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Sample records for abundant igg4-positive plasma

  1. Refractory gastric ulcer with abundant IgG4-positive plasma cell infiltration: A case report

    Institute of Scientific and Technical Information of China (English)

    Takayoshi; Fujita; Takafumi; Ando; Masatoshi; Sakakibara; Waki; Hosoda; Hidemi; Goto

    2010-01-01

    We describe a 77-year-old man with refractory gastric ulcer that worsened after Helicobacter pylori eradication therapy.Pathology showed marked infiltration of IgG4-positive plasma cells in the gastric lesions,which led us to suspect IgG4-related sclerosing disease.To the best of our knowledge,this is the first report of IgG4-related gastric ulcer without the main manifestation of autoimmune pancreatitis.

  2. Autoimmune pancreatitis metachronously associated with retroperitoneal fibrosis with IgG4-positive plasma cell infiltration

    Institute of Scientific and Technical Information of China (English)

    Terumi Kamisawa; Pong Yui Chen; Yuyang Tu; Hitoshi Nakajima; Naoto Egawa

    2006-01-01

    Retroperitoneal fibrosis is an uncommon disorder characterized by the formation of a dense plaque of fibrous tissue in the retroperitoneum, and its etiology remains unknown. Autoimmune pancreatitis is a rare type of chronic pancreatitis characterized by fibrosis with abundant infiltration of IgG4-positive plasma cells and lymphocytes and obliterative phlebitis in the pancreas. We present a case of autoimmune pancreatitis that developed 10 mo after the occurrence of retroperitoneal fibrosis. Histological findings of the resected retroperitoneal mass were marked periureteral fibrosis with abundant infiltration of IgG4-positive plasma cells and lymphocytes and obliterative phlebitis.These findings suggest a common pathophysiological mechanism for retroperitoneal fibrosis and autoimmune pancreatitis in this case. Some cases of retroperitoneal fibrosis might be a retroperitoneal lesion of IgG4-related sclerosing disease.

  3. Oral lichen sclerosus expressing extracellular matrix proteins and IgG4-positive plasma cells.

    Science.gov (United States)

    De Aquino Xavier, Flavia Calo; Prates, Alisio Alves; Gurgel, Clarissa Araujo; De Souza, Tulio Geraldo; Andrade, Rodrigo Guimaraes; Goncalves Ramos, Eduardo Antonio; Pedreira Ramalho, Luciana Maria; Dos Santos, Jean Nunes

    2014-09-16

    Lichen sclerosus (LS) is a mucocutaneous disease with uncommon oral involvement. The etiology is not yet well understood, but LS has been associated with autoimmune, genetic, and immunological factors. We report a 47-year-old man with LS that exhibited an asymptomatic white plaque with red patches on the maxillary alveolar mucosa extending to the labial mucosa. He had no other skin disease. Positive immunostaining for tenascin and scarcity of fibronectin suggested extracellular matrix reorganization. Elastin immunostaining indicated a reduction of elastic fibers. Immunoexpression of collagen IV in blood vessels and its absence in the epithelial basement membrane, together with diffuse MMP-9 immunoexpression, suggested altered proteolytic activity. Mast cell staining bordering areas of sclerosis indicated a possible role in the synthesis of collagen. IgG4 positivity in plasma cells suggested a role in the fibrogenesis. This is an unusual presentation of oral LS and we discuss immunohistochemical findings regarding cellular and extracellular matrix components.

  4. Autoimmune pancreatitis with IgG4-positive plasma cell infiltration in salivary glands and biliary tract

    Institute of Scientific and Technical Information of China (English)

    Masashi Taguchi; Gentaro Aridome; Shintaro Abe; Keiichiro Kume; Mitsuo Tashiro; Mitsuyoshi Yamamoto; Yasuyuki Kihara; Hayato Nakamura; Makoto Otsuki

    2005-01-01

    A 62-year-old male was referred to our hospital because of liver dysfunction, diffuse pancreatic swelling, and trachelophyma. At admission, the patient was free of pain.Physical examination showed enlarged and palpable bilateral submandibular masses, but no palpable mass or organomegaly in the abdomen. Laboratory findings were as follows: total protein 90 g/L with γ-globulin of 37.3% (33 g/L), total bilirubin 4 mg/L, aspartate aminotransferase 39 IU/L, alanine aminotransferase 67 IU/L, γ-glutamyl transpeptidase 1 647 IU/L, and amylase 135 IU/L. Autoantibodies were negative, and tumor markers were within the normal range. Serum IgG4 level was markedly elevated (18 900 mg/L). Computed tomography (CT) showed diffuse swelling of the pancreas and dilatation of both common and intra-hepatic bile ducts. Endoscopic retrograde pancreatography (ERP) revealed diffuse irregular and narrow main pancreatic duct and stenosis of the lower common bile duct. Biopsy specimens from the pancreas, salivary gland and liver showed marked periductal IgG4-positive plasma cell infiltration with fibrosis. We considered this patient to be autoimmune pancreatitis (AIP) with fibrosclerosis of the salivary gland and biliary tract, prescribed prednisolone at an initial dose of 40 mg/d. Three months later, the laboratory data improved almost to normal. Abdominal CT reflected prominent improvement in the pancreatic lesion. Swelling of the salivary gland also improved. At present, the patient is on 10 mg/d of prednisolone without recurrence of the pancreatitis. We present here a case of AIP with fibrosclerosis of salivary gland and biliary tract.

  5. Hepatic nodular lymphoid lesion with increased IgG4-positive plasma cells associated with primary biliary cirrhosis: a report of two cases.

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    Calvo, Jessica; Carbonell, Nicolas; Scatton, Olivier; Marzac, Christophe; Ganne-Carrie, Nathalie; Wendum, Dominique

    2015-11-01

    The nodular lymphoid lesion of the liver known as reactive lymphoid hyperplasia or pseudolymphoma is rare and its pathogenesis is unknown. We report two cases of nodular lymphoid lesions of the liver with numerous IgG4-positive plasma cells in patients with primary biliary cirrhosis. Histologically, in both cases, the lesion showed a dense lymphoplasmacytic infiltrate with lymphoid follicles and granulomas. Fibrous tissue was scarce and without a storiform pattern. Obliterative phlebitis was not identified. The IgG4+ plasma cell counts were 82 and 76 per high power field, with an IgG4/IgG ratio of 75 and 64 %, respectively, which qualifies the lesions according to the diagnostic criteria for IgG4-related disease as « probable histological feature of IgG4-related disease ». There were no rearrangements of immunoglobulin heavy-chain genes and plasma cells had a polytypic pattern of kappa and lambda light-chain expression. The non-tumor liver showed primary biliary cirrhosis with destructive cholangitis without IgG4 plasma cells. In both cases, IgG4-related disease was not found in other organs neither at the time of diagnosis nor 3 years later. Serum IgG4 levels normalized after local ablation of the lesions. It seems unlikely that these lesions are a manifestation of IgG4-related disease. However, because the pathogenesis of both nodular lymphoid lesions and IgG4-related disease remains unclear, further studies are needed to elucidate a potential link between nodular lymphoid lesions of the liver and an increased number of IgG4 plasma cells. More definite conclusions will be possible when the pathogenesis of IgG4-related disease has been clarified.

  6. 18F-fluoro-deoxyglucose positron emission tomography/computed tomography scan findings in Rosai-Dorfman disease with IgG4-positive plasma cell infiltration mimicking breast malignancy: a case report and literature review

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    Fu Liping

    2012-11-01

    Full Text Available Abstract Introduction Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare benign disorder characterized histologically by lymphatic sinus dilatation due to histiocyte proliferation. Rosai-Dorfman disease accompanied by IgG4+ plasma cell infiltration is an even rarer situation. To the best of our knowledge, no imaging report of fluoro-deoxyglucose positron emission tomography/computed tomography findings of Rosai-Dorfman disease with IgG4+ plasma cell infiltration has been published, although a series of pathological research has focused on this phenomenon. Case presentation We reviewed the 18F-fluoro-deoxyglucose positron emission tomography/computed tomography scan of a 78-year-old Chinese woman with a solid mass that was found in her right breast during a health checkup. 18F-fluoro-deoxyglucose positron emission tomography/computed tomography showed a hypermetabolic nodule in her right breast and slightly heterogeneous increased fluoro-deoxyglucose uptake of the pulmonary nodules, which were histologically proven to be mammary Rosai-Dorfman disease with IgG4+ plasma cell infiltration and pulmonary amyloidosis, respectively. A literature review was performed to gather information on this rare disease process. Conclusions Although distinguishing benign lymphoplasmacytic proliferation from malignancy may be difficult with 18F-fluoro-deoxyglucose positron emission tomography/computed tomography in light of the pattern and intensity of fluoro-deoxyglucose uptake, our case highlights that whole-body positron emission tomography/computed tomography imaging not only can display the extent of the disease to help complete staging but also can provide functional information about disease activity to guide biopsy.

  7. A high number of IgG4-positive cells in gastric cancer tissue is associated with tumor progression and poor prognosis.

    Science.gov (United States)

    Miyatani, Kozo; Saito, Hiroaki; Murakami, Yuki; Watanabe, Joji; Kuroda, Hirohiko; Matsunaga, Tomoyuki; Fukumoto, Yoji; Osaki, Tomohiro; Nakayama, Yuji; Umekita, Yoshihisa; Ikeguchi, Masahide

    2016-05-01

    IgG4-related disease is a newly defined disease characterized by elevated serum IgG4 levels and infiltration of affected organs by IgG4-positive plasma cells. Recently, increased IgG4 levels were reported to be closely related with malignancy. To assess the relationship between IgG4 and the progression of gastric cancer, we immunohistochemically stained in this study gastric cancer tissue samples for IgG4-positive cells using an anti-IgG4 antibody. In addition, pre- and postoperative serum concentrations of IgG4 were measured, using an enzyme-linked immunosorbent assay. In gastric cancer samples, the number of CD138-positive plasma cells was significantly lower and the number of IgG4-positive cells significantly higher than in non-cancerous gastric mucosa. The number of IgG4-positive cells was significantly correlated with gross tumor appearance, tumor depth, lymph node metastasis, venous invasion, and lymphatic invasion. Prognosis was significantly poorer in patients with a high number of IgG4-positive cells than in those with a low number. Multivariate analysis indicated that both the number of IgG4-positive cells and the depth of tumor invasion were independently prognostic of survival. In conclusion, in gastric cancer, the number of IgG4-positive cells is increased and this is closely associated with gastric cancer progression.

  8. Flare Plasma Iron Abundance

    Science.gov (United States)

    Dennis, Brian R.; Dan, Chau; Jain, Rajmal; Schwartz, Richard A.; Tolbert, Anne K.

    2008-01-01

    The equivalent width of the iron-line complex at 6.7 keV seen in flare X-ray spectra suggests that the iron abundance of the hottest plasma at temperatures >approx.10 MK may sometimes be significantly lower than the nominal coronal abundance of four times the photospheric value that is commonly assumed. This conclusion is based on X-ray spectral observations of several flares seen in common with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Solar X-ray Spectrometer (SOXS) on the second Indian geostationary satellite, GSAT-2. The implications of this will be discussed as it relates to the origin of the hot flare plasma - either plasma already in the corona that is directly heated during the flare energy release process or chromospheric plasma that is heated by flare-accelerated particles and driven up into the corona. Other possible explanations of lower-than-expected equivalent widths of the iron-line complex will also be discussed.

  9. Increased IgG4-Positive Plasma Cells in Granulomatosis with Polyangiitis: A Diagnostic Pitfall of IgG4-Related Disease

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    Sing Yun Chang

    2012-01-01

    Full Text Available Granulomatosis with polyangiitis (Wegener’s (GPA may mimic IgG4-related disease (IgG4-RD on histologic examination of some biopsies, especially those from head and neck sites. IgG4 immunostain is often performed in this context for differential diagnosis with IgG4-RD. However, the prevalence of IgG4+ cells in GPA has not been explored. We examined the IgG4+ cells in 26 cases confirmed as GPA by a thorough clinical and pathologic assessment. Twenty-six biopsies consisted of 14 sinonasal/oral cavity/nasopharynx, 7 orbit/periorbital, 3 lung/pleura, 1 iliac fossa/kidney, and 1 dura specimens. Eight of 26 (31% biopsies revealed increased IgG4+ cells (>30/HPF and >40% in IgG4+/IgG+ ratio. The IgG4+ cells and IgG4+/IgG+ ratio ranged 37–137/hpf and 44–83%, respectively. Eight biopsies with increased IgG4+ cells were from sinonasal (n=4 or orbital/periorbital (n=4 sites. In conclusion, increased IgG4+ cells are not uncommonly seen in sinonasal or orbital/periorbital biopsies of GPA, which could pose as a diagnostic pitfall.

  10. Chemical Fractionation and Abundances in Coronal Plasma

    CERN Document Server

    Drake, J J

    2003-01-01

    Much of modern astrophysics is grounded on the observed chemical compositions of stars and the diffuse plasma that pervades the space between stars, galaxies and clusters of galaxies. X-ray and EUV spectra of the hot plasma in the outer atmospheres of stars have demonstrated that these environments are subject to chemical fractionation in which the abundances of elements can be enhanced and depleted by an order of magnitude or more. These coronal abundance anomalies are discussed and some of the physical mechanisms that might be responsible for producing them are examined. It is argued that coronal abundances can provide important new diagnostics on physical processes at work in solar and stellar coronae. It seems likely that other hot astrophysical plasmas will be subject to similar effects.

  11. Element abundances in X-ray emitting plasmas in stars

    CERN Document Server

    Testa, Paola

    2010-01-01

    Studies of element abundances in stars are of fundamental interest for their impact in a wide astrophysical context, from our understanding of galactic chemistry and its evolution, to their effect on models of stellar interiors, to the influence of the composition of material in young stellar environments on the planet formation process. We review recent results of studies of abundance properties of X-ray emitting plasmas in stars, ranging from the corona of the Sun and other solar-like stars, to pre-main sequence low-mass stars, and to early-type stars. We discuss the status of our understanding of abundance patterns in stellar X-ray plasmas, and recent advances made possible by accurate diagnostics now accessible thanks to the high resolution X-ray spectroscopy with Chandra and XMM-Newton.

  12. Element Abundances and Source Plasma Temperatures of Solar Energetic Particles

    Science.gov (United States)

    Reames, Donald V.

    2016-11-01

    Thirty years ago Breneman and Stone [1] observed that the enhancement or suppression of element abundances in large solar energetic-particle (SEP) events varies as a power of the mass-to-charge ratio, A/Q, of the elements. Since Q during acceleration or transport may depend upon the source plasma temperature T, the pattern of element enhancements can provide a best-fit measure of T. The small SEP events we call 3He-rich or “impulsive” show average enhancements, relative to coronal abundances, rising as the 3.6 power of A/Q to a factor of ∼1000 for (76magnetic reconnection on open field lines in solar flares and jets. It has been recently found that the large shock-accelerated “gradual” SEP events have a broad range of source plasma temperatures; 69% have coronal temperatures of T seed population containing residual impulsive suprathermal ions. Most of the large event-to-event abundance variations and their time variation are largely explained by variations in T magnified by A/Q-dependent fractionation during transport. However, the non-thermal variance of impulsive SEP events (∼30%) exceeds that of the ∼3 MK gradual events (∼10%) so that several small impulsive events must be averaged together with the ambient plasma to form the seed population for shock acceleration in these events.

  13. Elemental abundances of flaring solar plasma - Enhanced neon and sulfur

    Science.gov (United States)

    Schmelz, J. T.

    1993-01-01

    Elemental abundances of two flares observed with the SMM Flat Crystal Spectrometer are compared and contrasted. The first had a gradual rise and a slow decay, while the second was much more impulsive. Simultaneous spectra of seven bright soft X-ray resonance lines provide information over a broad temperature range and are available throughout both flares, making these events unique in the SMM data base. For the first flare, the plasma seemed to be characterized by coronal abundances but, for the second, the plasma composition could not be coronal, photospheric, or a linear combination of both. A good differential emission measure fit required enhanced neon such that Ne/O = 0.32 +/- 0.02, a value which is inconsistent with the current models of coronal abundances based on the elemental first-ionization potential. Similar values of enhanced neon are found for flaring plasma observed by the SMM gamma-ray spectrometer, in (He-3)-rich solar energetic particle events, and in the decay phase of several long duration soft X-ray events. Sulfur is also enhanced in the impulsive flare, but not as dramatically as neon. These events are compared with two models which attempt to explain the enhanced values of neon and sulfur.

  14. Highly Multiplexed Profiling of Low Abundance Tumor Mutations in Plasma

    Science.gov (United States)

    Wiggin, Matthew; Pel, Joel; Vysotskaia, Valentina; Broemeling, David; Marziali, Andre; Hanson, Dan

    2013-01-01

    We have demonstrated a novel somatic mutation enrichment methodology demonstrating multiplexed detection of tumor mutations in plasma with sensitivity as low as 0.01% compared to normal DNA. This highly sensitive detection of low abundance mutations is achieved using electrophoretic separation and enrichment of DNA fragments containing point mutations over their wild-type counterparts. Commercialized as the OnTarget platform by Boreal Genomics, the system enriches nucleic acid samples for specific targets prior to amplification and detection, enabling the use of next-generation sequencing (NGS) or other detection assays for plasma or FFPE-based mutation detection and profiling. We present data demonstrating highly sensitive and multiplexed detection of panels of up to 100 mutations in plasma samples, improving the sensitivity of NGS assays to below 0.01% mutant content. We also report on concordance studies comparing low tumor content FFPE tissue and matched plasma in human samples demonstrating that OnTarget represents a robust, highly sensitive and multiplexed platform for non-invasive tumor monitoring.

  15. Element Abundances and Source Plasma Temperatures of Solar Energetic Particles

    CERN Document Server

    Reames, Donald V

    2016-01-01

    Thirty years ago Breneman and Stone observed that the enhancement or suppression of element abundances in large solar energetic-particle (SEP) events varies as a power of the mass-to-charge ratio, A/Q, of the elements. Since Q during acceleration or transport may depend upon the source plasma temperature T, the pattern of element enhancements can provide a best-fit measure of T. The small SEP events we call 3He-rich or "impulsive" show average enhancements, relative to coronal abundances, rising as the 3.6 power of A/Q to a factor of ~1000 for (76<=Z<=82)/O and temperature in the range 2-4 MK. This acceleration is believed to occur in islands of magnetic reconnection on open field lines in solar flares and jets. It has been recently found that the large shock-accelerated "gradual" SEP events have a broad range of source plasma temperatures; 69% have coronal temperatures of T < 1.6 MK, while 24% have T ~ 3 MK, the latter suggesting a seed population containing residual impulsive suprathermal ions. Mos...

  16. Depletion of abundant plasma proteins by poly(N-isopropylacrylamide-acrylic acid) hydrogel particles

    DEFF Research Database (Denmark)

    Such-Sanmartín, Gerard; Ventura-Espejo, Estela; Jensen, Ole N

    2014-01-01

    at higher efficiency than low abundance proteins, which are enriched in the supernatants, whereas (2) hydrogel particles incubated with high concentrations of plasma capture and irreversibly trap abundant proteins. During the elution step, irreversibly trapped proteins remain captured while low abundance...... (SRM) liquid chromatography (LC)-MS/MS. This novel use of hydrogel particles opens new perspectives for biomarker analysis based on mass spectrometry....

  17. An update on medium- and low-abundant blood plasma proteome of horse.

    Science.gov (United States)

    Lepczyński, A; Ożgo, M; Dratwa-Chałupnik, A; Robak, P; Pyć, A; Zaborski, D; Herosimczyk, A

    2017-07-10

    The main objectives of the study were to: (1) deeply analyse the serum protein composition of Equus caballus, (2) assess the effectiveness of the high-abundant protein depletion and improve the concentration of medium- and low-abundant proteins. The analysis were performed on the blood plasma of three healthy part-Arabian mares. The implementation of two-dimensional electrophoresis and matrix-assisted laser desorption/ionisation - time of flight mass spectrometry allowed us to establish a horse plasma proteome map. Serum proteins were resolved at pH 4 to 7, followed by 12% SDS-PAGE. As a result 136 spots were successfully identified, representing the products of 46 unique genes. Of these, 22 gene products have not been previously identified in horse serum/plasma samples using proteomic tools. Gene ontology analysis showed that almost 30% of all identified gene products belong to the coagulation and complement cascades. These results can undoubtedly serve as a useful and prospective prerequisite for the future analysis of horse plasma proteome changes in different physiological and pathophysiological conditions. The use of the medium- and low-abundant protein enrichment tool increased their abundance and allowed us to identify a higher number of protein gene products. The highest depletion efficiency was observed for the most abundant plasma proteins, that is albumin, IgG heavy chains and serotransferrin.

  18. The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances

    Science.gov (United States)

    Song, H. Q.; Chen, Y.; Li, B.; Li, L. P.; Zhao, L.; He, J. S.; Duan, D.; Cheng, X.; Zhang, J.

    2017-02-01

    Solar filaments/prominences are one of the most common features in the corona, which may lead to energetic coronal mass ejections (CMEs) and flares when they erupt. Filaments are about 100 times cooler and denser than the coronal material, and physical understanding of their material origin remains controversial. Two types of scenarios have been proposed: one argues that the filament plasma is brought into the corona from photosphere or chromosphere through a siphon or evaporation/injection process, while the other suggests that the material condenses from the surrounding coronal plasma due to thermal instability. The elemental abundance analysis is a reasonable clue to constrain the models, as the siphon or evaporation/injection model would predict that the filament material abundances are close to the photospheric or chromospheric ones, while the condensation model should have coronal abundances. In this Letter, we analyze the elemental abundances of a magnetic cloud that contains the ejected filament material. The corresponding filament eruption occurred on 1998 April 29, accompanying an M6.8 class soft X-ray flare located at the heliographic coordinates S18E20 (NOAA 08210) and a fast halo CME with the linear velocity of 1374 km s‑1 near the Sun. We find that the abundance ratios of elements with low and high first ionization potential such as Fe/O, Mg/O, and Si/O are 0.150, 0.050, and 0.070, respectively, approaching their corresponding photospheric values 0.065, 0.081, and 0.066, which does not support the coronal origin of the filament plasma.

  19. Analysis of the plasma proteome in COPD: Novel low abundance proteins reflect the severity of lung remodeling.

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    Merali, Salim; Barrero, Carlos A; Bowler, Russell P; Chen, Diane Er; Criner, Gerard; Braverman, Alan; Litwin, Samuel; Yeung, Anthony; Kelsen, Steven G

    2014-04-01

    The search for COPD biomarkers has largely employed a targeted approach that focuses on plasma proteins involved in the systemic inflammatory response and in lung injury and repair. This proof of concept study was designed to test the idea that an open, unbiased, in-depth proteomics approach could identify novel, low abundance plasma proteins i.e., ng/mL concentration, which could serve as potential biomarkers. Differentially expressed proteins were identified in a discovery group with severe COPD (FEV1 <45% predicted; n = 10). Subjects with normal lung function matched for age, sex, ethnicity and smoking history served as controls (n = 10). Pooled plasma from each group was exhaustively immunodepleted of abundant proteins, d separated by 1-D gel electrophoresis and extensively fractionated prior to LC-tandem mass spectroscopy (GeLC-MS). Thirty one differentially expressed proteins were identified in the discovery group including markers of lung defense against oxidant stress, alveolar macrophage activation, and lung tissue injury and repair. Four of the 31 proteins (i.e., GRP78, soluble CD163, IL1AP and MSPT9) were measured in a separate verification group of 80 subjects with varying COPD severity by immunoassay. All 4 were significantly altered in COPD and 2 (GRP78 and soluble CD163) correlated with both FEV1 and the extent of emphysema. In-depth, plasma proteomic analysis identified a group of novel, differentially expressed, low abundance proteins that reflect known pathogenic mechanisms and the severity of lung remodeling in COPD. These proteins may also prove useful as COPD biomarkers.

  20. What are the Sources of Solar Energetic Particles? Element Abundances and Source Plasma Temperatures

    CERN Document Server

    Reames, Donald V

    2015-01-01

    We have spent 50 years in heated discussion over which populations of solar energetic particles (SEPs) are accelerated at flares and which by shock waves driven out from the Sun by coronal mass ejections (CMEs). The association of the large "gradual" SEP events with shock acceleration is supported by the extensive spatial distribution of SEPs and by the delayed acceleration of the particles. The relative abundances of the elements in these gradual events are a measure of those in the ambient solar corona, differing from those in the photosphere by a widely-observed function of the first ionization potential (FIP) of the elements. SEP events we call "impulsive", the traditional "3He-rich" events with enhanced heavy-element abundances, are associated with type III radio bursts, flares, and narrow CMEs; they selectively populate flux tubes that thread a localized source, and they are fit to new particle-in-cell models of magnetic reconnection on open field lines as found in solar jets. These models help explain ...

  1. Detection and quantitation of twenty-seven cytokines, chemokines and growth factors pre- and post-high abundance protein depletion in human plasma

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    Seong-Beom Ahn

    2014-06-01

    Full Text Available Cytokines, chemokines and growth factors (CCGFs in human plasma are analyzed for identification of biomarkers. However concentrations of CCGFs are very low; it is difficult to identify and quantify low abundance proteins in the presence of the high abundance proteins (HAPs unless HAPs are removed prior to analysis. However, there is a concern that the low abundance proteins such as CCGFs may also be removed during the HAP depletion process. In this study, we have examined whether or not depletion of the HAPs enhances detection of the CCGFs by immuno-assays. Top 14 HAPs were depleted from 10 healthy volunteers’ plasma using MARS-14 immuno-depletion column and a total of 27 CCGFs were analyzed by bead-based multiplexed immuno-assay. All 27 CCGFs were detected in neat plasma (NP, 25 were detected in flow through fraction (FT and 21 were detected in bound protein (BP fraction. Concentrations of 22 CCGFs were significantly higher in NP compared to FT and BP. Only one CCGF had higher concentration in FT compared to NP. The remaining 2 CCGFs were not different between NP and FT. It was counter-productive for the detection of 24 CCGFs after HAP removal, primarily due to post-depletion protein precipitation and/or re-suspension of pellets.

  2. Natural carbon isotope abundance of plasma metabolites and liver tissue differs between diabetic and non-diabetic Zucker diabetic fatty rats.

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    Jean-Philippe Godin

    Full Text Available BACKGROUND: 'You are what you eat' is an accurate summary for humans and animals when it comes to carbon isotope abundance. In biological material, natural(13C/(12C ratio is subject to minute variations due to diet composition (mainly from ingestion of C3 and C4 metabolism plants and to the discrimination between 'light' and 'heavy' isotopes during biochemical reactions (isotope effects and isotopic fractionation. METHODOLOGY/PRINCIPAL FINDINGS: Carbon isotopic abundance was measured in ZDF (fa/+ and ZDF (fa/fa, (lean and obese-diabetic rats respectively fed the same diet. By analysing plasma metabolites (glucose and non-esterified fatty acids, breath and liver tissue by high-precision isotope ratio mass spectrometry, we demonstrate for the first time statistically distinguishable metabolic carbon isotope abundance between ZDF (fa/+ and ZDF (fa/fa rats based on plasma glucose, palmitic, oleic, linoleic, arachidonic acids and bulk analysis of liver tissue (P<0.005 resulting into clear isotopic fingerprints using principal component analysis. We studied the variation of isotopic abundance between both groups for each metabolite and through the metabolic pathways using the precursor/product approach. We confirmed that lipids were depleted in (13C compared to glucose in both genotypes. We found that isotopic abundance of linoleic acid (C18: 2n-6, even though both groups had the same feed, differed significantly between both groups. The likely reason for these changes between ZDF (fa/+ and ZDF (fa/fa are metabolic dysregulation associated with various routing and fluxes of metabolites. CONCLUSION/SIGNIFICANCE: This work provides evidence that measurement of natural abundance isotope ratio of both bulk tissue and individual metabolites can provide meaningful information about metabolic changes either associated to phenotype or to genetic effects; irrespective of concentration. In the future measuring the natural abundance δ(13C of key metabolites

  3. Rapid Upregulation of Orai1 Abundance in the Plasma Membrane of Platelets Following Activation with Thrombin and Collagen Related Peptide

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    Guilai Liu

    2015-11-01

    Full Text Available Background: Blood platelets accomplish primary hemostasis following vascular injury and contribute to the orchestration of occlusive vascular disease. Platelets are activated by an increase of cytosolic Ca2+-activity ([Ca2+]i, which is accomplished by Ca2+-release from intracellular stores and subsequent store operated Ca2+ entry (SOCE through Ca2+ release activated Ca2+ channel moiety Orai1. Powerful activators of platelets include thrombin and collagen related peptide (CRP, which are in part effective by activation of small G- protein Rac1. The present study explored the influence of thrombin and CRP on Orai1 protein abundance and cytosolic Ca2+-activity ([Ca2+]i in platelets drawn from wild type mice. Methods: Orai1 protein surface abundance was quantified utilizing CF™488A conjugated antibodies, and [Ca2+]i was determined with Fluo3-fluorescence. Results: In resting platelets, Orai1 protein abundance and [Ca2+]i were low. Thrombin (0.02 U/ml and CRP (5ug/ml within 2 min increased [Ca2+]i and Orai1 protein abundance at the platelet surface. [Ca2+]i was further increased by Ca2+ ionophore ionomycin (1 µM and by store depletion with the sarcoendoplasmatic Ca2+ ATPase inhibitor thapsigargin (1 µM. However, Orai1 protein abundance at the platelet surface was not significantly affected by ionomycin and only slightly increased by thapsigargin. The effect of thrombin and CRP on Orai1 abundance and [Ca2+]i was significantly blunted by Rac1 inhibitor NSC23766 (50 µM. Conclusion: The increase of [Ca2+]i following stimulation of platelets with thrombin and collagen related peptide is potentiated by ultrarapid Rac1 sensitive translocation of Orai1 into the cell membrane.

  4. Standard test method for isotopic abundance analysis of uranium hexafluoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2014-01-01

    1.1 This test method covers the isotopic abundance analysis of 234U, 235U, 236U and 238U in samples of hydrolysed uranium hexafluoride (UF6) by inductively coupled plasma source, multicollector, mass spectrometry (ICP-MC-MS). The method applies to material with 235U abundance in the range of 0.2 to 6 % mass. This test method is also described in ASTM STP 1344. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  5. Introduction of enteral food increases plasma GLP-2 and decreases GLP-2 receptor mRNA abundance during pig development

    DEFF Research Database (Denmark)

    Petersen, Yvette M; Hartmann, Bolette; Holst, Jens Juul

    2003-01-01

    transcription polymerase chain reaction) during pre- and postnatal development and the relationship between these variables and small intestinal growth in enterally and parenterally fed fetal and newborn pigs (premature and term-delivered, 92 and 100% gestation, respectively). Plasma GLP-2 concentrations...... of colostrum in fetal pigs at 92% gestation compared with untreated controls (59 +/- 11 vs. 7 +/- 2 pmol/L, P parenteral infusion of elemental nutrients, but the time course...... in these pigs. We conclude that the introduction of enteral feeding transiently increases plasma GLP-2 concentrations and decreases small intestinal GLP-2R mRNA levels during pig development. GLP-2 may play a role in the growth of the small intestine around birth and weaning via a response to enteral nutrition....

  6. Determinations of rare earth element abundance and U-Pb age of zircons using multispot laser ablation-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Yokoyama, Takaomi D; Suzuki, Toshihiro; Kon, Yoshiaki; Hirata, Takafumi

    2011-12-01

    We have developed a new calibration technique for multielement determination and U-Pb dating of zircon samples using laser ablation-inductively coupled plasma mass spectrometry (ICPMS) coupled with galvanometric optics. With the galvanometric optics, laser ablation of two or more sample materials could be achieved in very short time intervals (~10 ms). The resulting sample aerosols released from different ablation pits or different solid samples were mixed and homogenized within the sample cell and then transported into the ICP ion source. Multiple spot laser ablation enables spiking of analytes or internal standard elements directly into the solid samples, and therefore the standard addition calibration method can be applied for the determination of trace elements in solid samples. In this study, we have measured the rare earth element (REE) abundances of two zircon samples (Nancy 91500 and Prešovice) based on the standard addition technique, using a direct spiking of analytes through a multispot laser ablation of the glass standard material (NIST SRM612). The resulting REE abundance data show good agreement with previously reported values within analytical uncertainties achieved in this study (10% for most elements). Our experiments demonstrated that nonspectroscopic interferences on 14 REEs could be significantly reduced by the standard addition technique employed here. Another advantage of galvanometric devices is the accumulation of sample aerosol released from multiple spots. In this study we have measured the U-Pb age of a zircon sample (LMR) using an accumulation of sample aerosols released from 10 separate ablation pits of low diameters (~8 μm). The resulting (238)U-(206)Pb age data for the LMR zircons was 369 ± 64 Ma, which is in good agreement with previously reported age data (367.6 ± 1.5 Ma). (1) The data obtained here clearly demonstrate that the multiple spot laser ablation-ICPMS technique can become a powerful approach for elemental and isotopic

  7. Extensive determination of glycan heterogeneity reveals an unusual abundance of high mannose glycans in enriched plasma membranes of human embryonic stem cells.

    Science.gov (United States)

    An, Hyun Joo; Gip, Phung; Kim, Jaehan; Wu, Shuai; Park, Kun Wook; McVaugh, Cheryl T; Schaffer, David V; Bertozzi, Carolyn R; Lebrilla, Carlito B

    2012-04-01

    Most cell membrane proteins are known or predicted to be glycosylated in eukaryotic organisms, where surface glycans are essential in many biological processes including cell development and differentiation. Nonetheless, the glycosylation on cell membranes remains not well characterized because of the lack of sensitive analytical methods. This study introduces a technique for the rapid profiling and quantitation of N- and O-glycans on cell membranes using membrane enrichment and nanoflow liquid chromatography/mass spectrometry of native structures. Using this new method, the glycome analysis of cell membranes isolated from human embryonic stem cells and somatic cell lines was performed. Human embryonic stem cells were found to have high levels of high mannose glycans, which contrasts with IMR-90 fibroblasts and a human normal breast cell line, where complex glycans are by far the most abundant and high mannose glycans are minor components. O-Glycosylation affects relatively minor components of cell surfaces. To verify the quantitation and localization of glycans on the human embryonic stem cell membranes, flow cytometry and immunocytochemistry were performed. Proteomics analyses were also performed and confirmed enrichment of plasma membrane proteins with some contamination from endoplasmic reticulum and other membranes. These findings suggest that high mannose glycans are the major component of cell surface glycosylation with even terminal glucoses. High mannose glycans are not commonly presented on the surfaces of mammalian cells or in serum yet may play important roles in stem cell biology. The results also mean that distinguishing stem cells from other mammalian cells may be facilitated by the major difference in the glycosylation of the cell membrane. The deep structural analysis enabled by this new method will enable future mechanistic studies on the biological significance of high mannose glycans on stem cell membranes and provide a general tool to examine

  8. Influence of relative abundance of isotopes on depth resolution for depth profiling of metal coatings by laser ablation inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Fariñas, Juan C; Coedo, Aurora G; Dorado, Teresa

    2010-04-15

    A systematic study on the influence of relative abundance of isotopes of elements in the coating (A(c)) and in the substrate (A(s)) on both shape of time-resolved signals and depth resolution (Delta z) was performed for depth profile analysis of metal coatings on metal substrates by ultraviolet (266 nm) nanosecond laser ablation inductively coupled plasma quadrupole mass spectrometry. Five coated samples with coating thicknesses of the same order of magnitude (20-30 microm) were tested: nickel coating on aluminium, chromium and copper, and steel coated with copper and zinc. A laser repetition rate of 1 Hz and a laser fluence of 21 J cm(-2) were used. Five different depth profile types were established, which showed a clear dependence on A(c)/A(s) ratio. In general, depth profiles obtained for ratios above 1-10 could not be used to determine Delta z. We found that Delta z increased non-linearly with A(c)/A(s) ratio. The best depth profile types, leading to highest depth resolution and reproducibility, were attained in all cases by using the isotopes with low/medium A(c) values and with the highest A(s) values. In these conditions, an improvement of up to 4 times in Delta z values was achieved. The average ablation rates were in the range from 0.55 microm pulse(-1) for copper coating on steel to 0.83 microm pulse(-1) for zinc coating on steel, and the Delta z values were between 2.74 microm for nickel coating on chromium and 5.91 microm for nickel coating on copper, with RSD values about 5-8%.

  9. A deep survey of heavy element lines in planetary nebulae -- II. Recombination line abundances and evidence for ultra-cold plasma

    CERN Document Server

    Tsamis, Y G; Liu, X W; Storey, P J; Danziger, I J

    2004-01-01

    [Abridged] Deep optical observations of the spectra of 12 Galactic planetary nebulae (PNe) and 3 Magellanic Cloud PNe were presented in Paper I by Tsamis et al. (2003b), who carried out an abundance analysis using the collisionally excited forbidden lines. Here, the relative intensities of faint optical recombination lines (ORLs) from ions of carbon, nitrogen and oxygen are analysed in order to derive the abundances of these ions relative to hydrogen. We define an abundance discrepancy factor (ADF) as the ratio of the abundance derived for a heavy element ion from its recombination lines to that derived for the same ion from its ultraviolet, optical or infrared collisionally excited lines (CELs). All of the PNe in our sample are found to have ADF's that exceed unity. There is no dependence of the magnitude of the ADF upon the excitation energy of the UV, optical or IR CEL transition used, indicating that classical nebular temperature fluctuations--i.e. in a chemically homogeneous medium--are not the cause of ...

  10. Oolemmal proteomics – identification of highly abundant heat shock proteins and molecular chaperones in the mature mouse egg and their localization on the plasma membrane

    Science.gov (United States)

    Calvert, Meredith E; Digilio, Laura C; Herr, John C; Coonrod, Scott A

    2003-01-01

    Background The mature mouse egg contains the full complement of maternal proteins required for fertilization, the transition to zygotic transcription, and the beginning stages of embryogenesis. Many of these proteins remain to be characterized, therefore in this study we have identified highly abundant egg proteins using a proteomic approach and found that several of these proteins also appear to localize to the egg surface. Characterization of such molecules will provide important insight into the cellular events of fertilization and early development. Methods In order to identify some of the more abundant egg proteins, whole egg extracts were resolved on coomassie-stained two-dimensional (2D) PAGE gels. Several highly abundant protein spots were cored and microsequenced by tandem mass spectrometry (TMS), and determined to be molecular chaperone proteins. Concurrent experiments were performed to identify oolemmal proteins using 2D avidin blotting. Proteins spots that appeared to be surface labeled by biotinylation were correlated with the initial coomassie-stained reference gel. Surprisingly, some of the surface labelled proteins corresponded to those abundant chaperone proteins previously identified. To confirm whether these molecules are accumulating at the oolemmal surface in eggs, we performed immunofluoresence on live, zona-free eggs using antibodies to HSP70, HSP90, GRP94, GRP78, calreticulin and calnexin. Results The putative surface-labeled proteins identified by biotinylation included the molecular chaperones HSP70 (MW 70 KDa, pI 5.5), HSP90a (MW 85 KDa, pI 4.9), GRP94 (MW 92 KDa, pI 4.7), GRP78 (MW 72 KDa, pI 5.0), Oxygen regulated protein 150 (ORP150; MW 111 KDa, pI 5.1), Calreticulin (MW 48 KDa, pI 4.3), Calnexin (MW 65 KDa, pI 4.5), and Protein disulfide isomerase (PDI; MW 57 KDa, pI 4.8). Immunofluoresence results showed that antibodies to HSP90, GRP94, GRP78 and calreticulin were reactive with oolemmal proteins. We were unable to confirm surface

  11. Oolemmal proteomics – identification of highly abundant heat shock proteins and molecular chaperones in the mature mouse egg and their localization on the plasma membrane

    Directory of Open Access Journals (Sweden)

    Herr John C

    2003-02-01

    Full Text Available Abstract Background The mature mouse egg contains the full complement of maternal proteins required for fertilization, the transition to zygotic transcription, and the beginning stages of embryogenesis. Many of these proteins remain to be characterized, therefore in this study we have identified highly abundant egg proteins using a proteomic approach and found that several of these proteins also appear to localize to the egg surface. Characterization of such molecules will provide important insight into the cellular events of fertilization and early development. Methods In order to identify some of the more abundant egg proteins, whole egg extracts were resolved on coomassie-stained two-dimensional (2D PAGE gels. Several highly abundant protein spots were cored and microsequenced by tandem mass spectrometry (TMS, and determined to be molecular chaperone proteins. Concurrent experiments were performed to identify oolemmal proteins using 2D avidin blotting. Proteins spots that appeared to be surface labeled by biotinylation were correlated with the initial coomassie-stained reference gel. Surprisingly, some of the surface labelled proteins corresponded to those abundant chaperone proteins previously identified. To confirm whether these molecules are accumulating at the oolemmal surface in eggs, we performed immunofluoresence on live, zona-free eggs using antibodies to HSP70, HSP90, GRP94, GRP78, calreticulin and calnexin. Results The putative surface-labeled proteins identified by biotinylation included the molecular chaperones HSP70 (MW 70 KDa, pI 5.5, HSP90a (MW 85 KDa, pI 4.9, GRP94 (MW 92 KDa, pI 4.7, GRP78 (MW 72 KDa, pI 5.0, Oxygen regulated protein 150 (ORP150; MW 111 KDa, pI 5.1, Calreticulin (MW 48 KDa, pI 4.3, Calnexin (MW 65 KDa, pI 4.5, and Protein disulfide isomerase (PDI; MW 57 KDa, pI 4.8. Immunofluoresence results showed that antibodies to HSP90, GRP94, GRP78 and calreticulin were reactive with oolemmal proteins. We were unable to

  12. Oolemmal proteomics--identification of highly abundant heat shock proteins and molecular chaperones in the mature mouse egg and their localization on the plasma membrane.

    Science.gov (United States)

    Calvert, Meredith E; Digilio, Laura C; Herr, John C; Coonrod, Scott A

    2003-02-14

    The mature mouse egg contains the full complement of maternal proteins required for fertilization, the transition to zygotic transcription, and the beginning stages of embryogenesis. Many of these proteins remain to be characterized, therefore in this study we have identified highly abundant egg proteins using a proteomic approach and found that several of these proteins also appear to localize to the egg surface. Characterization of such molecules will provide important insight into the cellular events of fertilization and early development. In order to identify some of the more abundant egg proteins, whole egg extracts were resolved on coomassie-stained two-dimensional (2D) PAGE gels. Several highly abundant protein spots were cored and microsequenced by tandem mass spectrometry (TMS), and determined to be molecular chaperone proteins. Concurrent experiments were performed to identify oolemmal proteins using 2D avidin blotting. Proteins spots that appeared to be surface labeled by biotinylation were correlated with the initial coomassie-stained reference gel. Surprisingly, some of the surface labelled proteins corresponded to those abundant chaperone proteins previously identified. To confirm whether these molecules are accumulating at the oolemmal surface in eggs, we performed immunofluoresence on live, zona-free eggs using antibodies to HSP70, HSP90, GRP94, GRP78, calreticulin and calnexin. The putative surface-labeled proteins identified by biotinylation included the molecular chaperones HSP70 (MW 70 KDa, pI 5.5), HSP90a (MW 85 KDa, pI 4.9), GRP94 (MW 92 KDa, pI 4.7), GRP78 (MW 72 KDa, pI 5.0), Oxygen regulated protein 150 (ORP150; MW 111 KDa, pI 5.1), Calreticulin (MW 48 KDa, pI 4.3), Calnexin (MW 65 KDa, pI 4.5), and Protein disulfide isomerase (PDI; MW 57 KDa, pI 4.8). Immunofluoresence results showed that antibodies to HSP90, GRP94, GRP78 and calreticulin were reactive with oolemmal proteins. We were unable to confirm surface localization of HSP70 or

  13. Alpha-tocotrienol is the most abundant tocotrienol isomer circulated in plasma and lipoproteins after postprandial tocotrienol-rich vitamin E supplementation

    Directory of Open Access Journals (Sweden)

    Fairus Syed

    2012-01-01

    Full Text Available Abstract Background Tocotrienols (T3 and tocopherols (T, both members of the natural vitamin E family have unique biological functions in humans. T3 are detected in circulating human plasma and lipoproteins, although at concentrations significantly lower than α-tocopherol (α-T. T3, especially α-T3 is known to be neuropotective at nanomolar concentrations and this study evaluated the postprandial fate of T3 and α-T in plasma and lipoproteins. Methods Ten healthy volunteers (5 males and 5 females were administered a single dose of vitamin E [526 mg palm tocotrienol-rich fraction (TRF or 537 mg α-T] after 7-d pre-conditioning on a T3-free diet. Blood was sampled at baseline (fasted and 2, 4, 5, 6, 8, and 24 h after supplementation. Concentrations of T and T3 isomers in plasma, triacylglycerol-rich particles (TRP, LDL, and HDL were measured at each postprandial interval. Results After TRF supplementation, plasma α-T3 and γ-T3 peaked at 5 h (α-T3: 4.74 ± 1.69 μM; γ-T3: 2.73 ± 1.27 μM. δ-T3 peaked earlier at 4 h (0.53 ± 0.25 μM. In contrast, α-T peaked at 6 h (30.13 ± 2.91 μM and 8 h (37.80 ± 3.59 μM following supplementation with TRF and α-T, respectively. α-T was the major vitamin E isomer detected in plasma, TRP, LDL, and HDL even after supplementation with TRF (composed of 70% T3. No T3 were detected during fasted states. T3 are detected postprandially only after TRF supplementation and concentrations were significantly lower than α-T. Conclusions Bio-discrimination between vitamin E isomers in humans reduces the rate of T3 absorption and affects their incorporation into lipoproteins. Although low absorption of T3 into circulation may impact some of their physiological functions in humans, T3 have biological functions well below concentration noted in this study.

  14. High-Resolution X-ray Spectroscopy of Hercules X-1 with the XMM-Newton RGS CNO Element Abundance Measurements and Density Diagnostics of a Photoionized Plasma

    CERN Document Server

    Jiménez-Garate, M A; Den Herder, J W A; Zane, S; Ramsay, G

    2002-01-01

    We analyze the high-resolution X-ray spectrum of Hercules X-1, an intermediate-mass X-ray binary, which was observed with the XMM-Newton Reflection Grating Spectrometer. We measure the elemental abundance ratios by use of spectral models, and we detect material processed through the CNO-cycle. The CNO abundances, and in particular the ratio N/O > 4.0 times solar, provide stringent constraints on the evolution of the binary system. The low and short-on flux states of Her X-1 exhibit narrow line emission from C VI, N VI, N VII, O VII, O VIII, Ne IX, and Ne X ions. The spectra show signatures of photoionization. We measure the electron temperature, quantify photoexcitation in the He alpha lines, and set limits on the location and density of the gas. The recombination lines may originate in the accretion disk atmosphere and corona, or on the X-ray illuminated face of the mass donor (HZ Her). The spectral variation over the course of the 35 d period provides additional evidence for the precession of the disk. Duri...

  15. NKCC1 and NHE1 are abundantly expressed in the basolateral plasma membrane of secretory coil cells in rat, mouse, and human sweat glands

    DEFF Research Database (Denmark)

    Nejsum, Lene Niemann; Prætorius, Jeppe; Nielsen, Søren

    2005-01-01

    1 (NHE1) protein has been localized to both the duct and secretory coil of human sweat duct; however, the NHE1 abundance in the duct was not compared with that in the secretory coil. The aim of this study was to test whether mRNA encoding NKCC1, NKCC2, and Na(+)-coupled acid-base transporters...... and the corresponding proteins are expressed in rodent sweat glands and, if expressed, to determine the cellular and subcellular localization in rat, mouse, and human eccrine sweat glands. NKCC1 mRNA was demonstrated in rat palmar tissue, including sweat glands, using RT-PCR, whereas NKCC2 mRNA was absent. Also, NHE1 m...... palmar skin by immunoblotting, whereas NKCC2, NHE2, and NHE3 proteins were not detected. Immunohistochemistry was performed using sections from rat, mouse, and human palmar tissue. Immunoperoxidase labeling revealed abundant expression of NKCC1 and NHE1 in the basolateral domain of secretory coils of rat...

  16. NKCC1 and NHE1 are abundantly expressed in the basolateral plasma membrane of secretory coil cells in rat, mouse, and human sweat glands

    DEFF Research Database (Denmark)

    Nejsum, Lene Niemann; Prætorius, Jeppe; Nielsen, Søren

    2005-01-01

    In isolated sweat glands, bumetanide inhibits sweat secretion. The mRNA encoding bumetanide-sensitive Na(+)-K(+)-Cl(-) cotransporter (NKCC) isoform 1 (NKCC1) has been detected in sweat glands; however, the cellular and subcellular protein localization is unknown. Na(+)/H(+) exchanger (NHE) isoform...... 1 (NHE1) protein has been localized to both the duct and secretory coil of human sweat duct; however, the NHE1 abundance in the duct was not compared with that in the secretory coil. The aim of this study was to test whether mRNA encoding NKCC1, NKCC2, and Na(+)-coupled acid-base transporters...... and the corresponding proteins are expressed in rodent sweat glands and, if expressed, to determine the cellular and subcellular localization in rat, mouse, and human eccrine sweat glands. NKCC1 mRNA was demonstrated in rat palmar tissue, including sweat glands, using RT-PCR, whereas NKCC2 mRNA was absent. Also, NHE1 m...

  17. Nitrate transport in cucumber leaves is an inducible process involving an increase in plasma membrane H+-ATPase activity and abundance

    Directory of Open Access Journals (Sweden)

    Nikolic Miroslav

    2012-05-01

    Full Text Available Abstract Background The mechanisms by which nitrate is transported into the roots have been characterized both at physiological and molecular levels. It has been demonstrated that nitrate is taken up in an energy-dependent way by a four-component uptake machinery involving high- and low- affinity transport systems. In contrast very little is known about the physiology of nitrate transport towards different plant tissues and in particular at the leaf level. Results The mechanism of nitrate uptake in leaves of cucumber (Cucumis sativus L. cv. Chinese long plants was studied and compared with that of the root. Net nitrate uptake by roots of nitrate-depleted cucumber plants proved to be substrate-inducible and biphasic showing a saturable kinetics with a clear linear non saturable component at an anion concentration higher than 2 mM. Nitrate uptake by leaf discs of cucumber plants showed some similarities with that operating in the roots (e.g. electrogenic H+ dependence via involvement of proton pump, a certain degree of induction. However, it did not exhibit typical biphasic kinetics and was characterized by a higher Km with values out of the range usually recorded in roots of several different plant species. The quantity and activity of plasma membrane (PM H+-ATPase of the vesicles isolated from leaf tissues of nitrate-treated plants for 12 h (peak of nitrate foliar uptake rate increased with respect to that observed in the vesicles isolated from N-deprived control plants, thus suggesting an involvement of this enzyme in the leaf nitrate uptake process similar to that described in roots. Molecular analyses suggest the involvement of a specific isoform of PM H+-ATPase (CsHA1 and NRT2 transporter (CsNRT2 in root nitrate uptake. At the leaf level, nitrate treatment modulated the expression of CsHA2, highlighting a main putative role of this isogene in the process. Conclusions Obtained results provide for the first time evidence that a saturable

  18. Pancreatic cancer with a high serum IgG4 concentration

    Institute of Scientific and Technical Information of China (English)

    Terumi Kamisawa; Pong Yui Chen; Yuyang Tu; Hitoshi Nakajima; Naoto Egawa; Kouji Tsuruta; Atsutake Okamoto; Tsunekazu Hishima

    2006-01-01

    Differentiation between autoimmune pancreatitis and pancreatic cancer is sometimes difficult. It has been reported that serum IgG4 concentrations are significantly elevated and particularly high (>135 mg/dL) in autoimmune pancreatitis. Measurement of serum IgG4 has become a useful tool for differentiating between autoimmune pancreatitis and pancreatic cancer. However,we present a 74-year-old female with a markedly elevated serum IgG4 (433 mg/dL) who underwentpancreaticoduodenectomy for pancreatic cancer. Elevated serum IgG4 levels continued after the resection. On histology, adenocarcinoma of the pancreas accompanied with moderate lymphoplasmacytic infiltration infiltrated the lower bile duct and duodenum, but there were no findings of autoimmune pancreatitis. Although a small metastasis was detected in one parapancreatic lymph node, regional lymph nodes were swollen. Abundant IgG4-positive plasma cells infiltrated the cancerous areas of the pancreas, but only a few IgG4-positive plasma cells were detected in the noncancerous areas.Pancreatic cancer cells were not immunoreactive for IgG4. An abundant infiltration of IgG4-positive plasma cells was detected in the swollen regional lymph nodes and in the duodenal mucosa. We believe that the serum IgG4 level was elevated in this patient with pancreatic cancer as the result of an IgG4-related systemic disease that had no clinical manifestations other than lymphadenopathy.

  19. 生长素调控极性运输载体PIN2质膜丰度与降解%Auxin regulation of its efflux transporter PIN2 plasma membrane abundance and degradation

    Institute of Scientific and Technical Information of China (English)

    付伟; 严旭; 王超; 潘建伟

    2013-01-01

    The effects of long-term (8 h) treatments with exogenous auxins on auxin efflux transporter PIN2-GFP plasma membrane (PM) abundance,and low temperature,KCN and auxin receptors TIR1/AFBs mutation on auxin regulation of PIN2-GFP PM abundance,and ConA,a vacuolar H +-ATPase inhibitor,on vacuolar accumulation of PIN2-GFP in wild-type and auxin receptor quadruple mutants tir1afb1,2,3 cells in Arabidopsis were systematically studied.The results revealed that exogenous auxins down-regulated PIN2-GFP PM abundance through TIR1/AFB-mediated signaling and promoted PIN2-GFP internalization,intracellular membrane trafficking,and vacuolar degradation,indicating that auxin feedback regulates PIN2-GFP PM levels through TIR1/AFB-mediated signaling and inhibits excessive transport of intracellular auxin out of the cell.%主要观察了外源生长素长时间(8 h)处理对拟南芥生长素极性输出载体PIN2-GFP质膜丰度的影响,低温、KCN处理和生长素受体突变对生长素调控质膜PIN2-GFP丰度的影响,以及液泡H+-ATPase抑制剂ConA对野生型和生长素受体四突变体tir1aafb1,2,3液泡中PIN2-GFP积累的影响.结果表明:外源生长素通过其受体TIR1/AFB介导的信号途径下调质膜PIN2-GFP的丰度,促进PIN2-GFP的内吞、胞内运输和液泡降解.暗示生长素通过TIR1/AFB介导的信号途径反馈调控质膜PIN2-GFP的水平,从而阻止了胞内生长素的过多输出.

  20. Real-time RT-PCR quantification of pregnancy-associated plasma protein-A mRNA abundance in bovine granulosa and theca cells: effects of hormones in vitro.

    Science.gov (United States)

    Aad, Pauline Y; Voge, Justin L; Santiago, Consuelo A; Malayer, Jerry R; Spicer, Leon J

    2006-11-01

    Ovarian follicular growth and dominance are controlled by a series of hormonal and intraovarian events including a decrease in intrafollicular IGF-binding proteins -2, -4 and -5 levels. Proteolytic enzymes such as pregnancy-associated plasma protein-A (PAPP-A) degrade IGFBPs and increase bioavailability of IGF-I and -II during follicular development. The objective of this study was to determine the effect of IGF-I, IGF-II, insulin (INS), LH, FSH, estradiol (E2), leptin or cortisol on ovarian PAPP-A mRNA levels. Granulosa (GC) from small (SM) (1-5 mm) and large (LG) (8-22 mm) follicles as well as theca cells (TC) from LG follicles were collected from bovine ovaries and cultured for 48 h in medium containing 10% FCS and then treated with various hormones in serum-free medium for an additional 24 h. Cells were treated with various concentrations (3-500 ng/ml) and combinations of IGF-I, IGF-II, FSH, LH, E2, INS, leptin and (or) cortisol for 24 h (Experiments 1-10). PAPP-A mRNA levels were measured using quantitative real-time RT-PCR. In SM-GC and LG-GC, none of the treatments significantly affected (P>0.10) PAPP-A mRNA abundance. In LG-TC, IGF-I, LH or cortisol did not affect (P>0.10) PAPP-A mRNA levels, whereas INS with or without LH decreased (P<0.05) PAPP-A mRNA. E2 alone decreased PAPP-A mRNA levels in LG-TC, and E2 amplified the insulin-induced inhibition of PAPP-A mRNA abundance in LG-TC. We conclude that control of PAPP-A mRNA abundance in granulosa and theca cells differs, and that E2 may be part of an intraovarian negative feedback system which may reduce the bioavailable IGFs in the theca layer during growth and selection of follicles.

