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Sample records for os abcessos pulmonares

  1. [Simultaneous pulmonar, laryngeal and lingual affectation by Mycobacterium tuberculosis].

    PubMed

    Díaz Manzano, J A; Castillo Romero, J L; Padilla Romero, M J; Sánchez Laínez, J J; Castillo Aguilar, C; Cegarra Navarro, M F

    2007-01-01

    The incidence of tuberculosis has lately increased in developed countries. The most frequent affectation is the pulmonar one and in the ORL area the laryngeal. The lingual affectation is exceptional. We present a case of a man 39 years old, with bilateral pulmonar, left vocal cord and mobile tongue affectation, negative Mantoux, positive spit culture and presence of acido-alcohol resistent bacillus in lingual and laryngeal biopsies. After antituberculosis treatment during 6 months the laryngeal and lingual lesions disappeared. We have only found two cases published of simultaneous tuberculosis in these three localisations in the last 30 years.

  2. [Tumoral microembolism and cor-pulmonar as manifestation of hepatocelular carcinoma].

    PubMed

    Canelo Aybar, Carlos Gilberto; Cuadra Urteaga, José Luís; Fujii, F; Romaní Romaní, Franco; Atencia Matute, Fernando Alonso; Verona Rubio, Rogger Oscar

    2008-01-01

    The tumour pulmonary micro-embolism is a rare condition characterized by the occlusion of pulmonary small arteries, arteriolas, and alveolar capillaries septales, accompanied of trombosis. Occasionally the development of pulmonary hypertension is the first manifestation of an occult neoplasia, in series of autopsies, an incidence from 3 to 26% has been reported in solid tumors, being clinical evident in 8%. Few cases have documented the development of this condition in patients with carcinoma hepatocelular, we report the case of a 16-year-old male who comes to the emergency with signs of cardiac insufficiency and cor pulmonare whose anatomopatological study confirmed a tumour massive microembolic compromise at pulmonary level and hepatocarcinoma.

  3. Os trigonum syndrome.

    PubMed

    Nault, Marie-Lyne; Kocher, Mininder S; Micheli, Lyle J

    2014-09-01

    Os trigonum syndrome is the result of an overuse injury of the posterior ankle caused by repetitive plantar flexion stress. It is predominantly seen in ballet dancers and soccer players and is primarily a clinical diagnosis of exacerbated posterior ankle pain while dancing on pointe or demi-pointe or while doing push-off maneuvers. Symptoms may improve with rest or activity modification. Imaging studies, including a lateral radiographic view of the ankle in maximal plantar flexion, will typically reveal the os trigonum between the posterior tibial lip and calcaneus. If an os trigonum is absent on radiography, an MRI may reveal scar tissue behind the posterior talus, a condition associated with similar symptoms. Os trigonum syndrome is often associated with pathology of the flexor hallucis longus tendon. Treatment begins with nonsurgical measures. In addition to physical therapy, symptomatic athletes may need surgical excision of os trigonum secondary to unavoidable plantar flexion associated with their sport. This surgery can be performed using open or arthroscopic approaches.

  4. [Pulmonary involvement in systemic sclerosis. Alveolitis, fibrosis and pulmonar arterial hypertension].

    PubMed

    Navarro, Carmen

    2006-11-01

    Pulmonary involvement in systemic sclerosis. Alveolitis, fibrosis and pulmonar arterial hypertension Lung disease is present in most of the patients with systemic sclerosis and is now the most important cause of mortality. Interstitial lung disease and pulmonary hypertension are, so far, the main disorders found and both are difficult to detect at the earliest stages. However, diagnostic tools such as immunological test, lung function test, high resolution CT, bronchoalveolar lavage, echocardiography, right-side cardiac catheterization, or lung biopsy are necessary to accurately evaluate the clinical status and allow to improve the management organ-specific ad hoc. Progress in immunological and vascular therapies as well as other emergence drugs offer new expectations to scleroderma patients.

  5. Symptomatic Os Infranaviculare

    PubMed Central

    Roh, Kwon Jae

    2013-01-01

    The author observed a new accessory bone of the foot in the distal portion of navicular, which articulated with the medial cuneiform and the intermediate cuneiform, and named it os infranaviculare. A degenerative change was observed between the accessory bone and the navicular; this caused midfoot pain to the patient during weight-bearing. Thus, the patient was treated by excision of the accessory bone. The symptom was relieved at one-year postoperative. PMID:23730481

  6. Os Odontoideum: Rare Cervical Lesion

    DTIC Science & Technology

    2011-11-01

    the articulation between C1 and the os odontoideum on flexion imaging. The remainder of his cervical vertebral bodies had normal alignment with no...appears normal. Figure 3. Flexion view of plain cervical spine. This image shows abnormal translation of the articulation between C1 and the C2 os...worldwide. Peer Reviewed Title: Os Odontoideum: Rare Cervical Lesion Journal Issue: Western Journal of Emergency Medicine, 12(4) Author: Robson

  7. 187Os/186Os in Lunar and Meteoritic Materials

    NASA Astrophysics Data System (ADS)

    Birck, J. L.; Allegre, C. J.

    1993-07-01

    The unique potentiallity of the ^187Re-^1870s radiochronometer stems from the chemical properties of the 2 elements. Their siderophilic nature has made the dating of the metal phase of iron meteorites and chondrites possible [1,2]. In silicate crystallization or melting, Os behaves as a strongly compatible element [3]. For Re the results hereunder show that its behavior is highly variable, depending on context. The development of the highly sensitive negative thermal ionization mass spectrometry [4,5] made possible the extensive analysis of silicate materials. We developed a chemical separation method allowing the analysis of 0,5 g of silicate with an Os blank of 0.3 pg (1pg=10^-12 g). The isotopic measurement of Os has a typical precision of a few permil for 1 pg of Os. A variety of samples has been investigated. Iron Meteorites: The main purpose of this study was to shed some light on the history of Kodaikanal. The silicate inclusions of this meteorite were reset at 3.7 Ga for both the Rb-Sr and the U-Pb chronometers [6,7]. The data from Coahuila, Canyon Diablo, Tlacotepec, and North Chile plot within 1% on the same isochron along with 3 samples from 2 locations inside the meteorite of Kodaikanal. As a consequence the Kodaikanal parent body did not form at 3.7 Ga but at about the same time as the parent bodies of the the majority of the other iron meteorites (~4.5 Ga). The only difference is that Kodaikanal suffered a strong secondary event at 3.7 Ga, which reset Rb/Sr and U-Pb chronometers but did not fractionate the Re/Os ratio. This result has already been suggested by our earlier work [8]. The St Severin Chondrite: A bulk sample and several batches of the metal separated from this chondrite were analysed. They plot on the iron meteorite isochron. However this metal is heterogeneous in Re/Os by a factor of at least 2 and indicates an uncomplete homogeinization of Re/Os between metal grains during parent body metamorphism. Basaltic Materials: Basaltic

  8. Mac OS X for Astronomy

    NASA Astrophysics Data System (ADS)

    Pierfederici, F.; Pirzkal, N.; Hook, R. N.

    Mac OS X is the new Unix based version of the Macintosh operating system. It combines a high performance DisplayPDF user interface with a standard BSD UNIX subsystem and provides users with simultaneous access to a broad range of applications which were not previously available on a single system such as Microsoft Office and Adobe Photoshop, as well as legacy X11-based scientific tools and packages like IRAF, SuperMongo, MIDAS, etc. The combination of a modern GUI layered on top of a familiar UNIX environment paves the way for new, more flexible and powerful astronomical tools to be developed while assuring compatibility with already existing, older programs. In this paper, we outline the strengths of the Mac OS X platform in a scientific environment, astronomy in particular, and point to the numerous astronomical software packages available for this platform; most notably the Scisoft collection which we have compiled.

  9. 187Os-186Os and He Isotope Systematics of Iceland Picrites

    NASA Astrophysics Data System (ADS)

    Brandon, A. D.; Brandon, A. D.; Graham, D.; Gautason, B.

    2001-12-01

    Iceland is one of the longest-lived modern plumes, and seismic imaging supports a model where the roots of this plume are at the base of the lower mantle. Hence, Os isotopic data for lavas from this plume are ideal for further testing the role of core-mantle chemical exchange at the site of plume generation in the lower mantle, and for addressing the origin of Os-He isotopic variation in plumes. Recent work has shown that lavas from some plume systems (Hawaii, Noril'sk-Siberia, Gorgona) show coupled enrichments in 186Os/188Os and 187Os/188Os, not observed in upper mantle materials including abyssal peridotites. Picrites from Hawaii display a positive correlation between 186Os/188Os and He isotopes (R/Ra), where range in 186Os/188Os of 0.119834+/-28 to 0.1198475+/-29 and corresponding R/Ra from +7 to +25. These systematics are consistent with a lower mantle source for the radiogenic 186Os signal in the Hawaiian plume. The coupled Os enrichments in these plumes has been attributed to core-mantle chemical exchange, consistent with generation of the Hawaiian plume at the base of the lower mantle in D". Other potentially viable models await additional scrutiny. New He isotope and high precision 186Os/188Os and 187Os/188Os measurements for Iceland picrites show unique systematics compared to Hawaii. These picrites have 187Os/188Os ranging from 0.1297 to 0.1381 and R/Ra of +9 to +18, with generally higher R/Ra correlating with higher 187Os/188Os. Unlike the Hawaiian picrites from Hualalai and Loihi, which have coupled enrichments in 186Os/188Os and 187Os/188Os, the Iceland picrites show no enrichment 186Os/188Os - 0.1198363+/-28 (2s, n=14). Such Os-He isotopic variations require one end-member source that has high R/Ra, coupled with a long term elevated Re/Os and Pt/Os similar to that of the upper mantle. These systematics are inconsistent with either known upper mantle materials or those purported for ancient recycled slabs and may be a previously unidentified component

  10. Neutron capture cross sections of {sup 186}Os, {sup 187}Os, and {sup 189}Os for the Re-Os chronology

    SciTech Connect

    Segawa, M.; Masaki, T.; Nagai, Y.; Temma, Y.; Shima, T.; Mishima, K.; Igashira, M.; Goriely, S.; Koning, A.; Hilaire, S.

    2007-08-15

    Discrete as well as continuum {gamma}-ray energy spectra from the neutron capture by {sup 186}Os, {sup 187}Os, and {sup 189}Os have been taken for the first time at 5{<=}E{sub n}{<=}90 keV by an anti-Compton NaI(Tl) spectrometer. The detection of a weak discrete {gamma}-ray, about 0.5% of total {gamma}-ray strength, demonstrates the high sensitivity of the present measurement. The energy spectra enabled us to accurately determine the reaction cross sections with a small systematic uncertainty. Based on the new cross sections, we reestimate on the basis of a careful reaction cross section calculation the correction factor F{sub {sigma}} for the neutron capture on the 9.75-keV first excited state in {sup 187}Os as a function of stellar temperature, as required to derive the age of the galaxy within the Re-Os chronology.

  11. Osmium uptake, distribution, and 187Os/188Os and 187Re/188Os compositions in Phaeophyceae macroalgae, Fucus vesiculosus: Implications for determining the 187Os/188Os composition of seawater

    NASA Astrophysics Data System (ADS)

    Racionero-Gómez, B.; Sproson, A. D.; Selby, D.; Gannoun, A.; Gröcke, D. R.; Greenwell, H. C.; Burton, K. W.

    2017-02-01

    The osmium isotopic composition (187Os/188Os) of seawater reflects the balance of input from mantle-, continental- and anthropogenic-derived sources. This study utilizes the Phaeophyceae, Fucus vesiculosus, to analyse its Os abundance and uptake, as well as to assess if macroalgae records the Os isotope composition of the seawater in which it lives. The data demonstrates that Os is not located in one specific biological structure within macroalgae, but is found throughout the organism. Osmium uptake was measured by culturing F. vesiculosus non-fertile tips with different concentrations of Os with a known 187Os/188Os composition (∼0.16), which is significantly different from the background isotopic composition of local seawater (∼0.94). The Os abundance of cultured non-fertile tips show a positive correlation to the concentration of the Os doped seawater. Moreover, the 187Os/188Os composition of the seaweed equalled that of the culture medium, strongly confirming the possible use of macroalgae as a biological proxy for the Os isotopic composition of the seawater.

  12. Neutron capture and inelastic scattering cross sections for {sup 186}Os, {sup 187}Os, and {sup 189}Os and the Re-Os chronology

    SciTech Connect

    Segawa, M.; Nagai, Y.; Masaki, T.; Temma, Y.; Shima, T.; Mishima, K.; Igashira, M.; Goriely, S.; Koning, A.; Hilaire, S.

    2008-05-21

    We measured the neutron capture cross sections of {sup 186,187,189}Os taking for the first time their pulse height spectra for neutrons between 5 and 90 keV by means of an anti-Compton NaI(Tl) spectrometer. The neutron inelastic scattering cross section for {sup 187}Os as well as the neutron elastic scattering cross sections for {sup 186,187}Os were also observed with use of {sup 6}Li-glass scintillation detectors with a small systematic uncertainty.

  13. Painful os acromiale presenting as septic shoulder.

    PubMed

    Kapadia, Nirav S; Demetracopoulos, Constantine A; Fayad, Laura M; McFarland, Edward G; Millin, Michael G

    2011-10-01

    The unfused acromial apophysis of an os acromiale typically is an undetected orthopedic anomaly with minimal symptoms. In some instances, however, pain and disability can result from motion between the unfused bone fragments. Trauma to the acromion can similarly displace the unfused os acromiale or can result in chronic symptoms of pain and swelling. In this article, we report the case of a young man who had a fractured os acromiale secondary to trauma and presented with the signs and symptoms of a septic glenohumeral joint.

  14. Functions of OsDof25 in regulation of OsC4PPDK.

    PubMed

    Zhang, Y; Verhoeff, N I; Chen, Z; Chen, S; Wang, Mei; Zhu, Zhen; Ouwerkerk, P B F

    2015-10-01

    Relative little is known about the functions of the so-called Dof zinc factors in plants. Here we report on the analysis of OsDof25 and show a function in regulation of the important C4 photosynthesis gene, OsC4PPDK in rice. Over-expression of OsDof25 enhanced the expression of OsC4PPDK in transient expression experiments by binding in a specific way to a conserved Dof binding site which was confirmed by yeast and in vitro binding studies. Expression studies using promoter GUS plants as well as qPCR experiments showed that OsDof25 expressed in different tissues including both photosynthetic and non-photosynthetic organs and that expression of OsDof25 was partially overlapping with the OsC4PPDK gene. Conclusive evidence for a role of OsDof25 in regulation of C4PPDK came from loss-of-function and gain-of-function experiments with transgenic rice, which showed that down-regulation or over-expression of OsDof25 correlated with OsC4PPDK expression and that OsDof25 has functions as transcriptional activator.

  15. Tracking the Hirnantian glaciation using Os isotopes

    NASA Astrophysics Data System (ADS)

    Finlay, Alexander J.; Selby, David; Gröcke, Darren R.

    2010-05-01

    Here we present initial 187Os/188Os (Osi) values integrated with δ13Corg for the first Paleozoic section - the Ordovician/Silurian boundary GSSP at Dob's Linn, Scotland. Our 187Os/188Os data tracks major changes in climate that occurred during the Late Ordovician (Hirnantian glaciation), which coincides with the second largest known mass extinction. During the complanatus and early anceps Biozones Osi values increase from 0.28-1.08. This provides evidence for a period of increased silicate weathering of radiogenic continental crust, likely from the Caledonian Orogen. This increase in weathering was likely the driving mechanism for the drawdown in atmospheric CO2 and global cooling that resulted in the onset of the Hirnantian Glaciation. A decrease to less radiogenic Osi occurs at the base Hirnantian extraordinarius Biozone and coincides with the trend to more positive δ13Corg values that mark the onset of the Hirnantian Glaciation. The trend in Osi during this interval is ascribed to Hirnantian ice cover and reduced chemical weathering rates cutting the supply of radiogenic material to the Iapetus Ocean. The reduction in silicate weathering enabled atmospheric CO2 to return back to greenhouse levels, causing rapid deglaciation during the mid persculptus Biozone. This period is marked by an abrupt increase in Osi values from 0.6 to 1.08 over 19 cm of stratigraphy and coincides with the deglacial limb of the δ13Corg profile. We interpret the Osi data to reflect the leaching of exposed radiogenic 187Os/188Os bearing glacial deposits and increased weathering of radiogenic 187Os/188Os silicate terrane during the deglaciation. Previous workers have identified the Hirnantian glaciation primarily through δ13C stratigraphy. However, our Os isotope data indicate that an initial mechanism (i.e. increased silicate weathering) was the driving mechanism behind the Hirnantian Glaciation and subsequent mass extinction. Thus, by coupling Osi and δ13Corg proxies we provide the

  16. Intraosseous tophus deposits in the os trigonum.

    PubMed

    Ercin, Ersin; Gamsizkan, Mehmet; Avsar, Serdar

    2012-01-16

    High levels of uric acid cause accumulation of monosodium urate crystals. This formation of masses is called tophus. Intraosseous tophus deposits are rare, even for patients with gout. We report an unusual case of intraosseous tophus deposits in the os trigonum. The patient presented with ankle pain with no previous history of gout. On examination, tenderness on the posterior aspect of his ankle and limitation of plantarflexion was noted. Laboratory values were normal, except for an elevated serum uric acid value. Radiographs of the right ankle showed the presence of a large os trigonum with osteosclerotic changes, whereas magnetic resonance imaging showed intraosseous tophus deposits in the os trigonum. Conservative therapy failed, and the patient was admitted for an endoscopic resection of the os trigonum.Intraosseous chalky crystals were detected during endoscopic resection of the os trigonum. The histological diagnosis was tophaceous gout. The underlying pathological mechanism of intraosseous tophi is uncertain. Penetration of urate crystals from the joint due to hyperuricemia may be the mechanism of deposition in this patient.When a patient with hyperuricemia presents with posterior ankle impingement symptoms, intraosseous tophus deposits should be included in the differential diagnosis. Posterior endoscopic excision may be an option for treating intraosseous lesions of the os trigonum because of good visualization, satisfactory excision, and rapid recovery time.

  17. The causes for geographical variations in OS187/OS186 at the Cretaceous-Tertiary boundary

    NASA Technical Reports Server (NTRS)

    Turekian, K. K.; Esser, B. K.; Ravizza, G. E.

    1988-01-01

    Researchers at Yale has approached the problem of the osmium isotopic composition of marine deposits formed in contact with both oxidized and reduced bottom waters. The measured (187) Os/(186) Os ratios of modern bulk sediment can be explained using mixing equations involving continental detrital, volcaniclastic, cosmogenic and hydrogeneous components. These studies show that sediments deposited under reducing marine conditions contain a hydrogenous component which is enriched in Re and has a radiogenic (187) Os/(186) Os ratio. The presence of such a hydrogenous component in the marine fish clay at Stevns Klint can account for the elevation of its (187) Os/(186) Os ration above the expected meteoritic value. Mass balance considerations require the Re/Os ratio of the phase precipitated from the terminal Cretaceous sea at Stevns Klint to have been about one tenth the value observed in contemporary deposits in the Black Sea, assuming Re has not been lost (or Os gained) subsequent to precipitation. In continental sections, the elevation of the (187) Os/(186) Os ratio in boundary layers may be due to precipitation from continental waters of crustally-derived radiogenic osmium either contemporaneous with the meteoritic (or mantle) osmium deposition or later during diagenesis.

  18. Bilateral Symptomatic Os Epilunatum: A Case Report

    PubMed Central

    Mauler, Flavien; Rahm, Stefan; Schweizer, Andreas; Nagy, Ladislav

    2015-01-01

    Background Accessory carpal ossicles may be the cause of atraumatic wrist pain or may be misinterpreted as a fracture after a trauma. Case Description We report the case of a patient suffering with chronic, bilateral wrist pain without history of trauma. Sonographic examination showed a bilateral symptomatic os epilunatum, both of which were surgically resected, resulting in pain relief. Literature Review Os epilunatum is a rare entity that has been reported only in few cadaveric specimen. Clinical Relevance Os epilunatum is a rare accessory ossicle of the carpus that can cause this aggravating pain. Sonography enabled accurate diagnosis of this anomaly. Because of possible associated tear of the scapholunate ligament, we recommend intraoperative testing of the stability of the scapholunate joint. PMID:25709883

  19. TENDENCIA DE LA TUBERCULOSIS EN LA REGIÓN SANITARIA V DE LA PROVINCIA DE BUENOS AIRES, AÑOS 2000–2011

    PubMed Central

    CHIRICO, CRISTINA; SANJURJO, MYRIAM; IRIBARREN, SARAH; APPENDINO, ANDREA; ZERBINI, ELSA; ETCHEVARRIA, MIRTA

    2016-01-01

    El objetivo del presente trabajo fue analizar la situación epidemiológica de la tuberculosis (TB) en la Región Sanitaria V (RSV), provincia de Buenos Aires. El estudio de tendencia permitió conocer un valor promedio de las variaciones de la tasa de incidencia (TI), calculadas por regresión lineal simple y expresadas como variación anual promedio (VAP). Se analizaron el número de casos notificados y TI por 100 000 habitantes de todas las formas de TB, los casos de TB pulmonar (TBP) y TBP confirmados por bacteriología, total casos por grupos de edad: 0 – 14; 15 – 29 y mayores de 64 años, entre el 1° de enero de 2000 al 31 de diciembre de 2011. La declinación de la TI fue menor al 5% para todas las formas de TB e inferior en las TBP confirmadas bacteriológicamente. Los casos de TBP y TI más elevadas, se concentraron en el grupo de 15 a 29 años, con tendencia estable o ligeramente ascendente de la TI en la TBP bacilífera. El mismo comportamiento presentaron los casos de TBP infantil con confirmación bacteriológica. La mayor velocidad de descenso en la TI de la TBP se produjo en este grupo de edad, mientras que en mayores de 64 años, el descenso fue sostenido en el tiempo. La TB persiste como un riesgo de salud en la RSV, con casos en edades jóvenes, por lo que sigue siendo necesario fortalecer el control de la TB en esta región. PMID:26117604

  20. Os isotopic composition of steels: Constraints on sources of Os in steel & crustal isotopic evolution of iron ores

    NASA Astrophysics Data System (ADS)

    Chatterjee, R. N.; Lassiter, J. C.

    2013-12-01

    Metal contamination during sample processing is a potential concern in Os-isotope studies. We examined Os concentrations and Os isotopes in industrial steels. Samples include high Cr stainless steels (>10.5% Cr), low alloy steels (>=92% Fe) and high alloy steels (<92% Fe). The chief components used to make steel are iron ore, chromites and coke. Coke is derived from coals that have low Os concentration (~36 ppt) [1]. Chromites in steels are mined from chromitites, which have high average Os concentrations and mantle-like 187Os/188Os ratios (~88 ppb Os, 187Os/188Os ≈ 0.127×24) [2]. Iron ores used in US steel manufacturing derive chiefly from magnetites mined from iron-bearing formations such as Banded Iron Formations (BIF), which have median Os concentration of ~4.8 ppb and radiogenic 187Os/188Os ≈ 0.358×388 [3]. Os concentrations in the measured steels span a wide range, from 0.03 to 22 ppb. The 187Os/188Os ratios vary from 0.144-4.12. Such high Os concentrations and radiogenic isotopic compositions confirm that metal contamination can affect Os-isotope compositions during sample processing, particularly for low-[Os] samples. There is no correlation between C and Os concentration in steel, indicating that coke is not a major Os source in steels. Os concentrations in steels are positively correlated with Cr content, suggesting that chromite-derived Os dominates the Os budget in stainless steels. 187Os/188Os is negatively correlated with Cr content, ranging from 0.144-0.195 in high-Cr (>10.5 % Cr) steels but from 0.279-4.12 in low-Cr steels. In addition, there is a positive correlation between 1/Os and 187Os/188Os, consistent with two-component mixing of Os derived from magnetite ore and chromites. Lower Os concentrations in steels than expected from simple mixing of magnetite and chromitite suggest some volatile Os loss during smelting. Although the current data is limited, the 186Os-187Os trend defined by the steel analyses can be utilized to extrapolate

  1. 186Os/188Os Isotopic Compositions of Peridotites: Constraints on Melt Depletion and Pt/Os Evolution of the Upper Mantle

    NASA Astrophysics Data System (ADS)

    Chatterjee, R. N.; Lassiter, J. C.

    2014-12-01

    Global correlations between Al2O3 and Pt/Os in mantle peridotites suggest that Pt behaves incompatibly relative to Os during partial melting [c.f., 1]. Because 190Pt decays to 186Os (t1/2 = 468 Ga), correlations between 186Os/188Os and peridotite fertility can be used to constrain the long-term Pt/Os evolution of the depleted mantle and the initial Pt/Os ratio of the primitive upper mantle (PUM). We examined 186Os/188Os in mantle peridotites from continental (Rio Grande Rift/Colorado Plateau) and oceanic (Lena Trough, Hawaiian Islands) settings that span a wide range in fertility (Al2O3 ~0.67-4.42 %) and 187Os/188Os ratios (0.1138-0.1305). The new data define a narrow range in 186Os/188Os (0.1198338 to 0.1198393, 2 SD~24 ppm), placing constraints on long-term Pt/Os variability in the DMM. 186Os/188Os is broadly correlated with indices of melt depletion including spinel Cr#, clinopyroxene Cr#, and clinopyroxene Yb content, consistent with the inferred relative compatibility of Pt and Os during partial melting. Extrapolation of the alumina-186Os/188Os trend to PUM alumina content (~4.5 wt% Al2O3; [2]) suggests a PUM 186Os/188Os of ~0.1198380±15, similar to the 186Os/188Os of H chondrites (~0.1198398±16; [3]). This 186Os/188Os value is consistent with a PUM Pt/Os of 1.8±0.3, similar to Pt/Os values measured in several classes of chondrites (Carbonaceous ~1.9±0.2, Ordinary ~2.0±0.3 and Enstatite ~1.9±0.2; [3]). Whereas ~84% of peridotites worldwide [excluding low-[Os] samples (<1 ppb Os) that may have been compromised by melt-rock reaction and/or weathering and alteration] with measured Pt/Os ratios have Pt/Os between 0.3 and 3.1 (the range permissible from 186Os/188Os variations for melt extraction from PUM at ~1.5 Ga), only ~36% fall between 1.3 and 2.2 (a narrower range consistent with an older ~4.5 Ga melt depletion age). This suggests that much of the observed Pt/Os variability in mantle peridotites is relatively recent. Close agreement between our inferred

  2. Re-Os Isotope Systematics in Lunar Soils and Breccias

    NASA Technical Reports Server (NTRS)

    Chen, J. H.; Papanastassiou, D. A; Wasserburg, G. J.

    2002-01-01

    Lunar soil and breccia samples show a narrow range in 187Os/188Os, in the range for H-chondrites and unfractionated irons. All samples show enrichments in 187Re/188Os, possibly reflecting loss of Os, associated with the terminal lunar cataclysm. Additional information is contained in the original extended abstract.

  3. Re-Os isotope systematics in black shales from the Lesser Himalaya: their chronology and role in the 187Os/ 188Os evolution of seawater

    NASA Astrophysics Data System (ADS)

    Singh, Sunil K.; Trivedi, J. R.; Krishnaswami, S.

    1999-08-01

    Re and Os abundances and Os isotope systematics have been measured in a number of black shales sampled from outcrops and two underground phosphorite mines, Maldeota and Durmala, in the Lesser Himalaya. The Re and Os concentrations in these samples exhibit wide range, 0.2 to 264 ng/g and 0.02 to 13.5 ng/g, respectively, with a mean Re/Os of ˜25. The 187Os/ 188Os of these samples also show a broad range 1.02 to 11.6, with many of them far more radiogenic than the currently eroding continental crust. The black shales from the Maldeota and Durmala mines, collected a few meters above the Krol-Tal (Pc-C) boundary and occurring in the same stratigraphic horizon, yield 187Re- 187Os isochron ages of 554 ± 16 and 552 ± 22 Ma, respectively, consistent with fossil evidences and those assigned for the Pc-C boundary at various other locations. These results indicate closed system behaviour of Re and Os in these mine samples and reaffirm the validity of 187Re- 187Os pair to date organic-rich sediments. The age of these mine samples from the outer belt seems to be a few hundred millions of years younger than the preliminary Re-Os age of 839 ± 138 Ma for black shales from Theog, collected from the inner belt. These initial results lean toward the hypothesis that the inner belt sediments were deposited earlier than the outer belt; however, more analyses of black shales are needed to confirm this. The role of weathering black shales from the Himalaya in contributing to the Os isotope evolution of seawater over the past ˜25 Ma was assessed using a simple budget model for seawater Os and assuming values for Os fluxes and 187Os/ 188Os based on the available limited data on Os concentration and its 187Os/ 188Os in rivers and oceans. These calculations indicate that the required contributions from black shale weathering to account for the entire increase in oceanic 187Os/ 188Os over the past ˜16 Ma is difficult to satisfy by varying only the Os flux from HTP rivers ( 187Os/ 188Os

  4. Neutron capture studies on /sup 189/Os

    SciTech Connect

    Bruce, A.M.; Colvin, G.G.; Gelletly, W.; Warner, D.D.

    1987-01-01

    An extensive study of the level structure of /sup 189/Os has been carried out using the (n,..gamma..) and (n,e-) reactions. The use of the Average Resonance Capture technique ensures that the complete set of 1/2-, 3/2- states has been established up to 1500 keV in excitation energy and secondary ..gamma..-rays have been measured in singles and coincidence to build up the detailed level scheme. 7 refs., 2 figs.

  5. Advanced Development of Certified OS Kernels

    DTIC Science & Technology

    2015-06-01

    and Coq Ltac libraries. 15. SUBJECT TERMS Certified Software; Certified OS Kernels; Certified Compilers; Abstraction Layers; Modularity; Deep ...module should only need to be done once (to show that it implements its deep functional specification [14]). Global properties should be derived from the...building certified abstraction layers with deep specifications. A certified layer is a new language-based module construct that consists of a triple pL1,M

  6. Space Shuttle Usage of z/OS

    NASA Technical Reports Server (NTRS)

    Green, Jan

    2009-01-01

    This viewgraph presentation gives a detailed description of the avionics associated with the Space Shuttle's data processing system and its usage of z/OS. The contents include: 1) Mission, Products, and Customers; 2) Facility Overview; 3) Shuttle Data Processing System; 4) Languages and Compilers; 5) Application Tools; 6) Shuttle Flight Software Simulator; 7) Software Development and Build Tools; and 8) Fun Facts and Acronyms.

  7. The Late Eocene 187Os / 188Os excursion: Chemostratigraphy, cosmic dust flux and the Early Oligocene glaciation

    NASA Astrophysics Data System (ADS)

    Dalai, Tarun K.; Ravizza, Gregory E.; Peucker-Ehrenbrink, B.

    2006-01-01

    High resolution records (ca. 100 kyr) of Os isotope composition ( 187Os / 188Os) in bulk sediments from two tropical Pacific sites (ODP Sites 1218 and 1219) capture the complete Late Eocene 187Os / 188Os excursion and confirm that the Late Eocene 187Os / 188Os minimum, earlier reported by Ravizza and Peucker-Ehrenbrink [Earth Planet. Sci. Lett. 210 (2003) 151-165], is a global feature. Using the astronomically tuned age models available for these sites, it is suggested that the Late Eocene 187Os / 188Os minimum can be placed at 34.5 ± 0.1 Ma in the marine records. In addition, two other distinct features of the 187Os / 188Os excursion that are correlatable among sections are proposed as chemostratigraphic markers which can serve as age control points with a precision of ca. ± 0.1 Myr. We propose a speculative hypothesis that higher cosmic dust flux in the Late Eocene may have contributed to global cooling and Early Oligocene glaciation (Oi-1) by supplying bio-essential trace elements to the oceans and thereby resulting in higher ocean productivity, enhanced burial of organic carbon and draw down of atmospheric CO 2. To determine if the hypothesis that enhanced cosmic dust flux in the Late Eocene was a cause for the 187Os / 188Os excursion can be tested by using the paired bulk sediment and leachate Os isotope composition; 187Os / 188Os were also measured in sediment leachates. Results of analyses of leachates are inconsistent between the south Atlantic and the Pacific sites, and therefore do not yield a robust test of this hypothesis. Comparison of 187Os / 188Os records with high resolution benthic foraminiferal δ18O records across the Eocene-Oligocene transition suggests that 187Os flux to the oceans decreased during cooling and ice growth leading to the Oi-1 glaciation, whereas subsequent decay of ice-sheets and deglacial weathering drove seawater 187Os / 188Os to higher values. Although the precise timing and magnitude of these changes in weathering fluxes

  8. Foreign body ingestion: rare cause of cervical abscess.

    PubMed

    Costa, Liliana; Larangeiro, João; Pinto Moura, Carla; Santos, Margarida

    2014-01-01

    IntroduçÉo: A ingestÉo de corpo estranho é um motivo frequente de recurso à urgência hospitalar. As complicações graves, embora raras, incluem perfuraçÉo faringo-esofágica, fistula aorto-esofágica e infecçÉo cervical profunda.Material e Métodos: Foram analisados, retrospectivamente, os casos de ingestÉo de corpo estranho com internamento num hospital terciário, entre 1989 e 2011. Seleccionaram-se os casos complicados por abcesso cervical profundo, descrevendo-se a semiótica, resultados de meios complementares de diagnóstico, terapêutica efectuada e evoluçÉo clínica.Resultados: Dos 1679 casos, 319 referentes a crianças e 1360 a adultos, reportam-se dois casos (0,12%): uma criança, 13 meses, com abcesso retrofaríngeo após ingestÉo de osso de frango e um adulto, 41 anos, com abcesso parafaríngeo após ingestÉo de espinha de peixe. As complicações manifestaram-se quatro e três dias após remoçÉo do corpo estranho, respectivamente. Em ambos foram efectuadas Tomografias Computorizadas cervicais com contraste e drenagem cirúrgica dos abcessos; a criança foi ainda submetida a esofagoscopia rígida para remoçÉo de corpo estranho residual e encerramento da perfuraçÉo esofágica associada.DiscussÉo: Os abcessos cervicais sÉo uma complicaçÉo possível da ingestÉo de corpo estranho e constituem um desafio diagnóstico, principalmente em idade pediátrica. A manipulaçÉo esofágica prévia por fibroscopia poderá ser considerada um factor de risco. A imagiologia (Tomografia Computorizada cervical com contraste ou Resson'ncia Magnética Cervical) foi essencial para o diagnóstico e o planeamento cirúrgico.ConclusÉo: Embora raros, perante a história recente de ingestÉo/remoçÉo de corpo estranho esofágico e a presença de sintomas compatíveis, os abcessos cervicais devem ser tidos em consideraçÉo, dado o potencial de morbilidade e mortalidade na ausência de uma abordagem terapêutica adequada.

  9. Re-Os geochronology and coupled Os-Sr isotope constraints on the Sturtian snowball Earth.

    PubMed

    Rooney, Alan D; Macdonald, Francis A; Strauss, Justin V; Dudás, Francis Ö; Hallmann, Christian; Selby, David

    2014-01-07

    After nearly a billion years with no evidence for glaciation, ice advanced to equatorial latitudes at least twice between 717 and 635 Mya. Although the initiation mechanism of these Neoproterozoic Snowball Earth events has remained a mystery, the broad synchronicity of rifting of the supercontinent Rodinia, the emplacement of large igneous provinces at low latitude, and the onset of the Sturtian glaciation has suggested a tectonic forcing. We present unique Re-Os geochronology and high-resolution Os and Sr isotope profiles bracketing Sturtian-age glacial deposits of the Rapitan Group in northwest Canada. Coupled with existing U-Pb dates, the postglacial Re-Os date of 662.4 ± 3.9 Mya represents direct geochronological constraints for both the onset and demise of a Cryogenian glaciation from the same continental margin and suggests a 55-My duration of the Sturtian glacial epoch. The Os and Sr isotope data allow us to assess the relative weathering input of old radiogenic crust and more juvenile, mantle-derived substrate. The preglacial isotopic signals are consistent with an enhanced contribution of juvenile material to the oceans and glacial initiation through enhanced global weatherability. In contrast, postglacial strata feature radiogenic Os and Sr isotope compositions indicative of extensive glacial scouring of the continents and intense silicate weathering in a post-Snowball Earth hothouse.

