence of complications in pregnant women infected with pandemic A/H1N1v observed in other countries but depicts a lower overall maternal and neonatal mortality and morbidity than indicated in the USA or Australia. Moreover, our data demonstrate the benefit of

  8. AH Cam: A metal-rich RR Lyrae star with the shortest known Blazhko period

    NASA Technical Reports Server (NTRS)

    Smith, Horace A.; Matthews, Jaymie M.; Lee, Kevin M.; Williams, Jeffrey; Silbermann, N. A.; Bolte, Michael

    1994-01-01

    Analysis of 746 new V-band observations of the RR Lyrae star AH Cam obtained during 1989 - 1992 clearly show that its light curve cannot be described by a single period. In fact, at first glance, the Fourier spectrum of the photometry resembles that of a double-mode pulsator, with peaks at a fundamental period of 0.3686 d and an apparent secondary period of 0.2628 d. Nevertheless, the dual-mode solution is a poor fit to the data. Rather, we believe that AH Cam is a single-mode RR Lyrae star undergoing the Blazhko effect: periodic modulation of the amplitude and shape of its light curve. What was originally taken to be the period of the second mode is instead the 1-cycle/d alias of a modulation sidelobe in the Fourier spectrum. The data are well described by a modulation period of just under 11 d, which is the shortest Blazhko period reported to date in the literature and confirms the earlier suggestion by Goranskii. A low-resolution spectrum of AH Cam indicates that it is relatively metal rich, with delta-S less than or = 2. Its high metallicity and short modulation period may provide a critical test of at least one theory for the Blazhko effect. Moskalik's internal resonance model makes specific predictions of the growth rate of the fundamental model vs fundamental period. AH Cam falls outside the regime of other known Blazhko variables and resonance model predictions, but these are appropriate for metal-poor RR Lyrae stars. If the theory matches the behavior of AH Cam for a metal-rich stellar model, this would bolster the resonance hypothesis.

  9. Atrazine affects kidney and adrenal hormones (AHs) related genes expressions of rare minnow (Gobiocypris rarus).

    PubMed

    Yang, Lihua; Zha, Jinmiao; Li, Wei; Li, Zhaoli; Wang, Zijian

    2010-05-01

    Atrazine, one of the most widely used herbicides, has been proved to interfere with sexual hormones. However few studies have considered the effects of atrazine on adrenal hormones (AH). In this study, rare minnow (Gobiocypris rarus) was exposed to 0, 3, 10, 33, 100 and 333microg/l atrazine for 28 days. The histopathology of kidney and gill was examined and the expressions of AHs-related genes including Na(+),K(+)-ATPase, glucocorticoid receptor (gr), heat shock protein 70 (hsp70), and heat shock protein 90 (hsp90) in kidney and gill were quantitatively determined. Histopathological observation revealed obvious lesions in gill including hyperplasia, necrosis in epithelium region, aneurysm and lamellar fusion at concentrations as low as 10microg/l. The observed lesions in kidney included extensive expansion in the lumen, degenerative and necrotic changes of the tubular epithelia, shrinkage of the glomerulus as well as increase of the Bowman's space at concentrations as low as 10microg/l. The expressions of Na(+),K(+)-ATPase, gr, hsp70 and hsp90 in the kidney of females were significantly decreased at all concentrations. For males, the expressions of hsp90 in the kidney of all treated groups were significantly down-regulated, while gr at all concentrations and hsp70 at 10, 33, 100microg/l were significantly up-regulated. However in the gill, the expressions of these genes were not significantly different from the control. These results indicated that exposure to atrazine caused impairments of kidney and gill of fish at environmental related concentrations. Histopathological lesions could partly attribute to the changes of the expressions of AHs-related genes in kidney. We concluded also that atrazine is a potential AHs-disruptor and AHs-related genes in kidney of fish could be used as sensitive molecular biomarkers.

  10. The launch region of the SVS 13 outflow and jet

    SciTech Connect

    Hodapp, Klaus W.; Chini, Rolf E-mail: rolf.chini@astro.ruhr-uni-bochum.de

    2014-10-20

    We present the results of Keck telescope laser adaptive-optics integral field spectroscopy with OSIRIS of the innermost regions of the NGC 1333 SVS 13 outflow that forms the system of Herbig-Haro objects 7-11. We find a bright 0.''2 long microjet traced by the emission of shock-excited [Fe II]. Beyond the extent of this jet, we find a series of bubbles and fragments of bubbles that are traced in the lower excitation H{sub 2} 1-0 S(1) line. While the most recent outflow activity is directed almost precisely (P.A. ≈ 145°) to the southeast of SVS 13, there is clear indication that prior bubble ejections were pointed in different directions. Within these variations, a clear connection between the newly observed bubble ejection events and the well-known, poorly collimated HH 7-11 system of Herbig-Haro objects is established. The astrometry of the youngest of the expanding shock fronts at three epochs, covering a timespan of over 2 yr, gives kinematic ages for two of these bubbles. The kinematic age of the youngest bubble is slightly older than the historically observed last photometric outburst of SVS 13 in 1990, consistent with that event, launching the bubble and some deceleration of its expansion. A re-evaluation of historic infrared photometry and new data show that SVS 13 has not yet returned to its brightness before that outburst and thus reveal behavior similar to FUor outbursts, albeit with a smaller amplitude. We postulate that the creation of a series of bubbles and the changes in outflow direction are indicative of a precessing disk and accretion events triggered by a repetitive phenomenon possibly linked to the orbit of a close binary companion. However, our high-resolution images in the H and K bands do not directly detect any companion object. We have tried, but failed, to detect the kinematic rotation signature of the microjet in the [Fe II] emission line at 1.644 μm.

  11. Asymptotic distribution of the maximum deficit with correlated, partially regulated outflows.

    USGS Publications Warehouse

    Troutman, B.M.

    1983-01-01

    The asymptotic distribution of the maximum accumulated deficit with partially regulated, Markov-dependent net outflows having a Bernoulli distribution is derived, and the distribution for independent, continuous outflows is presented. Under partial regulation the maximum deficit behaves as log n, where n is the length of the series.-from Author

  12. DETECTION OF HIGH VELOCITY OUTFLOWS IN THE SEYFERT 1 GALAXY Mrk 590

    SciTech Connect

    Gupta, A.; Mathur, S.; Krongold, Y.

    2015-01-01

    We report on the detection of ultra-fast outflows in the Seyfert 1 galaxy Mrk 590. These outflows are identified through highly blueshifted absorption lines of O VIII and Ne IX in the medium energy grating spectrum and Si XIV and Mg XII in the high energy grating spectrum on board the Chandra X-ray observatory. Our best-fit photoionization model requires two absorber components at outflow velocities of 0.176c and 0.0738c and a third tentative component at 0.0867c. The components at 0.0738c and 0.0867c have high ionization parameters and high column densities, similar to other ultra-fast outflows detected at low resolution by Tombesi et al. We also found suggestive evidence for super-solar silicon in these components. These outflows carry sufficient mass and energy to provide effective feedback proposed by theoretical models. The component at 0.176c, on the other hand, has a low ionization parameter and low column density, similar to those detected by Gupta et al. in Ark 564. These absorbers occupy a different locus on the velocity versus ionization parameter plane and have opened up a new parameter space of active galactic nucleus (AGN) outflows. The presence of ultra-fast outflows in moderate luminosity AGNs poses a challenge to models of AGN outflows.

  13. Modified technique for heterotopic implantation of a right ventricular outflow tract conduit.

    PubMed

    Dave, Hitendu; Dodge-Khatami, Ali; Kadner, Alexander; Prêtre, René

    2006-06-01

    This article describes a modified technique of side-to-side proximal connection of a conduit during heterotopic implantation in the right ventricular outflow tract. It results in a better geometry of the right ventricular outflow and avoids distortion of the valve annulus, especially when the newer generation of straight xenografts are used. PMID:16731190

  14. MASSIVE MOLECULAR OUTFLOWS AND NEGATIVE FEEDBACK IN ULIRGs OBSERVED BY HERSCHEL-PACS

    SciTech Connect

    Sturm, E.; Gracia-Carpio, J.; Hailey-Dunsheath, S.; Contursi, A.; Poglitsch, A.; Davies, R.; Genzel, R.; Lutz, D.; Tacconi, L.; De Jong, J. A.; Gonzalez-Alfonso, E.; Veilleux, S.; Fischer, J.; Sternberg, A.; Verma, A.; Maiolino, R.

    2011-05-20

    Mass outflows driven by stars and active galactic nuclei (AGNs) are a key element in many current models of galaxy evolution. They may produce the observed black-hole-galaxy mass relation and regulate and quench both star formation in the host galaxy and black hole accretion. However, observational evidence of such feedback processes through outflows of the bulk of the star-forming molecular gas is still scarce. Here we report the detection of massive molecular outflows, traced by the hydroxyl molecule (OH), in far-infrared spectra of ULIRGs obtained with Herschel-PACS as part of the SHINING key project. In some of these objects the (terminal) outflow velocities exceed 1000 km s{sup -1}, and their outflow rates (up to {approx}1200 M{sub sun} yr{sup -1}) are several times larger than their star formation rates. We compare the outflow signatures in different types of ULIRGs and in starburst galaxies to address the issue of the energy source (AGN or starburst) of these outflows. We report preliminary evidence that ULIRGs with a higher AGN luminosity (and higher AGN contribution to L{sub IR}) have higher terminal velocities and shorter gas depletion timescales. The outflows in the observed ULIRGs are able to expel the cold gas reservoirs from the centers of these objects within {approx}10{sup 6}-10{sup 8} years.

  15. Financial Crisis, Capital Outflows, and Policy Responses: Examples from East Asia

    ERIC Educational Resources Information Center

    Rajan, Ramkishen S.

    2007-01-01

    Financial crises seem to have become the norm rather than the exception since 1992. The author examines the impact of a crisis of confidence and resultant capital outflows from a small and open economy and the possible policy options in response to such outflows, using simple tools and definitions that will be familiar to any money and banking or…

  16. Investigations of protostellar outflow launching and gas entrainment: Hydrodynamic simulations and molecular emission

    SciTech Connect

    Offner, Stella S. R.; Arce, Héctor G.

    2014-03-20

    We investigate protostellar outflow evolution, gas entrainment, and star formation efficiency using radiation-hydrodynamic simulations of isolated, turbulent low-mass cores. We adopt an X-wind launching model, in which the outflow rate is coupled to the instantaneous protostellar accretion rate and evolution. We vary the outflow collimation angle from θ = 0.01-0.1 and find that even well-collimated outflows effectively sweep up and entrain significant core mass. The Stage 0 lifetime ranges from 0.14-0.19 Myr, which is similar to the observed Class 0 lifetime. The star formation efficiency of the cores spans 0.41-0.51. In all cases, the outflows drive strong turbulence in the surrounding material. Although the initial core turbulence is purely solenoidal by construction, the simulations converge to approximate equipartition between solenoidal and compressive motions due to a combination of outflow driving and collapse. When compared to simulation of a cluster of protostars, which is not gravitationally centrally condensed, we find that the outflows drive motions that are mainly solenoidal. The final turbulent velocity dispersion is about twice the initial value of the cores, indicating that an individual outflow is easily able to replenish turbulent motions on sub-parsec scales. We post-process the simulations to produce synthetic molecular line emission maps of {sup 12}CO, {sup 13}CO, and C{sup 18}O and evaluate how well these tracers reproduce the underlying mass and velocity structure.

  17. ISOTROPICALLY DRIVEN VERSUS OUTFLOW DRIVEN TURBULENCE: OBSERVATIONAL CONSEQUENCES FOR MOLECULAR CLOUDS

    SciTech Connect

    Carroll, Jonathan J.; Frank, Adam; Blackman, Eric G.

    2010-10-10

    Feedback from protostellar outflows can influence the nature of turbulence in star-forming regions even if they are not the primary source of velocity dispersion for all scales of molecular clouds. For the rate and power expected in star-forming regions, we previously (Carroll et al.) demonstrated that outflows could drive supersonic turbulence at levels consistent with the scaling relations from Matzner although with a steeper velocity power spectrum than expected for an isotropically driven supersonic turbulent cascade. Here, we perform higher resolution simulations and combine simulations of outflow driven turbulence with those of isotropically forced turbulence. We find that the presence of outflows within an ambient isotropically driven turbulent environment produces a knee in the velocity power spectrum at the outflow scale and a steeper slope at sub-outflow scales than for a purely isotropically forced case. We also find that the presence of outflows flattens the density spectrum at large scales effectively reducing the formation of large-scale turbulent density structures. These effects are qualitatively independent of resolution. We have also carried out Principal Component Analysis (PCA) for synthetic data from our simulations. We find that PCA as a tool for identifying the driving scale of turbulence has a misleading bias toward low amplitude large-scale velocity structures even when they are not necessarily the dominant energy containing scales. This bias is absent for isotropically forced turbulence but manifests strongly for collimated outflow driven turbulence.