  1. Effect of long-term fasting and a subsequent meal on mRNA abundances of hypothalamic appetite regulators, central and peripheral leptin expression and plasma leptin levels in rainbow trout.

    Science.gov (United States)

    Jørgensen, Even H; Bernier, Nicholas J; Maule, Alec G; Vijayan, Mathilakath M

    2016-12-01

    Knowledge about neuroendocrine mechanisms regulating appetite in fish, including the role of leptin, is inconclusive. We investigated leptin mRNA abundance in various tissues, plasma leptin levels and the hypothalamic gene expression of putative orexigenic (neuropeptide Y and agouti-regulated peptide) and anorexigenic (melanocortin receptor, proopiomelanocortins (POMCs), cocaine- and amphetamine-regulated transcript and corticotropin-releasing factor) neuropeptides in relation to feeding status in rainbow trout (Oncorhynchus mykiss). Blood and tissues were first (Day 1) sampled from trout that had been fed or fasted for 4 months and the day after (Day 2) from fasted fish after they had been given a large meal, and their continuously fed counterparts. The fasted fish ate vigorously when they were presented a meal. There were no differences between fed, fasted and re-fed fish in hypothalamic neuropeptide transcript levels, except for pomca1 and pomcb, which were higher in fasted fish than in fed fish at Day 1, and which, for pomcb, decreased to the level in fed fish after the meal at Day 2. Plasma leptin levels did not differ between fasted, re-fed and fed fish. A higher leptina1 transcript level was seen in the belly flap of fasted fish than in fed fish, even after re-feeding on Day 2. The data do not reveal causative roles of the investigated brain neuropeptides, or leptin, in appetite regulation. It is suggested that the elevated pomc transcript levels provide a satiety signal that reduces energy expenditure during prolonged fasting. The increase in belly flap leptin transcript with fasting, which did not decrease upon re-feeding, indicates a tissue-specific role of leptin in long-term regulation of energy homeostasis. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Development of a Chip/Chip/SRM platform using digital chip isoelectric focusing and LC-Chip mass spectrometry for enrichment and quantitation of low abundance protein biomarkers in human plasma.

    Science.gov (United States)

    Rafalko, Agnes; Dai, Shujia; Hancock, William S; Karger, Barry L; Hincapie, Marina

    2012-02-03

    Protein biomarkers are critical for diagnosis, prognosis, and treatment of disease. The transition from protein biomarker discovery to verification can be a rate limiting step in clinical development of new diagnostics. Liquid chromatography-selected reaction monitoring mass spectrometry (LC-SRM MS) is becoming an important tool for biomarker verification studies in highly complex biological samples. Analyte enrichment or sample fractionation is often necessary to reduce sample complexity and improve sensitivity of SRM for quantitation of clinically relevant biomarker candidates present at the low ng/mL range in blood. In this paper, we describe an alternative method for sample preparation for LC-SRM MS, which does not rely on availability of antibodies. This new platform is based on selective enrichment of proteotypic peptides from complex biological peptide mixtures via isoelectric focusing (IEF) on a digital ProteomeChip (dPC) for SRM quantitation using a triple quadrupole (QQQ) instrument with an LC-Chip (Chip/Chip/SRM). To demonstrate the value of this approach, the optimization of the Chip/Chip/SRM platform was performed using prostate specific antigen (PSA) added to female plasma as a model system. The combination of immunodepletion of albumin and IgG with peptide fractionation on the dPC, followed by SRM analysis, resulted in a limit of quantitation of PSA added to female plasma at the level of ∼1-2.5 ng/mL with a CV of ∼13%. The optimized platform was applied to measure levels of PSA in plasma of a small cohort of male patients with prostate cancer (PCa) and healthy matched controls with concentrations ranging from 1.5 to 25 ng/mL. A good correlation (r(2) = 0.9459) was observed between standard clinical ELISA tests and the SRM-based assay. Our data demonstrate that the combination of IEF on the dPC and SRM (Chip/Chip/SRM) can be successfully applied for verification of low abundance protein biomarkers in complex samples.

  3. Raccoon abundance inventory report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the results of a raccoon abundance inventory on Clarence Cannon National Wildlife Refuge in 2012. Determining raccoon abundance allows for...

  4. Sunspots, Starspots, and Elemental Abundances

    Science.gov (United States)

    Doschek, George A.; Warren, Harry P.

    2017-08-01

    The composition of plasma in solar and stellar atmospheres is not fixed, but varies from feature to feature. These variations are organized by the First Ionization Potential (FIP) of the element. Solar measurements often indicate that low FIP elements (10 eV, such as C, N, O, Ar, He) compared to abundances in the photosphere. Stellar observations have also shown similar enrichments. An inverse FIP effect, where the low FIP elements are depleted, has been observed in stellar coronae of stars believed to have large starspots in their photospheres. The abundances are important for determining radiative loss rates in models, tracing the origin of the slow solar wind, and for understanding wave propagation in the chromosphere and corona. Recently, inverse FIP effects have been discovered in the Sun (Doschek, Warren, & Feldman 2015, ApJ, 808, L7) from spectra obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. The inverse FIP regions seem always to be near sunspots and cover only a very small area (characteristic length = a few arcseconds). However, in pursuing the search for inverse FIP regions, we have found that in some sunspot groups the coronal abundance at a temperature of 3-4 MK can be near photospheric over much larger areas of the sun near the sunspots (e.g., 6,000 arcsec2). Also, sometimes the abundances at 3-4 MK are in between coronal and photospheric values. This can occur in small areas of an active region. It is predicted (Laming 2015, Sol. Phys., 12, 2) that the FIP effect should be highly variable in the corona. Several examples of coronal abundance variations are presented. Our work indicates that a comprehensive re-investigation of solar abundances is highly desirable. This work is supported by a NASA Hinode grant.

  5. Usefulness of biopsying the major duodenal papilla to diagnose autoimmune pancreatitis: A prospective study using TgG4-immunostaining

    Institute of Scientific and Technical Information of China (English)

    Terumi Kamisawa; Yuyang Tu; Hitoshi Nakajima; Naoto Egawa; Kouji Tsuruta; Atsutake Okamoto

    2006-01-01

    AIM: To examine the histological and immunohistochemical findings of biopsy specimens taken from the major duodenal papilla of autoirnrnune pancreatitis (AIP)patients.METHODS: The major duodenal papilla in the resected pancreas of 3 patients with AIP and of 5 control patients [pancreatic carcinoma (n = 3) and chronic alcoholic pancreatitis (n = 2)] was irnrnunostained using anti-CD4-T cell, CD8-T cell and IgG4 antibodies. Forceps biopsy specimens taken from the major duodenal papilla of 2patients with AIP and 5 control patients with suspected papillitis were prospectively taken during duodenoscopy and immunohistochernically examined.RESULTS: Moderate or severe lyrnphoplasrnacytic infiltration including many CD4-positive or CD8-positive T lymphocytes and IgG4-positive plasma cells (≥10/HPF),was observed in the major duodenal papilla of all 3 patients with AIP. The same findings were also detected in the biopsy specimens taken from the major duodenal papilla of 2 patients with AIP, but in controls, there were only a few (≤3/HPF) IgG4-positive plasma cells infiltrating the major duodenal papilla.CONCLUSIONS: An abundant infiltration of IgG4-positive plasma cells is specifically detected in the major duodenal papilla of patients with AIP. Although this is a preliminary study, IgG4-irnmunostaining of biopsy specimens taken from the major duodenal papilla may support the diagnosis of AIP.

  6. Collisionless plasmas in astrophysics

    CERN Document Server

    Belmont, Gerard; Mottez, Fabrice; Pantellini, Filippo; Pelletier, Guy

    2013-01-01

    Collisionless Plasmas in Astrophysics examines the unique properties of media without collisions in plasma physics. Experts in this field, the authors present the first book to concentrate on collisionless conditions in plasmas, whether close or not to thermal equilibrium. Filling a void in scientific literature, Collisionless Plasmas in Astrophysics explains the possibilities of modeling such plasmas, using a fluid or a kinetic framework. It also addresses common misconceptions that even professionals may possess, on phenomena such as "collisionless (Landau) damping". Abundant illustrations

  7. Precision Chemical Abundance Measurements

    DEFF Research Database (Denmark)

    Yong, David; Grundahl, Frank; Meléndez, Jorge;

    2012-01-01

    This talk covers preliminary work in which we apply a strictly differential line-by-line chemical abundance analysis to high quality UVES spectra of the globular cluster NGC 6752. We achieve extremely high precision in the measurement of relative abundance ratios. Our results indicate that the ob......This talk covers preliminary work in which we apply a strictly differential line-by-line chemical abundance analysis to high quality UVES spectra of the globular cluster NGC 6752. We achieve extremely high precision in the measurement of relative abundance ratios. Our results indicate...... that the observed abundance dispersion exceeds the measurement uncertainties and that many pairs of elements show significant correlations when plotting [X1/H] vs. [X2/H]. Our tentative conclusions are that either NGC 6752 is not chemically homogeneous at the ~=0.03 dex level or the abundance variations...

  8. The Origin of Element Abundance Variations in Solar Energetic Particles

    Science.gov (United States)

    Reames, Donald V.

    2016-08-01

    Abundance enhancements, during acceleration and transport in both gradual and impulsive solar energetic particle (SEP) events, vary approximately as power laws in the mass-to-charge ratio [A/Q] of the ions. Since the Q-values depend upon the electron temperature of the source plasma, this has allowed a determination of this temperature from the pattern of element-abundance enhancements and a verification of the expected inverse-time dependence of the power of A/Q for diffusive transport of ions from the SEP events, with scattering mean free paths found to be between 0.2 and 1 AU. SEP events derived from plasma of different temperatures map into different regions in typical cross-plots of abundances, spreading the distributions. In comparisons of SEP events with temperatures above 2 MK, impulsive events show much broader non-thermal variation of abundances than do gradual events. The extensive shock waves accelerating ions in gradual events may average over much of an active region where numerous but smaller magnetic reconnections, "nanojets", produce suprathermal seed ions, thus averaging over varying abundances, while an impulsive SEP event only samples one local region of abundance variations. Evidence for a reference He/O-abundance ratio of 91, rather than 57, is also found for the hotter plasma. However, while this is similar to the solar-wind abundance of He/O, the solar-wind abundances otherwise provide an unacceptably poor reference for the SEP-abundance enhancements, generating extremely large errors.

  9. OXYGEN ABUNDANCES IN CEPHEIDS

    Energy Technology Data Exchange (ETDEWEB)

    Luck, R. E.; Andrievsky, S. M. [Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7215 (United States); Korotin, S. N.; Kovtyukh, V. V., E-mail: luck@fafnir.astr.cwru.edu, E-mail: serkor@skyline.od.ua, E-mail: val@deneb1.odessa.ua, E-mail: scan@deneb1.odessa.ua [Department of Astronomy and Astronomical Observatory, Odessa National University, Isaac Newton Institute of Chile, Odessa Branch, Shevchenko Park, 65014 Odessa (Ukraine)

    2013-07-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  10. Construction of a two-dimensional liquid chromatography separation system for high abundance proteins depletion in human plasma%去除血浆中高丰度蛋白质的二维液相色谱体系的建立

    Institute of Scientific and Technical Information of China (English)

    朱绍春; 张学洋; 高明霞; 晏国全; 张祥民

    2011-01-01

    High abundance proteins existing in human plasma severely impede the detection of low abundance proteins. This is one of the most difficult problems encountered in plasma pro-teomics research. We developed a two-dimensional liquid chromatography system with strong anion exchange chromatography-reversed-phase liquid chromatography ( SAX-RPLC) for the extensive separation of plasma proteins and selective depletion of high abundance proteins. TSKgel SuperQ-5PW was selected as the first dimensional separation column for crude human plasma fractionation and Jupiter C4 column was selected as the second dimensional separation column. Separation gradients of the two-dimensional liquid chromatography system were optimized to ensure an extensive separation of plasma proteins. Ten peaks with high signal intensities ( >20 mAU) at 215 nm during the second dimensional separation were collected and identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a result, 32 proteins, all of which were reported to be high abundance proteins in plasma, including human serum albumin (HAS), immunoglobulin G (IgG) and so on were successfully identified. This system provides an effective method for future depletion of more high abundance proteins and in-depth research in human plasma proteomics.%血浆中高丰度蛋白质的存在严重干扰低丰度蛋白质的检测,是困扰血浆蛋白质组学研究的技术瓶颈之一.针对这一热点问题,建立了一种二维液相色谱(强阴离子交换色谱-反相高效液相色谱)分离系统,对血浆中的高丰度蛋白质进行了色谱定位并进行去除.选择TSKgel SuperQ-5PW为第一维色谱分离柱,第二维色谱分离采用Jupiter C4柱,对第一维的馏分进行进一步的分离.通过梯度优化,血浆样品经过二维系统得到充分分离.第二维分离过程中从紫外信号强度高(215 nm,大于20 mAU)的峰中选择10个峰,利用液相色谱-串联质谱鉴定出32种高丰度蛋白质,

  11. Measurements of Absolute Abundances in Solar Flares

    CERN Document Server

    Warren, Harry P

    2013-01-01

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO). EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias ($f$). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is $...

  12. Deuterium abundance and cosmology

    CERN Document Server

    Vidal-Madjar, A; Lemoine, M

    1996-01-01

    We review the status of the measurements of the deuterium abundance from the local interstellar medium to the solar system and high redshifts absorbers toward quasars. We present preliminary results toward a white dwarf and a QSO. We conclude that the deuterium evolution from the Big-Bang to now is still not properly understood.

  13. Coronae of Stars with Supersolar Elemental Abundances

    Science.gov (United States)

    Peretz, Uria; Behar, Ehud; Drake, Stephen A.

    2015-01-01

    Coronal elemental abundances are known to deviate from the photospheric values of their parent star, with the degree of deviation depending on the first ionization potential (FIP). This study focuses on the coronal composition of stars with supersolar photospheric abundances. We present the coronal abundances of six such stars: 11 LMi, iota Hor, HR 7291, tau Boo, and alpha Cen A and B. These stars all have high-statistics X-ray spectra, three of which are presented for the first time. The abundances we measured were obtained using the line-resolved spectra of the Reflection Grating Spectrometer (RGS) in conjunction with the higher throughput EPIC-pn camera spectra onboard the XMM-Newton observatory. A collisionally ionized plasma model with two or three temperature components is found to represent the spectra well. All elements are found to be consistently depleted in the coronae compared to their respective photospheres. For 11 LMi and tau Boo no FIP effect is present, while iota Hor, HR 7291, and alpha Cen A and B show a clear FIP trend. These conclusions hold whether the comparison is made with solar abundances or the individual stellar abundances. Unlike the solar corona, where low-FIP elements are enriched, in these stars the FIP effect is consistently due to a depletion of high-FIP elements with respect to actual photospheric abundances. A comparison with solar (instead of stellar) abundances yields the same fractionation trend as on the Sun. In both cases, a similar FIP bias is inferred, but different fractionation mechanisms need to be invoked.

  14. Analysis of Isotopic Abundance of Plutonium by Multicollector-Inductively Coupled Plasma Mass Spectrometry%多接收电感耦合等离子体质谱法测量痕量钚同位素

    Institute of Scientific and Technical Information of China (English)

    张继龙; 王同兴; 李力力; 常志远; 赵永刚; 刘俊岭

    2005-01-01

    The isotopic analysis of 232Pu plutonium in 5×10-12 g/g samples using a multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) is described. IRMM-290b and uranium (UTB750) were used to correct the metrical data, and the analytical precision is about 0.5%.

  15. Administration of Exogenous Growth Hormone Is Associated with Changes in Plasma and Intracellular Mammary Amino Acid Profiles and Abundance of the Mammary Gland Amino Acid Transporter SLC3A2 in Mid-Lactation Dairy Cows

    OpenAIRE

    Quentin L Sciascia; David Pacheco; McCoard, Susan A.

    2015-01-01

    The objectives of this study were to (1) identify changes in plasma and mammary intracellular amino acid (AA) profiles in dairy cows treated with growth hormone (GH), and (2) evaluate the expression of mammary gland genes involved in the transport of AA identified in (1). Eight non-pregnant (n = 4 per group) lactating dairy cows were treated with a single subcutaneous injection of either a slow-release formulation of commercially available GH (Lactotropin 500 mg) or physiological saline solut...

  16. Increased IgG4 responses to multiple food and animal antigens indicate a polyclonal expansion and differentiation of pre-existing B cells in IgG4-related disease

    OpenAIRE

    Culver, EL; Vermeulen, E.; Makuch, M; Leeuwen, A. van; Sadler, R.; Cargill, T; Klenerman, P; Aalberse, RC; van Ham, SM; Barnes, E; Rispens, T

    2015-01-01

    Background: IgG4-related disease (IgG4-RD) is a systemic fibroinflammatory condition, characterised by an elevated serum IgG4 concentration and abundant IgG4-positive plasma cells in the involved organs. An important question is whether the elevated IgG4 response is causal or a reflection of immune-regulatory mechanisms of the disease. Objectives: To investigate if the IgG4 response in IgG4-RD represents a generalised polyclonal amplification by examining the response to common environmental ...

  17. IgG4-Related Nasal Pseudotumor

    Directory of Open Access Journals (Sweden)

    L. K. Døsen

    2015-01-01

    Full Text Available IgG4-related disease is recognized as one form of autoimmune pancreatitis. During the last ten years, it has also been described in several other organs. We present two patients with lesions showing a histological picture of fibrosis and lymphoplasmacytic infiltrations with abundant IgG4 positive plasma cells at hitherto unreported symmetrical nasal locations. The symmetrical complex consisted of one central lesion in the anterior nasal septum and the two others in each of the lateral nasal walls. The lesions extended from the anterior part of the inferior concha into the vestibulum and caused severe nasal obstruction.

  18. Absolute Abundance Measurements in Solar Flares

    Science.gov (United States)

    Warren, Harry

    2014-06-01

    We present measurements of elemental abundances in solar flares with EVE/SDO and EIS/Hinode. EVE observes both high temperature Fe emission lines Fe XV-XXIV and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (F). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is F=1.17+-0.22. Furthermore, we have compared the EVE measurements with corresponding flare observations of intermediate temperature S, Ar, Ca, and Fe emission lines taken with EIS. Our initial calculations also indicate a photospheric composition for these observations. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation in the non-flaring corona occurs.

  19. Measurements of Absolute Abundances in Solar Flares

    Science.gov (United States)

    Warren, Harry P.

    2014-05-01

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory. EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (f). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is f = 1.17 ± 0.22. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation occurs.

  20. Abundance, Excess, Waste

    Directory of Open Access Journals (Sweden)

    Rox De Luca

    2016-02-01

    Her recent work focuses on the concepts of abundance, excess and waste. These concerns translate directly into vibrant and colourful garlands that she constructs from discarded plastics collected on Bondi Beach where she lives. The process of collecting is fastidious, as is the process of sorting and grading the plastics by colour and size. This initial gathering and sorting process is followed by threading the components onto strings of wire. When completed, these assemblages stand in stark contrast to the ease of disposability associated with the materials that arrive on the shoreline as evidence of our collective human neglect and destruction of the environment around us. The contrast is heightened by the fact that the constructed garlands embody the paradoxical beauty of our plastic waste byproducts, while also evoking the ways by which those byproducts similarly accumulate in randomly assorted patterns across the oceans and beaches of the planet.

  1. Primordial Deuterium Abundance Measurements

    CERN Document Server

    Levshakov, S A; Takahara, F; Levshakov, Sergei A.; Kegel, Wilhelm H.; Takahara, Fumio

    1997-01-01

    Deuterium abundances measured recently from QSO absorption-line systems lie in the range from 3 10^{-5} to 3 10^{-4}, which shed some questions on standard big bang theory. We show that this discordance may simply be an artifact caused by inadequate analysis ignoring spatial correlations in the velocity field in turbulent media. The generalized procedure (accounting for such correlations) is suggested to reconcile the D/H measurements. An example is presented based on two high-resolution observations of Q1009+2956 (low D/H) [1,2] and Q1718+4807 (high D/H) [8,9]. We show that both observations are compatible with D/H = 4.1 - 4.6 10^{-5}, and thus support SBBN. The estimated mean value = 4.4 10^{-5} corresponds to the baryon-to-photon ratio during SBBN eta = 4.4 10^{-10} which yields the present-day baryon density Omega_b h^2 = 0.015.

  2. Immunglobulin G4-relateret sygdom er en ny inflammatorisk sygdom

    DEFF Research Database (Denmark)

    Næser, Esben Kure; Marcussen, Niels; Gregersen, Jon Waarst

    2012-01-01

    IgG4-related disease is a newly recognized inflammatory disease characterized by tissue infiltrates of IgG4 positive plasma cells. The disease was first recognized in pancreas but has now been described in nearly every organ. The diagnosis is based on the presence of dense lymphoplasmocytic...... infiltrates rich in IgG4 positive plasma cells. We describe a case of a 76-year-old man with IgG4-related disease involving the kidneys....

  3. Autoimmune pancreatitis--recent advances.

    Science.gov (United States)

    Novotný, I; Díte, P; Lata, J; Nechutová, H; Kianicka, B

    2010-01-01

    Autoimmune pancreatitis (AIP) is recognized as a distinct clinical entity, identified as a chronic inflammatory process of the pancreas in which the autoimmune mechanism is involved. Clinically and histologically, AIP has two subsets: type 1--lymphoplasmatic sclerosing pancreatitis with abundant infiltration of the pancreas and other affected organs with immunoglobulin G4-positive plasma cells, and type 2--duct centric fibrosis, characterized by granulocyte epithelial lesions in the pancreas without systemic involvement. In the diagnosis of AIP, two diagnostic criterions are used--the HISORt criteria and Asian Diagnostic Criteria. In the differential diagnosis, the pancreatic cancer must be excluded by endosonographically guided pancreatic biopsy. Typical signs of AIP are concomitant disorders in other organs (kidney, liver, biliary tract, salivary glands, colon, retroperitoneum, prostate). Novel clinicopathological entity was proposed as an 'IgG4-related sclerosing disease' (IgG4-RSC). Extensive IgG4-positive plasma cells and T lymphocyte infiltration is a common characteristics of this disease. Recently, IgG4-RSC syndrome was extended to a new entity, characterized by IgG4 hypergammaglobulinemia and IgG4-positive plasma cell infiltration, this being considered an expression of a lymphoproliferative disease, 'IgG4-positive multiorgan lymphoproliferative syndrome'. This syndrome includes Mikulicz's disease, mediastinal fibrosis, autoimmune hypophysitis, and inflammatory pseudotumor--lung, liver, breast. In the therapy of AIP, steroids constitute first-choice treatment. High response to the corticosteroid therapy is an important diagnostic criterion. In the literature, there are no case-control studies that determine if AIP predisposes to pancreatic cancer. Undoubtedly, AIP is currently a hot topic in pancreatology.

  4. Relative Abundance Measurements in Plumes and Interplumes

    CERN Document Server

    Guennou, Chloé; Savin, Daniel Wolf

    2015-01-01

    We present measurements of relative elemental abundances in plumes and interplumes. Plumes are bright, narrow structures in coronal holes that extend along open magnetic field lines far out into the corona. Previous work has found that in some coronal structures the abundances of elements with a low first ionization potential (FIP) 10 eV). We have used EIS spectroscopic observations made on 2007 March 13 and 14 over an ~24 hour period to characterize abundance variations in plumes and interplumes. To assess their elemental composition, we have used a differential emission measure (DEM) analysis, which accounts for the thermal structure of the observed plasma. We have used lines from ions of iron, silicon, and sulfur. From these we have estimated the ratio of the iron and silicon FIP bias relative to that for sulfur. From the results, we have created FIP-bias-ratio maps. We find that the FIP-bias ratio is sometimes higher in plumes than in interplumes and that this enhancement can be time dependent. These res...

  5. Deuterium Abundance in Consciousness and Current Cosmology

    Science.gov (United States)

    Rauscher, Elizabeth A.

    We utilize the deuterium-hydrogen abundances and their role in setting limits on the mass and other conditions of cosmogenesis and cosmological evolution. We calculate the dependence of a set of physical variables such as density, temperature, energy mass, entropy and other physical variable parameters through the evolution of the universe under the Schwarzschild conditions as a function from early to present time. Reconciliation with the 3°K and missing mass is made. We first examine the Schwarzschild condition; second, the geometrical constraints of a multidimensional Cartesian space on closed cosmologies, and third we will consider the cosmogenesis and evolution of the universe in a multidimensional Cartesian space, obeying the Schwarzschild condition. Implications of this model for matter creation are made. We also examine experimental evidence for closed versus open cosmologies; x-ray detection of the "missing mass" density. Also the interstellar deuterium abundance, along with the value of the Hubble constant set a general criterion on the value of the curvature constant, k. Once the value of the Hubble constant, H is determined, the deuterium abundance sets stringent restrictions on the value of the curvature constant k by an detailed discussion is presented. The experimental evidences for the determination of H and the primary set of coupled equations to determine D abundance is given. 'The value of k for an open, closed, or flat universe will be discussed in terms of the D abundance which will affect the interpretation of the Schwarzschild, black hole universe. We determine cosmology solutions to Einstein's field obeying the Schwarzschild solutions condition. With this model, we can form a reconciliation of the black hole, from galactic to cosmological scale. Continuous creation occurs at the dynamic blackhole plasma field. We term this new model the multiple big bang or "little whimper model". We utilize the deuteriumhydrogen abundances and their role in

  6. [Two cases of IgG4-related disease with pleural effusion].

    Science.gov (United States)

    Suzuki, Nobuaki; Saeki, Takako; Shimaoka, Yuichi; Kuriyama, Hideyuki; Nishibori, Takeaki; Ebe, Yusuke; Sato, Kazuhiro

    2011-02-01

    We describe 2 cases of IgG4-related disease with pleural effusion in elderly men. Both patients had elevated serum IgG4 levels, and the characteristics of their pleural effusion were similar. Patient 1 had pericardial effusion and retroperitoneal fibrosis, and a biopsy specimen from the pericardium showed infiltration of abundant IgG4-positive plasma cells with fibrosis. Because his pleurisy, pericarditis and retroperitoneal fibrosis responded to steroid therapy, we diagnosed pleurisy associated with IgG4-related disease. Patient 2 had been treated with steroids because of IgG4-related sialadenitis and interstitial pneumonitis, but pleural effusion developed. Although histopathological examination of the pleura showed infiltration of abundant IgG4-positive plasma cells with fibrosis, Mycobacterium tuberculosis was cultured from the pleural effusion, and histologic examination also showed epithelioid granuloma. Chemotherapy for tuberculosis was effective for the pleurisy, and we diagnosed tuberculous pleurisy as a complication of IgG4-related disease. In cases of IgG4-related disease associated with pleural effusion, the clinical course should be considered together with the serum IgG4 levels and pleural histology.

  7. Gaseous abundances in M82

    CERN Document Server

    Ranalli, P; Origlia, L; Maiolino, R; Makishima, K; Ranalli, Piero; Comastri, Andrea; Origlia, Livia; Maiolino, Roberto; Makishima, Kazuo

    2005-01-01

    We present the preliminary analysis of a deep (100ks) XMM-Newton observation of M82. The spatial distribution of the abundances of chemical elements (Fe, O, Ne, Mg, Si, S) is investigated through narrow-band imaging analisys and spatially-resolved spectroscopy. We find that the abundances of alpha-elements follow a bipolar distribution, these elements being more abundant in the gaseous outflow than in the galaxy centre. This behaviour is found to be more marked for lighter elements (O, Ne) than for heavier elements.

  8. Chlorine Abundances in Cool Stars

    CERN Document Server

    Maas, Z G; Hinkle, K

    2016-01-01

    Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H$^{35}$Cl at 3.69851 $\\mu$m. The high resolution L-band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4m telescope. The average [$^{35}$Cl/Fe] abundance in stars with --0.72$<$[Fe/H]$<$0.20 is [$^{35}$Cl/Fe]=(--0.10$\\pm$0.15) dex. The mean difference between the [$^{35}$Cl/Fe] ratios measured in our stars and chemical evolution model values is (0.16$\\pm$0.15) dex. The [$^{35}$Cl/Ca] ratio has an offset of $\\sim$0.35 dex above model predictions suggesting chemical evolution models are under producing Cl at the high metallicity range. Abundances of C, N, O, Si, and Ca were also measured in our spectral region and are consistent with F and G dwarfs. The Cl versus O abundances from our sample match Cl abundances measured in planetary nebula and \\ion{H}{2} regions. In one star where both H$^{35}$Cl a...

  9. IgG4-related inflammatory pseudotumor of the renal pelvis involving renal parenchyma, mimicking malignancy.

    Science.gov (United States)

    Park, Ho Gyun; Kim, Kyoung Min

    2016-01-22

    IgG4-related disease is a recently recognized systemic disease characterized by storiform fibrosis with infiltration of IgG4-positive plasma cells. In rare incidences, IgG4-related renal disease can present as a solitary mass lesion at renal pelvis and can pose a diagnostic challenge since these lesions mimic malignancy. Herein, we present a rare case of IgG4-related disease presenting as inflammatory pseudotumor lesion, involving the renal pelvis and also neighboring renal parenchyma. A 75-year-old man with no history of IgG4-related disease underwent computed tomography (CT) scan for evaluation of prostatic cancer. The CT scan incidentally revealed a mass lesion located at the right renal pelvis. Radiologic findings were highly suggestive of malignancy. Therefore, the patient underwent right nephroureterectomy. Microscopically, the mass lesion showed storiform fibrosis with diffuse and intense inflammatory cell infiltration. Infiltrating cells were mainly histiocytes and plasma cells. Tubulointerstitium adjacent to the lesion also showed fibrosis with abundant plasmacytic infiltration. Immunohistochemical staining revealed the presence of IgG4-positive plasma cells in both the mass lesion and tubulointerstitium (mean of 94/HPF per field). Considering these findings, we diagnosed the mass lesion as IgG4-related inflammatory pseudotumor of the renal pelvis. In patients with renal pelvic masses, IgG4-related inflammatory pesudotumor should be considered in the differential diagnosis to avoid unnecessary surgical intervention.

  10. Anthropogenic noise changes arthropod abundances.

    Science.gov (United States)

    Bunkley, Jessie P; McClure, Christopher J W; Kawahara, Akito Y; Francis, Clinton D; Barber, Jesse R

    2017-05-01

    Anthropogenic noise is a widespread and growing form of sensory pollution associated with the expansion of human infrastructure. One specific source of constant and intense noise is that produced by compressors used for the extraction and transportation of natural gas. Terrestrial arthropods play a central role in many ecosystems, and given that numerous species rely upon airborne sounds and substrate-borne vibrations in their life histories, we predicted that increased background sound levels or the presence of compressor noise would influence their distributions. In the second largest natural gas field in the United States (San Juan Basin, New Mexico, USA), we assessed differences in the abundances of terrestrial arthropod families and community structure as a function of compressor noise and background sound level. Using pitfall traps, we simultaneously sampled five sites adjacent to well pads that possessed operating compressors, and five alternate, quieter well pad sites that lacked compressors, but were otherwise similar. We found a negative association between sites with compressor noise or higher levels of background sound and the abundance of five arthropod families and one genus, a positive relationship between loud sites and the abundance of one family, and no relationship between noise level or compressor presence and abundance for six families and two genera. Despite these changes, we found no evidence of community turnover as a function of background sound level or site type (compressor and noncompressor). Our results indicate that anthropogenic noise differentially affects the abundances of some arthropod families. These preliminary findings point to a need to determine the direct and indirect mechanisms driving these observed responses. Given the diverse and important ecological functions provided by arthropods, changes in abundances could have ecological implications. Therefore, we recommend the consideration of arthropods in the environmental

  11. Hf Transition Probabilities and Abundances

    CERN Document Server

    Lawler, J E; Labby, Z E; Sneden, C; Cowan, J J; Ivans, I I

    2006-01-01

    Radiative lifetimes from laser-induced fluorescence measurements, accurate to about +/- 5 percent, are reported for 41 odd-parity levels of Hf II. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf II. Approximately half of these new transition probabilities overlap with recent independent measurements using a similar approach. The two sets of measurements are found to be in good agreement for measurements in common. Our new laboratory data are applied to refine the hafnium photospheric solar abundance and to determine hafnium abundances in 10 metal-poor giant stars with enhanced r-process abundances. For the Sun we derive log epsilon (Hf) = 0.88 +/- 0.08 from four lines; the uncertainty is dominated by the weakness of the lines and their blending by other spectral features. Within the uncertainties of our analysis, the r-process-rich stars possess constant Hf/La and Hf/Eu abundance ratios, log epsilon (Hf...

  12. Gd Transition Probabilities and Abundances

    CERN Document Server

    Den Hartog, E A; Sneden, C; Cowan, J J

    2006-01-01

    Radiative lifetimes, accurate to +/- 5%, have been measured for 49 even-parity and 14 odd-parity levels of Gd II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 611 lines of Gd II. This work is the largest-scale laboratory study to date of Gd II transition probabilities and the first using a high performance Fourier transform spectrometer. This improved data set has been used to determine a new solar photospheric Gd abundance, log epsilon = 1.11 +/- 0.03. Revised Gd abundances have also been derived for the r-process-rich metal-poor giant stars CS 22892-052, BD+17 3248, and HD 115444. The resulting Gd/Eu abundance ratios are in very good agreement with the solar-system r-process ratio. We have employed the increasingly accurate stellar abundance determinations, resulting in large part from the more precise laboratory atomic data, to predict directly the Solar System r-process elemental...

  13. Lightest sterile neutrino abundance within the nuMSM

    OpenAIRE

    Asaka, Takehiko; Laine, Mikko; Shaposhnikov, Mikhail

    2006-01-01

    We determine the abundance of the lightest (dark matter) sterile neutrinos created in the Early Universe due to active-sterile neutrino transitions from the thermal plasma. Our starting point is the field-theoretic formula for the sterile neutrino production rate, derived in our previous work [JHEP 06(2006)053], which allows to systematically incorporate all relevant effects, and also to analyse various hadronic uncertainties. Our numerical results differ moderately from previous computations...

  14. Coho Abundance - Linear Features [ds183

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  15. Steelhead Abundance - Point Features [ds184

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  16. Steelhead Abundance - Linear Features [ds185

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  17. Coho Abundance - Point Features [ds182

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  18. Chinook Abundance - Point Features [ds180

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  19. Abundance estimation and Conservation Biology

    Directory of Open Access Journals (Sweden)

    Nichols, J. D.

    2004-06-01

    Full Text Available Abundance is the state variable of interest in most population–level ecological research and in most programs involving management and conservation of animal populations. Abundance is the single parameter of interest in capture–recapture models for closed populations (e.g., Darroch, 1958; Otis et al., 1978; Chao, 2001. The initial capture–recapture models developed for partially (Darroch, 1959 and completely (Jolly, 1965; Seber, 1965 open populations represented efforts to relax the restrictive assumption of population closure for the purpose of estimating abundance. Subsequent emphases in capture–recapture work were on survival rate estimation in the 1970’s and 1980’s (e.g., Burnham et al., 1987; Lebreton et al.,1992, and on movement estimation in the 1990’s (Brownie et al., 1993; Schwarz et al., 1993. However, from the mid–1990’s until the present time, capture–recapture investigators have expressed a renewed interest in abundance and related parameters (Pradel, 1996; Schwarz & Arnason, 1996; Schwarz, 2001. The focus of this session was abundance, and presentations covered topics ranging from estimation of abundance and rate of change in abundance, to inferences about the demographic processes underlying changes in abundance, to occupancy as a surrogate of abundance. The plenary paper by Link & Barker (2004 is provocative and very interesting, and it contains a number of important messages and suggestions. Link & Barker (2004 emphasize that the increasing complexity of capture–recapture models has resulted in large numbers of parameters and that a challenge to ecologists is to extract ecological signals from this complexity. They offer hierarchical models as a natural approach to inference in which traditional parameters are viewed as realizations of stochastic processes. These processes are governed by hyperparameters, and the inferential approach focuses on these hyperparameters. Link & Barker (2004 also suggest that

  20. Abundance estimation and conservation biology

    Science.gov (United States)

    Nichols, J.D.; MacKenzie, D.I.

    2004-01-01

    Abundance is the state variable of interest in most population–level ecological research and in most programs involving management and conservation of animal populations. Abundance is the single parameter of interest in capture–recapture models for closed populations (e.g., Darroch, 1958; Otis et al., 1978; Chao, 2001). The initial capture–recapture models developed for partially (Darroch, 1959) and completely (Jolly, 1965; Seber, 1965) open populations represented efforts to relax the restrictive assumption of population closure for the purpose of estimating abundance. Subsequent emphases in capture–recapture work were on survival rate estimation in the 1970’s and 1980’s (e.g., Burnham et al., 1987; Lebreton et al.,1992), and on movement estimation in the 1990’s (Brownie et al., 1993; Schwarz et al., 1993). However, from the mid–1990’s until the present time, capture–recapture investigators have expressed a renewed interest in abundance and related parameters (Pradel, 1996; Schwarz & Arnason, 1996; Schwarz, 2001). The focus of this session was abundance, and presentations covered topics ranging from estimation of abundance and rate of change in abundance, to inferences about the demographic processes underlying changes in abundance, to occupancy as a surrogate of abundance. The plenary paper by Link & Barker (2004) is provocative and very interesting, and it contains a number of important messages and suggestions. Link & Barker (2004) emphasize that the increasing complexity of capture–recapture models has resulted in large numbers of parameters and that a challenge to ecologists is to extract ecological signals from this complexity. They offer hierarchical models as a natural approach to inference in which traditional parameters are viewed as realizations of stochastic processes. These processes are governed by hyperparameters, and the inferential approach focuses on these hyperparameters. Link & Barker (2004) also suggest that our attention

  1. The Origin of Element Abundance Variations in Solar Energetic Particles

    CERN Document Server

    Reames, Donald V

    2016-01-01

    Abundance enhancements, during acceleration and transport in both gradual and impulsive solar energetic particle (SEP) events, vary approximately as power laws in the mass-to-charge ratio A/Q of the ions. Since the Q values depend upon the electron temperature of the source plasma, this has allowed a determination of this temperature from the pattern of element abundance enhancements and a verification of the expected inverse-time dependence of the power of A/Q for diffusive transport of ions from the SEP events, with scattering mean free paths found to be between 0.2 and 1 AU. SEP events derived from plasma of different temperatures map into different regions in typical cross-plots of abundances, spreading the distributions. In comparisons of SEP events with temperatures above 2 MK, impulsive events show much broader non-thermal variation of abundances than do gradual events. The extensive shock waves accelerating ions in gradual events may average over much of an active region where numerous but smaller mag...

  2. Sm Transition Probabilities and Abundances

    CERN Document Server

    Lawler, J E; Sneden, C; Cowan, J J

    2005-01-01

    Radiative lifetimes, accurate to +/- 5%, have been measured for 212 odd-parity levels of Sm II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier-transform spectrometry to determine transition probabilities for more than 900 lines of Sm II. This work is the largest-scale laboratory study to date of Sm II transition probabilities using modern methods. This improved data set has been used to determine a new solar photospheric Sm abundance, log epsilon = 1.00 +/- 0.03, from 26 lines. The spectra of three very metal-poor, neutron-capture-rich stars also have been analyzed, employing between 55 and 72 Sm II lines per star. The abundance ratios of Sm relative to other rare earth elements in these stars are in agreement, and are consistent with ratios expected from rapid neutron-capture nucleosynthesis (the r-process).

  3. Element abundances at high redshift

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, D.M.; Welty, D.E.; York, D.G. (Northwestern Univ., Evanston, IL (USA); Chicago Univ., IL (USA))

    1989-08-01

    Abundances of Si(+), S(+), Cr(+), Mn(+), Fe( ), and Zn(+) are considered for two absorption-line systems in the spectrum of the QSO PKS 0528 - 250. Zinc and sulfur are underabundant, relative to H, by a factor of 10 compared to their solar and Galactic interstellar abundances. The silicon-, chromium-, iron-, and nickel-to-hydrogen ratios are less than the solar values and comparable to the local interstellar ratios. A straightforward interpretation is that nucleosynthesis in these high-redshift systems has led to only about one-tenth as much heavy production as in the gas clouds around the sun, and that the amount of the observed underabundances attributable to grain depletion is small. The dust-to-gas ratio in these clouds is less than 8 percent of the Galactic value. 25 refs.

  4. Element abundances at high redshift

    Science.gov (United States)

    Meyer, David M.; Welty, D. E.; York, D. G.

    1989-01-01

    Abundances of Si(+), S(+), Cr(+), Mn(+), Fe(_), and Zn(+) are considered for two absorption-line systems in the spectrum of the QSO PKS 0528 - 250. Zinc and sulfur are underabundant, relative to H, by a factor of 10 compared to their solar and Galactic interstellar abundances. The silicon-, chromium-, iron-, and nickel-to-hydrogen ratios are less than the solar values and comparable to the local interstellar ratios. A straightforward interpretation is that nucleosynthesis in these high-redshift systems has led to only about one-tenth as much heavy production as in the gas clouds around the sun, and that the amount of the observed underabundances attributable to grain depletion is small. The dust-to-gas ratio in these clouds is less than 8 percent of the Galactic value.

  5. Abundance analysis of Barium stars

    Institute of Scientific and Technical Information of China (English)

    Guo-Qing Liu; Yan-Chun Liang; Li-Cai Deng

    2009-01-01

    We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution Echelle spectra. The neu- tron capture process elements Y, Zr, Ba, La and Eu show obvious overabundances relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, in- cluding Na, Mg, A1, Si, Ca, Sc, Ti, V, Cr, Mn and Ni, show comparable abundances to the Solar ones, and their [Fe/H] covers a range from -0.40 to 0.21, which means they belong to the Galactic disk. The predictions of the theoretical model of wind accretion for bi- nary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of present-day white dwarf companions in binary systems.

  6. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  7. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  8. The role of IgG4 (+) plasma cells in the association of Hashimoto's thyroiditis with papillary carcinoma.

    Science.gov (United States)

    Taşli, Funda; Ozkök, Güliz; Argon, Asuman; Ersöz, Didem; Yağci, Ayşe; Uslu, Adam; Erkan, Nazif; Salman, Tarik; Vardar, Enver

    2014-12-01

    Hashimoto's thyroiditis (HT) is considered to be a risk factor for the formation of papillary carcinoma. The association of IgG4-related sclerosing disease with tumor is reported to be as sporadic cases in many organs. In this study, it was intended to re-classify the HT diagnosed cases on the basis of the existence of IgG4 (+) plasma cells; to investigate the clinicopathologic and histopathologic features of the both groups; and in addition, to evaluate the papillary carcinoma prevalence in IgG4 (+) and IgG4 (-) HT cases as well as the prognostic parameters between these groups. Totally 59 cases between the years 2008-2013, 29 of which contain Hashimoto thyroiditis diagnosis in total thyroidectomy materials, and 30 of which contain the diagnosis of HT+papillary carcinoma, were included in the study. The materials were immunohistochemically applied IgG and IgG4; and the cases were classified in two groups as IgG4-positive HT and IgG4-negative HT containing cases, on the basis of IgG4/IgG rate. All histopathologic and clinicopathologic parameters between these two groups, as well as their association with papillary carcinoma were investigated. Thirty eight (64.4%) of total 59 cases were NonIgG4 thyroiditis, and 21 (35.5%) were IgG4 thyroiditis. Tumors were detected in 14 (36.8%) of the NonIgG4 thyroiditis cases, and in 16 (76.1%) of the IgG4 thyroiditis cases. The association of IgG4 thyroiditis with tumor is statistically significant (p thyroiditis cases. Perithyroidal extension was detected in six of the cases with tumor, and five of the six cases were IgG4 thyroiditis cases. The association of IgG4 (+) HT cases with increased papillary carcinoma prevalence is suggestive of that IgG4 (+) plasma cells can play a role in carcinogenesis in papillary carcinomas developed in HTs, without a chronic sclerosing ground. In addition, although the number of cases is limited, the high-association of IgG4 (+) plasma cells with adverse prognostic parameters such as

  9. Lead abundance in the uranium star CS 31082-001

    DEFF Research Database (Denmark)

    Plez, B.; Hill, V.; Cayrel, R.

    2004-01-01

    stars:abundances- physical data and processes: nuclear reactions, nucleosynthesis, abundances- atomic data......stars:abundances- physical data and processes: nuclear reactions, nucleosynthesis, abundances- atomic data...

  10. Surface abundances of ON stars

    CERN Document Server

    Martins, F; Palacios, A; Howarth, I; Georgy, C; Walborn, N R; Bouret, J -C; Barba, R

    2015-01-01

    Massive stars burn hydrogen through the CNO cycle during most of their evolution. When mixing is efficient, or when mass transfer in binary systems happens, chemically processed material is observed at the surface of O and B stars. ON stars show stronger lines of nitrogen than morphologically normal counterparts. Whether this corresponds to the presence of material processed through the CNO cycle or not is not known. Our goal is to answer this question. We perform a spectroscopic analysis of a sample of ON stars with atmosphere models. We determine the fundamental parameters as well as the He, C, N, and O surface abundances. We also measure the projected rotational velocities. We compare the properties of the ON stars to those of normal O stars. We show that ON stars are usually helium-rich. Their CNO surface abundances are fully consistent with predictions of nucleosynthesis. ON stars are more chemically evolved and rotate - on average - faster than normal O stars. Evolutionary models including rotation cann...

  11. Range of fractionated plasma products to optimize plasma resources

    Institute of Scientific and Technical Information of China (English)

    Thierry Burnouf

    2010-01-01

    @@ HUMAN PLASMA is a source material that is crucial for the production of unique therapeutic fractionated products. Indeed, plasma contains hundreds of proteins ensuring many physiological functions. The most abun-dant proteins, albumin and immunoglobulin G (IgG) ,are present at about 35 and 10 g/L,respectively,repre-senting about 80% of all plasma proteins. However,other important therapeutic proteins include the coagu-lation factors (factor Ⅷ (F Ⅷ) ; FIX ; Von Willebrand Factor (VWF), fibrinogen) various protease inhibitors (alpha 1-antitrypsin ; antithrombin; C1-esterase) and anticoagulants (protein C) which exhibit potent physi-ological activity.

  12. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  13. LITERATURE SURVEY ON ISOTOPIC ABUNDANCE RATIO MEASUREMENTS - 2001-2005

    Energy Technology Data Exchange (ETDEWEB)

    HOLDEN, N.E.

    2005-08-13

    Along with my usual weekly review of the published literature for new nuclear data, I also search for new candidates for best measurements of isotopic abundances from a single source. Most of the published articles, that I previously had found in the Research Library at the Brookhaven Lab, have already been sent to the members of the Atomic Weights Commission, by either Michael Berglund or Thomas Walczyk. In the last few days, I checked the published literature for any other articles in the areas of natural variations in isotopic abundance ratios, measurements of isotopic abundance ratios on samples of extra-terrestrial material and isotopic abundance ratio measurements performed using ICPMS instruments. Hopefully this information will be of interest to members of the Commission, the sub-committee on isotopic abundance measurements (SIAM), members of the former sub-committee on natural isotopic fractionation (SNIF), the sub-committee on extra-terrestrial isotope ratios (SETIR), the RTCE Task Group and the Guidelines Task Group, who are dealing with ICPMS and TIMS comparisons. In the following report, I categorize the publications in one of four areas. Measurements performed using either positive or negative ions with Thermal Ionization Mass Spectrometer, TIMS, instruments; measurements performed on Inductively Coupled Plasma Mass Spectrometer, ICPMS, instruments; measurements of natural variations of the isotopic abundance ratios; and finally measurements on extra-terrestrial samples with instrumentation of either type. There is overlap in these areas. I selected out variations and ET results first and then categorized the rest of the papers by TIMS and ICPMS.

  14. Stark broadening data for stellar plasma research.

    Science.gov (United States)

    Dimitrijević, M. S.

    Results of an effort to provide to astrophysicists and physicists an as much as possible complete set of Stark broadening parameters needed for stellar opacity calculations, stellar atmosphere modelling, abundance determinations and diagnostics of different plasmas in astrophysics, physics and plasma technology, are presented. Stark broadening has been considered within the semiclassical perturbation, and the modified semiempirical approaches.

  15. Abundance analysis of DAZ white dwarfs

    CERN Document Server

    Kawka, Adela; Dinnbier, Frantisek; Cibulkova, Helena; Nemeth, Peter

    2010-01-01

    We present an abundance analysis of a sample of 33 hydrogen-rich (DA) white dwarfs. We have used archival high-resolution spectra to measure abundances of calcium, magnesium and iron in a set of 30 objects. In addition, we present preliminary calcium abundances in three new white dwarfs based on low-dispersion spectra. We investigate some abundance ratios (Mg/Ca, Fe/Ca) that may help uncover the composition of the accretion source.

  16. Planetary nebulae abundances and stellar evolution

    NARCIS (Netherlands)

    Pottasch, S. R.; Bernard-Salas, J.

    2006-01-01

    A summary is given of planetary nebulae abundances from ISO measurements. It is shown that these nebulae show abundance gradients (with galactocentric distance), which in the case of neon, argon, sulfur and oxygen (with four exceptions) are the same as HII regions and early type star abundance gradi

  17. Planetary nebulae abundances and stellar evolution II

    NARCIS (Netherlands)

    Pottasch, S. R.; Bernard-Salas, J.

    2010-01-01

    Context. In recent years mid-and far infrared spectra of planetary nebulae have been analysed and lead to more accurate abundances. It may be expected that these better abundances lead to a better understanding of the evolution of these objects. Aims. The observed abundances in planetary nebulae are

  18. ELSA: An Integrated, Semi-Automated Nebular Abundance Package

    CERN Document Server

    Johnson, M D; Henry, R B C; Kwitter, K B

    2006-01-01

    We present ELSA, a new modular software package, written in C, to analyze and manage spectroscopic data from emission-line objects. In addition to calculating plasma diagnostics and abundances from nebular emission lines, the software provides a number of convenient features including the ability to ingest logs produced by IRAF's splot task, to semi-automatically merge spectra in different wavelength ranges, and to automatically generate various data tables in machine-readable or LaTeX format. ELSA features a highly sophisticated interstellar reddening correction scheme that takes into account temperature and density effects as well as He II contamination of the hydrogen Balmer lines. Abundance calculations are performed using a 5-level atom approximation with recent atomic data, based on R. Henry's ABUN program. Improvements planned in the near future include use of a three-region ionization model, similar to IRAF's nebular package, error propagation, and the addition of ultraviolet and infrared line analysi...

  19. Modeling the ion abundances in Saturn's inner magnetosphere

    Science.gov (United States)

    Fleshman, B. L.; Bagenal, F.; Delamere, P. A.

    2011-12-01

    Water ejected from Enceladus's plumes provides much of the material that fills both the dense H2O torus centered on Enceladus's orbit, as well as Saturn's neutral clouds which extend at least four times farther from Saturn. Photo- and impact ionization transforms a few percent of these neutrals into the ions co-rotating with Saturn's magnetosphere, and charge exchange is responsible for a substantial redistribution among the hydrogen and water-group ions, though it does not alter the overall plasma density. In this paper, we explore ion abundances at Saturn with a chemistry model developed to include all of these processes. Building on our earlier attempts, we now include a source of neutrals from a neutral cloud model, so as to advance our description to include radial and latitudinal variations. At the same time, we now prescribe a radially-varying plasma diffusion coefficient to study the magnetosphere's inability to contain centrifigually-unstable plasma. We also are interested in the effect of hot electrons (102-103 eV) beamed along field lines into the equatorial region chiefly of interest. Our parameter study of radial diffusion and hot-electron flux is anchored to available Cassini CAPS water-group and proton abundances. Preliminary results suggest an injection of ~10 MW by hot electrons, and reveal promising radial trends in the water-group abundances that agree well with Sittler et al. (2008). We can also simulate an Enceladus torus dominated H3O+ -- a result not obtainable prior to coupling the chemistry and neutral cloud models.

  20. Spatial Distribution of Element Abundances and Ionization States in Solar Energetic-Particle Events

    Science.gov (United States)

    Reames, Donald V.

    2017-08-01

    We have studied the spatial and temporal distribution of abundances of chemical elements in large "gradual" solar energetic-particle (SEP) events, and especially the source plasma temperatures, derived from those abundances, using measurements from the Wind and Solar TErrestrial RElations Observatory (STEREO) spacecraft, widely separated in solar longitude. A power-law relationship between abundance enhancements and mass-to-charge ratios [A/Q] of the ions can be used to determine Q-values and source plasma temperatures at remote spacecraft with instruments that were not designed for charge-state measurements. We search for possible source variations along the accelerating shock wave, finding one clear case where the accelerating shock wave appears to dispatch ions from 3.2± 0.8 MK plasma toward one spacecraft and those from 1.6± 0.2 MK plasma toward another, 116∘ away. The difference persists for three days and then fades away. Three other SEP events show less-extreme variation in source temperatures at different spacecraft, in one case observed over 222∘ in longitude. This initial study shows how the power-law relation between abundance enhancements and ion A/Q-values provides a new technique to determine Q and plasma temperatures in the seed population of SEP ions over a broad region of space using remote spacecraft with instruments that were not originally designed for measurements of ionization states.

  1. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  2. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  3. Origin of Cosmic Chemical Abundances

    CERN Document Server

    Maio, Umberto

    2015-01-01

    Cosmological N-body hydrodynamic computations following atomic and molecular chemistry (e$^-$, H, H$^+$, H$^-$, He, He$^+$, He$^{++}$, D, D$^+$, H$_2$, H$_2^+$, HD, HeH$^+$), gas cooling, star formation and production of heavy elements (C, N, O, Ne, Mg, Si, S, Ca, Fe, etc.) from stars covering a range of mass and metallicity are used to explore the origin of several chemical abundance patterns and to study both the metal and molecular content during simulated galaxy assembly. The resulting trends show a remarkable similarity to up-to-date observations of the most metal-poor damped Lyman-$\\alpha$ absorbers at redshift $z\\gtrsim 2$. These exhibit a transient nature and represent collapsing gaseous structures captured while cooling is becoming effective in lowering the temperature below $\\sim 10^4\\,\\rm K$, before they are disrupted by episodes of star formation or tidal effects. Our theoretical results agree with the available data for typical elemental ratios, such as [C/O], [Si/Fe], [O/Fe], [Si/O], [Fe/H], [O/...

  4. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may

  5. Climate and local abundance in freshwater fishes

    OpenAIRE

    Knouft, Jason H.; Anthony, Melissa M.

    2016-01-01

    Identifying factors regulating variation in numbers of individuals among populations across a species' distribution is a fundamental goal in ecology. A common prediction, often referred to as the abundant-centre hypothesis, suggests that abundance is highest near the centre of a species' range. However, because of the primary focus on the geographical position of a population, this framework provides little insight into the environmental factors regulating local abundance. While range-wide va...

  6. Abundance of introduced species at home predicts abundance away in herbaceous communities

    Science.gov (United States)

    Firn, Jennifer; Moore, Joslin L.; MacDougall, Andrew S.; Borer, Elizabeth T.; Seabloom, Eric W.; HilleRisLambers, Janneke; Harpole, W. Stanley; Cleland, Elsa E.; Brown, Cynthia S.; Knops, Johannes M.H.; Prober, Suzanne M.; Pyke, David A.; Farrell, Kelly A.; Bakker, John D.; O'Halloran, Lydia R.; Adler, Peter B.; Collins, Scott L.; D'Antonio, Carla M.; Crawley, Michael J.; Wolkovich, Elizabeth M.; La Pierre, Kimberly J.; Melbourne, Brett A.; Hautier, Yann; Morgan, John W.; Leakey, Andrew D.B.; Kay, Adam; McCulley, Rebecca; Davies, Kendi F.; Stevens, Carly J.; Chu, Cheng-Jin; Holl, Karen D.; Klein, Julia A.; Fay, Phillip A.; Hagenah, Nicole; Kirkman, Kevin P.; Buckley, Yvonne M.

    2011-01-01

    Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.