  10. Re-Os geochronology and coupled Os-Sr isotope constraints on the Sturtian snowball Earth

    PubMed Central

    Rooney, Alan D.; Macdonald, Francis A.; Strauss, Justin V.; Dudás, Francis Ö.; Hallmann, Christian; Selby, David

    2014-01-01

    After nearly a billion years with no evidence for glaciation, ice advanced to equatorial latitudes at least twice between 717 and 635 Mya. Although the initiation mechanism of these Neoproterozoic Snowball Earth events has remained a mystery, the broad synchronicity of rifting of the supercontinent Rodinia, the emplacement of large igneous provinces at low latitude, and the onset of the Sturtian glaciation has suggested a tectonic forcing. We present unique Re-Os geochronology and high-resolution Os and Sr isotope profiles bracketing Sturtian-age glacial deposits of the Rapitan Group in northwest Canada. Coupled with existing U-Pb dates, the postglacial Re-Os date of 662.4 ± 3.9 Mya represents direct geochronological constraints for both the onset and demise of a Cryogenian glaciation from the same continental margin and suggests a 55-My duration of the Sturtian glacial epoch. The Os and Sr isotope data allow us to assess the relative weathering input of old radiogenic crust and more juvenile, mantle-derived substrate. The preglacial isotopic signals are consistent with an enhanced contribution of juvenile material to the oceans and glacial initiation through enhanced global weatherability. In contrast, postglacial strata feature radiogenic Os and Sr isotope compositions indicative of extensive glacial scouring of the continents and intense silicate weathering in a post–Snowball Earth hothouse. PMID:24344274

  11. Cooperative application/OS DRAM fault recovery.

    SciTech Connect

    Ferreira, Kurt Brian; Bridges, Patrick G.; Heroux, Michael Allen; Hoemmen, Mark; Brightwell, Ronald Brian

    2012-05-01

    Exascale systems will present considerable fault-tolerance challenges to applications and system software. These systems are expected to suffer several hard and soft errors per day. Unfortunately, many fault-tolerance methods in use, such as rollback recovery, are unsuitable for many expected errors, for example DRAM failures. As a result, applications will need to address these resilience challenges to more effectively utilize future systems. In this paper, we describe work on a cross-layer application/OS framework to handle uncorrected memory errors. We illustrate the use of this framework through its integration with a new fault-tolerant iterative solver within the Trilinos library, and present initial convergence results.

  12. The auxin response factor, OsARF19, controls rice leaf angles through positively regulating OsGH3-5 and OsBRI1.

    PubMed

    Zhang, SaiNa; Wang, SuiKang; Xu, YanXia; Yu, ChenLiang; Shen, ChenJia; Qian, Qian; Geisler, Markus; Jiang, De An; Qi, YanHua

    2015-04-01

    Auxin and brassinosteroid (BR) are important phytohormones for controlling lamina inclination implicated in plant architecture and grain yield. But the molecular mechanism of auxin and BR crosstalk for regulating lamina inclination remains unknown. Auxin response factors (ARFs) control various aspects of plant growth and development. We here report that OsARF19-overexpression rice lines show an enlarged lamina inclination due to increase of its adaxial cell division. OsARF19 is expressed in various organs including lamina joint and strongly induced by auxin and BR. Chromatin immunoprecipitation (ChIP) and yeast one-hybrid assays demonstrate that OsARF19 binds to the promoter of OsGH3-5 and brassinosteroid insensitive 1 (OsBRI1) directing their expression. OsGH3-5-overexpression lines show a similar phenotype as OsARF19-O1. Free auxin contents in the lamina joint of OsGH3-5-O1 or OsARF19-O1 are reduced. OsGH3-5 is localized at the endoplasmic retieulum (ER) matching reduction of the free auxin contents in OsGH3-5-O1. osarf19-TDNA and osgh3-5-Tos17 mutants without erected leaves show a function redundancy with other members of their gene family. OsARF19-overexpression lines are sensitive to exogenous BR treatment and alter the expressions of genes related to BR signalling. These findings provide novel insights into auxin and BR signalling, and might have significant implications for improving plant architecture of monocot crops.

  13. Os-187/Os-188 and Highly Siderophile Element Systematics of Apollo 17 Aphanitic Melt Rocks

    NASA Technical Reports Server (NTRS)

    Puchtel, I. S.; Walker, R. J.; James, O. B.

    2005-01-01

    Introduction: Generally chondritic relative abundances and high absolute abundances of the highly siderophile elements (HSE: Ru, Rh, Pd, Re, Os, Ir, Pt, Au) in Earth s upper mantle provide strong evidence that these elements were added to the Earth following the last major interaction between its metallic core and silicate fraction. So called "late accretion" may have added materials comprising as much as 0.8% of the total mass of the Earth and possibly a similar proportion of mass to the Moon. We have begun to study the chemical nature of late accreted materials to the Earth - Moon system by examining the HSE contained in lunar impact-melt rocks. The HSE contained in melt rocks were largely added to the Moon during the period of time from the origin of the lunar highlands crust (4.4- 4.5 Ga) to the end of the late bombardment period (ca. 3.9 Ga). These materials provide the only direct chemical link to the late accretionary period. The chemical fingerprints of the HSE in late accreted materials may enable us to ascertain under what conditions and where in the solar system the late accreted materials formed. The Os-187/Os-188 ratios (reflecting long-term Re/Os), coupled with ratios of other HSE, can be diagnostic for identifying the nature of the impactor. A critical issue, however, will be deconvolving the exogenous from indigenous components.

  14. Re-Os dating of 3AB iron meteorites

    NASA Technical Reports Server (NTRS)

    Esat, Tezer M.; Bennett, Victoria

    1993-01-01

    Recently, Creaser et al., and Volkening and Heumann, have demonstrated the efficient production of large (approximately 10 exp -11 A) ion beams by negative thermal ionization mass spectrometry (NTIMS) using standard laboratory solutions of Os compounds. Horan et al., have applied NTIMS to a group of 7 IIA iron meteorites and obtained a Re-Os closure age of 4596 +/- 152 million years. The initial Os-187/Os-186 ratio was 0.8007 plus or minus 0.0029. In addition they analyzed 3 IIIA meteorite samples which indicated an age of 4554 +/- 180 million years and Os initial of 0.8120 +/- 0.0075 which does not overlap with the initial for the IIA irons. We have been independently pursuing a similar program with the direct aim of determining possible variations in the initial (Os-187)/(Os-186) ratio or Re-Os closure age of different classes of iron meteorite. We have applied NTIMS to Os extracted from the most common group of iron meteorites the IIIAB. These meteorites are believed to be of magmatic origin, formed by fractional crystallization of molten cores of asteroidal bodies. The present results point to a significantly lower initial (Os-187)/(Os-186) ratio of 0.7731 plus or minus 0.0050 than previously determined.

  15. Precise ReOs determinations and systematics of iron meteorites

    NASA Astrophysics Data System (ADS)

    Shen, J. J.; Papanastassiou, D. A.; Wasserburg, G. J.

    1996-08-01

    The ReOs system for samples of FeNi, sulphide, and phosphide from iron meteorites was investigated. Techniques were developed which yield reproducible analyses for Re/Os at the 2%‰ level and which permit complete isotopic exchange between sample and tracer, as is necessary for concentration measurements of Re and Os by isotope dilution. High precision osmium and rhenium isotope data have been obtained using negative ion thermal ionization, with ionization efficiencies of up to 10% for Os and 20% for Re, both for normals and for Re and Os extracted from the samples. Replicate analyses of Re/Os are in good agreement, within ±2.5%o. The results show a well defined correlation line on a 187Re- 187Os evolution diagram for iron meteorites from groups IAB, IIAB, IIIAB, IVA, and IVB, all taken together. This correlation line yields a slope of 0.07863 ± 0.00031 (2σ) and initial 187Os/ 188Os = 0.09560 ± 0.00018 (2σ). If the individual groups of iron meteorites for which there is sufficient dispersion in Re/Os are considered, data on the IIAB and on the IVA irons appear to indicate a difference in age of 60 ± 45 Ma, with the IVA group being older. This age difference is qualitatively the same as obtained for PdAg data but is larger. Sulphides from two IAB iron meteorites show extremely low concentrations of Re and Os and indicate that Re and Os are not partitioned into this phase during planetary differentiation. There is evidence for recent element remobilization or contamination, corresponding to relative enrichment of Re or loss of Os in the sulphides. Schreibersites contain small but significant amounts of Re and Os, with high Re/Os relative to the metal phases and with 187Os/ 188Os much more radiogenic than in the metal. Model ages for the Schreibersites are relatively young (4.3-3.5 AE) and indicate that the Schreibersites were open-systems for ReOs at least 0.5-1 AE after the original formation of the iron meteorites. It now appears possible to use

  16. iOS and OS X Apps for Exploring Earthquake Activity

    NASA Astrophysics Data System (ADS)

    Ammon, C. J.

    2015-12-01

    The U.S. Geological Survey and many other agencies rapidly provide information following earthquakes. This timely information garners great public interest and provides a rich opportunity to engage students in discussion and analysis of earthquakes and tectonics. In this presentation I will describe a suite of iOS and Mac OS X apps that I use for teaching and that Penn State employs in outreach efforts in a small museum run by the College of Earth and Mineral Sciences. The iOS apps include a simple, global overview of earthquake activity, epicentral, designed for a quick review or event lookup. A more full-featured iPad app, epicentral-plus, includes a simple global overview along with views that allow a more detailed exploration of geographic regions of interest. In addition, epicentral-plus allows the user to monitor ground motions using seismic channel lists compatible with the IRIS web services. Some limited seismogram processing features are included to allow focus on appropriate signal bandwidths. A companion web site, which includes background material on earthquakes, and a blog that includes sample images and channel lists appropriate for monitoring earthquakes in regions of recent earthquake activity can be accessed through the a third panel in the app. I use epicentral-plus at the beginning of each earthquake seismology class to review recent earthquake activity and to stimulate students to formulate and to ask questions that lead to discussions of earthquake and tectonic processes. Less interactive OS X versions of the apps are used to display a global map of earthquake activity and seismograms in near real time in a small museum on the ground floor of the building hosting Penn State's Geoscience Department.

  17. Radiographic characterization of the os penis in the cat.

    PubMed

    Piola, Valentina; Posch, Barbara; Aghte, Petra; Caine, Abby; Herrtage, Michael E

    2011-01-01

    The os penis in the cat has not been described radiographically, as compared with the dog. However, a small linear bony radiopacity is sometimes detected in the perineal area of male cats. We hypothesized that the feline os penis might be visible on survey radiographs of the pelvis, and we aimed to investigate the frequency of its visualization using analog and computed radiography (CR) system. One hundred radiographs of the pelvis of 99 male cats were reviewed retrospectively (50 were obtained with a CR system and 50 with an analog system). Age, breed, neutering status, and reason for presentation were recorded, as well as the visualization of the os penis. An os penis was detected in 19/50 (38%) cats with CR and in eight of 50 (16%) cats with analog radiography; this difference was statistically significant. With CR, the median age of cats with a visible os penis was significantly higher than in cats where the os penis was not seen. In one cat with a visible os penis examined with CR and analog radiography, the os penis was only visible on CR images. The penile tissues were examined histopathologically in one cat and well-differentiated bone was found but there were no pathologic findings detected in surrounding tissues. Thus, the os penis can be detected on radiographs of cats and this should not be mistaken for a pathologic finding such as urolithiasis or dystrophic mineralization.

  18. 186Os-187Os and highly siderophile element abundance systematics of the mantle revealed by abyssal peridotites and Os-rich alloys

    NASA Astrophysics Data System (ADS)

    Day, James M. D.; Walker, Richard J.; Warren, Jessica M.

    2017-03-01

    Abyssal peridotites are oceanic mantle fragments that were recently processed through ridges and represent residues of both modern and ancient melting. To constrain the nature and timing of melt depletion processes, and the composition of the mantle, we report high-precision Os isotope data for abyssal peridotites from three ocean basins, as well as for Os-rich alloys, primarily from Mesozoic ophiolites. These data are complemented by whole-rock highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re), trace- and major-element abundances for the abyssal peridotites, which are from the Southwest Indian (SWIR), Central Indian (CIR), Mid-Atlantic (MAR) and Gakkel Ridges. The results reveal a limited role for melt refertilization or secondary alteration processes in modifying abyssal peridotite HSE compositions. The abyssal peridotites examined have experienced variable melt depletion (2% to >16%), which occurred >0.5 Ga ago for some samples. Abyssal peridotites typically exhibit low Pd/Ir and, combined with high-degrees of estimated total melt extraction, imply that they were relatively refractory residues prior to incorporation into their present ridge setting. Recent partial melting processes and mid-ocean ridge basalt (MORB) generation therefore played a limited role in the chemical evolution of their precursor mantle domains. The results confirm that many abyssal peridotites are not simple residues of recent MORB source melting, having a more complex and long-lived depletion history. Peridotites from the Gakkel Ridge, SWIR, CIR and MAR indicate that the depleted MORB mantle has 186Os/188Os of 0.1198356 ± 21 (2SD). The Phanerozoic Os-rich alloys yield an average 186Os/188Os within uncertainty of abyssal peridotites (0.1198361 ± 20). Melt depletion trends defined between Os isotopes and melt extraction indices (e.g., Al2O3) allow an estimate of the primitive mantle (PM) composition, using only abyssal peridotites. This yields 187Os/188Os (0.1292 ± 25), and 186Os

  19. Project Teaches Students to Diagnose an Ailing Windows OS

    ERIC Educational Resources Information Center

    Yang, Baijan

    2007-01-01

    Troubleshooting a corrupted Windows operating system (OS) is a must-learn experience for computer technology students. To teach OS troubleshooting, the simplest approach involves introducing the available tools followed by the "how-to's." But how does a teacher teach his or her students to apply their knowledge in real-life scenarios and help them…

  20. Os odontoideum in identical twins: Comparative gene expression analysis

    PubMed Central

    Straus, David; Xu, Shunbin; Traynelis, Vincent C.

    2014-01-01

    Background: Os odontoideum is a well identified anomaly of the craniovertebral junction. Since its initial description, there has been a continuous debate regarding the nature of its etiology: Whether congenital or traumatic. We sought to compare the gene expression profiles in patients with congenital os odontoideum, those with traumatic os odontoideum and controls. Methods: We have evaluated a pair of identical twins both with os odontoideum. We identified two additional patients with and four subjects without os odontoideum. We analyzed the gene expression profiles in these patients using a custom TaqMan microarray and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). The relative gene expression profiles in the two identical twins, the two nontwin patients with os odontoideum and the controls were assessed. Results: A total of 213 genes with significantly different expression between the twin os odontoideum patients and the subjects without os odontoideum were detected. CACNG6, PHEX, CACNAD3, IL2, FAS, TUFT1, KIT, TGFBR2, and IGF2 were expressed at levels greater than 100-fold more in the twins. There were six genes with significantly different expression profiles in the twins as compared with the nontwin os odontoideum patients: CMK4, ATF1, PLCG1, TAB1, E2F3, and ATF4. There were no statistically significant differences in gene expression in the four patients with os odontoideum and the subjects without. Trends, however, were noted in MMP8, KIT, HIF1A, CREB3, PWHAZ, TGFBR1, NFKB2, FGFR1, IPO8, STAT1, COL1A1, and BMP3. Conclusions: Os odontoideum has multiple etiologies, both traumatic and congenital and perhaps some represent a combination of the two. This work has identified a number of genes that show increased expression in a pair of twins with congenital os odontoideum and also demonstrates trends in gene expression profiles between a larger group of os odontoideum patients and non-os patients. A number of these genes are related to

  1. Thermal stability of hexagonal OsB{sub 2}

    SciTech Connect

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; Cullen, David A.; Andrew Payzant, E.

    2014-11-15

    The synthesis of novel hexagonal ReB{sub 2}-type OsB{sub 2} ceramic powder was performed by high energy ball milling of elemental Os and B powders. Two different sources of B powder have been used for this mechanochemical synthesis. One B powder consisted of a mixture of amorphous and crystalline phases and a mixture of {sup 10}B and {sup 11}B isotopes with a fine particle size, while another B powder was a purely crystalline (rhombohedral) material consisting of enriched {sup 11}B isotope with coarse particle size. The same Os powder was used for the synthesis in both cases. It was established that, in the first case, the hexagonal OsB{sub 2} phase was the main product of synthesis with a small quantity of Os{sub 2}B{sub 3} phase present after synthesis as an intermediate product. In the second case, where coarse crystalline {sup 11}B powder was used as a raw material, only Os{sub 2}B{sub 3} boride was synthesized mechanochemically. The thermal stability of hexagonal OsB{sub 2} powder was studied by heating under argon up to 876 °C and cooling in vacuo down to −225 °C. During the heating, the sacrificial reaction 2OsB{sub 2}+3O{sub 2}→2Os+2B{sub 2}O{sub 3} took place due to presence of O{sub 2}/water vapor molecules in the heating chamber, resulting in the oxidation of B atoms and formation of B{sub 2}O{sub 3} and precipitation of Os metal out of the OsB{sub 2} lattice. As a result of such phase changes during heating, the lattice parameters of hexagonal OsB{sub 2} changed significantly. The shrinkage of the a lattice parameter was recorded in 276–426 °C temperature range upon heating, which was attributed to the removal of B atoms from the OsB{sub 2} lattice due to oxidation followed by the precipitation of Os atoms and formation of Os metal. While significant structural changes occurred upon heating due to presence of O{sub 2}, the hexagonal OsB{sub 2} ceramic demonstrated good phase stability upon cooling in vacuo with linear shrinkage of the lattice

  2. Transcriptional Activation of OsDERF1 in OsERF3 and OsAP2-39 Negatively Modulates Ethylene Synthesis and Drought Tolerance in Rice

    PubMed Central

    Zhang, Haiwen; Zhang, Zhijin; Quan, Ruidang; Zhou, Shirong; Huang, Rongfeng

    2011-01-01

    The phytohormone ethylene is a key signaling molecule that regulates a variety of developmental processes and stress responses in plants. Transcriptional modulation is a pivotal process controlling ethylene synthesis, which further triggers the expression of stress-related genes and plant adaptation to stresses; however, it is unclear how this process is transcriptionally modulated in rice. In the present research, we report the transcriptional regulation of a novel rice ethylene response factor (ERF) in ethylene synthesis and drought tolerance. Through analysis of transcriptional data, one of the drought-responsive ERF genes, OsDERF1, was identified for its activation in response to drought, ethylene and abscisic acid. Transgenic plants overexpressing OsDERF1 (OE) led to reduced tolerance to drought stress in rice at seedling stage, while knockdown of OsDERF1 (RI) expression conferred enhanced tolerance at seedling and tillering stages. This regulation was supported by negative modulation in osmotic adjustment response. To elucidate the molecular basis of drought tolerance, we identified the target genes of OsDERF1 using the Affymetrix GeneChip, including the activation of cluster stress-related negative regulators such as ERF repressors. Biochemical and molecular approaches showed that OsDERF1 at least directly interacted with the GCC box in the promoters of ERF repressors OsERF3 and OsAP2-39. Further investigations showed that OE seedlings had reduced expression (while RI lines showed enhanced expression) of ethylene synthesis genes, thereby resulting in changes in ethylene production. Moreover, overexpression of OsERF3/OsAP2-39 suppressed ethylene synthesis. In addition, application of ACC recovered the drought-sensitive phenotype in the lines overexpressing OsERF3, showing that ethylene production contributed to drought response in rice. Thus our data reveal that a novel ERF transcriptional cascade modulates drought response through controlling the ethylene

  3. Phosphate transporters OsPHT1;9 and OsPHT1;10 are involved in phosphate uptake in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We characterized the function of two rice phosphate (Pi) transporters: OsPHT1;9 (OsPT9) and OsPHT1;10 (OsPT10). OsPT9 and OsPT10 were expressed in the root epidermis, root hairs, and lateral roots, with the expression being specifically induced by Pi-starvation. In leaves, the expression of the two ...

  4. Bilateral Os Acromiale in a Division I Basketball Player

    PubMed Central

    Davlin, Christina D.; Fluker, Dave

    2003-01-01

    An unfused acromial epiphysis, called os acromiale, can become unstable and mobile when the deltoid contracts. This may cause pain and lead to impingement syndrome and rotator cuff tearing. After sustaining a direct blow to the right shoulder, a male division I basketball player was diagnosed with impingement syndrome and an os acromiale. Following failed conservative treatment, the athlete underwent arthroscopic subacromial decompression & debridement of the loose os acromiale in the right shoulder. One year later, following a fall on the left shoulder, the athlete was diagnosed with os acromiale, impingement syndrome and a superior labrum anterior-posterior (SLAP) lesion. Arthroscopic repair of the unstable type II SLAP lesion, together, with arthroscopic subacromial decompression, and resection of the os acromiale was performed on the left shoulder. Both surgeries were successful and the athlete was able to return to competition subsequent to completing a progressive shoulder rehabilitation program. Symptomatic os acromiale is rarely seen in young athletes. However, proper diagnosis and management is necessary for a successful recovery. Os acromiale should be considered as a part of the differential diagnosis in any athlete with rotator cuff impingement symptoms. PMID:24688280

  5. Sources of osmium to the modern oceans: New evidence from the 190Pt-186Os system

    USGS Publications Warehouse

    McDaniel, D.K.; Walker, R.J.; Hemming, S.R.; Horan, M.F.; Becker, H.; Grauch, R.I.

    2004-01-01

    High precision Os isotope analysis of young marine manganese nodules indicate that whereas the composition of modern seawater is radiogenic with respect to 187Os/188Os, it has 186Os/188Os that is within uncertainty of the chondritic value. Marine Mn nodule compositions thus indicate that the average continental source of Os to modern seawater had long-term high Re/Os compared to Pt/Os. Analyses of loess and freshwater Mn nodules support existing evidence that average upper continental crust (UCC) has resolvably suprachondritic 186Os/188Os, as well as radiogenic 187Os/188Os. Modeling the composition of seawater as a two-component mixture of oceanic/cosmic Os with chondritic Os compositions and continentally-derived Os demonstrates that, insofar as estimates for the composition of average UCC are accurate, congruently weathered average UCC cannot be the sole continental source of Os to seawater. Our analysis of four Cambrian black shales confirm that organic-rich sediments can have 187Os/188Os ratios that are much higher than average UCC, but 186Os/188Os compositions that are generally between those of chondrites and average-UCC. Preferential weathering of black shales can result in dissolved Os discharged to the ocean basins that has a much lower 186Os/188Os than does average upper crust. Modeling the available data demonstrates that augmentation of estimated average UCC compositions with less than 0.1% additional black shale and 1.4% additional ultramafic rock can produce a continental end-member Os isotopic composition that satisfies the requirements imposed by the marine Mn nodule data. The interplay of these two sources provides a mechanism by which the 187Os/188Os of seawater can change as sources and weathering conditions change, yet seawater 186Os/188Os varies only minimally. ?? 2004 Elsevier Ltd.

  6. 1. VIEW OS SOUTH FRONT OF BOILER HOUSE, WITH SCALE ...

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

    1. VIEW OS SOUTH FRONT OF BOILER HOUSE, WITH SCALE STICK, SHOWING HEAVY SCALES OFFICE TO LEFT, LOOKING NORTH - Marvine Colliery, Boiler House No. 2, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  7. Research on Separation of Three Powers Architecture for Trusted OS

    NASA Astrophysics Data System (ADS)

    Li, Yu; Zhao, Yong; Xin, Siyuan

    The privilege in the operating system (OS) often results in the break of confidentiality and integrity of the system. To solve this problem, several security mechanisms are proposed, such as Role-based Access Control, Separation of Duty. However, these mechanisms can not eliminate the privilege in OS kernel layer. This paper proposes a Separation of Three Powers Architecture (STPA). The authorizations in OS are divided into three parts: System Management Subsystem (SMS), Security Management Subsystem (SEMS) and Audit Subsystem (AS). Mutual support and mutual checks and balances which are the design principles of STPA eliminate the administrator in the kernel layer. Furthermore, the paper gives the formal description for authorization division using the graph theory. Finally, the implementation of STPA is given. Proved by experiments, the Separation of Three Powers Architecture we proposed can provide reliable protection for the OS through authorization division.

  8. Problems with Re-Os isochron determinations. [Abstract only

    NASA Technical Reports Server (NTRS)

    Papanastassiou, D. A.; Ngo, H. H.; Wasserburg, G. J.

    1994-01-01

    We have developed closed-system techniques for the equilibration of Os isotopes and for the calibration of Re and Os tracers using high-purity metals. The results show reproducibility of +/- 0.5% for calibrations of Os using different chunks of the same high-purity Os metal produced by vacuum arc melting. On a Re-Os evolution diagram the analyses of Negrillos and of Tocopilla are displaced along horizontal lines and are not consistent with a well-defined isochron. We conclude that is unclear whether whole-rock samples of irons of individual classes of iron meteorites (including the IIA class) define isochrons.In light of these observations, one must consider the evidence for phases in which Re and Os may become redistributed. We note that the IIA irons are composed of large or single kamacite crystals and do not contain taenite. This may hinder redistribution of Re and Os and may allow the IIA irons to define isochrons in preference to other magmatic iron classes. However, the IIA irons also include ubiquitous rhabdites, up to 20 mm in length, and troilite-daubreelite nodules. It has been observed that rhabdites are extremely rich in Pt-group elements. In addition to these considerations, Negrillos and Tocopilla were found in nitrate deposits and show evidence of corrosion. Therefore, it is possible that different samples of these meteorites have been differentially weathered, although our samples appeared fresh. We conclude that it is important to identify the phases in which Re and the PGEs are located and to address in detail the evidence for Re and Os remobilization.

  9. On-surface reaction of tetraphenylporphyrins with Os3(CO)12 precursors and Os clusters: A scanning tunnelling microscopy investigation

    NASA Astrophysics Data System (ADS)

    Sağlam, Özge; Yetik, Görsel; Reichert, Joachim; Barth, Johannes V.; Papageorgiou, Anthoula C.

    2016-04-01

    The ability of porphyrin molecules to incorporate metal atoms into the cavity of the macrocycle is the primary factor that enables the plethora of their applications. The fabrication and characterisation of surface confined metal-organic architectures by employing porphyrins promise unique technical applications in the field of nanotechnology. Here we report on the efforts to use triosmium dodecacarbonyl as a metal precursor for the on-surface Os functionalisation of porphyrins under ultra-high vacuum conditions. We address the effects of the temperature treatment of mixtures of tetraphenylporphyrins and the Os precursor molecules, which can decompose to yield Os clusters, on Ag(111) via scanning tunnelling microscopy, a technique that provides real-space visualisation of the reaction products formed. It is shown that free base porphyrins can be metallated to osmium porphyrins. Furthermore the presence of Os on the Ag(111) surface catalyses intramolecular cyclodehydrogenations in tetraphenylporphyrins, as well as intermolecular tetraphenylporphyrin polymerisation.

  10. Rice Stress Associated Protein 1 (OsSAP1) Interacts with Aminotransferase (OsAMTR1) and Pathogenesis-Related 1a Protein (OsSCP) and Regulates Abiotic Stress Responses

    PubMed Central

    Kothari, Kamakshi S.; Dansana, Prasant K.; Giri, Jitender; Tyagi, Akhilesh K.

    2016-01-01

    Stress associated proteins (SAPs) are the A20/AN1 zinc-finger containing proteins which can regulate the stress signaling in plants. The rice SAP protein, OsSAP1 has been shown to confer abiotic stress tolerance to plants, when overexpressed, by modulating the expression of endogenous stress-related genes. To further understand the mechanism of OsSAP1-mediated stress signaling, OsSAP1 interacting proteins were identified using yeast two-hybrid analysis. Two novel proteins, aminotransferase (OsAMTR1) and a SCP/TAPS or pathogenesis-related 1 class of protein (OsSCP) were found to interact with OsSAP1. The genes encoding OsAMTR1 and OsSCP were stress-responsive and showed higher expression upon abiotic stress treatments. The role of OsAMTR1 and OsSCP under stress was analyzed by overexpressing them constitutively in Arabidopsis and responses of transgenic plants were assessed under salt and water-deficit stress. The OsAMTR1 and OsSCP overexpressing plants showed higher seed germination, root growth and fresh weight than wild-type plants under stress conditions. Overexpression of OsAMTR1 and OsSCP affected the expression of many known stress-responsive genes which were not affected by the overexpression of OsSAP1. Moreover, the transcript levels of OsSCP and OsAMTR1 were also unaffected by the overexpression of OsSAP1. Hence, it was concluded that OsSAP1 regulates the stress responsive signaling by interacting with these proteins which further regulate the downstream stress responsive gene expression. PMID:27486471

  11. New Applications of the Re-187 - Os-187 and Pt-190 - Os-186 Isotope Systems to the Study of Iron Meteorites

    NASA Technical Reports Server (NTRS)

    Cook, D. L.; Walker, R. J.; Horan, M. F.

    2000-01-01

    Re-187 - Os-187 and Pt-190 - Os-186 isotope systems are applied to dating evolved iron meteorites. The Re-Os systematics of some evolved irons may indicate late stage system closure. This conclusion appears to be supported by a "young" Pt-Os isochron age.

  12. OS friendly microprocessor architecture: Hardware level computer security

    NASA Astrophysics Data System (ADS)

    Jungwirth, Patrick; La Fratta, Patrick

    2016-05-01

    We present an introduction to the patented OS Friendly Microprocessor Architecture (OSFA) and hardware level computer security. Conventional microprocessors have not tried to balance hardware performance and OS performance at the same time. Conventional microprocessors have depended on the Operating System for computer security and information assurance. The goal of the OS Friendly Architecture is to provide a high performance and secure microprocessor and OS system. We are interested in cyber security, information technology (IT), and SCADA control professionals reviewing the hardware level security features. The OS Friendly Architecture is a switched set of cache memory banks in a pipeline configuration. For light-weight threads, the memory pipeline configuration provides near instantaneous context switching times. The pipelining and parallelism provided by the cache memory pipeline provides for background cache read and write operations while the microprocessor's execution pipeline is running instructions. The cache bank selection controllers provide arbitration to prevent the memory pipeline and microprocessor's execution pipeline from accessing the same cache bank at the same time. This separation allows the cache memory pages to transfer to and from level 1 (L1) caching while the microprocessor pipeline is executing instructions. Computer security operations are implemented in hardware. By extending Unix file permissions bits to each cache memory bank and memory address, the OSFA provides hardware level computer security.

  13. Varied clinical presentation of os odontoideum: a case report

    PubMed Central

    Chrobak, Karen; Larson, Ryan; Stern, Paula J.

    2014-01-01

    Objective: To present a case of an os odontoideum and to provide insight into the varied clinical presentations. Clinical Features: A 54 year old man presented with chronic neck pain without headache. A clinical examination was performed and the chiropractor viewed his AP and lateral radiographs. Previous flexion/ extension radiographs and MRI imaging from 2009 were requested for review. The patient was diagnosed with grade II mechanical neck pain. Treatment was rendered that day which included spinal manipulation/ mobilization. Several days later the requested imaging reports were received and described the presence of an os odontoideum. Conclusion: In the presence of os odontoideum, familiarity with the signs and symptoms of potential cervical instability is imperative. Health care providers must remain diligent in their patient histories, physical exams, and imaging. This case highlights the importance of following up on imaging studies to rule out diagnoses that would involve treatment contraindications thus ensuring safe and effective treatment. PMID:25202154

  14. Integrating O/S models during conceptual design, part 1

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles E.

    1994-01-01

    The University of Dayton is pleased to submit this report to the National Aeronautics and Space Administration (NASA), Langley Research Center, which integrates a set of models for determining operational capabilities and support requirements during the conceptual design of proposed space systems. This research provides for the integration of the reliability and maintainability (R&M) model, both new and existing simulation models, and existing operations and support (O&S) costing equations in arriving at a complete analysis methodology. Details concerning the R&M model and the O&S costing model may be found in previous reports accomplished under this grant (NASA Research Grant NAG1-1327). In the process of developing this comprehensive analysis approach, significant enhancements were made to the R&M model, updates to the O&S costing model were accomplished, and a new simulation model developed. This is the 1st part of a 3 part technical report.

  15. Os trigonum syndrome: use of bone scan in the diagnosis

    SciTech Connect

    Johnson, R.P.; Collier, B.D.; Carrera, G.F.

    1984-08-01

    The os trigonum is an accessory bone of the foot found in 7% of the normal adult population. It is located at the posterolateral projection of the talus, and can occasionally give rise to symptoms of acute and chronic unexplained ankle pain. We report three patients, one with acute fracture and two with chronic ankle symptoms. Technetium 99 methylene diphosphonate showed intense focal uptake at the posterior talus pointing to the os trigonum as the site of symptoms. It was excised in two patients with complete relief. The third went on to develop an asymptomatic nonunion. We recommend bone scanning as a procedure that is helpful in delineating obscure pain in the ankle that may be due to chronic irritative nonunion of the os trigonum.

  16. Isotope shift of the electric-dipole transition in Os-

    NASA Astrophysics Data System (ADS)

    Kellerbauer, A.; Canali, C.; Fischer, A.; Warring, U.; Fritzsche, S.

    2011-12-01

    The isotope shift of the bound-bound electric dipole transition at 1162.75 nm in the osmium anion was measured by high-precision collinear laser spectroscopy. The transition was observed in all naturally occurring isotopes, including 184Os- with a natural abundance of 0.02%. We combined the data with our prior measurements of the hyperfine structure in 187Os- and 189Os- and used them to determine experimental values for the isotope shift coefficients. The normal mass shift, specific mass shift, and field shift coefficients were found to be MNMS=141.4 GHz u, MSMS=2.4(12.6) THz u, and F=16.2(9.9) GHz fm-2, respectively. Theoretical values for the MSMS and F parameters were calculated based on a series of relativistic configuration interaction computations and a Fermi-like charge distribution and found to be in good agreement with the experimental values.

  17. The os penis of the frugivorous bat, Eidolon helvum (Kerr).

    PubMed

    Nwoha, P U; Caxton-Martins, A E; Baxter-Grillo, D L

    2000-01-01

    The os penis reported in some species of the mammalian order was observed in the juvenile and adult penes of the friguvorous African bat, Eidolon helvum. The morphology of the os penis in Eidolon helvum differs from that observed in bat species and other mammalian order. In the adult form it is large, disc-shaped and located at the distal segment of the penile organ. The proximal segment of the penis does not contain any bone. In the juvenile bat the os penis is made of two separate bones located longitudinally close to each other at the distal third of the penile tissue. The distal location in both the juvenile and the adult poses a question about the true function of this tissue. The bone may function in Eidolon helvum to support erection of the penis more for micturition than for intromission.

  18. Mini-Ckpts: Surviving OS Failures in Persistent Memory

    SciTech Connect

    Fiala, David; Mueller, Frank; Ferreira, Kurt Brian; Engelmann, Christian

    2016-01-01

    Concern is growing in the high-performance computing (HPC) community on the reliability of future extreme-scale systems. Current efforts have focused on application fault-tolerance rather than the operating system (OS), despite the fact that recent studies have suggested that failures in OS memory are more likely. The OS is critical to a system's correct and efficient operation of the node and processes it governs -- and in HPC also for any other nodes a parallelized application runs on and communicates with: Any single node failure generally forces all processes of this application to terminate due to tight communication in HPC. Therefore, the OS itself must be capable of tolerating failures. In this work, we introduce mini-ckpts, a framework which enables application survival despite the occurrence of a fatal OS failure or crash. Mini-ckpts achieves this tolerance by ensuring that the critical data describing a process is preserved in persistent memory prior to the failure. Following the failure, the OS is rejuvenated via a warm reboot and the application continues execution effectively making the failure and restart transparent. The mini-ckpts rejuvenation and recovery process is measured to take between three to six seconds and has a failure-free overhead of between 3-5% for a number of key HPC workloads. In contrast to current fault-tolerance methods, this work ensures that the operating and runtime system can continue in the presence of faults. This is a much finer-grained and dynamic method of fault-tolerance than the current, coarse-grained, application-centric methods. Handling faults at this level has the potential to greatly reduce overheads and enables mitigation of additional fault scenarios.