  18. Flood surge through the Lunae Planum Outflow Complex, Mars

    NASA Technical Reports Server (NTRS)

    De Hon, R. A.; Pani, E. A.

    1992-01-01

    It is shown that the Maja outflow on Mars was released as a catastrophic outburst from Juventae Chasma. The flood surge traveled the first two-thirds of its length as a semiconfined sheetflood in a broad trough formed by the eastward-sloping Lunae Planum surface and the Xanthe Terra highlands to the east. At its northernmost extent, the flow ponded on the northern Lunae Planum surface. As the flow impounded on the upper Maja lake, waters rose to spill over the Xanthe Terra revetment onto the lower Chryse Planitia surface. The initial spillover crossed Xanthe Terra as sheetflood flow that muted topography over which it passed. The sheetflood was rapidly broken by the irregular topography to cut a complex series of anastomosing channels. A few main channels on eventually captured most of the drainage and local ponds formed in breached craters and irregular basins. The Maja Valles canyon eventually captured the remaining flow at the expense of all other channels.

  19. Jets and Outflows in Radio Galaxies: Implications for AGN Feedback

    NASA Astrophysics Data System (ADS)

    Torresi, Eleonora; Grandi, Paola; Costantini, Elisa; Palumbo, Giorgio G. C.

    One of the main debated astrophysical problems is the role of the AGN feedback in galaxy formation. It is known that massive black holes have a profound effect on the formation and evolution of galaxies, but how black holes and galaxies communicate is still an unsolved problem. For Radio Galaxies, feedback studies have mainly focused on jet/cavity systems in the most massive and X-ray luminous galaxy clusters. The recent high-resolution detection of warm absorbers in some Broad Line Radio Galaxies allow us to investigate the interplay between the nuclear engine and the surrounding medium from a different perspective. We report on the detection of warm absorbers in two Broad Line Radio Galaxies, 3C 382 and 3C 390.3, and discuss the physical and energetic properties of the absorbing gas. Finally, we attempt a comparison between radio-loud and radio-quiet outflows.

  20. Paleoceanography. Onset of Mediterranean outflow into the North Atlantic.

    PubMed

    Hernández-Molina, F Javier; Stow, Dorrik A V; Alvarez-Zarikian, Carlos A; Acton, Gary; Bahr, André; Balestra, Barbara; Ducassou, Emmanuelle; Flood, Roger; Flores, José-Abel; Furota, Satoshi; Grunert, Patrick; Hodell, David; Jimenez-Espejo, Francisco; Kim, Jin Kyoung; Krissek, Lawrence; Kuroda, Junichiro; Li, Baohua; Llave, Estefania; Lofi, Johanna; Lourens, Lucas; Miller, Madeline; Nanayama, Futoshi; Nishida, Naohisa; Richter, Carl; Roque, Cristina; Pereira, Hélder; Sanchez Goñi, Maria Fernanda; Sierro, Francisco J; Singh, Arun Deo; Sloss, Craig; Takashimizu, Yasuhiro; Tzanova, Alexandrina; Voelker, Antje; Williams, Trevor; Xuan, Chuang

    2014-06-13

    Sediments cored along the southwestern Iberian margin during Integrated Ocean Drilling Program Expedition 339 provide constraints on Mediterranean Outflow Water (MOW) circulation patterns from the Pliocene epoch to the present day. After the Strait of Gibraltar opened (5.33 million years ago), a limited volume of MOW entered the Atlantic. Depositional hiatuses indicate erosion by bottom currents related to higher volumes of MOW circulating into the North Atlantic, beginning in the late Pliocene. The hiatuses coincide with regional tectonic events and changes in global thermohaline circulation (THC). This suggests that MOW influenced Atlantic Meridional Overturning Circulation (AMOC), THC, and climatic shifts by contributing a component of warm, saline water to northern latitudes while in turn being influenced by plate tectonics.

  1. Venous outflow of the brain after bilateral complete jugular ligation.

    PubMed

    Ensari, Serdar; Kaptanoğlu, Erkan; Tun, Kağan; Gün, Taylan; Beşkonakli, Etem; Celikkanat, Serdar; Dere, Hüseyin; Cekirge, Saruhan

    2008-01-01

    A case of a patient with bilateral internal, external, posterior external and anterior jugular vein ligations and excisions performed in the neck due to a larynx tumor is presented. Radical neck dissection is a standard otorhinolaryngological procedure in the management of head and neck cancer patients with bilateral lymph node metastasis to the neck. Sacrifice of both internal and external jugular veins bilaterally has been recognized as a dangerous approach leading to intracranial hypertension with subsequent neurological sequela and death. In this report, we aimed to demonstrate how venous outflow from the brain diverts after jugular venous system obliteration. After bilateral jugular vein ligations, digital subtraction angiography (DSA) showed that the venous drainage route of the brain had been diverted from the jugular veins to the vertebral venous plexus. PMID:18382980

  2. Paleoceanography. Onset of Mediterranean outflow into the North Atlantic.

    PubMed

    Hernández-Molina, F Javier; Stow, Dorrik A V; Alvarez-Zarikian, Carlos A; Acton, Gary; Bahr, André; Balestra, Barbara; Ducassou, Emmanuelle; Flood, Roger; Flores, José-Abel; Furota, Satoshi; Grunert, Patrick; Hodell, David; Jimenez-Espejo, Francisco; Kim, Jin Kyoung; Krissek, Lawrence; Kuroda, Junichiro; Li, Baohua; Llave, Estefania; Lofi, Johanna; Lourens, Lucas; Miller, Madeline; Nanayama, Futoshi; Nishida, Naohisa; Richter, Carl; Roque, Cristina; Pereira, Hélder; Sanchez Goñi, Maria Fernanda; Sierro, Francisco J; Singh, Arun Deo; Sloss, Craig; Takashimizu, Yasuhiro; Tzanova, Alexandrina; Voelker, Antje; Williams, Trevor; Xuan, Chuang

    2014-06-13

    Sediments cored along the southwestern Iberian margin during Integrated Ocean Drilling Program Expedition 339 provide constraints on Mediterranean Outflow Water (MOW) circulation patterns from the Pliocene epoch to the present day. After the Strait of Gibraltar opened (5.33 million years ago), a limited volume of MOW entered the Atlantic. Depositional hiatuses indicate erosion by bottom currents related to higher volumes of MOW circulating into the North Atlantic, beginning in the late Pliocene. The hiatuses coincide with regional tectonic events and changes in global thermohaline circulation (THC). This suggests that MOW influenced Atlantic Meridional Overturning Circulation (AMOC), THC, and climatic shifts by contributing a component of warm, saline water to northern latitudes while in turn being influenced by plate tectonics. PMID:24926012

  3. Outflows, Jets and Shocks in the Orion Nebula

    NASA Technical Reports Server (NTRS)

    ODell, C. R.; Bally, John

    2000-01-01

    The rich young cluster of stars associated with the Orion Nebula provides a unique laboratory for the study of plasma phenomena. We see five types of flows and shocks. Photoablation outflow from the proplyds nearest theta (exp 1) Ori C form nearly stationary shocks with the high velocity wind from that star. Microjets, with scales of less than 10 (exp 4) AU, are seen around some 20 low mass stars. Isolated jets, with high velocities and scales of about, 104 AU, are less numerous but common. One also sees the shocks formed when these jets impinge on the ionized nebular gas and the neutral gas in the foreground lid. The final type of object is the stationary shock formed by the interaction from the stellar wind that arises during disk formation with the ambient, gas flowing away from the main body of the nebula.

  4. Chasma Australe Mars: Structural Framework for a Catastrophic Outflow Origin

    NASA Technical Reports Server (NTRS)

    Anguita, F.; Babin, R.; Benito, G.; Collado, A.; Gomez, D.; Rice, J. W.

    1998-01-01

    Chasma Australe is the most remarkable of the martian south pole erosional reentrants carved in the polar layered deposits. Ms chasma originates near the south pole and runs across the polar troughs over a distance of about 500 km. Its width varies between 20 and 80 km and, with a depth up to 1000 m, it reaches the bedrock. Following an idea put forward originally for Chasma Boreale, we propose for the genesis of Chasma Australe a mechanism of catastrophic outflow preceded by a tectonically induced powerful sapping process. A detailed geomorphological analysis of Chasma Australe shows erosional and depositional features that can be interpreted as produced by the motion of a fluid. Like other polar reentrants, Chasma Australe is clearly assymetric, with a steep eastern margin where basal and lateral erosion prevailed, and a gentler western side, where the stepped topography and bedrock spurs favored deposition.

  5. Doubling of Ion Up-flow for Ion Outflow Calculations

    NASA Astrophysics Data System (ADS)

    Carlson, H. C.; Moen, J. I.; Oksavik, K.; Aruliah, A. L.; Skjaeveland, A.

    2013-12-01

    Estimates of O+ ion escape fluxes from the ionosphere to the magnetosphere, involve the combination of ionospheric O+ up-flow to adequate altitudes for intermediate altitude acceleration processes to boost them into storage in the magnetosphere. Calculations of ambiploar up-flow based on measured ion and electron gas temperatures lead to ion up-flows order 100 m/s in the vicinity of 400 km, but are found to be only order half ion up-flow velocities observed. It has been speculated that this calculated shortfall can be explained by magnetic reconnection, leading to plasma flow jets, in turn leading to frictional drag heating of the thermosphere and consequent upwelling of the neutral rest frame within which ambipolar up-flow occurs. We report here the first direct observations confirming this mechanism for order doubling the ion up-flow speeds. This new perspective needs to be added to thinking within the heavy ion outflow community.

  6. Irrelevance of information outflow in opinion dynamics models

    NASA Astrophysics Data System (ADS)

    Castellano, Claudio; Pastor-Satorras, Romualdo

    2011-01-01

    The Sznajd model for opinion dynamics has attracted a large interest as a simple realization of the psychological principle of social validation. As its most salient feature, it has been claimed that the Sznajd model is qualitatively different from other ordering processes because it is the only one featuring outflow of information as opposed to inflow. We show that this claim is unfounded by presenting a generalized zero-temperature Glauber type of dynamics, which yields results indistinguishable from those of the Sznajd model. In one dimension, we also derive an exact expression for the exit probability of the Sznajd model, which turns out to coincide with the result of an analytical approach based on the Kirkwood approximation. This observation raises interesting questions about the applicability and limitations of this approach.

  7. Rotational structure and outflow in the infrared dark cloud 18223-3

    NASA Astrophysics Data System (ADS)

    Fallscheer, C.; Beuther, H.; Zhang, Q.; Keto, E.; Sridharan, T. K.

    2009-09-01

    Aims: We examine an Infrared Dark Cloud (IRDC) at high spatial resolution as a means to study rotation, outflow, and infall at the onset of massive star formation. Methods: The IRDC 18223-3 was observed at 1.1 mm and 1.3 mm with the Submillimeter Array (SMA) and follow-up short spacing information was obtained with the IRAM 30 m telescope. Additional data were taken at 3 mm with the IRAM Plateau de Bure interferometer (PdBI). Results: Submillimeter Array observations combined with IRAM 30 m data in 12CO(2-1) reveal the outflow orientation in the IRDC 18223-3 region, and PdBI 3 mm observations confirm this orientation in other molecular species. The implication of the outflow's presence is that an accretion disk is feeding it, so using line data for high density tracers such as C18O, N2H^+, and CH3OH, we looked for indications of a velocity gradient perpendicular to the outflow direction. Surprisingly, this gradient turns out to be most apparent in CH3OH. The large size (28 000 AU) of the flattened rotating object detected indicates that this velocity gradient cannot be due solely to a disk, but rather from inward spiraling gas within which a Keplerian disk likely exists. The rotational signatures can be modeled via rotationally infalling gas. From the outflow parameters, we derive properties of the source such as an outflow dynamical age of ~37 000 years, outflow mass of ~13 M⊙, and outflow energy of ˜1.7 × 1046 erg. While the outflow mass and energy are clearly consistent with a high-mass star forming region, the outflow dynamical age indicates a slightly more evolved evolutionary stage than previous spectral energy distribution (SED) modeling indicates. Conclusions: The orientation of the molecular outflow associated with IRDC 18223-3 is in the northwest-southeast direction and velocity gradients orthogonal to the outflow reveal a large rotating structure likely harboring an accretion disk within. We also present a model of the observed methanol velocity

  8. The Mixing State of Black Carbon in Asian Outflow (Invited)

    NASA Astrophysics Data System (ADS)

    Kondo, Y.; Moteki, N.; Takegawa, N.; Oshima, N.; Sahu, L. K.