  7. Chemical abundances in Galactic Planetary Nebulae with Spitzer spectra

    CERN Document Server

    Garcia-Hernandez, D A

    2014-01-01

    We present new low-resolution (R~800) optical spectra of 22 Galactic PNe with Spitzer spectra. These data are combined with recent optical spectroscopic data available in the literature to construct representative samples of compact (and presumably young) Galactic disc and bulge PNe with Spitzer spectra. Attending to the nature of the dust features seen in their Spitzer spectra, Galactic disc and bulge PNe are classified according to four major dust types (oxygen chemistry or OC, carbon chemistry or CC, double chemistry or DC, featureless or F) and subtypes (amorphous and crystalline, and aliphatic and aromatic). Nebular gas abundances of He, N, O, Ne, S, Cl and Ar, as well as plasma parameters (e.g. Ne, Te) are homogeneously derived and we study the median chemical abundances and nebular properties in Galactic disc and bulge PNe depending on their Spitzer dust types and subtypes. A comparison of the derived median abundance patterns with AGB nucleosynthesis predictions show mainly that: i) DC PNe, both with ...

  8. Elemental abundances of Galactic bulge planetary nebulae from optical recombination lines

    CERN Document Server

    Wang, W

    2007-01-01

    (abridged) Deep long-slit optical spectrophotometric observations are presented for 25 Galactic bulge planetary nebulae (GBPNe) and 6 Galactic disk planetary nebulae (GDPNe). The spectra, combined with archival ultraviolet spectra obtained with the International Ultraviolet Explorer (IUE) and infrared spectra obtained with the Infrared Space Observatory (ISO), have been used to carry out a detailed plasma diagnostic and element abundance analysis utilizing both collisional excited lines (CELs) and optical recombination lines (ORLs). Comparisons of plasma diagnostic and abundance analysis results obtained from CELs and from ORLs reproduce many of the patterns previously found for GDPNe. In particular we show that the large discrepancies between electron temperatures (Te's) derived from CELs and from ORLs appear to be mainly caused by abnormally low values yielded by recombination lines and/or continua. Similarly, the large discrepancies between heavy element abundances deduced from ORLs and from CELs are large...

  9. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter

  10. Climate and local abundance in freshwater fishes.

    Science.gov (United States)

    Knouft, Jason H; Anthony, Melissa M

    2016-06-01

    Identifying factors regulating variation in numbers of individuals among populations across a species' distribution is a fundamental goal in ecology. A common prediction, often referred to as the abundant-centre hypothesis, suggests that abundance is highest near the centre of a species' range. However, because of the primary focus on the geographical position of a population, this framework provides little insight into the environmental factors regulating local abundance. While range-wide variation in population abundance associated with environmental conditions has been investigated in terrestrial species, the relationship between climate and local abundance in freshwater taxa across species' distributions is not well understood. We used GIS-based temperature and precipitation data to determine the relationships between climatic conditions and range-wide variation in local abundance for 19 species of North American freshwater fishes. Climate predicted a portion of the variation in local abundance among populations for 18 species. In addition, the relationship between climatic conditions and local abundance varied among species, which is expected as lineages partition the environment across geographical space. The influence of local habitat quality on species persistence is well documented; however, our results also indicate the importance of climate in regulating population sizes across a species geographical range, even in aquatic taxa.

  11. Abundant Semigroups with a Multiplicative Adequate Transversal

    Institute of Scientific and Technical Information of China (English)

    GUO Xiao Jiang

    2002-01-01

    The aim of this paper is to investigate abundant semigroups with a multiplicative adequate transversal. Some properties and characterizations for such semigroups are obtained. In particular,we establish the structure of this class of abundant semigroups in terms of left normal bands, right normal bands and adequate semigroups with some simple compatibility conditions. Finally, we apply this structure to some special cases.

  12. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter depositi

  13. Resource Abundance and Resource Dependence in China

    NARCIS (Netherlands)

    Ji, K.; Magnus, J.R.; Wang, W.

    2010-01-01

    This paper reconsiders the ‘curse of resources’ hypothesis for the case of China, and distinguishes between resource abundance, resource rents, and resource dependence. Resource abundance and resource rents are shown to be approximately equivalent, and their association with resource dependence vari

  14. On the Solar Nickel and Oxygen Abundances

    Science.gov (United States)

    Scott, Pat; Asplund, Martin; Grevesse, Nicolas; Sauval, A. Jacques

    2009-02-01

    Determinations of the solar oxygen content relying on the neutral forbidden transition at 630 nm depend upon the nickel abundance, due to a Ni I blend. Here, we rederive the solar nickel abundance, using the same ab initio three-dimensional hydrodynamic model of the solar photosphere employed in the recent revision of the abundances of C, N, O, and other elements. Using 17 weak, unblended lines of Ni I together with the most accurate atomic and observational data available, we find log epsilonNi = 6.17 ± 0.02(statistical) ± 0.05(systematic), a downward shift of 0.06-0.08 dex relative to previous abundances based on one-dimensional model atmospheres. We investigate the implications of the new nickel abundance for studies of the solar oxygen abundance based on the [O I] 630 nm line in the quiet Sun. Furthermore, we demonstrate that the oxygen abundance implied by the recent sunspot spectropolarimetric study of Centeno & Socas-Navarro needs to be revised downward from log epsilonO = 8.86 ± 0.07 to 8.71 ± 0.10. This revision is based on the new nickel abundance, the application of the best available gf value for the 630 nm forbidden oxygen line, and a more transparent treatment of CO formation. Determinations of the solar oxygen content relying on forbidden lines now appear to converge around log epsilonO = 8.7.

  15. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter depositi

  16. Evaluation of three high abundance protein depletion kits for umbilical cord serum proteomics

    Directory of Open Access Journals (Sweden)

    Nie Jing

    2011-05-01

    Full Text Available Abstract Background High abundance protein depletion is a major challenge in the study of serum/plasma proteomics. Prior to this study, most commercially available kits for depletion of highly abundant proteins had only been tested and evaluated in adult serum/plasma, while the depletion efficiency on umbilical cord serum/plasma had not been clarified. Structural differences between some adult and fetal proteins (such as albumin make it likely that depletion approaches for adult and umbilical cord serum/plasma will be variable. Therefore, the primary purposes of the present study are to investigate the efficiencies of several commonly-used commercial kits during high abundance protein depletion from umbilical cord serum and to determine which kit yields the most effective and reproducible results for further proteomics research on umbilical cord serum. Results The immunoaffinity based kits (PROTIA-Sigma and 5185-Agilent displayed higher depletion efficiency than the immobilized dye based kit (PROTBA-Sigma in umbilical cord serum samples. Both the PROTIA-Sigma and 5185-Agilent kit maintained high depletion efficiency when used three consecutive times. Depletion by the PROTIA-Sigma Kit improved 2DE gel quality by reducing smeared bands produced by the presence of high abundance proteins and increasing the intensity of other protein spots. During image analysis using the identical detection parameters, 411 ± 18 spots were detected in crude serum gels, while 757 ± 43 spots were detected in depleted serum gels. Eight spots unique to depleted serum gels were identified by MALDI- TOF/TOF MS, seven of which were low abundance proteins. Conclusions The immunoaffinity based kits exceeded the immobilized dye based kit in high abundance protein depletion of umbilical cord serum samples and dramatically improved 2DE gel quality for detection of trace biomarkers.

  17. Plasma Antenna

    OpenAIRE

    N M Vijay

    2014-01-01

    The fundamental base of plasma antenna is the use of an ionized medium as a conductor. The plasma antenna is a radiofrequency antenna formed by a plasma columns, Filaments or sheets, which are excited by a surface wave. The relevance of this device is how rapidly it can be turned on and off, only applying an electrical pulse. Besides its wide carrier frequency, the great directivity and controllable antenna shape. Otherwise a disadvantage is that it needs energy to be ionized....

  18. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  19. Bacterioplankton abundance and production and nanozooplankton abundance in Kenyan coastal waters (Western Indian Ocean)

    NARCIS (Netherlands)

    Goosen, N.K.; Van Rijswijk, P.; De Bie, M.J.M.; Peene, J.; Kromkamp, J.C.

    1997-01-01

    Bacterial abundance, [H-3]thymidine incorporation rate and heterotrophic nanoflagellate abundance were measured in the water column along transects perpendicular to the Kenyan coast (western Indian Ocean) during June-July (SE monsoon) and November-December (intermonsoon) 1992. Bacterial abundance wa

  20. Detecting Abundance Variations in Planetary Nebulae

    Science.gov (United States)

    Monteiro, H.; Santos, P. M.; Falceta-Gonçalves, D.

    2014-04-01

    Empirical methods of investigating chemical abundances are still widely used as a primary tool to study planetary nebulae (PNe) as well as HII regions. In this work we investigate the capacity of the empirical abundance determination methods to recover pre-defined parameters and abundance variations in a realistically modeled planetary nebula. To perform the test we use a threedimensional density structure obtained from a hydrodynamical simulation which is fed through a threedimensional photoionization code. The density structure is an asymetrical and inhomogeneous elongated closed shell. The input parameters used, such as, ionizing source, density, and chemical abundances are typical values of type I PNe. The model emissivities are then projected in the line of sight and emission line maps are generated, which are used to obtain the temperature and density diagnostics. The diagnostics and line emission maps are then used to obtain spatially resolved maps of the abundances. In this work we use the method described above to investigate abundances for two distinct orientations of the density structure. Our results show that for typical signal to noise ratios obtained from long-slit spectroscopy, only large abundance variations can be determined with good precision.

  1. Experimental and theoretical oscillator strengths of Mg I for accurate abundance analysis

    CERN Document Server

    Rhodin, A Pehlivan; Nilsson, H; Jonsson, P

    2016-01-01

    Context. With the aid of stellar abundance analysis, it is possible to study the galactic formation and evolution. Magnesium is an important element to trace the alpha-element evolution in our Galaxy. For chemical abundance analysis, such as magnesium abundance, accurate and complete atomic data are essential. Inaccurate atomic data lead to uncertain abundances and prevent discrimination between different evolution models. Aims. We study the spectrum of neutral magnesium from laboratory measurements and theoretical calculations. Our aim is to improve the oscillator strengths ( f -values) of Mg I lines and to create a complete set of accurate atomic data, particularly for the near-IR region. Methods. We derived oscillator strengths by combining the experimental branching fractions with radiative lifetimes reported in the literature and computed in this work. A hollow cathode discharge lamp was used to produce free atoms in the plasma and a Fourier transform spectrometer recorded the intensity-calibrated high-r...

  2. Imaging the elusive H-poor gas in planetary nebulae with large abundance discrepancy factors

    CERN Document Server

    García-Rojas, J; Boffin, H M J; Monteiro, H; Jones, D; Wesson, R; Cabrera-Lavers, A; Rodríguez-Gil, P

    2016-01-01

    The discrepancy between abundances computed using optical recombination lines (ORLs) and collisionally excited lines (CELs) is a major, unresolved problem with significant implications for the determination of chemical abundances throughout the Universe. In planetary nebulae (PNe), the most common explanation for the discrepancy is that two different gas phases coexist: a hot component with standard metallicity, and a much colder plasma enhanced in heavy elements. This dual nature is not predicted by mass loss theories, and direct observational support for it is still weak. In this work, we present our recent findings that demonstrate that the largest abundance discrepancies are associated with close binary central stars. OSIRIS-GTC tunable filter imaging of the faint O II ORLs and MUSE-VLT deep 2D spectrophotometry confirm that O II ORL emission is more centrally concentrated than that of [O III] CELs and, therefore, that the abundance discrepancy may be closely linked to binary evolution.

  3. Lithium Abundance of Metal-poor Stars

    Institute of Scientific and Technical Information of China (English)

    Hua-Wei Zhang; Gang Zhao

    2003-01-01

    High-resolution, high signal-to-noise ratio spectra have been obtained for 32 metal-poor stars. The equivalent widths of Li λ6708A were measured and the lithium abundances were derived. The average lithium abundance of 21 stars on the lithium plateau is 2.33±0.02 dex. The Lithium plateau exhibits a marginal trend along metallicity, dA(Li)/d[Fe/H] = 0.12±0.06, and no clear trend with the effective temperature. The trend indicates that the abundance of lithium plateau may not be primordial and that a part of the lithium was produced in Galactic Chemical Evolution (GCE).

  4. Study of the primordial lithium abundance

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Lithium isotopes have attracted an intense interest because the abundance of both 6Li and 6Li from big bang nucleosynthesis (BBN) is one of the puzzles in nuclear astrophysics. Many investigations of both astrophysical observation and nucleosynthesis calculation have been carried out to solve the puzzle, but it is not solved yet. Several nuclear reactions involving lithium have been indirectly measured at China Institute of Atomic Energy, Beijing. The Standard BBN (SBBN) network calculations are then performed to investigate the primordial Lithium abundance. The result shows that these nuclear reactions have minimal effect on the SBBN abundances of 6Li and 7Li.

  5. Plasma Extraction of Oxygen from Martian Atmosphere Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Plasma techniques are proposed for the extraction of oxygen from the abundant carbon dioxide contained in the Martian atmosphere (96 % CO2). In this process, CO2 is...

  6. Plasma Catalytic Extraction of Oxygen from the Martian Atmosphere Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Plasma catalytic techniques are proposed for the extraction of oxygen from the abundant carbon dioxide contained in the Martian atmosphere (95% CO2).. The Phase I...

  7. Estimating Squirrel Abundance From Live trapping Data

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A reprint of an article from the Journal of Wildlife Management entitled "Estimating Squirrel Abundance from Live Trapping Data" by Nixon, Edwards and Eberhardt. The...

  8. Chinook Abundance - Linear Features [ds181

    Data.gov (United States)

    California Department of Resources — The dataset 'ds181_Chinook_ln' is a product of the CalFish Adult Salmonid Abundance Database. Data in this shapefile are collected from stream sections or reaches...

  9. Iron abundance in the atmosphere of Arcturus

    CERN Document Server

    Sheminova, V A

    2015-01-01

    Abundance of iron in the atmosphere of Arcturus has been determined from the profiles or regions of the profiles of the weak lines sensitive to iron abundance. The selected lines of Fe I and Fe II were synthesized with the MARCS theoretical models of the atmosphere. From the observed profiles of lines available with a high spectral resolution in the atlas by Hinkle and Wallace (2005), the values of the iron abundance $A = 6.95 \\pm 0.03$ and the radial-tangential macroturbulent velocity $5.6 \\pm 0.2$ km/s were obtained for Arcturus. The same physical quantities were found for the Sun as a star; they are $7.42 \\pm 0.02$ and $3.4 \\pm 0.3$ km/s, respectively. For Arcturus, the iron abundance relative to the solar one was determined with the differential method as [Fe/H] $=-0.48 \\pm 0.02$.

  10. Chemical abundance analysis of 19 barium stars

    CERN Document Server

    Yang, G C; Spite, M; Chen, Y Q; Zhao, G; Zhang, B; Liu, G Q; Liu, Y J; Liu, N; Deng, L C; Spite, F; Hill, V; Zhang, C X

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures, surface gravities, metallicity and microturbulent velocity) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their light elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn and Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-ca...

  11. SWFSC/MMTD: Vaquita Abundance Survey 1997

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1997, the Southwest Fisheries Science Center (SWFSC) conducted a survey designed to estimate the abundance of vaquita, the Gulf of California harbor porpoise...

  12. Does land abundance explain African institutions?

    OpenAIRE

    2012-01-01

    The land abundance view of African history uses sparse population to explain pre-colonial land tenure and slavery. I document the geographic forcing variables that predict land rights, slavery, and population density in a cross section of global societies. I discuss whether these correlations support theories of land rights and slavery, including the land abundance view. I show that pre-colonial institutions predict institutional outcomes in Africa in the present, including land transactions,...

  13. Modelling Void Abundance in Modified Gravity

    CERN Document Server

    Voivodic, Rodrigo; Llinares, Claudio; Mota, David F

    2016-01-01

    We use a spherical model and an extended excursion set formalism with drifting diffusive barriers to predict the abundance of cosmic voids in the context of general relativity as well as f(R) and symmetron models of modified gravity. We detect spherical voids from a suite of N-body simulations of these gravity theories and compare the measured void abundance to theory predictions. We find that our model correctly describes the abundance of both dark matter and galaxy voids, providing a better fit than previous proposals in the literature based on static barriers. We use the simulation abundance results to fit for the abundance model free parameters as a function of modified gravity parameters, and show that counts of dark matter voids can provide interesting constraints on modified gravity. For galaxy voids, more closely related to optical observations, we find that constraining modified gravity from void abundance alone may be significantly more challenging. In the context of current and upcoming galaxy surv...

  14. Planetary nebulae abundances and stellar evolution

    CERN Document Server

    Pottasch, S R

    2006-01-01

    A summary is given of planetary nebulae abundances from ISO measurements. It is shown that these nebulae show abundance gradients (with galactocentric distance), which in the case of neon, argon, sulfur and oxygen (with four exceptions) are the same as HII regions and early type star abundance gradients. The abundance of these elements predicted from these gradients at the distance of the Sun from the center are exactly the solar abundance. Sulfur is the exception to this; the reason for this is discussed. The higher solar neon abundance is confirmed; this is discussed in terms of the results of helioseismology. Evidence is presented for oxygen destruction via ON cycling having occurred in the progenitors of four planetary nebulae with bilobal structure. These progenitor stars had a high mass, probably greater than 5 solar masses. This is deduced from the high values of He/H and N/H found in these nebulae. Formation of nitrogen, helium and carbon are discussed. The high mass progenitors which showed oxygen de...

  15. TEA: A Code Calculating Thermochemical Equilibrium Abundances

    Science.gov (United States)

    Blecic, Jasmina; Harrington, Joseph; Bowman, M. Oliver

    2016-07-01

    We present an open-source Thermochemical Equilibrium Abundances (TEA) code that calculates the abundances of gaseous molecular species. The code is based on the methodology of White et al. and Eriksson. It applies Gibbs free-energy minimization using an iterative, Lagrangian optimization scheme. Given elemental abundances, TEA calculates molecular abundances for a particular temperature and pressure or a list of temperature-pressure pairs. We tested the code against the method of Burrows & Sharp, the free thermochemical equilibrium code Chemical Equilibrium with Applications (CEA), and the example given by Burrows & Sharp. Using their thermodynamic data, TEA reproduces their final abundances, but with higher precision. We also applied the TEA abundance calculations to models of several hot-Jupiter exoplanets, producing expected results. TEA is written in Python in a modular format. There is a start guide, a user manual, and a code document in addition to this theory paper. TEA is available under a reproducible-research, open-source license via https://github.com/dzesmin/TEA.

  16. Plasma Physics and Controlled Nuclear Fusion

    Science.gov (United States)

    Fisch, N. J.

    2010-01-01

    Already while making his famous contributions in uncontrolled nuclear fusion for wartime uses, Edward Teller contemplated how the abundant energy release through nuclear fusion might serve peacetime uses as well. His legacy in controlled nuclear fusion, and the associated physics of plasmas, spans both magnetic and inertial confinement approaches. His contributions in plasma physics, both the intellectual and the administrative, continue to impact the field.

  17. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  18. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  19. Solar abundances with the SPICE spectral imager on Solar Orbiter

    Science.gov (United States)

    Giunta, Alessandra; Haberreiter, Margit; Peter, Hardi; Vial, Jean-Claude; Harrison, Richard; Parenti, Susanna; Innes, Davina; Schmutz, Werner; Buchlin, Eric; Chamberlin, Phillip; Thompson, William; Bocchialini, Karine; Gabriel, Alan; Morris, Nigel; Caldwell, Martin; Auchere, Frederic; Curdt, Werner; Teriaca, Luca; Hassler, Donald M.; DeForest, Craig; Hansteen, Viggo; Carlsson, Mats; Philippon, Anne; Janvier, Miho; Wimmer-Schweingruber, Robert; Griffin, Douglas; Baudin, Frederic; Davila, Joseph; Fludra, Andrzej; Waltham, Nick; Eccleston, Paul; Gottwald, Alexander; Klein, Roman; Hanley, John; Walls, Buddy; Howe, Chris; Schuehle, Udo; Gyo, Manfred; Pfiffner, Dany

    2016-07-01

    Elemental composition of the solar atmosphere and in particular abundance bias of low and high First Ionization Potential (FIP) elements are a key tracer of the source regions of the solar wind. These abundances and their spatio-temporal variations, as well as the other plasma parameters , will be derived by the SPICE (Spectral Imaging of the Coronal Environment) EUV spectral imager on the upcoming Solar Orbiter mission. SPICE is designed to provide spectroheliograms (spectral images) using a core set of emission lines arising from ions of both low-FIP and high-FIP elements. These lines are formed over a wide range of temperatures, enabling the analysis of the different layers of the solar atmosphere. SPICE will use these spectroheliograms to produce dynamic composition maps of the solar atmosphere to be compared to in-situ measurements of the solar wind composition of the same elements (i.e. O, Ne, Mg, Fe). This will provide a tool to study the connectivity between the spacecraft (the Heliosphere) and the Sun. We will discuss the SPICE capabilities for such composition measurements.

  20. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  1. Abundance, distribution and patch formation of zooplankton

    Science.gov (United States)

    Paffenhöfer, Gustav-Adolf; Sherman, Byron K.; Lee, Thomas N.

    The goal of studies described here was to determine the responses of zooplankton taxa to phytoplankton patches which develop in and near intrusions of cold, nutrient-rich Gulf Stream water. To achieve this goal we determined the horizontal and vertical distributions of abundant mesozooplankton taxa on the south-eastern continental shelf of the USA between 29°30‧ and 31°N. The study period was from June 23 to August 16, 1981. Highest concentrations of zooplankton usually occurred in and near patches of phytoplankton. Increased phytoplankton appeared to trigger the formation of patches of the calanoid copepod Temora turbinata and the cyclopoid copepods Oithona spp. and Oncaea spp. The patches of zooplankton had greater alongshore than cross-shelf dimensions. T. turbinata responded rapidly to increased concentrations of phytoplankton by reproducing and aggregating in and above intruded waters. Oithonidae which were often, but not always, abundant in phytoplankton patches eventually attained high concentrations over most of the middle and part of the inner shelf. Their concentration and that of Oncaeidae increased steadily. Oncaeidae were not abundant in recently upwelled waters, as was T. turbinata but reached high concentrations in older intrusions when the abundance of T. turbinata remained level or decreased slowly. Both cyclopoid taxa are thought to reproduce slowly (egg sacs) compared to T. turbinata. Another taxon, the doliolids, became abundant far more rapidly in intruded waters (by asexual reproduction) than did the other three taxa. Doliolids were the most opportunistic intrusion zooplankton form. They do not regularly occur in low abundance on the shelf, as do the three copepod taxa, but develop in pulses in regions where T. turbinata and Oncaea are not abundant. Of the four taxa studied the abundance of doliolids increased and decreased most rapidly, whereas Oithona and Oncaea increased slowly and did not decrease during the study period. T. turbinata

  2. Abundance differences among G and K giants

    Science.gov (United States)

    Challener, Sharon Lynn Montgomery

    Effective temperatures and surface gravities were derived for 52 G and K giants using model atmosphere. Of these, 33 were called very strong-lined (or VSL) stars primarily because of their CN line strength. We find that when compared to normal stars, the VSL stars show a mean iron overabundance of 0.15 dex. Contrary to earlier suggestions, none of the heavier elements (Z greater than 10) appear selectively enhanced. Red giants are believed to undergo mixing, thereby driving the surface abundances towards those of the stellar interior. Carbon, nitrogen, and oxygen abundances are most sensitive to mixing as they are produced through nucleosynthesis at various depths beneath the star's surface. The CNO abundances (normalized to the iron abundances) of the VSLs appear on average to be normal for G and K giants. This result suggests that the strong CN absorption seen in VSLs is not the result of unusual mixing. Their general overabundance of metal appears instead to be innate, presumably reflecting the metallicity of the gaseous clouds from which they formed. This should be settled once the appropriate number of VSL dwarfs is found. The deviations from the normal population of giants are rather small, however, and certainly not of the magnitude envisioned by Spinrad and Taylor (1969). It is likely that VSLs are merely the stars lying in the tail of the normal abundance distribution.

  3. Oxygen abundance maps of CALIFA galaxies

    CERN Document Server

    Zinchenko, I A; Grebel, E K; Sanchez, S F; Vilchez, J M

    2016-01-01

    We construct maps of the oxygen abundance distribution across the disks of 88 galaxies using CALIFA data release 2 (DR2) spectra. The position of the center of a galaxy (coordinates on the plate) were also taken from the CALIFA DR2. The galaxy inclination, the position angle of the major axis, and the optical radius were determined from the analysis of the surface brightnesses in the SDSS $g$ and $r$ bands of the photometric maps of SDSS data release 9. We explore the global azimuthal abundance asymmetry in the disks of the CALIFA galaxies and the presence of a break in the radial oxygen abundance distribution. We found that there is no significant global azimuthal asymmetry for our sample of galaxies, i.e., the asymmetry is small, usually lower than 0.05 dex. The scatter in oxygen abundances around the abundance gradient has a comparable value, $\\lesssim 0.05$ dex. A significant (possibly dominant) fraction of the asymmetry can be attributed to the uncertainties in the geometrical parameters of these galaxie...

  4. The iron abundance of the Magellanic Bridge

    CERN Document Server

    Dufton, P L; Thompson, H M A; Street, R A

    2008-01-01

    High-resolution HST ultra-violet spectra for five B-type stars in the Magellanic Bridge and in the Large and Small Magellanic Clouds have been analysed to estimate their iron abundances. Those for the Clouds are lower than estimates obtained from late-type stars or the optical lines in B-type stars by approximately 0.5 dex. This may be due to systematic errors possibly arising from non-LTE effects or from errors in the atomic data as similar low Fe abundances having previously been reported from the analysis of the ultra-violet spectra of Galactic early-type stars. The iron abundance estimates for all three Bridge targets appear to be significantly lower than those found for the SMC and LMC by approximately -0.5 dex and -0.8 dex respectively and these differential results should not be affected by any systematic errors present in the absolute abundance estimates. These differential iron abundance estimates are consistent with the underabundances for C, N, O, Mg and Si of approximately -1.1 dex relative to our...

  5. The Iron abundance in Galactic Planetary Nebulae

    CERN Document Server

    Delgado-Inglada, G; Mampaso, A; Viironen, K

    2008-01-01

    We constrain the iron abundance in a sample of 33 low-ionization Galactic planetary nebulae (PNe) using [Fe III] lines and correcting for the contribution of higher ionization states with ionization correction factors (ICFs) that take into account uncertainties in the atomic data. We find very low iron abundances in all the objects, suggesting that more than 90% of their iron atoms are condensed onto dust grains. This number is based on the solar iron abundance and implies a lower limit on the dust-to-gas mass ratio, due solely to iron, of M_dust/M_gas>1.3x10^{-3} for our sample. The depletion factors of different PNe cover about two orders of magnitude, probably reflecting differences in the formation, growth, or destruction of their dust grains. However, we do not find any systematic difference between the gaseous iron abundances calculated for C-rich and O-rich PNe, suggesting similar iron depletion efficiencies in both environments. The iron abundances of our sample PNe are similar to those derived follow...

  6. Abundance of sea kraits correlates with precipitation.

    Science.gov (United States)

    Lillywhite, Harvey B; Tu, Ming-Chung

    2011-01-01

    Recent studies have shown that sea kraits (Laticauda spp.)--amphibious sea snakes--dehydrate without a source of fresh water, drink only fresh water or very dilute brackish water, and have a spatial distribution of abundance that correlates with freshwater sites in Taiwan. The spatial distribution correlates with sites where there is a source of fresh water in addition to local precipitation. Here we report six years of longitudinal data on the abundance of sea kraits related to precipitation at sites where these snakes are normally abundant in the coastal waters of Lanyu (Orchid Island), Taiwan. The number of observed sea kraits varies from year-to-year and correlates positively with previous 6-mo cumulative rainfall, which serves as an inverse index of drought. Grouped data for snake counts indicate that mean abundance in wet years is nearly 3-fold greater than in dry years, and this difference is significant. These data corroborate previous findings and suggest that freshwater dependence influences the abundance or activity of sea kraits on both spatial and temporal scales. The increasing evidence for freshwater dependence in these and other marine species have important implications for the possible impact of climate change on sea snake distributions.

  7. Abundance of sea kraits correlates with precipitation.

    Directory of Open Access Journals (Sweden)

    Harvey B Lillywhite

    Full Text Available Recent studies have shown that sea kraits (Laticauda spp.--amphibious sea snakes--dehydrate without a source of fresh water, drink only fresh water or very dilute brackish water, and have a spatial distribution of abundance that correlates with freshwater sites in Taiwan. The spatial distribution correlates with sites where there is a source of fresh water in addition to local precipitation. Here we report six years of longitudinal data on the abundance of sea kraits related to precipitation at sites where these snakes are normally abundant in the coastal waters of Lanyu (Orchid Island, Taiwan. The number of observed sea kraits varies from year-to-year and correlates positively with previous 6-mo cumulative rainfall, which serves as an inverse index of drought. Grouped data for snake counts indicate that mean abundance in wet years is nearly 3-fold greater than in dry years, and this difference is significant. These data corroborate previous findings and suggest that freshwater dependence influences the abundance or activity of sea kraits on both spatial and temporal scales. The increasing evidence for freshwater dependence in these and other marine species have important implications for the possible impact of climate change on sea snake distributions.

  8. The solar photospheric abundance of zirconium

    CERN Document Server

    Caffau, Elisabetta; Ludwig, Hans-Günter; Bonifacio, Piercarlo; Steffen, Matthias

    2010-01-01

    Zirconium (Zr), together with strontium and yttrium, is an important element in the understanding of the Galactic nucleosynthesis. In fact, the triad Sr-Y-Zr constitutes the first peak of s-process elements. Despite its general relevance not many studies of the solar abundance of Zr were conducted. We derive the zirconium abundance in the solar photosphere with the same CO5BOLD hydrodynamical model of the solar atmosphere that we previously used to investigate the abundances of C-N-O. We review the zirconium lines available in the observed solar spectra and select a sample of lines to determine the zirconium abundance, considering lines of neutral and singly ionised zirconium. We apply different line profile fitting strategies for a reliable analysis of Zr lines that are blended by lines of other elements. The abundance obtained from lines of neutral zirconium is very uncertain because these lines are commonly blended and weak in the solar spectrum. However, we believe that some lines of ionised zirconium are...

  9. Estimating the relationship between abundance and distribution

    DEFF Research Database (Denmark)

    Rindorf, Anna; Lewy, Peter

    2012-01-01

    Numerous studies investigate the relationship between abundance and distribution using indices reflecting one of the three aspects of distribution: proportion of area occupied, aggregation, and geographical range. Using simulations and analytical derivations, we examine whether these indices...... based on Euclidean distance to the centre of gravity of the spatial distribution. Only the proportion of structurally empty areas, Lloyds index, and indices of the distance to the centre of gravity of the spatial distribution are unbiased at all levels of abundance. The remaining indices generate...... relationships between abundance and distribution even in cases where no underlying relationships exists, although the problem decreases for measures derived from Lorenz curves when samples contain more than four individuals on average. To illustrate the problem, the indices are applied to juvenile North Sea cod...

  10. Planetary Nebula Abundances and Morphology: Probing the Chemical Evolution of the Milky Way

    CERN Document Server

    Stanghellini, L; Cunha, K; Manchado, A; Villaver, E

    2006-01-01

    This paper presents a homogeneous study of abundances in a sample of 79 northern galactic planetary nebulae whose morphological classes have been uniformly determined. Ionic abundances and plasma diagnostics were derived from selected optical line strengths in the literature, and elemental abundances were estimated with the Ionization Correction Factor developed by Kingsbourgh & Barlow (1994). We compare the elemental abundances to the final yields obtained from stellar evolution models of low-and intermediate-mass stars, and we confirm that most Bipolar planetary nebulae have high nitrogen and helium abundance, and are the likely progeny of stars with main-sequence mass larger than 3 solar masses. We derive =0.27, and discuss the implication of such a high ratio in connection with the solar neon abundance. We determine the galactic gradients of oxygen and neon, and found Delta log (O/H)/Delta R=-0.01 dex/kpc$ and Delta log (Ne/H)/Delta R=-0.01 dex/kpc. These flat PN gradients do not reconcile with galact...

  11. plasma treatment

    Directory of Open Access Journals (Sweden)

    Puač Nevena

    2014-11-01

    Full Text Available In this paper we will present results for plasma sterilization of planktonic samples of two reference strains of bacteria, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. We have used a plasma needle as a source of non-equilibrium atmospheric plasma in all treatments. This device is already well characterized by OES, derivative probes and mass spectrometry. It was shown that power delivered to the plasma is bellow 2 W and that it produces the main radical oxygen and nitrogen species believed to be responsible for the sterilization process. Here we will only present results obtained by electron paramagnetic resonance which was used to detect the OH, H and NO species. Treatment time and power delivered to the plasma were found to have the strongest influence on sterilization. In all cases we have observed a reduction of several orders of magnitude in the concentration of bacteria and for the longest treatment time complete eradication. A more efficient sterilization was achieved in the case of gram negative bacteria.

  12. Plasma metallization

    CERN Document Server

    Crowther, J M

    1997-01-01

    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  13. Plasma dynamo

    CERN Document Server

    Rincon, F; Schekochihin, A A; Valentini, F

    2015-01-01

    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  14. Monster Sawtooth Activity in Ohmically Heated HT-7 Plasma

    Institute of Scientific and Technical Information of China (English)

    胡立群; 石跃江; 刘胜侠

    2001-01-01

    Experimental properties of monster sawtooth activities in ohmic HT-7 plasma are presented in this paper. The monster sawtooth activities belong to global fluctuations and are characterized with a series of large core collapses on SXR intensity traces with a long period, a large amplitude fluctuation and a large inversion radius. However, they emerge without apparent deterioration of plasma confinement and without major plasma disruption. During the events,long partial sawtooth collapses and abundant MHD phenomena are also observed.

  15. Analysis of 26 Barium Stars I. Abundances

    CERN Document Server

    Allen, D M; Allen, Dinah M.; Barbuy, Beatriz

    2006-01-01

    We present a detailed analysis of 26 barium stars, including dwarf barium stars, providing their atmospheric parameters (Teff, log g, [Fe/H], vt) and elemental abundances. We aim at deriving gravities and luminosity classes of the sample stars, in particular to confirm the existence of dwarf barium stars. Accurate abundances of chemical elements were derived. Abundance ratios between nucleosynthetic processes, by using Eu and Ba as representatives of the r- and s-processes are presented. High-resolution spectra with the FEROS spectrograph at the ESO-1.5m Telescope, and photometric data with Fotrap at the Zeiss telescope at the LNA were obtained. The atmospheric parameters were derived in an iterative way, with temperatures obtained from colour-temperature calibrations. The abundances were derived using spectrum synthesis for Li, Na, Al, alpha-, iron peak, s- and r-elements atomic lines, and C and N molecular lines. Atmospheric parameters in the range 4300 < Teff < 6500, -1.2 < [Fe/H] < 0.0 and 1.4...

  16. Simulation of arthropod abundance from plant composition

    Directory of Open Access Journals (Sweden)

    WenJun Zhang

    2011-04-01

    Full Text Available The relationship between arthropod abundance and plant composition is extremely complex. It is very hard to develop a mechanistic model to describe the relationship. This study aimed to simulate arthropod abundance from plant composition on grassland using an artificial neural network developed by the author, and to compare simulation performances between the neural network and conventional models. The results revealed that there were complex interactions between plants and arthropods, and the arthropod abundance on grassland was significantly determined of plant families and their cover-degrees rather than plant species and their cover-degrees. Neural network exhibited a better simulation performance than multivariate regression and response surface model. Cross validation indicated that prediction performance of neural network was also superior to these models. It was concluded that neural network is an effective tool to model arthropod abundance from plant composition on grassland. A moderate dimensionality for input space may be determined to produce a reasonably trained neural network. Such procedures for dimensionality reduction as PCE, etc., were suggested being used in the data treatment in neural network modeling. A high dimensionality for input space and a few samples in the input set would result in the deficient learning of neural network. Randomization procedure for sample submission would help to eliminate the sequence correlation but may result in a worse performance in simulation and prediction. It was suggested that randomization procedure could be used to the sample submission for these situations with a lot of samples and a lower dimensionality.

  17. Zooplankton abundance of the Andaman sea

    Digital Repository Service at National Institute of Oceanography (India)

    Madhupratap, M.; Achuthankutty, C.T.; Nair, S.R.S.; Nair, V.R.

    Zooplankton biomass and abundance of major groups from the Andaman Sea in February 1979 are presented. Average zooplankton biomass is 5.6 ml/100 m3 and is generally poor compared to reported values from east and west coasts of India. Copepoda forms...

  18. Securing abundance : The politics of energy security

    NARCIS (Netherlands)

    Kester, Johannes

    2016-01-01

    Energy Security is a concept that is known in the literature for its ‘slippery’ nature and subsequent wide range of definitions. Instead of another attempt at grasping the essence of this concept, Securing Abundance reformulates the problem and moves away from a definitional problem to a theoretical

  19. In Abundance: Networked Participatory Practices as Scholarship

    Science.gov (United States)

    Stewart, Bonnie E.

    2015-01-01

    In an era of knowledge abundance, scholars have the capacity to distribute and share ideas and artifacts via digital networks, yet networked scholarship often remains unrecognized within institutional spheres of influence. Using ethnographic methods including participant observation, interviews, and document analysis, this study investigates…

  20. North Sea Elasmobranchs: distribution, abundance and biodiversity

    NARCIS (Netherlands)

    Daan, N.; Heessen, H.J.L.; Hofstede, ter R.

    2005-01-01

    Based on data from various international and national surveys, an overview is given of the fine-scale distribution (resolution of 20¿longitude * 10¿ latitude; ¿ 10*10 nm) and trends in abundance of elasmobranch species reported from the North Sea. Presence-absence maps are produced based on 4

  1. Abundances of planetary nebula NGC2392

    NARCIS (Netherlands)

    Pottasch, S. R.; Bernard-Salas, J.; Roellig, T. L.

    The spectra of the planetary nebula NGC2392 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope. The aim is to determine the chemical composition of this object. We also make use of IUE and ground based spectra. Abundances determined from the

  2. Solar neon abundances from gamma-ray spectroscopy and He-3-rich particle events

    Science.gov (United States)

    Reames, D. V.; Ramaty, R.; Von Rosenvinge, T. T.

    1988-01-01

    Ambient solar atmospheric abundances derived from gamma-ray spectroscopy are compared with observations of solar energetic particles. Agreement is found between the gamma-ray-derived Ne/O ratio and the corresponding mean ratio for He-3-rich flares. Both of these values are significantly higher than inferred coronal Ne/O ratios. It is suggested that the mean Ne/O ratio in He-3-rich flares reflects the composition of the flare plasma rather than the acceleration process.

  3. Toward reliable estimates of abundance: comparing index methods to assess the abundance of a Mammalian predator.

    Directory of Open Access Journals (Sweden)

    Denise Güthlin

    Full Text Available Due to time and financial constraints indices are often used to obtain landscape-scale estimates of relative species abundance. Using two different field methods and comparing the results can help to detect possible bias or a non monotonic relationship between the index and the true abundance, providing more reliable results. We used data obtained from camera traps and feces counts to independently estimate relative abundance of red foxes in the Black Forest, a forested landscape in southern Germany. Applying negative binomial regression models, we identified landscape parameters that influence red fox abundance, which we then used to predict relative red fox abundance. We compared the estimated regression coefficients of the landscape parameters and the predicted abundance of the two methods. Further, we compared the costs and the precision of the two field methods. The predicted relative abundances were similar between the two methods, suggesting that the two indices were closely related to the true abundance of red foxes. For both methods, landscape diversity and edge density best described differences in the indices and had positive estimated effects on the relative fox abundance. In our study the costs of each method were of similar magnitude, but the sample size obtained from the feces counts (262 transects was larger than the camera trap sample size (88 camera locations. The precision of the camera traps was lower than the precision of the feces counts. The approach we applied can be used as a framework to compare and combine the results of two or more different field methods to estimate abundance and by this enhance the reliability of the result.

  4. Non-Salmonid Abundance - Line Features [ds186

    Data.gov (United States)

    California Department of Resources — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. The "Other Fish" category contains data collected...

  5. Plasma medicine

    CERN Document Server

    Fridman, Alexander

    2012-01-01

    This comprehensive text is suitable for researchers and graduate students of a 'hot' new topic in medical physics. Written by the world's leading experts,  this book aims to present recent developments in plasma medicine, both technological and scientific, reviewed in a fashion accessible to the highly interdisciplinary audience consisting of doctors, physicists, biologists, chemists and other scientists, university students and professors, engineers and medical practitioners. The book focuses on major topics and covers the physics required to develop novel plasma discharges relevant for medic

  6. Plasma physics and engineering

    CERN Document Server

    Fridman, Alexander

    2011-01-01

    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  7. Chemical Cartography in the Milky Way with SDSS/APOGEE: Multi-element abundances and abundance ratio variations

    Science.gov (United States)

    Holtzman, Jon A.; Hasselquist, Sten; Johnson, Jennifer; Bird, Jonathan C.; Majewski, Steven R.; SDSS/APOGEE Team

    2017-01-01

    The SDSS/APOGEE project is measuring abundances of multiple elements for several hundred thousand stars across the Milky Way. These allow the mapping of abundances and abundance ratio variations. Results will be presented for multiple abundance ratios across of the Galactic disk. The interpretation of mean abundance maps is complicated by variations in star formation history across the disk and by changing abundance ratios that result from an overall metallicity gradient. Variations in chemical abundance sequences, however, show the potential for using abundance ratios to track the movement of stars through the disk, and provide key information for constraining Galaxy formation and chemical evolution models.

  8. Ectopic Germinal Centers and IgG4-Producing Plasmacytes Observed in Synovia of HLA-B27+ Ankylosing Spondylitis Patients with Advanced Hip Involvement

    Directory of Open Access Journals (Sweden)

    Xiugao Feng

    2015-01-01

    Full Text Available Introduction. Ectopic lymphoid neogenesis and the presence of IgG4-positive plasmacytes have been confirmed in chronic inflammatory sclerosing diseases. This study aims to investigate hip synovial tissues of ankylosing spondylitis (AS patients for IgG4-positive plasma cells and ectopic lymphoid tissues with germinal centers (GCs. Methods. Synovial samples were collected from 7 AS patients who received total hip replacement and were evaluated using immunohistochemistry for the presence of CD20+ B-cells, CD3+ T-cells, CD21+ follicular dendritic cells (FDC, and CD38+ plasma cells. Furthermore, immunoglobulin G (IgG and IgG4, IgA, IgM, and complement components C3d and C4d in synovia were evaluated. Both synovial CD21+ FDCs and IgG4-producing plasmacytes were analyzed. Results. All seven patients had severe fibrosis. Massive infiltrations of lymphocytes were found in 5 out of 7 patients’ synovia. Ectopic lymphoid tissues with CD21+ FDC networks and IgG4-positive plasma cells were observed coincidentally in two patients’ synovia. Conclusion. The pathophysiological mechanism of AS patients’ hip damage might be related to the coincidental presence of ectopic lymphoid tissue with FDCs network and IgG4-positive plasma cells identified here for the first time in AS patients’ inflamed synovial tissue.

  9. The primordial helium abundance from updated emissivities

    CERN Document Server

    Aver, Erik; Porter, R L; Skillman, Evan D

    2013-01-01

    Observations of metal-poor extragalactic H II regions allow the determination of the primordial helium abundance, Y_p. The He I emissivities are the foundation of the model of the H II region's emission. Porter, Ferland, Storey, & Detisch (2012) have recently published updated He I emissivities based on improved photoionization cross-sections. We incorporate these new atomic data and update our recent Markov Chain Monte Carlo analysis of the dataset published by Izotov, Thuan, & Stasinska (2007). As before, cuts are made to promote quality and reliability, and only solutions which fit the data within 95% confidence level are used to determine the primordial He abundance. The previously qualifying dataset is almost entirely retained and with strong concordance between the physical parameters. Overall, an upward bias from the new emissivities leads to a decrease in Y_p. In addition, we find a general trend to larger uncertainties in individual objects (due to changes in the emissivities) and an increase...

  10. Earth Abundant Element Type I Clathrate Phases

    Directory of Open Access Journals (Sweden)

    Susan M. Kauzlarich

    2016-08-01

    Full Text Available Earth abundant element clathrate phases are of interest for a number of applications ranging from photovoltaics to thermoelectrics. Silicon-containing type I clathrate is a framework structure with the stoichiometry A8-xSi46 (A = guest atom such as alkali metal that can be tuned by alloying and doping with other elements. The type I clathrate framework can be described as being composed of two types of polyhedral cages made up of tetrahedrally coordinated Si: pentagonal dodecahedra with 20 atoms and tetrakaidecahedra with 24 atoms in the ratio of 2:6. The cation sites, A, are found in the center of each polyhedral cage. This review focuses on the newest discoveries in the group 13-silicon type I clathrate family: A8E8Si38 (A = alkali metal; E = Al, Ga and their properties. Possible approaches to new phases based on earth abundant elements and their potential applications will be discussed.

  11. The primordial deuterium abundance problems and prospects

    CERN Document Server

    Levshakov, S A; Kegel, W H; Levshakov, Sergei A.; Takahara, Fumio; Kegel, Wilhelm H.

    1997-01-01

    The current status of extragalactic deuterium abundance is discussed using two examples of `low' and `high' D/H measurements. We show that the discordance of these two types of D abundances may be a consequence of the spatial correlations in the stochastic velocity field. Within the framework of the generalized procedure (accounting for such effects) one finds good agreement between different observations and the theoretical predictions for standard big bang nucleosynthesis (SBBN). In particular, we show that the deuterium absorption seen at z = 2.504 toward Q1009+2956 and the H+D Ly-alpha profile observed at z = 0.701 toward Q1718+4807 are compatible with D/H $\\sim 4.1 - 4.6\\times10^{-5}$. This result supports SBBN and, thus, no inhomogeneity is needed. The problem of precise D/H measurements is discussed.

  12. A biogeographical perspective on species abundance distributions

    DEFF Research Database (Denmark)

    Matthews, Thomas J.; Borges, Paulo A. V.; de Azevedo, Eduardo Brito

    2017-01-01

    It has become increasingly recognized that multiple processes can generate similar shapes of species abundance distributions (SADs), with the result that the fit of a given SAD model cannot unambiguously provide evidence in support of a given theory or model. An alternative approach to comparing...... the fit of different SAD models to data from a single site is to collect abundance data from a variety of sites, and then build models to analyse how different SAD properties (e.g. form, skewness) vary with different predictor variables. Such a biogeographical approach to SAD research is potentially very...... revealing, yet there has been a general lack of interest in SADs in the biogeographical literature. In this Perspective, we address this issue by highlighting findings of recent analyses of SADs that we consider to be of intrinsic biogeographical interest. We use arthropod data drawn from the Azorean...

  13. Integral Field Spectroscopy Surveys: Oxygen Abundance Gradients

    Science.gov (United States)

    Sánchez, S. F.; Sánchez-Menguiano, L.

    2017-07-01

    We present here the recent results on our understanding of oxygen abundance gradients derived using Integral Field Spectroscopic surveys. In particular we analyzed more than 2124 datacubes corresponding to individual objects observed by the CALIFA (˜ 734 objects) and the public data by MaNGA (˜ 1390 objects), deriving the oxygen abundance gradient for each galaxy. We confirm previous results that indicate that the shape of this gradient is very similar for all galaxies with masses above 109.5M⊙, presenting in average a very similar slope of ˜ -0.04 dex within 0.5-2.0 re, with a possible drop in the inner regions (r109.5M⊙) the gradient seems to be flatter than for more massive ones. All these results agree with an inside-out growth of massive galaxies and indicate that low mass ones may still be growing in an outside in phase.

  14. In Abundance: Networked Participatory Practices as Scholarship

    Directory of Open Access Journals (Sweden)

    Bonnie E Stewart

    2015-06-01

    Full Text Available In an era of knowledge abundance, scholars have the capacity to distribute and share ideas and artifacts via digital networks, yet networked scholarship often remains unrecognized within institutional spheres of influence. Using ethnographic methods including participant observation, interviews, and document analysis, this study investigates networks as sites of scholarship. Its purpose is to situate networked practices within Boyer’s (1990 four components of scholarship – discovery, integration, application, and teaching – and to explore them as a techno-cultural system of scholarship suited to an era of knowledge abundance. Not only does the paper find that networked engagement both aligns with and exceeds Boyer’s model for scholarship, it suggests that networked scholarship may enact Boyer’s initial aim of broadening scholarship itself through fostering extensive cross-disciplinary, public ties and rewarding connection, collaboration, and curation between individuals rather than roles or institutions.

  15. Experimental Limit to Interstellar 244Pu Abundance

    CERN Document Server

    Paul, M; Ahmad, I; Berkovits, D; Bordeanu, C; Ghelberg, S; Hashimoto, Y; Hershcovitch, A I; Jiang, S; Nakanishi, T; Sakamoto, K

    2001-01-01

    Short-lived nuclides, now extinct in the solar system, are expected to be present in the interstellar medium (ISM). Grains of ISM origin were recently discovered in the inner solar system and at Earth orbit and may accrete onto Earth after ablation in the atmosphere. A favorable matrix for detection of such extraterrestrial material is presented by deep open-sea sediments with very low sedimentation rates (0.8-3 mm/kyr). We report here on the measurement of Pu isotopic abundances in a 1-kg deep-sea dry sediment collected in 1992 in the North Pacific. Our measured value of (3+-3)x10^5 244Pu atoms in the Pu-separated fraction of the sample shows no excess over the expected stratospheric nuclear fallout content and under reasonable assumptions we derive a limit of 2x10^-11 g-244Pu/g-ISM for the abundance of 244Pu in ISM.

  16. Estimating the relationship between abundance and distribution

    DEFF Research Database (Denmark)

    Rindorf, Anna; Lewy, Peter

    2012-01-01

    provide unbiased estimates of the relationship when estimated from count data. The indices investigated include the proportion of empty samples, the proportion of structurally empty samples, Lloyds index of patchiness, measures derived from Lorenz curves (such as D95 and the Gini index), and measures......Numerous studies investigate the relationship between abundance and distribution using indices reflecting one of the three aspects of distribution: proportion of area occupied, aggregation, and geographical range. Using simulations and analytical derivations, we examine whether these indices...... based on Euclidean distance to the centre of gravity of the spatial distribution. Only the proportion of structurally empty areas, Lloyds index, and indices of the distance to the centre of gravity of the spatial distribution are unbiased at all levels of abundance. The remaining indices generate...

  17. Detailed Chemical Abundances of Extragalactic Globular Clusters

    CERN Document Server

    Bernstein, R A

    2005-01-01

    We outline a method to measure the detailed chemical composition of extragalactic (unresolved) globular clusters (GCs) from echelle spectra of their integrated light. Our goal is to use this method to measure abundance patterns of GCs in distant spiral and elliptical galaxies to constrain their formation histories. To develop this technique we have obtained a ``training set'' of integrated-light spectra of resolved GCs in the Milky Way and LMC by scanning across the clusters during exposures. Our training set also include spectra of individual stars in those GCs from which abundances can be obtained in the normal way to provide a check on our integrated-light results. We present here the preliminary integrated-light analysis of one GC in our training set, NGC 104 (47 Tuc), and outline some of the techniques utilized and problems encountered in that analysis.

  18. Revised Thorium Abundances for Lunar Red Spots

    Science.gov (United States)

    Hagerty, J. J.; Lawrence, D. J.; Elphic, R. C.; Feldman, W. C.; Vaniman, D. T.; Hawke, B. R.

    2005-01-01

    Lunar red spots are features on the nearside of the Moon that are characterized by high albedo and by a strong absorption in the ultraviolet. These red spots include the Gruithuisen domes, the Mairan domes, Hansteen Alpha, the southern portion of Montes Riphaeus, Darney Chi and Tau, Helmet, and an area near the Lassell crater. It has been suggested that many of the red spots are extrusive, nonmare, volcanic features that could be composed of an evolved lithlogy enriched in thorium. In fact, Hawke et al. used morphological characteristics to show that Hansteen Alpha is a nonmare volcanic construct. However, because the apparent Th abundances (6 - 7 ppm) were lower than that expected for evolved rock types, Hawke et al. concluded that Hansteen Alpha was composed of an unknown rock type. Subsequent studies by Lawrence et al. used improved knowledge of the Th spatial distribution for small area features on the lunar surface to revisit the interpretation of Th abundances at the Hansteen Alpha red spot. As part of their study, Lawrence et al. used a forward modeling technique to show that the Th abundance at Hansteen Alpha is not 6 ppm, but is more likely closer to 25 ppm, a value consistent with evolved lithologies. This positive correlation between the morphology and composition of Hansteen Alpha provides support for the presence of evolved lithologies on the lunar surface. It is possible, however, that Hansteen Alpha represents an isolated occurrence of non-mare volcanism. That is why we have chosen to use the forward modeling technique of Lawrence et al. to investigate the Th abundances at other lunar red spots, starting with the Gruithuisen domes. Additional information is included in the original extended abstract.

  19. WIMP abundance and lepton (flavour) asymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Stuke, Maik; Schwarz, Dominik J. [Fakultät für Physik, Universität Bielefeld, Postfach 100131, 33501 Bielefeld (Germany); Starkman, Glenn, E-mail: mstuke@physik.uni-bielefeld.de, E-mail: dschwarz@physik.uni-bielefeld.de, E-mail: glenn.starkman@case.edu [CERCA/ISO, Department of Physics, Case Western Reserve University, Cleveland, OH 44106-7079 (United States)

    2012-03-01

    We investigate how large lepton asymmetries affect the evolution of the early universe at times before big bang nucleosynthesis and in particular how they influence the relic density of WIMP dark matter. In comparison to the standard calculation of the relic WIMP abundance we find a decrease, depending on the lepton flavour asymmetry. We find an effect of up to 20 per cent for lepton flavour asymmetries l{sub f} = O(0.1)

  20. Elemental Abundances of Solar Sibling Candidates

    Science.gov (United States)

    Ramírez, I.; Bajkova, A. T.; Bobylev, V. V.; Roederer, I. U.; Lambert, D. L.; Endl, M.; Cochran, W. D.; MacQueen, P. J.; Wittenmyer, R. A.

    2014-06-01

    Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired high-resolution, high signal-to-noise ratio spectra for 30 of these objects to determine, using detailed elemental abundance analysis, if they could be true solar siblings. Only two of the candidates are found to have solar chemical composition. Updated modeling of the stars' past orbits in a realistic Galactic potential reveals that one of them, HD 162826, satisfies both chemical and dynamical conditions for being a sibling of the Sun. Measurements of rare-element abundances for this star further confirm its solar composition, with the only possible exception of Sm. Analysis of long-term high-precision radial velocity data rules out the presence of hot Jupiters and confirms that this star is not in a binary system. We find that chemical tagging does not necessarily benefit from studying as many elements as possible but instead from identifying and carefully measuring the abundances of those elements that show large star-to-star scatter at a given metallicity. Future searches employing data products from ongoing massive astrometric and spectroscopic surveys can be optimized by acknowledging this fact.

  1. Angel lichen moth abundance and morphology data

    Science.gov (United States)

    Metcalfe, Anya; Kennedy, Theodore A.; Muehlbauer, Jeffrey D.

    2016-01-01

    Two unique datasets on the abundance and morphology of the angel lichen moth ( Cisthene angelus) in Grand Canyon, Arizona, USA were compiled to describe the phenology and life history of this common, but poorly known, species. The abundance data were collected from 2012 to 2013 through a collaboration with river runners in Grand Canyon National Park. These citizen scientists deployed light traps from their campsites for one hour each night of their expedition. Insects were preserved in ethanol on site, and returned to the Southwest Biological Science Center in Flagstaff, Arizona for analysis in the laboratory. A total of 2,437 light trap samples were sorted through, 903 of which contained C. angelus. In total, 73,841 C. angelus were identified and enumerated to create the abundance data set. The morphology dataset is based on a subset of 28 light trap samples from sampling year 2012 (14 from spring and 14 from fall.) It includes gender and forewing lengths for 2,674 individual moths and dry weights for 1,102 of those individuals.

  2. Stellar Mixing and the Primordial Lithium Abundance

    CERN Document Server

    Pinsonneault, M H; Walker, T P; Narayanan, V K

    2002-01-01

    We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We find from a KS test that in the absence of any correction for chemical evolution, the Ryan, Norris, & Beers (1999} sample is fully consistent with mild rotational mixing induced depletion and, therefore, with an initial lithium abundance higher than the observed value. Tests for outliers depend sensitively on the threshold for defining their presence, but we find a 10$--$45% probability that the RNB sample is drawn from the rotationally mixed models with a 0.2 dex median depletion (with lower probabilities corresponding to higher depletion factors). When chemical evolution trends (Li/H versus Fe/H) are treated in the linear plane we find that the dispersion in the RNB sample is not explained by chemical evolution; the inferred bounds on lithium depletion from rotational mixing...