  19. Expression of OsMATE1 and OsMATE2 alters development, stress responses and pathogen susceptibility in Arabidopsis

    PubMed Central

    Tiwari, Manish; Sharma, Deepika; Singh, Munna; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar

    2014-01-01

    Multidrug and Toxic compound Extrusion proteins (MATE) are a group of secondary active transporters with ubiquitous occurrences in all domains of life. This is a newly characterized transporter family with limited functional knowledge in plants. In this study, we functionally characterised two members of rice MATE gene family, OsMATE1 and OsMATE2 through expression in heterologous system, Arabidopsis. Expression of OsMATEs in Arabidopsis altered growth and morphology of transgenic plants. Genome-wide expression analysis revealed modulation of genes involved in plant growth, development and biotic stress in transgenic lines. Transgenic plants displayed sensitivity for biotic and abiotic stresses. Elevated pathogen susceptibility of transgenic lines was correlated with reduced expressions of defence related genes. Promoter and cellular localization studies suggest that both MATEs express in developing and reproductive organs and are plasma-membrane localised. Our results reveal that OsMATE1 and OsMATE2 regulate plant growth and development as well as negatively affect disease resistance. PMID:24492654

  20. [Results after fracture of the os calcis (author's transl)].

    PubMed

    Ostapowicz, G; Sateri, F; Wessel, G

    1978-02-10

    A double study over a period of 40 years was undertaken--from 1935 to 1954 in Berlin and from 1955 to 1976 in Salzgitter--including a total of 393 fractures of the os calcis. The results of different types of treatment are presented. It is the type and severity of the fractures, not the way of treatment which determines the outcome. 161 patients have been followed clinically and radiologically at least 5 years after fracture of the os calcis. Third degree fractures were objectively and subjectively less favourable regardless of therapy. Active surgical treatment should be post-poned and consist in fusion of the subtalar joint.

  1. Resetting of Re-Os ages in mantle rocks

    NASA Astrophysics Data System (ADS)

    Becker, H.; Gawronski, T.; Wang, Z.

    2011-12-01

    Among long-lived geochronometers, the Re-Os decay system is unique in that it permits to obtain direct age information on past melt extraction events in the mantle. Some studies have discovered ancient melting residues in oceanic peridotites emplaced on young seafloor [1-3]. Other work indicates that melt transport and reactive infiltration may affect the Re-Os systematics of both depleted and fertile peridotites to variable extent [4-6]. Open system polybaric melting of depleted lherzolites and harzburgites should lead to removal of basaltic components and at the same time partial or complete equilibration with infiltrating magma. If such magma carries radiogenic Os, it will lead to partial or complete resetting of the Re-Os clock. This is what may have occurred in many abyssal peridotites [e.g. 2, 7], although, the parameters that control isotopic resetting, the timing, extent and controls on equilibration with melts carrying radiogenic Os are still incompletely understood. Studies of well-characterized Phanerozoic peridotite massifs that represent former ocean-continent transitions and analogues of modern slow spreading environments do offer some additional insight. Re-Os data on the Ligurian peridotite massifs [8,9], the Lanzo peridotite [9], and peridotites from the Ivrea zone [10,11] suggest addition of radiogenic Os to some, but not all, harzburgites and depleted lherzolites. The source of the radiogenic Os may have been either local (melting of pyroxenites) or external. Fertile lherzolites in these massifs often display petrological and geochemical evidence for refertilization, but the timing of magmatic processes is not always clear. In the Ivrea zone, Sm-Nd dates obtained on clinopyroxenes from peridotites are Paleozoic [12], as are some Os model ages of peridotites [10, 11], however, the spectrum of Re-Os (primitive mantle) model ages ranges between 0.2 and 1.6 Ga (median 0.5 Ga). Hence, it is likely that extensive magmatic re-equilibration occurred in

  2. Addressing Small Computers in the First OS Course

    ERIC Educational Resources Information Center

    Nutt, Gary

    2006-01-01

    Small computers are emerging as important components of the contemporary computing scene. Their operating systems vary from specialized software for an embedded system to the same style of OS used on a generic desktop or server computer. This article describes a course in which systems are classified by their hardware capability and the…

  3. Hexagonal OsB2: Sintering, microstructure and mechanical properties

    DOE PAGES

    Xie, Zhilin; Lugovy, Mykola; Orlovskaya, Nina; ...

    2015-02-07

    In this study, the metastable high pressure ReB2-type hexagonal OsB2 bulk ceramics was produced by spark plasma sintering. The phase composition, microstructure, and mechanical behavior of the sintered OsB2 were studied by X-ray diffraction, optical microscopy, TEM, SEM, EDS, and nanoindentation. The produced ceramics was rather porous and contained a mixture of hexagonal (~80 wt.%) and orthorhombic (~20 wt.%) phases as identified by X-ray diffraction and EBSD analysis. Two boron-rich phases, which do not contain Os, were also identified by TEM and SEM/EDS analysis. Nanoindentation measurements yielded a hardness of 31 ± 9 GPa and Young’s modulus of 574 ±more » 112 GPa, indicating that the material is rather hard and very stiff; but, it is very prone to crack formation and propagation, which is indicative of a very brittle nature of this material. Improvements in the sintering regime are required in order to produce dense, homogeneous and single phase hexagonal OsB2 bulk ceramics.« less

  4. Compliance of blood donation apps with mobile OS usability guidelines.

    PubMed

    Ouhbi, Sofia; Fernández-Alemán, José Luis; Pozo, José Rivera; Bajta, Manal El; Toval, Ambrosio; Idri, Ali

    2015-06-01

    The aim of this paper is to employ the guidelines of Android, iOS, Blackberry and Windows Phone to analyze the usability compliance of free blood donation (BD) apps. An analysis process based on a systematic review protocol is used to select free BD apps. An assessment is conducted using a questionnaire composed of 13 questions concerning the compliance of free BD apps with Android, Blackberry, iOS and Windows Phone usability guidelines. A total of 133 free BD apps have been selected from the 188 BD apps identified. Around 63% of the free BD apps selected have a good compliance with mobile OS usability recommendations. Around 72% of Android, 57% of Windows Phone, 33% of iOS and 33% of Blackberry BD apps have a high usability score. The aspect of BD app behavior should be improved along with some style components: the use of pictures to explain ideas and the adaptation of the app to both horizontal and vertical orientations. Structure patterns should also be used to improve the structure aspect of a BD app. Usability is a quality aspect that should be improved in current BD apps. Our study provides smartphone users with a list of usable free BD apps and BD app developers with recommendations.

  5. Integrated, Kerberized Login on MacOS X

    NASA Technical Reports Server (NTRS)

    Hotz, Henry B.

    2006-01-01

    Context for this information. MacOS X login process and available hooks. Authorization Services configuration. Authorization Services plug-in s. Kerberos plug-in s. Other bugs and recommendations. Authorization Services Called by loginwindow, screen saver and fast user switching. It calls Directory Services, Login Hook, and Login Items (System Preferences).

  6. pOsNAR2.1:OsNAR2.1 expression enhances nitrogen uptake efficiency and grain yield in transgenic rice plants.

    PubMed

    Chen, Jingguang; Fan, Xiaoru; Qian, Kaiyun; Zhang, Yong; Song, Miaoquan; Liu, Yu; Xu, Guohua; Fan, Xiaorong

    2017-02-22

    The nitrate (NO3-) transporter has been selected as an important gene maker in the process of environmental adoption in rice cultivars. In this work, we transferred another native OsNAR2.1 promoter with driving OsNAR2.1 gene into rice plants. The transgenic lines with exogenous pOsNAR2.1:OsNAR2.1 constructs showed enhanced OsNAR2.1 expression level, compared with wild type (WT), and (15) N influx in roots increased 21%-32% in response to 0.2 mm and 2.5 mm 15NO3- and 1.25 mm (15) NH4(15) NO3 . Under these three N conditions, the biomass of the pOsNAR2.1:OsNAR2.1 transgenic lines increased 143%, 129% and 51%, and total N content increased 161%, 242% and 69%, respectively, compared to WT. Furthermore in field experiments we found the grain yield, agricultural nitrogen use efficiency (ANUE), and dry matter transfer of pOsNAR2.1:OsNAR2.1 plants increased by about 21%, 22% and 21%, compared to WT. We also compared the phenotypes of pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines in the field, found that postanthesis N uptake differed significantly between them, and in comparison with the WT. Postanthesis N uptake (PANU) increased approximately 39% and 85%, in the pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines, respectively, possibly because OsNRT2.1 expression was less in the pOsNAR2.1:OsNAR2.1 lines than in the pOsNAR2.1:OsNRT2.1 lines during the late growth stage. These results show that rice NO3(-) uptake, yield and NUE were improved by increased OsNAR2.1 expression via its native promoter.

  7. Agronomic nitrogen-use efficiency of rice can be increased by driving OsNRT2.1 expression with the OsNAR2.1 promoter.

    PubMed

    Chen, Jingguang; Zhang, Yong; Tan, Yawen; Zhang, Min; Zhu, Longlong; Xu, Guohua; Fan, Xiaorong

    2016-08-01

    The importance of the nitrate (NO3-) transporter for yield and nitrogen-use efficiency (NUE) in rice was previously demonstrated using map-based cloning. In this study, we enhanced the expression of the OsNRT2.1 gene, which encodes a high-affinity NO3- transporter, using a ubiquitin (Ubi) promoter and the NO3--inducible promoter of the OsNAR2.1 gene to drive OsNRT2.1 expression in transgenic rice plants. Transgenic lines expressing pUbi:OsNRT2.1 or pOsNAR2.1:OsNRT2.1 constructs exhibited the increased total biomass including yields of approximately 21% and 38% compared with wild-type (WT) plants. The agricultural NUE (ANUE) of the pUbi:OsNRT2.1 lines decreased to 83% of that of the WT plants, while the ANUE of the pOsNAR2.1:OsNRT2.1 lines increased to 128% of that of the WT plants. The dry matter transfer into grain decreased by 68% in the pUbi:OsNRT2.1 lines and increased by 46% in the pOsNAR2.1:OsNRT2.1 lines relative to the WT. The expression of OsNRT2.1 in shoot and grain showed that Ubi enhanced OsNRT2.1 expression by 7.5-fold averagely and OsNAR2.1 promoters increased by about 80% higher than the WT. Interestingly, we found that the OsNAR2.1 was expressed higher in all the organs of pUbi:OsNRT2.1 lines; however, for pOsNAR2.1:OsNRT2.1 lines, OsNAR2.1 expression was only increased in root, leaf sheaths and internodes. We show that increased expression of OsNRT2.1, especially driven by OsNAR2.1 promoter, can improve the yield and NUE in rice.

  8. Re-187-Os-187, Pt-190-Os-186 Isotopic and Highly Siderophile Element Systematics of Group IVA Irons

    NASA Technical Reports Server (NTRS)

    Walker, R. J.; McCoy, T. J.; Schulte, R. F.; McDonough, W. F.; Ash, R. D.

    2005-01-01

    We have recently completed Re-187-Os-187 and Pt-190-Os-186 isotopic and elemental studies of the two largest magmatic iron meteorite groups, IIAB and IIIAB [1]. These studies revealed closed-system behavior of both isotopic systems, but complex trace element behavior for Re, Pt and Os in group IIIAB. Here we examine isotopic and trace elemental systematics of group IVA irons. The IVA irons are not as extensively fractionated as IIAB and IIIAB and their apparently less complex crystallization history may make for more robust interpretation of the relative partitioning behavior of Re, Pt and Os, as well as the other highly siderophile elements (HSE) measured here; Pd, Ru and Ir [e.g. 2]. An additional goal of our continuing research plan for iron meteorites is to assess the possibility of relating certain ungrouped irons with major groups via trace element modeling. Here, the isotopic and trace element systematics of the ungrouped irons Nedagolla and EET 83230 are compared with the IVA irons.

  9. OsHAC1;1 and OsHAC1;2 Function as Arsenate Reductases and Regulate Arsenic Accumulation.

    PubMed

    Shi, Shulin; Wang, Tao; Chen, Ziru; Tang, Zhong; Wu, Zhongchang; Salt, David E; Chao, Dai-Yin; Zhao, Fang-Jie

    2016-11-01

    Rice is a major dietary source of the toxic metalloid arsenic (As). Reducing its accumulation in rice (Oryza sativa) grain is of critical importance to food safety. Rice roots take up arsenate and arsenite depending on the prevailing soil conditions. The first step of arsenate detoxification is its reduction to arsenite, but the enzyme(s) catalyzing this reaction in rice remains unknown. Here, we identify OsHAC1;1 and OsHAC1;2 as arsenate reductases in rice. OsHAC1;1 and OsHAC1;2 are able to complement an Escherichia coli mutant lacking the endogenous arsenate reductase and to reduce arsenate to arsenite. OsHAC1:1 and OsHAC1;2 are predominantly expressed in roots, with OsHAC1;1 being abundant in the epidermis, root hairs, and pericycle cells while OsHAC1;2 is abundant in the epidermis, outer layers of cortex, and endodermis cells. Expression of the two genes was induced by arsenate exposure. Knocking out OsHAC1;1 or OsHAC1;2 decreased the reduction of arsenate to arsenite in roots, reducing arsenite efflux to the external medium. Loss of arsenite efflux was also associated with increased As accumulation in shoots. Greater effects were observed in a double mutant of the two genes. In contrast, overexpression of either OsHAC1;1 or OsHAC1;2 increased arsenite efflux, reduced As accumulation, and enhanced arsenate tolerance. When grown under aerobic soil conditions, overexpression of either OsHAC1;1 or OsHAC1;2 also decreased As accumulation in rice grain, whereas grain As increased in the knockout mutants. We conclude that OsHAC1;1 and OsHAC1;2 are arsenate reductases that play an important role in restricting As accumulation in rice shoots and grain.

  10. OsSRO1a Interacts with RNA Binding Domain-Containing Protein (OsRBD1) and Functions in Abiotic Stress Tolerance in Yeast

    PubMed Central

    Sharma, Shweta; Kaur, Charanpreet; Singla-Pareek, Sneh L.; Sopory, Sudhir K.

    2016-01-01

    SRO1 is an important regulator of stress and hormonal response in plants and functions by interacting with transcription factors and several other proteins involved in abiotic stress response. In the present study, we report OsRBD1, an RNA binding domain 1- containing protein as a novel interacting partner of OsSRO1a from rice. The interaction of OsSRO1a with OsRBD1 was shown in yeast as well as in planta. Domain–domain interaction study revealed that C-terminal RST domain of OsSRO1a interacts with the N-terminal RRM1 domain of OsRBD1 protein. Both the proteins were found to co-localize in nucleus. Transcript profiling under different stress conditions revealed co-regulation of OsSRO1a and OsRBD1 expression under some abiotic stress conditions. Further, co-transformation of both OsSRO1a and OsRBD1 in yeast conferred enhanced tolerance toward salinity, osmotic, and methylglyoxal treatments. Our study suggests that the interaction of OsSRO1a with OsRBD1 confers enhanced stress tolerance in yeast and may play an important role under abiotic stress responses in plants. PMID:26870074

  11. Auxin regulated OsRGP1 and OsSuS are involved in the gravitropic bending of rice shoot bases

    NASA Astrophysics Data System (ADS)

    Hu, Liwei; Cui, Dayong; Cai, Weiming

    The gravitropic bending of rice shoot in horizontal position results from differential elongation of cells between two halves of shoot bases. In our experiment, reversibly glycosylated polypeptide (OsRGP1), sucrose synthase (OsSuS) genes which related to sugar metabolism were identified by suppressive subtractive hybridization (SSH) in gravitropism in rice shoot bases. Realtime RT-PCR were used to study the expression of two genes in detail. OsRGP1 and OsSuS were differentially induced in the abaxial (lower) side of rice shoot bases during gravitropism. The OsRGP1 and OsSuS expression were regulated by auxin. The sequence analysis of their promoters was in concurrence. TIBA treatment could inhibit the asymmetrical expression of OsRGP1 and OsSuS in gravitropism in rice shoot bases. In addition, there was more hexose in the lower side of rice shoot bases in gravitropism. Our data suggested that asymmetric redistribution of auxin following gravistimulation resulted in the different localized expression of OsRGP1 and OsSuS. It is possible that asymmetrical expression of OsSuS resulted in the asymmetrical distribution of hexose and asymmetrical expression of OsRGP1 induced the synthesis of cell wall polysaccharides in the lower half of rice shoot bases. Hexose and cell wall polysaccharides accumulation in lower side of rice shoot bases might contribute to the cell expansion, thus leading to gravitropic bending.

  12. Pacific 187Os/188Os isotope chemistry and U-Pb geochronology: Synchroneity of global Os isotope change across OAE 2

    NASA Astrophysics Data System (ADS)

    Du Vivier, A. D. C.; Selby, D.; Condon, D. J.; Takashima, R.; Nishi, H.

    2015-10-01

    Studies of OAE 2 sections beyond the Atlantic Ocean, Western Interior Seaway (WIS) and European pelagic shelf are limited. Here, we present initial osmium isotope stratigraphy (187Os/188Os-Osi) from two proto-Pacific sites that span the Cenomanian-Turonian boundary interval (CTBI): the Yezo Group (YG) section, Hokkaido, Japan, and the Great Valley Sequence (GVS), California, USA; to evaluate the 187Os/188Os seawater chemistry of the proto-Pacific. Additionally we combine new 206Pb/238U zircon CA-ID-TIMS geochronology from five volcanic tuff horizons of the Yezo Group section to test and facilitate inter-basinal integration with the WIS using radio-isotopically constrained age-depth models for both sections, and quantitatively constrain the absolute timing and duration of events across the CTBI. The YG shows an almost identical Osi profile to that of the WIS, and very similar to that of other sites of the proto-Atlantic and European pelagic oceans (Turgeon and Creaser, 2008; Du Vivier et al., 2014). The characteristics of the Osi profile are radiogenic and heterogeneous (∼0.55-0.85) prior to the OAE 2, and synchronous with the inferred OAE 2 onset the Osi abruptly become unradiogenic and remain relatively homogeneous (∼0.20-0.30) before showing a gradual return to more radiogenic Osi (∼ 0.70) throughout the middle to late OAE 2. A206Pb/238U zircon age of an interbedded tuff (HK017) in the adjacent horizon to the first unradiogenic Osi value constrains the age of the Osi inflection at 94.44 ± 0.14 Ma. This age, including uncertainty, agrees with the interpolated age of the same point in the Osi profile (94.28 ± 0.25 Ma) in the only other dated OAE 2 section, the WIS; indicating a coeval shift in seawater chemistry associated with volcanism at the OAE 2 onset at the levels of temporal resolution (ca. 0.1 Myr). Further, prior to the onset of OAE 2 an enhanced radiogenic inflection in the Osi profile of the YG is correlative, within uncertainty, with a similar

  13. Comprehensive Analysis and Expression Profiling of the OsLAX and OsABCB Auxin Transporter Gene Families in Rice (Oryza sativa) under Phytohormone Stimuli and Abiotic Stresses

    PubMed Central

    Chai, Chenglin; Subudhi, Prasanta K.

    2016-01-01

    The plant hormone auxin regulates many aspects of plant growth and developmental processes. Auxin gradient is formed in plant as a result of polar auxin transportation by three types of auxin transporters such as OsLAX, OsPIN, and OsABCB. We report here the analysis of two rice auxin transporter gene families, OsLAX and OsABCB, using bioinformatics tools, publicly accessible microarray data, and quantitative RT-PCR. There are 5 putative OsLAXs and 22 putative OsABCBs in rice genome, which were mapped on 8 chromosomes. The exon-intron structure of OsLAX genes and properties of deduced proteins were relatively conserved within grass family, while that of OsABCB genes varied greatly. Both constitutive and organ/tissue specific expression patterns were observed in OsLAXs and OsABCBs. Analysis of evolutionarily closely related “gene pairs” together with organ/tissue specific expression revealed possible “function gaining” and “function losing” events during rice evolution. Most OsLAX and OsABCB genes were regulated by drought and salt stress, as well as hormonal stimuli [auxin and Abscisic Acid (ABA)], which suggests extensive crosstalk between abiotic stresses and hormone signaling pathways. The existence of large number of auxin and stress related cis-regulatory elements in promoter regions might account for their massive responsiveness of these genes to these environmental stimuli, indicating complexity of regulatory networks involved in various developmental and physiological processes. The comprehensive analysis of OsLAX and OsABCB auxin transporter genes in this study would be helpful for understanding the biological significance of these gene families in hormone signaling and adaptation of rice plants to unfavorable environments. PMID:27200061

  14. Erlichmanite /OsS sub 2/, a new mineral.

    NASA Technical Reports Server (NTRS)

    Snetsinger, K. G.

    1971-01-01

    Natural osmium disulfide (termed erlichmanite) was recognized in two occurrences on the basis of electron probe and X-ray data. One occurrence is in grains of platinum-metal sand from California, the other in a platinum-metal nugget from Western Ethiopian laterites. California erlichmanite has Os 68.0, Ir 2.6, Rh 3.8, Ru 0.4, Pd 0.5, and S 25.2, summation of 100.5 wt. %, the number of metal atoms being 1.06 on the basis of 2.00 sulfurs. Ethiopian material has higher Rh and Ir and lower Os. Both are optically isotropic. Spotty X-ray reflections from a 15-micron particle of California erlichmanite give rise to d spacing which match those of synthetic cubic osmium disulfide. Erlichmanite is defined as a cubic disulfide in which osmium is the most abundant metal atom.

  15. Ru, Re, Os, Pt and Au in iron meteorites

    NASA Technical Reports Server (NTRS)

    Pernicka, Ernst; Wasson, John T.

    1987-01-01

    Neutron activation analysis is used to ascertain the proportions of Ru, Re, Os, and Pt refractory siderophiles, and moderately volatile Au, in 41 iron meteorites. The Ni-element trends defined for groups IID and IIIF support a magmatic origin; in addition, the results obtained for groups IAB and IIICD contrast with trends observed in magmatic groups, where the Ru and Pt slopes are substantially less steep. In group IIIAB, at Ni concentrations above 90 mg/g, the steep decrease of Re, Os, and Ir with Ni levels off, and the interelement ratios exhibit considerable scatter. These observations may be explained in terms of the contamination of the residual molten core with small amounts of late primitive melts draining from the mantle.

  16. Excited states and reduced transition probabilities in 168Os

    NASA Astrophysics Data System (ADS)

    Grahn, T.; Stolze, S.; Joss, D. T.; Page, R. D.; Sayǧı, B.; O'Donnell, D.; Akmali, M.; Andgren, K.; Bianco, L.; Cullen, D. M.; Dewald, A.; Greenlees, P. T.; Heyde, K.; Iwasaki, H.; Jakobsson, U.; Jones, P.; Judson, D. S.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Lumley, N.; Mason, P. J. R.; Möller, O.; Nomura, K.; Nyman, M.; Petts, A.; Peura, P.; Pietralla, N.; Pissulla, Th.; Rahkila, P.; Sapple, P. J.; Sarén, J.; Scholey, C.; Simpson, J.; Sorri, J.; Stevenson, P. D.; Uusitalo, J.; Watkins, H. V.; Wood, J. L.

    2016-10-01

    The level scheme of the neutron-deficient nuclide 168Os has been extended and mean lifetimes of excited states have been measured by the recoil distance Doppler-shift method using the JUROGAM γ -ray spectrometer in conjunction with the IKP Köln plunger device. The 168Osγ rays were measured in delayed coincidence with recoiling fusion-evaporation residues detected at the focal plane of the RITU gas-filled separator. The ratio of reduced transition probabilities B (E 2 ;41+→21+) /B (E 2 ;21+→01+) is measured to be 0.34(18), which is very unusual for collective band structures and cannot be reproduced by interacting boson model (IBM-2) calculations based on the SkM* energy-density functional.

  17. Os zygomaticum bipartitum: frequency distribution in major human populations

    PubMed Central

    HANIHARA, TSUNEHIKO; ISHIDA, HAJIME; DODO, YUKIO

    1998-01-01

    The frequency of the Os zygomaticum bipartitum was examined in major human populations around the world. Eastern Asians have a higher frequency of the bipartite zygomatic bone than any other geographical groups. The arctic peoples, Amerindians and the Oceanians, who all may have derived from eastern Asian population stocks, have a considerably low frequency of this trait. The frequency distribution from East/Southeast Asia to Africa and Europe through South/Central/West Asia suggests some clinality for the bipartite zygomatic bone. The second peak in the frequency is seen in Subsaharan Africa. The clinal variation with no identifiable regulation by subsistence patterns and environmental factors suggested a genetic background for the occurrence of the Os zygomaticum bipartitum. PMID:9723981

  18. Os acromiale: population differences and their etiological significance.

    PubMed

    Case, D T; Burnett, S E; Nielsen, T

    2006-01-01

    The os acromiale is an accessory bone resulting from failure of the acromial apophysis to fuse to the scapula. It is a relatively frequent defect affecting 4-18% of most large skeletal series. The etiology of os acromiale is poorly understood, and two competing hypotheses have been proposed: (1) that the accessory bone represents a genetic defect, and (2) that it results from mechanical stress on the developing acromion. In order to assess the evidence for these two hypotheses, os acromiale frequencies from a South African cadaver sample (n = 494) were compared to frequencies from a medieval Danish archaeological sample (n = 532). The South African frequency (18.2%) was significantly higher than the medieval Danish frequency (7.7%, p < 0.0001). These results mirror those of another study comparing African- and Euro-Americans, and tend to support the genetic hypothesis. However, a left side bias (72%) was also found among the South Africans (p = 0.013), lending some support to the mechanical stress hypothesis. Sex and age biases were also examined but were not found. In order to further test the mechanical hypothesis, the medieval Danes were divided into groups of higher and lower socioeconomic status based upon cemetery type. Lower status individuals were presumed to have engaged in strenuous labor activities more often and at a younger age than higher status individuals. However, comparison of these two groups failed to demonstrate a significant frequency difference (p = 0.105). Based on the results of this study, it is suggested that a third etiology combining a genetic predisposition for os acromiale with mechanical stress as the proximate cause should also be considered.

  19. A review of elongation of os calcis for flat feet.

    PubMed

    Phillips, G E

    1983-01-01

    Between 1959 and 1974 the late Dillwyn Evans treated severe symptomatic flat feet by elongating the os calcis. The long-term follow-up of 20 of these patients with a total of 23 feet is presented 7 to 20 years after the operation. At review 17 of the 23 feet showed very good or good results and it was concluded that this is a useful procedure for severe cases of flat feet which appears to stand the test of time.

  20. The influence of extraterrestrial material on the late Eocene marine Os isotope record

    NASA Astrophysics Data System (ADS)

    Paquay, François S.; Ravizza, Greg; Coccioni, Rodolfo

    2014-11-01

    A reconstruction of seawater 187Os/188Os ratios during the late Eocene (∼36-34 Ma), based upon bulk sediment analyses from the sub-Antarctic Southern Atlantic Ocean (Ocean Drilling Program (ODP) Site 1090), Eastern Equatorial Pacific Ocean (ODP Sites 1218 and 1219) and the uplifted (land-based) Tethyan section (Massignano, Italy), confirms that the previously reported abrupt shift to lower 187Os/188Os is a unique global feature of the marine Os isotope record that occurs in magnetochron C16n.1n. This feature is interpreted to represent the change in seawater 187Os/188Os caused by the Popigai impact event. Higher in the Massignano section, two other iridium anomalies previously proposed to represent additional impact events do not show a comparable excursion to low 187Os/188Os, suggesting that these horizons do not record multiple large impacts. Comparison of records from three different ocean basins indicates that seawater 187Os/188Os begins to decline in advance of the Popigai impact event. At Massignano this decline coincides with a previously reported episode of elevated 3He flux, suggesting that increased influx of interplanetary dust particles (IDPs) contributed to the pre-impact shift in 187Os/188Os and not to the longer-term latest Eocene 187Os/188Os decline that occurred ∼1 million year after the Popigai impact event.

  1. OsHUS1 facilitates accurate meiotic recombination in rice.

    PubMed

    Che, Lixiao; Wang, Kejian; Tang, Ding; Liu, Qiaoquan; Chen, Xiaojun; Li, Yafei; Hu, Qing; Shen, Yi; Yu, Hengxiu; Gu, Minghong; Cheng, Zhukuan

    2014-06-01

    Meiotic recombination normally takes place between allelic sequences on homologs. This process can also occur between non-allelic homologous sequences. Such ectopic interaction events can lead to chromosome rearrangements and are normally avoided. However, much remains unknown about how these ectopic interaction events are sensed and eliminated. In this study, using a screen in rice, we characterized a homolog of HUS1 and explored its function in meiotic recombination. In Oshus1 mutants, in conjunction with nearly normal homologous pairing and synapsis, vigorous, aberrant ectopic interactions occurred between nonhomologous chromosomes, leading to multivalent formation and subsequent chromosome fragmentation. These ectopic interactions relied on programmed meiotic double strand breaks and were formed in a manner independent of the OsMER3-mediated interference-sensitive crossover pathway. Although early homologous recombination events occurred normally, the number of interference-sensitive crossovers was reduced in the absence of OsHUS1. Together, our results indicate that OsHUS1 might be involved in regulating ectopic interactions during meiosis, probably by forming the canonical RAD9-RAD1-HUS1 (9-1-1) complex.

  2. O/S analysis of conceptual space vehicles. Part 1

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles E.

    1995-01-01

    The application of recently developed computer models in determining operational capabilities and support requirements during the conceptual design of proposed space systems is discussed. The models used are the reliability and maintainability (R&M) model, the maintenance simulation model, and the operations and support (O&S) cost model. In the process of applying these models, the R&M and O&S cost models were updated. The more significant enhancements include (1) improved R&M equations for the tank subsystems, (2) the ability to allocate schedule maintenance by subsystem, (3) redefined spares calculations, (4) computing a weighted average of the working days and mission days per month, (5) the use of a position manning factor, and (6) the incorporation into the O&S model of new formulas for computing depot and organizational recurring and nonrecurring training costs and documentation costs, and depot support equipment costs. The case study used is based upon a winged, single-stage, vertical-takeoff vehicle (SSV) designed to deliver to the Space Station Freedom (SSF) a 25,000 lb payload including passengers without a crew.

  3. OsJAR1 and OsJAR2 are jasmonyl-L-isoleucine synthases involved in wound- and pathogen-induced jasmonic acid signalling.

    PubMed

    Wakuta, Shinji; Suzuki, Erika; Saburi, Wataru; Matsuura, Hideyuki; Nabeta, Kensuke; Imai, Ryozo; Matsui, Hirokazu

    2011-06-17

    The synthesis of JA-Ile was catalysed by JA-Ile synthase, which is a member of the group I GH3 family of proteins. Here, we showed evidence that OsGH3.5 (OsJAR1) and OsGH3.3 (OsJAR2) are the functional JA-Ile synthases in rice, using recombinant proteins. The expression levels of OsJAR1 and OsJAR2 were induced in response to wounding with the concomitant accumulation of JA-Ile. In contrast, only the expression of OsJAR1 was associated with the accumulation of JA-Ile after blast infection. Our data suggest that these two JA-Ile synthases are differentially involved in the activation of JA signalling in response to wounding and pathogen challenge in rice.

  4. Enriched Pt-Re-Os isotope systematics in plume lavas explained by metasomatic sulfides.

    PubMed

    Luguet, Ambre; Graham Pearson, D; Nowell, Geoff M; Dreher, Scott T; Coggon, Judith A; Spetsius, Zdislav V; Parman, Stephen W

    2008-01-25

    To explain the elevated osmium isotope (186Os-187Os) signatures in oceanic basalts, the possibility of material flux from the metallic core into the crust has been invoked. This hypothesis conflicts with theoretical constraints on Earth's thermal and dynamic history. To test the veracity and uniqueness of elevated 186Os-187Os in tracing core-mantle exchange, we present highly siderophile element analyses of pyroxenites, eclogites plus their sulfides, and new 186Os/188Os measurements on pyroxenites and platinum-rich alloys. Modeling shows that involvement in the mantle source of either bulk pyroxenite or, more likely, metasomatic sulfides derived from either pyroxenite or peridotite melts can explain the 186Os-187Os signatures of oceanic basalts. This removes the requirement for core-mantle exchange and provides an effective mechanism for generating Os isotope diversity in basalt source regions.

  5. The NAC family transcription factor OsNAP confers abiotic stress response through the ABA pathway.

    PubMed

    Chen, Xu; Wang, Yaofeng; Lv, Bo; Li, Jie; Luo, Liqiong; Lu, Songchong; Zhang, Xuan; Ma, Hong; Ming, Feng

    2014-03-01

    Plants respond to environmental stresses by altering gene expression, and several genes have been found to mediate stress-induced expression, but many additional factors are yet to be identified. OsNAP is a member of the NAC transcription factor family; it is localized in the nucleus, and shows transcriptional activator activity in yeast. Analysis of the OsNAP transcript levels in rice showed that this gene was significantly induced by ABA and abiotic stresses, including high salinity, drought and low temperature. Rice plants overexpressing OsNAP did not show growth retardation, but showed a significantly reduced rate of water loss, enhanced tolerance to high salinity, drought and low temperature at the vegetative stage, and improved yield under drought stress at the flowering stage. Microarray analysis of transgenic plants overexpressing OsNAP revealed that many stress-related genes were up-regulated, including OsPP2C06/OsABI2, OsPP2C09, OsPP2C68 and OsSalT, and some genes coding for stress-related transcription factors (OsDREB1A, OsMYB2, OsAP37 and OsAP59). Our data suggest that OsNAP functions as a transcriptional activator that plays a role in mediating abiotic stress responses in rice.

  6. Rice GDP dissociation inhibitor 3 inhibits OsMAPK2 activity through physical interaction.

    PubMed

    Heo, Jae Bok; Yi, Young Byung; Bahk, Jeong Dong

    2011-11-04

    GDP dissociation inhibitor (GDI) plays an essential role in regulating the state of bound nucleotides and subcellular localizations of Rab proteins. In our previous study, we showed that OsGDI3 facilitates the recycling of OsRab11 with a help of OsGAP1. In this study, we show that OsGDI3 complement the yeast sec19-1 mutant, a temperature-sensitive allele of the yeast GDI gene, suggesting that OsGDI3 is a functional ortholog of yeast GDI. To obtain further knowledge on the function of OsGDI3, candidate OsGDI3-interacting proteins were identified by yeast two-hybrid screens. OsMAPK2 is one of OsGDI3 interacting proteins from yeast two-hybrid screens and subject to further analysis. A kinase assay showed that the autophosphorylation activity of OsMAPK2 is inhibited by OsGDI3 in vitro. In addition, ectopic expressions of OsGDI3-in Arabidopsis cause reductions at the level of phosphorylated AtMPK in phosphorylation activity. Taken together, OsGDI3 functions as a negative regulator of OsMAPK2 through modulating its kinase activity.