    2009-12-01

    Black carbon (BC) aerosol efficiently absorbs visible sunlight and heats the atmosphere. The magnitude of the photo-absorption of BC depends on its particle size distribution and mixing state (coating thickness or shell/core diameter ratio). In addition, the efficiency of wet removal of BC is sensitive to mixing state. Therefore, it is critically important to understand the evolution of the mixing state of BC, especially in Asia, where BC emissions are largest. The size distribution and mixing state of BC were measured by an SP2 instrument over the East China Sea and Yellow Sea in March-April 2009 during the A-FORCE (Aerosol-Radiative Forcing in East Asia) aircraft campaign. Aircraft sampling was made in air masses strongly influenced by emissions from China, Korea, and Japan in the latitude region between 27 and 37N. In the boundary layer, the mass median diameter of BC was stable at about 200 nm in air masses with ages exceeding 1 day. BC in these air masses was thickly coated even over the Yellow Sea at distances of only a few hundred km from the coastlines of China and Korea. Thinly coated (shell/core diameter ratio < 1.2) BC was observed only in the vicinity of urban areas of Korea and Japan. The dominance of thickly coated BC in the moderately aged outflow is consistent with our previous ground-based and aircraft measurements showing that BC coating proceeds within 24 hours in the outflow of urban air. The variability of the observed BC mixing state is interpreted in terms of available volatile aerosol compounds.

  9. Ultrafast outflows in radio-loud active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Tombesi, F.; Tazaki, F.; Mushotzky, R. F.; Ueda, Y.; Cappi, M.; Gofford, J.; Reeves, J. N.; Guainazzi, M.

    2014-09-01

    Recent X-ray observations show absorbing winds with velocities up to mildly relativistic values of the order of ˜0.1c in a limited sample of six broad-line radio galaxies. They are observed as blueshifted Fe XXV-XXVI K-shell absorption lines, similarly to the ultrafast outflows (UFOs) reported in Seyferts and quasars. In this work we extend the search for such Fe K absorption lines to a larger sample of 26 radio-loud active galactic nuclei (AGN) observed with XMM-Newton and Suzaku. The sample is drawn from the Swift Burst Alert Telescope 58-month catalogue and blazars are excluded. X-ray bright Fanaroff-Riley Class II radio galaxies constitute the majority of the sources. Combining the results of this analysis with those in the literature we find that UFOs are detected in >27 per cent of the sources. However, correcting for the number of spectra with insufficient signal-to-noise ratio, we can estimate that the incidence of UFOs is this sample of radio-loud AGN is likely in the range f ≃ (50 ± 20) per cent. A photoionization modelling of the absorption lines with XSTAR allows us to estimate the distribution of their main parameters. The observed outflow velocities are broadly distributed between vout ≲ 1000 km s-1 and vout ≃ 0.4c, with mean and median values of vout ≃ 0.133c and vout ≃ 0.117c, respectively. The material is highly ionized, with an average ionization parameter of logξ ≃ 4.5 erg s-1 cm, and the column densities are larger than NH > 1022 cm-2. Overall, these characteristics are consistent with the presence of complex accretion disc winds in a significant fraction of radio-loud AGN and demonstrate that the presence of relativistic jets does not preclude the existence of winds, in accordance with several theoretical models.

  10. Cooling and Freshening of the Weddell Sea Outflow

    NASA Astrophysics Data System (ADS)

    Heywood, K. J.; Thompson, A. F.; Fahrbach, E.; Mackensen, A.; Aoki, S.

    2009-04-01

    The Weddell Sea is the primary source of the coldest, densest water invading most of the world ocean, known as Antarctic Bottom Water. The formation process involves brine rejection during sea ice formation, which salinifies the relatively fresh waters on the Antarctic continental shelf. Mixing with meltwater from the floating Antarctic ice shelves is believed to contribute also. When it becomes sufficiently dense, the shelf waters can spill down the continental slope as a deep outflow plume, mixing as it descends with the warmer and saltier Warm Deep Water above. By the time the plume reaches the western Weddell Sea, it is a narrow ribbon of cold, dense water hugging the continental slope. Here we will show that this outflow is now colder and fresher than in any of the observations since 1989. This freshening is comparable in magnitude to that seen in bottom water off Adelie Land which implies that the freshening is circumpolar, contrary to some recent analyses. This is likely associated with freshening of source waters on the continental shelf of Antarctica caused by an accelerated hydrological cycle and/or additional melting of the Antarctic ice sheet. Such melting may in turn be caused by a strengthening of the circumpolar winds associated with the Southern Annular Mode, leading to a southward ocean transport of heat towards the Antarctic. The Weddell Sea freshening may have been exacerbated by the break-up of the Larsen Ice Shelf on the eastern Antarctic Peninsula in the late 1990s, leaving a large expanse of continental shelf able to host the formation of sea ice and hence form dense bottom water.

  11. UNDERSTANDING GALAXY OUTFLOWS AS THE PRODUCT OF UNSTABLE TURBULENT SUPPORT

    SciTech Connect

    Scannapieco, Evan

    2013-02-01

    The interstellar medium is a multiphase gas in which turbulent support is as important as thermal pressure. Sustaining this configuration requires both continuous turbulent stirring and continuous radiative cooling to match the decay of turbulent energy. While this equilibrium can persist for small turbulent velocities, if the one-dimensional velocity dispersion is larger than Almost-Equal-To 35 km s{sup -1}, the gas moves into an unstable regime that leads to rapid heating. I study the implications of this turbulent runaway, showing that it causes a hot gas outflow to form in all galaxies with a gas surface density above Almost-Equal-To 50 M{sub Sun} pc{sup -2}, corresponding to a star formation rate per unit area of Almost-Equal-To 0.1 M{sub Sun} yr{sup -1} kpc{sup -2}. For galaxies with v{sub esc} {approx}> 200 km s{sup -1}, the sonic point of this hot outflow should lie interior to the region containing cold gas and stars, while for galaxies with smaller escape velocities, the sonic point should lie outside this region. This leads to efficient cold cloud acceleration in higher mass galaxies, while in lower mass galaxies, clouds may be ejected by random turbulent motions rather than accelerated by the wind. Finally, I show that energy balance cannot be achieved at all for turbulent media above a surface density of Almost-Equal-To 10{sup 5} M{sub Sun} pc{sup -2}.

  12. Shocks in nova outflows - II. Synchrotron radio emission

    NASA Astrophysics Data System (ADS)

    Vlasov, Andrey; Vurm, Indrek; Metzger, Brian D.

    2016-11-01

    The discovery of GeV gamma-rays from classical novae indicates that shocks and relativistic particle acceleration are energetically key in these events. Further evidence for shocks comes from thermal keV X-ray emission and an early peak in the radio light curve on a time-scale of months with a brightness temperature which is too high to result from freely expanding photoionized gas. Paper I developed a one-dimensional model for the thermal emission from nova shocks. This work concluded that the shock-powered radio peak cannot be thermal if line cooling operates in the post-shock gas at the rate determined by collisional ionization equilibrium. Here we extend this calculation to include non-thermal synchrotron emission. Applying our model to three classical novae, we constrain the amplification of the magnetic field ɛB and the efficiency ɛe of accelerating relativistic electrons of characteristic Lorentz factor γ ˜ 100. If the shocks are radiative (low velocity vsh ≲ 1000 km s-1) and cover a large solid angle of the nova outflow, as likely characterize those producing gamma-rays, then values of ɛe ˜ 0.01-0.1 are required to achieve the peak radio brightness for ɛB = 10-2. Such high efficiencies exclude secondary pairs from pion decay as the source of the radio-emitting particles, instead favouring the direct acceleration of electrons at the shock. If the radio-emitting shocks are instead adiabatic (high velocity), as likely characterize those responsible for the thermal X-rays, then much higher brightness temperatures are possible, allowing the radio-emitting shocks to cover a smaller outflow solid angle.

  13. Regionally Discrete Aqueous Humor Outflow Quantification Using Fluorescein Canalograms

    PubMed Central

    Roy, Pritha; Schuman, Joel S.; Sigal, Ian A.; Loewen, Nils A.

    2016-01-01

    Purpose To visualize and quantify conventional outflow directly in its anatomic location. Methods We obtained fluorescein canalograms in six porcine whole eyes and six porcine anterior segment cultures. Eyes were perfused with a constant pressure of 15 mmHg using media containing 0.017 mg/ml fluorescein. Flow patterns were visualized using a stereo dissecting microscope equipped for fluorescent imaging. Images were captured every 30 seconds for 20 minutes for time lapse analysis. Anterior chamber cultures were imaged again on day three of culture. Canalograms were first analyzed for filling time per quadrant. We then wrote a program to automatically compute focal flow fits for each macropixel and to detect convergent perilimbal flow patterns with macropixels grouped into 3 equal-radial width rings around the cornea. A generalized additive model was used to determine fluorescence changes of individual macropixels. Results The resulting imaging algorithm deployed 1024 macropixels that were fit to determine maximum intensity and time to fill. These individual fits highlighted the focal flow function. In whole eyes, significantly faster flow was seen in the inferonasal (IN) and superonasal (SN) quadrants compared to the superotemporal (ST) and inferotemporal (IT) ones (p<0.05). In anterior chamber cultures, reduced flow on day 1 increased in all quadrants on day 3 except in IT (p<0.05). Perilimbal ring analysis uncovered convergent perilimbal flow. Conclusions An algorithm was developed that analyzes regional and circumferential outflow patterns. This algorithm found flow patterns that changed over time and differ in whole eyes and anterior segment cultures. PMID:26998833

  14. Shocks in nova outflows. II. Synchrotron radio emission

    NASA Astrophysics Data System (ADS)

    Vlasov, Andrey; Vurm, Indrek; Metzger, Brian D.

    2016-08-01

    The discovery of GeV gamma-rays from classical novae indicates that shocks and relativistic particle acceleration are energetically key in these events. Further evidence for shocks comes from thermal keV X-ray emission and an early peak in the radio light curve on a timescale of months with a brightness temperature which is too high to result from freely expanding photo-ionized gas. Paper I developed a one dimensional model for the thermal emission from nova shocks. This work concluded that the shock-powered radio peak cannot be thermal if line cooling operates in the post-shock gas at the rate determined by collisional ionization equilibrium. Here we extend this calculation to include non-thermal synchrotron emission. Applying our model to three classical novae, we constrain the amplification of the magnetic field ɛB and the efficiency ɛe of accelerating relativistic electrons of characteristic Lorentz factor γ ˜ 100. If the shocks are radiative (low velocity v_sh ≲ 1000 km s-1) and cover a large solid angle of the nova outflow, as likely characterize those producing gamma-rays, then values of ɛe ˜ 0.01 - 0.1 are required to achieve the peak radio brightness for ɛB = 10-2. Such high efficiencies exclude secondary pairs from pion decay as the source of the radio-emitting particles, instead favoring the direct acceleration of electrons at the shock. If the radio-emitting shocks are instead adiabatic (high velocity), as likely characterize those responsible for the thermal X-rays, then much higher brightness temperatures are possible, allowing the radio-emitting shocks to cover a smaller outflow solid angle.

  15. Radiation-MHD Simulations of Black Hole Accretion Flows and Outflows

    NASA Astrophysics Data System (ADS)

    Ohsuga, K.

    2012-08-01

    We perform two-dimensional radiation-magnetohydrodynamic simulations of the accretion disks, jets, and disk outflows around black holes. We can reproduce the three distinct inflow-outflow modes, which corresponds to the two-dimensional version of the slim disk model, the standard disk model, and the radiatively inefficient accretion flow, with one numerical code. In the case of the super-Eddington accretion flow, we find that a radiatively driven, magnetically collimated jet is produced around the rotation axis and that a time-dependent, clumpy outflow with larger opening angle forms. Such jet and outflow might resolve the relativistic powerful jets of the luminous compact objects and the ultra fast outflows of active galactic nuclei.

  16. Venous outflow reconstruction in living donor liver transplantation: Dealing with venous anomalies

    PubMed Central

    Jeng, Long-Bin; Thorat, Ashok; Yang, Horng-Ren; Li, Ping-Chun

    2015-01-01

    The reconstruction of the vascular outflow tract of partial liver grafts has received considerable attention in the past, especially in the setting of right liver grafts with undrained segments. Hepatic venous outflow reconstruction is an important factor for successful living donor liver transplantation outcome. However, in presence of undrained anterior sector and presence of multiple short hepatic veins that drain substantial portions of liver, outflow reconstruction without backtable venoplasty may lead to severe graft congestion and subsequent graft dysfunction. Various backtable venoplasty techniques in presence of multiple hepatic veins that can be used in either right- or left-lobe liver transplantation are devised to ensure a single, wide outflow channel. In this overview, various techniques to overcome the hepatic venous variations of liver allograft and outflow reconstruction are discussed. PMID:26722643

  17. Formation and spreading of Red Sea Outflow Water in the Red Sea

    NASA Astrophysics Data System (ADS)

    Zhai, Ping; Bower, Amy S.; Smethie, William M.; Pratt, Larry J.