  3. A global database of ant species abundances

    Science.gov (United States)

    Gibb, Heloise; Dunn, Rob R.; Sanders, Nathan J.; Grossman, Blair F.; Photakis, Manoli; Abril, Silvia; Agosti, Donat; Andersen, Alan N.; Angulo, Elena; Armbrecht, Ingre; Arnan, Xavier; Baccaro, Fabricio B.; Bishop, Tom R.; Boulay, Raphael; Bruhl, Carsten; Castracani, Cristina; Cerda, Xim; Del Toro, Israel; Delsinne, Thibaut; Diaz, Mireia; Donoso, David A.; Ellison, Aaron M.; Enriquez, Martha L.; Fayle, Tom M.; Feener Jr., Donald H.; Fisher, Brian L.; Fisher, Robert N.; Fitpatrick, Matthew C.; Gomez, Cristanto; Gotelli, Nicholas J.; Gove, Aaron; Grasso, Donato A.; Groc, Sarah; Guenard, Benoit; Gunawardene, Nihara; Heterick, Brian; Hoffmann, Benjamin; Janda, Milan; Jenkins, Clinton; Kaspari, Michael; Klimes, Petr; Lach, Lori; Laeger, Thomas; Lattke, John; Leponce, Maurice; Lessard, Jean-Philippe; Longino, John; Lucky, Andrea; Luke, Sarah H.; Majer, Jonathan; McGlynn, Terrence P.; Menke, Sean; Mezger, Dirk; Mori, Alessandra; Moses, Jimmy; Munyai, Thinandavha Caswell; Pacheco, Renata; Paknia, Omid; Pearce-Duvet, Jessica; Pfeiffer, Martin; Philpott, Stacy M.; Resasco, Julian; Retana, Javier; Silva, Rogerio R.; Sorger, Magdalena D.; Souza, Jorge; Suarez, Andrew V.; Tista, Melanie; Vasconcelos, Heraldo L.; Vonshak, Merav; Weiser, Michael D.; Yates, Michelle; Parr, Catherine L.

    2017-01-01

    What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51,388 ant abundance and occurrence records of more than 2693 species and 7953 morphospecies from local assemblages collected at 4212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo-referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type and degree of disturbance. The aim of compiling this dataset was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardised methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large-scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing dataset.

  4. Abundances In Very Metal Poor Dwarf Stars

    CERN Document Server

    Cohen, J G; McWilliam, A; Shectman, S; Thompson, I; Wasserburg, G J; Ivans, I I; Dehn, M; Karlsson, T; Melendez, J; Cohen, Judith G.; Christlieb, Norbert; William, Andrew Mc; Shectman, Steve; Thompson, Ian; Ivans, Inese; Dehn, Matthias; Karlsson, Torgny

    2004-01-01

    We discuss the detailed composition of 28 extremely metal-poor dwarfs, 22 of which are from the Hamburg/ESO Survey, based on Keck Echelle spectra. Our sample has a median [Fe/H] of -2.7 dex, extends to -3.5 dex, and is somewhat less metal-poor than was expected from [Fe/H](HK,HES) determined from low resolution spectra. Our analysis supports the existence of a sharp decline in the distribution of halo stars with metallicity below [Fe/H] = -3.0 dex. So far no additional turnoff stars with [Fe/H]}<-3.5 have been identified in our follow up efforts. For the best observed elements between Mg and Ni, we find that the abundance ratios appear to have reached a plateau, i.e. [X/Fe] is approximately constant as a function of [Fe/H], except for Cr, Mn and Co, which show trends of abundance ratios varying with [Fe/H]. These abundance ratios at low metallicity correspond approximately to the yield expected from Type II SN with a narrow range in mass and explosion parameters; high mass Type II SN progenitors are requir...

  5. Chemical abundances and kinematics of barium stars

    CERN Document Server

    de Castro, D B; Roig, F; Jilinski, E; Drake, N A; Chavero, C; Silva, J V Sales

    2016-01-01

    In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scale height, radial velocities, abundances of the Na, Al, $alpha$-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local-thermodynamic-equilibrium model atmospheres of Kurucz and the spectral analysis code {\\sc moog}. We found that the metallicities, the temperatures and the surface gravities for barium stars can not be represented by a single gaussian distribution. The abundances of $alpha$-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heav...

  6. Abundances and Depletions of Interstellar Oxygen

    Science.gov (United States)

    Jensen, A. G.; Rachford, B. L.; Snow, T. P.

    2003-12-01

    We extend previous work on interstellar oxygen abundances with the addition of data from the Far Ultraviolet Spectroscopic Explorer (FUSE). We report on the abundance of interstellar neutral oxygen (OI) for several sightlines, using data from FUSE, the International Spectroscopic Explorer (IUE), and the Hubble Space Telescope (HST). OI column densities are derived by measuring the equivalent widths of several ultraviolet absorption lines, and subsequently fitting those to a curve of growth. The column densities of our best-constrained sightlines show a ratio of O/H that agrees with the current best solar value if dust is considered. We do not see evidence of enhanced depletion of gas-phase oxygen that is systematically variable with respect to the physical parameters of different environments (e.g., reddening or molecular fraction). The column densities of our less well-constrained sightlines show some scatter in O/H, but many agree with the solar value to within errors. We discuss these results in the context of deriving the best methods for determining interstellar abundances, the unresolved question of the best value for O/H in the interstellar medium (ISM), the O/H ratio observed in Galactic stars, and the depletion of gas-phase oxygen onto dust grains. Financial support for this research has been provided by the National Science Foundation GK-12 Program and NASA contract NAS 5-32985.

  7. Abundances in Stars with Debris Disks

    CERN Document Server

    Ritchey, Adam M; Stone, Myra; Wallerstein, George

    2013-01-01

    We present preliminary results of a detailed chemical abundance analysis for a sample of solar-type stars known to exhibit excess infrared emission associated with dusty debris disks. Our sample of 28 stars was selected based on results from the Formation and Evolution of Planetary Systems (FEPS) Spitzer Legacy Program, for the purpose of investigating whether the stellar atmospheres have been polluted with planetary material, which could indicate that the metallicity enhancement in stars with planets is due to metal-rich infall in the later stages of star and planet formation. The preliminary results presented here consist of precise abundances for 15 elements (C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Fe, Co, and Ni) for half of the stars in our sample. We find that none of the stars investigated so far exhibit the expected trend of increasing elemental abundance with increasing condensation temperature, which would result from the stars having accreted planetary debris. Rather, the slopes of linear least...

  8. Abundance analyses of cool extreme helium stars

    CERN Document Server

    Pandey, G; Lambert, D L; Jeffery, C S; Asplund, M; Pandey, Gajendra; Lambert, David L.; Asplund, Martin

    2001-01-01

    Extreme helium stars (EHe) with effective temperatures from 8000K to 13000K are among the coolest EHe stars and overlap the hotter R CrB stars in effective temperature. The cool EHes may represent an evolutionary link between the hot EHes and the R CrBs. Abundance analyses of four cool EHes are presented. To test for an evolutionary connection, the chemical compositions of cool EHes are compared with those of hot EHes and R CrBs. Relative to Fe, the N abundance of these stars is intermediate between those of hot EHes and R CrBs. For the R CrBs, the metallicity M derived from the mean of Si and S appears to be more consistent with the kinematics than that derived from Fe. When metallicity M derived from Si and S replaces Fe, the observed N abundances of EHes and R CrBs fall at or below the upper limit corresponding to thorough conversion of initial C and O to N. There is an apparent difference between the composition of R CrBs and EHes; the former having systematically higher [N/M] ratios. The material present...

  9. Water Abundance in Molecular Cloud Cores

    CERN Document Server

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

    2000-01-01

    We present Submillimeter Wave Astronomy Satellite (SWAS) observations of the 1_{10}-1_{01} transition of ortho-water at 557 GHz toward 12 molecular cloud cores. The water emission was detected in NGC 7538, Rho Oph A, NGC 2024, CRL 2591, W3, W3(OH), Mon R2, and W33, and was not detected in TMC-1, L134N, and B335. We also present a small map of the water emission in S140. Observations of the H_2^{18}O line were obtained toward S140 and NGC 7538, but no emission was detected. The abundance of ortho-water relative to H_2 in the giant molecular cloud cores was found to vary between 6x10^{-10} and 1x10^{-8}. Five of the cloud cores in our sample have previous water detections; however, in all cases the emission is thought to arise from hot cores with small angular extents. The water abundance estimated for the hot core gas is at least 100 times larger than in the gas probed by SWAS. The most stringent upper limit on the ortho-water abundance in dark clouds is provided in TMC-1, where the 3-sigma upper limit on the ...

  10. The shape of terrestrial abundance distributions.

    Science.gov (United States)

    Alroy, John

    2015-09-01

    Ecologists widely accept that the distribution of abundances in most communities is fairly flat but heavily dominated by a few species. The reason for this is that species abundances are thought to follow certain theoretical distributions that predict such a pattern. However, previous studies have focused on either a few theoretical distributions or a few empirical distributions. I illustrate abundance patterns in 1055 samples of trees, bats, small terrestrial mammals, birds, lizards, frogs, ants, dung beetles, butterflies, and odonates. Five existing theoretical distributions make inaccurate predictions about the frequencies of the most common species and of the average species, and most of them fit the overall patterns poorly, according to the maximum likelihood-related Kullback-Leibler divergence statistic. Instead, the data support a low-dominance distribution here called the "double geometric." Depending on the value of its two governing parameters, it may resemble either the geometric series distribution or the lognormal series distribution. However, unlike any other model, it assumes both that richness is finite and that species compete unequally for resources in a two-dimensional niche landscape, which implies that niche breadths are variable and that trait distributions are neither arrayed along a single dimension nor randomly associated. The hypothesis that niche space is multidimensional helps to explain how numerous species can coexist despite interacting strongly.

  11. Elemental abundances of solar sibling candidates

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez, I.; Lambert, D. L.; Endl, M.; Cochran, W. D.; MacQueen, P. J. [McDonald Observatory and Department of Astronomy, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, Texas 78712-1205 (United States); Bajkova, A. T.; Bobylev, V. V. [Central (Pulkovo) Astronomical Observatory of RAS, 65/1, Pulkovskoye Chaussee, St. Petersburg 196140 (Russian Federation); Roederer, I. U. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Wittenmyer, R. A. [School of Physics, UNSW Australia, Sydney 2052 (Australia)

    2014-06-01

    Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired high-resolution, high signal-to-noise ratio spectra for 30 of these objects to determine, using detailed elemental abundance analysis, if they could be true solar siblings. Only two of the candidates are found to have solar chemical composition. Updated modeling of the stars' past orbits in a realistic Galactic potential reveals that one of them, HD 162826, satisfies both chemical and dynamical conditions for being a sibling of the Sun. Measurements of rare-element abundances for this star further confirm its solar composition, with the only possible exception of Sm. Analysis of long-term high-precision radial velocity data rules out the presence of hot Jupiters and confirms that this star is not in a binary system. We find that chemical tagging does not necessarily benefit from studying as many elements as possible but instead from identifying and carefully measuring the abundances of those elements that show large star-to-star scatter at a given metallicity. Future searches employing data products from ongoing massive astrometric and spectroscopic surveys can be optimized by acknowledging this fact.

  12. Low 60Fe Abundance in Semarkona and Sahara 99555

    Science.gov (United States)

    Tang, Haolan; Dauphas, Nicolas

    2015-03-01

    Iron-60 (t1/2 = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of 60Fe(60Fe/56Fe ≈ 4 × 10-7) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that 60Fe was present in the early Solar System at a much lower level (60Fe/56Fe ≈ 10-8). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ˜2× chondritic. Here, we show that the initial 60Fe/56Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ˜24× chondritic is (5.39 ± 3.27) × 10-9. We also establish the initial 60Fe/56Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10-9. These results demonstrate that the initial abundance of 60Fe at Solar System birth was low, corresponding to an initial 60Fe/56Fe ratio of (1.01 ± 0.27) × 10-8.

  13. LOW {sup 60}FE ABUNDANCE IN SEMARKONA AND SAHARA 99555

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Haolan; Dauphas, Nicolas, E-mail: haolantang@ucla.edu [Origins Lab, Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago IL 60637 (United States)

    2015-03-20

    Iron-60 (t{sub 1/2} = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of {sup 60}Fe({sup 60}Fe/{sup 56}Fe ≈ 4 × 10{sup −7}) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that {sup 60}Fe was present in the early Solar System at a much lower level ({sup 60}Fe/{sup 56}Fe ≈ 10{sup −8}). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ∼2× chondritic. Here, we show that the initial {sup 60}Fe/{sup 56}Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ∼24× chondritic is (5.39 ± 3.27) × 10{sup −9}. We also establish the initial {sup 60}Fe/{sup 56}Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10{sup −9}. These results demonstrate that the initial abundance of {sup 60}Fe at Solar System birth was low, corresponding to an initial {sup 60}Fe/{sup 56}Fe ratio of (1.01 ± 0.27) × 10{sup −8}.

  14. Magnetoresistive waves in plasmas

    Science.gov (United States)

    Felber, F. S.; Hunter, R. O., Jr.; Pereira, N. R.; Tajima, T.

    1982-10-01

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed.

  15. Abundant Solar Nebula Solids in Comets

    Science.gov (United States)

    Messenger, S.; Keller, L. P.; Nakamura-Messenger, K.; Nguyen, A. N.; Clemett, S.

    2016-01-01

    Comets have been proposed to consist of unprocessed interstellar materials together with a variable amount of thermally annealed interstellar grains. Recent studies of cometary solids in the laboratory have shown that comets instead consist of a wide range of materials from across the protoplanetary disk, in addition to a minor complement of interstellar materials. These advances were made possible by the return of direct samples of comet 81P/Wild 2 coma dust by the NASA Stardust mission and recent advances in microscale analytical techniques. Isotopic studies of 'cometary' chondritic porous interplanetary dust particles (CP-IDPs) and comet 81P/Wild 2 Stardust samples show that preserved interstellar materials are more abundant in comets than in any class of meteorite. Identified interstellar materials include sub-micron-sized presolar silicates, oxides, and SiC dust grains and some fraction of the organic material that binds the samples together. Presolar grain abundances reach 1 weight percentage in the most stardust-rich CP-IDPs, 50 times greater than in meteorites. Yet, order of magnitude variations in presolar grain abundances among CP-IDPs suggest cometary solids experienced significant variations in the degree of processing in the solar nebula. Comets contain a surprisingly high abundance of nebular solids formed or altered at high temperatures. Comet 81P/Wild 2 samples include 10-40 micron-sized, refractory Ca- Al-rich inclusion (CAI)-, chondrule-, and ameboid olivine aggregate (AOA)-like materials. The O isotopic compositions of these refractory materials are remarkably similar to their meteoritic counterparts, ranging from 5 percent enrichments in (sup 16) O to near-terrestrial values. Comet 81P/Wild 2 and CP-IDPs also contain abundant Mg-Fe crystalline and amorphous silicates whose O isotopic compositions are also consistent with Solar System origins. Unlike meteorites, that are dominated by locally-produced materials, comets appear to be composed of

  16. Impact of thermal diffusion and other abundance anomalies on cosmological uses of galaxy clusters

    CERN Document Server

    Medvedev, P; Sazonov, S; Shtykovskiy, P

    2013-01-01

    Depending on the topology of the magnetic field and characteristics of turbulent motions, diffusion can significantly affect the distribution of elements, in particular helium, in the intracluster medium (ICM). As has been noted previously, an incorrect assumption about the helium abundance will lead to an error in the iron abundance determined from X-ray spectroscopy. The corresponding effect on the temperature measurement is negligibly small. An incorrectly assumed helium abundance will also lead to a systematic error in angular distance measurements based on X-ray and Sunyaev-Zeldovich (SZ) observations of clusters of galaxies. Its magnitude is further amplified by the associated error in the metal abundance determination, the impact being larger at lower ICM temperatures. Overall, a factor of 2-5 error in the helium abundance will lead to an ~ 10-25 % error in the angular distance. We solve the full set of Burgers equations for a multi-component intracluster plasma to determine the maximal effect of diffu...

  17. Electrosurgical plasmas

    Science.gov (United States)

    Stalder, Kenneth R.; McMillen, Donald F.; Woloszko, Jean

    2005-06-01

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  18. Electrosurgical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)

    2005-06-07

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  19. Plasma physics

    CERN Document Server

    Cairns, R A

    1985-01-01

    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  20. Plasma pharmacy - physical plasma in pharmaceutical applications.

    Science.gov (United States)

    von Woedtke, Th; Haertel, B; Weltmann, K-D; Lindequist, U

    2013-07-01

    During the last years the use of physical plasma for medical applications has grown rapidly. A multitude of findings about plasma-cell and plasma-tissue interactions and its possible use in therapy have been provided. One of the key findings of plasma medical basic research is that several biological effects do not result from direct plasma-cell or plasma-tissue interaction but are mediated by liquids. Above all, it was demonstrated that simple liquids like water or physiological saline, are antimicrobially active after treatment by atmospheric pressure plasma and that these effects are attributable to the generation of different low-molecular reactive species. Besides, it could be shown that plasma treatment leads to the stimulation of specific aspects of cell metabolism and to a transient and reversible increase of diffusion properties of biological barriers. All these results gave rise to think about another new and innovative field of medical plasma application. In contrast to plasma medicine, which means the direct use of plasmas on or in the living organism for direct therapeutic purposes, this field - as a specific field of medical plasma application - is called plasma pharmacy. Based on the present state of knowledge, most promising application fields of plasma pharmacy might be: plasma-based generation of biologically active liquids; plasma-based preparation, optimization, or stabilization of - mainly liquid - pharmaceutical preparations; support of drug transport across biological barriers; plasma-based stimulation of biotechnological processes.

  1. Relative quantification of several plasma proteins during liver transplantation surgery.

    Science.gov (United States)

    Parviainen, Ville; Joenväärä, Sakari; Tukiainen, Eija; Ilmakunnas, Minna; Isoniemi, Helena; Renkonen, Risto

    2011-01-01

    Plasma proteome is widely used in studying changes occurring in human body during disease or other disturbances. Immunological methods are commonly used in such studies. In recent years, mass spectrometry has gained popularity in high-throughput analysis of plasma proteins. In this study, we tested whether mass spectrometry and iTRAQ-based protein quantification might be used in proteomic analysis of human plasma during liver transplantation surgery to characterize changes in protein abundances occurring during early graft reperfusion. We sampled blood from systemic circulation as well as blood entering and exiting the liver. After immunodepletion of six high-abundant plasma proteins, trypsin digestion, iTRAQ labeling, and cation-exchange fractionation, the peptides were analyzed by reverse phase nano-LC-MS/MS. In total, 72 proteins were identified of which 31 could be quantified in all patient specimens collected. Of these 31 proteins, ten, mostly medium-to-high abundance plasma proteins with a concentration range of 50-2000 mg/L, displayed relative abundance change of more than 10%. The changes in protein abundance observed in this study allow further research on the role of several proteins in ischemia-reperfusion injury during liver transplantation and possibly in other surgery.

  2. Relative Quantification of Several Plasma Proteins during Liver Transplantation Surgery

    Directory of Open Access Journals (Sweden)

    Ville Parviainen

    2011-01-01

    Full Text Available Plasma proteome is widely used in studying changes occurring in human body during disease or other disturbances. Immunological methods are commonly used in such studies. In recent years, mass spectrometry has gained popularity in high-throughput analysis of plasma proteins. In this study, we tested whether mass spectrometry and iTRAQ-based protein quantification might be used in proteomic analysis of human plasma during liver transplantation surgery to characterize changes in protein abundances occurring during early graft reperfusion. We sampled blood from systemic circulation as well as blood entering and exiting the liver. After immunodepletion of six high-abundant plasma proteins, trypsin digestion, iTRAQ labeling, and cation-exchange fractionation, the peptides were analyzed by reverse phase nano-LC-MS/MS. In total, 72 proteins were identified of which 31 could be quantified in all patient specimens collected. Of these 31 proteins, ten, mostly medium-to-high abundance plasma proteins with a concentration range of 50–2000 mg/L, displayed relative abundance change of more than 10%. The changes in protein abundance observed in this study allow further research on the role of several proteins in ischemia-reperfusion injury during liver transplantation and possibly in other surgery.

  3. The predominant cholecystokinin in human plasma and intestine is cholecystokinin-33

    DEFF Research Database (Denmark)

    Rehfeld, J F; Sun, G; Christensen, T;

    2001-01-01

    Cholecystokinin (CCK) occurs in multiple molecular forms; the major ones are CCK-58, -33, -22, and -8. Their relative abundance in human plasma and intestine, however, is debated. To settle the issue, extracts of intestinal biopsies and plasma from 10 human subjects have been examined...... is the second most abundant ( approximately 34% and 30%, respectively). In contrast, CCK-58 is less abundant in human intestines ( approximately 18%) and plasma ( approximately 11%). Its predominance in feline intestines, however, was confirmed. Hence, the results show a significant species variation...

  4. Physics of the plasma universe

    CERN Document Server

    Peratt, Anthony L

    2015-01-01

    Today many scientists recognize plasma as the key element to understanding new observations in near-Earth, interplanetary, interstellar, and intergalactic space; in stars, galaxies, and clusters of galaxies, and throughout the observable universe. Physics of the Plasma Universe, 2nd Edition is an update of observations made across the entire cosmic electromagnetic spectrum over the two decades since the publication of the first edition. It addresses paradigm changing discoveries made by telescopes, planetary probes, satellites, and radio and space telescopes. The contents are the result of the author's 37 years research at Livermore and Los Alamos National Laboratories, and the U.S. Department of Energy. This book covers topics such as the large-scale structure and the filamentary universe; the formation of magnetic fields and galaxies, active galactic nuclei and quasars, the origin and abundance of light elements, star formation and the evolution of solar systems, and cosmic rays. Chapters 8 and 9 are based ...

  5. Can occupancy-abundance models be used to monitor wolf abundance?

    Directory of Open Access Journals (Sweden)

    M Cecilia Latham

    Full Text Available Estimating the abundance of wild carnivores is of foremost importance for conservation and management. However, given their elusive habits, direct observations of these animals are difficult to obtain, so abundance is more commonly estimated from sign surveys or radio-marked individuals. These methods can be costly and difficult, particularly in large areas with heavy forest cover. As an alternative, recent research has suggested that wolf abundance can be estimated from occupancy-abundance curves derived from "virtual" surveys of simulated wolf track networks. Although potentially more cost-effective, the utility of this approach hinges on its robustness to violations of its assumptions. We assessed the sensitivity of the occupancy-abundance approach to four assumptions: variation in wolf movement rates, changes in pack cohesion, presence of lone wolves, and size of survey units. Our simulations showed that occupancy rates and wolf pack abundances were biased high if track surveys were conducted when wolves made long compared to short movements, wolf packs were moving as multiple hunting units as opposed to a cohesive pack, and lone wolves were moving throughout the surveyed landscape. We also found that larger survey units (400 and 576 km2 were more robust to changes in these factors than smaller survey units (36 and 144 km2. However, occupancy rates derived from large survey units rapidly reached an asymptote at 100% occupancy, suggesting that these large units are inappropriate for areas with moderate to high wolf densities (>15 wolves/1,000 km2. Virtually-derived occupancy-abundance relationships can be a useful method for monitoring wolves and other elusive wildlife if applied within certain constraints, in particular biological knowledge of the surveyed species needs to be incorporated into the design of the occupancy surveys. Further, we suggest that the applicability of this method could be extended by directly incorporating some of its

  6. Air plasma effect on dental disinfection

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, S.; Murata, R. M.; Saxena, D. [Department of Basic Sciences and Craniofacial Biology, College of Dentistry, New York University, New York, New York 10010 (United States); Kuo, S. P.; Chen, C. Y.; Huang, K. J. [Department of Electrical and Computer Engineering, Polytechnic Institute of New York University, Brooklyn, New York 11202 (United States); Popovic, S. [Department of Physics, Old Dominion University, Norfolk, Virginia 23529 (United States)

    2011-07-15

    A nonthermal low temperature air plasma jet is characterized and applied to study the plasma effects on oral pathogens and biofilms. Experiments were performed on samples of six defined microorganisms' cultures, including those of gram-positive bacteria and fungi, and on a cultivating biofilm sample of Streptococcus mutans UA159. The results show that the plasma jet creates a zone of microbial growth inhibition in each treated sample; the zone increases with the plasma treatment time and expands beyond the entire region directly exposed to the plasma jet. With 30s plasma treatment twice daily during 5 days of biofilm cultivation, its formation was inhibited. The viability of S. mutans cells in the treated biofilms dropped to below the measurable level and the killed bacterial cells concentrated to local regions as manifested by the fluorescence microscopy via the environmental scanning electron microscope. The emission spectroscopy of the jet indicates that its plasma effluent carries an abundance of reactive atomic oxygen, providing catalyst for the observed plasma effect.

  7. Air plasma effect on dental disinfection

    Science.gov (United States)

    Duarte, S.; Kuo, S. P.; Murata, R. M.; Chen, C. Y.; Saxena, D.; Huang, K. J.; Popovic, S.

    2011-07-01

    A nonthermal low temperature air plasma jet is characterized and applied to study the plasma effects on oral pathogens and biofilms. Experiments were performed on samples of six defined microorganisms' cultures, including those of gram-positive bacteria and fungi, and on a cultivating biofilm sample of Streptococcus mutans UA159. The results show that the plasma jet creates a zone of microbial growth inhibition in each treated sample; the zone increases with the plasma treatment time and expands beyond the entire region directly exposed to the plasma jet. With 30s plasma treatment twice daily during 5 days of biofilm cultivation, its formation was inhibited. The viability of S. mutans cells in the treated biofilms dropped to below the measurable level and the killed bacterial cells concentrated to local regions as manifested by the fluorescence microscopy via the environmental scanning electron microscope. The emission spectroscopy of the jet indicates that its plasma effluent carries an abundance of reactive atomic oxygen, providing catalyst for the observed plasma effect.

  8. The primordial helium abundance from updated emissivities

    Energy Technology Data Exchange (ETDEWEB)

    Aver, Erik [Department of Physics, Gonzaga University, 502 E Boone Ave, Spokane, WA, 99258 (United States); Olive, Keith A.; Skillman, Evan D. [School of Physics and Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN, 55455 (United States); Porter, R.L., E-mail: aver@gonzaga.edu, E-mail: olive@umn.edu, E-mail: ryanlporter@gmail.com, E-mail: skillman@astro.umn.edu [Department of Physics and Astronomy, University of Georgia, Athens, GA, 30602 (United States)

    2013-11-01

    Observations of metal-poor extragalactic H II regions allow the determination of the primordial helium abundance, Y{sub p}. The He I emissivities are the foundation of the model of the H II region's emission. Porter, Ferland, Storey, and Detisch (2012) have recently published updated He I emissivities based on improved photoionization cross-sections. We incorporate these new atomic data and update our recent Markov Chain Monte Carlo analysis of the dataset published by Izotov, Thuan, and Stasi'nska (2007). As before, cuts are made to promote quality and reliability, and only solutions which fit the data within 95% confidence level are used to determine the primordial He abundance. The previously qualifying dataset is almost entirely retained and with strong concordance between the physical parameters. Overall, an upward bias from the new emissivities leads to a decrease in Y{sub p}. In addition, we find a general trend to larger uncertainties in individual objects (due to changes in the emissivities) and an increased variance (due to additional objects included). From a regression to zero metallicity, we determine Y{sub p} = 0.2465 ± 0.0097, in good agreement with the BBN result, Y{sub p} = 0.2485 ± 0.0002, based on the Planck determination of the baryon density. In the future, a better understanding of why a large fraction of spectra are not well fit by the model will be crucial to achieving an increase in the precision of the primordial helium abundance determination.

  9. The Primordial Abundance of 4He Revisited

    Science.gov (United States)

    Izotov, Yuri I.; Thuan, Trinh X.

    1998-06-01

    We use a sample of 45 low-metallicity H II regions to determine the primordial helium abundance Yp with a precision of better than 1%. The data includes new spectrophotometric observations of 15 blue compact galaxies (BCGs) with oxygen abundance 12 + log (O/H) between 7.83 and 8.35 (Z⊙/13 Lipovetsky, but higher than previous determinations (Yp = 0.230-0.234). Part of the difference comes from the fact that previous investigators have used the northwest component of I Zw 18 in the determination of Yp. This component is subject to strong underlying He I stellar absorption that reduces the He I line intensities by 5%-25%. The derived Y is 0.233 +/- 0.008 from the He I λ6678 line. Instead, by using the southeast component of I Zw 18, which is much less subject to underlying He I stellar absorption, we obtain Y = 0.242 +/- 0.009. The mean Y of the two most metal-deficient BCGs, I Zw 18 and SBS 0335-052, is Ȳ=0.245+/-0.004, in excellent agreement with the Yp derived from the linear regressions. We derive a slope dY/dZ = 2.3 +/- 1.0, considerably smaller than those derived before. With this smaller slope and taking into account the errors, chemical evolution models with an outflow of well-mixed material can be built for star-forming dwarf galaxies that satisfy all the observational constraints. Our Yp gives Ωbh250=0.058+/-0.007, consistent with the lower limit set by dynamical measurements and X-ray observations of clusters of galaxies. It is also consistent, within the framework of standard big bang nucleosynthesis theory, with measurements of primordial 7Li in galactic halo stars, and at the 1 σ level with the D/H abundance measured in absorption systems toward quasars by Tytler & Burles.

  10. Cosmic ray source abundance of calcium

    CERN Document Server

    Perron, C

    1978-01-01

    Re-examines the results of experiments in which ultra-high purity iron targets were irradiated by protons from the two CERN accelerators (600 MeV and 21 GeV); the spallation products were then chemically separated, and their isotopic composition determined by mass spectrometry. Ratios of cross-sections for calcium production by spallation of iron show that /sup 42/Ca, /sup 43/Ca and /sup 44/Ca have about the same abundance, about 10-15% that of iron, confirming earlier studies. (11 refs).

  11. Detecting significant changes in protein abundance

    Directory of Open Access Journals (Sweden)

    Kai Kammers

    2015-06-01

    Full Text Available We review and demonstrate how an empirical Bayes method, shrinking a protein's sample variance towards a pooled estimate, leads to far more powerful and stable inference to detect significant changes in protein abundance compared to ordinary t-tests. Using examples from isobaric mass labelled proteomic experiments we show how to analyze data from multiple experiments simultaneously, and discuss the effects of missing data on the inference. We also present easy to use open source software for normalization of mass spectrometry data and inference based on moderated test statistics.

  12. Interstellar Abundances in the Magellanic Clouds

    OpenAIRE

    Welty, Daniel E.

    2001-01-01

    We summarize recent studies of the predominantly neutral gas in the Magellanic Clouds (MC), based on combinations of high-resolution optical spectra and UV spectra obtained with IUE, HST, and FUSE. Similarities in relative gas-phase abundances for Galactic and MC sightlines with relatively low N(H) had suggested that the depletion patterns might be similar in the three galaxies -- at least where the depletions are relatively mild. New STIS spectra of one higher N(H) SMC sightline, however, ha...

  13. Lightest sterile neutrino abundance within the nuMSM

    CERN Document Server

    Asaka, T; Shaposhnikov, M E; Asaka, Takehiko; Laine, Mikko; Shaposhnikov, Mikhail

    2007-01-01

    We determine the abundance of the lightest (dark matter) sterile neutrinos created in the Early Universe due to active-sterile neutrino transitions from the thermal plasma. Our starting point is the field-theoretic formula for the sterile neutrino production rate, derived in our previous work [JHEP 06(2006)053], which allows to systematically incorporate all relevant effects, and also to analyse various hadronic uncertainties. Our numerical results differ moderately from previous computations in the literature, and lead to an absolute upper bound on the mixing angles of the dark matter sterile neutrino. Comparing this bound with existing astrophysical X-ray constraints, we find that the Dodelson-Widrow scenario, which proposes sterile neutrinos generated by active-sterile neutrino transitions to be the sole source of dark matter, is only possible for sterile neutrino masses lighter than 3.5 keV (6 keV if all hadronic uncertainties are pushed in one direction and the most stringent X-ray bounds are relaxed by ...

  14. Non-additive effects of genotypic diversity increase floral abundance and abundance of floral visitors.

    Directory of Open Access Journals (Sweden)

    Mark A Genung

    Full Text Available BACKGROUND: In the emerging field of community and ecosystem genetics, genetic variation and diversity in dominant plant species have been shown to play fundamental roles in maintaining biodiversity and ecosystem function. However, the importance of intraspecific genetic variation and diversity to floral abundance and pollinator visitation has received little attention. METHODOLOGY/PRINCIPAL FINDINGS: Using an experimental common garden that manipulated genotypic diversity (the number of distinct genotypes per plot of Solidago altissima, we document that genotypic diversity of a dominant plant can indirectly influence flower visitor abundance. Across two years, we found that 1 plant genotype explained 45% and 92% of the variation in flower visitor abundance in 2007 and 2008, respectively; and 2 plant genotypic diversity had a positive and non-additive effect on floral abundance and the abundance of flower visitors, as plots established with multiple genotypes produced 25% more flowers and received 45% more flower visits than would be expected under an additive model. CONCLUSIONS/SIGNIFICANCE: These results provide evidence that declines in genotypic diversity may be an important but little considered factor for understanding plant-pollinator dynamics, with implications for the global decline in pollinators due to reduced plant diversity in both agricultural and natural ecosystems.

  15. VLT\\/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies I. Nucleosynthesis and Abundance Ratios

    CERN Document Server

    Shetrone, M; Tolstoy, E; Primas, F; Hill, V; Kaufer, A

    2003-01-01

    We have used UVES on VLT-UT2 to take spectra of 15 red giants in the Sculptor, Fornax, Carina and Leo I dwarf spheroidal galaxies. We measure the abundances of alpha, iron peak, s and r-process elements. No dSph giants in our sample show the deep mixing abundance pattern seen in nearly all globular clusters. At a given metallicity, the dSph giants exhibit lower [el/Fe] abundance ratios for the alpha elements than stars in the Galactic halo. This can be caused by a slow star formation rate and contribution from Type Ia SN, and/or a small star formation event (low total mass) and mass dependent Type II SN yields. Differences in the even-Z [el/Fe] ratios between these galaxies, as well as differences in the evolution of the s&r-process elements are interpreted in terms of their star formation histories. Comparison of the dSph abundances with those of the Galactic halo reveals some consistencies. In particular, we find stars that mimic the abundance pattern found by Nissen & Shuster (1997) for metal-rich,...

  16. Metal Abundances of KISS Galaxies. V. Nebular Abundances of Fifteen Intermediate Luminosity Star-Forming Galaxies

    CERN Document Server

    Hirschauer, Alec S; Bresolin, Fabio; Saviane, Ivo; Yegorova, Irina

    2015-01-01

    We present high S/N spectroscopy of 15 emission-line galaxies (ELGs) cataloged in the KPNO International Spectroscopic Survey (KISS), selected for their possession of high equivalent width [O III] lines. The primary goal of this study was to attempt to derive direct-method ($T_e$) abundances for use in constraining the upper-metallicity branch of the $R_{23}$ relation. The spectra cover the full optical region from [O II]{\\lambda}{\\lambda}3726,3729 to [S III]{\\lambda}{\\lambda}9069,9531 and include the measurement of [O III]{\\lambda}4363 in 13 objects. From these spectra, we determine abundance ratios of helium, nitrogen, oxygen, neon, sulfur, and argon. We find these galaxies to predominantly possess oxygen abundances in the range of 8.0 $\\lesssim$ 12+log(O/H) $\\lesssim$ 8.3. We present a comparison of direct-method abundances with empirical SEL techniques, revealing several discrepancies. We also present a comparison of direct-method oxygen abundance calculations using electron temperatures determined from e...

  17. Metal Abundances of KISS Galaxies. V. Nebular Abundances of 15 Intermediate Luminosity Star-forming Galaxies

    Science.gov (United States)

    Hirschauer, Alec S.; Salzer, John J.; Bresolin, Fabio; Saviane, Ivo; Yegorova, Irina

    2015-09-01

    We present high signal-to-noise ratio spectroscopy of 15 emission-line galaxies cataloged in the KPNO International Spectroscopic Survey, selected for their possession of high equivalent width [O iii] lines. The primary goal of this study was to attempt to derive direct-method (Te) abundances for use in constraining the upper-metallicity branch of the {R}23 relation. The spectra cover the full optical region from [O ii]λλ3726,3729 to [S iii]λλ9069,9531 and include the measurement of [O iii]λ4363 in 13 objects. From these spectra, we determine abundance ratios of helium, nitrogen, oxygen, neon, sulfur, and argon. We find these galaxies to predominantly possess oxygen abundances in the range of 8.0 ≲ 12+log(O/H) ≲ 8.3. We present a comparison of direct-method abundances with empirical strong-emission-line techniques, revealing several discrepancies. We also present a comparison of direct-method oxygen abundance calculations using electron temperatures determined from emission lines of O++ and S++, finding a small systematic shift to lower Te (∼1184 K) and higher metallicity (∼0.14 dex) for sulfur-derived Te compared to oxygen-derived Te. Finally, we explore in some detail the different spectral activity types of targets in our sample, including regular star-forming galaxies, those with suspected AGN contamination, and a local pair of low-metallicity, high-luminosity compact objects.

  18. Immunodepletion of high-abundant proteins from acute and chronic wound fluids to elucidate low-abundant regulators in wound healing

    Directory of Open Access Journals (Sweden)

    Chojnacki Caroline

    2010-12-01

    Full Text Available Abstract Background The process of wound healing consists of several well distinguishable and finely tuned phases. For most of these phases specific proteins have been characterized, although the underlying mechanisms of regulation are not yet fully understood. It is an open question as to whether deficits in wound healing can be traced back to chronic illnesses such as diabetes mellitus. Previous research efforts in this field focus largely on a restricted set of marker proteins due to the limitations detection by antibodies imposes. For mechanistic purposes the elucidation of differences in acute and chronic wounds can be addressed by a less restricted proteome study. Mass spectrometric (MS methods, e.g. multi dimensional protein identification technology (MudPIT, are well suitable for this complex theme of interest. The human wound fluid proteome is extremely complex, as is human plasma. Therefore, high-abundant proteins often mask the mass spectrometric detection of lower-abundant ones, which makes a depletion step of such predominant proteins inevitable. Findings In this study a commercially available immunodepletion kit was evaluated for the detection of low-abundant proteins from wound fluids. The dynamic range of the entire workflow was significantly increased to 5-6 orders of magnitude, which makes low-abundant regulatory proteins involved in wound healing accessible for MS detection. Conclusion The depletion of abundant proteins is absolutely necessary in order to analyze highly complex protein mixtures such as wound fluids using mass spectrometry. For this the used immunodepletion kit is a first but important step in order to represent the entire dynamic range of highly complex protein mixtures in the future.

  19. Beryllium abundances in stars hosting giant planets

    CERN Document Server

    Santos, N C; Israelian, G; Mayor, M; Rebolo, R; García-Gíl, A; Pérez de Taoro, M R; Randich, S

    2002-01-01

    We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated stars. Predictions from current models are compared with the derived abundances and suggestions are provided to explain the observed inconsistencies. We show that while still not clear, the results suggest that theoretical models may have to be revised for stars with Teff<5500K. On the other hand, a comparison between planet host and non-planet host stars shows no clear difference between both populations. Although preliminary, this result favors a ``primordial'' origin for the metallicity ``excess'' observed for the planetary host stars. Under this assumption, i.e. that there would be no differences between stars with and without giant planets, the light element depletion pattern of our sample of stars may also be used to further investigate and constraint Li and Be deple...

  20. Elemental Abundances of Solar Sibling Candidates

    CERN Document Server

    Ramirez, I; Bobylev, V V; Roederer, I U; Lambert, D L; Endl, M; Cochran, W D; MacQueen, P J; Wittenmyer, R A

    2014-01-01

    Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired high resolution, high signal-to-noise ratio spectra for 30 of these objects to determine, using detailed elemental abundance analysis, if they could be true solar siblings. Only two of the candidates are found to have solar chemical composition. Updated modeling of the stars' past orbits in a realistic Galactic potential reveals that one of them, HD162826, satisfies both chemical and dynamical conditions for being a sibling of the Sun. Measurements of rare-element abundances for this star further confirm its solar composition, with the only possible exception of Sm. Analysis of long-term high-precision radial velocity data rules out the presence of hot Jupiters and confirms that this star is not in a binary system. We find that chemical tagging does not necessarily benefit from studying a...

  1. Abundance Anomalies In Tidal Disruption Events

    CERN Document Server

    Kochanek, C S

    2015-01-01

    The ~10% of tidal disruption events (TDEs) due to stars more massive than the Sun should show abundance anomalies due to stellar evolution in helium, carbon and nitrogen, but not oxygen. Helium is always enhanced, but only by up to ~25% on average because it becomes inaccessible once it is sequestered in the high density core as the star leaves the main sequence. However, portions of the debris associated with the disrupted core of a main sequence star can be enhanced in helium by factors of 2-3 for debris at a common orbital period. These helium abundance variations may be a contributor to the observed diversity of hydrogen and helium line strengths in TDEs. A still more striking anomaly is the rapid enhancement of nitrogen and the depletion of carbon due to the CNO cycle -- stars more massive than the Sun quickly show an increase in their average N/C ratio by factors of 3-10. Because low mass stars evolve slowly and high mass stars are rare, TDEs showing high N/C will almost all be due to 1-2Msun stars disr...

  2. Manganese abundances in Galactic bulge red giants

    CERN Document Server

    Barbuy, B; Zoccali, M; Minniti, D; Renzini, A; Ortolani, S; Gomez, A; Trevisan, M; Dutra, N

    2013-01-01

    Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut beween the matter ejected and falling back onto the remnant, electron and neutron excesses, mixing fallback, and explosion energy. Manganese is also produced in type Ia SNe. The aim of this work is the study of abundances of the iron-peak element Mn in 56 bulge giants, among which 13 are red clump stars. Four bulge fields along the minor axis are inspected. The study of abundances of Mn-over-Fe as a function of metallicity in the Galactic bulge may shed light on its production mechanisms. High-resolution spectra were obtained using the FLAMES+UVES spectrograph on the Very Large Telescope. The spectra were obtained within a program to observe 800 stars using the GIRAFFE spectrograph, together with the present UVES spectra. We aim at identifying the chemical evolution of manganese, as a function of metallicity, in the Gala...

  3. Automatic abundance analysis of high resolution spectra

    CERN Document Server

    Bonifacio, P; Bonifacio, Piercarlo; Caffau, Elisabetta

    2003-01-01

    We describe an automatic procedure for determining abundances from high resolution spectra. Such procedures are becoming increasingly important as large amounts of data are delivered from 8m telescopes and their high-multiplexing fiber facilities, such as FLAMES on ESO-VLT. The present procedure is specifically targeted for the analysis of spectra of giants in the Sgr dSph; however, the procedure may be, in principle, tailored to analyse stars of any type. Emphasis is placed on the algorithms and on the stability of the method; the external accuracy rests, ultimately, on the reliability of the theoretical models (model-atmospheres, synthetic spectra) used to interpret the data. Comparison of the results of the procedure with the results of a traditional analysis for 12 Sgr giants shows that abundances accurate at the level of 0.2 dex, comparable with that of traditional analysis of the same spectra, may be derived in a fast and efficient way. Such automatic procedures are not meant to replace the traditional ...

  4. Occupancy as a surrogate for abundance estimation

    Directory of Open Access Journals (Sweden)

    MacKenzie, D. I.

    2004-06-01

    Full Text Available In many monitoring programmes it may be prohibitively expensive to estimate the actual abundance of a bird species in a defined area, particularly at large spatial scales, or where birds occur at very low densities. Often it may be appropriate to consider the proportion of area occupied by the species as an alternative state variable. However, as with abundance estimation, issues of detectability must be taken into account in order to make accurate inferences: the non-detection of the species does not imply the species is genuinely absent. Here we review some recent modelling developments that permit unbiased estimation of the proportion of area occupied, colonization and local extinction probabilities. These methods allow for unequal sampling effort and enable covariate information on sampling locations to be incorporated. We also describe how these models could be extended to incorporate information from marked individuals, which would enable finer questions of population dynamics (such as turnover rate of nest sites by specific breeding pairs to be addressed. We believe these models may be applicable to a wide range of bird species and may be useful for investigating various questions of ecological interest. For example, with respect to habitat quality, we might predict that a species is more likely to have higher local extinction probabilities, or higher turnover rates of specific breeding pairs, in poor quality habitats.

  5. Oxygen Abundance Measurements of SHIELD Galaxies

    CERN Document Server

    Haurberg, Nathalie C; Cannon, John M; Marshall, Melissa V

    2015-01-01

    We have derived oxygen abundances for 8 galaxies from the Survey of HI in Extremely Low-mass Dwarfs (SHIELD). The SHIELD survey is an ongoing study of very low-mass galaxies, with M$_{\\rm HI}$ between 10$^{6.5}$ and 10$^{7.5}$ M$_{\\odot}$, that were detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. H$\\alpha$ images from the WIYN 3.5m telescope show that these 8 SHIELD galaxies each possess one or two active star-forming regions which were targeted with long-slit spectral observations using the Mayall 4m telescope at KPNO. We obtained a direct measurement of the electron temperature by detection of the weak [O III] $\\lambda$4363 line in 2 of the HII regions. Oxygen abundances for the other HII regions were estimated using a strong-line method. When the SHIELD galaxies are plotted on a B-band luminosity-metallicity diagram they appear to suggest a slightly shallower slope to the relationship than normally seen. However, that offset is systematically reduced when the near-infrared luminosity is used ins...

  6. A high-efficiency superhydrophobic plasma separator.

    Science.gov (United States)

    Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M; Yang, Shu; Bau, Haim H

    2016-02-01

    To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device's superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a "blood in-plasma out" capability, consistently extracting 65 ± 21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of >84.5 ± 25.8%. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method.

  7. Solar Flare Element Abundances from the Solar Assembly for X-rays (SAX) on MESSENGER

    CERN Document Server

    Dennis, B R; Schwartz, R A; Tolbert, A K; Starr, R D; Nittler, L R

    2015-01-01

    X-ray spectra in the range $1.5-8.5$~keV have been analyzed for 526 large flares detected with the Solar Assembly for X-rays (SAX) on the Mercury {\\em MESSENGER} spacecraft between 2007 and 2013. For each flare, the temperature and emission measure of the emitting plasma were determined from the spectrum of the continuum. In addition, with the SAX energy resolution of 0.6 keV (FWHM) at 6~keV, the intensities of the clearly resolved Fe-line complex at 6.7~keV and the Ca-line complex at 3.9~keV were determined, along with those of unresolved line complexes from S, Si, and Ar at lower energies. Comparisons of these line intensities with theoretical spectra allow the abundances of these elements relative to hydrogen to be derived, with uncertainties due to instrument calibration and the unknown temperature distribution of the emitting plasma. While significant deviations are found for the abundances of Fe and Ca from flare to flare, the abundances averaged over all flares are found to be enhanced over photospheri...

  8. Redox regulation of protein damage in plasma.

    Science.gov (United States)

    Griffiths, Helen R; Dias, Irundika H K; Willetts, Rachel S; Devitt, Andrew

    2014-01-01

    The presence and concentrations of modified proteins circulating in plasma depend on rates of protein synthesis, modification and clearance. In early studies, the proteins most frequently analysed for damage were those which were more abundant in plasma (e.g. albumin and immunoglobulins) which exist at up to 10 orders of magnitude higher concentrations than other plasma proteins e.g. cytokines. However, advances in analytical techniques using mass spectrometry and immuno-affinity purification methods, have facilitated analysis of less abundant, modified proteins and the nature of modifications at specific sites is now being characterised. The damaging reactive species that cause protein modifications in plasma principally arise from reactive oxygen species (ROS) produced by NADPH oxidases (NOX), nitric oxide synthases (NOS) and oxygenase activities; reactive nitrogen species (RNS) from myeloperoxidase (MPO) and NOS activities; and hypochlorous acid from MPO. Secondary damage to proteins may be caused by oxidized lipids and glucose autooxidation. In this review, we focus on redox regulatory control of those enzymes and processes which control protein maturation during synthesis, produce reactive species, repair and remove damaged plasma proteins. We have highlighted the potential for alterations in the extracellular redox compartment to regulate intracellular redox state and, conversely, for intracellular oxidative stress to alter the cellular secretome and composition of extracellular vesicles. Through secreted, redox-active regulatory molecules, changes in redox state may be transmitted to distant sites.

  9. An Update of the Primordial Helium Abundance

    Science.gov (United States)

    Peimbert, Antonio; Peimbert, Manuel; Luridiana, Valentina

    2015-08-01

    Three of the best determinations of the primordial helium abundance (Yp) are those obtained from low metallicity HII regions by Aver, Olive, Porter, & Skillman (2013); Izotov, Thuan, & Guseva (2014); and Peimbert, Peimbert, & Luridiana (2007). In this poster we update the Yp determination by Peimbert et al. taking into account, among other aspects, recent advances in the determination of the He atomic physical parameters, the temperature structure, the collisional effects of high temperatures on the Balmer lines, as well as the effect of H and He bound-bound absorption.We compare our results with those of Aver et al. and Izotov et al. and point out possible explanations for the differences among the three determinations. We also compare our results with those obtained with the Plank satellite considering recent measurements of the neutron mean life; this comparison has implications on the determination of the number of light neutrino families.

  10. Nitrous Oxide Production by Abundant Benthic Macrofauna

    DEFF Research Database (Denmark)

    Stief, Peter; Schramm, Andreas

    Detritivorous macrofauna species co-ingest large quantities of microorganisms some of which survive the gut passage. Denitrifying bacteria, in particular, become metabolically induced by anoxic conditions, nitrate, and labile organic compounds in the gut of invertebrates. A striking consequence...... of the short-term metabolic induction of gut denitrification is the preferential production of nitrous oxide rather than dinitrogen. On a large scale, gut denitrification in, for instance, Chironomus plumosus larvae can increase the overall nitrous oxide emission of lake sediment by a factor of eight. We...... that do not ingest large quantities of microorganisms produced insignificant amounts of nitrous oxide. Ephemera danica, a very abundant mayfly larva, was monitored monthly in a nitrate-polluted stream. Nitrous oxide production by this filter-feeder was highly dependent on nitrate availability...

  11. New Elemental Abundances for V1974 Cygni

    CERN Document Server

    Vanlandingham, K M; Shore, S N; Starrfield, S; Wagner, R M

    2005-01-01

    We present a new analysis of existing optical and ultraviolet spectra of the ONeMg nova V1974 Cygni 1992. Using these data and the photoionization code Cloudy, we have determined the physical parameters and elemental abundances for this nova. Many of the previous studies of this nova have made use of incorrect analyses and hence a new study was required. Our results show that the ejecta are enhanced, relative to solar, in helium, nitrogen, oxygen, neon, magnesium and iron. Carbon was found to be subsolar. We find an ejected mass of ~2x10e-4 solar masses. Our model results fit well with observations taken at IR, radio, sub-millimeter and X-ray wavelengths.

  12. Forms and genesis of species abundance distributions

    Directory of Open Access Journals (Sweden)

    Evans O. Ochiaga

    2015-12-01

    Full Text Available Species abundance distribution (SAD is one of the most important metrics in community ecology. SAD curves take a hollow or hyperbolic shape in a histogram plot with many rare species and only a few common species. In general, the shape of SAD is largely log-normally distributed, although the mechanism behind this particular SAD shape still remains elusive. Here, we aim to review four major parametric forms of SAD and three contending mechanisms that could potentially explain this highly skewed form of SAD. The parametric forms reviewed here include log series, negative binomial, lognormal and geometric distributions. The mechanisms reviewed here include the maximum entropy theory of ecology, neutral theory and the theory of proportionate effect.

  13. VLT/UVES abundances in four nearby dwarf spheroidal galaxies. I. Nucleosynthesis and abundance ratios

    NARCIS (Netherlands)

    Shetrone, M; Venn, KA; Tolstoy, E; Primas, F; Hill, [No Value; Kaufer, A

    2003-01-01

    We have used the Ultraviolet Echelle Spectrograph (UVES) on Kueyen (UT2) of the Very Large Telescope to take spectra of 15 individual red giants in the Sculptor, Fornax, Carina, and Leo I dwarf spheroidal galaxies (dSph's). We measure the abundances of alpha-, iron peak, first s-process, second s-pr

  14. Abundances of Galactic Anticenter Planetary Nebulae and the Oxygen Abundance Gradient in the Galactic Disk

    CERN Document Server

    Henry, R B C; Jaskot, Anne E; Balick, Bruce; Morrison, Michael A; Milingo, Jacquelynne B

    2010-01-01

    We have obtained spectrophotometric observations of 41 anticenter planetary nebulae (PNe) located in the disk of the Milky Way. Electron temperatures and densities, as well as chemical abundances for He, N, O, Ne, S, Cl, and Ar were determined. Incorporating these results into our existing database of PN abundances yielded a sample of 124 well-observed objects with homogeneously-determined abundances extending from 0.9-21 kpc in galactocentric distance. We performed a detailed regression analysis which accounted for uncertainties in both oxygen abundances and radial distances in order to establish the metallicity gradient across the disk to be: 12+log(O/H)=(9.09+/-.05) - (0.058+/-.006) x Rg, with Rg in kpc. While we see some evidence that the gradient steepens at large galactocentric distances, more objects toward the anticenter need to be observed in order to confidently establish the true form of the metallicity gradient. We find no compelling evidence that the gradient differs between Peimbert Types I and ...

  15. Solar-system abundances of the elements - A new table

    Science.gov (United States)

    Grevesse, Nicolas; Anders, Edward

    1989-01-01

    This paper presents an abridged version of a new abundance compilation (Anders and Grevesse, 1988), representing an update of Anders and Ebihara (1982) and Grevesse (1984). It includes revised meteoritic abundances as well as photospheric and coronal abundances, based on literature through mid-1988.

  16. Variations in lead isotopic abundances in Sprague-Dawley rat tissues: possible reason of formation.

    Directory of Open Access Journals (Sweden)

    Duojian Liu

    Full Text Available It has been reported in previous research that the lead isotopic composition of blood, urine and feces samples statistically differed from the given lead sources in Sprague-Dawley (SD rats. However, the reason for this phenomenon is still unclear. An animal experiment was performed to investigate the lead isotope fractionation in diverse biological samples (i.e., lungs, liver, kidneys, bone and to explore the possible reasons. SD rats were intratracheally instilled with lead acetate at the concentrations of 0, 0.02, 0.2, and 2 mg/kg body weight. Biological samples were collected for lead isotope analysis using an inductively coupled plasma mass spectrometry (ICP-MS. Significant differences are observed in lead isotope abundances among the diverse biological samples. The lead isotope abundances ((206Pb, (207Pb and (208Pb in diverse biological samples show different degrees and directions of departure from the given lead source. The results suggest that differences in enrichment or depletion capacity for each lead isotope in the various tissues might lead to the variation in lead isotopic abundances in tissues. Moreover, a nonlinear relationship between the blood lead level and the lead isotope abundances in liver and bone is observed. When the whole-blood level is higher than 50 ng/mL, the lead isotopic compositions of biological samples tend to be the same. Thus, the data support the speculation of a fractionation functional threshold.