  7. Redox-induced terpyridyl substitution in the Os(VI)-hydrazido complex, trans-[Os(VI)(tpy)(Cl)(2)(NN(CH(2))(4)O)](2+).

    PubMed

    Huynh, M H; Lee, D G; White, P S; Meyer, T J

    2001-07-30

    Reaction between the Os(VI)-hydrazido complex, trans-[Os(VI)(tpy)(Cl)(2)(NN(CH(2))(4)O)](2+) (tpy = 2,2':6',2"-terpyridine and O(CH(2))(4)N(-) = morpholide), and a series of N- or O-bases gives as products the substituted Os(VI)-hydrazido complexes, trans-[Os(VI)(4'-RNtpy)(Cl)(2)(NN(CH(2))(4)O)](2+) or trans-[Os(VI)(4'-ROtpy)(Cl)(2)(NN(CH(2))(4)O)](2+) (RN(-) = anilide (PhNH(-)); S,S-diphenyl sulfilimide (Ph(2)S=N(-)); benzophenone imide (Ph(2)C=N(-)); piperidide ((CH(2))(5)N(-)); morpholide (O(CH(2))(4)N(-)); ethylamide (EtNH(-)); diethylamide (Et(2)N(-)); and tert-butylamide (t-BuNH(-)) and RO(-) = tert-butoxide (t-BuO(-)) and acetate (MeCO(2)(-)). The rate law for the formation of the morpholide-substituted complex is first order in trans-[Os(VI)(tpy)(Cl)(2)(NN(CH(2))(4)O)](2+) and second order in morpholine with k(morp)(25 degrees C, CH(3)CN) = (2.15 +/- 0.04) x 10(6) M(-)(2) s(-)(1). Possible mechanisms are proposed for substitution at the 4'-position of the tpy ligand by the added nucleophiles. The key features of the suggested mechanisms are the extraordinary electron withdrawing effect of Os(VI) on tpy and the ability of the metal to undergo intramolecular Os(VI) to Os(IV) electron transfer. These substituted Os(VI)-hydrazido complexes can be electrochemically reduced to the corresponding Os(V), Os(IV), and Os(III) forms. The Os-N bond length of 1.778(4) A and Os-N-N angle of 172.5(4) degrees in trans-[Os(VI)(4'-O(CH(2))(4)Ntpy)(Cl)(2)(NN(CH(2))(4)O)](2+) are consistent with sp-hybridization of the alpha-nitrogen of the hydrazido ligand and an Os-N triple bond. The extensive ring substitution chemistry implied for the Os(VI)-hydrazido complexes is discussed.

  8. Comprehensive Analysis of Rice Laccase Gene (OsLAC) Family and Ectopic Expression of OsLAC10 Enhances Tolerance to Copper Stress in Arabidopsis

    PubMed Central

    Liu, Qingquan; Luo, Le; Wang, Xiaoxiao; Shen, Zhenguo; Zheng, Luqing

    2017-01-01

    Laccases are encoded by a multigene family and widely distributed in plant genomes where they play roles oxidizing monolignols to produce higher-order lignin involved in plant development and stress responses. We identified 30 laccase genes (OsLACs) from rice, which can be divided into five subfamilies, mostly expressed during early development of the endosperm, growing roots, and stems. OsLACs can be induced by hormones, salt, drought, and heavy metals stresses. The expression level of OsLAC10 increased 1200-fold after treatment with 20 μM Cu for 12 h. The laccase activities of OsLAC10 were confirmed in an Escherichia coli expression system. Lignin accumulation increased in the roots of Arabidopsis over-expressing OsLAC10 (OsLAC10-OX) compared to wild-type controls. After growth on 1/2 Murashige and Skoog (MS) medium containing toxic levels of Cu for seven days, roots of the OsLAC10-OX lines were significantly longer than those of the wild type. Compared to control plants, the Cu concentration decreased significantly in roots of the OsLAC10-OX line under hydroponic conditions. These results provided insights into the evolutionary expansion and functional divergence of OsLAC family. In addition, OsLAC10 is likely involved in lignin biosynthesis, and reduces the uptake of Cu into roots required for Arabidopsis to develop tolerance to Cu. PMID:28146098

  9. Shape evolution and test of the critical-point symmetry X(5) in 176Os

    NASA Astrophysics Data System (ADS)

    Hao, Xin; Zhu, Li-Hua; Wu, Xiao-Guang; Li, Guang-Sheng; Pan, Bo; Wang, Lie-Lin; Zheng, Yun; Wang, Lei; Li, Xue-Qin; Liu, Ying; Ding, Huai-Bo; Li, Zhong-Yu

    2009-03-01

    The lifetimes of excited states in the yrast band of 176Os have been measured up to I = 20ħ level using the Doppler shift attenuation method. The high-spin states of 176Os were populated via fusion evaporation reaction 152Sm(28Si,4n)176Os at a beam energy of 140 MeV. The results support an X(5) structure for 176Os at low spin. This structure disappears at high spin and shows a symmetry rotor character. The shape change of 176Os is similar to that of 178Os.

  10. Evaluation of the Role of the LysM Receptor-Like Kinase, OsNFR5/OsRLK2 for AM Symbiosis in Rice.

    PubMed

    Miyata, Kana; Hayafune, Masahiro; Kobae, Yoshihiro; Kaku, Hanae; Nishizawa, Yoko; Masuda, Yoshiki; Shibuya, Naoto; Nakagawa, Tomomi

    2016-11-01

    In legume-specific rhizobial symbiosis, host plants perceive rhizobial signal molecules, Nod factors, by a pair of LysM receptor-like kinases, NFR1/LYK3 and NFR5/NFP, and activate symbiotic responses through the downstream signaling components also required for arbuscular mycorrhizal (AM) symbiosis. Recently, the rice NFR1/LYK3 ortholog, OsCERK1, was shown to play crucial roles for AM symbiosis. On the other hand, the roles of the NFR5/NFP ortholog in rice have not been elucidated, while it has been shown that NFR5/NFP orthologs, Parasponia PaNFR5 and tomato SlRLK10, engage in AM symbiosis. OsCERK1 also triggers immune responses in combination with a receptor partner, OsCEBiP, against fungal or bacterial infection, thus regulating opposite responses against symbiotic and pathogenic microbes. However, it has not been elucidated how OsCERK1 switches these opposite functions. Here, we analyzed the function of the rice NFR5/NFP ortholog, OsNFR5/OsRLK2, as a possible candidate of the OsCERK1 partner for symbiotic signaling. Inoculation of AM fungi induced the expression of OsNFR5 in the rice root, and the chimeric receptor consisting of the extracellular domain of LjNFR5 and the intracellular domain of OsNFR5 complemented the Ljnfr5 mutant for rhizobial symbiosis, indicating that the intracellular kinase domain of OsNFR5 could activate symbiotic signaling in Lotus japonicus. Although these data suggested the possible involvement of OsNFR5 in AM symbiosis, osnfr5 knockout mutants were colonized by AM fungi similar to the wild-type rice. These observations suggested several possibilities including the presence of functionally redundant genes other than OsNFR5 or involvement of novel ligands, which do not require OsNFR5 for recognition.

  11. Modification of os calcis bone mineral profiles during bedrest

    NASA Technical Reports Server (NTRS)

    Vogel, J. M.

    1977-01-01

    The mineral content of the left central os calcis was determined using the photon absorptiometric technique modified for the space missions to permit area scanning, and was compared with total body calcium balance changes. The instrument consists of a rectilinear scanner that is programmed by a specially designed control module to move a low energy X-ray emitting radionuclide placed in opposition to a detector to scan the foot which is places between them. The foot is placed in a plexiglas box filled with water to provide tissue equivalence and to compensate for irregularities in thickness of tissue cover that surrounds the bone. The mineral content is obtained from basic attenuation equation.

  12. Search for extremely deformed systems in {sub 182}Os

    SciTech Connect

    Carpenter, M.P.; Chasman, R.R.; Janssens, R.V.F.

    1995-08-01

    We performed an experiment at Gammasphere to search for elongated shapes in the nucleus {sup 182}Os. Recent calculations by R. R. Chasman show that this nucleus is the most promising for finding structures with major to minor axis ratios of 2.2:1 or greater. These calculations include a necking degree of freedom which is thought to be an improvement over past cranked Strutinsky calculations where predictions for extended shapes in Yb and Er nuclei were made. In order to populate {sup 182}Os at spins > 60 h, we utilized the {sup 139}Ba({sup 48}Ca,4n) reaction. The target was made by evaporating {sup 138}Ba onto a 500-{mu}g/cm{sup 2} Au foil, followed by the evaporation of {approximately}250-{mu}g/cm{sup 2} Au onto the exposed side of the Ba. Such a target was necessary since Ba is highly reactive with oxygen. Even after taking this precaution, the target suffered oxidation which adversely effected the quality of our data. The experiment was performed at Gammasphere using the predetermined energy of 220 MeV. A single target was used and the {sup 138}Ba had a thickness of 750 {mu}g/cm{sup 2}. The run lasted four days and {approximately}440 x 10{sup 6} 3-fold and higher Compton-suppressed Ge events were collected. No strong evidence for highly deformed structures was found in this data set. However, it is our belief that the oxygen contamination in our target greatly compromised the outcome of the experiment. Much of the background in our total projection is due to fusion reactions of {sup 48}Ca on oxygen isotopes. The resulting {gamma} rays are highly Doppler broadened and experience larger Doppler shifts relative to the Os residues. Thus, these {gamma} rays are spread out over the entire energy spectrum almost uniformly adding to the background. Our conclusion is that due to target problems, only 150-200 million of the coincidence events can be associated with Os-like residues.

  13. Electrochemical Os-mediated asymmetric dihydroxylation of olefins

    SciTech Connect

    Torii, Sigeru

    1995-12-31

    Recently, the effective chiral ligands for enantioselective dihydroxylation of olefins have intensively been investigated. Among the reported asymmetric dihydroxylation systems, the superiority of a H{sub 2}O/t-BuOH-K{sub 3}Fe(CN){sub 6}/K{sub 2}CO{sub 3} system with chiral ligands, i.e., DHQD and/or DHQ derivatives, has been mentioned. Herein, the authors disclose preliminary studies on the electrochemical Os-catalyzed asymmetric dihyroxylation of olefins with Sharpless` ligands (L*).

  14. Sobre os sistemas de referência celeste

    NASA Astrophysics Data System (ADS)

    Poppe, P. C. R.; Martin, V. A. F.

    2003-02-01

    Apresentamos neste trabalho, algumas discussões sobre os sistemas de referência utilizados em Astronomia. Claramente, não é possível esgotar todo este assunto num único texto, mas esperamos, contudo, que o presente material possa ser apreciado nos cursos de Introdução à Astronomia, que estão cada vez mais presentes nas atuais propostas curriculares das graduações de Física. As discussões pertinentes às "Bases de Referência Celeste", serão apresentadas em um outro trabalho.

  15. Global structure search and physical properties of Os2C

    NASA Astrophysics Data System (ADS)

    Hong, Feng; Lu, Jian; Gao, Heng; Ren, Wei; Xu, Run; Xu, Fei; Ma, Zhongquan; Yan, Yanfa

    2016-09-01

    The crystal structures of Os2C were extensively investigated using the structure search method from the first-principles calculations. In contrast to the P6 3 /mmc phase previously proposed as the ground state at ambient pressure, an energetically favorable structure with space group P-6m2 was found more stable at ambient condition. The structural stabilities of the new phase are confirmed by the phonon dispersion and elastic constants. Further calculations indicate that the newly predicted P-6m2 phase is ultra-incompressible with a high bulk modulus of 387 GPa and has a larger ideal shear strength than the P6 3 /mmc phase.

  16. Re–Os geochronology of the lacustrine Green River Formation: Insights into direct depositional dating of lacustrine successions, Re–Os systematics and paleocontinental weathering

    USGS Publications Warehouse

    Cumming, Vivien M.; Selby, David; Lillis, Paul G.

    2012-01-01

    Lacustrine sedimentary successions provide exceptionally high-resolution records of continental geological processes, responding to tectonic, climatic and magmatic influences. These successions are therefore essential for correlating geological and climatic phenomena across continents and furthermore the globe. Producing accurate geochronological frameworks within lacustrine strata is challenging because the stratigraphy is often bereft of biostratigraphy and directly dateable tuff horizons. The rhenium–osmium (Re–Os) geochronometer is a well-established tool for determining precise and accurate depositional ages of marine organic-rich rocks. Lake systems with stratified water columns are predisposed to the preservation of organic-rich rocks and thus should permit direct Re–Os geochronology of lacustrine strata. We present Re–Os systematics from one of the world's best documented lacustrine systems, the Eocene Green River Formation, providing accurate Re–Os depositional dates that are supported by Ar–Ar and U–Pb ages of intercalated tuff horizons. Precision of the Green River Formation Re–Os dates is controlled by the variation in initial 187Os/188Os and the range of 187Re/188Os ratios, as also documented in marine systems. Controls on uptake and fractionation of Re and Os are considered to relate mainly to depositional setting and the type of organic matter deposited, with the need to further understand the chelating precursors of Re and Os in organic matter highlighted. In addition to geochronology, the Re–Os data records the 187Os/188Os composition of lake water (1.41–1.54) at the time of deposition, giving an insight into continental runoff derived from weathering of the geological hinterland of the Green River Formation. Such insights enable us to evaluate fluctuations in continental climatic, tectonic and magmatic processes and provide the ability for chemostratigraphic correlation combined with direct depositional dates. Furthermore

  17. A first-principle study of Os-based compounds: Electronic structure and vibrational properties

    NASA Astrophysics Data System (ADS)

    Arıkan, N.; Örnek, O.; Charifi, Z.; Baaziz, H.; Uğur, Ş.; Uğur, G.

    2016-09-01

    The electronic structure, elastic, and phonon properties of OsM (M=Hf, Ti, Y and Zr) compounds are studied using first-principles calculations. Elastic constants of OsY and specific heat capacity of OsM (M=Hf, Ti, Y, and Zr) are reported for the first time. The predicted equilibrium lattice constants are in excellent agreement with experiment. The calculated values of bulk moduli are considerably high but are much smaller than that of Osmium, which is around 400 GPa. The phase stability of the OsM (M=Hf, Ti, Y and Zr) compounds were studied by DOS calculations and the results suggest that OsY is unstable in the B2 phase. The brittleness and ductility properties of OsM (M=Hf, Ti, Y and Zr) are determined. OsM (M=Hf, Ti, Y and Zr) compounds are predicted to be ductile materials. The electronic structure and phonon frequency curves of OsM (M=Hf, Ti, Y and Zr) compounds are obtained. The position of Fermi level of these systems was calculated and discussed in terms of the pseudo gaps. The finite and small DOS at the Fermi level 0.335, 0.375, 1.063, and 0.383 electrons/eV for OsHf, OsTi, OsY, and OsZr, respectively, suggest that OsM (M=Hf, Ti, Y and Zr) compounds are weak metals.

  18. Packings of Os layers for the development of L10 order of FePt in nanoscale [Os-FePt]n multilayer systems

    NASA Astrophysics Data System (ADS)

    Su, T. T.; Hsiao, Ching-Hung; Lo, Shen-Chuan; Ouyang, Wen; Li, Tzu-Yuan; Ouyang, H.; Yao, Y. D.

    2013-05-01

    The element osmium (Os), with high melting and boiling points, plays a crucial role in the development of the L10 order for FePt in [Os(5 nm)/FePt(25 nm)]4 and [Os(1 nm)/FePt(5 nm)]20 systems. The large mismatches of lattice constants between Os and FePt, with specific epitaxial relations, induce a great strain in the [Os(5 nm) /FePt(25 nm)]4 system with fixed total thicknesses for the FePt and Os layers. Due to this large strain effect, the L10 order in a FePt structure can be enhanced through an application of stressing along the c axis for the face-centered cubic structure, which results in a higher coercivity. However, a smaller degree of average strain was observed in the 5 nm-thickness FePt system due to the existence of pinholes.

  19. Effects of chemical pressure on the magnetic ground states of the osmate double perovskites SrCaCoOs6 and Ca2CoOsO6

    DOE PAGES

    Morrow, Ryan; Yan, Jiaqiang; McGuire, Michael A.; ...

    2015-09-21

    The magnetic ground state in the double perovskite system Sr2-xCaxCoOsO6 changes from an antiferromagnet (x=0), to a spin glass (x=1), to a ferrimagnet (x=2) as the Ca content increases. Moreover, this crossover is driven by chemical pressure effects that control the relative strength of magnetic exchange interactions. The synthesis, crystal structure, and magnetism of SrCaCoOsO6 and Ca2CoOsO6 are investigated and compared with Sr2CoOsO6. Both compounds adopt a monoclinic crystal structure with rock-salt ordering of Co2+ and Os6+ and a-a-b+ octahedral tilting, but the average Co–O–Os bond angle evolves from 158.0(3) in SrCaCoOsO6 to 150.54(9)° in Ca2CoOsO6 as the smaller Ca2+more » ion replaces Sr2+. And while this change may seem minor, it has a profound effect on the magnetism, changing the magnetic ground state from antiferromagnetic in Sr2CoOsO6 (TN1=108K, TN2=70K), to a spin glass in SrCaCoOsO6 (Tf1=32K, Tf2=13K), to ferrimagnetic in Ca2CoOsO6 (TC=145K). Finally, in the first two compounds the observation of two transitions is consistent with weak coupling between the Co and Os sublattices.« less

  20. The unconventional P-loop NTPase OsYchF1 and its regulator OsGAP1 play opposite roles in salinity stress tolerance.

    PubMed

    Cheung, Ming-Yan; Li, Man-Wah; Yung, Yuk-Lin; Wen, Chao-Qing; Lam, Hon-Ming

    2013-11-01

    YchF proteins are a group of mysterious but ubiquitous unconventional G-proteins found in all kingdoms of life except Archaea. Their functions have been documented in microorganisms, protozoa and human, but those of plant YchF homologues are largely unknown. Our group has previously shown that OsYchF1 and its interacting protein, OsGAP1, play opposite roles in plant defense responses. OsGAP1 was found to stimulate the GTPase/ATPase activities of OsYchF1 and regulate its subcellular localization. In this report, we demonstrate that both OsYchF1 and OsGAP1 are localized mainly in the cytosol under NaCl treatment. The ectopic expression of OsYchF1 in transgenic Arabidopsis thaliana leads to reduced tolerance towards salinity stress, while the ectopic expression of OsGAP1 has the opposite effect. Similar results were also obtained with the Arabidopsis homologues, AtYchF1 and AtGAP1, by using AtGAP1 overexpressors and underexpressors, as well as an AtYchF1-knockdown mutant. OsYchF1 and OsGAP1 also exhibit highly significant effects on salinity-induced oxidative stress tolerance. The expression of OsYchF1 suppresses the anti-oxidation enzymatic activities and increases lipid peroxidation in transgenic Arabidopsis, and leads to the accumulation of reactive oxygen species (ROS) in tobacco BY-2 cells, while the ectopic expression of OsGAP1 has the opposite effects in these two model systems.

  1. Spectroscopic constants and potential energy curves for OsH

    NASA Astrophysics Data System (ADS)

    Benavides-Garcia, M.; Balasubramanian, K.

    1991-11-01

    Complete active space (CASSCF) followed by first-order configuration interaction (FOCI) and second-order CI (SOCI) are carried out on 21 low-lying electronic states of OsH. Spin-orbit effects are investigated using the relativistic CI (RCI) methodology. The ground state of OsH is found to be 4Π symmetry with R e = 1.606 Å, ωe = 2138 cm -1, De = 2.317 eV, and μe = -1.651 D in the absence of spin-orbit interactions, while the ground state is found to be a strong mixture of 4Π( {5}/{2}) and 4Δ( {5}/{2}) including spin-orbit coupling. Potential energy surfaces for 21 low-lying electronic states are reported. Allowed electronic transitions from the ground X4Π and some other low-lying states are predicted. The nature and bonding of the low-lying electronic states are analyzed through Mulliken populations.

  2. Os-186 and Os-187 Enrichments and High-He-3/He-4 sources in the Earth's Mantle: Evidence from Icelandic Picrites

    NASA Technical Reports Server (NTRS)

    Brandon, Alan D.; Graham, David W.; Waight, Tod; Gautason, Bjarni

    2007-01-01

    Picrites from the neovolcanic zones in Iceland display a range in Os-187/Os-188O from 0.1297 to 0.1381 ((gamma)Os = 0.0 to 6.5) and uniform Os-186/Os-188 of 0.1198375+/-32 (2 (sigma)). The value for Os-186/Os-188 is within uncertainty of the present-day value for the primitive upper mantle of 0.1198398+/-16. These Os isotope systematics are best explained by ancient recycled crust or melt enrichment in the mantle source region. If so, then the coupled enrichments displayed in Os-186/Os-188 and Os-187/Os-188 from lavas of other plume systems must result from an independent process, the most viable candidate at present remains core-mantle interaction. While some plumes with high He-3/He-4, such as Hawaii, appear to have been subjected to detectable addition of Os (and possibly He) from the outer core, others such as Iceland do not. A positive correlation between Os-187/Os-188 and He-3/He-4 from 9.6 to 19 RA in Iceland picrites is best modeled as mixtures of 500 Ma or older ancient recycled crust mixed with primitive mantle, creating a hybrid source region that subsequently mixes with the convecting MORB mantle during ascent and melting. This multistage mechanism to explain these isotope systematics is consistent with ancient recycled crust juxtaposed with more primitive, relatively He-rich mantle, in convective isolation from the upper mantle, most likely in the lowermost mantle. This is inconsistent with models that propose random mixing between heterogeneities in the convecting upper mantle as a mechanism to explain the observed isotopic variation in oceanic lavas or models that produce a high He-3/He-4 signature in melt depleted and strongly outgassed, He-poor mantle. Instead these systematics require a deep mantle source to explain the 3He/4He signature in Iceland lavas. The He-3/He-4 of lavas derived from the Iceland plume changed over time, from a maximum of 50 RA at 60 Ma, to approximately 25-27 RA at present. The changes are coupled with distinct

  3. Os-Sr-Nd results from sediments in the Bay of Bengal: Implications for sediment transport and the marine Os record

    NASA Astrophysics Data System (ADS)

    Pierson-Wickmann, Anne-Catherine; Reisberg, Laurie; France-Lanord, Christian; Kudrass, Herman R.

    2001-08-01

    Sr, Nd, and Os isotopic data are presented for sediments from diverse locations in the Bay of Bengal. These data allow the samples to be divided into three groups, related to their sedimentary contexts. The first group, mainly composed of sediments from the shelf off Bangladesh and the currently active fan, has Sr and Nd characteristics consistent with a dominantly Himalayan source. Their 187Os/188Os ratios (˜1.2-1.5) show that the average detrital material delivered by the Ganga-Brahmaputra (G-B) river system is not unusually radiogenic. A large difference in 187Os/188Os ratio exists between these Bengal Fan sediments and Ganga bedloads (187Os/188Os ˜2.5, Pierson-Wickmann et al. [2000]). This difference mainly reflects addition of a less radiogenic Brahmaputra component, though mineralogical sorting and loss of radiogenic Os during transport may also play some role. The second sample group contains sediments from elsewhere in the Bay, particularly those located on the continental slope. They display Os isotopic compositions (0.99-1.11) similar to that of present seawater and higher Os and Re concentrations. These characteristics suggest the presence of a large hydrogenous contribution, consistent with the lower sedimentation rate of these samples. Sr and Nd ratios indicate that a significant fraction of these sediments is derived from erosion of non-Himalayan sources, such as the Indo-Burman range. These observations could be explained by the deflection of sediments from the G-B river system by westward currents in the head of the Bay. The third group contains only one sample, but shows that in addition to a Himalayan source, sediment discharge from Sri Lanka may influence the detrital component in the distal part of the fan. The similarity between the isotopic compositions of the group I R/V Sonne samples and those of Ocean Drilling Program Leg 116 [France-Lanord et al., 1993; Reisberg et al., 1997] suggests that the material eroding in the Himalayas has been

  4. OsCUL3a Negatively Regulates Cell Death and Immunity by Degrading OsNPR1 in Rice[OPEN

    PubMed Central

    Zhang, Yingxin; Yu, Ning; Zhao, Chunde; Zhan, Xiaodeng; Wu, Weixun; Chen, Daibo; Wei, Xiangjin; Cheng, Shihua; Cao, Liyong

    2017-01-01

    Cullin3-based RING E3 ubiquitin ligases (CRL3), composed of Cullin3 (CUL3), RBX1, and BTB proteins, are involved in plant immunity, but the function of CUL3 in the process is largely unknown. Here, we show that rice (Oryza sativa) OsCUL3a is important for the regulation of cell death and immunity. The rice lesion mimic mutant oscul3a displays a significant increase in the accumulation of flg22- and chitin-induced reactive oxygen species, and in pathogenesis-related gene expression as well as resistance to Magnaporthe oryzae and Xanthomonas oryzae pv oryzae. We cloned the OsCUL3a gene via a map-based strategy and found that the lesion mimic phenotype of oscul3a is associated with the early termination of OsCUL3a protein. Interaction assays showed that OsCUL3a interacts with both OsRBX1a and OsRBX1b to form a multisubunit CRL in rice. Strikingly, OsCUL3a interacts with and degrades OsNPR1, which acts as a positive regulator of cell death in rice. Accumulation of OsNPR1 protein is greater in the oscul3a mutant than in the wild type. Furthermore, the oscul3a osnpr1 double mutant does not exhibit the lesion mimic phenotype of the oscul3a mutant. Our data demonstrate that OsCUL3a negatively regulates cell death and immunity by degrading OsNPR1 in rice. PMID:28100706

  5. Effects of mother lode-type gold mineralization on 187Os/188Os and platinum group element concentrations in peridotite: Alleghany District, California

    USGS Publications Warehouse

    Walker, R.J.; Böhlke, J.K.; McDonough, W.F.; Li, J.

    2007-01-01

    Osmium isotope compositions and concentrations of Re, platinum group elements (PGE), and Au were determined for host peridotites (serpentinites and barzburgites) and hydrothermally altered ultramafic wall rocks associated with Mother Lode-type hydrothermal gold-quartz vein mineralization in the Alleghany district, California. The host peridotites have Os isotope compositions and Re, PGE, and Au abundances typical of the upper mantle at their presumed formation age during the late Proterozoic or early Paleozoic. The hydrothermally altered rocks have highly variable initial Os isotope compositions with ??os, values (% deviation of 187OS/188OS from the chondritic average calculated for the approx. 120 Ma time of mineralization) ranging from -1.4 to -8.3. The lowest Os isotope compositions are consistent with Re depletion of a chondritic source (e.g., the upper mantle) at ca. 1.6 Ga. Most of the altered samples are enriched in Au and have depleted and fractionated abundances of Re and PGE relative to their precursor peridotites. Geoehemical characteristics of the altered samples suggest that Re and some PGE were variably removed from the ultramafic rocks during the mineralization event. In addition to Re, the Pt and Pd abundances of the most intensely altered rocks appear to have been most affected by mineralization. The 187Os-depleted isotopic compositions of some altered rocks are interpreted to be a result of preferential 187Os loss via destruction of Re-rich phases during the event. For these rocks, Os evidently is not a useful tracer of the mineralizing fluids. The results do, however, provide evidence for differential mobility of these elements, and mobility of 187Os relative to the initial bulk Os isotope composition during hydrothermal metasomatic alteration of ultramafic rocks. ?? 2007 Society of Economic Geologists, Inc.

  6. Overexpression of Rice Glutaredoxin OsGrx_C7 and OsGrx_C2.1 Reduces Intracellular Arsenic Accumulation and Increases Tolerance in Arabidopsis thaliana

    PubMed Central

    Verma, Pankaj K.; Verma, Shikha; Pande, Veena; Mallick, Shekhar; Deo Tripathi, Rudra; Dhankher, Om P.; Chakrabarty, Debasis

    2016-01-01

    Glutaredoxins (Grxs) are a family of small multifunctional proteins involved in various cellular functions, including redox regulation and protection under oxidative stress. Despite the high number of Grx genes in plant genomes (48 Grxs in rice), the biological functions and physiological roles of most of them remain unknown. Here, the functional characterization of the two arsenic-responsive rice Grx family proteins, OsGrx_C7 and OsGrx_C2.1 are reported. Over-expression of OsGrx_C7 and OsGrx_C2.1 in transgenic Arabidopsis thaliana conferred arsenic (As) tolerance as reflected by germination, root growth assay, and whole plant growth. Also, the transgenic expression of OsGrxs displayed significantly reduced As accumulation in A. thaliana seeds and shoot tissues compared to WT plants during both AsIII and AsV stress. Thus, OsGrx_C7 and OsGrx_C2.1 seem to be an important determinant of As-stress response in plants. OsGrx_C7 and OsGrx_C2.1 transgenic showed to maintain intracellular GSH pool and involved in lowering AsIII accumulation either by extrusion or reducing uptake by altering the transcript of A. thaliana AtNIPs. Overall, OsGrx_C7 and OsGrx_C2.1 may represent a Grx family protein involved in As stress response and may allow a better understanding of the As induced stress pathways and the design of strategies for the improvement of stress tolerance as well as decreased As content in crops. PMID:27313586

  7. The Double-System Architecture for Trusted OS

    NASA Astrophysics Data System (ADS)

    Zhao, Yong; Li, Yu; Zhan, Jing

    With the development of computer science and technology, current secure operating systems failed to respond to many new security challenges. Trusted operating system (TOS) is proposed to try to solve these problems. However, there are no mature, unified architectures for the TOS yet, since most of them cannot make clear of the relationship between security mechanism and the trusted mechanism. Therefore, this paper proposes a double-system architecture (DSA) for the TOS to solve the problem. The DSA is composed of the Trusted System (TS) and the Security System (SS). We constructed the TS by establishing a trusted environment and realized related SS. Furthermore, we proposed the Trusted Information Channel (TIC) to protect the information flow between TS and SS. In a word, the double system architecture we proposed can provide reliable protection for the OS through the SS with the supports provided by the TS.

  8. Multiple mixed-valence behavior in trans,trans-[(tpy)(Cl)2Os(III)(mu-1,3-N3)Os(III)(Cl)2(tpy)]+. An azido bridge from the reaction between trans-[Os(VI)(tpy)(Cl)2(N)]+ and NH3.

    PubMed

    Huynh, My Hang V; Meyer, Thomas J; Labouriau, Andrea; Morris, David E; White, Peter S

    2003-03-12

    Reaction between the Os(VI)-nitrido complex, trans-[OsVI(tpy)(Cl)2(N)]PF6 (tpy = 2,2':6',2' '-terpyridine), and ammonia (NH3) under N2 in dry CH3CN gives the mu-1,3-azido bridged [OsII-N3-OsII]- dimer, trans,trans-NH4[(tpy)(Cl)2OsII(N3)OsII(Cl)2(tpy)]. It undergoes air oxidation to give the [OsIII-N3-OsIII]+ analogue, trans,trans-[(tpy)(Cl)2OsIII(N3)OsIII(Cl)2(tpy)]PF6 ([OsIII-N3-OsIII]PF6), which has been isolated and characterized. The structural formulation as a mu-1,3-N3 bridged complex has been established by infrared and 15N NMR measurements on the 15N-labeled forms, [OsIII-14N=15N=14N-OsIII]+, [OsIII-15N=14N=15N-OsIII]+, and [OsIII-15N=15N=15N-OsIII]+. Cyclic voltammetric measurements in 0.2 M Bu4NPF6/CH3CN reveal the existence of five chemically reversible waves from 1.40 to -0.12 V for couples ranging from OsV-OsIV/OsIV-OsIV to OsIII-OsII/OsII-OsII. DeltaE1/2 values for couples adjacent to the three mixed-valence forms are 0.19 V for OsIII-OsII, 0.52 V for OsIV-OsIII, and >0.71 V for OsV-OsIV. In CH3CN at 60 degrees C, [OsIII-N3-OsIII]+ undergoes a [2 + 3] cycloaddition with CH3CN at the mu-N3- bridge followed by a solvolysis to give trans-[OsIII(tpy)(Cl)2(5-MeCN4)] and trans-[OsIII(tpy)(Cl)2(NCCH3)]PF6.

  9. Synthesis, crystal structures, and magnetic properties of double perovskites SrLaNiOsO6 and BaLaNiOsO6

    NASA Astrophysics Data System (ADS)

    Feng, Hai L.; Schnelle, Walter; Tjeng, Liu Hao; Jansen, Martin

    2016-10-01

    New double perovskite oxides SrLaNiOsO6 and BaLaNiOsO6 were synthesized by solid state reactions from the respective binary metal oxides, and their crystal structures and magnetic properties were characterized. At room temperature SrLaNiOsO6 and BaLaNiOsO6 crystallize in ordered double perovskite structures with space groups of P21/n (monoclinic) and I4/m (tetragonal), respectively. They are electrically semiconducting with an activation energy of ≈0.35 eV. Specific heat and magnetic measurements indicate that SrLaNiOsO6 shows predominantly antiferromagnetic correlations and displays antiferromagnetic transition around 60 K. However, for the isoelectronic BaLaNiOsO6 ferromagnetic correlations are predominant and there is no clear feature of a magnetic transition detectable. The remarkable change in magnetic properties of ALaNiOsO6 (A = Sr and Ba) can be related to the degree of structure distortions, i.e. the bending of the O-B-O (B = Ni,Os) links.

  10. The role of OsMSH4 in male and female gamete development in rice meiosis

    PubMed Central

    Wang, Chaolong; Wang, Yang; Cheng, Zhijun; Zhao, Zhigang; Chen, Jun; Sheng, Peike; Yu, Yang; Ma, Weiwei; Duan, Erchao; Wu, Fuqing; Liu, Linglong; Qin, Ruizhen; Zhang, Xin; Guo, Xiuping; Wang, Jiulin; Jiang, Ling; Wan, Jianmin

    2016-01-01

    Meiosis is essential for gametogenesis in sexual reproduction in rice (Oryza sativa L.). We identified a MutS-homolog (MSH) family gene OsMSH4 in a trisomic plant. Cytological analysis showed that developments of both pollen and embryo sacs in an Osmsh4 mutant were blocked due to defective chromosome pairing. Compared with the wild type, the Osmsh4 mutant displayed a significant ~21.9% reduction in chiasma frequency, which followed a Poisson distribution, suggesting that class I crossover formation in the mutant was impaired. Temporal and spatial expression pattern analyses showed that OsMSH4 was preferentially expressed in meiocytes during their meiosis, indicating a critical role in gametogenesis. Subcellular localization showed that OsMSH4–green fluorescent protein was predominantly located in the nucleus. OsMSH4 could interact with another MSH member (OsMSH5) through the N-terminus and C-terminus, respectively. Direct physical interaction between OsMSH5, OsRPA1a, OsRPA2b, OsRPA1c, and OsRPA2c was identified by yeast two-hybrid assays and further validated by pull-down assays. Our results supported the conclusion that the OsMSH4/5 heterodimer plays a key role in regulation of crossover formation during rice meiosis by interaction with the RPA complex. PMID:26712826

  11. Over-expression of OsDREB genes lead to enhanced drought tolerance in rice.

    PubMed

    Chen, Jian-Qiang; Meng, Xiu-Ping; Zhang, Yun; Xia, Mian; Wang, Xi-Ping

    2008-12-01

    The DREB transcription factors, which specifically interact with C-repeat/DRE (A/GCCGAC), play an important role in plant abiotic stress tolerance by controlling the expression of many cold or/and drought-inducible genes in an ABA-independent pathway. We have isolated three novel rice DREB genes, OsDREB1E, OsDREB1G, and OsDREB2B, which are homologous to Arabidopsis DREB genes. The yeast one-hybrid assay indicated that OsDREB1E, OsDREB1G, and OsDREB2B can specifically bind to the C-repeat/DRE element. To elucidate the function of respective OsDREB genes, we have stably introduced these to rice by Agrobacterium-mediated transformation. Transgenic rice plants analysis revealed that over-expression of OsDREB1G and OsDREB2B in rice significantly improved their tolerance to water deficit stress, while over-expression of OsDREB1E could only slightly improved the tolerance to water deficit stress, suggesting that the OsDREBs might participate in the stress response pathway in different manners.