    2015-09-01

    Hydrographic data, chlorofluorocarbon-12 (CFC-12) and sulfur hexafluoride (SF6) measurements collected in March 2010 and September-October 2011 in the Red Sea, as well as an idealized numerical experiment are used to study the formation and spreading of Red Sea Outflow Water (RSOW) in the Red Sea. Analysis of inert tracers, potential vorticity distributions, and model results confirm that RSOW is formed through mixed-layer deepening caused by sea surface buoyancy loss in winter in the northern Red Sea and reveal more details on RSOW spreading rates, pathways, and vertical structure. The southward spreading of RSOW after its formation is identified as a layer with minimum potential vorticity and maximum CFC-12 and SF6. Ventilation ages of seawater within the RSOW layer, calculated from the partial pressure of SF6 (pSF6), range from 2 years in the northern Red Sea to 15 years at 17°N. The distribution of the tracer ages is in agreement with the model circulation field which shows a rapid transport of RSOW from its formation region to the southern Red Sea where there are longer circulation pathways and hence longer residence time due to basin wide eddies. The mean residence time of RSOW within the Red Sea estimated from the pSF6 age is 4.7 years. This time scale is very close to the mean transit time (4.8 years) for particles from the RSOW formation region to reach the exit at the Strait of Bab el Mandeb in the numerical experiment.

  18. Stellar Populations, Outflows, and Morphologies of High-Redshift Galaxies

    NASA Astrophysics Data System (ADS)

    Kornei, Katherine Anne

    Understanding the regulation and environment of star formation across cosmic time is critical to tracing the build-up of mass in the Universe and the interplay between the stars and gas that are the constituents of galaxies. Three studies are presented in this thesis, each examining a different aspect of star formation at a specific epoch. The first study presents the results of a photometric and spectroscopic survey of 321 Lyman break galaxies (LBGs) at z ˜ 3 to investigate systematically the relationship between Lyalpha emission and stellar populations. Lyalpha equivalent widths were calculated from rest-frame UV spectroscopy and optical/near-infrared/Spitzer photometry was used in population synthesis modeling to derive the key properties of age, dust extinction, star formation rate (SFR), and stellar mass. Using a variety of statistical tests, we find that Lyalpha equivalent width and age, SFR, and dust extinction, respectively, are significantly correlated in the sense that objects with strong Lyalpha emission also tend to be older, lower in star formation rate, and less dusty than objects with weak Lyalpha emission, or the line in absorption. We accordingly conclude that, within the LBG sample, objects with strong Lyalpha emission represent a later stage of galaxy evolution in which supernovae-induced outflows have reduced the dust covering fraction. The second study focuses specifically on galactic-scale outflowing winds in 72 star-forming galaxies at z ˜ 1 in the Extended Groth Strip. Galaxies were selected from the DEEP2 survey and follow-up LRIS spectroscopy was obtained covering SiII, CIV, FeII, MgII, and MgI lines in the rest-frame ultraviolet. Using GALEX, HST, and Spitzer imaging available for the Extended Groth Strip, we examine galaxies on a per-object basis in order to better understand both the prevalence of galactic outflows at z ˜ 1 and the star-forming and structural properties of objects experiencing outflows. Gas velocities, measured from

  19. NUCLEOSYNTHESIS IN THE OUTFLOWS ASSOCIATED WITH ACCRETION DISKS OF TYPE II COLLAPSARS

    SciTech Connect

    Banerjee, Indrani; Mukhopadhyay, Banibrata E-mail: bm@physics.iisc.ernet.in

    2013-11-20

    We investigate nucleosynthesis inside the outflows from gamma-ray burst (GRB) accretion disks formed by the Type II collapsars. In these collapsars, massive stars undergo core collapse to form a proto-neutron star initially, and a mild supernova (SN) explosion is driven. The SN ejecta lack momentum, and subsequently this newly formed neutron star gets transformed to a stellar mass black hole via massive fallback. The hydrodynamics and the nucleosynthesis in these accretion disks have been studied extensively in the past. Several heavy elements are synthesized in the disk, and much of these heavy elements are ejected from the disk via winds and outflows. We study nucleosynthesis in the outflows launched from these disks by using an adiabatic, spherically expanding outflow model, to understand which of these elements thus synthesized in the disk survive in the outflow. While studying this, we find that many new elements like isotopes of titanium, copper, zinc, etc., are present in the outflows. {sup 56}Ni is abundantly synthesized in most of the cases in the outflow, which implies that the outflows from these disks in a majority of cases will lead to an observable SN explosion. It is mainly present when outflow is considered from the He-rich, {sup 56}Ni/{sup 54}Fe-rich zones of the disks. However, outflow from the Si-rich zone of the disk remains rich in silicon. Although emission lines of many of these heavy elements have been observed in the X-ray afterglows of several GRBs by Chandra, BeppoSAX, XMM-Newton, etc., Swift seems to have not yet detected these lines.

  20. JCMT HARP CO 3-2 observations of molecular outflows in W5

    NASA Astrophysics Data System (ADS)

    Ginsburg, Adam; Bally, John; Williams, Jonathan P.

    2011-12-01

    New James Clerk Maxwell Telescope (JCMT) HARP CO 3-2 observations of the W5 star forming complex are presented, totalling an area of ˜12 000 arcmin2 with sensitivity better than 0.1 K per 0.4 km s-1 channel. We discovered 55 CO outflow candidates, of which 40 are associated with W5 and 15 are more distant than the Perseus arm. Most of the outflows are located on the periphery of the W5 H II region. However, two outflow clusters are >5 pc from the ionization fronts, indicating that their driving protostars formed without directly being triggered by the O-stars in W5. We compare the derived outflow properties to those in Perseus and find that the total W5 outflow mass is surprisingly low given the cloud masses. The outflow mass deficiency in the more massive W5 cloud [M(H2) ˜ 5 × 104 M⊙] can be explained if ionizing radiation dissociates molecules as they break out of their host cloud cores. Although CO J = 3-2 is a good outflow tracer, it is likely to be a poor mass tracer because of sub-thermal line excitation and high opacity, which may also contribute to the outflow mass discrepancy. It is unlikely that outflows could provide the observed turbulent energy in the W5 molecular clouds even accounting for undetected outflow material. Many cometary globules have been observed with velocity gradients from head to tail, displaying strong interaction with the W5 H II region and exhibiting signs of triggered or revealed star formation in their heads. Because it is observed face-on, W5 is an excellent region to study feedback effects, both positive and negative, of massive stars on star formation.

  1. AhV_aPA-induced vasoconstriction involves the IP₃Rs-mediated Ca²⁺ releasing.

    PubMed

    Zeng, Fuxing; Zou, Zhisong; Niu, Liwen; Li, Xu; Teng, Maikun

    2013-08-01

    AhV_aPA, the acidic PLA₂ purified from Agkistrodon halys pallas venom, was previously reported to possess a strong enzymatic activity and can remarkably induce a further contractile response on the 60 mM K⁺-induced contraction with an EC₅₀ in 369 nM on mouse thoracic aorta rings. In the present study, we found that the p-bromo-phenacyl-bromide (pBPB), which can completely inhibit the enzymatic activity of AhV_aPA, did not significantly reduce the contractile response on vessel rings induced by AhV_aPA, indicating that the vasoconstrictor effects of AhV_aPA are independent of the enzymatic activity. The inhibitor experiments showed that the contractile response induced by AhV_aPA is mainly attributed to the Ca²⁺ releasing from Ca²⁺ store, especially sarcoplasmic reticulum (SR). Detailed studies showed that the Ca²⁺ release from SR is related to the activation of inositol trisphosphate receptors (IP₃Rs) rather than ryanodine receptors (RyRs). Furthermore, the vasoconstrictor effect could be strongly reduced by pre-incubation with heparin, indicating that the basic amino acid residues on the surface of AhV_aPA may be involved in the interaction between AhV_aPA and the molecular receptors. These findings offer new insights into the functions of snake PLA₂ and provide a novel pathogenesis of A. halys pallas venom.

  2. DDE and PCB 153 independently induce aryl hydrocarbon receptor (AhR) expression in peripheral blood mononuclear cells.

    PubMed

    Gaspar-Ramírez, Octavio; Pérez-Vázquez, Francisco J; Salgado-Bustamante, Mariana; González-Amaro, Roberto; Hernandez-Castro, Berenice; Pérez-Maldonado, Ivan N

    2015-01-01

    Recent studies have demonstrated that compounds inducing pro-inflammatory cytokines enhance AhR expression. The aim of this study was 2-fold: (1) to determine if two pro-inflammatory compounds, dichlorodiphenyldichloroethylene (DDE) and 2,2',4,4',5,5'-hexa-chlorobiphenyl (PCB 153), independently affect AhR gene expression in peripheral blood mononuclear cells (PBMC); and (2) if affected, to determine whether the mechanism involved was due to AhR activation or to a pro-inflammatory effect of the chemicals. PBMC isolated from healthy individuals were incubated in the presence of DDE (10 µg/ml) and PCB 153 (20 ng/ml) over time and AhR and CYP1A1 expression was assessed with a real-time PCR technique. The results indicated there was over-expression of the AhR mRNA in PBMC when the cells were treated with DDE and PCB 153. No changes in expression levels of CYP1A1 mRNA were found. Importantly, when the cells were exposed to DDE and PCB 153 in the presence of an antagonist of tumor necrosis factor (TNF)-α, the over-expression of AhR was abolished; as expected, the expression of CYP1A1 was unaffected. In conclusion, these studies demonstrated for the first time an increment of AhR expression "in vitro" in PBMC treated with two pro-inflammatory environmental pollutants, DDE and PCB153. Moreover, the over-expression of AhR was dependent of TNFα induced by DDE and PCB 153 and was independent of AhR activation.

  3. Suggestions to the media to help us cope with the A/H7N9 crisis in China.

    PubMed

    Sun, Yang; Lu, Hongzhou

    2014-04-01

    The A/H7N9 avian influenza virus sparked global concerns about public health. The media published numerous reports about emerging infectious diseases, including their clinical characteristics and genomic information. However, outbreaks of A/H7N9 posed a real challenge to China's emergency management and especially its dealing with the media. This study analyzes ways to deal with the media during A/H7N9 crises and it proposes a shift in public emergency management from an "Impact-Responsive" approach to a "Prevention-Active" approach. A "Prevention-Active" approach should be used when dealing with the media during subsequent outbreaks.

  4. RhoA GTPase-Induced Ocular Hypertension in a Rodent Model Is Associated with Increased Fibrogenic Activity in the Trabecular Meshwork

    PubMed Central

    Pattabiraman, Padmanabhan P.; Rinkoski, Tommy; Poeschla, Eric; Proia, Alan; Challa, Pratap; Rao, Ponugoti V.

    2016-01-01

    Ocular hypertension arising from increased resistance to aqueous humor (AH) outflow through the trabecular meshwork is a primary risk factor for open-angle glaucoma, a leading cause of blindness. Ongoing efforts have found little about the molecular and cellular bases of increased resistance to AH outflow through the trabecular meshwork in ocular hypertension patients. To test the hypothesis that dysregulated Rho GTPase signaling and a resulting fibrotic activity within the trabecular meshwork may result in ocular hypertension, we investigated the effects of expressing a constitutively active RhoA GTPase (RhoAV14) in the AH outflow pathway in Sprague-Dawley rats by using lentiviral vector-based gene delivery. Rats expressing RhoAV14 in the iridocorneal angle exhibited a significantly elevated intraocular pressure. Elevated intraocular pressure in the RhoAV14-expressing rats was associated with fibrotic trabecular meshwork and increased levels of F-actin, phosphorylated myosin light chain, α-smooth muscle actin, collagen-1A, and total collagen in the trabecular AH outflow pathway. Most of these changes were ameliorated by topical application of Rho kinase inhibitor. Human autopsy eyes from patients with glaucoma exhibited significant increases in levels of collagen-1A and total collagen in the trabecular AH outflow pathway. Collectively, these observations indicate that increased fibrogenic activity because of dysregulated RhoA GTPase activity in the trabecular AH outflow pathway increases intraocular pressure in a Rho kinase-dependent manner. PMID:25499974

  5. Influenza A(H1N1)pdm09 virus in pigs, Togo, 2013

    PubMed Central

    Ducatez, Mariette F.; Awoume, Félix; Webby, Richard J.