  17. Plasma Free Metanephrines

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  18. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  19. Plasma physics and fusion plasma electrodynamics

    CERN Document Server

    Bers, Abraham

    2016-01-01

    Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

  20. Abundance of sardine fish species in Bangladesh

    Directory of Open Access Journals (Sweden)

    Roy Bikram Jit

    2012-06-01

    Full Text Available The study was conducted during January, 2012 to December 2012 in the sardine fisheries which is occurred both in artisanal and industrial fishing sector in the marine water of the Bay of Bengal of Bangladesh region. During this study period the total landing amounts by weight of sardines were 7352.99 MT, among these 23.76% (1747.22 MT was exploited by the artisanal mechanized boats and 76.24% (5605.77 MT captured through different industrial fishing trawlers and contributed 17.51% of the total marine fish production by commercial fish trawlers during the study period. 4 sardine species have been recorded from our marine territory. Among them, 2 sardine species are highly abundant, Sardinella fimbriata total production volumes was 5495.79 MT (74.74% contributed 1747.22MT (31.79% from the artisanal and 3748.57MT (68.21% from the industrial sector and Dussumieria acuta production amounts was 1857.20MT (25.26% contributed only from the industrial fishing sector.Species wise contribution shows that S. fimbriata contributed 100% in the artisanal sector and in the industrial fishing S. fimbriata contributed 66.87% and D. acuta contributed the rest 33.13%. The distribution of the S. fimbriata is within 10-20 meters depth and abundance was observed in the southern part of the South patches and South of south patches (N: 210.09// -22, E: 920.04/-07 to N: 200.45/-25, E: 920.18/-56 and 10-50m depth in onshore and off shore areas in the north-west to north-east of Middle ground (Kohinoor point -N: 210.36/.23, E: 900.06/.43 to N: 210.18/.18, E 910.17/.57. The distribution of the D. acuta is within 40-60 m. depth and abundance was observed in the north-west to north-east of Middle ground areas (Kohinoor point - N: 210.36/.23, E: 900.06/.43 to N: 210.18/.18, E 910.17/.57 and south-west to south-east of Middle ground (Kohinoor point- N: 200-17/.29, E: 900.15/.21 to N: 200.29/.56, E: 910.24/.22 in the Bay of Bengal of Bangladesh region. The peak capture season of

  1. Regulation of NHE3, NKCC2, and NCC abundance in kidney during aldosterone escape phenomenon: role of NO.

    Science.gov (United States)

    Turban, Sharon; Wang, Xiao-Yan; Knepper, Mark A

    2003-11-01

    Escape from aldosterone-induced renal NaCl retention is an important homeostatic mechanism in pathophysiological states in which plasma aldosterone levels are inappropriately elevated, e.g., in primary aldosteronism. Our previous studies demonstrated that the escape process occurs largely as a result of a marked suppression of the abundance of the thiazide-sensitive Na-Cl cotransporter (NCC) of the distal convoluted tubule but have also demonstrated a paradoxical increase in the protein abundance of the apical Na/H exchanger of the proximal tubule (NHE3). In the present study, we confirmed the increase in NHE3 and also showed that a similar increase in NHE3 protein abundance occurs in escape from ANG II-mediated NaCl retention. To investigate the potential role of nitric oxide (NO) in the observed upregulation of NHE3, we repeated the aldosterone escape experiment with a superimposed infusion of a NO synthase inhibitor, NG-nitro-l-arginine methyl ester (l-NAME). l-NAME infusion abolished the increase in NHE3 protein abundance. Furthermore, in a different experiment, NO synthase inhibition uncovered an associated decrease in the abundance of the Na-K-2Cl cotransporter (NKCC2) of the thick ascending limb, not seen with simple aldosterone escape. However, NO synthase inhibition did not block the decrease in NCC abundance normally seen with aldosterone escape. Furthermore, l-NAME infusion in aldosterone-treated rats markedly decreased both NHE3 and NKCC2 protein abundance, without changes in the corresponding mRNA levels. We conclude that NHE3 and NKCC2 protein abundances in kidney are positively regulated by NO and that the increase in NHE3 abundance seen in the aldosterone escape phenomenon is NO dependent.

  2. Manganese abundances in Galactic bulge red giants

    Science.gov (United States)

    Barbuy, B.; Hill, V.; Zoccali, M.; Minniti, D.; Renzini, A.; Ortolani, S.; Gómez, A.; Trevisan, M.; Dutra, N.

    2013-11-01

    Context. Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut between the matter ejected and falling back onto the remnant, electron and neutron excesses, mixing fallback, and explosion energy. Manganese is also produced in type Ia SNe. Aims: The aim of this work is the study of abundances of the iron-peak element Mn in 56 bulge giants, among which 13 are red clump stars. Four bulge fields along the minor axis are inspected. The study of abundances of Mn-over-Fe as a function of metallicity in the Galactic bulge may shed light on its production mechanisms. Methods: High-resolution spectra were obtained using the FLAMES+UVES spectrograph on the Very Large Telescope. The spectra were obtained within a program to observe 800 stars using the GIRAFFE spectrograph, together with the present UVES spectra. Results: We aim at identifying the chemical evolution of manganese, as a function of metallicity, in the Galactic bulge. We find [Mn/Fe] ~ -0.7 at [Fe/H] ~ -1.3, increasing to a solar value at metallicities close to solar, and showing a spread around - 0.7 ≲ [Fe/H] ≲ -0.2, in good agreement with other work on Mn in bulge stars. There is also good agreement with chemical evolution models. We find no clear difference in the behaviour of the four bulge fields. Whereas [Mn/Fe] vs. [Fe/H] could be identified with the behaviour of the thick disc stars, [Mn/O] vs. [O/H] has a behaviour running parallel, at higher metallicities, compared to thick disc stars, indicating that the bulge enrichment might have proceeded differently from that of the thick disc. Observations collected at the European Southern Observatory, Paranal, Chile (ESO programmes 71.B-0617A, 73.B0074A, and GTO 71.B-0196).Tables 1-6 and Figs. 1-6 are available in electronic form at http://www.aanda.org

  3. Abundances in the Ejecta of Core Collapse Supernova Remnants, G350.1-0.3 and G349.7+0.2

    CERN Document Server

    Yasumi, Masato; Nakashima, Shinya; Uchida, Hiroyuki; Sugawara, Ryusuke; Tsuru, Takeshi Go; Tanaka, Takaaki; Koyama, Katsuji

    2014-01-01

    We present Suzaku results of the two Galactic supernova remnants (SNRs), G350.1-0.3 and G349.7+0.2. We find Al and Ni K alpha lines from both the SNRs for the first time, in addition to previously detected K-shell lines of Mg, Si, S, Ar, Ca and Fe. The spectra are well described by two optically thin thermal plasmas: a low-temperature (low-kT) plasma in collisional ionization equilibrium and a high-temperature (high-kT) plasma in non-equilibrium ionization. Since the low-kT plasma has solar metal abundances, it is thought to be of interstellar medium origin. The high-kT plasma has super-solar abundances, hence it is likely to be of ejecta origin. The abundance patterns of the ejecta components are similar to those of core-collapse supernovae with the progenitor mass of ~15-25 M_solar for G350.1-0.3 and ~35-40 M_solar for G349.7+0.2. We find extremely high abundances of Ni compared to Fe (Z_Ni/Z_Fe ~8). Based on the measured column densities between the SNRs and the near sky background, we propose that G350.1-...

  4. Determination of solar wind elemental abundances from M/Q observations during three periods in 1980

    Science.gov (United States)

    Kunz, S.; Bochsler, P.; Geiss, J.; Ogilvie, K. W.; Coplan, M. A.

    1983-10-01

    Mass spectra in the range 2 ≤ M/Q ≤ 3 provided by a high resolution mode of the ISEE-3 Plasma Composition Experiment were evaluated for three selected periods during early 1980. The observed Ne/O ratios are compatible with estimated solar abundance ratios. In two of the three periods, the He/Ne-ratios agree with the Apollo foil results. Freezing-in temperatures for oxygen are similar to those obtained by other groups. Possible reasons for an unexpectedly high flux at M/Q = 2.4 are discussed.

  5. Determination of solar wind elemental abundances from M/Q observations during three periods in 1980

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, S.; Bochsler, P.; Geiss, J. (Bern Univ. (Switzerland). Physikalisches Inst.); Ogilvie, K.W. (National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center); Coplan, M.A. (Maryland Univ., College Park (USA). Inst. for Physical Science and Technology)

    1983-10-01

    Mass spectra in the range 2<=M/Q<=3 provided by a high resolution mode of the ISEE-3 Plasma Composition Experiment were evaluated for three selected periods during early 1980. The observed Ne/O ratios are compatible with estimated solar abundance ratios. In two of the three periods, the He/Ne-ratios agree with the Apollo foil results. Freezing-in temperatures for oxygen are similar to those obtained by other groups. Possible reasons for an unexpectedly high flux at M/Q=2.4 are discussed.

  6. Gravitationally induced particle production and its impact on the WIMP abundance

    Energy Technology Data Exchange (ETDEWEB)

    Baranov, I., E-mail: iuribaranov@usp.br [Departamento de Física Geral, Universidade de São Paulo, 05508-090 São Paulo, SP (Brazil); Lima, J.A.S., E-mail: limajas@astro.iag.usp.br [Departamento de Astronomia, Universidade de São Paulo, 05508-900 São Paulo, SP (Brazil); Programa de Pós-Graduação em Física, Universidade Federal do Pará, 66075-110 Belém, Pará (Brazil)

    2015-12-17

    A large set of independent astronomical observations have provided a strong evidence for nonbaryonic dark matter in the Universe. One of the most investigated candidates is an unknown long-lived Weakly Interacting Massive Particle (WIMP) which was in thermal equilibrium with the primeval plasma. Here we investigate the WIMP abundance based on the relativistic kinetic treatment for gravitationally induced particle production recently proposed in the literature (Lima and Baranov, 2014) [16]. The new evolution equation is deduced and solved both numerically and through a semi-analytical approach. The predictions of the WIMP observables are discussed and compared with the ones obtained in the standard approach.

  7. Gravitationally induced particle production and its impact on the WIMP abundance

    Directory of Open Access Journals (Sweden)

    I. Baranov

    2015-12-01

    Full Text Available A large set of independent astronomical observations have provided a strong evidence for nonbaryonic dark matter in the Universe. One of the most investigated candidates is an unknown long-lived Weakly Interacting Massive Particle (WIMP which was in thermal equilibrium with the primeval plasma. Here we investigate the WIMP abundance based on the relativistic kinetic treatment for gravitationally induced particle production recently proposed in the literature (Lima and Baranov, 2014 [16]. The new evolution equation is deduced and solved both numerically and through a semi-analytical approach. The predictions of the WIMP observables are discussed and compared with the ones obtained in the standard approach.

  8. Gravitationally Induced Particle Production and its Impact on the WIMP Abundance

    CERN Document Server

    Baranov, I

    2015-01-01

    A large set of independent astronomical observations have provided a strong evidence for nonbaryonic dark matter in the Universe. One of the most investigated candidates is an unknown long-lived Weakly Interacting Massive Particle (WIMP) which was in thermal equilibrium with the primeval plasma. Here we investigate the WIMP abundance based on the relativistic kinetic treatment for gravitationally induced particle production recently proposed in the literature (Lima \\& Baranov, Phys. Rev. D {\\bf 90}, 043515, 2014). The new evolution equation is deduced and solved both numerically and also through a semi-analytical approach. The predictions of the WIMP observables are discussed and compared with the ones obtained in the standard approach.

  9. IgG4-Related Disease without Overexpression of IgG4: Pathogenesis Implications

    Directory of Open Access Journals (Sweden)

    Naoshi Nishina

    2012-01-01

    Full Text Available IgG4-related disease is a new disease group that affects multiple organs. It is characterized by high serum IgG4 and abundant infiltration of IgG4-bearing plasma cells in the affected organ. Here, we describe an intriguing case that suggested that IgG4-related disease might present without IgG4 overexpression or infiltration, at least during a relapse. A 47-year-old man had been diagnosed with systemic lupus erythematosus 15 years. He was admitted due to a pituitary mass, systemic lymphadenopathy, and multiple nodules in the lungs and kidneys. The serum IgG4 level was normal and histopathological examination of the pituitary mass showed abundant lymphocyte and plasma cell infiltration with very few IgG4-positive cells. When we examined specimens preserved from 15 years ago, we found high serum IgG4 levels and IgG4-bearing plasma cell infiltration. This resulted in a diagnosis of IgG4-related disease, and we considered the current episode to be a relapse without IgG4 overexpression. This case indicated that, to clarify the pathogenesis of IgG4-related disease, current cases should repeat specimen evaluations over the course of IgG4-related disease to define diagnostic markers.

  10. Impact of climate variation on mosquito abundance in California.

    Science.gov (United States)

    Reisen, William K; Cayan, Daniel; Tyree, Mary; Barker, Christopher M; Eldridge, Bruce; Dettinger, Michael

    2008-06-01

    Temporal variation in the abundance of the encephalitis virus vector mosquito, Culex tarsalis Coquillet, was linked significantly with coincident and antecedent measures of regional climate, including temperature, precipitation, snow pack, and the El Niño/Southern Oscillation anomaly. Although variable among traps, historical records that spanned two to five decades revealed climate influences on spring and summer mosquito abundance as early as the previous fall through early summer. Correlations between winter and spring precipitation and snow pack and spring Cx. tarsalis abundance were stronger than correlations with summer abundance. Spring abundance was also correlated positively with winter and spring temperature, whereas summer abundance correlated negatively with spring temperature and not significantly with summer temperature. Correlations with antecedent climate provide the opportunity to forecast vector abundance and therefore encephalitis virus risk, a capability useful in intervention decision support systems at local and state levels.

  11. The Solar Heavy Element Abundances: I. Constraints from Stellar Interiors

    CERN Document Server

    Delahaye, F; Delahaye, Franck; Pinsonneault, Marc

    2005-01-01

    The latest solar atmosphere models include non-LTE corrections and 3D hydrodynamic convection simulations. These models predict a significant reduction in the solar metal abundance, which leads to a serious conflict between helioseismic data and the predictions of solar interiors models. We demonstrate that the helioseismic constraints on the surface convection zone depth and helium abundance combined with stellar interiors models can be used to define the goodness of fit for a given chemical composition. After a detailed examination of the errors in the theoretical models we conclude that models constructed with the older solar abundances are consistent (<2 \\sigma) with the seismic data. Models constructed with the proposed new low abundance scale are strongly disfavored, disagreeing at the 15 \\sigma level. We then use the sensitivity of the seismic properties to abundance changes to invert the problem and infer a seismic solar heavy element abundance mix with two components: meteoritic abundances, and th...

  12. Protein abundance profiling of the Escherichia coli cytosol

    DEFF Research Database (Denmark)

    Ishihama, Y.; Schmidt, T.; Rappsilber, J.

    2008-01-01

    PAI approach which takes into account the number of sequenced peptides per protein. The values of abundance are within a broad range and accurately reflect independently measured copy numbers per cell. As expected, the most abundant proteins were those involved in protein synthesis, most notably ribosomal...... sample. Using a combination of LC-MS/MS approaches with protein and peptide fractionation steps we identified 1103 proteins from the cytosolic fraction of the Escherichia coli strain MC4100. A measure of abundance is presented for each of the identified proteins, based on the recently developed em...... protein and mRNA abundance in E. coli cells. Conclusion: Abundance measurements for more than 1000 E. coli proteins presented in this work represent the most complete study of protein abundance in a bacterial cell so far. We show significant associations between the abundance of a protein and its...

  13. Nucleosynthesis: Stellar and Solar Abundances and Atomic Data

    CERN Document Server

    Cowan, J J; Sneden, C; Den Hartog, E A; Collier, J L; Cowan, John J.; Lawler, James E.; Sneden, Christopher; Collier, Jason

    2006-01-01

    Abundance observations indicate the presence of often surprisingly large amounts of neutron capture (i.e., s- and r-process) elements in old Galactic halo and globular cluster stars. These observations provide insight into the nature of the earliest generations of stars in the Galaxy -- the progenitors of the halo stars -- responsible for neutron-capture synthesis. Comparisons of abundance trends can be used to understand the chemical evolution of the Galaxy and the nature of heavy element nucleosynthesis. In addition age determinations, based upon long-lived radioactive nuclei abundances, can now be obtained. These stellar abundance determinations depend critically upon atomic data. Improved laboratory transition probabilities have been recently obtained for a number of elements. These new gf values have been used to greatly refine the abundances of neutron-capture elemental abundances in the solar photosphere and in very metal-poor Galactic halo stars. The newly determined stellar abundances are surprisingl...

  14. Proteomics characterization of abundant Golgi membrane proteins.

    Science.gov (United States)

    Bell, A W; Ward, M A; Blackstock, W P; Freeman, H N; Choudhary, J S; Lewis, A P; Chotai, D; Fazel, A; Gushue, J N; Paiement, J; Palcy, S; Chevet, E; Lafrenière-Roula, M; Solari, R; Thomas, D Y; Rowley, A; Bergeron, J J

    2001-02-16

    A mass spectrometric analysis of proteins partitioning into Triton X-114 from purified hepatic Golgi apparatus (84% purity by morphometry, 122-fold enrichment over the homogenate for the Golgi marker galactosyl transferase) led to the unambiguous identification of 81 proteins including a novel Golgi-associated protein of 34 kDa (GPP34). The membrane protein complement was resolved by SDS-polyacrylamide gel electrophoresis and subjected to a hierarchical approach using delayed extraction matrix-assisted laser desorption ionization mass spectrometry characterization by peptide mass fingerprinting, tandem mass spectrometry to generate sequence tags, and Edman sequencing of proteins. Major membrane proteins corresponded to known Golgi residents, a Golgi lectin, anterograde cargo, and an abundance of trafficking proteins including KDEL receptors, p24 family members, SNAREs, Rabs, a single ARF-guanine nucleotide exchange factor, and two SCAMPs. Analytical fractionation and gold immunolabeling of proteins in the purified Golgi fraction were used to assess the intra-Golgi and total cellular distribution of GPP34, two SNAREs, SCAMPs, and the trafficking proteins GBF1, BAP31, and alpha(2)P24 identified by the proteomics approach as well as the endoplasmic reticulum contaminant calnexin. Although GPP34 has never previously been identified as a protein, the localization of GPP34 to the Golgi complex, the conservation of GPP34 from yeast to humans, and the cytosolically exposed location of GPP34 predict a role for a novel coat protein in Golgi trafficking.

  15. Nitrogen Abundances in High-z DLAs

    CERN Document Server

    Molaro, P; D'Odorico, V; Péroux, C

    2003-01-01

    Determination of chemical abundances for elements produced mainly by Type I SNae and intermediate mass stars in high redshift DLAs probes the early chemical build-up on time-scales comparable with their production. Nitrogen shows a peculiar behaviour never detected before in any other class of objects. For [N/H] < -3 there is a plateau with [N/Si]= -1.45(\\pm 0.05). We interpret this as empirical evidence for primary N production by massive stars in young systems where AGB stars have not yet had time to make their contribution. The plateau provides the observational integrated yields for N production by massive stars which are theoretically rather uncertain. High N/Si and solar [alpha/iron-peak] ratios are observed at high redshift and place at an earlier epoch the onset of star formation. On the other hand, low N/Si, i.e. young objects, are observed also at relatively low redshifts. These evidences suggest that DLAs started to be formed at a very early epoch but their formation has been extended up to late...

  16. Quasar Elemental Abundances at High Redshifts

    DEFF Research Database (Denmark)

    Dietrich, M.; Hamann, F.; Shields, J. C.

    2003-01-01

    We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estimate the epoch of first star formation. The fluxes of several ultraviolet emission lines were investigated within...... the framework of the most recent photoionization models to estimate the metallicity of the gas associated with the high-z quasars. Standard photoionization parameters and the assumption of secondary nitrogen enrichment indicate an average abundance of Z/Z_sol = 4 to 5 in the line emitting gas. Assuming a time...... scale of t_evol = 0.5 - 0.8 Gyrs for the chemical enrichment of the gas, the first major star formation for quasars with z>=4 should have started at a redshift of z_f = 6 - 8, corresponding to an age of the universe of several 10^8 yrs (H_o = 65 km/s/Mpc, Omega_M = 0.3, Omega_Lambda = 0.7). We note...

  17. Quasar Elemental Abundances at High Redshifts

    CERN Document Server

    Dietrich, M; Shields, J C; Constantin, A; Heidt, J; Jäger, K; Vestergaard, M; Wagner, S J

    2003-01-01

    We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estimate the epoch of first star formation. The fluxes of several ultraviolet emission lines were investigated within the framework of the most recent photoionization models to estimate the metallicity of the gas associated with the high-z quasars. Standard photoionization parameters and the assumption of secondary nitrogen enrichment indicate an average abundance of Z/Z_sol = 4 to 5 in the line emitting gas. Assuming a time scale of t_evol = 0.5 - 0.8 Gyrs for the chemical enrichment of the gas, the first major star formation for quasars with z>=4 should have started at a redshift of z_f = 6 - 8, corresponding to an age of the universe of several 10^8 yrs (H_o = 65 km/s/Mpc, Omega_M = 0.3, Omega_Lambda = 0.7). We note that this also appears to be the era of re-ionization of the universe. Finally, there is some evidence for a positive lum...

  18. Comparing halo bias from abundance and clustering

    CERN Document Server

    Hoffmann, Kai; Gaztanaga, Enrique

    2015-01-01

    We model the abundance of haloes in the $\\sim(3 \\ \\text{Gpc}/h)^3$ volume of the MICE Grand Challenge simulation by fitting the universal mass function with an improved Jack-Knife error covariance estimator that matches theory predictions. We present unifying relations between different fitting models and new predictions for linear ($b_1$) and non-linear ($c_2$ and $c_3$) halo clustering bias. Different mass function fits show strong variations in their overall poor performance when including the low mass range ($M_h \\lesssim 3 \\ 10^{12} \\ M_{\\odot}/h$) in the analysis, which indicates noisy friends-of-friends halo detection given the MICE resolution ($m_p \\simeq 3 \\ 10^{10} \\ M_{\\odot}$/h). Together with fits from the literature we find an overall variance in the amplitudes of around $10%$ in the low mass and up to $50%$ in the high mass (galaxy cluster) range ($M_h > 10^{14} \\ M_{\\odot}/h$). These variations propagate into a $10%$ change in $b_1$ predictions and a $50%$ change in $c_2$ or $c_3$. Despite the...

  19. Late Embryogenesis Abundant (LEA proteins in legumes

    Directory of Open Access Journals (Sweden)

    Marina eBattaglia

    2013-06-01

    Full Text Available Plants are exposed to different external conditions that affect growth, development, and productivity. Water deficit is one of these adverse conditions caused by drought, salinity, and extreme temperatures. Plants have developed different responses to prevent, ameliorate or repair the damage inflicted by these stressful environments. One of these responses is the activation of a set of genes encoding a group of hydrophilic proteins that typically accumulate to high levels during seed dehydration, at the last stage of embryogenesis, hence named Late Embryogenesis Abundant (LEA proteins. LEA proteins also accumulate in response to water limitation in vegetative tissues, and have been classified in seven groups based on their amino acid sequence similarity and on the presence of distinctive conserved motifs. These proteins are widely distributed in the plant kingdom, from ferns to angiosperms, suggesting a relevant role in the plant response to this unfavorable environmental condition. In this review, we analyzed the LEA proteins from those legumes whose complete genomes have been sequenced such as Phaseolus vulgaris, Glycine max, Medicago truncatula, Lotus japonicus, Cajanus cajan and Cicer arietinum. Considering their distinctive motifs, LEA proteins from the different groups were identified, and their sequence analysis allowed the recognition of novel legume specific motifs. Moreover, we compile their transcript accumulation patterns based on publicly available data. In spite of the limited information on these proteins in legumes, the analysis and data compiled here confirms the high correlation between their accumulation and water deficit, reinforcing their functional relevance under this detrimental conditions.

  20. Dielectrophoretic capture of low abundance cell population using thick electrodes

    Science.gov (United States)

    Marchalot, Julien; Chateaux, Jean-François; Faivre, Magalie; Mertani, Hichem C.; Ferrigno, Rosaria; Deman, Anne-Laure

    2015-01-01

    Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force (FDEP) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10). PMID:26392836

  1. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  2. Incubation of human blood fractions leads to changes in apparent miRNA abundance

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Jørgensen, Stine Thuen; Heegaard, Peter M. H.

    A basic investigation on the presence and composition of miRNA species and their reaction to in vitro incubation and stimulation (borosilicate glass beads), in plasma, platelet-rich plasma (PRP), red blood cells (RBC), peripheral blood mononuclear cells (PBMC) and polymorphonuclear (PMN) cells...... in significant changes in the abundance of miR-21, miR-155, Let-7c and Let 7f in plasma, miR-21, miR-23a and miR-150 in RBC and miR-15b, miR-126, miR155 and Let-7g in PBMC, while no change was seen in PRP and PMN. Interestingly, in the samples incubated with glass beads, no miRNAs were significantly affected...... in plasma, RBC, PBMC and PMN, while expression of miR-25, miR15a, miR-126 and miR223 was significantly changed in PRP. Thus, PRP, as the only blood fraction depended on stimulation to change its miRNA profile upon incubation. For the other fractions, stimulation either leveled out the changes induced...

  3. International movement of plasma and plasma contracting.

    Science.gov (United States)

    Farrugia, A

    2005-01-01

    Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined.

  4. Communication through Plasma Sheaths

    CERN Document Server

    Korotkevich, A O; Zakharov, V E

    2007-01-01

    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.

  5. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  6. Effects of short-chain fatty acid-supplemented total parenteral nutrition on intestinal pro-inflammatory cytokine abundance.

    Science.gov (United States)

    Milo, L A; Reardon, K A; Tappenden, K A

    2002-09-01

    We examined the effect of short-chain fatty acid-supplemented total parenteral nutrition on proinflammatory cytokine levels in piglets. Piglets (N = 22) received either standard total parenteral nutrition or total parenteral nutrition supplemented with short-chain fatty acids. After seven days of continuous nutrient infusion, proinflammatory cytokine (TNF-alpha, IL-1beta, IL-6) abundance in plasma, jejunal, and ileal samples and small intestinal myeloperoxidase was determined using western blotting. No differences were seen in TNF-alpha small intestinal abundance. IL-1beta was higher in the small intestine of the short-chain fatty acid group (P short-chain fatty acids beneficially increase small intestinal abundance of IL-1beta and IL-6 during total parenteral nutrition administration, while not affecting systemic production of these cytokines or intestinal inflammation.

  7. Radial molecular abundances and gas cooling in starless cores

    CERN Document Server

    Sipilä, O

    2012-01-01

    Aims: We aim to simulate radial profiles of molecular abundances and the gas temperature in cold and heavily shielded starless cores by combining chemical and radiative transfer models. Methods: A determination of the dust temperature in a modified Bonnor-Ebert sphere is used to calculate initial radial molecular abundance profiles. The abundances of selected cooling molecules corresponding to two different core ages are then extracted to determine the gas temperature at two time steps. The calculation is repeated in an iterative process yielding molecular abundances consistent with the gas temperature. Line emission profiles for selected substances are calculated using simulated abundance profiles. Results: The gas temperature is a function of time; the gas heats up as the core gets older because the cooling molecules are depleted onto grain surfaces. The contributions of the various cooling molecules to the total cooling power change with time. Radial chemical abundance profiles are non-trivial: different s...

  8. TEA: A Code for Calculating Thermochemical Equilibrium Abundances

    CERN Document Server

    Blecic, Jasmina; Bowman, M Oliver

    2015-01-01

    We present an open-source Thermochemical Equilibrium Abundances (TEA) code that calculates the abundances of gaseous molecular species. The code is based on the methodology of White et al. (1958) and Eriksson (1971). It applies Gibbs free-energy minimization using an iterative, Lagrangian optimization scheme. Given elemental abundances, TEA calculates molecular abundances for a particular temperature and pressure or a list of temperature-pressure pairs. We tested the code against the method of Burrows & Sharp (1999), the free thermochemical equilibrium code CEA (Chemical Equilibrium with Applications), and the example given by White et al. (1958). Using their thermodynamic data, TEA reproduces their final abundances, but with higher precision. We also applied the TEA abundance calculations to models of several hot-Jupiter exoplanets, producing expected results. TEA is written in Python in a modular format. There is a start guide, a user manual, and a code document in addition to this theory paper. TEA is ...

  9. Evolution of dispersion in the cosmic deuterium abundance

    CERN Document Server

    Dvorkin, Irina; Silk, Joseph; Petitjean, Patrick; Olive, Keith A

    2016-01-01

    Deuterium is created during Bing Bang Nucleosynthesis, and, in contrast to the other light stable nuclei, can only be destroyed thereafter by fusion in stellar interiors. In this paper we study the cosmic evolution of the deuterium abundance in the interstellar medium and its dispersion using realistic galaxy evolution models. We find that models that reproduce the observed metal abundance are compatible with observations of the deuterium abundance in the local ISM and z ~ 3 absorption line systems. In particular, we reproduce the low astration factor which we attribute to a low global star formation efficiency. We calculate the dispersion in deuterium abundance arising from different structure formation histories in different parts of the Universe. Our model also predicts an extremely tight correlation between deuterium and metal abundances which could be used to measure the primordial deuterium abundance.

  10. Shallow extra mixing in solar twins inferred from Be abundances

    CERN Document Server

    Maia, M Tucci; Castro, M; Asplund, M; Ramírez, I; Monroe, T R; Nascimento, J D do; Yong, D

    2015-01-01

    Lithium and beryllium are destroyed at different temperatures in stellar interiors. As such, their relative abundances offer excellent probes of the nature and extent of mixing processes within and below the convection zone. We determine Be abundances for a sample of eight solar twins for which Li abundances have previously been determined. The analyzed solar twins span a very wide range of age, 0.5-8.2 Gyr, which enables us to study secular evolution of Li and Be depletion. We gathered high-quality UVES/VLT spectra and obtained Be abundances by spectral synthesis of the Be II 313 nm doublet. The derived beryllium abundances exhibit no significant variation with age. The more fragile Li, however, exhibits a monotonically decreasing abundance with increasing age. Therefore, relatively shallow extra mixing below the convection zone is necessary to simultaneously account for the observed Li and Be behavior in the Sun and solar twins.

  11. Collective plasma corrections to thermonuclear reactions rates in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Tsytovich, V.N. [General Physics Institute, Moscow (Russian Federation)

    2002-01-01

    the nuclear reactions. Numerical evaluation of the plasma corrections for the nuclear reactions of the hydrogen cycle, using the parameters of the present temperature, density and abundance in the solar interior, are performed. (author)

  12. Bacterial community profiles in low microbial abundance sponges

    OpenAIRE

    Giles, Emily C; Kamke, Janine; Moitinho-Silva, Lucas; Taylor, Michael W.; Hentschel, Ute; Ravasi, Timothy; Schmitt, Susanne

    2013-01-01

    It has long been recognized that sponges differ in the abundance of associated microorganisms, and they are therefore termed either 'low microbial abundance' (LMA) or 'high microbial abundance' (HMA) sponges. Many previous studies concentrated on the dense microbial communities in HMA sponges, whereas little is known about microorganisms in LMA sponges. Here, two LMA sponges from the Red Sea, two from the Caribbean and one from the South Pacific were investigated. With up to only five bacteri...

  13. Abundances of metals in five nearby open clusters

    CERN Document Server

    Hui-Bon-Hoa, A

    1998-01-01

    Abundances of Mg, Ca, Sc, Cr, Fe, and Ni are derived for A stars of five nearby open clusters of various ages using high resolution spectroscopy. We point out a correlation between the abundance of Ca and that of Sc, suggesting that the abundance anomalies of these elements arise from the same physical process. Pronounced Am patterns are rather found in the oldest cluster stars whereas younger targets show weaker Am anomalies and atypical patterns for some of them.

  14. The metal-rich abundance pattern - spectroscopic properties and abundances for 107 main-sequence stars

    Science.gov (United States)

    Ivanyuk, O. M.; Jenkins, J. S.; Pavlenko, Ya. V.; Jones, H. R. A.; Pinfield, D. J.

    2017-07-01

    We report results from the high-resolution spectral analysis of the 107 metal-rich (mostly [Fe/H] ≥ 7.67 dex) target stars from the Calan-Hertfordshire Extrasolar Planet Search programme observed with HARPS. Using our procedure of finding the best fit to the absorption line profiles in the observed spectra, we measure the abundances of Na, Mg, Al, Si, Ca, Ti, Cr, Mn, Fe, Ni, Cu and Zn, and then compare them with known results from different authors. Most of our abundances agree with these works at the level of ±0.05 dex or better for the stars we have in common. However, we do find systematic differences that make direct inferences difficult. Our analysis suggests that the selection of line lists and atomic line data along with the adopted continuum level influence these differences the most. At the same time, we confirm the positive trends of abundances versus metallicity for Na, Mn, Ni and, to a lesser degree, Al. A slight negative trend is observed for Ca, whereas Si and Cr tend to follow iron. Our analysis allows us to determine the positively skewed normal distribution of projected rotational velocities with a maximum peaking at 3 km s-1. Finally, we obtained a Gaussian distribution of microturbulent velocities that has a maximum at 1.2 km s-1 and a full width at half-maximum Δv1/2 = 0.35 km s-1, indicating that metal-rich dwarfs and subgiants in our sample have a very restricted range in microturbulent velocity.

  15. Modelling tick abundance using machine learning techniques and satellite imagery

    DEFF Research Database (Denmark)

    Kjær, Lene Jung; Korslund, L.; Kjelland, V.

    satellite images to run Boosted Regression Tree machine learning algorithms to predict overall distribution (presence/absence of ticks) and relative tick abundance of nymphs and larvae in southern Scandinavia. For nymphs, the predicted abundance had a positive correlation with observed abundance...... the predicted distribution of larvae was mostly even throughout Denmark, it was primarily around the coastlines in Norway and Sweden. Abundance was fairly low overall except in some fragmented patches corresponding to forested habitats in the region. Machine learning techniques allow us to predict for larger...... the collected ticks for pathogens and using the same machine learning techniques to develop prevalence maps of the ScandTick region....

  16. Abundance analysis of the slow nova PW Vulpeculae 1984

    CERN Document Server

    Schwarz, G J; Shore, S N; Hauschildt, P H; Schwarz, Greg J.; Shore, Steven N.; Hauschildt, Peter H.

    1997-01-01

    We determine the elemental abundances for the ejecta of the slow nova PW Vul 1984. Our technique uses a minimization of the emission line fits of a photoionization model to available ultraviolet, optical and infrared spectra. We find the following abundances (by number) with respect to solar: He/H = 1.0 $^{+7}_{-2}$. In addition, there is weak evidence for solar Ne and Mg and twice solar Fe. Previous studies (Saizar et al. 1991 and Andreã et al. 1991, 1994) of PW Vul have yielded considerable differences in their derived elemental abundances for the ejecta. Our abundances fall in between the previous studies. To explain the discrepant abundances, we analyze in detail the data and methods used to obtain the previous results. The abundances of Saizar et al. (1991) are significantly smaller then our values because of the lower electron temperature used by Saizar et al. in deriving elemental abundances from ion abundances. Andreã et al. (1991) used an ionization correction method to obtain their abundances and ...

  17. The Stellar Oxygen Abundance Gradient in M33

    Science.gov (United States)

    Monteverde, M. I.; Herrero, A.; Lennon, D. J.; Kudritzki, R.-P.

    1997-01-01

    We report here first results concerning stellar oxygen abundances in M33. Non-LTE model atmosphere and non-LTE line formation calculations were used to determine the oxygen abundance of B-type supergiants. By choosing stars located at different projected radial distances to the center of M33, we are able to determine the oxygen abundance gradient, for which we obtain a value of -0.16 +/- 0.06 dex kpc-1. This is the first time that the oxygen stellar abundance gradient has been determined in a spiral galaxy other than the Milky Way.

  18. 2 D gel based analysis of biological variability of the human plasma proteome

    DEFF Research Database (Denmark)

    Rentsch, Maria Louise; Jessen, Flemming

    Human blood plasma is a valuable specimen for the biomarker discovery process, since it is easily accessible and contains proteins that are synthesised, secreted or lost from cells and tissue. In this way, changes in plasma proteome reflect the current state of the organism. The analysis of plasma...... by one-week interval. Blood samples were drawn before the meal intake and five times during 24 hours for proteome analysis. Plasma was fractionated by use of IgY-12 spin column depleting the 12 highly abundant proteins and further processed for two-dimensional gel electrophoresis. The plasma proteome...... proteome is yet challenging due to the huge dynamic range of protein abundance. When evaluating a potential biomarker, stable basal level of the protein is needed before it can be considered a functional biomarker. However, basal level differences of plasma proteins are naturally occurring between...

  19. Colloidal Plasmas : Basic physics of colloidal plasmas

    Indian Academy of Sciences (India)

    C B Dwivedi

    2000-11-01

    Colloidal plasma is a distinct class of the impure plasmas with multispecies ionic composition. The distinction lies in the phase distribution of the impurity-ion species. The ability to tailor the electrostatic interactions between these colloidal particles provides a fertile ground for scientists to investigate the fundamental aspects of the Coulomb phase transition behavior. The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various acoustic modes, which are likely to exist in colloidal plasmas as well as in normal multi-ion species plasmas. Introductory ideas about the proposed physical models for the Coulomb phase transition in colloidal plasma will also be discussed.

  20. Experimental evaluation of fractional abundance data for W23+–W28+

    Science.gov (United States)

    Fujii, Keisuke; Kato, Daiji; Nakamura, Nobuyuki; Goto, Motoshi; Morita, Shigeru; Hasuo, Masahiro

    2017-03-01

    Based on the electron temperature (T e) dependence of 20 forbidden tungsten line intensities observed in several Large Helical Device discharges, we experimentally evaluated fractional abundance profiles for highly charged tungsten ions (W) in the charge states 23–28. Although the absolute values of the fractional abundance are still inaccessible in our method, relative profiles against T e values were evaluated. The T e values at the profile peak for q = 23, 24, 25, 26, 27 and 28 states tungsten abundance were evaluated as 0.53, 0.58, 0.65, 0.78, 0.93, and 1.14 keV, respectively. These results were ≈20% smaller than those reported by Pütterich et al (2008 Plasma Phys. Control. Fusion 50 085016), which are the theoretical calculations adjusted to match the quasi-continuum emission by q = 24–35 tungsten ions measured in the extreme ultraviolet region, and ≈60% larger than the pure theoretical calculation by Sasaki et al (2013 J. Phys. B: At. Mol. Opt. Phys. 46 175701).

  1. Nonlinear plasma wave in magnetized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bulanov, Sergei V. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 (Russian Federation); Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Hosokai, Tomonao; Zhidkov, Alexei G. [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Kodama, Ryosuke [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  2. Herbivore regulation of plant abundance in aquatic ecosystems.

    Science.gov (United States)

    Wood, Kevin A; O'Hare, Matthew T; McDonald, Claire; Searle, Kate R; Daunt, Francis; Stillman, Richard A

    2017-05-01

    Herbivory is a fundamental process that controls primary producer abundance and regulates energy and nutrient flows to higher trophic levels. Despite the recent proliferation of small-scale studies on herbivore effects on aquatic plants, there remains limited understanding of the factors that control consumer regulation of vascular plants in aquatic ecosystems. Our current knowledge of the regulation of primary producers has hindered efforts to understand the structure and functioning of aquatic ecosystems, and to manage such ecosystems effectively. We conducted a global meta-analysis of the outcomes of plant-herbivore interactions using a data set comprised of 326 values from 163 studies, in order to test two mechanistic hypotheses: first, that greater negative changes in plant abundance would be associated with higher herbivore biomass densities; second, that the magnitude of changes in plant abundance would vary with herbivore taxonomic identity. We found evidence that plant abundance declined with increased herbivore density, with plants eliminated at high densities. Significant between-taxa differences in impact were detected, with insects associated with smaller reductions in plant abundance than all other taxa. Similarly, birds caused smaller reductions in plant abundance than echinoderms, fish, or molluscs. Furthermore, larger reductions in plant abundance were detected for fish relative to crustaceans. We found a positive relationship between herbivore species richness and change in plant abundance, with the strongest reductions in plant abundance reported for low herbivore species richness, suggesting that greater herbivore diversity may protect against large reductions in plant abundance. Finally, we found that herbivore-plant nativeness was a key factor affecting the magnitude of herbivore impacts on plant abundance across a wide range of species assemblages. Assemblages comprised of invasive herbivores and native plant assemblages were associated with

  3. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  4. Estrogenic compounds decrease growth hormone receptor abundance and alter osmoregulation in Atlantic salmon

    Science.gov (United States)

    Lerner, Darren T.; Sheridan, Mark A.; McCormick, Stephen D.

    2012-01-01

    Exposure of Atlantic salmon smolts to estrogenic compounds is shown to compromise several aspects of smolt development. We sought to determine the underlying endocrine mechanisms of estrogen impacts on the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. Smolts in freshwater (FW) were either injected 3 times over 10 days with 2 μg g−1 17β-estradiol (E2) or 150 μg g−1 4-nonylphenol (NP). Seawater (SW)-acclimated fish received intraperitoneal implants of 30 μg g−1 E2 over two weeks. Treatment with these estrogenic compounds increased hepatosomatic index and total plasma calcium. E2 and NP reduced maximum growth hormone binding by 30–60% in hepatic and branchial membranes in FW and SW, but did not alter the dissociation constant. E2 and NP treatment decreased plasma levels of IGF-I levels in both FW and SW. In FW E2 and NP decreased plasma GH whereas in SW plasma GH increased after E2 treatment. Compared to controls, plasma chloride concentrations of E2-treated fish were decreased 5.5 mM in FW and increased 10.5 mM in SW. There was no effect of NP or E2 on gill sodium–potassium adenosine triphosphatase (Na+/K+-ATPase) activity in FW smolts, whereas E2 treatment in SW reduced gill Na+/K+-ATPase activity and altered the number and size of ionocytes. Our data indicate that E2 downregulates the GH/IGF-I-axis and SW tolerance which may be part of its normal function for reproduction and movement into FW. We conclude that the mechanism of endocrine disruption of smolt development by NP is in part through alteration of the GH/IGF-I axis via reduced GH receptor abundance.

  5. Active control of magneto-hydrodynamic instabilities in hot plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Igochine, Valentin (ed.) [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2015-04-01

    Written and edited by leading plasma physics researchers. Provides a toolkit for scientists and engineers aiming to optimize plasma performance. Comprehensive treatment of different plasma instabilities. During the past century, world-wide energy consumption has risen dramatically, which leads to a quest for new energy sources. Fusion of hydrogen atoms in hot plasmas is an attractive approach to solve the energy problem, with abundant fuel, inherent safety and no long-lived radioactivity. However, one of the limits on plasma performance is due to the various classes of magneto-hydrodynamic instabilities that may occur. The physics and control of these instabilities in modern magnetic confinement fusion devices is the subject of this book. Written by foremost experts, the contributions will provide valuable reference and up-to-date research reviews for ''old hands'' and newcomers alike.

  6. Reviews of plasma physics

    CERN Document Server

    2008-01-01

    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  7. Reviews of plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Shafranov, Vitalii Dmitrievich (ed.); Bakunin, Oleg G. (comps.) [Rossijskij Nauchnyj Tsentr ' ' Kurchatovskij Inst.' ' , Moscow (Russian Federation). Nuclear Fusion Inst.; Rozhansky, V. [St. Petersburg State Polytechnical Univ. (Russian Federation)

    2008-07-01

    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  8. Use of Differential Scanning Calorimetry and Immunoaffinity Chromatography to Identify Disease Induced Changes in Human Blood Plasma Proteome.

    Science.gov (United States)

    Brudar, Sandi; Černigoj, Urh; Podgornik, Helena; Kržan, Mojca; Prislan, Iztok

    2017-09-01

    Differential scanning calorimetry provides unique signatures of blood plasma samples. Plasma samples from diseased individuals yield specific thermograms, which differ from each other and from plasma samples of healthy individuals. Thermograms from individuals suffering from chronic lymphocytic leukemia, multiple myeloma and acute myeloid leukemia were measured with DSC. To obtain additional information about thermal behaviour of plasma proteins immunoaffinity chromatography was introduced. An immunoextraction of HSA using a chromatographic column with immobilized anti-HSA was carried out in order to enrich less abundant plasma proteins, which could provide a further insight into disease development. Efficiency of HSA depletion and protein composition of fractionated plasma was validated by SDS-PAGE.

  9. A protocol for sampling vascular epiphyte richness and abundance

    NARCIS (Netherlands)

    Wolf, J.H.D.; Gradstein, S.R.; Nadkarni, N.M.

    2009-01-01

    The sampling of epiphytes is fraught with methodological difficulties. We present a protocol to sample and analyse vascular epiphyte richness and abundance in forests of different structure (SVERA). Epiphyte abundance is estimated as biomass by recording the number of plant components in a range of

  10. Abundance – A new window on how disruptive innovation occurs

    NARCIS (Netherlands)

    Mahto, Raj V.; Belousova, Olga; Ahluwalia, Saurabh

    2017-01-01

    The economic philosophy of abundance has provided a new portal to view disruptive innovation. After decades of the world's middle class shrinking and the poor becoming poorer the abundance concept has created an interest in the “Rising Billion” transforming the poor into a more viable economic force

  11. Variation in rank abundance replicate samples and impact of clustering

    NARCIS (Netherlands)

    Neuteboom, J.H.; Struik, P.C.

    2005-01-01

    Calculating a single-sample rank abundance curve by using the negative-binomial distribution provides a way to investigate the variability within rank abundance replicate samples and yields a measure of the degree of heterogeneity of the sampled community. The calculation of the single-sample rank a

  12. The end of abundance. Economic solutions to water scarcity

    NARCIS (Netherlands)

    Zetland, D.J.

    2011-01-01

    In a past of abundance, we had clean water to meet our demands for showers, pools, farms and rivers. Our laws and customs did not need to regulate or ration demand. Over time, our demand has grown, and scarcity has replaced abundance. We don't have as much clean water as we want. We can respond to t

  13. Detecting novel low-abundant transcripts in Drosophila

    DEFF Research Database (Denmark)

    Lee, Sanggyu; Bao, Jingyue; Zhou, Guolin;

    2005-01-01

    Increasing evidence suggests that low-abundant transcripts may play fundamental roles in biological processes. In an attempt to estimate the prevalence of low-abundant transcripts in eukaryotic genomes, we performed a transcriptome analysis in Drosophila using the SAGE technique. We collected 244...

  14. The implicit assumption of symmetry and the species abundance distribution

    NARCIS (Netherlands)

    Alonso, David; Ostling, Annette; Etienne, Rampal S.

    Species abundance distributions (SADs) have played a historical role in the development of community ecology. They summarize information about the number and the relative abundance of the species encountered in a sample from a given community. For years ecologists have developed theory to

  15. Progress of International Low-Temperature Plasma Research Overview of the 15th International Symposium on Plasma Chemistry

    Institute of Scientific and Technical Information of China (English)

    吴承康

    2001-01-01

    International Symposium on Plasma Chemistry (ISPC) is the most influencial international symposium on science and technology research of low-temperature plasma, especially in the fields related to materials processing. People can be rightly informed of the current devel oping trend of this field from the contents of these symposia. This paper vill introduce briefly a general overview of the 15th ISPC. As viewed from the number of papers and their contents, there is still abundant research on thermal plasma, and the needs for micro-electronic technology and high performance films have driven forward continuous and intensive development of the research on low-pressure, non-equilibrium plasmas, while the research on normal pressure, non-equilibrium plasma has become a new highlight in this field.``

  16. Abundance Survey of M and K Dwarf Stars

    Energy Technology Data Exchange (ETDEWEB)

    Woolf, Vincent M. [Astronomy Department, University of Washington, Seattle, WA 98133 (United States); Wallerstein, George [Astronomy Department, University of Washington, Seattle, WA 98133 (United States)

    2005-07-25

    We report the measurement of chemical abundances in 35 low-mass main sequence (M and K dwarf) stars. We have measured the abundance of 12 elements in Kapteyn's Star, a nearby halo M subdwarf. The abundances indicate an iron abundance of [Fe/H] = -0.98, which is about 0.5 dex smaller than that measured in the only previous published measurement using atomic absorption lines. We have measured Fe and Ti abundances in 35 M and K dwarfs with -2.39 [Fe/H] +0.21 using atomic absorption lines, mostly in the 8000A <{lambda} < 8850A range. These will be used to calibrate photometric and low-resolution spectrum metallicity indices for low mass dwarfs, which will make metallicity estimates for these stars more certain. We also describe some difficulties encountered which are not normally necessary to consider when studying warmer stars.

  17. The Detailed Chemical Abundance Patterns of M31 Globular Clusters

    CERN Document Server

    Colucci, J E; Cohen, J

    2012-01-01

    We present detailed chemical abundances for $>$20 elements in $\\sim$30 globular clusters in M31. These results have been obtained using high resolution ($\\lambda/\\Delta\\lambda\\sim$24,000) spectra of their integrated light and analyzed using our original method. The globular clusters have galactocentric radii between 2.5 kpc and 117 kpc, and therefore provide abundance patterns for different phases of galaxy formation recorded in the inner and outer halo of M31. We find that the clusters in our survey have a range in metallicity of $-2.2$20 kpc have a small range in abundance of [Fe/H]$=-1.6 \\pm 0.10$. We also measure abundances of alpha, r- and s-process elements. These results constitute the first abundance pattern constraints for old populations in M31 that are comparable to those known for the Milky Way halo.

  18. Ionized Gaseous Nebulae Abundance Determination from the Direct Method

    Science.gov (United States)

    Pérez-Montero, Enrique

    2017-04-01

    This tutorial explains the procedure used to analyze an optical emission-line spectrum produced by a nebula ionized by massive star formation. Particularly, the methodology used to derive physical properties, such as electron density and temperature, and the ionic abundances of the most representative elements whose emission lines are present in the optical spectrum is described. The main focus is on the direct method, which is based on the measurement of the electron temperature to derive the abundances, given that the ionization and thermal equilibrium of the ionized gas is dominated by the metallicity. The ionization correction factors used to obtain total abundances from the abundances of some of their ions are also given. Finally, some strong-line methods to derive abundances are described. Such methods are used when no estimation of the temperature can be derived, but which can be consistent with the direct method if they are empirically calibrated.

  19. Abundance sensitive points of line profiles in the stellar spectra

    CERN Document Server

    Sheminova, V A

    2014-01-01

    Many abundance studies are based on spectrum synthesis and $\\chi$-squared differences between the synthesized and an observed spectrum. Much of the spectra so compared depend only weakly on the elemental abundances. Logarithmic plots of line depths rather than relative flux make this more apparent. We present simulations that illustrate a simple method for finding regions of the spectrum most sensitive to abundance, and also some caveats for using such information. As expected, we find that weak features are the most sensitive. Equivalent widths of weak lines are ideal features, because of their sensitivity to abundances, and insensitivity to factors that broaden the line profiles. The wings of strong lines can also be useful, but it is essential that the broadening mechanisms be accurately known. The very weakest features, though sensitive to abundance, should be avoided or used with great caution because of uncertainty of continuum placement as well as numerical uncertainties associated with the subtraction...

  20. Electron thermal transport in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Konings, J.A.

    1994-11-30

    The process of fusion of small nuclei thereby releasing energy, as it occurs continuously in the sun, is essential for the existence of mankind. The same process applied in a controlled way on earth would provide a clean and an abundant energy source, and be the long term solution of the energy problem. Nuclear fusion requires an extremely hot (10{sup 8} K) ionized gas, a plasma, that can only be maintained if it is kept insulated from any material wall. In the so called `tokamak` this is achieved by using magnetic fields. The termal insulation, which is essential if one wants to keep the plasma at the high `fusion` temperature, can be predicted using basic plasma therory. A comparison with experiments in tokamaks, however, showed that the electron enery losses are ten to hundred times larger than this theory predicts. This `anomalous transport` of thermal energy implies that, to reach the condition for nuclear fusion, a fusion reactor must have very large dimensions. This may put the economic feasibility of fusion power in jeopardy. Therefore, in a worldwide collaboration, physicists study tokamak plasmas in an attempt to understand and control the energy losses. From a scientific point of view, the mechanisms driving anomalous transport are one of the challenges in fudamental plasma physics. In Nieuwegein, a tokamak experiment (the Rijnhuizen Tokamak Project, RTP) is dedicated to the study of anomalous transport, in an international collaboration with other laboratories. (orig./WL).

  1. Star formation and the interstellar medium in low surface brightness galaxies; 1, Oxygen abundances and abundance gradients in low surface brightness disk galaxies

    NARCIS (Netherlands)

    Blok, W. J. G. de; Hulst, J. M. van der

    1998-01-01

    Submitted to: Astron. Astrophys. Abstract: We present measurements of the oxygen abundances in 64 HII regions in 12 LSB galaxies. We find that oxygen abundances are low. No regions with solar abundance have been found, and most have oxygen abundances $sim 0.5$ to 0.1 solar. The oxygen abundance appe

  2. Experimental and theoretical oscillator strengths of Mg i for accurate abundance analysis

    Science.gov (United States)

    Pehlivan Rhodin, A.; Hartman, H.; Nilsson, H.; Jönsson, P.

    2017-02-01

    Context. With the aid of stellar abundance analysis, it is possible to study the galactic formation and evolution. Magnesium is an important element to trace the α-element evolution in our Galaxy. For chemical abundance analysis, such as magnesium abundance, accurate and complete atomic data are essential. Inaccurate atomic data lead to uncertain abundances and prevent discrimination between different evolution models. Aims: We study the spectrum of neutral magnesium from laboratory measurements and theoretical calculations. Our aim is to improve the oscillator strengths (f-values) of Mg i lines and to create a complete set of accurate atomic data, particularly for the near-IR region. Methods: We derived oscillator strengths by combining the experimental branching fractions with radiative lifetimes reported in the literature and computed in this work. A hollow cathode discharge lamp was used to produce free atoms in the plasma and a Fourier transform spectrometer recorded the intensity-calibrated high-resolution spectra. In addition, we performed theoretical calculations using the multiconfiguration Hartree-Fock program ATSP2K. Results: This project provides a set of experimental and theoretical oscillator strengths. We derived 34 experimental oscillator strengths. Except from the Mg i optical triplet lines (3p 3P°0,1,2-4s 3S1), these oscillator strengths are measured for the first time. The theoretical oscillator strengths are in very good agreement with the experimental data and complement the missing transitions of the experimental data up to n = 7 from even and odd parity terms. We present an evaluated set of oscillator strengths, gf, with uncertainties as small as 5%. The new values of the Mg i optical triplet line (3p 3P°0,1,2-4s 3S1) oscillator strength values are 0.08 dex larger than the previous measurements.

  3. ANOMALOUS RELATIVE AR/CA CORONAL ABUNDANCES OBSERVED BY THE HINODE/EUV IMAGING SPECTROMETER NEAR SUNSPOTS

    Energy Technology Data Exchange (ETDEWEB)

    Doschek, G. A.; Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Feldman, U. [Artep, Inc., 2922 Excelsior Springs Court, Ellicott City, MD 21042 (United States)

    2015-07-20

    In determining the element abundance of argon (a high first ionization potential; FIP element) relative to calcium (a low FIP element) in flares, unexpectedly high intensities of two Ar xiv lines (194.40, 187.96 Å) relative to a Ca xiv line (193.87 Å) intensity were found in small (a few arcseconds) regions near sunspots in flare spectra recorded by the Extreme-ultraviolet Imaging Spectrometer on the Hinode spacecraft. In the most extreme case the Ar xiv line intensity relative to the Ca xiv intensity was 7 times the value expected from the photospheric abundance ratio, which is about 30 times the abundance of argon relative to calcium in active regions, i.e., the measured Ar/Ca abundance ratio is about 10 instead of 0.37 as in active regions. The Ar xiv and Ca xiv lines are formed near 3.4 MK and have very similar contribution functions. This is the first observation of the inverse FIP effect in the Sun. Other regions show increases of 2–3 over photospheric abundances, or just photospheric abundances. This phenomenon appears to occur rarely and only over small areas of flares away from the regions containing multi-million degree plasma, but more work is needed to quantify the occurrences and their locations. In the bright hot regions of flares the Ar/Ca abundance ratio is coronal, i.e., the same as in active regions. In this Letter we show three examples of the inverse FIP effect.

  4. Hot plasma dielectric tensor

    NARCIS (Netherlands)

    Westerhof, E.

    1996-01-01

    The hot plasma dielectric tensor is discussed in its various approximations. Collisionless cyclotron resonant damping and ion/electron Bernstein waves are discussed to exemplify the significance of a kinetic description of plasma waves.

  5. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  6. IgY14 and SuperMix immunoaffinity separations coupled with liquid chromatography-mass spectrometry for human plasma proteomic biomarker discovery

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Tujin; Zhou, Jianying; Gritsenko, Marina A.; Hossain, Mahmud; Camp, David G.; Smith, Richard D.; Qian, Weijun

    2012-02-01

    Interest in the application of advanced proteomics technologies to human blood plasma- or serum-based clinical samples for the purpose of discovering disease biomarkers continues to grow; however, the enormous dynamic range of protein concentrations in these types of samples (often >10 orders of magnitude) represents a significant analytical challenge, particularly for detecting low-abundance candidate biomarkers. In response, immunoaffinity separation methods for depleting multiple high- and moderate-abundance proteins have become key tools for enriching low-abundance proteins and enhancing detection of these proteins in plasma proteomics. Herein, we describe IgY14 and tandem IgY14-Supermix separation methods for removing 14 high-abundance and up to 60 moderate-abundance proteins, respectively, from human blood plasma and highlight their utility when combined with liquid chromatography-tandem mass spectrometry for interrogating the human plasma proteome.