  12. OsAM1 is required for leptotene-zygotene transition in rice

    PubMed Central

    Che, Lixiao; Tang, Ding; Wang, Kejian; Wang, Mo; Zhu, Keming; Yu, Hengxiu; Gu, Minghong; Cheng, Zhukuan

    2011-01-01

    The events occurring at the onset of meiosis have not been fully elucidated. In the present study, OsAM1 was identified in rice (Oryza sativa L.) by map-based cloning. OsAM1, a homolog of Arabidopsis SWI1 and maize AM1, encodes a protein with a coiled-coil domain in its central region. In the Osam1 mutant, pollen mother cells are arrested at leptotene, showing that OsAM1 is required for the leptotene-zygotene transition. Immunocytological analysis revealed that OsAM1 exists as foci in early prophase I meiocytes. Very faint OsREC8 foci persisted in the Osam1 mutant, indicating that OsAM1 is not required for the initial meiotic recruitment of OsREC8. In the absence of OsAM1, many other critical meiotic components, including PAIR2, ZEP1 and OsMER3, could not be correctly installed onto chromosomes. In contrast, in pair2, Osmer3 and zep1 mutants, OsAM1 could be loaded normally, suggesting that OsAM1 plays a fundamental role in building the proper chromosome structure at the beginning of meiosis. PMID:21221128

  13. Phytochrome B Negatively Affects Cold Tolerance by Regulating OsDREB1 Gene Expression through Phytochrome Interacting Factor-Like Protein OsPIL16 in Rice

    PubMed Central

    He, Yanan; Li, Yaping; Cui, Lixin; Xie, Lixia; Zheng, Chongke; Zhou, Guanhua; Zhou, Jinjun; Xie, Xianzhi

    2016-01-01

    Cross talk between light signaling and cold signaling has been elucidated in the model plant Arabidopsis and tomato, but little is known about their relationship in rice. Here, we report that phytochrome B (phyB) mutants exhibit improved cold tolerance compared with wild type (WT) rice (Oryza sativa L. cv. Nipponbare). The phyB mutants had a lower electrolyte leakage index and malondialdehyde concentration than the WT, suggesting that they had greater cell membrane integrity and less lipid peroxidation. Real-time PCR analysis revealed that the expression levels of dehydration-responsive element binding protein 1 (OsDREB1) family genes, which functions in the cold stress response in rice, were increased in the phyB mutant under normal and cold stress conditions. PIFs are central players in phytochrome-mediated light signaling networks. To explore the relationship between rice PIFs and OsDREB1 gene expression, we produced overexpression lines of rice PIF genes. OsDREB1 family genes were up-regulated in OsPIL16-overexpression lines, which had improved cold tolerance relative to the WT. Chromatin immunoprecipitation (ChIP)-qPCR assay revealed that OsPIL16 can bind to the N-box region of OsDREB1B promoter. Expression pattern analyses revealed that OsPIL16 transcripts were induced by cold stress and was significantly higher in the phyB mutant than in the WT. Moreover, yeast two-hybrid assay showed that OsPIL16 can bind to rice PHYB. Based on these results, we propose that phyB deficiency positively regulates OsDREB1 expression through OsPIL16 to enhance cell membrane integrity and to reduce the malondialdehyde concentration, resulting in the improved cold tolerance of the phyB mutants. PMID:28083003

  14. Hyponatremia and Fractures: Findings From the MrOS Study.

    PubMed

    Jamal, Sophie A; Arampatzis, Spyridon; Harrison, Stephanie Litwack; Bucur, Roxana C; Ensrud, Kristine; Orwoll, Eric S; Bauer, Douglas C

    2015-06-01

    Hyponatremia may be a risk factor for fracture. To determine the relationship between hyponatremia and fracture we conducted cross-sectional and longitudinal analyses using data from the Osteoporotic Fractures in Men (MrOS) study. The MrOS study enrolled 5122 community dwelling men aged ≥65 years from six centers across the United States. We excluded men taking bisphosphonates, those with unknown medication history, those without serum sodium measures, or those with out of range assays for serum sodium. Serum sodium was measured at study entry. Subjects were followed for fractures (nonspine [including hip], hip, incident morphometric, and prevalent morphometric) for up to 9 years. We used Cox proportional hazards models to analyze the association between serum sodium levels (<135 mmol/L versus ≥135 mmol/L) and risk of nonspine and hip fractures, with results presented as hazard ratios (HRs) and 95% confidence intervals (CIs). We examined the association between morphometric vertebral fractures and serum sodium using logistic regression models, presented as odds ratios (ORs) and 95% CI. Hyponatremia was observed in 64 men (1.2% of the cohort). After adjusting for age, BMI, study center, and other covariates, we found that, compared to men with serum sodium ≥135 mmol/L, those with serum sodium <135 mmol/L, had an increased risk of hip fracture (HR = 3.04; 95% CI, 1.37 to 6.75), prevalent morphometric spine fracture (OR = 2.46; 95% CI, 1.22 to 4.95), and incident morphometric spine fracture (OR = 3.53; 95% CI, 1.35 to 9.19), but not nonspine fracture (OR = 1.44; 95% CI, 0.85 to 2.44). Adjusting for bone mineral density (BMD) did not change our findings. Our data show that hyponatremia is associated with up to a doubling in the risk of hip and morphometric spine fractures, independent of BMD. Further studies, to determine how hyponatremia causes fractures and if correction of hyponatremia decreases fractures, are needed.

  15. Fermi-surface topologies and low-temperature phases of the filled skutterudite compounds CeOs4Sb12 and NdOs4Sb12

    NASA Astrophysics Data System (ADS)

    Ho, Pei Chun; Singleton, John; Goddard, Paul A.; Balakirev, Fedor F.; Chikara, Shalinee; Yanagisawa, Tatsuya; Maple, M. Brian; Shrekenhamer, David B.; Lee, Xia; Thomas, Avraham T.

    2016-11-01

    MHz conductivity, torque magnetometer, and magnetization measurements are reported on single crystals of CeOs4Sb12 and NdOs4Sb12 using temperatures down to 0.5 K and magnetic fields of up to 60 tesla. The field-orientation dependence of the de Haas-van Alphen and Shubnikov-de Haas oscillations is deduced by rotating the samples about the [010 ] and [0 1 ¯1 ] directions. The results indicate that NdOs4Sb12 has a similar Fermi surface topology to that of the unusual superconductor PrOs4Sb12 , but with significantly smaller effective masses, supporting the importance of local phonon modes in contributing to the low-temperature heat capacity of NdOs4Sb12 . By contrast, CeOs4Sb12 undergoes a field-induced transition from an unusual semimetal into a high-field, high-temperature state characterized by a single, almost spherical Fermi-surface section. The behavior of the phase boundary and comparisons with models of the band structure lead us to propose that the field-induced phase transition in CeOs4Sb12 is similar in origin to the well-known α -γ transition in Ce and its alloys.

  16. Applications of the 190Pt-186Os isotope system to geochemistry and cosmochemistry

    USGS Publications Warehouse

    Walker, R.J.; Morgan, J.W.; Beary, E.S.; Smoliar, M.I.; Czamanske, G.K.; Horan, M.F.

    1997-01-01

    Platinum is fractionated from osmium primarily as a consequence of processes involving sulfide and metal crystallization. Consequently, the 190Pt-186Os isotope system (190Pt ??? 186Os + ??) shows promise for dating some types of magmatic sulfide ores and evolved iron meteorites. The first 190Pt-186Os isochrons are presented here for ores from the ca. 251 Ma Noril'sk, Siberia plume, and for group IIAB magmatic iron meteorites. Given the known age of the Noril'sk system, a decay constant for 190Pt is determined to be 1.542 ?? 10-12a-1, with ??1% uncertainty. The isochron generated for the IIAB irons is consistent with this decay constant and the known age of the group. The 186Os/188Os ratios of presumably young, mantle-derived osmiridiums and also the carbonaceous chondrite Allende were measured to high-precision to constrain the composition of the modern upper mantle. These compositions overlap, indicating that the upper mantle is chondritic within the level of resolution now available. Our best estimate for this 186Os/188Os ratio is 0.119834 ?? 2 (2??M). The 190Pt/186Os ratios determined for six enstatite chondrites average 0.001659 ?? 75, which is very similar to published values for carbonaceous chondrites. Using this ratio and the presumed composition of the modern upper mantle and chondrites, a solar system initial 186Os/188Os ratio of 0.119820 is calculated. In comparison to the modern upper mantle composition, the 186Os/188Os ratio of the Noril'sk plume was approximately 0.012% enriched in 186Os. Possible reasons for this heterogeneity include the recycling of Pt-rich crust into the mantle source of the plume and derivation of the osmium from the outer core. Derivation of the osmium from the outer core is our favored model. Copyright ?? 1997 Elsevier Science Ltd.

  17. Interactions of OsMADS1 with Floral Homeotic Genes in Rice Flower Development.

    PubMed

    Hu, Yun; Liang, Wanqi; Yin, Changsong; Yang, Xuelian; Ping, Baozhe; Li, Anxue; Jia, Ru; Chen, Mingjiao; Luo, Zhijing; Cai, Qiang; Zhao, Xiangxiang; Zhang, Dabing; Yuan, Zheng

    2015-09-01

    During reproductive development, rice plants develop unique flower organs which determine the final grain yield. OsMADS1, one of SEPALLATA-like MADS-box genes, has been unraveled to play critical roles in rice floral organ identity specification and floral meristem determinacy. However, the molecular mechanisms underlying interactions of OsMADS1 with other floral homeotic genes in regulating flower development remains largely elusive. In this work, we studied the genetic interactions of OsMADS1 with B-, C-, and D-class genes along with physical interactions among their proteins. We show that the physical and genetic interactions between OsMADS1 and OsMADS3 are essential for floral meristem activity maintenance and organ identity specification; while OsMADS1 physically and genetically interacts with OsMADS58 in regulating floral meristem determinacy and suppressing spikelet meristem reversion. We provided important genetic evidence to support the neofunctionalization of two rice C-class genes (OsMADS3 and OsMADS58) during flower development. Gene expression profiling and quantitative RT-PCR analyses further revealed that OsMADS1 affects the expression of many genes involved in floral identity and hormone signaling, and chromatin immunoprecipitation (ChIP)-PCR assay further demonstrated that OsMADS17 is a direct target gene of OsMADS1. Taken together, these results reveal that OsMADS1 has diversified regulatory functions in specifying rice floral organ and meristem identity, probably through its genetic and physical interactions with different floral homeotic regulators.

  18. Crystal growth, structural transitions, and magnetic properties of the fluorite-related osmates: Sm3OsO7, Eu3OsO7, and Gd3OsO7.

    PubMed

    Gemmill, William R; Smith, Mark D; Mozharivsky, Yurij A; Miller, Gordon J; zur Loye, Hans-Conrad

    2005-10-03

    The Ln3OsO7 (Ln = Sm, Eu, Gd) compounds were grown as single crystals from molten hydroxide fluxes. At temperatures above 235, 330, and 430 K, respectively, the Ln3OsO7 (Ln = Sm, Eu, Gd) compounds exist in the orthorhombic space group Cmcm. When they are cooled below these temperatures, the compounds undergo a structural phase transition from space group Cmcm to P2(1)nb. The structure transition results in a loss of lattice centering, a doubling of the b axis, a distortion of the vertex-shared Os-O chains, and a reduction in the coordination of one of the rare earth cations from 8-fold to 7-fold. Sm3OsO7 and Eu3OsO7 exhibit complex magnetic behavior below about 50 K, and Gd3OsO7 shows a ferromagnetic-like order at 34 K in applied fields of less than 10 kG.

  19. OsBRI1 Activates BR Signaling by Preventing Binding between the TPR and Kinase Domains of OsBSK3 via Phosphorylation1

    PubMed Central

    Wang, Xiaolong; Zhao, Zhiying; Wang, Ruiju; Huang, Xiahe; Zhu, Yali; Yuan, Li; Wang, Yingchun; Burlingame, Alma L.; Gao, Yingjie

    2016-01-01

    Many plant receptor kinases transduce signals through receptor-like cytoplasmic kinases (RLCKs); however, the molecular mechanisms that create an effective on-off switch are unknown. The receptor kinase BR INSENSITIVE1 (BRI1) transduces brassinosteroid (BR) signal by phosphorylating members of the BR-signaling kinase (BSK) family of RLCKs, which contain a kinase domain and a C-terminal tetratricopeptide repeat (TPR) domain. Here, we show that the BR signaling function of BSKs is conserved in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) and that the TPR domain of BSKs functions as a “phospho-switchable” autoregulatory domain to control BSKs’ activity. Genetic studies revealed that OsBSK3 is a positive regulator of BR signaling in rice, while in vivo and in vitro assays demonstrated that OsBRI1 interacts directly with and phosphorylates OsBSK3. The TPR domain of OsBSK3, which interacts directly with the protein’s kinase domain, serves as an autoinhibitory domain to prevent OsBSK3 from interacting with bri1-SUPPRESSOR1 (BSU1). Phosphorylation of OsBSK3 by OsBRI1 disrupts the interaction between its TPR and kinase domains, thereby increasing the binding between OsBSK3’s kinase domain and BSU1. Our results not only demonstrate that OsBSK3 plays a conserved role in regulating BR signaling in rice, but also provide insight into the molecular mechanism by which BSK family proteins are inhibited under basal conditions but switched on by the upstream receptor kinase BRI1. PMID:26697897

  20. Redox chemistry of morpholine-based Os(VI)-hydrazido complexes: trans-[Os(VI)(tpy)(Cl)2(NN(CH2)4O)](2+).

    PubMed

    Huynh, M H; White, P S; Meyer, T J

    2001-09-24

    The oxidations of benzyl alcohol, PPh3, and the sulfides (SEt2 and SPh2) (Ph = phenyl and Et = ethyl) by the Os(VI)-hydrazido complex trans-[Os(VI)(tpy)(Cl)2(NN(CH2)4O)](2+) (tpy = 2,2':6',2' '-terpyridine and O(CH2)4N(-) = morpholide) have been investigated in CH3CN solution by UV-visible monitoring and product analysis by gas chromatography-mass spectrometry. For benzyl alcohol and the sulfides, the rate law for the formation of the Os(V)-hydrazido complex, trans-[Os(V)(tpy)(Cl)2(NN(CH2)4O)](+), is first order in both trans-[Os(VI)(tpy)(Cl)2(NN(CH2)4O)](2+) and reductant, with k(benzyl) (25.0 +/- 0.1 degrees C, CH3CN) = (1.80 +/- 0.07) x 10(-4) M(-1) s(-1), k(SEt2) = (1.33 +/- 0.02) x 10(-1) M(-1) s(-1), and k(SPh2) = (1.12 +/- 0.05) x 10(-1) M(-1) s(-1). Reduction of trans-[Os(VI)(tpy)(Cl)2(NN(CH2)4O)](2+) by PPh3 is rapid and accompanied by isomerization and solvolysis to give the Os(IV)-hydrazido product, cis-[Os(IV)(tpy)(NCCH3)2(NN(CH2)4O)](2+), and OPPh3. This reaction presumably occurs by net double Cl-atom transfer to PPh3 to give Cl2PPh3 that subsequently undergoes hydrolysis by trace H2O to give the final product, OPPh3. In the X-ray crystal structure of the Os(IV)-hydrazido complex, the Os-N-N angle of 130.9(5) degrees and the Os-N bond length of 1.971(7) A are consistent with an Os-N double bond.

  1. Behavior of Re and Os during contact between an aqueous solution and oil: Consequences for the application of the Re-Os geochronometer to petroleum

    NASA Astrophysics Data System (ADS)

    Mahdaoui, Fatima; Michels, Raymond; Reisberg, Laurie; Pujol, Magali; Poirier, Yannick

    2015-06-01

    Several recent studies have raised the exciting possibility that oils can be dated using the Re-Os radioisotope system. However the exact nature of the events dated by this technique often remains unclear. Geochronologic interpretation of Re-Os data for oils is hampered by our limited knowledge of how these metals behave in petroleum systems. In particular, it is difficult to understand how isotopic homogenization, an essential prerequisite for the development of an isochronal relationship, can be achieved at the scale of a petroleum basin. The mechanisms capable of fractionating the Re/Os ratio in a suite of oils are also poorly understood. For this reason, we have performed an experimental study aimed at investigating the behavior of Re and Os during a particularly widespread phenomenon in petroleum systems, the interaction of formation waters with oils during migration. Contact experiments between natural oils and aqueous solutions enriched in Re and/or Os were carried out for varying lengths of time (6 h to 5 months), at different temperatures (25-150 °C), over a wide range of metal concentrations in the enriched solution (0.001-100 μg/g for Re; 1 and 10 ng/g for Os). In addition, the effect of oil composition on Re-Os exchange at the water-oil interface was examined by testing two oils with very different properties. All of our results demonstrate that Re and Os are transferred massively and very rapidly from the aqueous solution to the organic phase. This is true regardless of temperature or oil composition. It is also true for a very wide range of metal concentrations in the aqueous solution, up to an apparent saturation level that exceeds natural concentrations in oils by several orders of magnitude. Given the efficiency of Re and Os transfer from water to oil demonstrated here, and assuming that our findings are applicable to natural conditions, water/oil ratios of only about 250 would be needed to explain the Re and Os contents of most oils, based on

  2. Reversible interconversion between a nitrido complex of Os(VI) and an ammino complex of osmium(II)

    SciTech Connect

    Pipes, D.W.; Bakir, M.; Vitols, S.E.; Meyer, T.J. ); Hodgson, D.J. )

    1990-07-04

    The reaction between (N(n-Bu){sub 4})(Os(N)(X){sub 4}) (X = Cl, Br) and 2,2{prime}:6{prime},2{double prime}-terpyridine (tpy) in acetone under reflux gave the salts (Os(N)(typ)(X){sub 2})X. The X-ray crystal structure of (Os(N)(tpy)(Cl){sub 2})Cl showed that the chloride ligands occupy mutually trans axial positions relative to the nitrido ligand. Reduction potentials were measured or estimated at pH = 3 for the intermediate Os(VI/V), Os(V/IV), Os(IV/III), and Os(III/II) couples. From those measurements, it was shown that the Os(V) intermediate, (Os{sup V}(N)(tpy)(Cl){sub 2}), is both a powerful oxidant and a strong reductant, highly unstable with respect to disproportionation into Os(VI) and Os(IV).

  3. Recombinant Expression and Characterization of the Cytoplasmic Rice β-Glucosidase Os1BGlu4

    PubMed Central

    Rouyi, Chen; Baiya, Supaporn; Lee, Sang-Kyu; Mahong, Bancha; Jeon, Jong-Seong; Ketudat-Cairns, James R.; Ketudat-Cairns, Mariena

    2014-01-01

    The Os1BGlu4 β-glucosidase is the only glycoside hydrolase family 1 member in rice that is predicted to be localized in the cytoplasm. To characterize the biochemical function of rice Os1BGlu4, the Os1bglu4 cDNA was cloned and used to express a thioredoxin fusion protein in Escherichia coli. After removal of the tag, the purified recombinant Os1BGlu4 (rOs1BGlu4) exhibited an optimum pH of 6.5, which is consistent with Os1BGlu4's cytoplasmic localization. Fluorescence microscopy of maize protoplasts and tobacco leaf cells expressing green fluorescent protein-tagged Os1BGlu4 confirmed the cytoplasmic localization. Purified rOs1BGlu4 can hydrolyze p-nitrophenyl (pNP)-β-d-glucoside (pNPGlc) efficiently (kcat/Km  =  17.9 mM−1·s−1), and hydrolyzes pNP-β-d-fucopyranoside with about 50% the efficiency of the pNPGlc. Among natural substrates tested, rOs1BGlu4 efficiently hydrolyzed β-(1,3)-linked oligosaccharides of degree of polymerization (DP) 2–3, and β-(1,4)-linked oligosaccharide of DP 3–4, and hydrolysis of salicin, esculin and p-coumaryl alcohol was also detected. Analysis of the hydrolysis of pNP-β-cellobioside showed that the initial hydrolysis was between the two glucose molecules, and suggested rOs1BGlu4 transglucosylates this substrate. At 10 mM pNPGlc concentration, rOs1BGlu4 can transfer the glucosyl group of pNPGlc to ethanol and pNPGlc. This transglycosylation activity suggests the potential use of Os1BGlu4 for pNP-oligosaccharide and alkyl glycosides synthesis. PMID:24802508

  4. Precise Re-Os age and low initial 187Os/188Os for latest Permian black shales from the mid-Norwegian shelf herald the Permo-Triassic extinction

    NASA Astrophysics Data System (ADS)

    Georgiev, S.; Stein, H. J.; Hannah, J. L.; Bingen, B.; Xu, G.; Yang, G.; Zimmerman, A.; Weiss, H. M.

    2009-12-01

    The Permo-Triassic boundary records a profound chemical transition and the largest mass extinction in Earth history. Understanding the causal events requires detailed examination of bio/chemo stratigraphic changes precisely pinned in absolute time. Here we report Re-Os isotopic results for well-defined black shale horizons within the Upper Permian marine succession from the Mid-Norwegian shelf: (1) a high-precision Re-Os depositional age and (2) a record of the changes in the Os isotopic composition of seawater at the onset of the Permo-Triassic extinction. Drill core penetrating a Permian-Triassic turbidite succession on the Trøndelag platform, offshore mid-Norway, provided nine organic rich (~3.5% TOC) shale samples over a ca. 30 cm interval. The Re-Os isochron age associated with these samples is extremely precise (< 1 m.y. uncertainty) at 253 Ma with an MSWD near unity. These data place a precise time pin in the studied section and the presumably correlative onshore exposures of the Ravnefjeld formation in East Greenland, indicating deposition of these shales immediately before the catastrophic changes at the Permo-Triassic boundary. Accompanying the isochron regression is a well-determined initial 187Os/188Os ratio of ca. 0.5, notably lower than seawater in the Lower Triassic (Xu et al. 2009). This Os isotopic composition for latest Permian seawater suggests an increase in mantle (or meteoric) material and/or a markedly reduced supply of eroded continental material heralding the up-coming extinction event. These Permian black shales are considered as alternative or complementary source rocks for some of the oil resources in the Norwegian Sea. Our work confirms geographically extensive Upper Permian black shale across the shelves of East Greenland and Norway, implying a major anoxia at the northern margin of Pangea shortly before the Permo-Triassic mass extinction. Xu et al. (2009) GCA, v. 73, no. 13. p. A1463

  5. Platinum Group Elements, 187OS/188OS and 87SR/86SR Isotope Systematics in Depleted Fluid-Modified Mariana Fore-Arc Peridotites

    NASA Astrophysics Data System (ADS)

    Harvey, J.; Savov, I. P.; Shirey, S. B.; Horan, M. F.; Mock, T. D.

    2012-12-01

    The serpentine mud volcanoes of the Izu-Bonin-Mariana (IBM) fore-arc, collected during Ocean Drilling Program Leg 195 [1], contain hard-rock clasts of serpentine sampled from close to the décollement, which separates the down-going Pacific slab from the overlying mantle wedge. These clasts preserve evidence for melt depletion (>25 % melt extraction in many instances) in a sub-arc environment, and extensive (40 - 100%) serpentinization due to subsequent fluid / peridotite interaction, e.g. [2]. Platinum-group element (PGE) abundances are not consistent with melt-depletion alone [3]. Fractionation between I-PGE (Os, Ir, Ru) has resulted in groups of IBM serpentinites with either a high chondrite-normalized Os/Ir ratio (OsN/IrN) or a low OsN/IrN ratio. Similarly, fractionation of P-PGE (Pt, Pd) is marked, and distinguishes the IBM serpentinites from worldwide abyssal peridotites. Interaction with high-pH fluids [4] may have partially oxidized mantle sulphide, the major primary host for PGE in these rocks, leading to partial breakdown to sulphate and the selective redistribution of certain PGE (Os, Ru, Pt), a feature normally associated with sub-aerial weathering [5], but which likely prevails in other oxidizing environments. In particular, the Re-Os systematics of the high (OsN/IrN) IBM serpentinites have been disturbed by the addition of Os. Unlike peridotite xenoliths associated with magmatic regions of subduction zones where subduction-related Os-addition is unequivocally radiogenic and derived from crustal material [6][7], where Os has been added to the IBM serpentinites it is unradiogenic and was most likely derived from within the oceanic mantle. IBM serpentinites therefore preserve osmium isotope ratios that are exclusively sub-chondritic (187Os/188Os ≤ 0.127), as previously reported [8]. These serpentinized peridotites were produced by at least a three-step process: melt depletion, serpentinization, and the mobilization of Os, Ru and Pt to produce low Os

  6. The Host Specificities of Baculovirus per os Infectivity Factors

    PubMed Central

    Song, Jingjiao; Wang, Xi; Hou, Dianhai; Huang, Huachao; Liu, Xijia; Deng, Fei; Wang, Hualin; Arif, Basil M.; Hu, Zhihong; Wang, Manli

    2016-01-01

    Baculoviruses are insect-specific pathogens with a generally narrow host ranges. Successful primary infection is initiated by the proper interaction of at least 8 conserved per os infectivity factors (PIFs) with the host’s midgut cells, a process that remains largely a mystery. In this study, we investigated the host specificities of the four core components of the PIF complex, P74, PIF1, PIF2 and PIF3 by using Helicoverpa armigera nucleopolyhedrovirus (HearNPV) backbone. The four pifs of HearNPV were replaced by their counterparts from a group I Autographa californica multiple nucleopolyhedrovirus (AcMNPV) or a group II Spodoptera litura nucleopolyhedrovirus (SpltNPV). Transfection and infection assays showed that all the recombinant viruses were able to produce infectious budded viruses (BVs) and were lethal to H. armigera larvae via intrahaemocoelic injection. However, feeding experiments using very high concentration of occlusion bodies demonstrated that all the recombinant viruses completely lost oral infectivity except SpltNPV pif3 substituted pif3-null HearNPV (vHaBacΔpif3-Sppif3-ph). Furthermore, bioassay result showed that the median lethal concentration (LC50) value of vHaBacΔpif3-Sppif3-ph was 23-fold higher than that of the control virus vHaBacΔpif3-Hapif3-ph, indicating that SpltNPV pif3 can only partially substitute the function of HearNPV pif3. These results suggested that most of PIFs tested have strict host specificities, which may account, at least in part, for the limited host ranges of baculoviruses. PMID:27454435

  7. Hexagonal OsB2 reduction upon heating in H2 containing environment

    DOE PAGES

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; ...

    2014-10-23

    The stability of hexagonal ReB2 type OsB2 powder upon heating under reforming gas was investigated. Pure Os metal particles were detected by powder X-ray diffraction starting at 375⁰ C and complete transformation of OsB2 to metallic Os was observed at 725⁰ C. The mechanisms of precipitation of metallic Os is proposed and changes in the lattice parameters of OsB2 upon heating are analysed in terms of the presence of oxygen or water vapour in the heating chamber. Previous studies suggested that Os atoms possess (0) valence, while B atoms possess both (+3) and ( 3) valences in the alternating boron/osmiummore » sheet structure of hexagonal (P63/mmc, No. 194) OsB2; if controllable method for Os removal from the lattice could be found, the opportunity would arise to form two-dimensional (2D) layers consisting of pure B atoms.« less

  8. Detection of undescribed ostreid herpesvirus 1 (OsHV-1) specimens from Pacific oyster, Crassostrea gigas.

    PubMed

    Martenot, Claire; Lethuillier, Ophélie; Fourour, Sarah; Oden, Elise; Trancart, Suzanne; Travaillé, Emmanuelle; Houssin, Maryline

    2015-11-01

    The ostreid herpesvirus 1 (OsHV-1) and variants were implicated in mass mortality affecting the young Pacific cupped oysters, Crassostrea gigas, in European countries and those around the world. From 2008 onwards, oyster mortality had greatly increased on the French coast and was associated with the detection of a new OsHV-1 variant, entitled OsHV-1 μVar. The OsHV-1 μVar is predominant in oysters; however, other OsHV-1 variants have been detected in samples collected during mortality periods or collected out of mortality periods in France, Ireland, Spain, Portugal, Italy, Mexico, United States, South Korea, Australia, and New Zealand. A retrospective study conducted on 1047 OsHV-1 specimens sampled mainly in France between 2009 and 2012, revealed 17 undescribed OsHV-1 variants found in 65 oyster samples. These specimens presented point mutations situated downstream and upstream from the microsatellite area in the C region (ORF 4/5) which were different from the OsHV-1 reference and the OsHV-1 μVar. In the present work, investigation was performed to further characterize these OsHV-1 specimens by sequencing two habitually targeted regions to study genetic polymorphism of the virus: ORF 41/42 and ORF 35-38. An OsHV-1 variant detected in six oyster samples, contained a nucleotide substitution in the C region which impacted the amino acid sequence and might modify the function of the unknown protein encoding by ORF 4. For the ORF 41/42 region, only two specimens presented a synonymous mutation in comparison with the OsHV-1 μVar. All specimens contained the same deletion with the OsHV-1 μVar in ORF 35-38. Then, a phylogenetic analysis based on the C region was performed to investigate the distribution of undescribed specimens among 21 OsHV-1 DNA sequences notified in GenBank and collected from different countries (France, Japan, New Zealand, China, Ireland, and United States) between 1995 and 2012. All analyzed samples and the OsHV-1 μVar were placed in the same

  9. Transcription Factor OsDOF18 Controls Ammonium Uptake by Inducing Ammonium Transporters in Rice Roots

    PubMed Central

    Wu, Yunfei; Yang, Wenzhu; Wei, Jinhuan; Yoon, Hyeryung; An, Gynheung

    2017-01-01

    Nitrogen is one of the most important mineral elements for plant growth. We studied the functional roles of Oryza sativa DNA BINDING WITH ONE FINGER 18 (OsDOF18) in controlling ammonium uptake. The growth of null mutants of OsDOF18 was retarded in a medium containing ammonium as the sole nitrogen source. In contrast, those mutants grew normally in a medium with nitrate as the sole nitrogen source. The gene expression was induced by ammonium but not by nitrate. Uptake of ammonium was lower in osdof18 mutants than in the wild type, while that of nitrate was not affected by the mutation. This indicated that OsDOF18 is involved in regulating ammonium transport. Among the 10 ammonium transporter genes examined here, expression of OsAMT1;1, OsAMT1;3, OsAMT2;1, and OsAMT4;1 was reduced in osdof18 mutants, demonstrating that the ammonium transporter genes function downstream of OsDOF18. Genes for nitrogen assimilation were also affected in the mutants. These results provide evidence that OsDOF18 mediates ammonium transport and nitrogen distribution, which then affects nitrogen use efficiency. PMID:28292004

  10. Os isotopic constraints on the identification of pyroxenite in the source of OIBs

    NASA Astrophysics Data System (ADS)

    Gibson, Sally; Dale, Chris; Geist, Dennis; Harpp, Karen

    2015-04-01

    The Re-Os isotope system has become increasingly used as a tracer of lithological heterogeneity in the convecting mantle, with radiogenic 187Os/188Os in high-Os oceanic basalts and picrites widely interpreted as evidence of a melt contribution from ancient recycled oceanic crust. When combined with 206Pb/204Pb and O isotopes, 187Os/188Os ratios have been used to identify distinct lithological units (i.e. sediments, gabbros and basalts). We report new 187Os/188Os for basalts with high Os (>40 ppt) and MgO from Galápagos, which range from near primitive mantle values (0.130) to highly radiogenic (0.155). While co-variations in 187Os/188Os and 206Pb/204Pb for some Galápagos basalts (Floreana-type) are HIMU like, and consistent with melting of ancient recycled oceanic crust, others have variable 187Os/188Os ratios and primitive to depleted mantle like 206Pb/204Pb. Similar variations in Os and Pb isotopic space have been interpreted in other OIB suites as melts from recycled ancient oceanic gabbros, entrained by upwelling mantle plumes. Nevertheless, a marked east-west spatial variation in 187Os/188Os of Galápagos basalts does not correlate with postulated lithological variations in the Galápagos plume based on trace element contents of olivine (Vidito et al., 2013). We show that basalts in eastern Galápagos with elevated 187Os/188Os and positive Sr anomalies occur in the vicinity of over-thickened 10 Ma gabbroic crust, that formed when the Galápagos plume was on-axis. We propose the elevated 187Os/188Os of Galápagos basalts are due to in-situ assimilation of young gabbroic lower crust, with high Re/Os, rather than melting of ancient recycled material in the Galápagos plume. In western Galápagos recent plume accreted crust is thick but more mafic, the melt flux higher and assimilation more sporadic. The contamination thresholds of Os and MgO in Galápagos basalts occur at higher contents than for many global OIBs (Azores, Iceland, Hawaii) and may reflect both a

  11. Re - Os isotopic constraints on the origin of volcanic rocks, Gorgona Island, Colombia: Os isotopic evidence for ancient heterogeneities in the mantle

    USGS Publications Warehouse

    Walker, R.J.; Echeverria, L.M.; Shirey, S.B.; Horan, M.F.

    1991-01-01

    The Re - Os isotopic systematics of komatiites and spatially associated basalts from Gorgona Island, Colombia, indicate that they were produced at 155??43 Ma. Subsequent episodes of volcanism produced basalts at 88.1??3.8 Ma and picritic and basaltic lavas at ca. 58 Ma. The age for the ultramafic rocks is important because it coincides with the late-Jurassic, early-Cretaceous disassembly of Pangea, when the North- and South-American plates began to pull apart. Deep-seated mantle upwelling possibly precipitated the break-up of these continental plates and caused a tear in the subducting slab west of Gorgona, providing a rare, late-Phanerozoic conduit for the komatiitic melts. Mantle sources for the komatiites were heterogeneous with respect to Os and Pb isotopic compositions, but had homogeneous Nd isotopic compositions (??Nd+9??1). Initial 187Os/186Os normalized to carbonaceous chondrites at 155 Ma (??Os) ranged from 0 to +22, and model-initial ?? values ranged from 8.17 to 8.39. The excess radiogenic Os, compared with an assumed bulk-mantle evolution similar to carbonaceous chondrites, was likely produced in portions of the mantle with long-term elevated Re concentrations. The Os, Pb and Nd isotopic compositions, together with major-element constraints, suggest that the sources of the komatiites were enriched more than 1 Ga ago by low (<20%) and variable amounts of a basalt or komatiite component. This component was added as either subducted oceanic crust or melt derived from greater depths in the mantle. These results suggest that the Re - Os isotope system may be a highly sensitive indicator of the presence of ancient subducted oceanic crust in mantle-source regions. ?? 1991 Springer-Verlag.

  12. Comparative study of structural, electronic and elastic behavior of OsAl and OsSi in B2 and B20 phases under pressure

    NASA Astrophysics Data System (ADS)

    Acharya, N.; Sanyal, S. P.

    2017-01-01

    The structural, electronic, bonding, elastic and mechanical properties of osmium intermetallic OsX (X = Al and Si) compounds in B2-phase as well as in B20-phase have been studied using full-potential linearized augmented plane wave method in the framework of density functional theory within generalized gradient approximation. The calculated lattice constants (a0) and bulk modulus (B) are in good agreement with experimental and available theoretical results. From the band structure calculations, it is shown that OsAl is metallic in both the phases while OsSi is found to be semiconductor in B20-phase with the indirect band gap of 0.33 eV but at high pressure the density of states at Fermi level N(EF) decreases and the bands spread over the entire reason in both the compounds. The elastic constants of these compounds obey the stability criteria for cubic system at 0 pressure as well as at high pressure. With increasing pressure, all the elastic constants for OsAl and OsSi increase almost linearly with pressure in both the phases except C44 for OsAl-B20 which shows its softening nature. Bonding nature is discussed in terms of charge density difference plots and Fermi surfaces.

  13. A transgenic study on affecting potato tuber yield by expressing the rice sucrose transporter genes OsSUT5Z and OsSUT2M.

    PubMed

    Sun, Aijun; Dai, Yan; Zhang, Xinsheng; Li, Chunmin; Meng, Kun; Xu, Honglin; Wei, Xiaoli; Xiao, Guifang; Ouwerkerk, Pieter B F; Wang, Mei; Zhu, Zhen

    2011-07-01

    In many plants, sucrose transporters are essential for both sucrose exports from sources and imports into sinks, indicating a function in assimilate partitioning. To investigate whether sucrose transporters can improve the yield of starch plant, potato plants (Solanum tuberosum L. cv. Désirée) were transformed with cDNAs of the rice sucrose transporter genes OsSUT5Z and OsSUT2M under the control of a tuber-specific, class-I patatin promoter. Compared to the controls, the average fructose content of OsSUT5Z transgenic tubers significantly increased. However, the content of the sugars and starch in the OsSUT2M transgenic potato tubers showed no obvious difference. Correspondingly, the average tuber yield, average number of tubers per plant and average weight of single tuber showed no significant difference in OsSUT2M transgenic tubers with controls. In the OsSUT5Z transgenic lines, the average tuber yield per plant was 1.9-fold higher than the controls, and the average number of tubers per plant increased by more than 10 tubers on average, whereas the average weight of a single tuber did not increase significantly. These results suggested that the average number of tubers per plant showed more contribution than the average weight of a single tuber to the tuber yield per plant.