    2015-01-01

    We collected 325 nasal swabs from freshly slaughtered previously healthy pigs from October 2012 through January 2014 in a slaughterhouse near Lomé in Togo. Influenza A virus genome was detected by RT-PCR in 2.5% to 12.3% of the pooled samples, and results of hemagglutinin subtyping RT-PCR assays showed the virus in all the positive pools to be A(H1N1)pdm09. Virus was isolated on MDCK cells from a representative specimen, A/swine/Togo/ONA32/2013(H1N1). The isolate was fully sequenced and harbored 8 genes similar to A(H1N1)pdm09 virus genes circulating in humans in 2012–2013, suggesting human-to-swine transmission of the pathogen. PMID:25778544

  6. Schedules of Controlled Substances: Placement of AH-7921 Into Schedule I. Final order.

    PubMed

    2016-04-14

    With the issuance of this final order, the Administrator of the Drug Enforcement Administration places the substance AH-7921 (Systematic IUPAC Name: 3,4-dichloro-N-[(1dimethylamino)cyclohexylmethyl]benzamide), including its isomers, esters, ethers, salts, and salts of isomers, esters and ethers, into schedule I of the Controlled Substances Act. This scheduling action is pursuant to the Controlled Substances Act and is required in order for the United States to discharge its obligations under the Single Convention on Narcotic Drugs, 1961. This action imposes the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances on persons who handle (manufacture, distribute, import, export, engage in research or conduct instructional activities with, or possess), or propose to handle, AH-7921. PMID:27101639

  7. Detecting Polychlorinated Biphenyls by Ah Receptor and Fluorescence Quantitative PCR with Exonuclease

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoxiang; Zhuang, Huisheng

    2010-11-01

    Tetrachlorobiphenyls as ligands were cultivated with goldfish, Ah receptors were extracted from the liver of goldfish and purified by hydroxyapatite. The complex of TCB ligands-receptors were analyzed by Surface Plasmon Resonance. DNA probes were amplified by PCR using Primers F1 and F2 with the DNA recognition site of responsive enhancer. DNA probes bound to the complex were not digested by exonuclease. The DNA that bound to the complex was quantified by real time PCR. A standard curve with TCB concentration to Ct values was obtained in the range of 10-12mol/L to 10-8 mol/L, according to TCB concentration in samples. The detection limit of the assay was below 10-12mol/L of TCB. Compared with HPLC, this assay is much more sensitive. These results suggest that fluorescence quantitative PCR with exonuclease by Ah receptors fits for detection of trace PCB.

  8. Precursor systems analyses of automated highway systems. AHS roadway analysis: Final report. Volume 3. Report for 9 September 1993-30 October 1994

    SciTech Connect

    Elias, J.A.

    1995-05-01

    The programs described by this eight-volume report, a resource materials document type, identified the issues and risks associated with the potential design, development, and operation of an Automated Highway System (AHS), a highway system that utilizes limited access roadways and provides `hands off` driving. The 17 task reports (A through P plus Representative Systems Configurations) are organized into 8 volumes. This volume, which describes roadway analyses, covers four tasks in three chapters. Urban and Rural AHS Analysis (Task A). AHS Roadway Deployment Analysis (Task H), Impact of Non-AHS Roads (Task I), AHS Roadway Operation Analysis (Task K).

  9. MULTIPLE FAST MOLECULAR OUTFLOWS IN THE PRE-PLANETARY NEBULA CRL 618

    SciTech Connect

    Lee, Chin-Fei; Huang, Po-Sheng; Sahai, Raghvendra; Sánchez Contreras, Carmen; Tay, Jeremy Jian Hao

    2013-11-01

    CRL 618 is a well-studied pre-planetary nebula. It has multiple highly collimated optical lobes, fast molecular outflows along the optical lobes, and an extended molecular envelope that consists of a dense torus in the equator and a tenuous round halo. Here we present our observations of this source in CO J = 3-2 and HCN J = 4-3 obtained with the Submillimeter Array at up to ∼0.''3 resolutions. We spatially resolve the fast molecular outflow region previously detected in CO near the central star and find it to be composed of multiple outflows that have similar dynamical ages and are oriented along the different optical lobes. We also detect fast molecular outflows further away from the central star near the tips of the extended optical lobes and a pair of equatorial outflows inside the dense torus. We find that two episodes of bullet ejections in different directions are needed, one producing the fast molecular outflows near the central star and one producing the fast molecular outflows near the tips of the extended optical lobes. One possibility to launch these bullets is a magneto-rotational explosion of the stellar envelope.

  10. The small observed scale of AGN-driven outflows, and inside-out disc quenching

    NASA Astrophysics Data System (ADS)

    Zubovas, Kastytis; King, Andrew

    2016-11-01

    Observations of massive outflows with detectable central active galactic nuclei (AGN) typically find them within radii ≲10 kpc. We show that this apparent size restriction is a natural result of AGN driving if this process injects total energy only of the order of the gas binding energy to the outflow, and the AGN varies over time (`flickers') as suggested in recent work. After the end of all AGN activity, the outflow continues to expand to larger radii, powered by the thermal expansion of the remnant-shocked AGN wind. We suggest that on average, outflows should be detected further from the nucleus in more massive galaxies. In massive gas-rich galaxies, these could be several tens of kpc in radius. We also consider the effect that pressure of such outflows has on a galaxy disc. In moderately gas-rich discs, with gas-to-baryon fraction <0.2, the outflow may induce star formation significant enough to be distinguished from quiescent by an apparently different normalization of the Kennicutt-Schmidt law. The star formation enhancement is probably stronger in the outskirts of galaxy discs, so coasting outflows might be detected by their effects upon the disc even after the driving AGN has shut off. We compare our results to the recent inference of inside-out quenching of star formation in galaxy discs.

  11. Ammonia and CO Outflow around 6.7 GHz Methanol Masers

    NASA Astrophysics Data System (ADS)

    Li, F. C.; Xu, Y.; Wu, Y. W.; Yang, J.; Lu, D. R.; Menten, K. M.; Henkel, C.

    2016-10-01

    Single point observations are presented in NH3 (1, 1) and (2, 2) inversion transitions using the Effelsberg 100 m telescope for a sample of 100 6.7 GHz methanol masers and mapping observations in the 12CO and 13CO (1 ‑ 0) transitions using the Purple Mountain Observatory Delingha 13.7 m telescope for 82 sample sources with detected ammonia. A further 62 sources were selected for either 12CO or 13CO line outflow identification, producing 45 outflow candidates, 29 using 12CO and 16 using 13CO data. Twenty-two of the outflow candidates were newly identified, and 23 had trigonometric parallax distances. Physical properties were derived from ammonia lines and CO outflow parameters were calculated. Histograms and statistical correlations for ammonia, CO outflow parameters, and 6.7 GHz methanol maser luminosities are also presented. No significant correlation was found between ammonia and maser luminosity. However, weak correlations were found between outflow properties and maser luminosities, which may indicate that outflows are physically associated with 6.7 GHz masers.

  12. Endogenous 5-HT outflow from chicken aorta by 5-HT uptake inhibitors and amphetamine derivatives

    PubMed Central

    DELGERMURUN, Dugar; ITO, Shigeo; OHTA, Toshio; YAMAGUCHI, Soichiro; OTSUGURO, Ken-ichi

    2015-01-01

    Chemoreceptor cells aggregating in clusters in the chicken thoracic aorta contain 5-hydroxytryptamine (5-HT) and have voltage-dependent ion channels and nicotinic acetylcholine receptors, which are characteristics typically associated with neurons. The aim of the present study was to investigate the effects of 5-HT uptake inhibitors, fluvoxamine, fluoxetine and clomipramine (CLM), and amphetamine derivatives, p-chloroamphetamine (PCA) and methamphetamine (MET), on endogenous 5-HT outflow from the isolated chick thoracic aorta in vitro. 5-HT was measured by using a HPLC system with electrochemical detection. The amphetamine derivatives and 5-HT uptake inhibitors caused concentration-dependent increases in endogenous 5-HT outflow. PCA was about ten times more effective in eliciting 5-HT outflow than MET. The 5-HT uptake inhibitors examined had similar potency for 5-HT outflow. PCA and CLM increased 5-HT outflow in a temperature-dependent manner. The outflow of 5-HT induced by PCA or 5-HT uptake inhibitors was independent of extracellular Ca2+ concentration. The 5-HT outflow induced by CLM, but not that by PCA, was dependent on the extracellular NaCl concentration. These results suggest that the 5-HT uptake system of 5-HT-containing chemoreceptor cells in the chicken thoracic aorta has characteristics similar to those of 5-HT-containing neurons in the mammalian central nervous system (CNS). PMID:26321443

  13. The Role of Cosmic-Ray Pressure in Accelerating Galactic Outflows

    NASA Astrophysics Data System (ADS)

    Simpson, Christine M.; Pakmor, Rüdiger; Marinacci, Federico; Pfrommer, Christoph; Springel, Volker; Glover, Simon C. O.; Clark, Paul C.; Smith, Rowan J.

    2016-08-01

    We study the formation of galactic outflows from supernova (SN) explosions with the moving-mesh code AREPO in a stratified column of gas with a surface density similar to the Milky Way disk at the solar circle. We compare different simulation models for SN placement and energy feedback, including cosmic rays (CRs), and find that models that place SNe in dense gas and account for CR diffusion are able to drive outflows with similar mass loading as obtained from a random placement of SNe with no CRs. Despite this similarity, CR-driven outflows differ in several other key properties including their overall clumpiness and velocity. Moreover, the forces driving these outflows originate in different sources of pressure, with the CR diffusion model relying on non-thermal pressure gradients to create an outflow driven by internal pressure and the random-placement model depending on kinetic pressure gradients to propel a ballistic outflow. CRs therefore appear to be non-negligible physics in the formation of outflows from the interstellar medium.

  14. Multiple Fast Molecular Outflows in the Pre-planetary Nebula CRL 618

    NASA Astrophysics Data System (ADS)

    Lee, Chin-Fei; Sahai, Raghvendra; Sánchez Contreras, Carmen; Huang, Po-Sheng; Hao Tay, Jeremy Jian

    2013-11-01

    CRL 618 is a well-studied pre-planetary nebula. It has multiple highly collimated optical lobes, fast molecular outflows along the optical lobes, and an extended molecular envelope that consists of a dense torus in the equator and a tenuous round halo. Here we present our observations of this source in CO J = 3-2 and HCN J = 4-3 obtained with the Submillimeter Array at up to ~0.''3 resolutions. We spatially resolve the fast molecular outflow region previously detected in CO near the central star and find it to be composed of multiple outflows that have similar dynamical ages and are oriented along the different optical lobes. We also detect fast molecular outflows further away from the central star near the tips of the extended optical lobes and a pair of equatorial outflows inside the dense torus. We find that two episodes of bullet ejections in different directions are needed, one producing the fast molecular outflows near the central star and one producing the fast molecular outflows near the tips of the extended optical lobes. One possibility to launch these bullets is a magneto-rotational explosion of the stellar envelope.

  15. Paradoxical inhibitory effect of cromakalim on sup 86 Rb outflow from pancreatic islet cells

    SciTech Connect

    Lebrun, P.; Antoine, M.H.; Devreux, V.; Hermann, M.; Herchuelz, A. )

    1990-12-01

    Cromakalim appears to be the most potent pharmacologic agent belonging to the new class of smooth muscle relaxants: the K+ channel openers. The present study aimed at characterizing the effects of cromakalim on 86Rb outflow, 45Ca outflow and insulin release from prelabeled and perifused rat pancreatic islets. Cromakalim provoked a concentration-dependent reduction in 86Rb outflow. This inhibitory effect was attenuated in islets exposed throughout to glibenclamide or to a Ca+(+)-free medium. In islets exposed to glucose and extracellular Ca++, cromakalim induced a dose-dependent reduction in 45Ca outflow. The drug also inhibited the increase in 45Ca outflow mediated by K+ depolarization. Lastly, cromakalim elicited a concentration-dependent inhibition of insulin release from islets perifused in the presence of glucose and extracellular Ca++. The present data suggest that the paradoxical inhibitory effect of cromakalim on 86Rb outflow probably reflects the capacity of the drug to reduce the activity of the ATP-sensitive K+ channels and to indirectly inhibit the Ca+(+)-activated K+ channels. Furthermore, the cromakalim-induced changes in 45Ca outflow are compatible with an inhibitory effect of the drug on the voltage-dependent Ca++ channels.

  16. The Orion Fingers: Near-IR Spectral Imaging of an Explosive Outflow

    NASA Astrophysics Data System (ADS)

    Youngblood, Allison; Ginsburg, Adam; Bally, John

    2016-06-01

    We present near-IR (1.1-2.4 μm) position-position-velocity cubes of the 500 year old Orion BN/KL explosive outflow with spatial resolution 1″ and spectral resolution 86 km s-1. We construct integrated intensity maps free of continuum sources of 15 H2 and [Fe ii] lines while preserving kinematic information of individual outflow features. Included in the detected H2 lines are the 1-0 S(1) and 1-0 Q(3) transitions, allowing extinction measurements across the outflow. Additionally, we present dereddened flux ratios for over two dozen outflow features to allow for the characterization of the true excitation conditions of the BN/KL outflow. All of the ratios show the dominance of the shock excitation of the H2 emission, although some features exhibit signs of fluorescent excitation from stellar radiation or J-type shocks. We also detect tracers of the PDR/ionization front north of the Trapezium stars in [O i] and [Fe ii] and analyze other observed outflows not associated with the BN/KL outflow.