  7. IgY14 and SuperMix immunoaffinity separations coupled with liquid chromatography-mass spectrometry for human plasma proteomics biomarker discovery.

    Science.gov (United States)

    Shi, Tujin; Zhou, Jian-Ying; Gritsenko, Marina A; Hossain, Mahmud; Camp, David G; Smith, Richard D; Qian, Wei-Jun

    2012-02-01

    Interest in the application of advanced proteomics technologies to human blood plasma- or serum-based clinical samples for the purpose of discovering disease biomarkers continues to grow; however, the enormous dynamic range of protein concentrations in these types of samples (often >10 orders of magnitude) represents a significant analytical challenge, particularly for detecting low-abundance candidate biomarkers. In response, immunoaffinity separation methods for depleting multiple high- and moderate-abundance proteins have become key tools for enriching low-abundance proteins and enhancing detection of these proteins in plasma proteomics. Herein, we describe IgY14 and tandem IgY14-Supermix separation methods for removing 14 high-abundance and up to 60 moderate-abundance proteins, respectively, from human blood plasma and highlight their utility when combined with liquid chromatography-tandem mass spectrometry for interrogating the human plasma proteome.

  8. Microwave Argon Plasma Torch

    Science.gov (United States)

    2013-07-01

    an electron-ion pair in the discharge. Fig. 2. EEDF is non - Maxwellian and changes along the plasma column The electron–neutral collision...plasma radius. Even at atmospheric pressure the EEDF is non - Maxwellian and it is changing along the plasma column. ...18 31st ICPIG, July 14-19, 2013, Granada, Spain EEDF usually strongly differs from Maxwellian and chages along the plasma column (this is

  9. Introduction to Plasma Physics

    Science.gov (United States)

    Gurnett, Donald A.; Bhattacharjee, Amitava

    2017-03-01

    Preface; 1. Introduction; 2. Characteristic parameters of a plasma; 3. Single particle motions; 4. Waves in a cold plasma; 5. Kinetic theory and the moment equations; 6. Magnetohydrodynamics; 7. MHD equilibria and stability; 8. Discontinuities and shock waves; 9. Electrostatic waves in a hot unmagnetized plasma; 10. Waves in a hot magnetized plasma; 11. Nonlinear effects; 12. Collisional processes; Appendix A. Symbols; Appendix B. Useful trigonometric identities; Appendix C. Vector differential operators; Appendix D. Vector calculus identities; Index.

  10. Plasma physics an introduction

    CERN Document Server

    Fitzpatrick, Richard

    2014-01-01

    Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics.

  11. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  12. Plasma in dentistry

    OpenAIRE

    Cha, Seunghee; Park, Young-Seok

    2014-01-01

    This review describes the contemporary aspects of plasma application in dentistry. Previous studies on plasma applications were classified into two categories, surface treatment and direct applications, and were reviewed, respectively according to the approach. The current review discussed modification of dental implant surface, enhancing of adhesive qualities, enhancing of polymerization, surface coating and plasma cleaning under the topics of surface treatment. Microbicidal activities, deco...

  13. The Plasma Universe

    Science.gov (United States)

    Suplee, Curt

    2009-09-01

    Preface; 1. The fourth state of matter; 2. The music and dance of plasmas; 3. The Sun-Earth connection; 4. Bringing the Sun to Earth: the story of controlled thermonuclear fusion; 5. The cosmic plasma theater: galaxies, stars, and accretion disks; 6. Putting plasmas to work; Index.

  14. Seasonal Abundance of Aphids and Aphidophagous Insects in Pecan

    Directory of Open Access Journals (Sweden)

    Ghulam Abbas

    2012-12-01

    Full Text Available Seasonal occurrence of aphids and aphidophagous insects was monitored for six years (2006–2011 from full leaf expansion in May to leaf fall in October in “Desirable” variety pecan trees that were not treated with insecticides. Aphid outbreaks occurred two times per season, once in the spring and again in the late summer. Yellow pecan and blackmargined aphids exceeded the recommended treatment thresholds one time and black pecan aphids exceeded the recommended treatment levels three times over the six seasons. Increases in aphidophagous insect abundance coincided with aphid outbreaks in five of the six seasons. Among aphidophagous insects Harmonia axyridis and Olla v-nigrum were frequently collected in both the tree canopy and at the ground level, whereas, Coccinella septempunctata, Hippodamia convergens were rarely found in the tree canopy and commonly found at the ground level. Green lacewing abundance was higher in the ground level than in the tree canopy. Brown lacewings were more abundant in the tree canopy than at the ground level. Dolichopodid and syrphid fly abundance, at the ground level increased during peak aphid abundance in the tree canopy. Application of an aqueous solution of fermenting molasses to the pecan foliage during an aphid outbreak significantly increased the abundance of ladybeetles and lacewings and significantly reduced the abundance of yellow pecan, blackmargined and black pecan aphids.

  15. Stellar abundances in the solar neighborhood: The Hypatia Catalog

    Energy Technology Data Exchange (ETDEWEB)

    Hinkel, Natalie R.; Timmes, F.X.; Young, Patrick A.; Pagano, Michael D. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Turnbull, Margaret C. [Global Science Institute, P.O. Box 252, Antigo, WI 54409 (United States)

    2014-09-01

    We compile spectroscopic abundance data from 84 literature sources for 50 elements across 3058 stars in the solar neighborhood, within 150 pc of the Sun, to produce the Hypatia Catalog. We evaluate the variability of the spread in abundance measurements reported for the same star by different surveys. We also explore the likely association of the star within the Galactic disk, the corresponding observation and abundance determination methods for all catalogs in Hypatia, the influence of specific catalogs on the overall abundance trends, and the effect of normalizing all abundances to the same solar scale. The resulting stellar abundance determinations in the Hypatia Catalog are analyzed only for thin-disk stars with observations that are consistent between literature sources. As a result of our large data set, we find that the stars in the solar neighborhood may reveal an asymmetric abundance distribution, such that a [Fe/H]-rich group near the midplane is deficient in Mg, Si, S, Ca, Sc II, Cr II, and Ni as compared to stars farther from the plane. The Hypatia Catalog has a wide number of applications, including exoplanet hosts, thick- and thin-disk stars, and stars with different kinematic properties.

  16. Geographical range and local abundance of tree species in China.

    Directory of Open Access Journals (Sweden)

    Haibao Ren

    Full Text Available Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1 whether locally abundant species tend to be geographically widespread; 2 whether species are more abundant towards their range-centers; and 3 how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20-25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km(2, and >90% of 651 species had ranges >10(5 km(2. There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species' abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges.

  17. Model reduction for stochastic chemical systems with abundant species

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Stephen; Cianci, Claudia; Grima, Ramon [School of Biological Sciences, University of Edinburgh, Mayfield Road, Edinburgh EH93JR, Scotland (United Kingdom)

    2015-12-07

    Biochemical processes typically involve many chemical species, some in abundance and some in low molecule numbers. We first identify the rate constant limits under which the concentrations of a given set of species will tend to infinity (the abundant species) while the concentrations of all other species remains constant (the non-abundant species). Subsequently, we prove that, in this limit, the fluctuations in the molecule numbers of non-abundant species are accurately described by a hybrid stochastic description consisting of a chemical master equation coupled to deterministic rate equations. This is a reduced description when compared to the conventional chemical master equation which describes the fluctuations in both abundant and non-abundant species. We show that the reduced master equation can be solved exactly for a number of biochemical networks involving gene expression and enzyme catalysis, whose conventional chemical master equation description is analytically impenetrable. We use the linear noise approximation to obtain approximate expressions for the difference between the variance of fluctuations in the non-abundant species as predicted by the hybrid approach and by the conventional chemical master equation. Furthermore, we show that surprisingly, irrespective of any separation in the mean molecule numbers of various species, the conventional and hybrid master equations exactly agree for a class of chemical systems.

  18. Beryllium Abundances in Stars of One-Solar-Mass

    CERN Document Server

    Boesgaard, Ann Merchant

    2008-01-01

    We have determined Be abundances in 50 F and G dwarfs in the mass range of 0.9 $\\leq$ M$_\\odot$ $\\leq$ 1.1 as determined by Lambert & Reddy. The effective temperatures are 5600 to 6400 K and metallicities from $-$0.65 to +0.11. The spectra were taken primarily with Keck I + HIRES. The Be abundances were found via spectral synthesis of Be II lines near 3130 \\AA. The Be abundances were investigated as a function of age, temperature, metallicity and Li abundance in this narrow mass range. Even though our stars are similar in mass, they show a range in Be abundances of a factor of $>$40. We find that [Be/Fe] has no dependence on temperature, but does show a spread of a factor of 6 at a given temperature. The reality of the spread is shown by two identical stars which differ from each other by a factor of two only in their abundances of Li and Be. Our thin-disk-star sample fits the trend between Be abundance and [Fe/H] found for halo and thick disk stars, extending it to about 4 orders of magnitude in the two ...

  19. Dam removal increases American eel abundance in distant headwater streams

    Science.gov (United States)

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.

    2012-01-01

    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  20. (Un)true deuterium abundance in the Galactic disk

    Science.gov (United States)

    Prodanović, Tijana; Steigman, Gary; Fields, Brian D.

    2010-04-01

    Deuterium has a special place in cosmology, nuclear astrophysics, and galactic chemical evolution, because of its unique property that it is only created in the big bang nucleosynthesis while all other processes result in its net destruction. For this reason, among other things, deuterium abundance measurements in the interstellar medium (ISM) allow us to determine the fraction of interstellar gas that has been cycled through stars, and set constraints and learn about different Galactic chemical evolution (GCE) models. However, recent indications that deuterium might be preferentially depleted onto dust grains complicate our understanding about the meaning of measured ISM deuterium abundances. For this reason, recent estimates by Linsky et al. (2006) have yielded a lower bound to the “true”, undepleted, ISM deuterium abundance that is very close to the primordial abundance, indicating a small deuterium astration factor contrary to the demands of many GCE models. To avoid any prejudice about deuterium dust depletion along different lines of sight that are used to determine the “true” D abundance, we propose a model-independent, statistical Bayesian method to address this issue and determine in a model-independent manner the undepleted ISM D abundance. We find the best estimate for the gas-phase ISM deuterium abundance to be (D/H)ISM ≥ (2.0 ± 0.1) × 10-5. Presented are the results of Prodanović et al. (2009).

  1. Understanding and reducing statistical uncertainties in nebular abundance determinations

    Science.gov (United States)

    Wesson, R.; Stock, D. J.; Scicluna, P.

    2012-06-01

    Whenever observations are compared to theories, an estimate of the uncertainties associated with the observations is vital if the comparison is to be meaningful. However, many or even most determinations of temperatures, densities and abundances in photoionized nebulae do not quote the associated uncertainty. Those that do typically propagate the uncertainties using analytical techniques which rely on assumptions that generally do not hold. Motivated by this issue, we have developed Nebular Empirical Analysis Tool (NEAT), a new code for calculating chemical abundances in photoionized nebulae. The code carries out a standard analysis of lists of emission lines using long-established techniques to estimate the amount of interstellar extinction, calculate representative temperatures and densities, compute ionic abundances from both collisionally excited lines and recombination lines, and finally to estimate total elemental abundances using an ionization correction scheme. NEATuses a Monte Carlo technique to robustly propagate uncertainties from line flux measurements through to the derived abundances. We show that, for typical observational data, this approach is superior to analytic estimates of uncertainties. NEAT also accounts for the effect of upward biasing on measurements of lines with low signal-to-noise ratio, allowing us to accurately quantify the effect of this bias on abundance determinations. We find not only that the effect can result in significant overestimates of heavy element abundances derived from weak lines, but also that taking it into account reduces the uncertainty of these abundance determinations. Finally, we investigate the effect of possible uncertainties in R, the ratio of selective-to-total extinction, on abundance determinations. We find that the uncertainty due to this parameter is negligible compared to the statistical uncertainties due to typical line flux measurement uncertainties.

  2. Pex35 is a regulator of peroxisome abundance

    DEFF Research Database (Denmark)

    Yofe, Ido; Soliman, Kareem; Chuartzman, Silvia G

    2017-01-01

    Peroxisomes are cellular organelles with vital functions in lipid, amino acid, and redox metabolism. The cellular formation and dynamics of peroxisomes are governed by PEX genes, however, the regulation of peroxisome abundance is yet poorly understood. Here we use a high-content microscopy screen...... to identify novel regulators of peroxisome size and abundance. Our screen led to the identification of a previously uncharacterized gene, which we term PEX35, which affects peroxisome abundance. PEX35 encodes a peroxisomal membrane protein, a remote homolog to several curvature generating human proteins. We...

  3. Trace-element abundances in several new ureilites

    Science.gov (United States)

    Boynton, William V.; Hill, Dolores H.

    1993-01-01

    Four new ureilites are analyzed for trace-element abundances. Frontier Mountain (FRO) 90054 is an augite-rich ureilite and has high rare earth element (REE) abundances with a pattern expected of augite. FRO 90036 and Acfer 277 have REE patterns similar to the V-shape pattern of other ureilites. Nuevo Mercurio (b) has very high REE abundances, but they look like they are due to terrestrial alteration. The siderophile-element pattern of these ureilites are similar to those of known ureilites.

  4. Oxygen and nitrogen abundances in Virgo and field spirals

    OpenAIRE

    Pilyugin, L. S.; Molla, Mercedes; Ferrini, Federico; Vilchez, Jose M.

    2001-01-01

    The oxygen and nitrogen abundances in the HII regions of the nine Virgo spirals of the sample from Skillman et al (1996) and in nine field spiral galaxies are re-determined with the recently suggested P - method. We confirm that there is an abundance segregation in the sample of Virgo spirals in the sense that the HI deficient Virgo spirals near the core of the cluster have higher oxygen abundances in comparison to the spirals at the periphery of the Virgo cluster. At the same time both the V...

  5. The determination of electron abundances in interstellar clouds

    Science.gov (United States)

    Wootten, A.; Snell, R.; Glassgold, A. E.

    1979-01-01

    An independent method is proposed for the determination of electron abundances in dense clouds based upon the abundance ratio of HCO(+) and CO. The method is derived from a simple application of gas phase ion molecule interstellar chemistry. It is noted that unlike the fractionation of deuterated molecules, it applies to warm as well as to cool clouds. The method is illustrated with the results of the recent abundance survey of Wooten et al. (1978). Finally, it is shown that in cases where deuterium enhancement is measured, an upper limit can be obtained for the cosmic ray ionization rate.

  6. Dust formation in a galaxy with primitive abundances.

    Science.gov (United States)

    Sloan, G C; Matsuura, M; Zijlstra, A A; Lagadec, E; Groenewegen, M A T; Wood, P R; Szyszka, C; Bernard-Salas, J; van Loon, J Th

    2009-01-16

    Interstellar dust plays a crucial role in the evolution of galaxies. It governs the chemistry and physics of the interstellar medium. In the local universe, dust forms primarily in the ejecta from stars, but its composition and origin in galaxies at very early times remain controversial. We report observational evidence of dust forming around a carbon star in a nearby galaxy with a low abundance of heavy elements, 25 times lower than the solar abundance. The production of dust by a carbon star in a galaxy with such primitive abundances raises the possibility that carbon stars contributed carbonaceous dust in the early universe.

  7. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  8. Plasma Therapy: An Overview

    Directory of Open Access Journals (Sweden)

    Rajkumar Diwan

    2011-01-01

    Full Text Available Definition: Plasma, the fourth state of matter, is a collection of charged particles (electrons, ions, neutral atoms. Recent demonstration of plasma technology in treatment of living cells, tissue and organs are creating a new field at the intersection of plasma science and technology with biology and medicine known as plasma medicine. Plasma medicine is one of the newest fields of modem applied plasma chemistry. It appeared several years ago and comprises studies concerning the direct action of low-temperature, one atmosphere air plasma (cold plasma/nonthermal plasmalnonequilibrium on body tissues for various noninvasive therapeutic treatments or diagnostics purpose. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumors and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and environmental pathogens, heat-sensitive materials, hard and soft surfaces, and may assist health care facilities in the management of various health concerns. The role that low temperature atmospheric pressure plasma (LTAPP could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, more economical alternative.

  9. Arc Plasma Torch Modeling

    CERN Document Server

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  10. Laminar Plasma Dynamos

    CERN Document Server

    Wang, Z; Barnes, C W; Barnes, D C; Wang, Zhehui; Pariev, Vladimir I.; Barnes, Cris W.; Barnes, Daniel C.

    2002-01-01

    A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As opposed to intrinsically-turbulent liquid-sodium dynamos, the proposed plasma dynamos correspond to laminar flow topology. Modest plasma parameters, 1-20 eV temperatures, 10^{19}-10^{20} m^{-3} densities in 0.3-1.0 m scale-lengths driven by velocities on the order of the Alfven Critical Ionization Velocity (CIV), self-consistently satisfy the conditions needed for the magnetic field amplication. Growth rates for the plasma dynamos are obtained numerically with different geometry and magnetic Reynolds numbers. Magnetic-field-free coaxial plasma guns can be used to sustain the plasma flow and the dynamo.

  11. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike

    2008-01-01

    In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode......, external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous...... plasma. In this study, we are presenting the surface modification"pf polymers by plasma polymerization using Softplasma™. Softplasma™ can be used for two major types of polymerization: polymerization of vinyl monomers, where plasma acts as initiator; chemical vapour deposition, where plasma acts...

  12. STUDY ON RELATIVE ABUNDANCE OF Plasmodium SPECIES: A ...

    African Journals Online (AJOL)

    DR. AMINU

    2013-06-01

    Jun 1, 2013 ... Keywords: abundance, plasmodium, relative, thin blood film, malaria control programmes. INTRODUCTION ... When an infected female Anopheles mosquito bites a ... the understanding of the type of infection as well as.

  13. Relative Abundance of Breeding Birds in the Dismal Swamp 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To obtain an idea of the relative abundance of breeding birds in the predominant mixed swamp hardwoods forest of the Dismal Swamp in southeastern Virginia, a...

  14. Unit scale abundance and habitat data - Calawah River Riverscape Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The objective of this study was to identify the patterns of juvenile salmonid distribution and relative abundance in relation to habitat correlates. It is the first...

  15. Whooping Crane Winter Abundance Survey Protocol Aransas National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This protocol is primarily designed to provide a mechanism for monitoring trends in whooping crane abundance on their wintering grounds along the Texas gulf coast....

  16. Fundamental constraints on the abundances of chemotaxis proteins

    CERN Document Server

    Bitbol, Anne-Florence

    2015-01-01

    Flagellated bacteria, such as Escherichia coli, perform directed motion in gradients of concentration of attractants and repellents in a process called chemotaxis. The E. coli chemotaxis signaling pathway is a model for signal transduction, but it has unique features. We demonstrate that the need for fast signaling necessitates high abundances of the proteins involved in this pathway. We show that further constraints on the abundances of chemotaxis proteins arise from the requirements of self-assembly, both of flagellar motors and of chemoreceptor arrays. All these constraints are specific to chemotaxis, and published data confirm that chemotaxis proteins tend to be more highly expressed than their homologs in other pathways. Employing a chemotaxis pathway model, we show that the gain of the pathway at the level of the response regulator CheY increases with overall chemotaxis protein abundances. This may explain why, at least in one E. coli strain, the abundance of all chemotaxis proteins is higher in media w...

  17. Protein abundance profiling of the Escherichia coli cytosol

    DEFF Research Database (Denmark)

    Ishihama, Y.; Schmidt, T.; Rappsilber, J.

    2008-01-01

    Background: Knowledge about the abundance of molecular components is an important prerequisite for building quantitative predictive models of cellular behavior. Proteins are central components of these models, since they carry out most of the fundamental processes in the cell. Thus far, protein...... sample. Using a combination of LC-MS/MS approaches with protein and peptide fractionation steps we identified 1103 proteins from the cytosolic fraction of the Escherichia coli strain MC4100. A measure of abundance is presented for each of the identified proteins, based on the recently developed em......PAI approach which takes into account the number of sequenced peptides per protein. The values of abundance are within a broad range and accurately reflect independently measured copy numbers per cell. As expected, the most abundant proteins were those involved in protein synthesis, most notably ribosomal...

  18. The RAVE Catalog of Stellar Elemental Abundances: First Data Release

    NARCIS (Netherlands)

    Boeche, C.; Siebert, A.; Williams, M.; de Jong, R. S.; Steinmetz, M.; Fulbright, J. P.; Ruchti, G. R.; Bienaymé, O.; Bland-Hawthorn, J.; Campbell, R.; Freeman, K. C.; Gibson, B. K.; Gilmore, G.; Grebel, E. K.; Helmi, A.; Munari, U.; Navarro, J. F.; Parker, Q. A.; Reid, W.; Seabroke, G. M.; Siviero, A.; Watson, F. G.; Wyse, R. F. G.; Zwitter, T.

    2011-01-01

    We present chemical elemental abundances for 36,561 stars observed by the RAdial Velocity Experiment (RAVE), an ambitious spectroscopic survey of our Galaxy at Galactic latitudes |b| > 25° and with magnitudes in the range 9

  19. THE ATOMIC WEIGHTS COMMISSION AND ISOTOPIC ABUNDANCE RATIO DETERMINATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    HOLDEN, N.E.

    2005-08-07

    Following Thomson's discovery of stable isotopes in non-radioactive chemical elements, the derivation of atomic weight values from mass spectrometric measurements of isotopic abundance ratios moved very slowly. Forty years later, only 3 1/2 % of the recommended values were based on mass spectrometric measurements and only 38% in the first half century. It might be noted that two chemical elements (tellurium and mercury) are still based on chemical measurements, where the atomic weight value calculated from the relative isotopic abundance measurement either agrees with the value from the chemical measurement or the atomic weight value calculated from the relative isotopic abundance measurement falls within the uncertainty of the chemical measurement of the atomic weight. Of the 19 chemical elements, whose atomic weight is based on non-corrected relative isotopic abundance measurements, five of these are two isotope systems (indium, iridium, lanthanum, lutetium and tantalum) and one is a three-isotope system (oxygen).

  20. Abundance of Asymmetric Dark Matter in Brane World Cosmology

    Science.gov (United States)

    Abdusattar, Haximjan; Iminniyaz, Hoernisa

    2016-09-01

    Relic abundance of asymmetric Dark Matter particles in brane world cosmological scenario is investigated in this article. Hubble expansion rate is enhanced in brane world cosmology and it affects the relic abundance of asymmetric Dark Matter particles. We analyze how the relic abundance of asymmetric Dark Matter is changed in this model. We show that in such kind of nonstandard cosmological scenario, indirect detection of asymmetric Dark Matter is possible if the cross section is small enough which let the anti-particle abundance kept in the same amount with the particle. We show the indirect detection signal constraints can be used to such model only when the cross section and the 5-dimensional Planck mass scale are in appropriate values. Supported by the National Natural Science Foundation of China under Grant No. 11365022

  1. Composition, Abundance and Seasonality of Zooplankton in Mida ...

    African Journals Online (AJOL)

    Daisy Ouya

    Key words: zooplankton, phytoplankton, composition, abundance, diversity, Mida creek, ..... estuaries in India, accelerated zooplankton ... plankton processes have a faster time frame. It is ... Okemwa, E.N. (1989) Analysis of six 24 hours series.

  2. A Comparison of Stellar Elemental Abundance Techniques and Measurements

    CERN Document Server

    Hinkel, Natalie R; Pagano, Michael D; Desch, Steven J; Anbar, Ariel D; Adibekyan, Vardan; Blanco-Cuaresma, Sergi; Carlberg, Joleen K; Mena, Elisa Delgado; Liu, Fan; Nordlander, Thomas; Sousa, Sergio G; Korn, Andreas; Gruyters, Pieter; Heiter, Ulrike; Jofre, Paula; Santos, Nuno C; Soubiran, Caroline

    2016-01-01

    Stellar elemental abundances are important for understanding the fundamental properties of a star or stellar group, such as age and evolutionary history, as well as the composition of an orbiting planet. However, as abundance measurement techniques have progressed, there has been little standardization between individual methods and their comparisons. As a result, different stellar abundance procedures determine measurements that vary beyond quoted error for the same elements within the same stars (Hinkel et al. 2014). The purpose of this paper is to better understand the systematic variations between methods and offer recommendations for producing more accurate results in the future. We have invited a number of participants from around the world (Australia, Portugal, Sweden, Switzerland, and USA) to calculate ten element abundances (C, O, Na, Mg, Al, Si, Fe, Ni, Ba, and Eu) using the same stellar spectra for four stars (HD361, HD10700, HD121504, HD202206). Each group produced measurements for each of the sta...

  3. 1 Species Diversity and Relative Abundance.cdr

    African Journals Online (AJOL)

    Administrator

    The diversity and relative species abundance of fisheries resources were studied from Winneba to Cape Coast on ... method, which is used all year round (MoFA, .... 49. Thunnus sp. Tuna. *. 50. Sepiidae. Sepia officinalis. Common cuttlefish.

  4. Relative abundance of sweetpotato whitefly in orange-fleshed ...

    African Journals Online (AJOL)

    ACSS

    Relative abundance of sweetpotato whitefly in orange-fleshed sweetpotato cultivars .... 8, 9 and 10. Table 1. Ecological factors and study condition of location (Umudike) in Nigeria (2010 and ..... approaches to Human Nutritional. Deficiencies.

  5. Determining the forsterite abundance of the dust around AGB stars

    CERN Document Server

    de Vries, B L; Waters, L B F M; Blommaert, J A D L; Kemper, F

    2010-01-01

    We present a diagnostic tool to determine the forsterite abundance of the dust ejected by AGB stars. Our method is based on a comparison between the observed strength of spectral bands of forsterite and model calculations. We show that the 11.3 {\\mu}m forsterite band is a robust indicator of the forsterite abundance of the current mass-loss period for AGB stars with an optically thick dust shell. The 33.6 {\\mu}m band of forsterite is sensitive to changes in the density and the geometry of the emitting dust shell, and so a less robust indicator. We apply this method to six high mass-loss rate AGB stars, showing that AGB stars can have forsterite abundances of 12% by mass and higher, which is more than the previously found maximum abundance of 5%.

  6. Understanding and reducing statistical uncertainties in nebular abundance determinations

    CERN Document Server

    Wesson, R; Scicluna, P

    2012-01-01

    Whenever observations are compared to theories, an estimate of the uncertainties associated with the observations is vital if the comparison is to be meaningful. However, many determinations of temperatures, densities and abundances in photoionized nebulae do not quote the associated uncertainty. Those that do typically propagate the uncertainties using analytical techniques which rely on assumptions that generally do not hold. Motivated by this issue, we have developed NEAT (Nebular Empirical Analysis Tool), a new code for calculating chemical abundances in photoionized nebulae. The code carries out an analysis of lists of emission lines using long-established techniques to estimate the amount of interstellar extinction, calculate representative temperatures and densities, compute ionic abundances from both collisionally excited lines and recombination lines, and finally to estimate total elemental abundances using an ionization correction scheme. NEAT uses a Monte Carlo technique to robustly propagate uncer...

  7. Factors affecting the distribution, abundance and diversity of rock ...

    African Journals Online (AJOL)

    between the physical characteristics of the pools and the distribu- tion, abundance and ... Factors regulating density and species composition of rock- pool fish ...... Morphological adaptations that enable intertidal fish to resist turbulence have ...

  8. Relative abundance of desert tortoises on the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Rautenstrauch, K.R.; O`Farrell, T.P.

    1993-12-31

    Seven hundred fifty-nine transects having a total length of 1,191 km were walked during 1981--1986 to determine the distribution and relative abundance of desert tortoises (Gopherus agassizii) on the Nevada Test Site (NTS). The abundance of tortoises on NTS was low to very low relative to other populations in the Mojave Desert. Sign of tortoises was found from 880 to 1,570 m elevation and was more abundant above 1,200 m than has been reported previously for Nevada. Tortoises were more abundant on NTS on the upper alluvial fans and slopes of mountains than in valley bottoms. They also were more common on or near limestone and dolomite mountains than on mountains of volcanic origin.

  9. FAMA: An automatic code for stellar parameter and abundance determination

    CERN Document Server

    Magrini, Laura; Friel, Eileen; Spina, Lorenzo; Jacobson, Heather; Cantat-Gaudin, Tristan; Donati, Paolo; Baglioni, Roberto; Maiorca, Enrico; Bragaglia, Angela; Sordo, Rosanna; Vallenari, Antonella

    2013-01-01

    The large amount of spectra obtained during the epoch of extensive spectroscopic surveys of Galactic stars needs the development of automatic procedures to derive their atmospheric parameters and individual element abundances. Starting from the widely-used code MOOG by C. Sneden, we have developed a new procedure to determine atmospheric parameters and abundances in a fully automatic way. The code FAMA (Fast Automatic MOOG Analysis) is presented describing its approach to derive atmospheric stellar parameters and element abundances. The code, freely distributed, is written in Perl and can be used on different platforms. The aim of FAMA is to render the computation of the atmospheric parameters and abundances of a large number of stars using measurements of equivalent widths as automatic and as independent of any subjective approach as possible. It is based on the simultaneous search for three equilibria: excitation equilibrium, ionization balance, and the relationship between \\fei\\ and the reduced equivalent ...

  10. Amphibian abundance and diversity in Meru National Park, Kenya

    NARCIS (Netherlands)

    Wasonga, D.V.; Bakele, A.; Lötters, S.; Balakrishnan, M.

    2007-01-01

    The diversity and abundance of amphibians were investigated in Meru National Park, Kenya, using transect sampling, drift-fence and pitfall trapping and opportunistic collecting. A total of 430 individuals under seven genera (Amietophrynus, Hemisus, Hyperolius, Phrynobatrachus, Phrynomantis,

  11. Solar models with new low-metal abundances

    CERN Document Server

    Yang, Wuming

    2016-01-01

    In the last decade, the photospheric abundances of the Sun had been revised several times by many observers. The standard solar models (SSM) constructed with the new low-metal abundances disagree with helioseismic results and detected neutrino fluxes. The solar model problem has been puzzled some stellar physicists for more than ten years. Rotation, enhanced diffusion, convection overshoot, and magnetic fields are used to reconcile the new abundances with helioseismology. The \\textbf{too} low-helium \\textbf{subsurface abundance} in enhanced diffusion models can be improved by the mixing caused by rotation and magnetic fields. The problem of the depth of the convective zone in rotating models can be resolved by convection overshoot. Consequently the Asplund-Grevesse-Sauval rotation model including overshooting (AGSR) reproduces the seismically inferred sound-speed and density profiles, and the convection zone depth as well as the Grevesse and Sauval (GS98) model computed before. But this model fails to reprodu...

  12. Abundances of PNe in the Outer Disk of M31

    CERN Document Server

    Kwitter, Karen B; Balick, Bruce; Henry, R B C

    2012-01-01

    We present spectroscopic observations and chemical abundances of 16 planetary nebulae (PNe) in the outer disk of M31. The [O III] 4363 line is detected in all objects, allowing a direct measurement of the nebular temperature essential for accurate abundance determinations. Our results show that the abundances in these M31 PNe display the same correlations and general behaviors as Type II PNe in the Milky Way Galaxy. We also calculate photoionization models to derive estimates of central star properties. From these we infer that our sample PNe, all near the peak of the Planetary Nebula Luminosity Function, originated from stars near 2 M_sun. Finally, under the assumption that these PNe are located in M31's disk, we plot the oxygen abundance gradient, which appears shallower than the gradient in the Milky Way.

  13. IgG4 related sclerosing mastitis: expanding the morphological spectrum of IgG4 related diseases.

    Science.gov (United States)

    Chougule, Abhijit; Bal, Amanjit; Das, Ashim; Singh, Gurpreet

    2015-01-01

    IgG4 related disease (IgG4RD) is a recently recognised condition characterised by mass forming lesions associated with storiform fibrosis, obliterative phlebitis, lymphoplasmacytic infiltrate rich in IgG4 positive plasma cells and elevated serum IgG4 levels. Although rare, mammary involvement has been reported as IgG4 related sclerosing mastitis, the morphological counterpart of a growing family of IgG4 related diseases. A total of 17 cases belonging to mass forming benign inflammatory breast lesions such as plasma cell mastitis, granulomatous lobular mastitis, non-specific mastitis and inflammatory pseudotumour were investigated as a possible member of IgG4 related sclerosing mastitis. Clinical, radiological, histopathological and immunohistochemistry findings were noted in all cases. Cases diagnosed as inflammatory pseudotumour showed all the histopathological features of IgG4RD along with increased number of IgG4 positive plasma cells and IgG4/IgG ratio >40%. However, only a few IgG4 positive cells were seen in plasma cell mastitis, granulomatous lobular mastitis and non-specific mastitis cases. These cases also did not fulfill the morphological criteria for the diagnosis of IgG4 related diseases. IgG4RD should be excluded in plasma cell rich lesions diagnosed on core biopsies by IgG4 immunostaining. This can avoid unnecessary surgery as IgG4 related diseases respond to simple and effective steroid treatment.

  14. Protein abundance profiling of the Escherichia coli cytosol

    Directory of Open Access Journals (Sweden)

    Mann Matthias

    2008-02-01

    Full Text Available Abstract Background Knowledge about the abundance of molecular components is an important prerequisite for building quantitative predictive models of cellular behavior. Proteins are central components of these models, since they carry out most of the fundamental processes in the cell. Thus far, protein concentrations have been difficult to measure on a large scale, but proteomic technologies have now advanced to a stage where this information becomes readily accessible. Results Here, we describe an experimental scheme to maximize the coverage of proteins identified by mass spectrometry of a complex biological sample. Using a combination of LC-MS/MS approaches with protein and peptide fractionation steps we identified 1103 proteins from the cytosolic fraction of the Escherichia coli strain MC4100. A measure of abundance is presented for each of the identified proteins, based on the recently developed emPAI approach which takes into account the number of sequenced peptides per protein. The values of abundance are within a broad range and accurately reflect independently measured copy numbers per cell. As expected, the most abundant proteins were those involved in protein synthesis, most notably ribosomal proteins. Proteins involved in energy metabolism as well as those with binding function were also found in high copy number while proteins annotated with the terms metabolism, transcription, transport, and cellular organization were rare. The barrel-sandwich fold was found to be the structural fold with the highest abundance. Highly abundant proteins are predicted to be less prone to aggregation based on their length, pI values, and occurrence patterns of hydrophobic stretches. We also find that abundant proteins tend to be predominantly essential. Additionally we observe a significant correlation between protein and mRNA abundance in E. coli cells. Conclusion Abundance measurements for more than 1000 E. coli proteins presented in this work

  15. Plasmas for medicine

    Science.gov (United States)

    von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.

    2013-09-01

    Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous

  16. Nonlinear Plasma Wave in Magnetized Plasmas

    CERN Document Server

    Bulanov, Sergei V; Kando, Masaki; Koga, James K; Hosokai, Tomonao; Zhidkov, Alexei G; Kodama, Ryosuke

    2013-01-01

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic "Four-Ray Star" pattern which has been observed in the image of the electron bunch in experiments [T. Hosokai, et al., Phys. Rev. Lett. 97, 075004 (2006)].

  17. The Open Cluster Chemical Abundances from Spanish Observatories Survey (OCCASO)

    Science.gov (United States)

    Carrera, R.; Casamiquela, L.; Balaguer-Núñez, L.; Jordi, C.; Pancino, E.; Allende-Prieto, C.; Blanco-Cuaresma, S.; Martínez-Vázquez, C. E.; Murabito, S.; del Pino, A.; Aparicio, A.; Gallart, C.; Recio-Blanco, A.

    2016-10-01

    We present the motivation, design and current status of the Open Cluster Chemical Abundances from Spanish Observatories survey (OCCASO). Using the high resolution spectroscopic facilities available at Spanish observatories, OCCASO will derive chemical abundances in a sample of 20 to 25 OCs older than 0.5 Gyr. This sample will be used to study in detail the formation and evolution of the Galactic disk using OCs as tracers.

  18. The Open Cluster Chemical Abundances from Spanish Observatories survey (OCCASO)

    CERN Document Server

    Carrera, R; Balaguer-Núñez, L; Jordi, C; Pancino, E; Allende-Prieto, C; Blanco-Cuaresma, S; Mártinez-Vázquez, C E; Murabito, S; del Pino, A; Aparicio, A; Gallart, C; Recio-Blanco, A

    2014-01-01

    We present the motivation, design and current status of the Open Cluster Chemical Abundances from Spanish Observatories survey (OCCASO). Using the high resolution spectroscopic facilities available at Spanish observatories, OCCASO will derive chemical abundances in a sample of 20 to 25 open clusters older than 0.5 Gyr. This sample will be used to study in detail the formation and evolution of the Galactic disc using open clusters as tracers.

  19. Beryllium, Lithium and Oxygen Abundances in F-type Stars

    CERN Document Server

    García-López, R J; Pérez de Taoro, M R; Casares, C; Rasilla, J L; Rebolo, R; Allende-Prieto, C

    1997-01-01

    Beryllium and oxygen abundances have been derived in a sample of F-type field stars for which lithium abundances had been measured previously, with the aim of obtaining observational constraints to discriminate between the different mixing mechanisms proposed. Mixing associated with the transport of angular momentum in the stellar interior and internal gravity waves within the framework of rotating evolutionary models, appear to be promising ways to explain the observations.

  20. Harbour porpoise Phocoena phocoena abundance in the southwestern Baltic Sea

    OpenAIRE

    Scheidat, M.; Gilles, A.; Kock, K. H.; Siebert, U

    2008-01-01

    Harbour porpoise Phocoena phocoena is the only cetacean species resident in the Baltic Sea. At least 2 different subpopulations occur in this area, with a presumed demarcation line in the western Baltic Sea. Aerial surveys were conducted during different seasons in the years 2002 to 2006, to obtain estimates of porpoise abundance for the southwestern Baltic. Within the survey area, 3 strata were defined. In total, 46 surveys were completed for these strata. Abundance estimates and correspondi...

  1. A Differential Abundance Analysis of HD219175 A and B

    Institute of Scientific and Technical Information of China (English)

    Hua-Wei Zhang; Gang Zhao

    2005-01-01

    The abundances of the wide binary pair HD 219175 A and B are determined and compared using a line-by-line differential analysis. No evidence for difference has been found in the abundances of Fe, O, Na, Mg, Al, Si, K, Ca, Sc,Ti, V, Cr, Mn, Ni, Cu and Ba. Our results support a physical relation between the two components of HD 219175.

  2. New Abundant Microbial Groups in Aquatic Hypersaline Environments

    OpenAIRE

    Ghai, Rohit; Pašić, Lejla; Fernández González, Ana Beatriz; Martín Cuadrado, Ana Belén; Megumi Mizuno, Carolina; McMahon, Katherine D.; Papke, R Thane; Stepanauskas, Ramunas; Rodríguez Brito, Beltrán; Rohwer, Forest; Sánchez-Porro Álvarez, Cristina; Ventosa Ucero, Antonio; Rodríguez Valera, Francisco

    2011-01-01

    We describe the microbiota of two hypersaline saltern ponds, one of intermediate salinity (19%) and a NaCl saturated crystallizer pond (37%) using pyrosequencing. The analyses of these metagenomes (nearly 784 Mb) reaffirmed the vast dominance of Haloquadratum walsbyi but also revealed novel, abundant and previously unsuspected microbial groups. We describe for the first time, a group of low GC Actinobacteria, related to freshwater Actinobacteria, abundant in low and intermediate salinities. M...

  3. Literature survey of isotopic abundance data for 1987-1989

    Energy Technology Data Exchange (ETDEWEB)

    Holden, N.E. (Brookhaven National Lab., Upton, NY (USA))

    1989-08-09

    I have compiled all of the data on isotopic abundance measurements and their variation in nature for the time period since the last General Assembly. Most of the data deals with the variations in the abundances as given by per mil deviations from some standard. As such, they are not of major interest to the Atomic Weights Commission. However, there were some measurements which are of general interest in this list.

  4. Causality of the relationship between geographic distribution and species abundance

    DEFF Research Database (Denmark)

    Borregaard, Michael Krabbe; Rahbek, Carsten

    2010-01-01

    The positive relationship between a species' geographic distribution and its abundance is one of ecology's most well-documented patterns, yet the causes behind this relationship remain unclear. Although many hypotheses have been proposed to account for distribution-abundance relationships none ha......, in a framework that facilitates a comparison between them. We identify and discuss the central factors governing the individual mechanisms, and elucidate their effect on empirical patterns....

  5. Element Abundances in Solar Energetic Particles and the Solar Corona

    CERN Document Server

    Reames, Donald V

    2013-01-01

    This is a study of abundances of the elements He, C, N, O, Ne, Mg, Si, S, Ar, Ca, and Fe in solar energetic particles (SEPs) in the 2 - 15 MeV amu-1 region measured on the Wind spacecraft during 54 large SEP events occurring between November 1994 and June 2012. The origin of most of the temporal and spatial variations in abundances of the heavier elements lies in rigidity-dependent scattering during transport of the particles away from the site of acceleration at shock waves driven out from the Sun by coronal mass ejections (CMEs). Variation in the abundance of Fe is correlated with the Fe spectral index, as expected from scattering theory but not previously noted. Clustering of Fe abundances during the "reservoir" period, late in SEP events, is also newly reported. Transport-induced enhancements in one region are balanced by depletions in another, thus, averaging over these variations produces SEP abundances that are energy independent, confirms previous SEP abundances in this energy region, and provides a c...

  6. On ribosome load, codon bias and protein abundance.

    Directory of Open Access Journals (Sweden)

    Stefan Klumpp

    Full Text Available Different codons encoding the same amino acid are not used equally in protein-coding sequences. In bacteria, there is a bias towards codons with high translation rates. This bias is most pronounced in highly expressed proteins, but a recent study of synthetic GFP-coding sequences did not find a correlation between codon usage and GFP expression, suggesting that such correlation in natural sequences is not a simple property of translational mechanisms. Here, we investigate the effect of evolutionary forces on codon usage. The relation between codon bias and protein abundance is quantitatively analyzed based on the hypothesis that codon bias evolved to ensure the efficient usage of ribosomes, a precious commodity for fast growing cells. An explicit fitness landscape is formulated based on bacterial growth laws to relate protein abundance and ribosomal load. The model leads to a quantitative relation between codon bias and protein abundance, which accounts for a substantial part of the observed bias for E. coli. Moreover, by providing an evolutionary link, the ribosome load model resolves the apparent conflict between the observed relation of protein abundance and codon bias in natural sequences and the lack of such dependence in a synthetic gfp library. Finally, we show that the relation between codon usage and protein abundance can be used to predict protein abundance from genomic sequence data alone without adjustable parameters.

  7. Spectral Unmixing Based Construction of Lunar Mineral Abundance Maps

    Science.gov (United States)

    Bernhardt, V.; Grumpe, A.; Wöhler, C.

    2017-07-01

    In this study we apply a nonlinear spectral unmixing algorithm to a nearly global lunar spectral reflectance mosaic derived from hyper-spectral image data acquired by the Moon Mineralogy Mapper (M3) instrument. Corrections for topographic effects and for thermal emission were performed. A set of 19 laboratory-based reflectance spectra of lunar samples published by the Lunar Soil Characterization Consortium (LSCC) were used as a catalog of potential endmember spectra. For a given spectrum, the multi-population population-based incremental learning (MPBIL) algorithm was used to determine the subset of endmembers actually contained in it. However, as the MPBIL algorithm is computationally expensive, it cannot be applied to all pixels of the reflectance mosaic. Hence, the reflectance mosaic was clustered into a set of 64 prototype spectra, and the MPBIL algorithm was applied to each prototype spectrum. Each pixel of the mosaic was assigned to the most similar prototype, and the set of endmembers previously determined for that prototype was used for pixel-wise nonlinear spectral unmixing using the Hapke model, implemented as linear unmixing of the single-scattering albedo spectrum. This procedure yields maps of the fractional abundances of the 19 endmembers. Based on the known modal abundances of a variety of mineral species in the LSCC samples, a conversion from endmember abundances to mineral abundances was performed. We present maps of the fractional abundances of plagioclase, pyroxene and olivine and compare our results with previously published lunar mineral abundance maps.

  8. Chemical abundances from planetary nebulae in local spiral galaxies

    CERN Document Server

    Richer, M G

    2015-01-01

    While the chemical abudances observed in bright planetary nebulae in local spiral galaxies are less varied than their counterparts in dwarfs, they provide new insight. Their helium abundances are typically enriched by less than 50\\% compared to the primordial abundance. Nitrogen abundances always show some level of secondary enrichment, but the absolute enrichment is not extreme. In particular, type I PNe are rare among the bright PNe in local spirals. The oxygen and neon abundances are very well correlated and follow the relation between these abundances observed in star-forming galaxies, implying that either the progenitor stars of these PNe modify neither abundance substantially or that they modify both to maintain the ratio (not predicted by theory). According to theory, these results imply that the progenitor stars of bright PNe in local spirals have masses of about $2\\,\\mathrm M_{\\odot}$ or less. If so, the progenitors of these PNe have substantial lifetimes that allow us to use them to study the recent...

  9. CHROMOSPHERIC MODELS AND THE OXYGEN ABUNDANCE IN GIANT STARS

    Energy Technology Data Exchange (ETDEWEB)

    Dupree, A. K.; Avrett, E. H.; Kurucz, R. L., E-mail: dupree@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2016-04-10

    Realistic stellar atmospheric models of two typical metal-poor giant stars in Omega Centauri, which include a chromosphere (CHR), influence the formation of optical lines of O i: the forbidden lines (λ6300, λ6363) and the infrared triplet (λλ7771−7775). One-dimensional semi-empirical non-local thermodynamic equilibrium (LTE) models are constructed based on observed Balmer lines. A full non-LTE formulation is applied for evaluating the line strengths of O i, including photoionization by the Lyman continuum and photoexcitation by Lyα and Lyβ. Chromospheric models (CHR) yield forbidden oxygen transitions that are stronger than those in radiative/convective equilibrium (RCE) models. The triplet oxygen lines from high levels also appear stronger than those produced in an RCE model. The inferred oxygen abundance from realistic CHR models for these two stars is decreased by factors of ∼3 as compared to values derived from RCE models. A lower oxygen abundance suggests that intermediate-mass AGB stars contribute to the observed abundance pattern in globular clusters. A change in the oxygen abundance of metal-poor field giants could affect models of deep mixing episodes on the red giant branch. Changes in the oxygen abundance can impact other abundance determinations that are critical to astrophysics, including chemical tagging techniques and galactic chemical evolution.

  10. Abundance profiles and cool cores in galaxy groups

    CERN Document Server

    Johnson, Ria; Ponman, Trevor J; Rasmussen, Jesper; Sanderson, Alastair J R

    2011-01-01

    Using data from the Two Dimensional XMM-Newton Group Survey (2dXGS), we have examined the abundance profile properties of both cool core (CC) and non cool core (NCC) galaxy groups. The ten NCC systems in our sample represent a population which to date has been poorly studied in the group regime. Fitting the abundance profiles as a linear function of log radius, we find steep abundance gradients in cool core (CC) systems, with a slope of -0.54+/-0.07. In contrast, non cool core (NCC) groups have profiles consistent with uniform metallicity. Many CC groups show a central abundance dip or plateau, and we find evidence for anticorrelation between the core abundance gradient and the 1.4 GHz radio power of the brightest group galaxy (BGG) in CC systems. This may indicate the effect of AGN-driven mixing within the central ~0.1r_500. It is not possible to discern whether such behaviour is present in the NCC groups, due to the small and diverse sample with the requisite radio data. The lack of strong abundance gradien...

  11. Chromospheric Models and the Oxygen Abundance in Giant Stars

    Science.gov (United States)

    Dupree, A. K.; Avrett, E. H.; Kurucz, R. L.

    2016-04-01

    Realistic stellar atmospheric models of two typical metal-poor giant stars in Omega Centauri, which include a chromosphere (CHR), influence the formation of optical lines of O i: the forbidden lines (λ6300, λ6363) and the infrared triplet (λλ7771-7775). One-dimensional semi-empirical non-local thermodynamic equilibrium (LTE) models are constructed based on observed Balmer lines. A full non-LTE formulation is applied for evaluating the line strengths of O i, including photoionization by the Lyman continuum and photoexcitation by Lyα and Lyβ. Chromospheric models (CHR) yield forbidden oxygen transitions that are stronger than those in radiative/convective equilibrium (RCE) models. The triplet oxygen lines from high levels also appear stronger than those produced in an RCE model. The inferred oxygen abundance from realistic CHR models for these two stars is decreased by factors of ˜3 as compared to values derived from RCE models. A lower oxygen abundance suggests that intermediate-mass AGB stars contribute to the observed abundance pattern in globular clusters. A change in the oxygen abundance of metal-poor field giants could affect models of deep mixing episodes on the red giant branch. Changes in the oxygen abundance can impact other abundance determinations that are critical to astrophysics, including chemical tagging techniques and galactic chemical evolution.

  12. Carbon and Strontium Abundances of Metal-Poor Stars

    CERN Document Server

    Lai, David K; Bolte, Michael; Lucatello, Sara

    2007-01-01

    We present carbon and strontium abundances for 100 metal-poor stars measured from R$\\sim $7000 spectra obtained with the Echellette Spectrograph and Imager at the Keck Observatory. Using spectral synthesis of the G-band region, we have derived carbon abundances for stars ranging from [Fe/H]$=-1.3$ to [Fe/H]$=-3.8$. The formal errors are $\\sim 0.2$ dex in [C/Fe]. The strontium abundance in these stars was measured using spectral synthesis of the resonance line at 4215 {\\AA}. Using these two abundance measurments along with the barium abundances from our previous study of these stars, we show it is possible to identify neutron-capture-rich stars with our spectra. We find, as in other studies, a large scatter in [C/Fe] below [Fe/H]$ = -2$. Of the stars with [Fe/H]$<-2$, 9$\\pm$4% can be classified as carbon-rich metal-poor stars. The Sr and Ba abundances show that three of the carbon-rich stars are neutron-capture-rich, while two have normal Ba and Sr. This fraction of carbon enhanced stars is consistent with ...

  13. The abundance of silicon in the solar atmosphere

    Science.gov (United States)

    Shaltout, A. M. K.; Beheary, M. M.; Bakry, A.; Ichimoto, K.

    2013-04-01

    High-resolution solar spectra were used to determine the silicon abundance (εSi) content by comparison with Si line synthesis relying on realistic hydrodynamical simulations of the solar surface convection, as 3D inhomogeneous model of the solar photosphere. Based on a set of 19 Si I and 2 Si II lines, with accurate transition probabilities as well as accurate observational data available, the solar photospheric Si abundance has been determined to be log εSi(3D) = 7.53 ± 0.07. Here we derive the photospheric silicon abundance taking into account non-LTE effects based on 1D solar model, the non-LTE abundance value we find is log εSi (1D) = 7.52 ± 0.08. The photospheric Si abundance agrees well with the results of Asplund and more recently published by Asplund et al. relative to previous 3D-based abundances, the consistency given that the quoted errors here are (±0.07 dex).

  14. New calibrations for abundance determinations in HII regions

    CERN Document Server

    Pilyugin, L S

    2016-01-01

    Simple relations for deriving the oxygen abundance in HII regions with intensities of the three strong emission lines R_2, R_3, and N_2 (R calibration) or S_2, R_3, and N_2 (S calibration) in their spectra are suggested. A sample of 313 reference HII regions of the counterpart method is used as calibrating data points. Relations for the determination of nitrogen abundances, the R calibration, are also constructed. We find that the oxygen and nitrogen abundances in high-metallicity HII regions can be estimated using the intensities of the two strong lines R_2 and N_2 (or S_2 and N_2 for oxygen) only. The corresponding two-dimensional relations are provided. There are considerable advantages of the suggested calibration relations as compared to the existing ones. First, the oxygen and nitrogen abundances estimated through the suggested calibrations agree with the Te-based abundances within ~0.1 dex over the whole metallicity range, i.e., the relative accuracy of the calibration-based abundances is 0.1 dex. Alth...

  15. Global abundance of planktonic heterotrophic protists in the deep ocean.

    Science.gov (United States)

    Pernice, Massimo C; Forn, Irene; Gomes, Ana; Lara, Elena; Alonso-Sáez, Laura; Arrieta, Jesus M; del Carmen Garcia, Francisca; Hernando-Morales, Victor; MacKenzie, Roy; Mestre, Mireia; Sintes, Eva; Teira, Eva; Valencia, Joaquin; Varela, Marta M; Vaqué, Dolors; Duarte, Carlos M; Gasol, Josep M; Massana, Ramon

    2015-03-01

    The dark ocean is one of the largest biomes on Earth, with critical roles in organic matter remineralization and global carbon sequestration. Despite its recognized importance, little is known about some key microbial players, such as the community of heterotrophic protists (HP), which are likely the main consumers of prokaryotic biomass. To investigate this microbial component at a global scale, we determined their abundance and biomass in deepwater column samples from the Malaspina 2010 circumnavigation using a combination of epifluorescence microscopy and flow cytometry. HP were ubiquitously found at all depths investigated down to 4000 m. HP abundances decreased with depth, from an average of 72±19 cells ml(-1) in mesopelagic waters down to 11±1 cells ml(-1) in bathypelagic waters, whereas their total biomass decreased from 280±46 to 50±14 pg C ml(-1). The parameters that better explained the variance of HP abundance were depth and prokaryote abundance, and to lesser extent oxygen concentration. The generally good correlation with prokaryotic abundance suggested active grazing of HP on prokaryotes. On a finer scale, the prokaryote:HP abundance ratio varied at a regional scale, and sites with the highest ratios exhibited a larger contribution of fungi molecular signal. Our study is a step forward towards determining the relationship between HP and their environment, unveiling their importance as players in the dark ocean's microbial food web.

  16. The First-Integral Method and Abundant Explicit Exact Solutions to the Zakharov Equations

    Directory of Open Access Journals (Sweden)

    Yadong Shang

    2012-01-01

    Full Text Available This paper is concerned with the system of Zakharov equations which involves the interactions between Langmuir and ion-acoustic waves in plasma. Abundant explicit and exact solutions of the system of Zakharov equations are derived uniformly by using the first integral method. These exact solutions are include that of the solitary wave solutions of bell-type for n and E, the solitary wave solutions of kink-type for E and bell-type for n, the singular traveling wave solutions, periodic wave solutions of triangle functions, Jacobi elliptic function doubly periodic solutions, and Weierstrass elliptic function doubly periodic wave solutions. The results obtained confirm that the first integral method is an efficient technique for analytic treatment of a wide variety of nonlinear systems of partial differential equations.

  17. The Detectability of Neon Fluorescence and Measurement of the Solar Photospheric Neon Abundance

    CERN Document Server

    Drake, Jeremy J

    2007-01-01

    Monte Carlo calculations of the Ne K$\\alpha$ line fluoresced by coronal x-rays and emitted near the temperature minimum region of the solar atmosphere have been employed to investigate the use of this feature to measure directly the solar photospheric Ne abundance. Though very weak, comparison with spectral line databases indicates that at plasma temperatures typical of the quiet Sun and cool active regions ($\\leq 2\\times 10^6$ K) the line is isolated and unblended. A canonical solar chemical composition yields an equivalent width of $\\sim 6$ m\\AA (0.3 eV) when observed at heliocentric angles $\\sim 0$. For a 1 arcmin field of view, photon fluxes at Earth are of order 0.2 ph s$^{-1}$ for the quiet Sun, rendering the Ne K$\\alpha$ fluorescent line a quite feasible means for determining the solar photospheric Ne content.

  18. Nontoxic and abundant copper zinc tin sulfide nanocrystals for potential high-temperature thermoelectric energy harvesting.

    Science.gov (United States)

    Yang, Haoran; Jauregui, Luis A; Zhang, Genqiang; Chen, Yong P; Wu, Yue

    2012-02-01

    Improving energy/fuel efficiency by converting waste heat into electricity using thermoelectric materials is of great interest due to its simplicity and reliability. However, many thermoelectric materials are composed of either toxic or scarce elements. Here, we report the experimental realization of using nontoxic and abundant copper zinc tin sulfide (CZTS) nanocrystals for potential thermoelectric applications. The CZTS nanocrystals can be synthesized in large quantities from solution phase reaction and compressed into robust bulk pellets through spark plasma sintering and hot press while still maintaining nanoscale grain size inside. Electrical and thermal measurements have been performed from 300 to 700 K to understand the electron and phonon transports. Extra copper doping during the nanocrystal synthesis introduces a significant improvement in the performance.