  14. Re-Os Isotopes Distinguish Crust vs. Slab Inputs to Northern Cascade Arc Basalts

    NASA Astrophysics Data System (ADS)

    Mullen, E.; Gannoun, A.; Nauret, F.; Schiano, P.; Weis, D.

    2015-12-01

    Delineating the relative contributions of mantle, slab, and crust to arc magmas is particularly challenging in the Cascades where the continental crust is juvenile and contrasts little with magmas in traditional radiogenic isotope systems (Sr-Nd-Hf-Pb). The Re-Os isotope system offers a sensitive technique for evaluating these contributions because even young crust has significantly higher Os ratios than the mantle. We analyzed Re-Os isotope ratios in 33 primitive basalts from 9 volcanic centers of the northern Cascade Arc (Garibaldi Volcanic Belt, GVB). Although GVB basalts have mantle-like Sr-Pb-Nd-Hf ratios (Mullen & Weis, 2015, EPSL), the range in 187Os/188Os is very large (0.13-0.99) with [Os] of <1 to 17 ppt. Ten samples of subducting Cascadia Basin sediment and altered Juan de Fuca MORB are associated with high 187Os/188Os (0.68-0.92) and [Os] = 25-132 ppt. The GVB basalts define two groups: Group 1 (Cinder Cone/Mt. Garibaldi, Salal Glacier, Mt. Meager, Indian Pass/Glacier Peak) has low Os isotopic ratios (0.13-0.19), only slightly elevated relative to global mantle wedge peridotites (≤0.16), indicating minimal crustal contamination. Group 1 samples lie on Os-Sr isotope mixing curves indicating variable sediment input to the mantle. Os ratios of Group 2 basalts (Silverthrone, Bridge River, Elaho, Cheakamus, Mt. Baker, Glacier Peak) extend to extremely high values, up to 0.99, and lie on different Os-Sr mixing curves indicating addition of a crustal contaminant. Sr-Nd-Hf-Pb isotopic ratios cannot be used to identify this crustal input because Groups 1 and 2 are identical in these isotope systems. Interaction with a mafic underplate from older Cenozoic or accreted Mesozoic arcs is likely, and Re-Os analyses of basement samples (in progress) will provide a test of this hypothesis. This study reveals that most primitive magmas in the Cascades have suffered variable crustal contamination, but only the Re-Os isotope system has the potential to delineate the

  15. Molecular characterization and functional analysis of the OsPsbR gene family in rice.

    PubMed

    Li, Lihua; Ye, Taozhi; Gao, Xiaoling; Chen, Rongjun; Xu, Jinghong; Xie, Chen; Zhu, Jianqing; Deng, Xiaojian; Wang, Pingrong; Xu, Zhengjun

    2017-04-01

    Low temperature may exert a negative impact on agronomical productivity. PsbR was known as the 10 kDa Photosystem II polypeptide. Although plant PsbR is thought to play important roles in photosynthesis, little is known about the contribution of plant PsbR to abiotic stress resistance. The expression patterns of three OsPsbR gene family members, OsPsbR1, OsPsbR2, and OsPsbR3, were characterized in rice 'Nipponbare'. Under normal condition, OsPsbR1 and OsPsbR3 showed tissue-specific expression, while the expression of OsPsbR2 could not be detected in all tested tissues. OsPsbR1 was upregulated in response to cold stress, and downregulated under drought, salt, or heat conditions. The upregulation of OsPsbR3 was observed under the treatment of ABA, and its downregulation was detected under drought or heat conditions. Upregulation of OsPsbR1 in rice resulted in significantly increased resistance to cold, but did not affect the yield of rice. Furthermore, after 8 h cold-stress treatment, the expression levels of three cold stress-induced marker genes were significantly higher in the overexpression lines L11 and L19 in comparison with the wild type. All these results suggest that OsPsbR1 may play key roles in photosynthesis and cold stress response and thus has the potential to improve cold stress tolerance of crops.

  16. OsWRKY74, a WRKY transcription factor, modulates tolerance to phosphate starvation in rice

    PubMed Central

    Dai, Xiaoyan; Wang, Yuanyuan; Zhang, Wen-Hao

    2016-01-01

    The WRKY transcription factor family has 109 members in the rice genome, and has been reported to be involved in the regulation of biotic and abiotic stress in plants. Here, we demonstrated that a rice OsWRKY74 belonging to group III of the WRKY transcription factor family was involved in tolerance to phosphate (Pi) starvation. OsWRKY74 was localized in the nucleus and mainly expressed in roots and leaves. Overexpression of OsWRKY74 significantly enhanced tolerance to Pi starvation, whereas transgenic lines with down-regulation of OsWRKY74 were sensitive to Pi starvation. Root and shoot biomass, and phosphorus (P) concentration in rice OsWRKY74-overexpressing plants were ~16% higher than those of wild-type (WT) plants in Pi-deficient hydroponic solution. In soil pot experiments, >24% increases in tiller number, grain weight and P concentration were observed in rice OsWRKY74-overexpressing plants compared to WT plants when grown in P-deficient medium. Furthermore, Pi starvation-induced changes in root system architecture were more profound in OsWRKY74-overexpressing plants than in WT plants. Expression patterns of a number of Pi-responsive genes were altered in the OsWRKY74-overexpressing and RNA interference lines. In addition, OsWRKY74 may also be involved in the response to deficiencies in iron (Fe) and nitrogen (N) as well as cold stress in rice. In Pi-deficient conditions, OsWRKY74-overexpressing plants exhibited greater accumulation of Fe and up-regulation of the cold-responsive genes than WT plants. These findings highlight the role of OsWRKY74 in modulation of Pi homeostasis and potential crosstalk between P starvation and Fe starvation, and cold stress in rice. PMID:26663563

  17. [Crohn's disease associated with focal pulmonare lesion].

    PubMed

    Tagle, Martín; Barriga, José; Piñeiro, Andrés

    2003-01-01

    40 year-old male recently diagnosed with Crohn's disease. A routine chest X ray showed a round, well defined opacity in right lung field. A chest CT scan confirmed the finding and also described bronchiectasis. Patient had no respiratory symptoms. He was prescribed with oral sulfasalazine and corticosteroids with rapid improvement of intestinal symptoms as well as resolution of the pulmonary opacity. We describe the clinical presentation of a male newly diagnosed with Crohn's disease who was found to have an asymptomatic pulmonary lesion on imaging studies. Pulmonary complications have been previously described in inflamatory bowel disease being more common in ulcerative colitis than in Crohn's disease; these can involve the lung parenchyma, the tracheobronchial tree, and the pleura. The true prevalence and etiology of these lesions is currently unknown and are not necessarily associated with bowel disease activity. Abnormal pulmonary functions test have been reported during inflammatory bowel disease exacerbations, and although pulmonary findings can present with a variety of symptoms, subclinical presentations have also been described. Pulmonary manifestations are usually steoid-responsive, as was the case in our patients.

  18. Os layers spontaneously deposited on the Pt(111) electrode : XPS, STM and GIF-XAS study.

    SciTech Connect

    Rhee, C. K.; Wakisaka, M.; Tolmachev, Y.; Johnston, C.; Haasch, R.; Attenkofer, K.; Lu, G. Q.; You, H.; Wieckowski, A.; Univ. of Illinois Champaigh-Urbana

    2003-01-01

    Scanning tunneling microscopy (STM) characterized adlayers of spontaneously deposited osmium on a Pt(111) electrode were investigated using ex-situ X-ray photoemission spectroscopy (XPS) and in-situ grazing incidence fluorescence X-ray absorption spectroscopy (GIF-XAS). After a single spontaneous deposition, monoatomic (or nearly monoatomic) nanoislands of osmium are formed. The island diameter varies from 2 to 5 nm depending on the Os coverage, which in turn is adjusted by varying the concentration of the Os precursor salt (OsCl3) in the deposition bath and/or by the deposition time. XPS reveals three oxidation states: a metallic Os (the 4f7/2 core level binding energy of 50.8 eV), Os(IV) (51.5 eV) and Os(VIII) (52.4 eV). The metallic osmium exists at potentials below 500 mV (vs. RHE) while above 500 mV osmium is oxidized to Os(IV). Electrodissolution of osmium begins above 900 mV and occurs simultaneously with platinum oxidation. At ca. 1200 mV V versus the RHE reference, the oxidation state of some small amounts of osmium that survive dissolution is the Os(VIII). We demonstrate, for the first time, that mixed or odd valencies of osmium exist on the platinum surface at potentials higher that 800 mV. In-situ GIF-XAS measurements of an Os LIII edge also reveal the presence of three Os oxidation states. Namely, below the electrode potential of 400 mV, the X-ray fluorescent energy at maximum absorption is 10.8765 keV, and is characteristic of the metallic Os. In the potential range between 500 and 1000 mV this energy is gradually shifted to higher values, assignable to higher valencies of osmium, like Os(IV). This tendency continues to higher potentials consistent with the third, highly oxidized osmium form present, most likely Os(VIII). The variation of the 'raw edge jump height' of Os with the electrode potential, which is equivalent to a drop in osmium surface concentration, demonstrates that the electrochemical stripping of Os begins below 1.0 V versus RHE, as

  19. 187Re - 187Os Nuclear Geochronometry: A New Dating Method Applied to Old Ores

    NASA Astrophysics Data System (ADS)

    Roller, Goetz

    2015-04-01

    187Re - 187Os nuclear geochronometry is a newly developed dating method especially (but not only) for PGE hosting magmatic ore deposits. It combines ideas of nuclear astrophysics with geochronology. For this, the concept of sudden nucleosynthesis [1-3] is used to calculate so-called nucleogeochronometric Rhenium-Osmium two-point-isochrone (TPI) ages. Here, the method is applied to the Sudbury Igneous Complex (SIC) and the Stillwater Complex (SC), using a set of two nuclear geochronometers. They are named the BARBERTON ( Re/Os = 0.849, 187Os/186Os = 10.04 ± 0.015 [4]) and the IVREA (Re/Os = 0.951, 187Os/186Os = 1.9360 ± 0.0015 [5]) nuclear geochronometer. Calculated TPI ages are consistent with results from Sm-Nd geochronology, a previously published Re-Os Molybdenum age of 2740 ± 80 Ma for the G-chromitite of the SC [6] and a Re-Os isochrone age of 1689 ± 160 Ma for the Strathcona ores of the SIC [7]. This leads to an alternative explanation of the peculiar and enigmatic 187Os/186Osi isotopic signatures reported from both ore deposits. For example, for a TPI age of 2717 ± 100 Ma the Ultramafic Series of the SC contains both extremely low (subchrondritic) 187Os/186Osi ratios (187Os/186Osi = 0.125 ± 0.067) and extremely radiogenic isotopic signatures (187Os/186Osi = 6.55 ± 1.7, [6]) in mineral separates (chromites) and whole rock samples, respectively. Within the Strathcona ores of the SIC, even more pronounced radiogenic 187Os/186Os initial ratios can be calculated for TPI ages between 1586 ± 63 Ma (187Os/186Osi = 8.998 ± 0.045) and 1733 ± 84 Ma (187Os/186Osi = 8.901 ± 0.059). These results are in line with the recalculated Re-Os isochrone age of 1689 ± 160 Ma (187Os/186Osi = 8.8 ± 2.3 [7]). In the light of nuclear geochronometry, the occurrence of such peculiar isotopic 187Os/186Osi signatures within one and the same lithological horizon are plausible if explained by mingling of the two nucleogeochronometric (BARBERTON and IVREA) reservoirs containing

  20. Molecular analysis of OsLEA4 and its contributions to improve E. coli viability.

    PubMed

    Hu, Tingzhang; Zeng, Hua; He, Shuai; Wu, Yingmei; Wang, Guixue; Huang, Xiaoyun

    2012-01-01

    OsLEA4, a late embryogenesis abundant (LEA) protein gene from rice (Oryza sativa L.), contains a 312-bp open reading frame encoding a putative polypeptide of 103 amino acids with a calculated molecular mass of 11.19 kDa and a theoretical pI of 10.04. OsLEA4 polypeptide is rich in Ala (22%), Lys (15%), Glu (9%), His (8%), Thr (8%), and Arg (7%) and lacking in Trp, Cys, Asn, and Phe residues. OsLEA4 protein contains a Pfam:LEA_1 domain architecture at positions 1-73 with three α-helical domains and without β-sheet domain. In silico predictions showed that OsLEA4 protein was strongly hydrophilic with the grand average of hydropathy value of -0.816 and instability index of 27.31. The hydrophilic regions were found in the conserved motif of OsLEA4. OsLEA4 gene was introduced into Escherichia coli, and a fusion protein (∼29.4 kDa) was expressed after isopropylthio-β-D: -galactoside inducting by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. OsLEA4 protein enhanced the tolerance of E. coli recombinant to high salinity, heat, freezing, and UV radiation, which suggested that OsLEA4 protein may play a protective role under stressed conditions. This is the first successful use of E. coli as a prokaryotic system for LEA production from rice.

  1. Ferrimagnetism in the double perovskite Ca2FeOsO6: A density functional study

    NASA Astrophysics Data System (ADS)

    Wang, Hongbo; Zhu, Shasha; Ou, Xuedong; Wu, Hua

    2014-08-01

    Using density functional calculations, we find that the newly synthesized Ca2FeOsO6 has the high-spin Fe3+ (3d5)-Os5+ (5d3) state. The octahedral Os5+ ion has a large intrinsic exchange splitting, and its t2g↑3 configuration makes the spin-orbit coupling ineffective. Moreover, there is a strong antiferromagnetic (AF) coupling between the neighboring Fe3+ (S=5/2) and Os5+ (S=-3/2), but the AF couplings within both the fcc Fe3+ and Os5+ sublattices are one order of magnitude weaker. Therefore a magnetic frustration is suppressed and a stable ferrimagnetic ground state appears. This ferrimagnetic order is due to the virtual hopping of the t2g electrons from Os5+ (t2g↓3) to Fe3+ (t2g↑3eg↑2). However, if the experimental bended Fe3+-O2--Os5+ exchange path gets straight, the eg hopping from Fe3+ (t2g↑3eg↑2) to Os5+ (t2g↑3) would be facilitated and then a ferromagnetic (FM) coupling would occur.

  2. Iron deficiency regulated OsOPT7 is essential for iron homeostasis in rice.

    PubMed

    Bashir, Khurram; Ishimaru, Yasuhiro; Itai, Reiko Nakanishi; Senoura, Takeshi; Takahashi, Michiko; An, Gynheung; Oikawa, Takaya; Ueda, Minoru; Sato, Aiko; Uozumi, Nobuyuki; Nakanishi, Hiromi; Nishizawa, Naoko K

    2015-05-01

    The molecular mechanism of iron (Fe) uptake and transport in plants are well-characterized; however, many components of Fe homeostasis remain unclear. We cloned iron-deficiency-regulated oligopeptide transporter 7 (OsOPT7) from rice. OsOPT7 localized to the plasma membrane and did not transport Fe(III)-DMA or Fe(II)-NA and GSH in Xenopus laevis oocytes. Furthermore OsOPT7 did not complement the growth of yeast fet3fet4 mutant. OsOPT7 was specifically upregulated in response to Fe-deficiency. Promoter GUS analysis revealed that OsOPT7 expresses in root tips, root vascular tissue and shoots as well as during seed development. Microarray analysis of OsOPT7 knockout 1 (opt7-1) revealed the upregulation of Fe-deficiency-responsive genes in plants grown under Fe-sufficient conditions, despite the high Fe and ferritin concentrations in shoot tissue indicating that Fe may not be available for physiological functions. Plants overexpressing OsOPT7 do not exhibit any phenotype and do not accumulate more Fe compared to wild type plants. These results indicate that OsOPT7 may be involved in Fe transport in rice.

  3. Discrimination against Latina/os: A Meta-Analysis of Individual-Level Resources and Outcomes

    ERIC Educational Resources Information Center

    Lee, Debbiesiu L.; Ahn, Soyeon

    2012-01-01

    This meta-analysis synthesizes the findings of 60 independent samples from 51 studies examining racial/ethnic discrimination against Latina/os in the United States. The purpose was to identify individual-level resources and outcomes that most strongly relate to discrimination. Discrimination against Latina/os significantly results in outcomes…

  4. Semantic Overlays in Educational Content Networks--The hylOs Approach

    ERIC Educational Resources Information Center

    Engelhardt, Michael; Hildebrand, Arne; Lange, Dagmar; Schmidt, Thomas C.

    2006-01-01

    Purpose: The paper aims to introduce an educational content management system, Hypermedia Learning Objects System (hylOs), which is fully compliant to the IEEE LOM eLearning object metadata standard. Enabled through an advanced authoring toolset, hylOs allows the definition of instructional overlays of a given eLearning object mesh.…

  5. A new synthesis route for Os-complex modified redox polymers for potential biofuel cell applications.

    PubMed

    Pöller, Sascha; Beyl, Yvonne; Vivekananthan, Jeevanthi; Guschin, Dmitrii A; Schuhmann, Wolfgang

    2012-10-01

    A new synthesis route for Os-complex modified redox polymers was developed. Instead of ligand exchange reactions for coordinative binding of suitable precursor Os-complexes at the polymer, Os-complexes already exhibiting the final ligand shell containing a suitable functional group were bound to the polymer via an epoxide opening reaction. By separation of the polymer synthesis from the ligand exchange reaction at the Os-complex, the modification of the same polymer backbone with different Os-complexes or the binding of the same Os-complex to a number of different polymer backbones becomes feasible. In addition, the Os-complex can be purified and characterized prior to its binding to the polymer. In order to further understand and optimize suitable enzyme/redox polymer systems concerning their potential application in biosensors or biofuel cells, a series of redox polymers was synthesized and used as immobilization matrix for Trametes hirsuta laccase. The properties of the obtained biofuel cell cathodes were compared with similar biocatalytic interfaces derived from redox polymers obtained via ligand exchange reaction of the parent Os-complex with a ligand integrated into the polymer backbone during the polymer synthesis.

  6. OsTCP19 influences developmental and abiotic stress signaling by modulating ABI4-mediated pathways

    PubMed Central

    Mukhopadhyay, Pradipto; Tyagi, Akhilesh Kumar; Tyagi, Akhilesh Kumar

    2015-01-01

    Class-I TCP transcription factors are plant-specific developmental regulators. In this study, the role of one such rice gene, OsTCP19, in water-deficit and salt stress response was explored. Besides a general upregulation by abiotic stresses, this transcript was more abundant in tolerant than sensitive rice genotypes during early hours of stress. Stress, tissue and genotype-dependent retention of a small in-frame intron in this transcript was also observed. Overexpression of OsTCP19 in Arabidopsis caused upregulation of IAA3, ABI3 and ABI4 and downregulation of LOX2, and led to developmental abnormalities like fewer lateral root formation. Moreover, decrease in water loss and reactive oxygen species, and hyperaccumulation of lipid droplets in the transgenics contributed to better stress tolerance both during seedling establishment and in mature plants. OsTCP19 was also shown to directly regulate a rice triacylglycerol biosynthesis gene in transient assays. Genes similar to those up- or downregulated in the transgenics were accordingly found to coexpress positively and negatively with OsTCP19 in Rice Oligonucleotide Array Database. Interactions of OsTCP19 with OsABI4 and OsULT1 further suggest its function in modulation of abscisic acid pathways and chromatin structure. Thus, OsTCP19 appears to be an important node in cell signaling which crosslinks stress and developmental pathways. PMID:25925167

  7. Comparative 187Re-187Os systematics of chondrites: Implications regarding early solar system processes

    USGS Publications Warehouse

    Walker, R.J.; Horan, M.F.; Morgan, J.W.; Becker, H.; Grossman, J.N.; Rubin, A.E.

    2002-01-01

    A suite of 47 carbonaceous, enstatite, and ordinary chondrites are examined for Re-Os isotopic systematics. There are significant differences in the 187Re/188Os and 187Os/188Os ratios of carbonaceous chondrites compared with ordinary and enstatite chondrites. The average 187Re/188Os for carbonaceous chondrites is 0.392 ?? 0.015 (excluding the CK chondrite, Karoonda), compared with 0.422 ?? 0.025 and 0.421 ?? 0.013 for ordinary and enstatite chondrites (1?? standard deviations). These ratios, recast into elemental Re/Os ratios, are as follows: 0.0814 ?? 0.0031, 0.0876 ?? 0.0052 and 0.0874 ?? 0.0027 respectively. Correspondingly, the 187Os/188Os ratios of carbonaceous chondrites average 0.1262 ?? 0.0006 (excluding Karoonda), and ordinary and enstatite chondrites average 0.1283 ?? 0.0017 and 0.1281 ?? 0.0004, respectively (1?? standard deviations). The new results indicate that the Re/Os ratios of meteorites within each group are, in general, quite uniform. The minimal overlap between the isotopic compositions of ordinary and enstatite chondrites vs. carbonaceous chondrites indicates long-term differences in Re/Os for these materials, most likely reflecting chemical fractionation early in solar system history. A majority of the chondrites do not plot within analytical uncertainties of a 4.56-Ga reference isochron. Most of the deviations from the isochron are consistent with minor, relatively recent redistribution of Re and/or Os on a scale of millimeters to centimeters. Some instances of the redistribution may be attributed to terrestrial weathering; others are most likely the result of aqueous alteration or shock events on the parent body within the past 2 Ga. The 187Os/188Os ratio of Earth's primitive upper mantle has been estimated to be 0.1296 ?? 8. If this composition was set via addition of a late veneer of planetesimals after core formation, the composition suggests the veneer was dominated by materials that had Re/Os ratios most similar to ordinary and

  8. γ -ray spectroscopy of low-lying excited states and shape competition in 194Os

    NASA Astrophysics Data System (ADS)

    Daniel, T.; Kisyov, S.; Regan, P. H.; Marginean, N.; Podolyák, Zs.; Marginean, R.; Nomura, K.; Rudigier, M.; Mihai, R.; Werner, V.; Carroll, R. J.; Gurgi, L. A.; Oprea, A.; Berry, T.; Serban, A.; Nita, C. R.; Sotty, C.; Suvaila, R.; Turturica, A.; Costache, C.; Stan, L.; Olacel, A.; Boromiza, M.; Toma, S.

    2017-02-01

    The properties of excited states in the neutron-rich nucleus 194Os have been investigated using the 192Os(18O,16O )194Os reaction with an 80 MeV beam provided by the IFIN-HH Laboratory, Bucharest. Discrete γ -ray decays from excited states have been measured using the hybrid HPGe-LaBr3(Ce ) array RoSPHERE. The current work identifies a number of previously unreported low-lying nonyrast states in 194Os as well as the first measurement of the half-life of the yrast 2+ state of 302(50) ps. This is equivalent to a B (E 2 :2+→0+) =45 (16 ) W.u. and intrinsic quadrupole deformation of βeff=0.14 (1 ) . The experimental results are compared with Hartree-Fock-Bogoliubov-interacting-boson-model calculations and are consistent with a reduction in a quadrupole collectivity in Os isotopes with increasing neutron number.

  9. Re-Os Systematics and HSE Distribution in Metal from Ochansk (H4) Chondrite

    NASA Technical Reports Server (NTRS)

    Smoliar, M. I.; Horan, M. F.; Alexander, C. M. OD.; Walker, R. J.

    2003-01-01

    Previous studies of the Re-Os systematics of chondrites have documented considerable variation in the Re/Os ratios of whole rock samples. For some whole rock chondrites, Re-Os systematics display large deviations from the primitive isochron that are considerably larger than deviations in other isotope systems. Possible interpretation of these facts is that the Re-Os system in chondrites is particularly sensitive to post-formation alteration processes, thus providing a useful tool to examine such processes. Significant variations that have been detected in highly siderophile element (HSE) patterns for ordinary chondrites support this conclusion. We report Re-Os isotope data for metal separates from the Ochansk H4 chondrite coupled with abundance data for Ru, Pd, Ir, and Pt, determined in the same samples by isotope dilution. We chose this meteorite mainly because it is an observed fall with minimal signs of weathering, and its low metamorphic grade (H4) and shock stage (S3).

  10. Tracking Melt-Rock Reaction Using Os Isotopes: Maqsad Diapir (Oman Ophiolite)

    NASA Astrophysics Data System (ADS)

    Godard, M.; Alard, O.; Lorand, J.; Burton, K. W.

    2001-12-01

    The exceptional exposure of the Oman ophiolite allows to study in detail the mantle processes occurring beneath a spreading centre. We have carried out a Re-Os pilot study focussed on the Maqsad diapir in the western part of the Sumail massif. The Maqsad diapir is roughly constituted of 3 petrographic units: 1, the main harzburgitic domain (MHD); 2, the diapir harzburgite (DH) showing plunging lineation; 3, a thick dunitic, mantle-crust transition zone (MTZ) topping the DH section. The MHD samples are characterised by Os content about 4 ppb and 187Os/188Os down to 0.1210. These features are in agreement with a >15% melt extraction. These unradiogenic Os compositions yield a model Re-depletion age ca. 1 Ga, similar to other Re-Os model age obtained for other oceanic related mantle samples worldwide. Samples from the DH domain despite similar range in Al2O3 content show more radiogenic Os composition (0.1240<187Os/188Os <0.1298). The MTZ dunites show even more radiogenic Os composition (0.1352<187Os/188Os <0.1399). The MTZ dunite are further characterised by low Os content (<1.5 ppb) not in agreement with the well know high compatible nature of Os. These observations are inconsistent with a residual origin after melting for these dunites. In contrast, Os systematic indicate than the MTZ dunites as well as the diapir harzburgites are not a mere product of melt depletion but rather result from extensive melt-rock reaction as previously demonstrated (e.g., Kelemen et al., 1995; Godard et al., 2000). Those authors have postulated that dunites are the product of melt-rock reaction leading to the crystallisation of olivine and Fe-enrichment (leading to low Mg-number) similar but less extensive process has been envisaged for the diapir harzburgite. 187Os/188Os is inversely correlated with the Mg-number of the MTZ and DH samples. Suggesting that indeed the petrographic and geochemical characteristics of both domains are due to the same process occurring at various extend

  11. Picomolar inhibition of cholera toxin by a pentavalent ganglioside GM1os-calix[5]arene.

    PubMed

    Garcia-Hartjes, Jaime; Bernardi, Silvia; Weijers, Carel A G M; Wennekes, Tom; Gilbert, Michel; Sansone, Francesco; Casnati, Alessandro; Zuilhof, Han

    2013-07-14

    Cholera toxin (CT), the causative agent of cholera, displays a pentavalent binding domain that targets the oligosaccharide of ganglioside GM1 (GM1os) on the periphery of human abdominal epithelial cells. Here, we report the first GM1os-based CT inhibitor that matches the valency of the CT binding domain (CTB). This pentavalent inhibitor contains five GM1os moieties linked to a calix[5]arene scaffold. When evaluated by an inhibition assay, it achieved a picomolar inhibition potency (IC50 = 450 pM) for CTB. This represents a significant multivalency effect, with a relative inhibitory potency of 100,000 compared to a monovalent GM1os derivative, making GM1os-calix[5]arene one of the most potent known CTB inhibitors.

  12. Paleoproterozoic pyrobitumen: Re-Os goechemistry reveals the fate of giant carbon accumulations in Russian Karelia

    NASA Astrophysics Data System (ADS)

    Hannah, J. L.; Stein, H. J.; Yang, G.; Zimmerman, A.

    2010-12-01

    Carbon-rich pyrobitumen is exposed in abundance in the Onega Basin of Karelia, northwestern Russia - the fossil remains of a giant oil field [1]. The pyrobitumen, locally termed “shungite”, occurs as veins, lenses, and droplets within the Zaonezhskaya and Kondopozhskaya Formations, part of a Paleoproterozoic platform sequence developed on a rifted continental margin. In its purest form, this material approaches 100% C. Less pure pyrobitumen occurs in Corg-rich siltstones, which are intercalated with basaltic flows and sills, including peperites. Locally, the pyrobitumen forms a massive organo-siliceous diapir, cross-cutting the sedimentary section. A Re-Os isochron for six samples of Corg-rich siltstone taken from a mine adit in Shunga village yields a precise age of 2.05 Ga [2], fitting existing constraints for the depositional age. The initial 187Os/188Os ratio given by the isochron for the Shunga adit samples is within uncertainty of chondritic (0.113 at 2.05 Ga), as expected in a restricted rift basin dominated by hydrothermal Os. Re-Os data for samples from ICDP FAR-DEEP drillhole 13A near Shunga village, tell the rest of the story. Eleven ~500 mg samples, drilled from two 3-cm intervals 0.5 m apart in a single core, yield an isochron age of ~1.73 Ga with initial 187Os/188Os = 5. This age is consistent with the latest phase of the Svecofennian orogeny [3], known to have impacted the Onega Basin. Assuming isotopic homogenization (maturation) of the pyrobitumen took place during a relatively brief thermal maximum, the largest control on the present-day 187Os/188Os is the 187Re/188Os. The 187Re/188Os for the 17 siltstone samples analyzed to date range from 280 to 1250. An average 187Re/188Os of 900 will raise the 187Os/188Os from 0.113 to about 5 during the 320 m.y. between deposition (2.05 Ga) and maturation (1.73 Ga) - precisely the value determined by our isochron. Similarly, the lower 187Re/188Os of 280 for three samples of lustrous pyrobitumen from the

  13. RLIM interacts with Smurf2 and promotes TGF-{beta} induced U2OS cell migration

    SciTech Connect

    Huang, Yongsheng; Yang, Yang; Gao, Rui; Yang, Xianmei; Yan, Xiaohua; Wang, Chenji; Jiang, Sirui; Yu, Long

    2011-10-14

    Highlights: {yields} RLIM directly binds to Smurf2. {yields} RLIM enhances TGF-{beta} responsiveness in U2OS cells. {yields} RLIM promotes TGF-{beta} driven migration of osteosarcoma U2OS cells. -- Abstract: TGF-{beta} (transforming growth factor-{beta}), a pleiotropic cytokine that regulates diverse cellular processes, has been suggested to play critical roles in cell proliferation, migration, and carcinogenesis. Here we found a novel E3 ubiquitin ligase RLIM which can directly bind to Smurf2, enhancing TGF-{beta} responsiveness in osteosarcoma U2OS cells. We constructed a U2OS cell line stably over-expressing RLIM and demonstrated that RLIM promoted TGF-{beta}-driven migration of U2OS cells as tested by wound healing assay. Our results indicated that RLIM is an important positive regulator in TGF-{beta} signaling pathway and cell migration.

  14. Oxygen interaction with hexagonal OsB2 at high temperature

    DOE PAGES

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; ...

    2016-08-10

    The stability of ReB2-type hexagonal OsB2 powder at high temperature with oxygen presence has been studied by thermogravimetric analysis, differential scanning calorimetry, SEM, EDS, and high-temperature scanning transmission electron microscopy and XRD. Results of the study revealed that OsB2 ceramics interact readily with oxygen present in reducing atmosphere, especially at high temperature and produces boric acid, which decomposes on the surface of the powder resulting in the formation of boron vacancies in the hexagonal OsB2 lattice as well as changes in the stoichiometry of the compound. It was also found that under low oxygen partial pressure, sintering of OsB2 powdersmore » occurred at a relatively low temperature (900°C). Finally, hexagonal OsB2 ceramic is prone to oxidation and it is very sensitive to oxygen partial pressures, especially at high temperatures.« less

  15. A novel gene OsAHL1 improves both drought avoidance and drought tolerance in rice

    PubMed Central

    Zhou, Liguo; Liu, Zaochang; Liu, Yunhua; Kong, Deyan; Li, Tianfei; Yu, Shunwu; Mei, Hanwei; Xu, Xiaoyan; Liu, Hongyan; Chen, Liang; Luo, Lijun

    2016-01-01

    A novel gene, OsAHL1, containing an AT-hook motif and a PPC domain was identified through genome-wide profiling and analysis of mRNAs by comparing the microarray of drought-challenged versus normally watered rice. The results indicated OsAHL1 has both drought avoidance and drought tolerance that could greatly improve drought resistance of the rice plant. Overexpression of OsAHL1 enhanced multiple stress tolerances in rice plants during both seedling and panicle development stages. Functional studies revealed that OsAHL1 regulates root development under drought condition to enhance drought avoidance, participates in oxidative stress response and also regulates the content of chlorophyll in rice leaves. OsAHL1 specifically binds to the A/T rich sequence region of promoters or introns, and hence directly regulates the expression of many stress related downstream genes. PMID:27453463

  16. Cutin monomer induces expression of the rice OsLTP5 lipid transfer protein gene.

    PubMed

    Kim, Tae Hyun; Park, Jong Ho; Kim, Moon Chul; Cho, Sung Ho

    2008-01-01

    Treatment with the cutin monomer 16-hydroxypalmitic acid (HPA), a major component of cutin, elicited the synthesis of hydrogen peroxide (H2O2) in rice leaves and induced the expression of the lipid transfer protein gene OsLTP5. Treatment with HPA also induced expression of OsLTP1, OsLTP2, and the pathogen-related PR-10 genes to a lesser extent. The OsLTP5 transcript was expressed prominently in stems and flowers, but was barely detectable in leaves. Expression of OsLTP5 was induced in shoots in response to ABA and salicylic acid. It is proposed that HPA is perceived by rice as a signal, inducing defense reactions.

  17. Characterization of metal removal by os sepiae of Sepiella maindroni Rochebrune from aqueous solutions.

    PubMed

    Li, You-Zhi; Pan, Hong; Xu, Jian; Fan, Xian-Wei; Song, Xian-Chong; Zhang, Qian; Xu, Jin; Liu, Yang

    2010-07-15

    To develop low cost metal adsorbents with less secondary pollution, metal adsorption from the aqueous solutions by the raw os sepiae (ROS) and alkali (NaOH)-pretreated OS (APOS) of the cuttlefish (Sepiella maindroni Rochebrune) was characterized. The capacities of adsorption of ROS and APOS were estimated to be 299.26 mg Cu g(-1) and 299.58 mg Cu g(-1), respectively. Metal adsorption by OS was significantly improved by appropriately increasing initial pH in the solution but hardly affected by temperature change within a wide range of 15-45 degrees C. Cu adsorption of both ROS and APOS was well described neither by Langmuir model nor by Freundlich model. Metal adsorption by OS fell in the order of Fe > Cu approximately = Cd > Zn in the solution with mixed metals, but followed the sequence of Cd > Cu > Fe approximately = Zn in the solutions respectively, with a single metal of Fe, Cu, Cd and Zn. The changes in Ca amounts in OS and solutions in adsorption strongly correlated with removal efficiencies of the metals. Obvious shifts of stretching bands of numbers of groups in OS after and before adsorption and the pretreatment occurred. It was concluded: (1) that metal adsorption by OS involves ion exchange, which occurred mainly between Ca rather than K and Na that OS itself contains and metals that were added in the solution, (2) that metal adsorption-promoting effects by NaOH pretreatment likely involve deprotonation of surface groups in OS, exposure of more functional groups, and increase in specific surface areas and (3) that related mechanisms for adsorption also likely include surface complexation, electrostatic adsorption and even micro-deposition. The results also indicated that OS is a very promising absorbent for metal removal from electroplating wastewater.

  18. Preparation and certification of Re-Os dating reference materials: Molybdenites HLP and JDC

    USGS Publications Warehouse

    Du, A.; Wu, S.; Sun, D.; Wang, Shaoming; Qu, W.; Markey, R.; Stain, H.; Morgan, J.; Malinovskiy, D.