  17. Pathobiological features of a novel, highly pathogenic avian influenza A(H5N8) virus.

    PubMed

    Kim, Young-Il; Pascua, Philippe Noriel Q; Kwon, Hyeok-Il; Lim, Gyo-Jin; Kim, Eun-Ha; Yoon, Sun-Woo; Park, Su-Jin; Kim, Se Mi; Choi, Eun-Ji; Si, Young-Jae; Lee, Ok-Jun; Shim, Woo-Sub; Kim, Si-Wook; Mo, In-Pil; Bae, Yeonji; Lim, Yong Taik; Sung, Moon Hee; Kim, Chul-Joong; Webby, Richard J; Webster, Robert G; Choi, Young Ki

    2014-10-01

    The endemicity of highly pathogenic avian influenza (HPAI) A(H5N1) viruses in Asia has led to the generation of reassortant H5 strains with novel gene constellations. A newly emerged HPAI A(H5N8) virus caused poultry outbreaks in the Republic of Korea in 2014. Because newly emerging high-pathogenicity H5 viruses continue to pose public health risks, it is imperative that their pathobiological properties be examined. Here, we characterized A/mallard duck/Korea/W452/2014 (MDk/W452(H5N8)), a representative virus, and evaluated its pathogenic and pandemic potential in various animal models. We found that MDk/W452(H5N8), which originated from the reassortment of wild bird viruses harbored by migratory waterfowl in eastern China, replicated systemically and was lethal in chickens, but appeared to be attenuated, albeit efficiently transmitted, in ducks. Despite predominant attachment to avian-like virus receptors, MDk/W452(H5N8) also exhibited detectable human virus-like receptor binding and replicated in human respiratory tract tissues. In mice, MDk/W452(H5N8) was moderately pathogenic and had limited tissue tropism relative to previous HPAI A(H5N1) viruses. It also induced moderate nasal wash titers in inoculated ferrets; additionally, it was recovered in extrapulmonary tissues and one of three direct-contact ferrets seroconverted without shedding. Moreover, domesticated cats appeared to be more susceptible than dogs to virus infection. With their potential to become established in ducks, continued circulation of A(H5N8) viruses could alter the genetic evolution of pre-existing avian poultry strains. Overall, detailed virological investigation remains a necessity given the capacity of H5 viruses to evolve to cause human illness with few changes in the viral genome. PMID:26038499

  18. Cellular responses to oxidative stress: The (Ah) gene battery as a paradigm

    SciTech Connect

    Nebert, D.W.; Petersen, D.D.; Fornace, A.J. Jr. )

    1990-08-01

    A major source of oxidative stress in animals is plant stress metabolites, also termed phytoalexins. The aromatic hydrocarbon-responsive (Ah) gene battery is considered here as a model system in which the authors can study metabolically coordinated enzymes that respond to phytoalexin-induced oxidative stress. In the mouse, the (Ah) battery comprises at least six genes: two Phase I genes, CYP1A1 and CYP1A2; and four Phase II genes, Nmo-1, Aldh-1, Ugt-1, and Gt-1. All six genes appear to be regulated positively by inducers such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other ligands of the Ah receptor. The radiation deletion homozygote c{sup 14CoS}/c{sup 14CoS} mouse is lacking about 1.1 centiMorgans of chromosome 7. Although having no detectable CYP1A1 or CYP1A2 activation, the untreated c{sup 14CoS}/c{sup 14CoS} mouse exhibits markedly elevated transcripts of the Nmo-1 gene and three growth arrest- and DNA damage-inducible (gadd) genes. These data suggest that the missing region on chromosome 7 in the c{sup 14Cos}/c{sup 14CoS} mouse contains a gene(s), which they propose to call Nmo-1n, encoding a trans-acting factor(s) that is a negative effector of the Nmo-1 and gadd genes. The three other (Ah) battery Phase II genes behave similarly to Nmo-1 in the c{sup 14CoS}/c{sup 14CoS} mouse. This coordinated response to oxidative stress and DNA damage, by way of the release of a mammalian battery of genes from negative control, bears an interesting resemblance to the SOS response in bacteria.

  19. Equine Influenza A(H3N8) Virus Isolated from Bactrian Camel, Mongolia

    PubMed Central

    Yondon, Myagmarsukh; Zayat, Batsukh; Nelson, Martha I.; Heil, Gary L.; Anderson, Benjamin D.; Lin, Xudong; Halpin, Rebecca A.; McKenzie, Pamela P.; White, Sarah K.; Wentworth, David E.

    2014-01-01

    Because little is known about the ecology of influenza viruses in camels, 460 nasal swab specimens were collected from healthy (no overt illness) Bactrian camels in Mongolia during 2012. One specimen was positive for influenza A virus (A/camel/Mongolia/335/2012[H3N8]), which is phylogenetically related to equine influenza A(H3N8) viruses and probably represents natural horse-to-camel transmission. PMID:25418532

  20. Pathobiological features of a novel, highly pathogenic avian influenza A(H5N8) virus

    PubMed Central

    Kim, Young-Il; Pascua, Philippe Noriel Q; Kwon, Hyeok-Il; Lim, Gyo-Jin; Kim, Eun-Ha; Yoon, Sun-Woo; Park, Su-Jin; Kim, Se Mi; Choi, Eun-Ji; Si, Young-Jae; Lee, Ok-Jun; Shim, Woo-Sub; Kim, Si-Wook; Mo, In-Pil; Bae, Yeonji; Lim, Yong Taik; Sung, Moon Hee; Kim, Chul-Joong; Webby, Richard J; Webster, Robert G; Choi, Young Ki

    2014-01-01

    The endemicity of highly pathogenic avian influenza (HPAI) A(H5N1) viruses in Asia has led to the generation of reassortant H5 strains with novel gene constellations. A newly emerged HPAI A(H5N8) virus caused poultry outbreaks in the Republic of Korea in 2014. Because newly emerging high-pathogenicity H5 viruses continue to pose public health risks, it is imperative that their pathobiological properties be examined. Here, we characterized A/mallard duck/Korea/W452/2014 (MDk/W452(H5N8)), a representative virus, and evaluated its pathogenic and pandemic potential in various animal models. We found that MDk/W452(H5N8), which originated from the reassortment of wild bird viruses harbored by migratory waterfowl in eastern China, replicated systemically and was lethal in chickens, but appeared to be attenuated, albeit efficiently transmitted, in ducks. Despite predominant attachment to avian-like virus receptors, MDk/W452(H5N8) also exhibited detectable human virus-like receptor binding and replicated in human respiratory tract tissues. In mice, MDk/W452(H5N8) was moderately pathogenic and had limited tissue tropism relative to previous HPAI A(H5N1) viruses. It also induced moderate nasal wash titers in inoculated ferrets; additionally, it was recovered in extrapulmonary tissues and one of three direct-contact ferrets seroconverted without shedding. Moreover, domesticated cats appeared to be more susceptible than dogs to virus infection. With their potential to become established in ducks, continued circulation of A(H5N8) viruses could alter the genetic evolution of pre-existing avian poultry strains. Overall, detailed virological investigation remains a necessity given the capacity of H5 viruses to evolve to cause human illness with few changes in the viral genome. PMID:26038499

  1. Relationship between Ah receptor-mediated polychlorinated biphenyl (PCB)-induced humoral immunosuppression and thymic atrophy.

    PubMed

    Silkworth, J B; Antrim, L

    1985-12-01

    Thymic atrophy and humoral immunosuppression by certain polychlorinated biphenyls is associated with the aromatic hydrocarbon (Ah) receptor in mice. We examined the relationship between these two toxic effects. 3,3',4,4'-Tetrachlorobiphenyl (TCB), which causes immunosuppression and thymic atrophy, and 2,3,3',4,4',5-hexachlorobiphenyl, which causes immunosuppression without thymic atrophy, were administered i.p. to C57BL/6 mice at 0, 35 and 350 mumol/kg b.wt. 2 days before i.v. immunization with 10 micrograms of Escherichia coli lipopolysaccharide. Both congeners caused significant suppression of the day 4 anti-lipopolysaccharide plaque-forming cell response/spleen (less than or equal to 46% of control). TCB (350 mumol/kg) was also administered 2 days before either a primary or secondary i.p. immunization with sheep erythrocytes. TCB treatment before primary immunization had no effects on the day 5 secondary response, whereas treatment before the secondary immunization significantly inhibited both day 5 immunoglobulin M and immunoglobulin G plaque-forming cells (less than 10 and less than 2% of control, respectively) and decreased serum antibody. TCB administered either 8 or 2 days before or 2 or 4 days after immunization with sheep erythrocytes demonstrated that significant suppression of both plaque-forming cells and serum antibody could occur without thymic atrophy. Immunity was most impaired when TCB was given 2 days before immunization. These results demonstrate that thymic atrophy does not always accompany the severe immunosuppression caused by Ah receptor ligands and suggests that it may not be a sensitive measure of Ah receptor-mediated immunosuppression. The data also suggests that differentiation of B lymphocytes into antibody producing cells is impaired during Ah receptor-mediated gene activation.

  2. Influenza A(H5N8) virus isolation in Russia, 2014.

    PubMed

    Marchenko, Vasiliy Y; Susloparov, Ivan M; Kolosova, Nataliya P; Goncharova, Nataliya I; Shipovalov, Andrey V; Durymanov, Alexander G; Ilyicheva, Tatyana N; Budatsirenova, Lubov V; Ivanova, Valentina K; Ignatyev, Georgy A; Ershova, Svetlana N; Tulyahova, Valeriya S; Mikheev, Valeriy N; Ryzhikov, Alexander B

    2015-11-01

    In this study, we report the isolation of influenza A(H5N8) virus from a Eurasian wigeon (Anas penelope) in Sakha Republic of the Russian Far East. The strain A/wigeon/Sakha/1/2014 (H5N8) has been shown to be pathogenic for mammals. It is similar to the strains that caused outbreaks in wild birds and poultry in Southeast Asia and Europe in 2014.

  3. Influenza A(H5N8) virus isolation in Russia, 2014.

    PubMed

    Marchenko, Vasiliy Y; Susloparov, Ivan M; Kolosova, Nataliya P; Goncharova, Nataliya I; Shipovalov, Andrey V; Durymanov, Alexander G; Ilyicheva, Tatyana N; Budatsirenova, Lubov V; Ivanova, Valentina K; Ignatyev, Georgy A; Ershova, Svetlana N; Tulyahova, Valeriya S; Mikheev, Valeriy N; Ryzhikov, Alexander B

    2015-11-01

    In this study, we report the isolation of influenza A(H5N8) virus from a Eurasian wigeon (Anas penelope) in Sakha Republic of the Russian Far East. The strain A/wigeon/Sakha/1/2014 (H5N8) has been shown to be pathogenic for mammals. It is similar to the strains that caused outbreaks in wild birds and poultry in Southeast Asia and Europe in 2014. PMID:26306756

  4. Cellular responses to oxidative stress: the [Ah] gene battery as a paradigm.

    PubMed Central

    Nebert, D W; Petersen, D D; Fornace, A J

    1990-01-01

    A major source of oxidative stress in animals is plant stress metabolites, also termed phytoalexins. The aromatic hydrocarbon-responsive [Ah] gene battery is considered here as a model system in which we can study metabolically coordinated enzymes that respond to phytoalexin-induced oxidative stress. In the mouse, the [Ah] battery comprises at least six genes: two Phase I genes, CYP1A1 and CYP1A2; and four Phase II genes, Nmo-1, Aldh-1, Ugt-1, and Gt-1. All six genes appear to be regulated positively by inducers such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other ligands of the Ah receptor. In the absence of foreign inducer, the control of Nmo-1 gene expression is independent of the control of CYP1A1 and CYP1A2 gene expression. The radiation deletion homozygote c14CoS/c14CoS mouse is lacking about 1.1 centiMorgans of chromosome 7. Although having no detectable CYP1A1 or CYP1A2 activation, the untreated c14CoS/c14CoS mouse exhibits markedly elevated transcripts of the Nmo-1 gene and three growth arrest- and DNA damage-inducible (gadd) genes. These data suggest that the missing region on chromosome 7 in the c14CoS/c14CoS mouse contains a gene(s), which we propose to call Nmo-1n, encoding a trans-acting factor(s) that is a negative effector of the Nmo-1 and gadd genes. The three other [Ah] battery Phase II genes behave similarly to Nmo-1 in the c14CoS/c14CoS mouse. This coordinated response to oxidative stress and DNA damage, by way of the release of a mammalian battery of genes from negative control, bears an interesting resemblance to the SOS response in bacteria. PMID:2272308

  5. Lithium-Ion Performance and Abuse Evaluation Using Lithium Technologies 9Ah cell

    NASA Technical Reports Server (NTRS)

    Hall, Albert Daniel; Jeevarajan, Judith A.

    2006-01-01

    Lithium-ion batteries in a pouch form offer high energy density and safety in their designs and more recently they are offering performance at higher rates. Lithium Technologies 9Ah high-power pouch cells were studied at different rates, thermal environments, under vacuum and several different conditions of abuse including overcharge, over-discharge and external short circuit. Results of this study will be presented.