  19. Plasma Biomedicine in Orthopedics

    Science.gov (United States)

    Hamaguchi, Satsohi

    2012-10-01

    Various effects of plasmas irradiation on cells, tissues, and biomaterials relevant for orthopedic applications have been examined. For direct application of plasmas to living cells or tissues, dielectric barrier discharges (DBDs) with helium flows into ambient air were used. For biomaterial processing, on the other hand, either helium DBDs mentioned above or low-pressure discharges generated in a chamber were used. In this presentation, plasma effects on cell proliferation and plasma treatment for artificial bones will be discussed. First, the conditions for enhanced cell proliferation in vitro by plasma applications have been examined. The discharge conditions for cell proliferation depend sensitively on cell types. Since cell proliferation can be enhanced even when the cells are cultured in a plasma pre-treated medium, long-life reactive species generated in the medium by plasma application or large molecules (such as proteins) in the medium modified by the plasma are likely to be the cause of cell proliferation. It has been found that there is strong correlation between (organic) hydroperoxide generation and cell proliferation. Second, effects of plasma-treated artificial bones made of porous hydroxyapatite (HA) have been examined in vitro and vivo. It has been found that plasma treatment increases hydrophilicity of the surfaces of microscopic inner pores, which directly or indirectly promotes differentiation of mesenchymal stem cells introduced into the pores and therefore causes faster bone growth. The work has been performed in collaboration with Prof. H. Yoshikawa and his group members at the School of Medicine, Osaka University.

  20. Plasma detachment in linear devices

    Science.gov (United States)

    Ohno, N.

    2017-03-01

    Plasma detachment research in linear devices, sometimes called divertor plasma simulators, is reviewed. Pioneering works exploring the concept of plasma detachment were conducted in linear devices. Linear devices have contributed greatly to the basic understanding of plasma detachment such as volume plasma recombination processes, detached plasma structure associated with particle and energy transport, and other related issues including enhancement of convective plasma transport, dynamic response of plasma detachment, plasma flow reversal, and magnetic field effect. The importance of plasma detachment research using linear devices will be highlighted aimed at the design of future DEMO.

  1. A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars

    CERN Document Server

    Roederer, Ian U; Thompson, Ian B; Shectman, Stephen A; Sneden, Christopher; Burley, Gregory S; Kelson, Daniel D

    2014-01-01

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10-year observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coude Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several ab...

  2. Advanced plasma diagnostics for plasma processing

    Science.gov (United States)

    Malyshev, Mikhail Victorovich

    1999-10-01

    A new, non-intrusive, non-perturbing diagnostic method was developed that can be broadly applied to low pressure, weakly ionized plasmas and glow discharges-trace rare gases optical emission spectroscopy (TRG-OES). The method is based on a comparison of intensities of atomic emission from trace amounts of inert gases (He, Ne, Ar, Kr, and Xe) that are added to the discharge to intensities calculated from the theoretical model. The model assumes a Maxwellian electron energy distribution function (EEDF), computes the population of emitting levels both from the ground state and the metastable states of rare gases, and from the best fit between theory and experiment determines electron temperature (Te). Subject to conditions, TRG-OES can also yield electron density or its upper or lower limit. From the comparison of the emission from levels excited predominantly by high energy electrons to that excited by low energy electrons, information about the EEDF can be obtained. The use of TRG-OES also allows a traditionally qualitative actinometry technique (determination of concentration of radical species in plasma through optical emission) to become a precise quantitative method by including Te and rare gases metastables effects. A combination of TRG-OES, advanced actinometry, and Langmuir probe measurements was applied to several different plasma reactors and regimes of operation. Te measurements and experiments to correct excitation cross section were conducted in a laboratory helical resonator. Two chamber configuration of a commercial (Lam Research) metal etcher were studied to determine the effects of plasma parameters on plasma-induced damage. Two different methods (RF inductive coupling and ultra-high frequency coupling) for generating a plasma in a prototype reactor were also studied. Pulsed plasmas, a potential candidate to eliminate the plasma-induced damage to microelectronics devices that occurs in manufacturing due to differential charging of the wafer, have

  3. Graves' Disease Patients with Persistent Hyperthyroidism and Diffuse Lymphoplasmacytic Infiltration in the Thyroid Show No Histopathological Compatibility with IgG4-Related Disease.

    Directory of Open Access Journals (Sweden)

    Eijun Nishihara

    Full Text Available IgG4-related disease is a novel disease entity characterized by diffuse lymphoplasmacytic infiltration rich in IgG4-positive plasma cells and fibrosis into multiple organs. There is still controversy over whether some thyroid diseases are actually IgG4-related disease. The objective of this study was to elucidate the clinicopathological features of Graves' disease with diffuse lymphoplasmacytic infiltration in the thyroid.Among 1,484 Graves' disease patients who underwent thyroidectomy, we examined their histopathological findings including the degree of lymphoplasmacytic and fibrotic infiltration and levels of IgG4-positive plasma cells in the thyroid. Their clinical pictures were defined by laboratory and ultrasonographic evaluation.A total of 11 patients (0.74% showed diffuse lymphoplasmacytic infiltration in the stroma of the thyroid gland. Meanwhile, other patients showed variable lymphoid infiltration ranging from absent to focally dense but no aggregation of plasma cells in the thyroid gland. Based on the diagnostic criteria of IgG4-related disease, 5 of the 11 subjects had specifically increased levels of IgG4-positive plasma cells in the thyroid. Fibrotic infiltration was present in only 1 patient developing hypothyroidism after anti-thyroid drug treatment for 4 years, but not in the other 10 patients with persistent hyperthyroidism. Obliterative phlebitis was not identified in any of the 11 subjects. Thyroid ultrasound examination showed 1 patient developing hypothyroidism who had diffuse hypoechogenicity, but the other hyperthyroid patients had a coarse echo texture.In our study, Graves' disease patients with persistent hyperthyroidism who had diffuse lymphoplasmacytic infiltration rich in IgG4-positive plasma cells in the thyroid showed no concomitant fibrosis or obliterative phlebitis.

  4. A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars

    Energy Technology Data Exchange (ETDEWEB)

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Burley, Gregory S.; Kelson, Daniel D. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Sneden, Christopher, E-mail: iur@umich.edu [Department of Astronomy, University of Texas at Austin, 1 University Station, C1400, Austin, TX 78712 (United States)

    2014-06-01

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ≈0.25 dex for red giants and ≈0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] ≤–3.5, 84 stars with [Fe/H] ≤–3.0, and 210 stars with [Fe/H] ≤–2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] ≤–2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.

  5. Identification and role of plasma membrane aquaporin in maize root

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Using antiserum against expressed aquaporin fusion protein, GST-RD28, the distribution of aquaporin in the plasma membrane of maize root protoplasts has been examined under confocal laser scanning microscopy by indirect fluorescence staining. Results indicate that there are abundant aquaporins in maize roots, which are distributed in plasma membrane unevenly. Western blotting analysis of total protein solubilized from maize root plasma membrane shows that antiserum against GST-RD28 can cross-react with one protein around 55 ku. Another 28 ku protein can also be detected when the concentration of SDS and DTT in SDS-PAGE sample buffer is increased. The 55 and 28 ku proteins may be dimeric and monomeric of aquaporin respectively. Functional experiments show that aquaporin blocker HgCl2 and aquaporin antiserum can suppress the swelling of maize root protoplasts in hypotonic solution, indicating that aquaporin in plasma membrane of protoplast facilitates rapid transmembrane water flow.

  6. The plasma membrane proteome of germinating barley embryos

    DEFF Research Database (Denmark)

    Hynek, Radovan; Svensson, Birte; Jensen, O.N.

    2009-01-01

    was used to reduce soluble protein contamination and enrich for hydrophobic proteins. Sixty-one proteins in 14 SDS-PAGE bands were identified by LC-MS/MS and database searches. The identifications provide new insight into the plasma membrane functions in seed germination.......Cereal seed germination involves a complex coordination between different seed tissues. Plasma membranes must play crucial roles in coordination and execution of germination; however, very little is known about seed plasma membrane proteomes due to limited tissue amounts combined...... with amphiphilicity and low abundance of membrane proteins. A fraction enriched in plasma membranes was prepared from embryos dissected from 18 h germinated barley seeds using aqueous two-phase partitioning. Reversed-phase chromatography on C-4 resin performed in micro-spin columns with stepwise elution by 2-propanol...

  7. A case of tubulointerstitial nephritis in IgG4-related systemic disease with markedly enlarged kidneys.

    Science.gov (United States)

    Mise, Naobumi; Tomizawa, Yutaka; Fujii, Akiko; Yamaguchi, Yutaka; Sugimoto, Tokuichiro

    2009-06-01

    IgG4-related systemic disease, including autoimmune pancreatitis, is a multi-organ disorder characterized by elevated serum immunoglobulin G4 (IgG4) concentration and IgG4-positive plasma cell infiltration. We report the case of a 67-year-old man with IgG4-related tubulointerstitial nephritis, presenting with markedly enlarged kidneys and renal dysfunction. The serum IgG4 level was elevated with 4200 mg/dl and pathological examination revealed patchy, clearly fringed areas of IgG4-positive plasma cell infiltration and advanced fibrosis in the renal parenchyma, perirenal tissue and lymph nodes. With oral prednisolone at a dose of 60 mg daily, a contraction of the kidneys and an improvement of renal function were observed. No recurrence of the disease was observed during the reduction of prednisolone to 2 mg daily over 4 years.

  8. IgG4-related pleural disease diagnosed by a re-evaluation of chronic bilateral pleuritis in a patient who experienced occasional acute left bacterial pleuritis.

    Science.gov (United States)

    Yamamoto, Hiroshi; Suzuki, Toshiro; Yasuo, Masanori; Kobayashi, Orie; Tsushima, Kenji; Ito, Michiko; Urushihata, Kazuhisa; Yamazaki, Yoshitaka; Hanaoka, Masayuki; Koizumi, Tomonobu; Uehara, Takeshi; Kawakami, Satoshi; Hamano, Hideaki; Kawa, Shigeyuki; Kubo, Keishi

    2011-01-01

    A 78-year-old man with cryptogenic chronic bilateral lymphoplasmacytic pleuritis, diagnosed based on left parietal pleural biopsy specimens obtained by pleuroscopy, developed acute left bacterial pleuritis. The left pleural effusion was neutrophil dominant, however, the right pleural effusion showed lymphoplasmacytic infiltration. Laboratory examinations revealed that his serum IgG4 concentration was increased, with a higher level of IgG4 in the right pleural effusion. Re-evaluation of the previous biopsy specimens using an immunostaining method revealed numerous IgG4-positive plasma cell infiltrations with IgG4-positive/IgG-positive plasma cells at 85.4%. Accordingly, the new diagnosis of this patient was considered to be chronic bilateral IgG4-related pleuritis.

  9. Urban warming drives insect pest abundance on street trees.

    Directory of Open Access Journals (Sweden)

    Emily K Meineke

    Full Text Available Cities profoundly alter biological communities, favoring some species over others, though the mechanisms that govern these changes are largely unknown. Herbivorous arthropod pests are often more abundant in urban than in rural areas, and urban outbreaks have been attributed to reduced control by predators and parasitoids and to increased susceptibility of stressed urban plants. These hypotheses, however, leave many outbreaks unexplained and fail to predict variation in pest abundance within cities. Here we show that the abundance of a common insect pest is positively related to temperature even when controlling for other habitat characteristics. The scale insect Parthenolecanium quercifex was 13 times more abundant on willow oak trees in the hottest parts of Raleigh, NC, in the southeastern United States, than in cooler areas, though parasitism rates were similar. We further separated the effects of heat from those of natural enemies and plant quality in a greenhouse reciprocal transplant experiment. P. quercifex collected from hot urban trees became more abundant in hot greenhouses than in cool greenhouses, whereas the abundance of P. quercifex collected from cooler urban trees remained low in hot and cool greenhouses. Parthenolecanium quercifex living in urban hot spots succeed with warming, and they do so because some demes have either acclimatized or adapted to high temperatures. Our results provide the first evidence that heat can be a key driver of insect pest outbreaks on urban trees. Since urban warming is similar in magnitude to global warming predicted in the next 50 years, pest abundance on city trees may foreshadow widespread outbreaks as natural forests also grow warmer.

  10. Songbird abundance and parasitism differ between urban and rural shrublands.

    Science.gov (United States)

    Burhans, Dirk E; Thompson, Frank R

    2006-02-01

    Many studies have examined differences in avian community composition between urban and rural habitats, but few, if any, have looked at nesting success of urban shrubland birds in a replicated fashion while controlling for habitat. We tested factors affecting nest survival, parasitism by the Brown-headed Cowbird (Molothrus ater), and species abundance in shrubland habitat in rural and urban landscapes. We found no support for our hypothesis that nest survival was lower in urban landscapes, but strong support for the hypothesis that survival increased with nest height. We found strong support for our hypothesis that cowbird parasitism was greater in urban than rural landscapes; parasitism in urban sites was at least twice that of rural sites. We found strong support for an urban landscape effect on abundance for several species; Northern Cardinal (Cardinalis cardinalis) and Brown-headed Cowbirds were more abundant in urban landscapes, whereas Field Sparrow (Spizella pusilla) and Blue-winged Warbler (Vermivora pinus) were more abundant in rural sites. There was support for lower abundances of Blue-gray Gnatcatcher (Polioptila caerulea) and Indigo Bunting (Passerina cyanea) with increased housing density. For six other species, edge and trail density or vegetation parameters best explained abundance. Lower abundances and greater parasitism in habitat patches in urban landscapes are evidence that, for some species, these urban landscapes do not fulfill the same role as comparable habitats in rural landscapes. Regional bird conservation planning and local habitat management in urban landscapes may need to consider these effects in efforts to sustain bird populations at regional and local scales.

  11. Change in avian abundance predicted from regional forest inventory data

    Science.gov (United States)

    Twedt, Daniel J.; Tirpak, John M.; Jones-Farrand, D. Todd; Thompson, Frank R.; Uihlein, William B.; Fitzgerald, Jane A.

    2010-01-01

    An inability to predict population response to future habitat projections is a shortcoming in bird conservation planning. We sought to predict avian response to projections of future forest conditions that were developed from nationwide forest surveys within the Forest Inventory and Analysis (FIA) program. To accomplish this, we evaluated the historical relationship between silvicolous bird populations and FIA-derived forest conditions within 25 ecoregions that comprise the southeastern United States. We aggregated forest area by forest ownership, forest type, and tree size-class categories in county-based ecoregions for 5 time periods spanning 1963-2008. We assessed the relationship of forest data with contemporaneous indices of abundance for 24 silvicolous bird species that were obtained from Breeding Bird Surveys. Relationships between bird abundance and forest inventory data for 18 species were deemed sufficient as predictive models. We used these empirically derived relationships between regional forest conditions and bird populations to predict relative changes in abundance of these species within ecoregions that are anticipated to coincide with projected changes in forest variables through 2040. Predicted abundances of these 18 species are expected to remain relatively stable in over a quarter (27%) of the ecoregions. However, change in forest area and redistribution of forest types will likely result in changed abundance of some species within many ecosystems. For example, abundances of 11 species, including pine warbler (Dendroica pinus), brown-headed nuthatch (Sitta pusilla), and chuckwills- widow (Caprimulgus carolinensis), are projected to increase within more ecoregions than ecoregions where they will decrease. For 6 other species, such as blue-winged warbler (Vermivora pinus), Carolina wren (Thryothorus ludovicianus), and indigo bunting (Passerina cyanea), we projected abundances will decrease within more ecoregions than ecoregions where they will

  12. On the influence of the environment on galactic chemical abundances

    Science.gov (United States)

    Pilyugin, L. S.; Grebel, E. K.; Zinchenko, I. A.; Nefedyev, Y. A.; Mattsson, L.

    2017-02-01

    We examine the influence of the environment on the chemical abundances of late-type galaxies with masses of 109.1-1011 M⊙ using data from the Sloan Digital Sky Survey. We find that the environmental influence on galactic chemical abundances is strongest for galaxies with masses of 109.1-109.6 M⊙. The galaxies in the densest environments may exceed the average oxygen abundances by about ˜0.05 dex (the median value of the overabundances for 101 galaxies in the densest environments) and show higher abundances in nitrogen by about ˜0.1. The abundance excess decreases with increasing galaxy mass and with decreasing environmental density. Since only a small fraction of late-type galaxies is located in high-density environments, these galaxies do not have a significant influence on the general X/H-M relation. The metallicity-mass relations for isolated galaxies and for galaxies with neighbours are very similar. The mean shift of non-isolated galaxies around the metallicity-mass relation traced by the isolated galaxies is less than ˜0.01 dex for oxygen and less than ˜0.02 dex for nitrogen. The scatter in the galactic chemical abundances is large for any number of neighbour galaxies (at any environmental density), i.e. galaxies with both enhanced and reduced abundances can be found at any environmental density. This suggests that environmental effects do not play a key role in evolution of late-type galaxies, as was also concluded in some of the previous studies.

  13. Microbial abundance in surface ice on the Greenland Ice Sheet

    Directory of Open Access Journals (Sweden)

    Marek eStibal

    2015-03-01

    Full Text Available Measuring microbial abundance in glacier ice and identifying its controls is essential for a better understanding and quantification of biogeochemical processes in glacial ecosystems. However, cell enumeration of glacier ice samples is challenging due to typically low cell numbers and the presence of interfering mineral particles. We quantified for the first time the abundance of microbial cells in surface ice from geographically distinct sites on the Greenland Ice Sheet, using three enumeration methods: epifluorescence microscopy (EFM, flow cytometry (FCM and quantitative polymerase chain reaction (qPCR. In addition, we reviewed published data on microbial abundance in glacier ice and tested the three methods on artificial ice samples of realistic cell (10^2 – 10^7 cells ml-1 and mineral particle (0.1 – 100 mg/ml concentrations, simulating a range of glacial ice types, from clean subsurface ice to surface ice to sediment-laden basal ice. We then used multivariate statistical analysis to identify factors responsible for the variation in microbial abundance on the ice sheet. EFM gave the most accurate and reproducible results of the tested methodologies, and was therefore selected as the most suitable technique for cell enumeration of ice containing dust. Cell numbers in surface ice samples, determined by EFM, ranged from ca 2 x 10^3 to ca 2 x 10^6 cells/ml while dust concentrations ranged from 0.01 to 2 mg/ml. The lowest abundances were found in ice sampled from the accumulation area of the ice sheet and in samples affected by fresh snow; these samples may be considered as a reference point of the cell abundance of precipitants that are deposited on the ice sheet surface. Dust content was the most significant variable to explain the variation in the abundance data, which suggests a direct association between deposited dust particles and cells and/or by their provision of limited nutrients to microbial communities on the Greenland Ice Sheet.

  14. Spatial patterns in the abundance of the coastal horned lizard

    Science.gov (United States)

    Fisher, Robert N.; Suarez, Andrew V.; Case, Ted J.

    2002-01-01

    Coastal horned lizards (   Phrynosoma coronatum) have undergone severe declines in southern California and are a candidate species for state and federal listing under the Endangered Species Act. Quantitative data on their habitat use, abundance, and distribution are lacking, however. We investigated the determinants of abundance for coastal horned lizards at multiple spatial scales throughout southern California. Specifically, we estimated lizard distribution and abundance by establishing 256 pitfall trap arrays clustered within 21 sites across four counties. These arrays were sampled bimonthly for 2–3 years. At each array we measured 26 “local” site descriptors and averaged these values with other “regional” measures to determine site characteristics. Our analyses were successful at identifying factors within and among sites correlated with the presence and abundance of coastal horned lizards. These factors included the absence of the invasive Argentine ant (  Linepithema humile) (and presence of native ant species eaten by the lizards), the presence of chaparral community plants, and the presence of sandy substrates. At a regional scale the relative abundance of Argentine ants was correlated with the relative amount of developed edge around a site. There was no evidence for spatial autocorrelation, even at the scale of the arrays within sites, suggesting that the determinants of the presence or absence and abundance of horned lizard can vary over relatively small spatial scales ( hundreds of meters). Our results suggest that a gap-type approach may miss some of the fine-scale determinants of species abundance in fragmented habitats.

  15. Pulsed plasma arc cladding

    Institute of Scientific and Technical Information of China (English)

    龙; 白钢; 李振民; 张赋升; 杨思乾

    2004-01-01

    A prototype of Pulsed Plasma Arc Cladding system was developed, in which single power source supplies both transferred plasma arc (TPA) and non-transferred plasma arc (N-TPA). Both plasmas work in turn in a high frequency controlled by an IGBT connecting nozzle and workpiece. The working frequency of IGBT ranges from 50 ~ 7000Hz, in which the plasmas can work in turn smoothly. Higher than 500 Hz of working frequency is suggested for promotion of cladding quality and protection of IGBT. Drag phenomenon of TPA intensifies as the frequency goes up, which tends to increase the current proportion of TPA and suppress N-TPA. The occupation ratio of IGBT can be regulated from 5% ~ 95%, which balances the power supplies of both plasmas. An occupation ratio higher than 50% gives adequate proportion of arc current for N-TPA to preheat powder.

  16. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  17. Ultracold Neutral Plasmas

    CERN Document Server

    Killian, T C; Gupta, P; Laha, S; Martinez, Y N; Mickelson, P G; Nagel, S B; Saenz, A D; Simien, C E; Killian, Thomas C.

    2005-01-01

    Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near the ionization threshold. Through the application of atomic physics techniques and diagnostics, these experiments stretch the boundaries of traditional neutral plasma physics. The electron temperature in these plasmas ranges from 1-1000 K and the ion temperature is around 1 K. The density can approach $10^{11}$ cm$^{-3}$. Fundamental interest stems from the possibility of creating strongly-coupled plasmas, but recombination, collective modes, and thermalization in these systems have also been studied. Optical absorption images of a strontium plasma, using the Sr$^+$ ${^2S_{1/2}} -> {^2P_{1/2}}$ transition at 422 nm, depict the density profile of the plasma, and probe kinetics on a 50 ns time-scale. The Doppler-broadened ion absorption spectrum measures the ion velocity distribution, which gives an accurate measure of the ion dynamics in the first microsecond after photoionization.

  18. What is a plasma?

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, Thomas P. [Los Alamos National Laboratory

    2012-08-30

    This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.

  19. Pulsed plasma electron sourcesa)

    Science.gov (United States)

    Krasik, Ya. E.; Yarmolich, D.; Gleizer, J. Z.; Vekselman, V.; Hadas, Y.; Gurovich, V. Tz.; Felsteiner, J.

    2009-05-01

    There is a continuous interest in research of electron sources which can be used for generation of uniform electron beams produced at E ≤105 V/cm and duration ≤10-5 s. In this review, several types of plasma electron sources will be considered, namely, passive (metal ceramic, velvet and carbon fiber with and without CsI coating, and multicapillary and multislot cathodes) and active (ferroelectric and hollow anodes) plasma sources. The operation of passive sources is governed by the formation of flashover plasma whose parameters depend on the amplitude and rise time of the accelerating electric field. In the case of ferroelectric and hollow-anode plasma sources the plasma parameters are controlled by the driving pulse and discharge current, respectively. Using different time- and space-resolved electrical, optical, spectroscopical, Thomson scattering and x-ray diagnostics, the parameters of the plasma and generated electron beam were characterized.

  20. Age-related differences in plasma proteins: how plasma proteins change from neonates to adults.

    Directory of Open Access Journals (Sweden)

    Vera Ignjatovic

    Full Text Available The incidence of major diseases such as cardiovascular disease, thrombosis and cancer increases with age and is the major cause of mortality world-wide, with neonates and children somehow protected from such diseases of ageing. We hypothesized that there are major developmental differences in plasma proteins and that these contribute to age-related changes in the incidence of major diseases. We evaluated the human plasma proteome in healthy neonates, children and adults using the 2D-DIGE approach. We demonstrate significant changes in number and abundance of up to 100 protein spots that have marked differences in during the transition of the plasma proteome from neonate and child through to adult. These proteins are known to be involved in numerous physiological processes such as iron transport and homeostasis, immune response, haemostasis and apoptosis, amongst others. Importantly, we determined that the proteins that are differentially expressed with age are not the same proteins that are differentially expressed with gender and that the degree of phosphorylation of plasma proteins also changes with age. Given the multi-functionality of these proteins in human physiology, understanding the differences in the plasma proteome in neonates and children compared to adults will make a major contribution to our understanding of developmental biology in humans.

  1. A Retrospectively Diagnosed Case of IgG4-Related Tubulointerstitial Nephritis Showing Good Renal Outcome and Pathological Progress

    Directory of Open Access Journals (Sweden)

    Qiong Wu

    2013-01-01

    Full Text Available A 74-year-old man was hospitalized for diabetic nephropathy evaluation and assessment of the effect of treatment on his tubulointerstitial nephritis (TIN. When he was 62 years old, he developed polyarthralgia and had superficial lymph node swelling, mildly increased serum creatinine concentration, hypergammaglobulinemia, hypocomplementemia, high serum IL-2R level, and positive titer of antinuclear antibody. Several tissues were biopsied. Mild chronic sialadenitis and reactive lymphadenitis were identified. Renal specimen showed mild glomerular ischemia, extensive storiform fibrosis, and abundant infiltrating monocytes and plasma cells. He was treated with oral prednisolone and cyclophosphamide. After the treatment, most of his clinical parameters quickly returned to within the reference range. However, he developed diabetes mellitus soon after steroid therapy. At the time of rebiopsy, a high level of serum IgG4 was detected. The second renal biopsy showed diabetic nephropathy without any tubulointerstitial damage. The first biopsied tissues were retrospectively investigated. Large numbers of IgG4-positive plasma cells were detected in the kidneys and lymph nodes. A retrospective diagnosis of IgG4-related TIN with lymph node involvement was made. In conclusion, this paper describes a retrospectively diagnosed case of IgG4-related TIN with lymph node involvement, showing good clinical and pathological prognosis.

  2. Space plasma physics research

    Science.gov (United States)

    Comfort, Richard H.; Horwitz, James L.

    1993-01-01

    During the course of this grant, work was performed on a variety of topics and there were a number of significant accomplishments. A summary of these accomplishments is included. The topics studied include empirical model data base, data reduction for archiving, semikinetic modeling of low energy plasma in the inner terrestrial magnetosphere and ionosphere, O(+) outflows, equatorial plasma trough, and plasma wave ray-tracing studies. A list of publications and presentations which have resulted from this research is also included.

  3. Atmospheric Plasma Depainting

    Science.gov (United States)

    2014-11-19

    Plasma Carbon Dioxide Water Vapor 11 Atmospheric Plasma Depainting, ASETSDefense, Nov 19, 2014 Features and Benefits of APCR Technology Feature...Depainting, ASETSDefense, Nov 19, 2014 14 APC on Aluminum Removal to Primer RAM on Carbon Fiber Partial Topcoat Removal APC Topcoat RAM...60Hz Plasma Flux™ Power Supply VENT To Facility HEPA <= Filtration COTS Six-Axis Robot Aircraft part Particulate Collection System

  4. Plasma nitriding of steels

    CERN Document Server

    Aghajani, Hossein

    2017-01-01

    This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .

  5. New aerial survey and hierarchical model to estimate manatee abundance

    Science.gov (United States)

    Langimm, Cahterine A.; Dorazio, Robert M.; Stith, Bradley M.; Doyle, Terry J.

    2011-01-01

    Monitoring the response of endangered and protected species to hydrological restoration is a major component of the adaptive management framework of the Comprehensive Everglades Restoration Plan. The endangered Florida manatee (Trichechus manatus latirostris) lives at the marine-freshwater interface in southwest Florida and is likely to be affected by hydrologic restoration. To provide managers with prerestoration information on distribution and abundance for postrestoration comparison, we developed and implemented a new aerial survey design and hierarchical statistical model to estimate and map abundance of manatees as a function of patch-specific habitat characteristics, indicative of manatee requirements for offshore forage (seagrass), inland fresh drinking water, and warm-water winter refuge. We estimated the number of groups of manatees from dual-observer counts and estimated the number of individuals within groups by removal sampling. Our model is unique in that we jointly analyzed group and individual counts using assumptions that allow probabilities of group detection to depend on group size. Ours is the first analysis of manatee aerial surveys to model spatial and temporal abundance of manatees in association with habitat type while accounting for imperfect detection. We conducted the study in the Ten Thousand Islands area of southwestern Florida, USA, which was expected to be affected by the Picayune Strand Restoration Project to restore hydrology altered for a failed real-estate development. We conducted 11 surveys in 2006, spanning the cold, dry season and warm, wet season. To examine short-term and seasonal changes in distribution we flew paired surveys 1–2 days apart within a given month during the year. Manatees were sparsely distributed across the landscape in small groups. Probability of detection of a group increased with group size; the magnitude of the relationship between group size and detection probability varied among surveys. Probability

  6. Plasma adiabatic lapse rate

    CERN Document Server

    Amendt, Peter; Wilks, Scott

    2012-01-01

    The plasma analog of an adiabatic lapse rate (or temperature variation with height) in atmospheric physics is obtained. A new source of plasma temperature gradient in a binary ion species mixture is found that is proportional to the concentration gradient and difference in average ionization states . Application to inertial-confinement-fusion implosions indicates a potentially strong effect in plastic (CH) ablators that is not modeled with mainline (single-fluid) simulations. An associated plasma thermodiffusion coefficient is derived, and charge-state diffusion in a single-species plasma is also predicted.

  7. Nonlinear Physics of Plasmas

    CERN Document Server

    Kono, Mitsuo

    2010-01-01

    A nonlinearity is one of the most important notions in modern physics. A plasma is rich in nonlinearities and provides a variety of behaviors inherent to instabilities, coherent wave structures and turbulence. The book covers the basic concepts and mathematical methods, necessary to comprehend nonlinear problems widely encountered in contemporary plasmas, but also in other fields of physics and current research on self-organized structures and magnetized plasma turbulence. The analyses make use of strongly nonlinear models solved by analytical techniques backed by extensive simulations and available experiments. The text is written for senior undergraduates, graduate students, lecturers and researchers in laboratory, space and fusion plasmas.

  8. Physics of Plasmas

    CERN Document Server

    Woods, Leslie Colin

    2003-01-01

    A short, self-sufficient introduction to the physics of plasma for beginners as well as researchers in a number of fields. The author looks at the dynamics and stability of magnetoplasma and discusses wave and transport in this medium. He also looks at such applications as fusion research using magnetic confinement of Deuterium plasma, solar physics with its plasma loops reaching high into the corona, sunspots and solar wind, engineering applications to metallurgy, MHD direct generation of electricity, and railguns, finally touching on the relatively new and difficult subject of dusty plasmas.

  9. Princeton Plasma Physics Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  10. Solid expellant plasma generator

    Science.gov (United States)

    Stone, Nobie H. (Inventor); Poe, Garrett D. (Inventor); Rood, Robert (Inventor)

    2010-01-01

    An improved solid expellant plasma generator has been developed. The plasma generator includes a support housing, an electrode rod located in the central portion of the housing, and a mass of solid expellant material that surrounds the electrode rod within the support housing. The electrode rod and the solid expellant material are made of separate materials that are selected so that the electrode and the solid expellant material decompose at the same rate when the plasma generator is ignited. This maintains a point of discharge of the plasma at the interface between the electrode and the solid expellant material.

  11. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G

    1984-01-01

    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  12. Plasma and particles

    Science.gov (United States)

    Špatenka, Petr; Vacková, Tat'ana; Nováček, Vojtěch; Jeníková, Zdenka

    2016-12-01

    Plasma has been proved as a standard industrial method for surface treatment of solid bulk materials. Recently plasma has also been used in connection with production, treatment and functionalization of powder and granulate materials. Functionalization was originally developed for hydrophylization of hydrophobic surfaces of particles made from various materials. An industrial scale device with a capacity of several hundreds of tons per year based on plasma treatment will be presented. As examples of the applications are given plasma treated polyethylene powder dispersed in the water; and very good adhesion of polymer powders to metals or glass, which is promising for development of new generation of thermoplastic composites.

  13. Pharmacological zinc and phytase supplementation enhance metallothionein mRNA abundance and protein concentration in newly weaned pigs.

    Science.gov (United States)

    Martínez, Michelle M; Hill, Gretchen M; Link, Jane E; Raney, Nancy E; Tempelman, Robert J; Ernst, Catherine W

    2004-03-01

    The swine industry feeds pharmacological zinc (Zn) to newly weaned pigs to improve health. Because most swine diets are plant-based with a high phytic acid content, we hypothesized that adding phytase to diets could reduce the amount of Zn required to obtain beneficial responses. The role of metallothionein (MT) in Zn homeostasis could be important in this positive response. Thus, the goal of this study was to investigate the effect of dietary Zn and phytase on relative MT mRNA abundance and protein concentration in newly weaned pigs. Diets containing adequate (150 mg Zn/kg) or pharmacological concentrations of Zn (1000 or 2000 mg Zn/kg), as zinc oxide, with or without phytase [0, 500 phytase units (FTU)/kg, Natuphos, BASF] were fed in a 3 x 2 factorial design. Plasma and tissue minerals were measured in pigs killed after 14 d of dietary intervention. Hepatic and renal relative MT mRNA abundance and protein were greater (P pigs fed 1000 mg Zn/kg with phytase, or 2000 mg Zn/kg with or without phytase vs. the remaining treatments. Intestinal mucosa MT mRNA abundance and protein were greater (P pigs fed 2000 mg Zn/kg with phytase than in pigs fed 2000 mg Zn/kg alone or 1000 mg Zn/kg with phytase. Pigs fed 1000 mg Zn/kg plus phytase or 2000 mg Zn/kg with or without phytase had higher plasma, hepatic, and renal Zn than those fed the adequate Zn diets or 1000 mg Zn/kg. We conclude that feeding 1000 mg Zn/kg with phytase enhances MT mRNA abundance and protein and Zn absorption to the same degree as 2000 mg Zn/kg with and without phytase.

  14. Factors affecting Culicoides species composition and abundance in avian nests.

    Science.gov (United States)

    Martínez-de la Puente, J; Merino, S; Tomás, G; Moreno, J; Morales, J; Lobato, E; Talavera, S; Sarto I Monteys, V

    2009-08-01

    Mechanisms affecting patterns of vector distribution among host individuals may influence the population and evolutionary dynamics of vectors, hosts and the parasites transmitted. We studied the role of different factors affecting the species composition and abundance of Culicoides found in nests of the blue tit (Cyanistes caeruleus). We identified 1531 females and 2 males of 7 different Culicoides species in nests, with C. simulator being the most abundant species, followed by C. kibunensis, C. festivipennis, C. segnis, C. truncorum, C. pictipennis and C. circumscriptus. We conducted a medicationxfumigation experiment randomly assigning bird's nests to different treatments, thereby generating groups of medicated and control pairs breeding in fumigated and control nests. Medicated pairs were injected with the anti-malarial drug Primaquine diluted in saline solution while control pairs were injected with saline solution. The fumigation treatment was carried out using insecticide solution or water for fumigated and control nests respectively. Brood size was the main factor associated with the abundance of biting midges probably because more nestlings may produce higher quantities of vector attractants. In addition, birds medicated against haemoparasites breeding in non-fumigated nests supported a higher abundance of C. festivipennis than the rest of the groups. Also, we found that the fumigation treatment reduced the abundance of engorged Culicoides in both medicated and control nests, thus indicating a reduction of feeding success produced by the insecticide. These results represent the first evidence for the role of different factors in affecting the Culicoides infracommunity in wild avian nests.

  15. New Radial Abundance Gradients for NGC 628 and NGC 2403

    CERN Document Server

    Berg, Danielle A; Garnett, Donald R; Croxall, Kevin V; Marble, Andrew R; Smith, J D; Gordon, Karl; Kennicutt, Robert C

    2013-01-01

    Motived by recent ISM studies, we present high quality MMT and Gemini spectroscopic observations of H II regions in the nearby spiral galaxies NGC 628 and NGC 2403 in order to measure their chemical abundance gradients. Using long-slit and multi-object mask optical spectroscopy, we obtained measurements of the temperature sensitive auroral lines [O III] {\\lambda}4363 and/or [N II] {\\lambda}5755 at a strength of 4{\\sigma} or greater in 11 H II regions in NGC 628 and 7 regions in NGC 2403. These observations allow us, for the first time, to derive an oxygen abundance gradient in NGC 628 based solely on "direct" oxygen abundances of H II regions: 12 + log(O/H) = (8.43+/-0.03) + (-0.017+/-0.002) x Rg (dex/kpc), with a dispersion in log(O/H) of {\\sigma} = 0.10 dex, from 14 regions with a radial coverage of ~2-19 kpc. This is a significantly shallower slope than found by previous "strong-line" abundance studies. In NGC 2403, we derive an oxygen abundance gradient of 12 + log(O/H) = (8.48+/-0.04) + (-0.032+/-0.007) ...

  16. Enhanced Abundances in Spiral Galaxies of the Pegasus I Cluster

    CERN Document Server

    Robertson, Paul; Blanc, Guillermo A

    2011-01-01

    We study the influence of cluster environment on the chemical evolution of spiral galaxies in the Pegasus I cluster. We determine the gas-phase heavy element abundances of six galaxies in Pegasus derived from H II region spectra obtained from integral-field spectroscopy. These abundances are analyzed in the context of Virgo, whose spirals are known to show increasing interstellar metallicity as a function of H I deficiency. The galaxies in the Pegasus cluster, despite its lower density and velocity dispersion, also display gas loss due to ISM-ICM interaction, albeit to a lesser degree. Based on the abundances of 3 H I deficient spirals and 2 H I normal spirals, we observe a heavy element abundance offset of +0.13\\pm0.07 dex for the H I deficient galaxies. This abundance differential is consistent with the differential observed in Virgo for galaxies with a similar H I deficiency, and we observe a correlation between log(O/H) and the H I deficiency parameter DEF for the two clusters analyzed together. Our resul...

  17. Sulfur and zinc abundances of red giant stars

    CERN Document Server

    Takeda, Yoichi; Harakawa, Hiroki; Sato, Bun'ei

    2016-01-01

    Sulfur and zinc are chemically volatile elements, which play significant roles as depletion-free tracers in studying galactic chemical evolution. However, regarding red giants having evolved off the main sequence, reliable abundance determinations of S and Zn seem to be difficult despite that a few studies have been reported so far. Given this situation, we tried to establish the abundances of these elements for an extensive sample of 239 field GK giants (-0.8 < [Fe/H] < +0.2), by applying the spectrum-fitting technique to S I 8694-5, S I 6757, and Zn I 6362 lines and by taking into account the non-LTE effect. Besides, similar abundance analysis was done for 160 FGK dwarfs to be used for comparison. The non-LTE corrections for the S and Zn abundances derived from these lines turned out < 0.1(-0.2) dex for most cases and not very significant. It revealed that the S I 6757 feature is more reliable as an abundance indicator than S I 8694-5 for the case of red giants, because the latter suffers blending ...

  18. Abundances and diffusion of elements in M67 stars

    CERN Document Server

    Önehag, Anna; Korn, Andreas

    2013-01-01

    We present a spectroscopic study at high resolution, R~50,000, of 14 stars located on the main sequence, at the turn-off point and on the early subgiant branch in the cluster M67 in order to investigate its detailed chemical composition, for comparison with the Sun and solar twins in the solar neighbourhood, and to explore selective atomic diffusion of chemical elements as predicted by stellar-structure theory. We have obtained VLT/FLAMES-UVES spectra and analysed these strictly differentially in order to explore chemical-abundance similarities and differences between the M67 stars and the Sun, and among the M67 stars themselves. Individual abundances of 19 different chemical elements are obtained for the stars. They are found to agree very well with solar abundances, with abundance ratios closer to solar than those of most solar twins in the solar neighbourhood. An exception is Li which shows a considerable scatter among the cluster stars. There is a tendency for the cluster-star abundances to be depleted re...

  19. Carbon and Oxygen abundances across the Hertzsprung gap

    CERN Document Server

    Adamczak, Jens

    2014-01-01

    We derived atmospheric parameters and spectroscopic abundances for C and O for a large sample of stars located in the Hertzsprung gap in the Hertzsprung-Russell Diagram in order to detect chemical peculiarities and get a comprehensive overview of the population of stars in this evolutionary state. We have observed and analyzed high resolution spectra (R = 60 000) of 188 stars in the mass range 2 - 5 Msun with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory including 28 stars previously identified as Am/Ap stars. We find that the C and O abundances of the majority of stars in the Hertzsprung gap are in accordance with abundances derived for local lower mass dwarfs but detect expected peculiarities for the Am/Ap stars. The C and O abundances of stars with Teff < 6500 K are slightly lower than for the hotter objects but the C/O ratio is constant in the analyzed temperature domain. No indication of an alteration of the C and O abundances of the stars by mixing during the evolution across the He...

  20. Origin and abundance of beach debris in the Balearic Islands

    Directory of Open Access Journals (Sweden)

    Lorena Martinez-Ribes

    2007-06-01

    Full Text Available The abundance, nature and possible sources of litter on 32 beaches on the Balearic Islands (Mediterranean Sea were investigated in 2005. Mean summer abundances in the Balearics reached approximately 36 items m-1, with a corresponding weight of 32±25 g m-1, which is comparable to the results of other studies in the Mediterranean. Multivariate analyses (principal component analysis and redundancy analysis confirmed strong similarities between islands and a statistically significant seasonal evolution of litter composition and abundance. In summer (the high tourist season, debris contamination expressed as item abundance was double that in the low season and showed a heterogeneous nature associated with beach use. Cigarette butts were the most abundant item, accounting for up to 46% of the objects observed in the high tourist season. In contrast, plastics related to personal hygiene/medical items were predominant in wintertime (67% and natural wood was the most important debris by weight (75%. In both seasons, litter characteristics suggested a strong relationship with local land-based origins. While beach users were the main source of summer debris, low tourist season litter was primarily attributed to drainage and outfall systems.

  1. Chemical abundances of stars with brown-dwarf companions

    CERN Document Server

    Sánchez, D Mata; Israelian, G; Santos, N C; Sahlmann, J; Udry, S

    2014-01-01

    It is well-known that stars with giant planets are on average more metal-rich than stars without giant planets, whereas stars with detected low-mass planets do not need to be metal-rich. With the aim of studying the weak boundary that separates giant planets and brown dwarfs (BDs) and their formation mechanism, we analyze the spectra of a sample of stars with already confirmed BD companions both by radial velocity and astrometry. We employ standard and automatic tools to perform an EW-based analysis and to derive chemical abundances from CORALIE spectra of stars with BD companions. We compare these abundances with those of stars without detected planets and with low-mass and giant-mass planets. We find that stars with BDs do not have metallicities and chemical abundances similar to those of giant-planet hosts but they resemble the composition of stars with low-mass planets. The distribution of mean abundances of $\\alpha$-elements and iron peak elements of stars with BDs exhibit a peak at about solar abundance...

  2. Lithium isotopic abundances in metal-poor halo stars

    CERN Document Server

    Asplund, M; Nissen, P E; Primas, F; Smith, V V; Asplund, Martin; Lambert, David L.; Nissen, Poul Erik; Primas, Francesca; Smith, Verne V.

    2005-01-01

    Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from the LiI 670.8nm line reveal a pronounced dependence on metallicity but with negligible scatter around this trend. Very good agreement is found between the abundances from the LiI 670.8nm line and the LiI 610.4nm line. The estimated primordial 7Li abundance is $7Li/H = 1.1-1.5 x 10^-10, which is a factor of three to four lower than predicted from standard Big Bang nucleosynthesis with the baryon density inferred from the cosmic microwave background. Interestingly, 6Li is detected in nine of our 24 stars at the >2sigma significance level. Our observations suggest the existence of a 6Li plateau at the level of log 6Li = 0.8; however, taking into account predictions for 6Li destruction during the pre-main sequence evolution tilts the plateau such that the 6Li abundances apparently increase with metallicity. Ou...

  3. Spectroscopic Study on the Beryllium Abundances of Red Giant Stars

    CERN Document Server

    Takeda, Yoichi

    2014-01-01

    An extensive spectroscopic study was carried out for the beryllium abundances of 200 red giants (mostly of late G and early K type), which were determined from the near-UV Be II 3131.066 line based on high-dispersion spectra obtained by Subaru/HDS, with an aim of investigating the nature of surface Be contents in these evolved giants; e.g., dependence upon stellar parameters, degree of peculiarity along with its origin and build-up timing. We found that Be is considerably deficient (to widely different degree from star to star) in the photosphere of these evolved giants by ~1-3 dex (or more) compared to the initial abundance. While the resulting Be abundances (A(Be)) appear to weakly depend upon T_eff, log g, [Fe/H], M, age, and v_sin i, this may be attributed to the metallicity dependence of A(Be) coupled with the mutual correlation between these stellar parameters, since such tendencies almost disappear in the metallicity-scaled Be abundance ([Be/Fe]). By comparing the Be abundances (as well as their correl...

  4. Generalized estimators of avian abundance from count survey data

    Directory of Open Access Journals (Sweden)

    Royle, J. A.

    2004-01-01

    Full Text Available I consider modeling avian abundance from spatially referenced bird count data collected according to common protocols such as capture-recapture, multiple observer, removal sampling and simple point counts. Small sample sizes and large numbers of parameters have motivated many analyses that disregard the spatial indexing of the data, and thus do not provide an adequate treatment of spatial structure. I describe a general framework for modeling spatially replicated data that regards local abundance as a random process, motivated by the view that the set of spatially referenced local populations (at the sample locations constitute a metapopulation. Under this view, attention can be focused on developing a model for the variation in local abundance independent of the sampling protocol being considered. The metapopulation model structure, when combined with the data generating model, define a simple hierarchical model that can be analyzed using conventional methods. The proposed modeling framework is completely general in the sense that broad classes of metapopulation models may be considered, site level covariates on detection and abundance may be considered, and estimates of abundance and related quantities may be obtained for sample locations, groups of locations, unsampled locations. Two brief examples are given, the first involving simple point counts, and the second based on temporary removal counts. Extension of these models to open systems is briefly discussed.

  5. On the influence of the environment on galactic chemical abundances

    CERN Document Server

    Pilyugin, L S; Zinchenko, I A; Nefedyev, Y A; Mattsson, L

    2016-01-01

    We examine the influence of the environment on the chemical abundances of late-type galaxies with masses of 10^9.1 M_sun - 10^11 M_sun using data from the Sloan Digital Sky Survey(SDSS). We find that the environmental influence on galactic chemical abundances is strongest for galaxies with masses of 10^9.1 M_sun to 10^9.6 Msun. The galaxies in the densest environments may exceed the average oxygen abundances by about 0.05 dex (the median value of the overabundances for 101 galaxies in the densest environments) and show higher abundances in nitrogen by about 0.1. The abundance excess decreases with increasing galaxy mass and with decreasing environmental density. Since only a small fraction of late-type galaxies is located in high-density environments these galaxies do not have a significant influence on the general X/H - M relation. The metallicity - mass relations for isolated galaxies and for galaxies with neighbors are very similar. The mean shift of non-isolated galaxies around the metallicity - mass rela...

  6. Study on the Abundance Discrepancy Problem in the Magellanic Clouds

    CERN Document Server

    Cipriano, L Toribio San; Domínguez-Guzmán, G; García-Rojas, J

    2016-01-01

    We present chemical abundances of carbon (C) and oxygen (O) in the Large and Small Magellanic Clouds from deep and high-quality optical spectra of HII regions. The data have been taken using the Ultraviolet-Visual Echelle Spectrograph at the 8.2-m Very Large Telescope with the goal of detecting the faint CII and OII recombination lines. For all the objects of the sample, we determine C^2+ abundances from recombination lines and O^2+ abundances from recombination lines and collisionally excited lines. In addition, we calculate the abundance discrepancy factors (ADFs) for O^2+ and C^2+, as well as the O/H, C/H and C/O ratios. We study the behaviour of the ADF comparing the values obtained in the Magellanic Clouds with those obtained for other HII regions in different galaxies. We also compare the nebular and stellar abundances in two regions of the sample. Finally, we discuss the chemical evolution of the MCs through the O/H, C/H and C/O radial gradients and the changes of the C/O ratio as a function of O/H.

  7. Analysis and modeling of scale-invariance in plankton abundance

    CERN Document Server

    Pelletier, J D

    1996-01-01

    The power spectrum, $S$, of horizontal transects of plankton abundance are often observed to have a power-law dependence on wavenumber, $k$, with exponent close to $-2$: $S(k)\\propto k^{-2}$ over a wide range of scales. I present power spectral analyses of aircraft lidar measurements of phytoplankton abundance from scales of 1 to 100 km. A power spectrum $S(k)\\propto k^{-2}$ is obtained. As a model for this observation, I consider a stochastic growth equation where the rate of change of plankton abundance is determined by turbulent mixing, modeled as a diffusion process in two dimensions, and exponential growth with a stochastically variable net growth rate representing a fluctuating environment. The model predicts a lognormal distribution of abundance and a power spectrum of horizontal transects $S(k)\\propto k^{-1.8}$, close to the observed spectrum. The model equation predicts that the power spectrum of variations in abundance in time at a point in space is $S(f)\\propto f^{-1.5}$ (where $f$ is the frequency...

  8. Stellar chemical abundances: in pursuit of the highest achievable precision

    Energy Technology Data Exchange (ETDEWEB)

    Bedell, Megan; Bean, Jacob L. [Department of Astronomy and Astrophysics, University of Chicago, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Meléndez, Jorge; Leite, Paulo [Departamento de Astronomia do IAG/USP, Universidade de São Paulo, Rua do Matão 1226, Cidade Universitária, São Paulo, SP 05508-900 (Brazil); Ramírez, Ivan [McDonald Observatory and Department of Astronomy, University of Texas at Austin, Austin, TX 78712-1206 (United States); Asplund, Martin, E-mail: mbedell@oddjob.uchicago.edu [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT 2611 (Australia)

    2014-11-01

    The achievable level of precision on photospheric abundances of stars is a major limiting factor on investigations of exoplanet host star characteristics, the chemical histories of star clusters, and the evolution of the Milky Way and other galaxies. While model-induced errors can be minimized through the differential analysis of spectrally similar stars, the maximum achievable precision of this technique has been debated. As a test, we derive differential abundances of 19 elements from high-quality asteroid-reflected solar spectra taken using a variety of instruments and conditions. We treat the solar spectra as being from unknown stars and use the resulting differential abundances, which are expected to be zero, as a diagnostic of the error in our measurements. Our results indicate that the relative resolution of the target and reference spectra is a major consideration, with use of different instruments to obtain the two spectra leading to errors up to 0.04 dex. Use of the same instrument at different epochs for the two spectra has a much smaller effect (∼0.007 dex). The asteroid used to obtain the solar standard also has a negligible effect (∼0.006 dex). Assuming that systematic errors from the stellar model atmospheres have been minimized, as in the case of solar twins, we confirm that differential chemical abundances can be obtained at sub-0.01 dex precision with due care in the observations, data reduction, and abundance analysis.

  9. Detailed photospheric abundances of 28 Peg and HD 202240

    CERN Document Server

    Elmasli, Asli; Kilicoglu, Tolgahan; Unal, Kubraozge; Nasolo, Yahya; Albayrak, Berahitdin

    2015-01-01

    The atmospheric parameters and chemical abundances of two neglected A-type stars, 28 Peg and HD 202240, were derived using high resolution spectra obtained at the TUBITAK National Observatory. We determined the photospheric abundances of eleven elements for 28 Peg and twenty for HD 202240, using equivalent-width measurement and spectral synthesis methods. Their abundance patterns are in good agreement with those of chemically normal A-type stars having similar atmospheric parameters. We pinpoint the position of these stars on the H-R diagram and estimate their masses and ages as; $2.60\\pm0.10\\ M_\\odot$ and $650\\pm50\\ Myr$ for 28 Peg and $4.50\\pm0.09\\ M_\\odot$ and $150\\pm10\\ Myr$ for HD 202240. To compare our abundance determinations with those of stars having similar ages and atmospheric parameters, we select members of open clusters. We notice that our target stars exhibit similar abundance patterns with these members.

  10. Zooplankton abundance in subtropical waters: is there a lunar cycle?

    Directory of Open Access Journals (Sweden)

    Santiago Hernández-León

    2001-07-01

    Full Text Available Based on historical data of abundance, we report evidence of changes in zooplankton abundance in the 0-200 m layer related to the moon cycle confirming that this phenomenon is produced in the marine environment, similarly to the one described for freshwater ecosystems. A clear decrease in the abundance of copepodites plus copepods was observed from the second to the fourth quarter of the moon when the seasonal variability was suppressed. During the full moon phase the large zooplankton and micronekton of the deep scattering layers (DSL would not reach the upper mixed layer in order to avoid predation because of the relatively high level of illumination. Thus epipelagic zooplankton abundance increases as the effect of a lower predatory pressure. Conversely, during the new moon phase the diel migrants reach the surface waters and epiplankton abundance considerably decreases. Recent oceanic sediment trap data in subtropical waters indicate that the particle flux increases at about 30 days period. Thus, the effect of diel vertical migrants could promote not only the variability in their resources and the intensity of the active flux, but could also drive the variability in the gravitational flux.

  11. Dispersal ability determines the scaling properties of species abundance distributions

    DEFF Research Database (Denmark)

    Borda-De-Água, Luís; Whittaker, Robert James; Cardoso, Pedro

    2017-01-01

    Species abundance distributions (SAD) are central to the description of diversity and have played a major role in the development of theories of biodiversity and biogeography. However, most work on species abundance distributions has focused on one single spatial scale. Here we used data on arthr......Species abundance distributions (SAD) are central to the description of diversity and have played a major role in the development of theories of biodiversity and biogeography. However, most work on species abundance distributions has focused on one single spatial scale. Here we used data...... on arthropods to test predictions obtained with computer simulations on whether dispersal ability influences the rate of change of SADs as a function of sample size. To characterize the change of the shape of the SADs we use the moments of the distributions: the skewness and the raw moments. In agreement...... with computer simulations, low dispersal ability species generate a hump for intermediate abundance classes earlier than the distributions of high dispersal ability species. Importantly, when plotted as function of sample size, the raw moments of the SADs of arthropods have a power law pattern similar...

  12. Correlation between lithium abundances and ages of solar twin stars

    CERN Document Server

    Carlos, Marilia; Melendez, Jorge

    2016-01-01

    We want to determine the lithium abundances of solar twin stars as a function of stellar age to provide constraints for stellar evolutions models and to investigate whether there is a connection between low Li abundance and the occurrence of planets. For a sample of 21 solar twins observed with the HARPS spectrograph at high spectral resolution (R~115.000) and very high signal-to-noise ratio (600 < S/N < 2400), precise lithium abundances were obtained by spectral synthesis of the LiI 6707.8 A line and compared to stellar ages, masses, and metallicities determined from a spectroscopic analysis of the same set of HARPS spectra. We show that for the large majority of the solar twins there is a strong correlation between lithium abundance and stellar age. As the age increases from 1 to 9 Gyr, the Li abundance decreases by a factor of ~ 50. The relation agrees fairly well with predictions from non-standard stellar evolution models of Li destruction at the bottom of the upper convection zone. Two stars deviat...

  13. Neutron-Capture Element Abundances in Magellanic Cloud Planetary Nebulae

    CERN Document Server

    Mashburn, A L; Madonna, S; Dinerstein, H L; Roederer, I U; Geballe, T

    2016-01-01

    We present near-infrared spectra of ten planetary nebulae (PNe) in the Large and Small Magellanic Clouds (LMC and SMC), acquired with the FIRE and GNIRS spectrometers on the 6.5-m Baade and 8.1-m Gemini South Telescopes, respectively. We detect Se and/or Kr emission lines in eight of these objects, the first detections of n-capture elements in Magellanic Cloud PNe. Our abundance analysis shows large s-process enrichments of Kr (0.6-1.3 dex) in the six PNe in which it was detected, and Se is enriched by 0.5-0.9 dex in five objects. We also estimate upper limits to Rb and Cd abundances in these objects. Our abundance results for the LMC are consistent with the hypothesis that PNe with 2--3 M$_{\\odot}$ progenitors dominate the bright end of the PN luminosity function in young gas-rich galaxies. We find no significant correlations between s-process enrichments and other elemental abundances, central star temperature, or progenitor mass, though this is likely due to our small sample size. We determine S abundances...