    2004-01-01

    Two Re-Os dating reference material molybdenites were prepared. Molybdenite JDC and molybdenite HLP are from a carbonate vein-type molybdenum-(lead)- uranium deposit in the Jinduicheng-Huanglongpu area of Shaanxi province, China. The samples proved to be homogeneous, based on the coefficient of variation of analytical results and an analysis of variance test. The sampling weight was 0.1 g for JDC and 0.025 g for HLP. An isotope dilution method was used for the determination of Re and Os. Sample decomposition and preconcentration of Re and Os prior to measurement were accomplished using a variety of methods: acid digestion, alkali fusion, ion exchange and solvent extraction. Negative thermal ionisation mass spectrometry and inductively coupled plasma-mass spectrometry were used for the determination of Re and 187Os concentration and isotope ratios. The certified values include the contents of Re and Os and the model ages. For HLP, the Re content was 283.8 ?? 6.2 ??g g-1, 187Os was 659 ?? 14 ng g-1 and the Re-Os model age was 221.4 ?? 5.6 Ma. For JDC, the Re content was 17.39 ?? 0.32 ng g-1, 187Os was 25.46 ?? 0.60 ng g-1 and the Re-Os model age was 139.6 ?? 3.8 Ma. Uncertainties for both certified reference materials are stated at the 95% level of confidence. Three laboratories (from three countries: P.R. China, USA, Sweden) joined in the certification programme. These certified reference materials are primarily useful for Re-Os dating of molybdenite, sulfides, black shale, etc.

  19. Re-Os Geochronology Pins Age and Os Isotope Composition of Middle Triassic Black Shales and Seawater, Barents Sea and Spitsbergen (Svalbard)

    NASA Astrophysics Data System (ADS)

    Xu, G.; Hannah, J. L.; Bingen, B.; Stein, H. J.; Yang, G.; Zimmerman, A.; Weitschat, W.; Weiss, H. M.

    2008-12-01

    Absolute age control throughout the Triassic is extraordinarily sparse. Two "golden spikes" have been added recently (http://www.stratigraphy.org/cheu.pdf) within the otherwise unconstrained Triassic, but ages of stage boundaries remain controversial. Here we report two Re-Os isochrons for Anisian (Middle Triassic) black shales from outcrop in western Svalbard and drill core from the Svalis Dome about 600 km to the SE in the Barents Sea. Black shales of the Blanknuten Member, Botneheia Formation, from the type section at Botneheia, western Spitsbergen (Svalbard), have total organic carbon (TOC) contents of 2.6 to 6.0 wt%. Rock-Eval data suggest moderately mature (Tmax = 440-450° C) Type II-III kerogens (Hydrogen Index (HI) = 232-311 mg HC/g TOC). Re-Os data yield a well-constrained Model 3 age of 241 Ma and initial 187Os/188Os (Osi) of 0.83 (MSWD = 16, n = 6). Samples of the possibly correlative Steinkobbe Formation from IKU core hole 7323/07-U-04 into the Svalis Dome in the Barents Sea (at about 73°30'N, 23°15'E) have TOC contents of 1.4 to 2.4%. Rock-Eval data suggest immature (Tmax = 410-430°) Type II-III kerogens (HI = 246-294 mg HC/g TOC). Re-Os data yield a precise Model 1 age of 239 Ma and Osi of 0.776 (MSWD = 0.2, n = 5). The sampled section of Blanknuten shale underlies a distinctive Frechitas (formerly Ptychites) layer, and is therefore assumed to be middle Anisian. The Steinkobbe core was sampled at 99-100 m, just above the Olenekian-Anisian transition. It is therefore assumed to be lower Anisian. The two isochron ages overlap within uncertainty, and fall within constraints provided by biozones and the current ICS-approved stage boundary ages. The Re-Os ages support the correlation of the Botneheia and Steinkobbe formations. The nearly identical Osi ratios suggest regional homogeneity of seawater and provide new information for the Os seawater curve, marking a relatively high 187Os/188Os ratio during profound ocean anoxia in the Middle Triassic.

  20. Neutron physics of the Re/Os clock. III. Resonance analyses and stellar (n,gamma) cross sections of {sup 186,187,188}Os

    SciTech Connect

    Fujii, K.; Abbondanno, U.; Belloni, F.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Kaeppeler, F.; Audouin, L.; Dillmann, I.; Heil, M.; Plag, R.; Voss, F.; Walter, S.; Wisshak, K.; Mengoni, A.; Domingo-Pardo, C.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2010-07-15

    Neutron resonance analyses have been performed for the capture cross sections of {sup 186}Os, {sup 187}Os, and {sup 188}Os measured at the n{sub T}OF facility at cern. Resonance parameters have been extracted up to 5, 3, and 8 keV, respectively, using the sammy code for a full R-matrix fit of the capture yields. From these results average resonance parameters were derived by a statistical analysis to provide a comprehensive experimental basis for modeling of the stellar neutron capture rates of these isotopes in terms of the Hauser-Feshbach statistical model. Consistent calculations for the capture and inelastic reaction channels are crucial for the evaluation of stellar enhancement factors to correct the Maxwellian averaged cross sections obtained from experimental data for the effect of thermally populated excited states. These factors have been calculated for the full temperature range of current scenarios of s-process nucleosynthesis using the combined information of the experimental data in the region of resolved resonances and in the continuum. The consequences of this analysis for the s-process component of the {sup 187}Os abundance and the related impact on the evaluation of the time duration of galactic nucleosynthesis via the Re/Os cosmochronometer are discussed.

  1. Neutron physics of the Re/Os clock. III. Resonance analyses and stellar (n,γ) cross sections of Os186,187,188

    NASA Astrophysics Data System (ADS)

    Fujii, K.; Mosconi, M.; Mengoni, A.; Domingo-Pardo, C.; Käppeler, F.; Abbondanno, U.; Aerts, G.; Álvarez-Pol, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Bisterzo, S.; Calviani, M.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Furman, W.; Gallino, R.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Karamanis, D.; Karadimos, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Massimi, C.; Mastinu, P.; Milazzo, P. M.; Moreau, C.; Neves, F.; Oberhummer, H.; Oshima, M.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2010-07-01

    Neutron resonance analyses have been performed for the capture cross sections of Os186, Os187, and Os188 measured at the n_TOF facility at cern. Resonance parameters have been extracted up to 5, 3, and 8 keV, respectively, using the sammy code for a full R-matrix fit of the capture yields. From these results average resonance parameters were derived by a statistical analysis to provide a comprehensive experimental basis for modeling of the stellar neutron capture rates of these isotopes in terms of the Hauser-Feshbach statistical model. Consistent calculations for the capture and inelastic reaction channels are crucial for the evaluation of stellar enhancement factors to correct the Maxwellian averaged cross sections obtained from experimental data for the effect of thermally populated excited states. These factors have been calculated for the full temperature range of current scenarios of s-process nucleosynthesis using the combined information of the experimental data in the region of resolved resonances and in the continuum. The consequences of this analysis for the s-process component of the Os187 abundance and the related impact on the evaluation of the time duration of galactic nucleosynthesis via the Re/Os cosmochronometer are discussed.

  2. Neutron physics of the Re/Os clock. II. The (n,n{sup '}) cross section of {sup 187}Os at 30 keV neutron energy

    SciTech Connect

    Mosconi, M.; Heil, M.; Kaeppeler, F.; Plag, R.; Mengoni, A.

    2010-07-15

    The inelastic neutron-scattering cross section of {sup 187}Os has been determined in a time-of-flight experiment at the Karlsruhe 3.7-MV Van de Graaff accelerator. An almost monoenergetic beam of 30-keV neutrons was produced at the threshold of the {sup 7}Li(p,n){sup 7}Be reaction. Information on the inelastic channel is required for reliable calculations of the so-called stellar enhancement factor, by which the laboratory cross section of {sup 187}Os must be corrected in order to account for the thermal population of low-lying excited states at the temperatures of s-process nucleosynthesis, in particular of the important state at 9.75 keV. This correction represents a crucial step in the interpretation of the {sup 187}Os/{sup 187}Re pair as a cosmochronometer.

  3. Photodisintegration cross section measurements on {sup 186}W, {sup 187}Re, and {sup 188}Os: Implications for the Re-Os cosmochronology

    SciTech Connect

    Shizuma, T.; Utsunomiya, H.; Goko, S.; Makinaga, A.; Akimune, H.; Yamagata, T.; Ohta, M.; Mohr, P.; Hayakawa, T.; Ohgaki, H.; Lui, Y.-W.; Toyokawa, H.; Uritani, A.; Goriely, S.

    2005-08-01

    Cross sections of the {sup 186}W, {sup 187}Re, {sup 188}Os({gamma},n) reactions were measured using quasimonochromatic photon beams from laser Compton scattering with average energies from 7.3 to 10.9 MeV. The results are compared with the predictions of Hauser-Feshbach statistical calculations using four different sets of input parameters. In addition, the inverse neutron capture cross sections were evaluated by constraining the model parameters, especially the E1 strength function, on the basis of the experimental data. The present experiment helps to further constrain the correction factor F{sub {sigma}} for the neutron capture on the 9.75 keV state in {sup 187}Os. Implications of F{sub {sigma}} for the Re-Os cosmochronology are discussed with a focus on the uncertainty in the estimate of the age of the galaxy.

  4. Platinum group elements and 187Os/ 188Os in a purported impact ejecta layer near the Eifelian-Givetian stage boundary, Middle Devonian

    NASA Astrophysics Data System (ADS)

    Schmitz, Birger; Ellwood, Brooks B.; Peucker-Ehrenbrink, Bernhard; El Hassani, Ahmed; Bultynck, Pierre

    2006-09-01

    A global faunal crisis close to the Eifelian-Givetian stage boundary in the mid-Devonian has been purported to be related to the impact of one or two major extraterrestrial bodies. This was based on unusual mineralogical and chemical features within a distinct composite marl bed, at a level c. 40 cm below the Global Stratotype Section and Point (GSSP) for the Eifelian-Givetian boundary at Jebel Mech Irdane in Morocco. The impact relation has been challenged based partly on the absence of platinum group element data. We present here detailed Ir, Os, Pd and Pt as well as Os isotopic data across the bed at Mech Irdane and from a correlated 10 cm bed at a nearby site, Rich Haroun. Iridium concentrations of 0.13-0.28 ng/g in the beds represent a small enrichment compared to average shale, but Ir/Al ratios are only a factor 1.5-2 higher than background at respective site. Such small enrichments can readily be explained by terrestrial diagenetic processes, and do not require the presence of an extraterrestrial component. On an Al-normalized basis Pd and Pt show weak enrichments, typically a factor 2-4 higher than background. High 187Os/ 188Os ratios, 1.1-3.8, reflect ingrowth of radiogenic Os from Re, which is also evident from Os concentrations of up to 3 ng/g. The platinum group inter-element ratios are clearly non-chondritic. The overall platinum group and trace element (e.g. Co, Ni, As, V) patterns indicate that diagenetic processes at redox fronts have played a crucial role in shaping most element enrichments. If an excess siderophile-rich extraterrestrial component exists in these beds it represents less than 0.2‰ by weight.

  5. OsAUX1 controls lateral root initiation in rice (Oryza sativa L.).

    PubMed

    Zhao, Heming; Ma, Tengfei; Wang, Xin; Deng, Yingtian; Ma, Haoli; Zhang, Rongsheng; Zhao, Jie

    2015-11-01

    Polar auxin transport, mediated by influx and efflux transporters, controls many aspects of plant growth and development. The auxin influx carriers in Arabidopsis have been shown to control lateral root development and gravitropism, but little is known about these proteins in rice. This paper reports on the functional characterization of OsAUX1. Three OsAUX1 T-DNA insertion mutants and RNAi knockdown transgenic plants reduced lateral root initiation compared with wild-type (WT) plants. OsAUX1 overexpression plants exhibited increased lateral root initiation and OsAUX1 was highly expressed in lateral roots and lateral root primordia. Similarly, the auxin reporter, DR5-GUS, was expressed at lower levels in osaux1 than in the WT plants, which indicated that the auxin levels in the mutant roots had decreased. Exogenous 1-naphthylacetic acid (NAA) treatment rescued the defective phenotype in osaux1-1 plants, whereas indole-3-acetic acid (IAA) and 2,4-D could not, which suggested that OsAUX1 was a putative auxin influx carrier. The transcript levels of several auxin signalling genes and cell cycle genes significantly declined in osaux1, hinting that the regulatory role of OsAUX1 may be mediated by auxin signalling and cell cycle genes. Overall, our results indicated that OsAUX1 was involved in polar auxin transport and functioned to control auxin-mediated lateral root initiation in rice.

  6. OsGRF4 controls grain shape, panicle length and seed shattering in rice

    PubMed Central

    Sun, Pingyong; Zhang, Wuhan; Wang, Yihua; He, Qiang; Shu, Fu; Liu, Hai; Wang, Jie; Wang, Jianmin; Yuan, Longping

    2016-01-01

    Abstract Traits such as grain shape, panicle length and seed shattering, play important roles in grain yield and harvest. In this study, the cloning and functional analysis of PANICLE TRAITS 2 (PT2), a novel gene from the Indica rice Chuandali (CDL), is reported. PT2 is synonymous with Growth‐Regulating Factor 4 (OsGRF4), which encodes a growth‐regulating factor that positively regulates grain shape and panicle length and negatively regulates seed shattering. Higher expression of OsGRF4 is correlated with larger grain, longer panicle and lower seed shattering. A unique OsGRF4 mutation, which occurs at the OsmiRNA396 target site of OsGRF4, seems to be associated with high levels of OsGRF4 expression, and results in phenotypic difference. Further research showed that OsGRF4 regulated two cytokinin dehydrogenase precursor genes (CKX5 and CKX1) resulting in increased cytokinin levels, which might affect the panicle traits. High storage capacity and moderate seed shattering of OsGRF4 may be useful in high‐yield breeding and mechanized harvesting of rice. Our findings provide additional insight into the molecular basis of panicle growth. PMID:26936408

  7. Resolvase OsGEN1 Mediates DNA Repair by Homologous Recombination1[OPEN

    PubMed Central

    Lu, Pingli

    2017-01-01

    Yen1/GEN1 are canonical Holliday junction resolvases that belong to the RAD2/XPG family. In eukaryotes, such as budding yeast, mice, worms, and humans, Yen1/GEN1 work together with Mus81-Mms4/MUS81-EME1 and Slx1-Slx4/SLX1-SLX4 in DNA repair by homologous recombination to maintain genome stability. In plants, the biological function of Yen1/GEN1 remains largely unclear. In this study, we characterized the loss of function mutants of OsGEN1 and OsSEND1, a pair of paralogs of Yen1/GEN1 in rice (Oryza sativa). We first investigated the role of OsGEN1 during meiosis and found a reduction in chiasma frequency by ∼6% in osgen1 mutants, compared to the wild type, suggesting a possible involvement of OsGEN1 in the formation of crossovers. Postmeiosis, OsGEN1 foci were detected in wild-type microspore nuclei, but not in the osgen1 mutant concomitant with an increase in double-strand breaks. Persistent double-strand breaks led to programmed cell death of the male gametes and complete male sterility. In contrast, depletion of OsSEND1 had no effects on plant development and did not enhance osgen1 defects. Our results indicate that OsGEN1 is essential for homologous recombinational DNA repair at two stages of microsporogenesis in rice. PMID:28049740

  8. Divergent evolution and molecular adaptation in the Drosophila odorant-binding protein family: inferences from sequence variation at the OS-E and OS-F genes

    PubMed Central

    2008-01-01

    Background The Drosophila Odorant-Binding Protein (Obp) genes constitute a multigene family with moderate gene number variation across species. The OS-E and OS-F genes are the two phylogenetically closest members of this family in the D. melanogaster genome. In this species, these genes are arranged in the same genomic cluster and likely arose by tandem gene duplication, the major mechanism proposed for the origin of new members in this olfactory-system family. Results We have analyzed the genomic cluster encompassing OS-E and OS-F genes (Obp83 genomic region) to determine the role of the functional divergence and molecular adaptation on the Obp family size evolution. We compared nucleotide and amino acid variation across 18 Drosophila and 4 mosquito species applying a phylogenetic-based maximum likelihood approach complemented with information of the OBP three-dimensional structure and function. We show that, in spite the OS-E and OS-F genes are currently subject to similar and strong selective constraints, they likely underwent divergent evolution. Positive selection was likely involved in the functional diversification of new copies in the early stages after the gene duplication event; moreover, it might have shaped nucleotide variation of the OS-E gene concomitantly with the loss of functionally related members. Besides, molecular adaptation likely affecting the functional OBP conformational changes was supported by the analysis of the evolution of physicochemical properties of the OS-E protein and the location of the putative positive selected amino acids on the OBP three-dimensional structure. Conclusion Our results support that positive selection was likely involved in the functional differentiation of new copies of the OBP multigene family in the early stages after their birth by gene duplication; likewise, it might shape variation of some members of the family concomitantly with the loss of functionally related genes. Thus, the stochastic gene gain

  9. Synthesis of 4H/fcc-Au@M (M = Ir, Os, IrOs) Core-Shell Nanoribbons For Electrocatalytic Oxygen Evolution Reaction.

    PubMed

    Fan, Zhanxi; Luo, Zhimin; Chen, Ye; Wang, Jie; Li, Bing; Zong, Yun; Zhang, Hua

    2016-08-01

    The high-yield synthesis of 4H/face-centered cubic (fcc)-Au@Ir core-shell nanoribbons (NRBs) is achieved via the direct growth of Ir on 4H Au NRBs under ambient conditions. Importantly, this method can be used to synthesize 4H/fcc-Au@Os and 4H/fcc-Au@IrOs core-shell NRBs. Significantly, the obtained 4H/fcc-Au@Ir core-shell NRBs demonstrate an exceptional electrocatalytic activity toward the oxygen evolution reaction under acidic condition, which is much higher than that of the commercial Ir/C catalyst.

  10. Fractionation of highly siderophile elements in refertilized mantle: Implications for the Os isotope composition of basalts

    NASA Astrophysics Data System (ADS)

    Marchesi, Claudio; Dale, Christopher W.; Garrido, Carlos J.; Pearson, D. Graham; Bosch, Delphine; Bodinier, Jean-Louis; Gervilla, Fernando; Hidas, Károly

    2014-08-01

    Highly fertile lherzolite and spinel websterite in the Ronda peridotite massif are enriched in Pt and Pd compared to Os, Ir, Ru and Re. The fractionation of the highly siderophile elements (HSE) in these rocks was produced by reaction of melt with their peridotite and pyroxenite precursors. Modeling indicates that upon reaction primary HSE hosts were dissolved and magmatic sulphides precipitated, largely erasing the original HSE signature of reacting protoliths. The budget of HSE in the melt was controlled by sulphide-silicate partitioning or entrainment of molten sulphide in silicate melt. Rhenium was likely removed from precursor peridotite and pyroxenite by previous melt extraction. Refertilization of peridotite by melts increased Al2O3, CaO, Pt, Pd contents and 187Os/188Os beyond typical values for mantle peridotite and the primitive upper mantle. The interaction of melts with residual peridotite and pyroxenite, as illustrated in the Ronda massif, can generate radiogenic-Os-enriched domains in the mantle with high melt productivity, higher Pt/Os and Pt/Re than common peridotite, and lower Re/Os than typical pyroxenite. As also previously proposed for pyroxenites, these “hybrid” domains can account for the difference in Os isotope compositions between many basalts (e.g., MORB and OIB) and common depleted mantle peridotites. Moreover, the presence of these enriched hybrid components in the mantle, evolved over sufficient timescales and in geologically reasonable proportions, may account for the 186Os-187Os enrichment of plume lavas without requiring a chemical contribution from the core.

  11. Os isotope evidence for a differentiated plume head reservoir for the Ontong Java Nui source

    NASA Astrophysics Data System (ADS)

    Schaefer, B. F.; Hoernle, K.; Parkinson, I. J.; Golowin, R.; Portnyagin, M.; Turner, S.; Werner, R.

    2015-12-01

    Previous Os isotopic investigations of lavas from the Ontong Java Plateau1 observed that geographically widely dispersed samples of differing chemistries preserved an isochron of 123±8 Ma with an initial 187Os/188Os = 0.1289±0.0095. Samples from the Manihiki Plateau, itself a portion of the greater Ontong Java Nui (OJN) magmatic event, preserve a far greater range in Os isotopic signatures than previously reported for the OJP alone. In contrast to the OJP data which points towards a near-chondritic, primitive mantle source for both Kroenke and Kwambaita lavas, the low Ti Manihiki samples preserve 187Os/188Os(i) ranging from 0.1056-0.1714. High Ti Manihiki samples preserve 187Os/188Os(i) = 0.1094-0.1288. Such strongly subchondritic signatures require some component of recycled material in the mantle source, possibly SCLM (TRD low Ti samples ~3.1Ga; and ~2.3-2.6Ga for the high Ti samples). Higher initial Os isotope ratios could indicate the presence of metasomatised lithosphere and/or lower crust. The low Ti samples from Manihiki have been interpreted as the result of a two stage melting process, analogous to boninites2, the depleted source of which has itself been metasomatised by a HIMU component entrained within the plume head. Collectively the Ontong Java and Manihiki samples could conceivably contain mantle sourced from both an undifferentiated, near-chondritic source, as well as ancient, unradiogenic recycled sources. Thus the greater OJN province samples a heterogeneous source containing both primitive and recycled components. It is probable that greater degress of partial melting beneath Ontong Java homogenised these heterogeneities, whereas more complex, multi stage melting processes near the plume margin at Manihiki allowed sampling of the inherent heterogeneities within the plume head. 1: Parkinson et al., 2002, GCA 66(15A) A580. 2: Golowin et al., in prep.

  12. Phosphorescence quenching by mechanical stimulus in CaZnOS:Cu

    SciTech Connect

    Tu, Dong; Kamimura, Sunao; Xu, Chao-Nan; Fujio, Yuki; Sakata, Yoshitaro; Ueno, Naohiro

    2014-07-07

    We have found that phosphorescence intensity of CaZnOS:Cu decreased visibly under an applied load. This mechanical quenching (MQ) of phosphorescence in CaZnOS:Cu corresponded to the mechanical stimuli. We have thus demonstrated that the MQ of CaZnOS:Cu could be used for visualizing stress distributions in practical applications. We propose that MQ arises from non-radiative recombination due to electron-transfer from trap levels to non-radiative centers as a result of the mechanical load.

  13. The Rice Monovalent Cation Transporter OsHKT2;4: Revisited Ionic Selectivity1[W

    PubMed Central

    Sassi, Ali; Mieulet, Delphine; Khan, Imran; Moreau, Bertrand; Gaillard, Isabelle; Sentenac, Hervé; Véry, Anne-Aliénor

    2012-01-01

    The family of plant membrane transporters named HKT (for high-affinity K+ transporters) can be subdivided into subfamilies 1 and 2, which, respectively, comprise Na+-selective transporters and transporters able to function as Na+-K+ symporters, at least when expressed in yeast (Saccharomyces cerevisiae) or Xenopus oocytes. Surprisingly, a subfamily 2 member from rice (Oryza sativa), OsHKT2;4, has been proposed to form cation/K+ channels or transporters permeable to Ca2+ when expressed in Xenopus oocytes. Here, OsHKT2;4 functional properties were reassessed in Xenopus oocytes. A Ca2+ permeability through OsHKT2;4 was not detected, even at very low external K+ concentration, as shown by highly negative OsHKT2;4 zero-current potential in high Ca2+ conditions and lack of sensitivity of OsHKT2;4 zero-current potential and conductance to external Ca2+. The Ca2+ permeability previously attributed to OsHKT2;4 probably resulted from activation of an endogenous oocyte conductance. OsHKT2;4 displayed a high permeability to K+ compared with that to Na+ (permeability sequence: K+ > Rb+ ≈ Cs+ > Na+ ≈ Li+ ≈ NH4+). Examination of OsHKT2;4 current sensitivity to external pH suggested that H+ is not significantly permeant through OsHKT2;4 in most physiological ionic conditions. Further analyses in media containing both Na+ and K+ indicated that OsHKT2;4 functions as K+-selective transporter at low external Na+, but transports also Na+ at high (>10 mm) Na+ concentrations. These data identify OsHKT2;4 as a new functional type in the K+ and Na+-permeable HKT transporter subfamily. Furthermore, the high permeability to K+ in OsHKT2;4 supports the hypothesis that this system is dedicated to K+ transport in the plant. PMID:22773759

  14. OsPEX11, a Peroxisomal Biogenesis Factor 11, Contributes to Salt Stress Tolerance in Oryza sativa

    PubMed Central

    Cui, Peng; Liu, Hongbo; Islam, Faisal; Li, Lan; Farooq, Muhammad A.; Ruan, Songlin; Zhou, Weijun

    2016-01-01

    Peroxisomes are single membrane-bound organelles, whose basic enzymatic constituents are catalase and H2O2-producing flavin oxidases. Previous reports showed that peroxisome is involved in numerous processes including primary and secondary metabolism, plant development and abiotic stress responses. However, knowledge on the function of different peroxisome genes from rice and its regulatory roles in salt and other abiotic stresses is limited. Here, a novel prey protein, OsPEX11 (Os03g0302000), was screened and identified by yeast two-hybrid and GST pull-down assays. Phenotypic analysis of OsPEX11 overexpression seedlings demonstrated that they had better tolerance to salt stress than wild type (WT) and OsPEX11-RNAi seedlings. Compared with WT and OsPEX11-RNAi seedlings, overexpression of OsPEX11 had lower level of lipid peroxidation, Na+/K+ ratio, higher activities of antioxidant enzymes (SOD, POD, and CAT) and proline accumulation. Furthermore, qPCR data suggested that OsPEX11 acted as a positive regulator of salt tolerance by reinforcing the expression of several well-known rice transporters (OsHKT2;1, OsHKT1;5, OsLti6a, OsLti6b, OsSOS1, OsNHX1, and OsAKT1) involved in Na+/K+ homeostasis in transgenic plants under salinity. Ultrastructural observations of OsPEX11-RNAi seedlings showed that they were less sensitive to salt stress than WT and overexpression lines. These results provide experimental evidence that OsPEX11 is an important gene implicated in Na+ and K+ regulation, and plays a critical role in salt stress tolerance by modulating the expression of cation transporters and antioxidant defense. Thus, OsPEX11 could be considered in transgenic breeding for improvement of salt stress tolerance in rice crop. PMID:27695459

  15. Homologous U-box E3 Ubiquitin Ligases OsPUB2 and OsPUB3 Are Involved in the Positive Regulation of Low Temperature Stress Response in Rice (Oryza sativa L.).

    PubMed

    Byun, Mi Young; Cui, Li Hua; Oh, Tae Kyung; Jung, Ye-Jin; Lee, Andosung; Park, Ki Youl; Kang, Bin Goo; Kim, Woo Taek

    2017-01-01

    Rice U-box E3 Ub ligases (OsPUBs) are implicated in biotic stress responses. However, their cellular roles in response to abiotic stress are poorly understood. In this study, we performed functional analyses of two homologous OsPUB2 and OsPUB3 in response to cold stress (4°C). OsPUB2 was up-regulated by high salinity, drought, and cold, whereas OsPUB3 was constitutively expressed. A subcellular localization assay revealed that OsPUB2 and OsPUB3 were localized to the exocyst positive organelle (EXPO)-like punctate structures. OsPUB2 was also localized to the nuclei. OsPUB2 and OsPUB3 formed a hetero-dimeric complex as well as homo-dimers in yeast cells and in vitro. OsPUB2/OsPUB3 exhibited self-ubiquitination activities in vitro and were rapidly degraded in the cell-free extracts with apparent half-lives of 150-160 min. This rapid degradation of OsPUB2/OsPUB3 was delayed in the presence of the crude extracts of cold-treated seedlings (apparent half-lives of 200-280 min). Moreover, a hetero-dimeric form of OsPUB2/OsPUB3 was more stable than the homo-dimers. These results suggested that OsPUB2 and OsPUB3 function coordinately in response to cold stress. OsPUB2- and OsPUB3-overexpressing transgenic rice plants showed markedly better tolerance to cold stress than did the wild-type plants in terms of survival rates, chlorophyll content, ion leakage, and expression levels of cold stress-inducible marker genes. Taken together, these results suggested that the two homologous rice U-box E3 Ub ligases OsPUB2 and OsPUB3 are positive regulators of the response to cold stress.

  16. Homologous U-box E3 Ubiquitin Ligases OsPUB2 and OsPUB3 Are Involved in the Positive Regulation of Low Temperature Stress Response in Rice (Oryza sativa L.)

    PubMed Central

    Byun, Mi Young; Cui, Li Hua; Oh, Tae Kyung; Jung, Ye-Jin; Lee, Andosung; Park, Ki Youl; Kang, Bin Goo; Kim, Woo Taek

    2017-01-01

    Rice U-box E3 Ub ligases (OsPUBs) are implicated in biotic stress responses. However, their cellular roles in response to abiotic stress are poorly understood. In this study, we performed functional analyses of two homologous OsPUB2 and OsPUB3 in response to cold stress (4°C). OsPUB2 was up-regulated by high salinity, drought, and cold, whereas OsPUB3 was constitutively expressed. A subcellular localization assay revealed that OsPUB2 and OsPUB3 were localized to the exocyst positive organelle (EXPO)-like punctate structures. OsPUB2 was also localized to the nuclei. OsPUB2 and OsPUB3 formed a hetero-dimeric complex as well as homo-dimers in yeast cells and in vitro. OsPUB2/OsPUB3 exhibited self-ubiquitination activities in vitro and were rapidly degraded in the cell-free extracts with apparent half-lives of 150–160 min. This rapid degradation of OsPUB2/OsPUB3 was delayed in the presence of the crude extracts of cold-treated seedlings (apparent half-lives of 200–280 min). Moreover, a hetero-dimeric form of OsPUB2/OsPUB3 was more stable than the homo-dimers. These results suggested that OsPUB2 and OsPUB3 function coordinately in response to cold stress. OsPUB2- and OsPUB3-overexpressing transgenic rice plants showed markedly better tolerance to cold stress than did the wild-type plants in terms of survival rates, chlorophyll content, ion leakage, and expression levels of cold stress-inducible marker genes. Taken together, these results suggested that the two homologous rice U-box E3 Ub ligases OsPUB2 and OsPUB3 are positive regulators of the response to cold stress. PMID:28163713

  17. iOS--Worthy of the Hype as Assistive Technology for Visual Impairments? A Phenomenological Study of iOS Device Use by Individuals with Visual Impairments

    ERIC Educational Resources Information Center

    Scott, Shari

    2013-01-01

    This qualitative study sought to explore the shared essence of the lived experiences of early adopters of iOS devices as assistive technology by persons with visual impairments. The capstone question addressed the idea of whether any one device could fully meet the assistive technology needs of this population. Purposeful sampling methods were…

  18. Rice phytochrome-interacting factor protein OsPIF14 represses OsDREB1B gene expression through an extended N-box and interacts preferentially with the active form of Phytochrome B

    PubMed Central

    Cordeiro, André M.; Figueiredo, Duarte D.; Tepperman, James; Borba, Ana Rita; Lourenço, Tiago; Abreu, Isabel A.; Ouwerkerk, Pieter B.F.; Quail, Peter H.; Oliveira, M. Margarida; Saibo, Nelson J. M.

    2016-01-01

    DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a Yeast one Hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bind to hexameric E-box (CANNTG) or N-box (CACG(A/C)G) motifs, depending on transcriptional activity. We have shown that OsPIF14 binds to the OsDREB1B promoter through two N-boxes and that the flanking regions of the hexameric core are essential for protein-DNA interaction and stability. We also showed that OsPIF14 down-regulates OsDREB1B gene expression in rice protoplasts, corroborating the OsPIF14 repressor activity observed in the transactivation assays using Arabidopsis protoplasts. In addition, we showed that OsPIF14 is indeed a Phytochrome Interacting Factor, which preferentially binds to the active form (Pfr) of rice phytochrome B. This raises the possibility that OsPIF14 activity might be modulated by light. However, we did not observe any regulation of the OsDREB1B gene expression by light under control conditions. Moreover, OsPIF14 gene expression was shown to be modulated by different treatments, such as drought, salt, cold and ABA. Interestingly, OsPIF14 showed also a specific cold-induced alternative splicing. All together, these results suggest the possibility that OsPIF14 is involved in cross-talk between light and stress signaling through interaction with the OsDREB1B promoter. Although in the absence of stress, OsDREB1B gene expression was not regulated by light, given previous reports, it remains possible that OsPIF14 has a role in light modulation of stress responses. PMID:26732823

  19. Rice phytochrome-interacting factor protein OsPIF14 represses OsDREB1B gene expression through an extended N-box and interacts preferentially with the active form of phytochrome B

    DOE PAGES

    Cordeiro, André M.; Figueiredo, Duarte D.; Tepperman, James; ...

    2015-12-28

    DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a yeast one-hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bind to hexameric E-box (CANNTG) or N-box (CACG(A/C)G) motifs, depending on transcriptional activity. We have shown that OsPIF14 binds to the OsDREB1B promoter through two N-boxes and that the flanking regions of the hexameric core are essential for protein–DNA interaction and stability. We also showed that OsPIF14 down-regulates OsDREB1B gene expression in rice protoplasts, corroborating the OsPIF14 repressormore » activity observed in the transactivation assays using Arabidopsis protoplasts. Additionally, we showed that OsPIF14 is indeed a phytochrome interacting factor, which preferentially binds to the active form (Pfr) of rice phytochrome B. This raises the possibility that OsPIF14 activity might be modulated by light. However, we did not observe any regulation of the OsDREB1B gene expression by light under control conditions. Moreover, OsPIF14 gene expression was shown to be modulated by different treatments, such as drought, salt, cold and ABA. Interestingly, OsPIF14 showed also a specific cold-induced alternative splicing. Our results suggest the possibility that OsPIF14 is involved in cross-talk between light and stress signaling through interaction with the OsDREB1B promoter. Finally, although in the absence of stress, OsDREB1B gene expression was not regulated by light, given previous reports, it remains possible that OsPIF14 has a role in light modulation of stress responses.« less

  20. Rice phytochrome-interacting factor protein OsPIF14 represses OsDREB1B gene expression through an extended N-box and interacts preferentially with the active form of phytochrome B.

    PubMed

    Cordeiro, André M; Figueiredo, Duarte D; Tepperman, James; Borba, Ana Rita; Lourenço, Tiago; Abreu, Isabel A; Ouwerkerk, Pieter B F; Quail, Peter H; Margarida Oliveira, M; Saibo, Nelson J M

    2016-02-01

    DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a yeast one-hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bind to hexameric E-box (CANNTG) or N-box (CACG(A/C)G) motifs, depending on transcriptional activity. We have shown that OsPIF14 binds to the OsDREB1B promoter through two N-boxes and that the flanking regions of the hexameric core are essential for protein-DNA interaction and stability. We also showed that OsPIF14 down-regulates OsDREB1B gene expression in rice protoplasts, corroborating the OsPIF14 repressor activity observed in the transactivation assays using Arabidopsis protoplasts. In addition, we showed that OsPIF14 is indeed a phytochrome interacting factor, which preferentially binds to the active form (Pfr) of rice phytochrome B. This raises the possibility that OsPIF14 activity might be modulated by light. However, we did not observe any regulation of the OsDREB1B gene expression by light under control conditions. Moreover, OsPIF14 gene expression was shown to be modulated by different treatments, such as drought, salt, cold and ABA. Interestingly, OsPIF14 showed also a specific cold-induced alternative splicing. All together, these results suggest the possibility that OsPIF14 is involved in cross-talk between light and stress signaling through interaction with the OsDREB1B promoter. Although in the absence of stress, OsDREB1B gene expression was not regulated by light, given previous reports, it remains possible that OsPIF14 has a role in light modulation of stress responses.

  1. Rice phytochrome-interacting factor protein OsPIF14 represses OsDREB1B gene expression through an extended N-box and interacts preferentially with the active form of phytochrome B

    SciTech Connect

    Cordeiro, André M.; Figueiredo, Duarte D.; Tepperman, James; Borba, Ana Rita; Lourenço, Tiago; Abreu, Isabel A.; Ouwerkerk, Pieter B. F.; Quail, Peter H.; Margarida Oliveira, M.; Saibo, Nelson J. M.