  6. Sinulolides A-H, new cyclopentenone and butenolide derivatives from soft coral Sinularia sp.

    PubMed

    Yang, Bin; Wei, Xiaoyi; Huang, Jingxia; Lin, Xiuping; Liu, Juan; Liao, Shengrong; Wang, Junfeng; Zhou, Xuefeng; Wang, Lishu; Liu, Yonghong

    2014-10-01

    Eight new compounds, sinulolides A-H (1-8), along with two known compounds, α-methoxy-2,3-dimethyl-butenolide (9) and sinularone D (10), were isolated from the soft coral Sinularia sp. The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis. The absolute configurations were determined on the basis of electronic circular dichroism (ECD) data analysis. Compounds 5 and 10 exhibited moderate effects for the inhibition of NF-κB activation.

  7. Episodic molecular outflow in the very young protostellar cluster Serpens South.

    PubMed

    Plunkett, Adele L; Arce, Héctor G; Mardones, Diego; van Dokkum, Pieter; Dunham, Michael M; Fernández-López, Manuel; Gallardo, José; Corder, Stuartt A

    2015-11-01

    The loss of mass from protostars, in the form of a jet or outflow, is a necessary counterpart to protostellar mass accretion. Outflow ejection events probably vary in their velocity and/or in the rate of mass loss. Such 'episodic' ejection events have been observed during the class 0 protostellar phase (the early accretion stage), and continue during the subsequent class I phase that marks the first one million years of star formation. Previously observed episodic-ejection sources were relatively isolated; however, the most common sites of star formation are clusters. Outflows link protostars with their environment and provide a viable source of the turbulence that is necessary for regulating star formation in clusters, but it is not known how an accretion-driven jet or outflow in a clustered environment manifests itself in its earliest stage. This early stage is important in establishing the initial conditions for momentum and energy transfer to the environment as the protostar and cluster evolve. Here we report that an outflow from a young, class 0 protostar, at the hub of the very active and filamentary Serpens South protostellar cluster, shows unambiguous episodic events. The (12)C(16)O (J = 2-1) emission from the protostar reveals 22 distinct features of outflow ejecta, the most recent having the highest velocity. The outflow forms bipolar lobes--one of the first detectable signs of star formation--which originate from the peak of 1-mm continuum emission. Emission from the surrounding C(18)O envelope shows kinematics consistent with rotation and an infall of material onto the protostar. The data suggest that episodic, accretion-driven outflow begins in the earliest phase of protostellar evolution, and that the outflow remains intact in a very clustered environment, probably providing efficient momentum transfer for driving turbulence.

  8. The triggering mechanism and properties of ionized outflows in the nearest obscured quasars

    NASA Astrophysics Data System (ADS)

    Villar Martín, M.; Emonts, B.; Humphrey, A.; Cabrera Lavers, A.; Binette, L.

    2014-06-01

    We have identified ionized outflows in the narrow-line region of all but one Sloan Digital Sky Survey type 2 quasars (QSO2) at z≲0.1 (20/21, detection rate 95 per cent), implying that this is a ubiquitous phenomenon in this object class also at the lowest z. The outflowing gas has high densities (ne≳1000 cm-3) and covers a region the size of a few kpc. This implies ionized outflow masses Moutf ˜ (0.3-2.4) × 106 M⊙ and mass outflow rates Ṁ< few M⊙ yr-1. The triggering mechanism of the outflows is related to the nuclear activity. The QSO2 can be classified into two groups according to the behaviour and properties of the outflowing gas. QSO2 in Group 1 (5/20 objects) show the most extreme turbulence; they have on average higher radio luminosities and higher excess of radio emission. QSO2 in Group 2 (15/20 objects) show less extreme turbulence; they have lower radio luminosities and, on average, lower or no radio excess. We propose that two competing outflow mechanisms are at work: radio jets and accretion disc winds. Radio jet induced outflows are dominant in Group 1, while disc winds dominate in Group 2. We find that the radio jet mode is capable of producing more extreme outflows. To test this interpretation, we predict that (1) high resolution radio imaging will reveal the presence of jets in Group 1 QSO2; (2) the morphology of their extended ionized nebulae must be more highly collimated and kinematically perturbed.

  9. An In Vitro Perfusion System to Enhance Outflow Studies in Mouse Eyes

    PubMed Central

    Kizhatil, Krishnakumar; Chlebowski, Arthur; Tolman, Nicholas G.; Freeburg, Nelson F.; Ryan, Margaret M.; Shaw, Nicholas N.; Kokini, Alexander D. M.; Marchant, Jeffrey K.; John, Simon W. M.

    2016-01-01

    Purpose The molecular mechanisms controlling aqueous humor (AQH) outflow and IOP need much further definition. The mouse is a powerful system for characterizing the mechanistic basis of AQH outflow. To enhance outflow studies in mice, we developed a perfusion system that is based on human anterior chamber perfusion culture systems. Our mouse system permits previously impractical experiments. Methods We engineered a computer-controlled, pump-based perfusion system with a platform for mounting whole dissected mouse eyes (minus lens and iris, ∼45% of drainage tissue is perfused). We tested the system's ability to monitor outflow and tested the effects of the outflow-elevating drug, Y27632, a rho-associated protein kinase (ROCK) inhibitor. Finally, we tested the system's ability to detect genetically determined decreases in outflow by determining if deficiency of the candidate genes Nos3 and Cav1 alter outflow. Results Using our system, the outflow facility (C) of C57BL/6J mouse eyes was found to range between 7.7 and 10.4 nl/minutes/mm Hg (corrected for whole eye). Our system readily detected a 74.4% Y27632-induced increase in C. The NOS3 inhibitor L-NG-nitroarginine methyl ester (L-NAME) and a Nos3 null mutation reduced C by 28.3% and 35.8%, respectively. Similarly, in Cav1 null eyes C was reduced by 47.8%. Conclusions We engineered a unique perfusion system that can accurately measure changes in C. We then used the system to show that NOS3 and CAV1 are key components of mechanism(s) controlling outflow. PMID:27701632

  10. Massive Stellar Outflows From the Combined Action of Multiple Stellar Jets

    NASA Astrophysics Data System (ADS)

    Mac Low, Mordecai-Mark; Peters, T.; Klaassen, P.; Schrön, M.; Klessen, R.

    2014-01-01

    The formation of high-mass stars is usually accompanied by powerful protostellar outflows. Such high-mass outflows are not simply scaled-up versions of their lower-mass counterparts, since observations seem to suggest that the collimation degree degrades with stellar mass. Theoretically, the origins of massive outflows are not well understood because radiative feedback and gravitational fragmentation of the accretion flow around the high-mass star impede the driving of magnetic disk winds. We here present the first 3D simulation of massive star formation that simultaneously includes feedback by non-ionizing and ionizing radiation as well as a subgrid-scale model for protostellar outflows. We ran this model with the Flash adaptive mesh refinement hydrocode. We find that stars that form in a common accretion flow have aligned outflow axes, so that the individual jets of lower-mass companion stars combine to form a collective outflow. We compare our simulation to observations with synthetic H2 and CO observations and find that the morphology and kinematics of this collective outflow is very similar to observed massive outflows, such as Cepheus A and DR 21. The properties of high-mass outflows are therefore generally consistent with the formation of massive stars in gravitationally unstable accretion flows. We acknowledge support from SNF grant 200020 137896, U. Zurich grant FK-13-112, NSF grant AST11-09395, and DFG grant KL 1358/14-1, as well as SBB 811, and computing time at the LRZ (project h1343), the CSCS (Project 364), and the Juelich Supercomputing Center (project HHD14).

  11. Episodic molecular outflow in the very young protostellar cluster Serpens South.

    PubMed

    Plunkett, Adele L; Arce, Héctor G; Mardones, Diego; van Dokkum, Pieter; Dunham, Michael M; Fernández-López, Manuel; Gallardo, José; Corder, Stuartt A

    2015-11-01

    The loss of mass from protostars, in the form of a jet or outflow, is a necessary counterpart to protostellar mass accretion. Outflow ejection events probably vary in their velocity and/or in the rate of mass loss. Such 'episodic' ejection events have been observed during the class 0 protostellar phase (the early accretion stage), and continue during the subsequent class I phase that marks the first one million years of star formation. Previously observed episodic-ejection sources were relatively isolated; however, the most common sites of star formation are clusters. Outflows link protostars with their environment and provide a viable source of the turbulence that is necessary for regulating star formation in clusters, but it is not known how an accretion-driven jet or outflow in a clustered environment manifests itself in its earliest stage. This early stage is important in establishing the initial conditions for momentum and energy transfer to the environment as the protostar and cluster evolve. Here we report that an outflow from a young, class 0 protostar, at the hub of the very active and filamentary Serpens South protostellar cluster, shows unambiguous episodic events. The (12)C(16)O (J = 2-1) emission from the protostar reveals 22 distinct features of outflow ejecta, the most recent having the highest velocity. The outflow forms bipolar lobes--one of the first detectable signs of star formation--which originate from the peak of 1-mm continuum emission. Emission from the surrounding C(18)O envelope shows kinematics consistent with rotation and an infall of material onto the protostar. The data suggest that episodic, accretion-driven outflow begins in the earliest phase of protostellar evolution, and that the outflow remains intact in a very clustered environment, probably providing efficient momentum transfer for driving turbulence. PMID:26536957

  12. Radiation-hydrodynamic Simulations of Massive Star Formation with Protostellar Outflows

    NASA Astrophysics Data System (ADS)

    Cunningham, Andrew J.; Klein, Richard I.; Krumholz, Mark R.; McKee, Christopher F.

    2011-10-01

    We report the results of a series of adaptive mesh refinement radiation-hydrodynamic simulations of the collapse of massive star-forming clouds using the ORION code. These simulations are the first to include the feedback effects protostellar outflows, as well as protostellar radiative heating and radiation pressure exerted on the infalling, dusty gas. We find that outflows evacuate polar cavities of reduced optical depth through the ambient core. These enhance the radiative flux in the poleward direction so that it is 1.7-15 times larger than that in the midplane. As a result the radiative heating and outward radiation force exerted on the protostellar disk and infalling cloud gas in the equatorial direction are greatly diminished. This simultaneously reduces the Eddington radiation pressure barrier to high-mass star formation and increases the minimum threshold surface density for radiative heating to suppress fragmentation compared to models that do not include outflows. The strength of both these effects depends on the initial core surface density. Lower surface density cores have longer free-fall times and thus massive stars formed within them undergo more Kelvin contraction as the core collapses, leading to more powerful outflows. Furthermore, in lower surface density clouds the ratio of the time required for the outflow to break out of the core to the core free-fall time is smaller, so that these clouds are consequently influenced by outflows at earlier stages of the collapse. As a result, outflow effects are strongest in low surface density cores and weakest in high surface density ones. We also find that radiation focusing in the direction of outflow cavities is sufficient to prevent the formation of radiation pressure-supported circumstellar gas bubbles, in contrast to models which neglect protostellar outflow feedback.

  13. Radiation-Hydrodynamic Simulations of Massive Star Formation with Protostellar Outflows

    SciTech Connect

    Cunningham, A J; Klein, R I; Krumholz, M R; McKee, C F

    2011-03-02

    We report the results of a series of AMR radiation-hydrodynamic simulations of the collapse of massive star forming clouds using the ORION code. These simulations are the first to include the feedback effects protostellar outflows, as well as protostellar radiative heating and radiation pressure exerted on the infalling, dusty gas. We find that that outflows evacuate polar cavities of reduced optical depth through the ambient core. These enhance the radiative flux in the poleward direction so that it is 1.7 to 15 times larger than that in the midplane. As a result the radiative heating and outward radiation force exerted on the protostellar disk and infalling cloud gas in the equatorial direction are greatly diminished. The simultaneously reduces the Eddington radiation pressure barrier to high-mass star formation and increases the minimum threshold surface density for radiative heating to suppress fragmentation compared to models that do not include outflows. The strength of both these effects depends on the initial core surface density. Lower surface density cores have longer free-fall times and thus massive stars formed within them undergo more Kelvin contraction as the core collapses, leading to more powerful outflows. Furthermore, in lower surface density clouds the ratio of the time required for the outflow to break out of the core to the core free-fall time is smaller, so that these clouds are consequently influenced by outflows at earlier stages of collapse. As a result, outflow effects are strongest in low surface density cores and weakest in high surface density one. We also find that radiation focusing in the direction of outflow cavities is sufficient to prevent the formation of radiation pressure-supported circumstellar gas bubbles, in contrast to models which neglect protostellar outflow feedback.