  14. Generation of metal ions in the beam plasma produced by a forevacuum-pressure electron beam source

    Energy Technology Data Exchange (ETDEWEB)

    Tyunkov, A. V.; Yushkov, Yu. G., E-mail: YuYushkov@sibmail.com; Zolotukhin, D. B.; Klimov, A. S. [Tomsk State University of Control Systems and Radioelectronics, Tomsk 634050 (Russian Federation); Savkin, K. P. [High Current Electronics Institute, Russian Academy of Sciences, Tomsk 634055 (Russian Federation)

    2014-12-15

    We report on the production of metal ions of magnesium and zinc in the beam plasma formed by a forevacuum-pressure electron source. Magnesium and zinc vapor were generated by electron beam evaporation from a crucible and subsequently ionized by electron impact from the e-beam itself. Both gaseous and metallic plasmas were separately produced and characterized using a modified RGA-100 quadrupole mass-spectrometer. The fractional composition of metal isotopes in the plasma corresponds to their fractional natural abundance.

  15. Hitomi results on the Perseus cluster thermodynamics, elemental abundances, and emission processes

    Science.gov (United States)

    Markevitch, Maxim L.; Hitomi Collaboration

    2017-01-01

    Hitomi SXS spectrum of the Perseus cluster above E=2 keV is a treasure trove of emission lines, most of them seen for the first time from a diffuse source such as the plasma atmosphere of a galaxy cluster. Several trace elements are detected for the first time in the intracluster medium, lines from several key elements, such as S/Ar and Fe/Ni, are disentangled, and sensitivity to faint lines is dramatically higher compared to previous, lower-resolution cluster studies. This allows us to determine accurate relative abundances of heavy elements, a sensitive test for sources of enrichment of the intergalactic medium. For many elements, lines from multiple ions are observed, as well as multiple transitions from the same ion, providing plasma temperature diagnostics previously unavailable for clusters. The brightest line -- the resonant component of the Fe He-alpha triplet -- is found to be affected by resonant scattering. For the most prominent ions, very high-level transitions are observed, placing constraints on such emission mechanisms as charge exchange with cold gas. Finally, we do not observe a previously reported 3.5 keV emission line from the Perseus core and place an upper limit on it.

  16. An MCMC determination of the primordial helium abundance

    CERN Document Server

    Aver, Erik; Skillman, Evan D

    2011-01-01

    Spectroscopic observations of the chemical abundances in metal-poor H II regions provide an independent method for estimating the primordial helium abundance. H II regions are described by several physical parameters such as electron density, electron temperature, and reddening, in addition to y, the ratio of helium to hydrogen. It had been customary to estimate or determine self-consistently these parameters to calculate y. Frequentist analyses of the parameter space have been shown to be successful in these determinations, and Markov Chain Monte Carlo (MCMC) techniques have proven to be very efficient in sampling this parameter space. Nevertheless, accurate determination of the primordial helium abundance from observations of H II regions is constrained by both systematic and statistical uncertainties. In an attempt to better reduce the latter, and better characterize the former, we apply MCMC methods to the large dataset recently compiled by Izotov, Thuan, & Stasinska (2007). To improve the reliability...

  17. The effects of He I 10830 on helium abundance determinations

    CERN Document Server

    Aver, Erik; Skillman, Evan D

    2015-01-01

    Observations of helium and hydrogen emission lines from metal-poor extragalactic H II regions provide an independent method for determining the primordial helium abundance, Y_p. Traditionally, the emission lines employed are in the visible wavelength range, and the number of suitable lines is limited. Furthermore, when using these lines, large systematic uncertainties in helium abundance determinations arise due to the degeneracy of physical parameters, such as temperature and density. Recently, Izotov, Thuan, & Guseva (2014) have pioneered adding the He 10830 infrared emission line in helium abundance determinations. The strong electron density dependence of He 10830 makes it ideal for better constraining density, potentially breaking the degeneracy with temperature. We revisit our analysis of the dataset published by Izotov, Thuan, & Stasinska (2007) and incorporate the newly available observations of He 10830 by scaling them using the observed-to-theoretical Paschen-gamma ratio. The solutions are b...

  18. Relative species abundance of replicator dynamics with sparse interactions

    CERN Document Server

    Obuchi, Tomoyuki; Tokita, Kei

    2016-01-01

    A theory of relative species abundance on sparsely-connected networks is presented by investigating the replicator dynamics with symmetric interactions. Sparseness of a network involves difficulty in analyzing the fixed points of the equation, and we avoid this problem by treating large self interaction $u$, which allows us to construct a perturbative expansion. Based on this perturbation, we find that the nature of the interactions is directly connected to the abundance distribution, and some characteristic behaviors, such as multiple peaks in the abundance distribution and all species coexistence at moderate values of $u$, are discovered in a wide class of the distribution of the interactions. The all species coexistence collapses at a critical value of $u$, $u_c$, and this collapsing is regarded as a phase transition. To get more quantitative information, we also construct a non-perturbative theory on random graphs based on techniques of statistical mechanics. The result shows those characteristic behavior...

  19. La and Eu Abundances in Metal-poor Halo Stars

    Science.gov (United States)

    Cardillo, Harrison; Burris, Debra L.

    2016-01-01

    Elements with atomic number greater than Z=26 (the Iron Peak) cannot be formed through fusion in a star's core; the majority of these elements are produced through one of two neutron-capture processes. Early in the history of the Galaxy, the rapid neutron-capture process (r-process) is believed to be responsible for the production of elements Z=56 and beyond. These elements require at least one generation of stars to have completed their life cycle in order to be synthesized. Therefore, if we observe the heavy metal abundances in what are called Population II stars (metal-poor stars), then we can begin to make inferences about the chemistry of the earliest stars in the Galaxy. To contribute to this picture of the early universe, the Lanthanum and Europium abundances of low-metallicity stars will be measured and trends in these abundances based on comparisons to existing related literature will be sought.

  20. Latitudinal patterns in the abundance of major marine bacterioplankton groups

    DEFF Research Database (Denmark)

    Wietz, Matthias; Gram, Lone; Jørgensen, Bo

    2010-01-01

    This study describes the abundance of major marine bacterioplankton taxa and two bacterial genera (Pseudoalteromonas and Vibrio) in surface seawater at 24 stations around the world. Catalyzed Reporter Deposition-Fluorescence in situ Hybridization (CARD-FISH) showed that Alphaproteobacteria (average...... relative abundance 37%, average absolute abundance 3.7×105 cells mL-1) including SAR11 (30%/3×105), Gammaproteobacteria (14%/1.2×105), and Bacteroidetes (12%/1.3×105) globally dominated the bacterioplankton. The SAR86 clade (4.6%/4.1×104) and Actinobacteria (4.5%/4×104) were detected ubiquitously, whereas...... oceans underlined the presence of biogeographical patterns among marine bacteria and the influence of environmental parameters on bacterial distribution....

  1. Abundance of atomic carbon /C I/ in dense interstellar clouds

    Science.gov (United States)

    Phillips, T. G.; Huggins, P. J.

    1981-01-01

    The abundance of interstellar neutral atomic carbon is investigated by means of its ground state fine-structure line emission at 492 GHz using the 91.5 cm telescope of NASAs Kuiper Airborne Observatory. Atomic carbon is found to be very abundant in dense interstellar molecular clouds with column densities of about 10 to the 19th per sq cm. Because the observations have considerably greater column densities than current theories of carbon chemistry, it is suggested that the physical conditions of these clouds are not as simple as assumed in the models. Various situations are discussed which would lead to large C I abundances, including the possibility that the chemical lifetimes of the clouds are relatively short.

  2. Carbon abundances of sdO stars from SPY

    Science.gov (United States)

    Hirsch, Heiko; Heber, Uli

    2009-06-01

    Ströer et al. (2007) recently suggested a classification of sdOs according to supersolar and subsolar helium abundances, with only the helium-enriched stars showing signes of carbon and/or nitrogen in their optical spectra. We aim to derive reliable carbon and nitrogen abundances by fitting synthetic spectra to data obtained with the UVES spectrograph at ESO. Here we present our first results of the analysis of carbon abundances in hot subdwarf O stars. By constructing a grid of model atmospheres consisting of hydrogen, helium and carbon we were able to derive atmospheric parameters of nine carbon rich sdOs. We find log(NC/Ntotal) up to ten times higher than the solar value, while the mean value for the effective temperature and the surface gravity is slightly lower than derived by helium-hydrogen models only. Surprisingly, we also find three fast rotators among our program stars.

  3. O, Na, Ba and Eu abundance patterns in open clusters

    CERN Document Server

    MacLean, B T; Lattanzio, J

    2014-01-01

    Open clusters are historically regarded as single-aged stellar populations representative of star formation within the Galactic disk. Recent literature has questioned this view, based on discrepant Na abundances relative to the field, and concerns about the longevity of bound clusters contributing to a selection bias: perhaps long-lived open clusters are chemically different to the star formation events that contributed to the Galactic disk. We explore a large sample of high resolution Na, O, Ba & Eu abundances from the literature, homogenized as much as reasonable including accounting for NLTE effects, variations in analysis and choice of spectral lines. Compared to a template globular cluster and representative field stars, we find no significant abundance trends, confirming that the process producing the Na-O anti-correlation in globular clusters is not present in open clusters. Furthermore, previously reported Na-enhancement of open clusters is found to be an artefact of NLTE effects, with the open cl...

  4. Elemental abundances of intermediate age open cluster NGC 3680

    CERN Document Server

    Mitschang, A W; Zucker, D B

    2012-01-01

    We present a new abundance analysis of the intermediate age Galactic open cluster NGC 3680, based on high resolution, high signal-to-noise VLT/UVES spectroscopic data. Several element abundances are presented for this cluster for the first time, but most notably we derive abundances for the light and heavy s-process elements Y, Ba, La, and Nd. The serendipitous measurement of the rare-earth r-process element Gd is also reported. This cluster exhibits a significant enhancement of Na in giants as compared to dwarfs, which may be a proxy for an O to Na anti-correlation as observed in Galactic globular clusters but not open clusters. We also observe a step-like enhancement of heavy s-process elements towards higher atomic number, contrary to expectations from AGB nucleosynthesis models, suggesting that the r-process played a significant role in the generation of both La and Nd in this cluster

  5. Oxygen Abundance Methods in SDSS: View from Modern Statistics

    Indian Academy of Sciences (India)

    Fei Shi; Gang Zhao; James Wicker

    2010-09-01

    Our purpose is to find which is the most reliable one among various oxygen abundance determination methods. We will test the validity of several different oxygen abundance determination methods using methods of modern statistics. These methods include Bayesian analysis and information scoring. We will analyze a sample of ∼ 6000 HII galaxies from the Sloan Digital Sky Survey (SDSS) spectroscopic observations data release four. All methods that we used drew the same conclusion that the method is a more reliable oxygen abundance determination method than the Bayesian metallicity method under the existing telescope ability. The ratios of the likelihoods between the different kinds of methods tell us that the , , and 32 methods are consistent with each other because the and 32 methods are calibrated by method. The Bayesian and 23 methods are consistent with each other because both are calibrated by a galaxy model. In either case, the 2 method is an unreliable method.

  6. Accurate Enthalpies of Formation of Astromolecules: Energy, Stability and Abundance

    CERN Document Server

    Etim, Emmanuel E

    2016-01-01

    Accurate enthalpies of formation are reported for known and potential astromolecules using high level ab initio quantum chemical calculations. A total of 130 molecules comprising of 31 isomeric groups and 24 cyanide/isocyanide pairs with atoms ranging from 3 to 12 have been considered. The results show an interesting, surprisingly not well explored, relationship between energy, stability and abundance (ESA) existing among these molecules. Among the isomeric species, isomers with lower enthalpies of formation are more easily observed in the interstellar medium compared to their counterparts with higher enthalpies of formation. Available data in literature confirm the high abundance of the most stable isomer over other isomers in the different groups considered. Potential for interstellar hydrogen bonding accounts for the few exceptions observed. Thus, in general, it suffices to say that the interstellar abundances of related species are directly proportional to their stabilities. The immediate consequences of ...

  7. Metaproteomics reveals abundant transposase expression in mutualistic endosymbionts

    Energy Technology Data Exchange (ETDEWEB)

    Kleiner, Manuel [Max Planck Institute for Marine Microbiology; Young, Jacque C [ORNL; Shah, Manesh B [ORNL; Verberkmoes, Nathan C [ORNL; Dubilier, Nicole [Max Planck Institute for Marine Microbiology

    2013-01-01

    Transposases, enzymes that catalyze the movement of mobile genetic elements, are the most abundant genes in nature. While many bacteria encode an abundance of transposases in their genomes, the current paradigm is that transposase gene expression is tightly regulated and generally low due to its severe mutagenic effects. In the current study, we detected the highest number of transposase proteins ever reported in bacteria, in symbionts of the gutless marine worm Olavius algarvensis using metaproteomics. At least 26 different transposases from 12 different families were detected and genomic and proteomic analyses suggest many of these are active. This high expression of transposases indicates that the mechanisms for their tight regulation have been disabled or destroyed. Based on recent studies on other symbionts and pathogens that showed high transposase transcription, we speculate that abundant transposase expression might be common in symbionts and pathogens.

  8. Ultracold neutral plasmas

    Science.gov (United States)

    Lyon, M.; Rolston, S. L.

    2017-01-01

    By photoionizing samples of laser-cooled atoms with laser light tuned just above the ionization limit, plasmas can be created with electron and ion temperatures below 10 K. These ultracold neutral plasmas have extended the temperature bounds of plasma physics by two orders of magnitude. Table-top experiments, using many of the tools from atomic physics, allow for the study of plasma phenomena in this new regime with independent control over the density and temperature of the plasma through the excitation process. Characteristic of these systems is an inhomogeneous density profile, inherited from the density distribution of the laser-cooled neutral atom sample. Most work has dealt with unconfined plasmas in vacuum, which expand outward at velocities of order 100 m/s, governed by electron pressure, and with lifetimes of order 100 μs, limited by stray electric fields. Using detection of charged particles and optical detection techniques, a wide variety of properties and phenomena have been observed, including expansion dynamics, collective excitations in both the electrons and ions, and collisional properties. Through three-body recombination collisions, the plasmas rapidly form Rydberg atoms, and clouds of cold Rydberg atoms have been observed to spontaneously avalanche ionize to form plasmas. Of particular interest is the possibility of the formation of strongly coupled plasmas, where Coulomb forces dominate thermal motion and correlations become important. The strongest impediment to strong coupling is disorder-induced heating, a process in which Coulomb energy from an initially disordered sample is converted into thermal energy. This restricts electrons to a weakly coupled regime and leaves the ions barely within the strongly coupled regime. This review will give an overview of the field of ultracold neutral plasmas, from its inception in 1999 to current work, including efforts to increase strong coupling and effects on plasma properties due to strong coupling.

  9. First Stellar Abundances in the Dwarf Irregular Galaxy IC 1613

    Science.gov (United States)

    Tautvaišienė, Gražina; Geisler, Doug; Wallerstein, George; Borissova, Jura; Bizyaev, Dmitry; Pagel, Bernard E. J.; Charbonnel, Corinne; Smith, Verne

    2007-12-01

    Chemical abundances in three M supergiants in the Local Group dwarf irregular galaxy IC 1613 have been determined using high-resolution spectra obtained with the UVES spectrograph on the ESO 8.2 m Kueyen telescope. A detailed synthetic-spectrum analysis has been used to determine the atmospheric parameters and abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, Cr, Fe, Co, Ni, La, and Eu. We find the overall metallicity of the stars to be [Fe/H] = -0.67 ± 0.09 and the age 9-13 Myr, which is in excellent agreement with the present-day values in the age-metallicity relationship model of IC 1613 by Skillman et al. We have found that the three supergiants investigated have a mean [α/Fe] equal to about -0.1, which is lower than seen in Galactic stars at the same metallicity and is in agreement with the results obtained in other dwarf irregular galaxies. The oxygen abundances are in agreement with the upper values of the nebular oxygen determinations in IC 1613. The abundance ratios of s- and r-process elements to iron are enhanced relative to solar by about 0.3 dex. The abundance pattern of the elements studied is similar to that of the Small Magellanic Cloud, except for Co and Ni, which are underabundant in the SMC. The observed elemental abundances are generally in very good agreement with the recent chemical evolution model of Yuk and Lee. Based on observations collected with the Very Large Telescope and the 2.2 m Telescope of the European Southern Observatory within the Observing Programs 70.B-0361(A) and 072.D-0113(D).

  10. Mangroves Enhance Reef Fish Abundance at the Caribbean Regional Scale.

    Directory of Open Access Journals (Sweden)

    Joseph E Serafy

    Full Text Available Several studies conducted at the scale of islands, or small sections of continental coastlines, have suggested that mangrove habitats serve to enhance fish abundances on coral reefs, mainly by providing nursery grounds for several ontogenetically-migrating species. However, evidence of such enhancement at a regional scale has not been reported, and recently, some researchers have questioned the mangrove-reef subsidy effect. In the present study, using two different regression approaches, we pursued two questions related to mangrove-reef connectivity at the Caribbean regional scale: (1 Are reef fish abundances limited by mangrove forest area?; and (2 Are mean reef fish abundances proportional to mangrove forest area after taking human population density and latitude into account? Specifically, we tested for Caribbean-wide mangrove forest area effects on the abundances of 12 reef fishes that have been previously characterized as "mangrove-dependent". Analyzed were data from an ongoing, long-term (20-year citizen-scientist fish monitoring program; coastal human population censuses; and several wetland forest information sources. Quantile regression results supported the notion that mangrove forest area limits the abundance of eight of the 12 fishes examined. Linear mixed-effects regression results, which considered potential human (fishing and habitat degradation and latitudinal influences, suggested that average reef fish densities of at least six of the 12 focal fishes were directly proportional to mangrove forest area. Recent work questioning the mangrove-reef fish subsidy effect likely reflects a failure to: (1 focus analyses on species that use mangroves as nurseries, (2 consider more than the mean fish abundance response to mangrove forest extent; and/or (3 quantitatively account for potentially confounding human impacts, such as fishing pressure and habitat degradation. Our study is the first to demonstrate at a large regional scale (i

  11. The Map of 3He Abundance for the Moon Nearside

    Science.gov (United States)

    Kaydash, V. G.; Shkuratov, Yu. G.; Starukhina, L. V.

    1999-09-01

    In [1] strong correlation between 3He content in the lunar soils and the product of the soil maturity Is/FeO upon the content of TiO2 has been presented. Using this correlation we mapped the abundance of 3He for the nearside of the Moon. For this purpose the maps [2] of the maturity degree Is/FeO and abundance of titanium in the regolith of visible hemisphere were taken. The greatest 3He abundance is predicted for the west part of mare Serenitatis (16-20 ppb) associated with ilmenite basalts areas. The lowest 3He (1-5 ppb) is characteristic of the north and south highlands. As 3He is implanted by solar wind, the variation of its average normal flux with latitude and longitude of a lunar site could affect the 3He abundance. If so, 3He content near the poles should be less than that in equatorial zones. However, 3He content is controlled by degassing rates, which is proved by great difference between the abundance ratios of the gases in solar wind and in lunar soils [3]. Moreover, lower temperature in polar regions prevent degassing so effectively that even higher 3He content can be predicted there. As a first approximation we did not take the latitude and longitude dependence of 3He abundance into account. Refs.: [1] Taylor L.A. Engr., constr., & Oper. In Space IV, Proc. of Space'94, 678. [2] Shkuratov Yu.G. et al. 1999. Icarus, 137, 222-234. [3] Haskin L., Warren P. Lunar chemistry. Lunar sourcebook. /Eds. Heiken G. H. et al.. N. Y., 1991. 357-474.

  12. A Comparison of Stellar Elemental Abundance Techniques and Measurements

    Science.gov (United States)

    Hinkel, Natalie R.; Young, Patrick A.; Pagano, Michael D.; Desch, Steven J.; Anbar, Ariel D.; Adibekyan, Vardan; Blanco-Cuaresma, Sergi; Carlberg, Joleen K.; Delgado Mena, Elisa; Liu, Fan; Nordlander, Thomas; Sousa, Sergio G.; Korn, Andreas; Gruyters, Pieter; Heiter, Ulrike; Jofré, Paula; Santos, Nuno C.; Soubiran, Caroline

    2016-09-01

    Stellar elemental abundances are important for understanding the fundamental properties of a star or stellar group, such as age and evolutionary history, as well as the composition of an orbiting planet. However, as abundance measurement techniques have progressed, there has been little standardization between individual methods and their comparisons. As a result, different stellar abundance procedures determine measurements that vary beyond the quoted error for the same elements within the same stars. The purpose of this paper is to better understand the systematic variations between methods and offer recommendations for producing more accurate results in the future. We invited a number of participants from around the world (Australia, Portugal, Sweden, Switzerland, and the United States) to calculate 10 element abundances (C, O, Na, Mg, Al, Si, Fe, Ni, Ba, and Eu) using the same stellar spectra for four stars (HD 361, HD 10700, HD 121504, and HD 202206). Each group produced measurements for each star using (1) their own autonomous techniques, (2) standardized stellar parameters, (3) a standardized line list, and (4) both standardized parameters and a line list. We present the resulting stellar parameters, absolute abundances, and a metric of data similarity that quantifies the homogeneity of the data. We conclude that standardization of some kind, particularly stellar parameters, improves the consistency between methods. However, because results did not converge as more free parameters were standardized, it is clear there are inherent issues within the techniques that need to be reconciled. Therefore, we encourage more conversation and transparency within the community such that stellar abundance determinations can be reproducible as well as accurate and precise.

  13. Relationships between sedimentary subseafloor microbial abundance and sedimentation rate

    Science.gov (United States)

    Kallmeyer, J.

    2015-12-01

    Cell count data for estimates of global subseafloor microbial abundance need to be simplified in order to be used for model calculations All models rely on regressions of cell counts vs. depth. Different strategies are being used for simplifying the data, e.g. averaging over highly variable data from different oceanic provinces or excluding individual datasets that cannot be described by a single regression. While providing global estimates, these models fail to identify the finer details of the controls on subseafloor microbial abundance. Most subseafloor microbes are heterotrophic and gain energy by degrading buried organic matter. Because sedimentation rate is usually positively correlated with primary productivity and organic matter flux to the seafloor, it determines how much organic matter is deposited on the sea floor and how fast it is buried and reaches greater depths. At the same depth, in environments with low sed. rates the organic matter is older, more degraded and supports less metabolic activity than in those with high sed. rates. As a result, sed. rates control penetration depth of oxygen and other electron acceptors. Oxygen penetration remains in the mm to cm range over most sed. rates and it only penetrates significantly deeper at very low rates of ca. 1 mm/kyr or less. However, microbial abundance correlates with sed. rate over a wider range. In order to take a more detailed look at the influence of sed. rate and therefore sediment age on cell abundance, ages and additional geochemical information were assigned to individual cell counts. The new dataset shows the strong influence of sed. rates or rather sediment age on microbial abundance, while oxygen concentrations seem to have only a minor influence. Using data from IODP drill sites that have moved from high to low productivity zones or vice versa helps to differentiate between different factors that control microbial cell abundance.

  14. The decoupling of abundance and species richness in lizard communities.

    Science.gov (United States)

    Nimmo, Dale G; James, Simon G; Kelly, Luke T; Watson, Simon J; Bennett, Andrew F

    2011-05-01

    1. Patterns of species richness often correlate strongly with measures of energy. The more individuals hypothesis (MIH) proposes that this relationship is facilitated by greater resources supporting larger populations, which are less likely to become extinct. Hence, the MIH predicts that community abundance and species richness will be positively related. 2. Recently, Buckley & Jetz (2010, Journal of Animal Ecology, 79, 358-365) documented a decoupling of community abundance and species richness in lizard communities in south-west United States, such that richer communities did not contain more individuals. They predicted, as a consequence of the mechanisms driving the decoupling, a more even distribution of species abundances in species-rich communities, evidenced by a positive relationship between species evenness and species richness. 3. We found a similar decoupling of the relationship between abundance and species richness for lizard communities in semi-arid south-eastern Australia. However, we note that a positive relationship between evenness and richness is expected because of the nature of the indices used. We illustrate this mathematically and empirically using data from both sets of lizard communities. When we used a measure of evenness, which is robust to species richness, there was no relationship between evenness and richness in either data set. 4. For lizard communities in both Australia and the United States, species dominance decreased as species richness increased. Further, with the iterative removal of the first, second and third most dominant species from each community, the relationship between abundance and species richness became increasingly more positive. 5. Our data support the contention that species richness in lizard communities is not directly related to the number of individuals an environment can support. We propose an alternative hypothesis regarding how the decoupling of abundance and richness is accommodated; namely, an inverse

  15. Baade's window and APOGEE. Metallicities, ages, and chemical abundances

    Science.gov (United States)

    Schultheis, M.; Rojas-Arriagada, A.; García Pérez, A. E.; Jönsson, H.; Hayden, M.; Nandakumar, G.; Cunha, K.; Allende Prieto, C.; Holtzman, J. A.; Beers, T. C.; Bizyaev, D.; Brinkmann, J.; Carrera, R.; Cohen, R. E.; Geisler, D.; Hearty, F. R.; Fernandez-Tricado, J. G.; Maraston, C.; Minnitti, D.; Nitschelm, C.; Roman-Lopes, A.; Schneider, D. P.; Tang, B.; Villanova, S.; Zasowski, G.; Majewski, S. R.

    2017-04-01

    Context. Baade's window (BW) is one of the most observed Galactic bulge fields in terms of chemical abundances. Owing to its low and homogeneous interstellar absorption it is considered the perfect calibration field for Galactic bulge studies. Aims: In the era of large spectroscopic surveys, calibration fields such as BW are necessary for cross calibrating the stellar parameters and individual abundances of the APOGEE survey. Methods: We use the APOGEE BW stars to derive the metallicity distribution function (MDF) and individual abundances for α- and iron-peak elements of the APOGEE ASPCAP pipeline (DR13), as well as the age distribution for stars in BW. Results: We determine the MDF of APOGEE stars in BW and find a remarkable agreement with that of the Gaia-ESO survey (GES). Both exhibit a clear bimodal distribution. We also find that the Mg-metallicity planes of the two surveys agree well, except for the metal-rich part ([Fe/H] > 0.1), where APOGEE finds systematically higher Mg abundances with respect to the GES. The ages based on the [C/N] ratio reveal a bimodal age distribution, with a major old population at 10 Gyr, with a decreasing tail towards younger stars. A comparison of stellar parameters determined by APOGEE and those determined by other sources reveals detectable systematic offsets, in particular for spectroscopic surface gravity estimates. In general, we find a good agreement between individual abundances of O, Na, Mg, Al, Si, K, Ca, Cr, Mn, Co, and Ni from APOGEE with that of literature values. Conclusions: We have shown that in general APOGEE data show a good agreement in terms of MDF and individual chemical abundances with respect to literature works. Using the [C/N] ratio we found a significant fraction of young stars in BW.

  16. Sulfur and zinc abundances of red giant stars†

    Science.gov (United States)

    Takeda, Yoichi; Omiya, Masashi; Harakawa, Hiroki; Sato, Bun'ei

    2016-10-01

    Sulfur and zinc are chemically volatile elements, which play significant roles as depletion-free tracers in studying galactic chemical evolution. However, regarding red giants having evolved off the main sequence, reliable abundance determinations of S and Zn seem to be difficult, despite the several studies that have been reported so far. Given this situation, we tried to establish the abundances of these elements for an extensive sample of 239 field GK giants ( - 0.8 ≲ [Fe/H] ≲ +0.2), by applying the spectrum-fitting technique to S I 8694-5, S I 6757, and Zn I 6362 lines and by taking into account the non-LTE effect. Besides, similar abundance analysis was done for 160 FGK dwarfs to be used for comparison. The non-LTE corrections for the S and Zn abundances derived from these lines turned out to be ≲ 0.1(-0.2) dex for most cases and not very significant. It revealed that the S I 6757 feature is more reliable as an abundance indicator than S I 8694-5 for the case of red giants, because the latter suffers blending of unidentified lines. The finally resulting [S/Fe]-[Fe/H] and [Zn/Fe]-[Fe/H] relations for GK giants were confirmed to be in good agreement with those for FGK dwarfs, indicating that S and Zn abundances of red giants are reliably determinable from the S I 6757 and Zn I 6362 lines. Accordingly, not only main-sequence stars but also evolved red giant stars are usable for tracing the chemical evolution history of S and Zn in the regime of disk metallicity by using these lines.

  17. Plasma Physics An Introduction to Laboratory, Space, and Fusion Plasmas

    CERN Document Server

    Piel, Alexander

    2010-01-01

    Plasma Physics gives a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The new fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a brief introduction to plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple and emphasizes the underlying concepts. T...

  18. Chemical Abundances for Seven Giant Stars in M68 (NGC 4590) A Globular Cluster with Abnormal Silicon and Titanium Abundances

    CERN Document Server

    Lee, J W; Habgood, M J; Lee, Jae-Woo; Carney, Bruce W.

    2004-01-01

    We present a detailed chemical abundance study of seven giant stars in M68 including six red giants and one post-AGB star. We find significant differences in the gravities determined using photometry and those obtained from ionization balance, which suggests that non-LTE effects are important for these low-gravity, metal-poor stars. We adopt an iron abundance using photometric gravities and Fe II lines to minimize those effects, finding [Fe/H] = -2.16 +/- 0.02. For element-to-iron ratios,we rely on neutral lines vs. Fe I and ionized lines vs. FeII (except for [O/Fe]) to also minimize non-LTE effects. We find variations in the abundances of sodium among the program stars. However, there is no correlation (or anti-correlation) with the oxygen abundances. Further, the post-AGB star has a normal (low) abundance of sodium. Both of these facts add further support to the idea that the variations seen among some light elements within individual globular clusters arises from primordial variations, and not from deep mi...

  19. Fe-peak element abundances in disk and halo stars

    CERN Document Server

    Bergemann, Maria

    2009-01-01

    At present none of Galactic chemical evolution (GCE) models provides a self-consistent description of observed trends for all iron-peak elements with metallicity simultaneously. The question is whether the discrepancy is due to deficiencies of GCE models, such as stellar yields, or due to erroneous spectroscopically-determined abundances of these elements in metal-poor stars. The present work aims at a critical reevaluation of the abundance trends for several odd and even-Z Fe-peak elements, which are important for understanding explosive nucleosynthesis in supernovae.

  20. Suppressing the QCD axion abundance by hidden monopoles

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Masahiro [Tokyo Univ., Chiba (Japan). Inst. for Cosmic Ray Research; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Takahashi, Fuminobu [Tokyo Univ., Miyagi (Japan). Dept. of Physics; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Yamada, Masaki [Tokyo Univ., Chiba (Japan). Inst. for Cosmic Ray Research; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; DESY Hamburg (Germany)

    2015-11-15

    We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 10{sup 12} GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei-Quinn symmetry is spontaneously broken after inflation.

  1. Suppressing the QCD axion abundance by hidden monopoles

    Directory of Open Access Journals (Sweden)

    Masahiro Kawasaki

    2016-02-01

    Full Text Available We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 1012GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei–Quinn symmetry is spontaneously broken after inflation.

  2. Asteroseismic estimate of helium abundance of 16 Cyg A, B

    Directory of Open Access Journals (Sweden)

    Verma Kuldeep

    2015-01-01

    Full Text Available The helium ionization zone in a star leaves a characteristic signature on its oscillation frequencies, which can be used to estimate the helium content in the envelope of the star. We use the oscillation frequencies of 16 Cyg A and B, obtained using 2.5 years of Kepler data, to estimate the envelope helium abundance of these stars. We find the envelope helium abundance to lie in the range 0.231–0.251 for 16 Cyg A and 0.218–0.266 for 16 Cyg B.

  3. Carbon Abundances in the Small Magellanic Cloud Planetary Nebulae

    CERN Document Server

    Lee, T H; Shaw, R A; Balick, B; Villaver, E

    2006-01-01

    As an ongoing study of Magellanic Cloud PNe we have obtained UV spectra of 9 PNe in the SMC to measure their carbon abundances. The spectra have been acquired with ACS HRC/PR200L and SBC/PR130L. The ACS prisms give a reasonable resolution in the range of 1200 -- 2500 A to detect the C IV, C III], and C II] nebular emission, essential for chemical studies of the PNe. The carbon abundances of SMC PNe, together with those of the LMC previously determined with STIS spectroscopy, will allow a comparative study of nebular enrichment and provide the basis for comparison with stellar evolution models at various metallicity.

  4. New functionalities in abundant element oxides: ubiquitous element strategy.

    Science.gov (United States)

    Hosono, Hideo; Hayashi, Katsuro; Kamiya, Toshio; Atou, Toshiyuki; Susaki, Tomofumi

    2011-06-01

    While most ceramics are composed of ubiquitous elements (the ten most abundant elements within the Earth's crust), many advanced materials are based on rare elements. A 'rare-element crisis' is approaching owing to the imbalance between the limited supply of rare elements and the increasing demand. Therefore, we propose a 'ubiquitous element strategy' for materials research, which aims to apply abundant elements in a variety of innovative applications. Creation of innovative oxide materials and devices based on conventional ceramics is one specific challenge. This review describes the concept of ubiquitous element strategy and gives some highlights of our recent research on the synthesis of electronic, thermionic and structural materials using ubiquitous elements.

  5. Dark Matter Relic Abundance and Light Sterile Neutrinos

    CERN Document Server

    Tang, Yi-Lei

    2016-01-01

    In this paper, we calculate the relic abundance of the dark matter particles when they can annihilate into sterile neutrinos with the mass $\\lesssim 100 \\text{ GeV}$ in a simple model. Unlike the usual standard calculations, the sterile neutrino may fall out of the thermal equilibrium with the thermal bath before the dark matter freezes out. In such case, if the Yukawa coupling between Higgs and sterile neutrino $y_N$ is small, this process gives rise to a larger $\\Omega_{\\text{DM}} h^2$ so we need a larger coupling between dark matter and the sterile neutrino for a correct relic abundance.

  6. Distribution and abundance of West Greenland humpback whales ( Megaptera novaeangliae )

    DEFF Research Database (Denmark)

    Larsen, Finn; Hammond, P.S.

    2004-01-01

    Photo-identification surveys of humpback whales Megaptera novaeangliae were conducted at West Greenland during 1988-93, the last 2 years of which were part of the internationally coordinated humpback whale research programme YoNAH, with the primary aim of estimating abundance for the West Greenland...... effort. A total of 670 groups of humpback whales was encountered leading to the identification of 348 individual animals. Three areas of concentration were identified: an area off Nuuk; an area at c. 63degrees30'N; and an area off Frederikshab. Sequential Petersen capture-recapture estimates of abundance...

  7. Molecular abundances in the Sagittarius A molecular cloud

    Science.gov (United States)

    Minh, Y. C.; Irvine, W. M.; Friberg, P.

    1992-01-01

    We have obtained column densities for HCO(+), HCO, HCS(+), C3H2, HC5N, SiO, OCS, HCOOH, CH3CH2OH, and CH3CCH toward Sgr A. The fractional abundance of SiO relative to molecular hydrogen in Sgr A is comparable to that for the Orion plateau, about 10 exp-7 to 10 exp -8, which may be a typical value for hot clouds. The abundances of HCO, CH3CH2OH, and CH3CCH all appear to be enhanced relative to other molecular clouds such as Sgr B2.

  8. Trace Element Abundance Measurements on Cosmic Dust Particles

    Science.gov (United States)

    Flynn, George

    1996-01-01

    The X-Ray Microprobe on beamline X-26A at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory was used to determine the abundances of elements from Cr through Sr in individual interplanetary dust particles (IDPs) collected from the Earth's stratosphere and the Scanning Transmission X-ray Microscope (STXM) on beamline X-1A at the NSLS was used to determine the carbon abundances and spatial distributions in IDPs. In addition, modeling was performed in an attempt to associate particular types of IDPs with specific types of parent bodies, and thus to infer the chemistry, mineralogy, and structural properties of those parent bodies.

  9. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up

  10. [Acute plasma cell leukemia].

    Science.gov (United States)

    Monsalbe, V; Domíngues, C; Roa, I; Busel, D; González, S

    1989-01-01

    Plasma Cell Leukemia is a very rare form of plasmocytic dyscrasia, whose clinical and pathological characteristics warrant its recognition as a distinct subentity. We report the case of a 60 years old man who presented a rapidly fatal acute plasma cell leukemia, with multiple osteolytic lesions, hipercalcemia, renal and cardiac failure.

  11. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Takashi [Department of Engineering Physics and Mechanics, Graduate School of Engineering, Kyoto University, Kyoto (Japan)

    2000-03-01

    Polarization of radiation emitted from a plasma reflects the anisotropic properties of the plasma, especially the angular anisotropic distribution of electron velocities. Polarization has been observed on impurity ion lines from the WT-3 tokamak and the GAMMA-10 tandem mirror machines. The soft x-ray laser line from the neonlike germanium was also found polarized. (author)

  12. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Iwamae, Atsushi; Inoue, Takeru; Tanaka, Akihiro; Kawakami, Kazuki; Fujimoto, Takashi [Kyoto Univ., Dept. of Engineering Physics, Kyoto (Japan)

    2000-03-01

    Polarization of radiation emitted from plasma reflects the anisotropic properties of the plasma, especially the angular isotropic distribution of electron velocities. Polarization has been observed on impurity ion lines from the WT-3 tokamak and GAMMA 10 tandem mirror device. (author)

  13. Atoms in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1986-01-01

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.

  14. Plasma etching an introduction

    CERN Document Server

    Manos, Dennis M

    1989-01-01

    Plasma etching plays an essential role in microelectronic circuit manufacturing. Suitable for researchers, process engineers, and graduate students, this book introduces the basic physics and chemistry of electrical discharges and relates them to plasma etching mechanisms. Throughout the volume the authors offer practical examples of process chemistry, equipment design, and production methods.

  15. Modelling of Complex Plasmas

    NARCIS (Netherlands)

    Akdim, M.R. (Mohamed Reda)

    2003-01-01

    Nowadays plasmas are used for various applications such as the fabrication of silicon solar cells, integrated circuits, coatings and dental cleaning. In the case of a processing plasma, e.g. for the fabrication of amorphous silicon solar cells, a mixture of silane and hydrogen gas is injected in a r

  16. "Angular" plasma cell cheilitis.

    Science.gov (United States)

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida, Hiram Larangeira; Lorencette, Nádia Aparecida; Netto, José Fillus

    2014-03-17

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  17. "Angular" plasma cell cheilitis

    OpenAIRE

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida Jr, Hiram Larangeira; Lorencette, Nadia Aparecida; Netto, Jose Fillus

    2014-01-01

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  18. Introduction to Plasma Spectroscopy

    CERN Document Server

    Kunze, H-J

    2009-01-01

    Based on lectures given at the Ruhr-University of Bochum for graduate students and postgraduates starting in plasma physics as well as from low- to high-density hot plasmas, this book introduces basic ideas and fundamental concepts and typical instrumentation from the X-ray to the infrared spectral regions

  19. Innovations in plasma sensors

    Science.gov (United States)

    Zurbuchen, Thomas H.; Gershman, Daniel J.

    2016-04-01

    During the history of space exploration, ever improving instruments have continued to enable new measurements and discoveries. Focusing on plasma sensors, we examine the processes by which such new instrument innovations have occurred over the past decades. Due to risk intolerance prevalent in many NASA space missions, innovations in plasma instrumentation occur primarily when heritage systems fail to meet science requirements, functional requirements as part of its space platform, or design constraints. We will review such innovation triggers in the context of the design literature and with the help of two case studies, the Fast Imaging Plasma Spectrometer on MErcury Surface, Space ENvironment, GEochemistry, and Ranging and the Fast Plasma Investigation on Magnetosphere Multiscale. We will then discuss the anticipated needs for new plasma instrument innovations to enable the science program of the next decade.

  20. Wakes in inhomogeneous plasmas

    CERN Document Server

    Kompaneets, Roman; Nosenko, Vladimir; Morfill, Gregor E

    2014-01-01

    The Debye shielding of a charge immersed in a flowing plasma is an old classic problem in plasma physics. It has been given renewed attention in the last two decades in view of experiments with complex plasmas, where charged dust particles are often levitated in a region with strong ion flow. Efforts to describe the shielding of the dust particles in such conditions have been focused on the homogeneous plasma approximation, which ignores the substantial inhomogeneity of the levitation region. We address the role of the plasma inhomogeneity by rigorously calculating the point charge potential in the collisionless Bohm sheath. We demonstrate that the inhomogeneity can dramatically modify the wake, making it non-oscillatory and weaker.

  1. Basic plasma physics

    CERN Document Server

    Ghosh, Basudev

    2014-01-01

    Basic Plasma Physics is designed to serve as an introductory compact textbook for advanced undergraduate, postgraduate and research students taking plasma physics as one of their subject of study for the first time. It covers the current syllabus of plasma physics offered by the most universities and technical institutions. The book requires no background in plasma physics but only elementary knowledge of basic physics and mathematics. Emphasis has been given on the analytical approach. Topics are developed from first principle so that the students can learn through self-study. One chapter has been devoted to describe some practical aspects of plasma physics. Each chapter contains a good number of solved and unsolved problems and a variety of review questions, mostly taken from recent examination papers. Some classroom experiments described in the book will surely help students as well as instructors.

  2. Microphysics of cosmic plasmas

    CERN Document Server

    Bykov, Andrei; Cargill, Peter; Dendy, Richard; Wit, Thierry; Raymond, John

    2014-01-01

    This title presents a review of the detailed aspects of the physical processes that underlie the observed properties, structures and dynamics of cosmic plasmas. An assessment of the status of understanding of microscale processes in all astrophysical collisionless plasmas is provided. The topics discussed include  turbulence in astrophysical and solar system plasmas as a phenomenological description of their dynamic properties on all scales; observational, theoretical and modelling aspects of collisionless magnetic reconnection; the formation and dynamics of shock waves; and a review and assessment of microprocesses, such as the hierarchy of plasma instabilities, non-local and non-diffusive transport processes and ionisation and radiation processes.  In addition, some of the lessons that have been learned from the extensive existing knowledge of laboratory plasmas as applied to astrophysical problems are also covered.   This volume is aimed at graduate students and researchers active in the areas of cosmi...

  3. SUPERFAST THERMALIZATION OF PLASMA

    Science.gov (United States)

    Chang, C.C.

    1962-06-12

    A method is given for the superfast thermalization of plasma by shock conversion of the kinetic energy stored in rotating plasma rings or plasmoids colliding at near supersonic speeds in a containment field to heat energy in the resultant confined plasma mass. The method includes means for generating rotating plasmoids at the opposite ends of a Pyrotron or Astron containment field. The plasmoids are magnetically accelerated towards each other into the opposite ends of time containment field. During acceleration of the plasmoids toward the center of the containment field, the intensity of the field is sequentially increased to adiabatically compress the plasmoids and increase the plasma energy. The plasmoids hence collide with a violent shock at the eenter of the containment field, causing the substantial kinetic energy stored in the plasmoids to be converted to heat in the resultant plasma mass. (AEC)

  4. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike

    2008-01-01

    as reactive splvent (as shown in Figure 1). 1] H. Biederman, in Plasma Polymer Films. (ed.) H. Biederman. Imperial College Press, Singapore, 13-24 ~OO~· '. , [2] R. d'Agostino et.a!. in Plasma Depd~itiqn, 'Treatment, and Etching ofPolymers. (ed.) R. d'Agostino, Academic Press, U.S. (1990). [3] F. F. Shi......In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode......, external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous...

  5. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Phadnaik Mangesh

    2010-01-01

    Full Text Available Plasma cell granuloma is a rare reactive lesion composed of polyclonal plasma cells. It manifests primarily in the lungs, but may occur in various other anatomic locations like the oral cavity. Intraoral plasma cell granulomas involving the tongue, lip, oral mucosa and gingiva have been reported in the past. This case presents a 54-year-old female with chronic periodontitis and mandibular anterior gingival overgrowth treated by Phase I therapy (scaling and root planing and excisional biopsy. Histological examination revealed inflammatory cell infiltrate containing sheets of plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma. This case highlights the need to biopsy for unusual lesions to rule out potential neoplasms.

  6. Helical plasma thruster

    Energy Technology Data Exchange (ETDEWEB)

    Beklemishev, A. D., E-mail: bekl@bk.ru [Budker Institute of Nuclear Physics SB RAS, Novosibirsk (Russian Federation)

    2015-10-15

    A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR{sup ®} rocket engine.

  7. Diagnostics of Nanodusty Plasma

    Science.gov (United States)

    Greiner, Franko; Groth, Sebastian; Tadsen, Bejamin; Piel, Alexander

    2015-11-01

    The diagnostic of nanodusty plasmas, i.e. plasmas including nano-sized dust particles, is a challenging task. For both, the diagnostic of the nanodusty plasma itself, and the in-situ diagnostic of the nanoparticles, no standard diagnostic exist. Nanodust particle size and density can be estimated using light scattering techniques, namely kinetic Mie ellipsometry and extinction measurements. The charge of the nanoparticles can be estimated from the analysis of dust density waves (DDW). Parameters like the electron density, which give information about the plasma itself, may be deduced from the DDW analysis. We present detailed investigations on nanodust in a reactive Argon-Acetylene plasma created in an rf-driven parallel plate reactor at low pressure using the above mentioned portfolio of diagnostic. Funded by DFG under contract SFB TR-24/A2.

  8. Solar system plasma waves

    Science.gov (United States)

    Gurnett, Donald A.

    1995-01-01

    An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

  9. Plasmas for controlling the synthesis of semiconductor nanocrystals

    Science.gov (United States)

    Anthony, Rebecca

    2014-10-01

    Recently, nonthermal plasma synthesis of opto-electronically active semiconductor nanomaterials has attracted interest. The plasma reactor is especially attractive for synthesis of some earth-abundant and nontoxic semiconductor nanocrystals (NCs), such as silicon and gallium nitride. These materials, with high melting temperatures, are more challenging to grow using the liquid-phase techniques that are successful for other materials, such as II-VI NCs. Here, plasma synthesis of high-quality NCs from these materials will be discussed, including investigations on controlling the NCs' light emission properties via physical changes in the NCs brought about by altering the plasma parameters. For example, nanoparticle crystallinity may be controlled by altering the power supplied to the plasma reactor, which has been revealed to influence both the density of atomic hydrogen and the ion density in the plasma. In addition, the surfaces of NCs (which have been shown to be crucial in determining NC luminescence properties) can be altered utilizing reactions that take place in the plasma after NC growth is finished. The features of the plasma reactor provide unique and selective control over the properties of NCs, and also allow for deposition of dense films of NCs directly from the gas-phase, in complete avoidance of liquid-phase methods. These features - crystallization of environmentally benign materials, capacity to control NC surfaces via plasma-intiated reactions, and direct deposition of these materials onto device substrates - unite in a method for ``green'' processing of nanomaterials. Future directions for utilizing plasma reactors for nanomaterials synthesis and processing will also be discussed.

  10. Electronegative Plasma Instabilities in Industrial Pulsed Plasmas

    Science.gov (United States)

    Pribyl, Patrick; Hansen, Anders; Gekelman, Walter

    2016-10-01

    Electronegative gases that are important for industrial etch processes have a series of instabilities that occur at process relevant conditions. These have been studied since the 1990s, but are becoming a much more important today as plasma reactors are being pushed to produce ever finer features, and tight control of the etch process is becoming crucial. The experiments are being done in a plasma etch tool that closely simulates a working industrial device. ICP coils in different configurations are driven by a pulsed RF generators operating at 2-5 MHz. A computer controlled automated probe drive can access a volume above the substrate. The probe can be a Langmuir probe, a ``Bdot'' probe, or an emissive probe the latter used for more accurate determination of plasma potential. A microwave interferometer is available to measure line-averaged electron density. The negative ion instability is triggered depending upon the gas mix (Ar,SF6) , pressure and RF power. The instability can be ``burned through'' by rapidly pulsing the RF power. In this study we present measurements of plasma current and density distribution over the wafer before, after and during the rapid onset of the instability. Work suported by NSF-GOALI Award and done at the BAPSF.

  11. Relative species abundance of replicator dynamics with sparse interactions

    Science.gov (United States)

    Obuchi, Tomoyuki; Kabashima, Yoshiyuki; Tokita, Kei

    2016-11-01

    A theory of relative species abundance on sparsely-connected networks is presented by investigating the replicator dynamics with symmetric interactions. Sparseness of a network involves difficulty in analyzing the fixed points of the equation, and we avoid this problem by treating large self interaction u, which allows us to construct a perturbative expansion. Based on this perturbation, we find that the nature of the interactions is directly connected to the abundance distribution, and some characteristic behaviors, such as multiple peaks in the abundance distribution and all species coexistence at moderate values of u, are discovered in a wide class of the distribution of the interactions. The all species coexistence collapses at a critical value of u, u c , and this collapsing is regarded as a phase transition. To get more quantitative information, we also construct a non-perturbative theory on random graphs based on techniques of statistical mechanics. The result shows those characteristic behaviors are sustained well even for not large u. For even smaller values of u, extinct species start to appear and the abundance distribution becomes rounded and closer to a standard functional form. Another interesting finding is the non-monotonic behavior of diversity, which quantifies the number of coexisting species, when changing the ratio of mutualistic relations Δ . These results are examined by numerical simulations, which show that our theory is exact for the case without extinct species, but becomes less and less precise as the proportion of extinct species grows.

  12. Flow cytometric enumeration of marine viral populations at low abundances

    NARCIS (Netherlands)

    Mojica, K.D.A.; Evans, C.; Brussaard, C.P.D.

    2014-01-01

    Flow cytometric enumeration has advanced our ability to analyze aquatic virus samples and thereby our understanding of the ecological role viruses play in the oceans. However, low virus abundances are underestimated using the current flow cytometry (FCM) protocol. Our results revealed that low

  13. Terrestrial salamander abundance on reclaimed mountaintop removal mines

    Science.gov (United States)

    Wood, Petra Bohall; Williams, Jennifer M.

    2013-01-01

    Mountaintop removal mining, a large-scale disturbance affecting vegetation, soil structure, and topography, converts landscapes from mature forests to extensive grassland and shrubland habitats. We sampled salamanders using drift-fence arrays and coverboard transects on and near mountaintop removal mines in southern West Virginia, USA, during 2000–2002. We compared terrestrial salamander relative abundance and species richness of un-mined, intact forest with habitats on reclaimed mountaintop removal mines (reclaimed grassland, reclaimed shrubland, and fragmented forest). Salamanders within forests increased in relative abundance with increasing distance from reclaimed mine edge. Reclaimed grassland and shrubland habitats had lower relative abundance and species richness than forests. Characteristics of reclaimed habitats that likely contributed to lower salamander abundance included poor soils (dry, compacted, little organic matter, high rock content), reduced vertical structure of vegetation and little tree cover, and low litter and woody debris cover. Past research has shown that salamander populations reduced by clearcutting may rebound in 15–24 years. Time since disturbance was 7–28 years in reclaimed habitats on our study areas and salamander populations had not reached levels found in adjacent mature forests.

  14. Chemical Abundance Analysis of Moving Group W11450 (Latham 1)

    CERN Document Server

    O'Connell, Julia E; Frinchaboy, Peter M

    2016-01-01

    We present elemental abundances for all seven stars in Moving Group W11450 (Latham 1) to determine if they may be chemically related. These stars appear to be both spatially and kinematically related, but no spectroscopic abundance analysis exists in literature. Abundances for eight elements were derived via equivalent width analyses of high resolution (R $\\sim$60,000), high signal-to-noise ratio ($\\langle$SNR$\\rangle\\sim$100) spectra obtained with the Otto Struve 2.1m telescope and Sandiford Echelle Spectrograph at McDonald Observatory. The large star-to-star scatter in metallicity, -0.55 $\\leq$ [Fe/H] $\\leq$ 0.06 dex ($\\sigma$= 0.25), implies these stars were not produced from the same chemically homogeneous molecular cloud, and are therefore not part of a remnant or open cluster as previously proposed. Prior to this analysis, it was suggested that two stars in the group, W11449 & W11450, are possible wide binaries. The candidate wide binary pair show similar chemical abundance patterns with not only ir...

  15. Abundance of eukaryotic microbes in the deep subtropical North Atlantic

    NARCIS (Netherlands)

    Morgan-Smith, D.; Herndl, G.J.; van Aken, H.M.; Bochdansky, A.B.

    2011-01-01

    The meso- and bathypelagic ocean comprises the largest habitat on earth, yet we know very little about the distribution and activity of protists in this environment. These small eukaryotes are responsible for controlling bacterial abundance in the surface ocean and are major players in the material

  16. Dilaton could affect abundance of dark matter particles

    CERN Multimedia

    2007-01-01

    "The amount of dark matter left over from the early universe may be less than previously believed. new research shows that the "relic abundance" of stable dark matter particles such as the neutralino may be reduced as compared to standard cosmology theories due to the effects of the "dilaton", a particle with zero spin in the gravitational sector of strings." (1 page)

  17. Chemical abundances of distant extremely metal-poor unevolved stars

    CERN Document Server

    Bonifacio, P; Caffau, E; Ludwig, H -G; Spite, M; Hernández, J I González; Behara, N T

    2012-01-01

    Aims: The purpose of our study is to determine the chemical composition of a sample of 16 candidate Extremely Metal-Poor (EMP) dwarf stars, extracted from the Sloan Digital Sky Survey (SDSS). There are two main purposes: in the first place to verify the reliability of the metallicity estimates derived from the SDSS spectra; in the second place to see if the abundance trends found for the brighter nearer stars studied previously also hold for this sample of fainter, more distant stars. Methods: We used the UVES at the VLT to obtain high-resolution spectra of the programme stars. The abundances were determined by an automatic analysis with the MyGIsFOS code, with the exception of lithium, for which the abundances were determined from the measured equivalent widths of the Li I resonance doublet. Results: All candidates are confirmed to be EMP stars, with [Fe/H]<= -3.0. The chemical composition of the sample of stars is similar to that of brighter and nearer samples. We measured the lithium abundance for 12 st...

  18. Evaluating noninvasive genetic sampling techniques to estimate large carnivore abundance.

    Science.gov (United States)

    Mumma, Matthew A; Zieminski, Chris; Fuller, Todd K; Mahoney, Shane P; Waits, Lisette P

    2015-09-01

    Monitoring large carnivores is difficult because of intrinsically low densities and can be dangerous if physical capture is required. Noninvasive genetic sampling (NGS) is a safe and cost-effective alternative to physical capture. We evaluated the utility of two NGS methods (scat detection dogs and hair sampling) to obtain genetic samples for abundance estimation of coyotes, black bears and Canada lynx in three areas of Newfoundland, Canada. We calculated abundance estimates using program capwire, compared sampling costs, and the cost/sample for each method relative to species and study site, and performed simulations to determine the sampling intensity necessary to achieve abundance estimates with coefficients of variation (CV) of sampling was effective for both coyotes and bears and hair snags effectively sampled bears in two of three study sites. Rub pads were ineffective in sampling coyotes and lynx. The precision of abundance estimates was dependent upon the number of captures/individual. Our simulations suggested that ~3.4 captures/individual will result in a sampling was more cost-effective for sampling multiple species, but suggest that hair sampling may be less expensive at study sites with limited road access for bears. Given the dependence of sampling scheme on species and study site, the optimal sampling scheme is likely to be study-specific warranting pilot studies in most circumstances. © 2015 John Wiley & Sons Ltd.

  19. A complete dataset of copper for investigation of element abundance

    Science.gov (United States)

    Zeng, Jiaolong; Liu, Yanpeng; Yuan, Jianmin

    2014-05-01

    The abundance of copper plays an important role in the chemical evolution of various stars, such as giant stars and solar-type stars. Accurate determination of its abundance helps to clarify a number of problems including the quite different behavior from other Fe-peak elements both in our Galaxy and extragalactic systems and the [Cu/Fe] ratios in Galactic stars. To accurately determine the copper abundance, it is necessary to include the non-local thermodynamic equilibrium (NLTE) effects, which depend on a complete dataset of atomic data. However, the complexity of electronic structure of copper makes the accurate prediction of a complete set of atomic data difficult. For both atomic Cu and the first ionized Cu II, the energies of 3d and 4s orbitals are very close and their competition results in complex energy levels. The excitation energy of 3d orbital is very low resulting in an opening 3d atomic system which is difficult to deal with theoretically due to the strong electron correlations. We present a complete set of atomic data including the energy levels, oscillator strengths, and photoionization cross sections of Cu I for the NLTE modeling in copper abundance investigation of astrophysical objects. The calculations are performed with the R-matrix method.

  20. Fusion energy - an abundant energy source for the future

    DEFF Research Database (Denmark)

    this goal, mankind will have a sustainable base load energy source with abundant resources, having no CO2 release, and with no longlived radioactive waste. This presentation will describe the basics of fusion energy production and the status and future prospects of the research. Considerations...