  14. Changes in the Composition of the Fram Strait Freshwater Outflow

    NASA Astrophysics Data System (ADS)

    Dodd, Paul; Granskog, Mats; Fransson, Agneta; Chierici, Melissa; Stedmon, Colin

    2016-04-01

    Fram Strait is the largest gateway and only deep connection between the Arctic Ocean and the subpolar oceans. Monitoring the exchanges through Fram Strait allows us to detect and understand current changes occurring in the Arctic Ocean and to predict the effects of those changes on the Arctic and Subarctic climate and ecosystems. Polar water, recirculating Atlantic Water and deeper water masses exported from the Arctic Ocean through western Fram Strait are monitored year-round by an array of moored instruments along 78°50'N, continuously maintained by the Norwegian Polar Institute since the 1990s. Complimentary annual hydrographic sections have been repeated along the same latitude every September. This presentation will focus on biogeochemical tracer measurements collected along repeated sections from 1997-2015, which can be used to identify freshwater from different sources and reveal the causes of variations in total volume of freshwater exported e. g.: pulses of freshwater from the Pacific. Repeated tracer sections across Fram Strait reveal significant changes in the composition of the outflow in recent years, with recent sections showing positive fractions of sea ice meltwater at the surface near the core of the EGC, suggesting that more sea ice melts back into the surface than previously. The 1997-2015 time series of measurements reveals a strong anti-correlation between run-off and net sea ice meltwater inventories, suggesting that run-off and brine may be delivered to Fram Strait together from a common source. While the freshwater outflow at Fram Strait typically exhibits a similar run-off to net sea ice meltwater ratio to the central Arctic Ocean and Siberian shelves, we find that the ratio of run-off to sea ice meltwater at Fram Strait is decreasing with time, suggesting an increased surface input of sea ice meltwater in recent years. In 2014 and 2015 measurements of salinity, δ18O and total alkalinity were collected from sea ice cores as well as the

  15. Renal AH Amyloidosis Associated With a Truncated Immunoglobulin Heavy Chain Undetectable by Immunostaining.

    PubMed

    Manabe, Shun; Hatano, Michiyasu; Yazaki, Masahide; Nitta, Kosaku; Nagata, Michio

    2015-12-01

    AH amyloidosis is a rare type of amyloidosis caused by deposition of monoclonal immunoglobulin heavy chain. The key diagnostic feature is positive immunostaining for a single class of immunoglobulin heavy chain. We report a case of AH amyloidosis with immunoglobulin G (IgG) λ monoclonal gammopathy that was diagnosed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) after immunostaining of renal tissue for immunoglobulin heavy chain gave negative results. The molecular weight of the purified renal amyloid protein was ∼11kDa, which was determined by LC-MS/MS analysis to correspond to an amino acid sequence comprising the variable region and a truncated portion of the constant region of IgG heavy chain. The exact same truncated heavy chain was detected by LC-MS/MS of a protein isolated from the patient's serum, suggesting that the truncated serum protein was the precursor of the amyloid protein. Because antibodies to immunoglobulin heavy chain recognize the Fc portion, the large deletion in the constant region could explain the negative results upon immunostaining. Direct protein detection by LC-MS/MS is a powerful aid to diagnose renal AH amyloidosis, particularly when the findings of immunoglobulin staining are inconsistent with the background monoclonal gammopathy.

  16. Adaptation of influenza A(H1N1)pdm09 virus in experimental mouse models.

    PubMed

    Prokopyeva, E A; Sobolev, I A; Prokopyev, M V; Shestopalov, A M

    2016-04-01

    In the present study, three mouse-adapted variants of influenza A(H1N1)pdm09 virus were obtained by lung-to-lung passages of BALB/c, C57BL/6z and CD1 mice. The significantly increased virulence and pathogenicity of all of the mouse-adapted variants induced 100% mortality in the adapted mice. Genetic analysis indicated that the increased virulence of all of the mouse-adapted variants reflected the incremental acquisition of several mutations in PB2, PB1, HA, NP, NA, and NS2 proteins. Identical amino acid substitutions were also detected in all of the mouse-adapted variants of A(H1N1)pdm09 virus, including PB2 (K251R), PB1 (V652A), NP (I353V), NA (I106V, N248D) and NS1 (G159E). Apparently, influenza A(H1N1)pdm09 virus easily adapted to the host after serial passages in the lungs, inducing 100% lethality in the last experimental group. However, cross-challenge revealed that not all adapted variants are pathogenic for different laboratory mice. Such important results should be considered when using the influenza mice model.

  17. Adaptation of influenza A(H1N1)pdm09 virus in experimental mouse models.

    PubMed

    Prokopyeva, E A; Sobolev, I A; Prokopyev, M V; Shestopalov, A M

    2016-04-01

    In the present study, three mouse-adapted variants of influenza A(H1N1)pdm09 virus were obtained by lung-to-lung passages of BALB/c, C57BL/6z and CD1 mice. The significantly increased virulence and pathogenicity of all of the mouse-adapted variants induced 100% mortality in the adapted mice. Genetic analysis indicated that the increased virulence of all of the mouse-adapted variants reflected the incremental acquisition of several mutations in PB2, PB1, HA, NP, NA, and NS2 proteins. Identical amino acid substitutions were also detected in all of the mouse-adapted variants of A(H1N1)pdm09 virus, including PB2 (K251R), PB1 (V652A), NP (I353V), NA (I106V, N248D) and NS1 (G159E). Apparently, influenza A(H1N1)pdm09 virus easily adapted to the host after serial passages in the lungs, inducing 100% lethality in the last experimental group. However, cross-challenge revealed that not all adapted variants are pathogenic for different laboratory mice. Such important results should be considered when using the influenza mice model. PMID:26829383

  18. Long life 80Ah standard IPV NiH2 battery cell

    NASA Astrophysics Data System (ADS)

    Armantrout, Jon D.; Waller, J. S.

    1995-02-01

    A standard Nickel-Hydrogen (NiH2) Individual Pressure Vessel (IPV) battery cell is needed to meet future low cost, high performance mission requirements for NASA, military, and civil space programs. A common or standard cell design has evolved from the heritage of HST, Milstar, and other Air Force Mantech cell designs with substantial flight experience, while incorporating some of the historical COMSAT cell design features described in a previous NASA publication. Key features include slurry process nickel electrodes having high strength, long life and high yield (lower cost), and dual layer zircar separators for improved KOH retention, uniformality, and longer life. The cell design will have a zirconium oxide wall wick inside the pressure vessel to redistribute electrolyte and extend life. The slurry electrode will be 35 mils thick to take advantage of qualified cell mechanical configurations and proven assembly and activation techniques developed by Eagle Picher Industries (EPI) for the Hubble Space Telescope (HST) RNH-90-3 and 'Generic HST' RNH-90-5 cell designs with back-to-back nickel electrodes produced by the dry sinter process. The 80Ah common cell design can be scaled to meet capacity requirements from 60Ah to 100Ah. Producibility, commonality, and long life performance will be enhanced with the robust cell design described herein.

  19. Human Antibody Responses to Avian Influenza A(H7N9) Virus, 2013

    PubMed Central

    Guo, Li; Zhang, Xi; Ren, Lili; Yu, Xuelian; Chen, Lijuan; Zhou, Hongli; Gao, Xin; Teng, Zheng; Li, Jianguo; Hu, Jiayu; Wu, Chao; Xiao, Xia; Zhu, Yiyi; Wang, Quanyi; Pang, Xinghuo; Jin, Qi; Wu, Fan

    2014-01-01

    Understanding host antibody response is crucial for predicting disease severity and for vaccine development. We investigated antibody responses against influenza A(H7N9) virus in 48 serum samples from 21 patients, including paired samples from 15 patients. IgG against subtype H7 and neutralizing antibodies (NAbs) were not detected in acute-phase samples, but ELISA geometric mean titers increased in convalescent-phase samples; NAb titers were 20–80 (geometric mean titer 40). Avidity to IgG against subtype H7 was significantly lower than that against H1 and H3. IgG against H3 was boosted after infection with influenza A(H7N9) virus, and its level in acute-phase samples correlated with that against H7 in convalescent-phase samples. A correlation was also found between hemagglutinin inhibition and NAb titers and between hemagglutinin inhibition and IgG titers against H7. Because of the relatively weak protective antibody response to influenza A(H7N9), multiple vaccinations might be needed to achieve protective immunity. PMID:24447423

  20. Long life 80Ah standard IPV NiH2 battery cell

    NASA Technical Reports Server (NTRS)

    Armantrout, Jon D.; Waller, J. S.

    1995-01-01

    A standard Nickel-Hydrogen (NiH2) Individual Pressure Vessel (IPV) battery cell is needed to meet future low cost, high performance mission requirements for NASA, military, and civil space programs. A common or standard cell design has evolved from the heritage of HST, Milstar, and other Air Force Mantech cell designs with substantial flight experience, while incorporating some of the historical COMSAT cell design features described in a previous NASA publication. Key features include slurry process nickel electrodes having high strength, long life and high yield (lower cost), and dual layer zircar separators for improved KOH retention, uniformality, and longer life. The cell design will have a zirconium oxide wall wick inside the pressure vessel to redistribute electrolyte and extend life. The slurry electrode will be 35 mils thick to take advantage of qualified cell mechanical configurations and proven assembly and activation techniques developed by Eagle Picher Industries (EPI) for the Hubble Space Telescope (HST) RNH-90-3 and 'Generic HST' RNH-90-5 cell designs with back-to-back nickel electrodes produced by the dry sinter process. The 80Ah common cell design can be scaled to meet capacity requirements from 60Ah to 100Ah. Producibility, commonality, and long life performance will be enhanced with the robust cell design described herein.

  1. Physicochemical Properties and Surfaces Morphologies Evaluation of MTA FillApex and AH Plus

    PubMed Central

    Borges, Álvaro Henrique; Orçati Dorileo, Maura Cristiane Gonçales; Villa, Ricardo Dalla; Borba, Alexandre Meireles; Semenoff, Tereza Aparecida Delle Vedove; Guedes, Orlando Aguirre; Estrela, Cyntia Rodrigues Araújo; Bandeca, Matheus Coelho

    2014-01-01

    The solubility, pH, electrical conductivity, and radiopacity of AH Plus and MTA FillApex were evaluated. In addition, the surfaces morphologies of the sealers were analyzed by using scanning electron microscopy. For pH test, the samples were immersed in distilled water at different periods of time. The same solution was used for electrical conductivity measurement. The solubility and radiopacity were evaluated according to ANSI/ADA. Statistical analyses were carried out at 5% level of significance. MTA FillApex presented higher mean value for solubility and electrical conductivity. No significant difference was observed in the mean values for pH reading. AH Plus presented higher radiopacity mean values. MTA FillApex presented an external surface with porosities and a wide range of sizes. In conclusion, the materials fulfill the ANSI/ADA requirements when considering the radiopacity and solubility. AH Plus revealed a compact and homogeneous surface with more regular aspects and equal particle sizes. PMID:24883413

  2. A generalized dynamic balancing procedure for the AH-64 tail rotor

    NASA Astrophysics Data System (ADS)

    Kunz, Donald L.; Newkirk, Mark C.

    2009-09-01

    The tail rotors on the AH-64A Apache and AH-64D Longbow Apache incorporate a unique design, which includes two, two-bladed teetering rotors that have an azimuth spacing of 55°, instead of the more usual 90°. Maintainers have observed that some Apache tail rotors can be extraordinarily difficult to balance dynamically. This investigation uses RCAS (Rotorcraft Comprehensive Analysis System) numerical simulations of tail rotor response when mass is added to the tips of single and adjacent blades to investigate possible causes for this balancing difficulty. The simulations show that the 1/rev, vertical, vibratory force response due to added tip mass varies as a function of the mass distribution between two adjacent blades, and the azimuth spacing between the two blades. As a result, the tail rotor balance sensitivity coefficients, if used as for a single blade, will be inaccurate; and may be a prime contributor to the problems observed while balancing tail rotors. An analytical model of the AH-64D tail rotor, with characteristics similar to the RCAS model, and which incorporates the influence of structural impedance through the balance sensitivity coefficients and phase angles, is used to develop a method for accurately determining the amount of tip mass required to reduce the 1/rev vibrations to acceptable levels.

  3. A novel AhR ligand, 2AI, protects the retina from environmental stress

    PubMed Central

    Gutierrez, Mark A.; Davis, Sonnet S.; Rosko, Andrew; Nguyen, Steven M.; Mitchell, Kylie P.; Mateen, Samiha; Neves, Joana; Garcia, Thelma Y.; Mooney, Shaun; Perdew, Gary H.; Hubbard, Troy D.; Lamba, Deepak A.; Ramanathan, Arvind

    2016-01-01

    Various retinal degenerative diseases including dry and neovascular age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy are associated with the degeneration of the retinal pigmented epithelial (RPE) layer of the retina. This consequently results in the death of rod and cone photoreceptors that they support, structurally and functionally leading to legal or complete blindness. Therefore, developing therapeutic strategies to preserve cellular homeostasis in the RPE would be a favorable asset in the clinic. The aryl hydrocarbon receptor (AhR) is a conserved, environmental ligand-dependent, per ARNT-sim (PAS) domain containing bHLH transcription factor that mediates adaptive response to stress via its downstream transcriptional targets. Using in silico, in vitro and in vivo assays, we identified 2,2′-aminophenyl indole (2AI) as a potent synthetic ligand of AhR that protects RPE cells in vitro from lipid peroxidation cytotoxicity mediated by 4-hydroxynonenal (4HNE) as well as the retina in vivo from light-damage. Additionally, metabolic characterization of this molecule by LC-MS suggests that 2AI alters the lipid metabolism