    2015-12-28

    DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a yeast one-hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bind to hexameric E-box (CANNTG) or N-box (CACG(A/C)G) motifs, depending on transcriptional activity. We have shown that OsPIF14 binds to the OsDREB1B promoter through two N-boxes and that the flanking regions of the hexameric core are essential for protein–DNA interaction and stability. We also showed that OsPIF14 down-regulates OsDREB1B gene expression in rice protoplasts, corroborating the OsPIF14 repressor activity observed in the transactivation assays using Arabidopsis protoplasts. Additionally, we showed that OsPIF14 is indeed a phytochrome interacting factor, which preferentially binds to the active form (Pfr) of rice phytochrome B. This raises the possibility that OsPIF14 activity might be modulated by light. However, we did not observe any regulation of the OsDREB1B gene expression by light under control conditions. Moreover, OsPIF14 gene expression was shown to be modulated by different treatments, such as drought, salt, cold and ABA. Interestingly, OsPIF14 showed also a specific cold-induced alternative splicing. Our results suggest the possibility that OsPIF14 is involved in cross-talk between light and stress signaling through interaction with the OsDREB1B promoter. Finally, although in the absence of stress, OsDREB1B gene expression was not regulated by light, given previous reports, it remains possible that OsPIF14 has a role in light modulation of stress responses.

  2. Nanoscale variations in 187Os isotopic composition and HSE systematics in a Bultfontein peridotite

    NASA Astrophysics Data System (ADS)

    Wainwright, A. N.; Luguet, A.; Schreiber, A.; Fonseca, R. O. C.; Nowell, G. M.; Lorand, J.-P.; Wirth, R.; Janney, P. E.

    2016-08-01

    Understanding the mineralogical controls on radiogenic chronometers is a fundamental aspect of all geochronological tools. As with other common dating tools, it has become increasingly clear that the Re-Os system can be impacted by multiple mineral formation events. The accessory and micrometric nature of the Re-Os-bearing minerals has made assessing this influence complex. This is especially evident in cratonic peridotites, where long residence times and multiple metasomatic events have created a complex melting and re-enrichment history. Here we investigate a harzburgitic peridotite from the Bultfontein kimberlite (South Africa) which contains sub-micron Pt-Fe-alloy inclusions within base metal sulphides (BMS). Through the combination of the focused ion beam lift-out technique and low blank mass spectrometry we were able to remove and analyse the Pt-Fe-alloy inclusions for their Re-Os composition and highly siderophile element (HSE) systematics. Six repeats of the whole-rock yield 187Os/188Os compositions of 0.10893-0.10965, which correspond to Re depletion model ages (TRD) of 2.69-2.79 Ga. The Os, Ir and Pt concentrations are slightly variable across the different digestions, whilst Pd and Re remain constant. The resulting HSE pattern is typical of cratonic peridotites displaying depleted Pt and Pd. The Pt-Fe-alloys have PUM-like 187Os/188Os compositions of 0.1294 ± 24 (2-s.d.) and 0.1342 ± 38, and exhibit a saw-tooth HSE pattern with enriched Re and Pt. In contrast, their BMS hosts have unradiogenic 187Os/188Os of 0.1084 ± 6 and 0.1066 ± 3, with TRD ages of 2.86 and 3.09 Ga, similar to the whole-rock systematics. The metasomatic origin of the BMS is supported by (i) the highly depleted nature of the mantle peridotite and (ii) their Ni-rich sulphide assemblage. Occurrence of Pt-Fe-alloys as inclusions within BMS grains demonstrates the genetic link between the BMS and Pt-Fe-alloys and argues for formation during a single but continuous event of silicate melt

  3. Os isotopes in SNC meteorites and their implications to the early evolution of Mars and Earth

    NASA Technical Reports Server (NTRS)

    Jagoutz, E.; Luck, J. M.; Othman, D. Ben; Wanke, H.

    1993-01-01

    A new development on the measurement of the Os isotopic composition by mass spectrometry using negative ions opened a new field of applications. The Re-Os systematic provides time information on the differentiation of the nobel metals. The nobel metals are strongly partitioned into metal and sulphide phases, but also the generation of silicate melts might fractionate the Re-Os system. Compared to the other isotopic systems which are mainly dating the fractionation of the alkalis and alkali-earth elements, the Re-Os system is expected to disclose entirely new information about the geochemistry. Especially the differentiation and early evolution of the planets such as the formation of the core will be elucidated with this method.

  4. Intraarticular Entrapment of Os Subfibulare Following a Severe Inversion Injury of the Ankle: A Case Report

    PubMed Central

    Kose, Ozkan; Kilicaslan, Omer Faruk; Guler, Ferhat; Aktan, Cemil

    2015-01-01

    Introduction: Anterior Talofibular Ligament (ATFL) rupture is the most commonly injured anatomic structure in lateral ankle sprain. In some cases, ATFL avulsion fracture from the lateral malleolus may occur instead of purely ligamentous injuries. The ATFL avulsion fracture is detected as a small ossicle at the tip of lateral malleolus on direct radiographs, which is called os subfibulare in chronic cases. Case Presentation: Severe displacement of this ossicle to the tibiotalar joint space is an extremely rare injury. Herein, a case of intra-articular entrapment of os subfibulare following a severe inversion injury of the ankle, which caused a diagnostic challenge was presented. Conclusions: To the best of our knowledge, this is the first case of entrapment of os subfibulare in the talotibial joint space. Fixation of the os subfibulare to lateral malleolus resulted in union and excellent functional results. PMID:26101763

  5. Structure of the OsSERK2 leucine-rich repeat extracellular domain

    PubMed Central

    McAndrew, Ryan; Pruitt, Rory N.; Kamita, Shizuo G.; Pereira, Jose Henrique; Majumdar, Dipali; Hammock, Bruce D.; Adams, Paul D.; Ronald, Pamela C.

    2014-01-01

    Somatic embryogenesis receptor kinases (SERKs) are leucine-rich repeat (LRR)-containing integral membrane receptors that are involved in the regulation of development and immune responses in plants. It has recently been shown that rice SERK2 (OsSERK2) is essential for XA21-mediated resistance to the pathogen Xanthomonas oryzae pv. oryzae. OsSERK2 is also required for the BRI1-mediated, FLS2-mediated and EFR-mediated responses to brassinosteroids, flagellin and elongation factor Tu (EF-Tu), respectively. Here, crystal structures of the LRR domains of OsSERK2 and a D128N OsSERK2 mutant, expressed as hagfish variable lymphocyte receptor (VLR) fusions, are reported. These structures suggest that the aspartate mutation does not generate any significant conformational change in the protein, but instead leads to an altered interaction with partner receptors. PMID:25372696

  6. Structure of the OsSERK2 leucine-rich repeat extracellular domain.

    PubMed

    McAndrew, Ryan; Pruitt, Rory N; Kamita, Shizuo G; Pereira, Jose Henrique; Majumdar, Dipali; Hammock, Bruce D; Adams, Paul D; Ronald, Pamela C

    2014-11-01

    Somatic embryogenesis receptor kinases (SERKs) are leucine-rich repeat (LRR)-containing integral membrane receptors that are involved in the regulation of development and immune responses in plants. It has recently been shown that rice SERK2 (OsSERK2) is essential for XA21-mediated resistance to the pathogen Xanthomonas oryzae pv. oryzae. OsSERK2 is also required for the BRI1-mediated, FLS2-mediated and EFR-mediated responses to brassinosteroids, flagellin and elongation factor Tu (EF-Tu), respectively. Here, crystal structures of the LRR domains of OsSERK2 and a D128N OsSERK2 mutant, expressed as hagfish variable lymphocyte receptor (VLR) fusions, are reported. These structures suggest that the aspartate mutation does not generate any significant conformational change in the protein, but instead leads to an altered interaction with partner receptors.

  7. The flavonoid luteolin enhances doxorubicin-induced autophagy in human osteosarcoma U2OS cells

    PubMed Central

    Zhang, Baoliang; Yu, Xin; Xia, Hong

    2015-01-01

    Luteolin (LUT), a flavone, which is universally present as constituent of medicinal plants as well as some vegetables and spices, has been demonstrated display specific anti-carcinogenic effects. However, the mechanisms by which LUT inhibits human osteosarcoma growth remain unknown. The effects of LUT on cell growth in human osteosarcoma U2OS cells were measured by MTT assay and flowcytometry. The effects of LUT on morphological markers of autophagy in U2OS were analyzed by fluorescence microscopy and electron microscopy. Autophagic markers, beclin1 and LC3 were detected by western blotting. Here, we found that LUT induced autophagy in U2OS and acted as an enhancer to sensitize doxorubicin (DOX)-mediated autophagy signaling. The combined treatment of LUT and DOX greatly decreases the growth of U2OS, showing synergistic cytotoxicity. Our results indicate that LUT in combination with DOX maybe a novel strategy for the treatment of human osteosarcoma. PMID:26629003

  8. Characterization and molecular cloning of a serine hydroxymethyltransferase 1 (OsSHM1) in rice.

    PubMed

    Wang, Dekai; Liu, Heqin; Li, Sujuan; Zhai, Guowei; Shao, Jianfeng; Tao, Yuezhi

    2015-09-01

    Serine hydroxymethyltransferase (SHMT) is important for one carbon metabolism and photorespiration in higher plants for its participation in plant growth and development, and resistance to biotic and abiotic stresses. A rice serine hydroxymethyltransferase gene, OsSHM1, an ortholog of Arabidopsis SHM1, was isolated using map-based cloning. The osshm1 mutant had chlorotic lesions and a considerably smaller, lethal phenotype under natural ambient CO2 concentrations, but could be restored to wild type with normal growth under elevated CO2 levels (0.5% CO2 ), showing a typical photorespiratory phenotype. The data from antioxidant enzymes activity measurement suggested that osshm1 was subjected to significant oxidative stress. Also, OsSHM1 was expressed in all organs tested (root, culm, leaf, and young panicle) but predominantly in leaves. OsSHM1 protein is localized to the mitochondria. Our study suggested that molecular function of the OsSHM1 gene is conserved in rice and Arabidopsis.

  9. Bug-Free Sensors: The Automatic Verification of Context-Aware TinyOS Applications

    NASA Astrophysics Data System (ADS)

    Bucur, Doina; Kwiatkowska, Marta

    We provide the first tool for verifying the logic of context-aware applications written for the mainstream sensor network operating system TinyOS; we focus on detecting programming errors related to incorrect adaptation to context.

  10. Chemical and physical parameters affecting the performance of the Os-191/Ir-191m generator

    SciTech Connect

    Packard, A.B.; Treves, S.; O'Brien, G.M.; Knapp, F.F. Jr.; Butler, T.A.

    1984-01-01

    The development of an Os-191/Ir-191m generator suitable for radionuclide angiography in humans has elicited much interest. This generator employs (OsO/sub 2/Cl/sub 4/)/sup 2 -/ on AG MP-1 anion exchange resin with a Dowex-2 scavenger column and is elute with normal saline at pH 1. The parent Os species is, however, neither well-defined nor homogeneous leading to less than optimal breakthrough of Os-191 (5 x 10/sup -3/%) and modest Ir-191m yield (10-15%). The effect of a range of parameters on generator performance has been evaluated as has been the way in which the assembly and loading process affects generator performance. In addition, a number of potential alternative generator systems have been evaluated. 11 references, 2 figures, 8 tables.

  11. Novel high pressure hexagonal OsB{sub 2} by mechanochemistry

    SciTech Connect

    Xie, Zhilin; Graule, Moritz; Orlovskaya, Nina; Andrew Payzant, E.; Cullen, David A.; Blair, Richard G.

    2014-07-01

    Hexagonal OsB{sub 2}, a theoretically predicted high-pressure phase, has been synthesized for the first time by a mechanochemical method, i.e., high energy ball milling. X-ray diffraction indicated that formation of hexagonal OsB{sub 2} begins after 2.5 h of milling, and the reaction reaches equilibrium after 18 h of milling. Rietveld refinement of the powder data indicated that hexagonal OsB{sub 2} crystallizes in the P63/mmc space group (No. 194) with lattice parameters of a=2.916 Å and c=7.376 Å. Transmission electron microscopy confirmed the appearance of the hexagonal OsB{sub 2} phase after high energy ball milling. in situ X-ray diffraction experiments showed that the phase is stable from −225 °C to 1050 °C. The hexagonal OsB{sub 2} powder was annealed at 1050 °C for 6 days in vacuo to improve crystallinity and remove strain induced during the mechanochemical synthesis. The structure partially converted to the orthorhombic phase (20 wt%) after fast current assisted sintering of hexagonal OsB{sub 2} at 1500 °C for 5 min. Mechanochemical approaches to the synthesis of hard boride materials allow new phases to be produced that cannot be prepared using conventional methods. - Graphical abstract: High resolution transmission electron micrograph of hexagonal OsB{sub 2} nanocrystallite with corresponding fast Fourier transform and simulated diffraction pattern. - Highlights: • Hexagonal OsB{sub 2} has been synthesized for the first time by mechanochemical method. • Hexagonal OsB{sub 2} crystallizes in P63/mmc space group (No. 194), a=2.916 Å and c=7.376 Å. • The hexagonal structure was confirmed by a transmission electron microscope. • No phase transformation was observed after being annealed at 1050 °C for 6 days. • 20 wt% of h-OsB{sub 2} was transformed to o-OsB{sub 2} after being sintered at 1500 °C for 5 min.

  12. Hydrocarbon Maturation and Os Mixing on Bolide Impact at the Frasnian-Famennian Boundary

    NASA Astrophysics Data System (ADS)

    Stein, H.; Zimmerman, A.; Yang, G.; Hannah, J.; Egenhoff, S.

    2009-04-01

    An intractable problem in the application of Re-Os geochemistry has been knowledge of the distribution of Re and Os between source rock and generated hydrocarbon. Solutions lie in combined experimental work with controlled and induced maturation, and field studies optimized by known source rock and time of hydrocarbon generation. The Siljan impact site with its variably tilted but largely intact Ordovician-Silurian sections provides an unsurpassed opportunity to examine the Re-Os systematics of source rock and generated crude oil, and the Re-Os imprint of the bolide. This three-component system contains (1) a time pin for maturation (377 ± 2 Ma; laser argon dating of impact melt, Reimold et al. 2005) arguably at the Frasnian-Famennian boundary, (2) known source rocks with kerogens still intact, and (3) crude oils generated on impact. Modeling takes into consideration the possibility of pre-impact maturation as well. At Siljan, numerous quarries expose the Upper Ordovician Boda and Kullsberg limestone mounds, and locally, the underlying and laterally equivalent Tretaspis (Fjäcka) shale. We obtained a sample of crude oil seeping from a drill hole in the quarry floor at Solberga. Preliminary Re-Os analyses on four aliquots of this oil form an excellent linear array in 187Re/188Os versus 187Os/188Os space. The associated age, however, is impossibly old (Neoproterozoic), and the initial 187Os/188Os unreasonably low (0.2). Rather, this linear array fits a mixing line between a meteoritic component and a hydrocarbon generated from the Tretaspis shale. We are presently performing further tests to isolate the two end-members. Filtering suggests that the extraterrestrial component consists of small physical particles which can be largely removed from the petroleum fraction. The extreme contrast in Re-Os composition between meteorite (known) and black shale (in progress) end-members maximizes the sensitivity of the isotopic study. Reimold, W.U., Kelley, S.P., Sherlock, S

  13. OsCHX14 is Involved in the K+ Homeostasis in Rice (Oryza sativa) Flowers.

    PubMed

    Chen, Yi; Ma, Jingkun; Miller, Anthony J; Luo, Bingbing; Wang, Mei; Zhu, Zhen; Ouwerkerk, Pieter B F

    2016-07-01

    Previously we showed in the osjar1 mutants that the lodicule senescence which controls the closing of rice flowers was delayed. This resulted in florets staying open longer when compared with the wild type. The gene OsJAR1 is silenced in osjar1 mutants and is a key member of the jasmonic acid (JA) signaling pathway. We found that K concentrations in lodicules and flowers of osjar1-2 were significantly elevated compared with the wild type, indicating that K(+) homeostasis may play a role in regulating the closure of rice flowers. The cation/H(+) exchanger (CHX) family from rice was screened for potential K(+) transporters involved as many members of this family in Arabidopsis were exclusively or preferentially expressed in flowers. Expression profiling confirmed that among 17 CHX genes in rice, OsCHX14 was the only member that showed an expression polymorphism, not only in osjar1 mutants but also in RNAi (RNA interference) lines of OsCOI1, another key member of the JA signaling pathway. This suggests that the expression of OsCHX14 is regulated by the JA signaling pathway. Green fluorescent protein (GFP)-tagged OsCHX14 protein was preferentially localized to the endoplasmic reticulum. Promoter-β-glucuronidase (GUS) analysis of transgenic rice revealed that OsCHX14 is mainly expressed in lodicules and the region close by throughout the flowering process. Characterization in yeast and Xenopus laevis oocytes verified that OsCHX14 is able to transport K(+), Rb(+) and Cs(+) in vivo. Our data suggest that OsCHX14 may play an important role in K(+) homeostasis during flowering in rice.

  14. OsHV-1 countermeasures to the Pacific oyster's anti-viral response.

    PubMed

    Green, Timothy J; Rolland, Jean-Luc; Vergnes, Agnes; Raftos, David; Montagnani, Caroline

    2015-11-01

    The host-pathogen interactions between the Pacific oyster (Crassostrea gigas) and Ostreid herpesvirus type 1 (OsHV-1) are poorly characterised. Herpesviruses are a group of large, DNA viruses that are known to encode gene products that subvert their host's antiviral response. It is likely that OsHV-1 has also evolved similar strategies as its genome encodes genes with high homology to C. gigas inhibitors of apoptosis (IAPs) and an interferon-stimulated gene (termed CH25H). The first objective of this study was to simultaneously investigate the expression of C. gigas and OsHV-1 genes that share high sequence homology during an acute infection. Comparison of apoptosis-related genes revealed that components of the extrinsic apoptosis pathway (TNF) were induced in response to OsHV-1 infection, but we failed to observe evidence of apoptosis using a combination of biochemical and molecular assays. IAPs encoded by OsHV-1 were highly expressed during the acute stage of infection and may explain why we didn't observe evidence of apoptosis. However, C. gigas must have an alternative mechanism to apoptosis for clearing OsHV-1 from infected gill cells as we observed a reduction in viral DNA between 27 and 54 h post-infection. The reduction of viral DNA in C. gigas gill cells occurred after the up-regulation of interferon-stimulated genes (viperin, PKR, ADAR). In a second objective, we manipulated the host's anti-viral response by injecting C. gigas with a small dose of poly I:C at the time of OsHV-1 infection. This small dose of poly I:C was unable to induce transcription of known antiviral effectors (ISGs), but these oysters were still capable of inhibiting OsHV-1 replication. This result suggests dsRNA induces an anti-viral response that is additional to the IFN-like pathway.

  15. A rice ABC transporter, OsABCC1, reduces arsenic accumulation in the grain

    PubMed Central

    Song, Won-Yong; Yamaki, Tomohiro; Yamaji, Naoki; Ko, Donghwi; Jung, Ki-Hong; Fujii-Kashino, Miho; An, Gynheung; Martinoia, Enrico; Lee, Youngsook; Ma, Jian Feng

    2014-01-01

    Arsenic (As) is a chronic poison that causes severe skin lesions and cancer. Rice (Oryza sativa L.) is a major dietary source of As; therefore, reducing As accumulation in the rice grain and thereby diminishing the amount of As that enters the food chain is of critical importance. Here, we report that a member of the Oryza sativa C-type ATP-binding cassette (ABC) transporter (OsABCC) family, OsABCC1, is involved in the detoxification and reduction of As in rice grains. We found that OsABCC1 was expressed in many organs, including the roots, leaves, nodes, peduncle, and rachis. Expression was not affected when plants were exposed to low levels of As but was up-regulated in response to high levels of As. In both the basal nodes and upper nodes, which are connected to the panicle, OsABCC1 was localized to the phloem region of vascular bundles. Furthermore, OsABCC1 was localized to the tonoplast and conferred phytochelatin-dependent As resistance in yeast. Knockout of OsABCC1 in rice resulted in decreased tolerance to As, but did not affect cadmium toxicity. At the reproductive growth stage, the As content was higher in the nodes and in other tissues of wild-type rice than in those of OsABCC1 knockout mutants, but was significantly lower in the grain. Taken together, our results indicate that OsABCC1 limits As transport to the grains by sequestering As in the vacuoles of the phloem companion cells of the nodes in rice. PMID:25331872

  16. Os and U-Th isotope signatures of arc magmatism near Mount Mazama, Crater Lake, Oregon

    NASA Astrophysics Data System (ADS)

    Ankney, Meagan E.; Shirey, Steven B.; Hart, Garret L.; Bacon, Charles R.; Johnson, Clark M.

    2016-03-01

    Interaction of mantle melts with the continental crust can have significant effects on the composition of the resulting melts as well as on the crust itself, and tracing this interaction is key to our understanding of arc magmatism. Lava flows and pyroclastic deposits erupted from ∼50 to 7.7 ka at Mt. Mazama (Crater Lake, Oregon) were analyzed for their Re/Os and U-Th isotopic compositions. Mafic lavas from monogenetic vents around Mt. Mazama that erupted during the buildup to its climactic eruption have lower 187Os/188Os ratios (0.1394 to 0.1956) and high 230Th excess ((230Th/238U)0 of 1.180 to 1.302), whereas dacites and rhyodacites tend to have higher 187Os/188Os ratios (0.2292 to 0.2788) and significant 238U excess ((230Th/238U)0 of 0.975 to 0.989). The less radiogenic Os isotope compositions of the mafic lavas can be modeled by assimilation of young (∼2.5 to 7 Ma), mafic lower crust that was modified during regional extension, whereas the more radiogenic Os isotope compositions of the dacites and rhyodacites can be attributed to assimilation of older (∼10 to 16 Ma), mid to upper crust that acquired its composition during an earlier period of Cascade magmatism. Production of Th excesses in the lower crust requires very young garnet formation accompanying dehydration melting in the lower crust at less than a few 100 ka by heat from recent basaltic magma injection. The results from this study suggest that the combination of Os and Th isotopes may be used to provide insights into the timescales of evolution of the continental crust in arc settings, as well as the influence of the crust on erupted magmas, and suggest a link between the age and composition of the lower and upper crust to regional tectonic extension and/or earlier Cascade magmatism.

  17. A rice ABC transporter, OsABCC1, reduces arsenic accumulation in the grain.

    PubMed

    Song, Won-Yong; Yamaki, Tomohiro; Yamaji, Naoki; Ko, Donghwi; Jung, Ki-Hong; Fujii-Kashino, Miho; An, Gynheung; Martinoia, Enrico; Lee, Youngsook; Ma, Jian Feng

    2014-11-04

    Arsenic (As) is a chronic poison that causes severe skin lesions and cancer. Rice (Oryza sativa L.) is a major dietary source of As; therefore, reducing As accumulation in the rice grain and thereby diminishing the amount of As that enters the food chain is of critical importance. Here, we report that a member of the Oryza sativa C-type ATP-binding cassette (ABC) transporter (OsABCC) family, OsABCC1, is involved in the detoxification and reduction of As in rice grains. We found that OsABCC1 was expressed in many organs, including the roots, leaves, nodes, peduncle, and rachis. Expression was not affected when plants were exposed to low levels of As but was up-regulated in response to high levels of As. In both the basal nodes and upper nodes, which are connected to the panicle, OsABCC1 was localized to the phloem region of vascular bundles. Furthermore, OsABCC1 was localized to the tonoplast and conferred phytochelatin-dependent As resistance in yeast. Knockout of OsABCC1 in rice resulted in decreased tolerance to As, but did not affect cadmium toxicity. At the reproductive growth stage, the As content was higher in the nodes and in other tissues of wild-type rice than in those of OsABCC1 knockout mutants, but was significantly lower in the grain. Taken together, our results indicate that OsABCC1 limits As transport to the grains by sequestering As in the vacuoles of the phloem companion cells of the nodes in rice.

  18. High-pressure crystal growth and electromagnetic properties of 5d double-perovskite Ca₃OsO₆

    SciTech Connect

    Feng, Hai Luke; Shi, Youguo; Guo, Yanfeng; Li, Jun; Sato, Akira; Sun, Ying; Wang, Xia; Yu, Shan; Sathish, Clastin I.; Yamaura, Kazunari

    2013-05-01

    Single crystals of the osmium-containing compound Ca₃OsO₆ have been successfully grown under high-pressure conditions, for the first time. The crystal structure of Ca₃OsO₆ atoms being fully ordered at the perovskite B-site. The electromagnetic analysis shows that the crystal exhibits a semiconductor-like behavior below 300 K and undergoes an antiferromagnetic transition at 50 K. - Graphical Abstract: Schematic image of crystal structure of Ca₃OsO₆ as determined by X-ray diffraction, where the gray and black octahedrons are occupied by Ca and Os, respectively. Top inset reveals an optic image of a typical Ca₃OsO₆ single crystal. Highlights: • Single crystals of Ca₃OsO₆ have been successfully grown under high-pressure. • Ca₃OsO₆ crystalizes into an ordered double-perovskite structure. • The Ca₃OsO₆ undergoes an antiferromagnetic transition at 50 K.

  19. The Os isotopic variation of abyssal peridotites revised: A study from the ultra-slow spreading Gakkel Ridge

    NASA Astrophysics Data System (ADS)

    Büchl, A.; Snow, J. E.

    2003-04-01

    It is generally thought that the Os isotopic variation of abyssal peridotites (187Os/188Os varies from 0.120 to 0.129 after [1,2,3,4]) only exceeds the chondritic value of 0.127 [5] because of secondary alteration by seawater. In contrast supra-chondritic 187Os/188Os ratios in peridotites from ophiolites [6] and xenoliths from a subduction zone setting [7] have been ascribed to exchange of Os with radiogenic melts. We analysed the Os isotopic composition of 16 peridotites from the ultra-slow spreading Gakkel Ridge. The samples are unusually fresh for abyssal peridotites. The Os isotopic composition varies from 0.1208 to 0.1344 in the spinel-lherzolites, from 0.1176 to 0.1360 in the harzburgites and from 0.1325 to 0.1400 in the dunites. The reason for the supra-chondritic Os isotopic ratios could be (a) secondary alteration by seawater, (b) radiogenic ingrowth due to the decay of Re to Os, or (c) exchange with a radiogenic magmatic component. The fact that the degree of alteration does not correlate with Os isotopic composition, together with the high Os concentration in the peridotites compared with seawater, implies that the supra-chondritic 187Os/188Os ratios cannot be explained by secondary alteration processes. The similar and low Re and high Os concentrations in all samples rule out the ingrowth of 187Os as source for the supra-chondritic values. World-wide volcanic rocks mostly have supra-chondritic 187Os/188Os ratios. In addition it was shown recently that during melt percolation the peridotites can inherit the signature of percolating melts [6]. This suggests that the supra-chondritic 187Os/188Os ratios are due to the exchange with a magmatic component. This is supported by the observation that the dunites, which are expected to have the highest melt/rock ratio of all lithologies, have the most radiogenic signatures. We therefore suggest that the 187Os/188Os variation of abyssal peridotites is much larger than previously considered. However the origin of

  20. A rice tonoplastic calcium exchanger, OsCCX2 mediates Ca2+/cation transport in yeast

    PubMed Central

    Yadav, Akhilesh K.; Shankar, Alka; Jha, Saroj K.; Kanwar, Poonam; Pandey, Amita; Pandey, Girdhar K.

    2015-01-01

    In plant cell, cations gradient in cellular compartments is maintained by synergistic action of various exchangers, pumps and channels. The Arabidopsis exchanger family members (AtCCX3 and AtCCX5) were previously studied and belong to CaCA (calcium cation exchangers) superfamily while none of the rice CCXs has been functionally characterized for their cation transport activities till date. Rice genome encode four CCXs and only OsCCX2 transcript showed differential expression under abiotic stresses and Ca2+ starvation conditions. The OsCCX2 localized to tonoplast and suppresses the Ca2+ sensitivity of K667 (low affinity Ca2+ uptake deficient) yeast mutant under excess CaCl2 conditions. In contrast to AtCCXs, OsCCX2 expressing K667 yeast cells show tolerance towards excess Na+, Li+, Fe2+, Zn2+ and Co2+ and suggest its ability to transport both mono as well as divalent cations in yeast. Additionally, in contrast to previously characterized AtCCXs, OsCCX2 is unable to complement yeast trk1trk2 double mutant suggesting inability to transport K+ in yeast system. These finding suggest that OsCCX2 having distinct metal transport properties than previously characterized plant CCXs. OsCCX2 can be used as potential candidate for enhancing the abiotic stress tolerance in plants as well as for phytoremediation of heavy metal polluted soil. PMID:26607171

  1. Re-Os dating of maltenes and asphaltenes within single samples of crude oil

    NASA Astrophysics Data System (ADS)

    Georgiev, Svetoslav V.; Stein, Holly J.; Hannah, Judith L.; Galimberti, Roberto; Nali, Micaela; Yang, Gang; Zimmerman, Aaron

    2016-04-01

    Re-Os geochronology of oil may constrain the timing of oil formation and improve oil-source and oil-oil correlations. Typically, asphaltene (ASPH), the heaviest and most Re-Os rich oil fraction, from multiple oils within an oil field or a larger petroleum system are analyzed to obtain sufficient spread in Re-Os isotopic ratios, a mathematical necessity for precise Re-Os isochrons. Here we offer a new approach for Re-Os geochronology of oil based on isotopic analyses of different fractions within a single sample of crude oil. We studied three oils from the Gela oil field, southern Sicily, Italy, recovered from Triassic-Jurassic stratigraphic intervals (Streppenosa, Noto, and Sciacca Formations) within the Gela-1 well. ASPH (insoluble in n-alkane) and maltene (MALT, soluble in n-alkane) fractions of oil were separated using n-pentane, n-hexane, n-heptane and n-decane solvents. The ASPH contents of the Sciacca and Noto oils (26-33 wt%) are notably higher compared to the Streppenosa oil (7-12 wt% ASPH). We present an optimized Re-Os procedure with sample digestion in a high-pressure asher, followed by isotopic measurements using negative thermal ionization mass spectrometry. Very high metal contents of Gela oils allowed acquisition of precise Re-Os data. Systematic variations between the type of solvent used for ASPH precipitation and the ASPH content of the oil (also known from the literature) and the Re-Os contents of the ASPH and MALT fractions (first observed in this study) provide important practical applications for Re-Os analyses of oil. Most Re and Os (∼96-98%) in the Noto oil are hosted in the ASPH fraction. In contrast, a significant portion of Re and Os (∼33-34%) is stored in the MALT fraction of the lighter, but heavily biodegraded Streppenosa oil. Collectively, our new data on alkane distribution, hopane and sterane biomarkers, major and trace element contents, and Re-Os concentrations and isotopic ratios of the oils and their fractions support the

  2. CrxOS maintains the self-renewal capacity of murine embryonic stem cells

    SciTech Connect

    Saito, Ryota; Yamasaki, Tokiwa; Nagai, Yoko; Wu, Jinzhan; Kajiho, Hiroaki; Yokoi, Tadashi; Noda, Eiichiro; Nishina, Sachiko; Niwa, Hitoshi; Azuma, Noriyuki; Katada, Toshiaki; Nishina, Hiroshi

    2009-12-25

    Embryonic stem (ES) cells maintain pluripotency by self-renewal. Several homeoproteins, including Oct3/4 and Nanog, are known to be key factors in maintaining the self-renewal capacity of ES cells. However, other genes required for the mechanisms underlying this process are still unclear. Here we report the identification by in silico analysis of a homeobox-containing gene, CrxOS, that is specifically expressed in murine ES cells and is essential for their self-renewal. ES cells mainly express the short isoform of endogenous CrxOS. Using a polyoma-based episomal expression system, we demonstrate that overexpression of the CrxOS short isoform is sufficient for maintaining the undifferentiated morphology of ES cells and stimulating their proliferation. Finally, using RNA interference, we show that CrxOS is essential for the self-renewal of ES cells, and provisionally identify foxD3 as a downstream target gene of CrxOS. To our knowledge, ours is the first delineation of the physiological role of CrxOS in ES cells.

  3. Re-Os geochronology and Os isotope fingerprinting of petroleum sourced from a Type I lacustrine kerogen: insights from the natural Green River petroleum system in the Uinta Basin and hydrous pyrolysis experiments

    USGS Publications Warehouse

    Cumming, Vivien M.; Selby, David; Lillis, Paul G.; Lewan, Michael D.

    2014-01-01

    Rhenium–osmium (Re–Os) geochronology of marine petroleum systems has allowed the determination of the depositional age of source rocks as well as the timing of petroleum generation. In addition, Os isotopes have been applied as a fingerprinting tool to correlate oil to its source unit. To date, only classic marine petroleum systems have been studied. Here we present Re–Os geochronology and Os isotope fingerprinting of different petroleum phases (oils, tar sands and gilsonite) derived from the lacustrine Green River petroleum system in the Uinta Basin, USA. In addition we use an experimental approach, hydrous pyrolysis experiments, to compare to the Re–Os data of naturally generated petroleum in order to further understand the mechanisms of Re and Os transfer to petroleum. The Re–Os geochronology of petroleum from the lacustrine Green River petroleum system (19 ± 14 Ma – all petroleum phases) broadly agrees with previous petroleum generation basin models (∼25 Ma) suggesting that Re–Os geochronology of variable petroleum phases derived from lacustrine Type I kerogen has similar systematics to Type II kerogen (e.g., Selby and Creaser, 2005a, Selby and Creaser, 2005b and Finlay et al., 2010). However, the large uncertainties (over 100% in some cases) produced for the petroleum Re–Os geochronology are a result of multiple generation events occurring through a ∼3000-m thick source unit that creates a mixture of initial Os isotope compositions in the produced petroleum phases. The 187Os/188Os values for the petroleum and source rocks at the time of oil generation vary from 1.4 to 1.9, with the mode at ∼1.6. Oil-to-source correlation using Os isotopes is consistent with previous correlation studies in the Green River petroleum system, and illustrates the potential utility of Os isotopes to characterize the spatial variations within a petroleum system. Hydrous pyrolysis experiments on the Green River Formation source rocks show that Re and Os transfer

  4. OsSpo11-4, a rice homologue of the archaeal TopVIA protein, mediates double-strand DNA cleavage and interacts with OsTopVIB.

    PubMed

    An, Xiao Jing; Deng, Zhu Yun; Wang, Tai

    2011-01-01

    DNA topoisomerase VI from Archaea, a heterotetrameric complex composed of two TopVIA and two TopVIB subunits, is involved in altering DNA topology during replication, transcription and chromosome segregation by catalyzing DNA strand transfer through transient double-strand breaks. The sequenced yeast and animal genomes encode only one homologue of the archaeal TopVIA subunit, namely Spo11, and no homologue of the archaeal TopVIB subunit. In yeast, Spo11 is essential for initiating meiotic recombination and this function appears conserved among other eukaryotes. In contrast to yeast and animals, studies in Arabidopsis and rice have identified three Spo11/TopVIA homologues and one TopVIB homologue in plants. Here, we further identified two novel Spo11/TopVIA homologues (named OsSpo11-4 and OsSpo11-5, respectively) that exist just in the monocot model plant Oryza sativa, indicating that at least five Spo11/TopVIA homologues are present in the rice genome. To reveal the biochemical function of the two novel Spo11/TopVIA homologues, we first examined the interactions among OsSpo11-1, OsSpo11-4, OsSpo11-5, and OsTopVIB by yeast two-hybrid assay. The results showed that OsSpo11-4 and OsTopVIB can self-interact strongly and among the 3 examined OsSpo11 proteins, only OsSpo11-4 interacted with OsTopVIB. Pull-down assay confirmed the interaction between OsSpo11-4 and OsTopVIB, which indicates that OsSpo11-4 may interact with OsTopVIB in vivo. Further in vitro enzymatic analysis revealed that among the above 4 proteins, only OsSpo11-4 exhibited double-strand DNA cleavage activity and its enzymatic activity appears dependent on Mg(2+) and independent of OsTopVIB, despite its interaction with OsTopVIB. We further analyzed the biological function of OsSpo11-4 by RNA interference and found that down-regulated expression of OsSpo11-4 led to defects in male meiosis, indicating OsSpo11-4 is required for meiosis.

  5. Probing the links between structure and magnetism in Sr(2-x)Ca(x)FeOsO₆ double perovskites.

    PubMed

    Morrow, Ryan; Freeland, John W; Woodward, Patrick M

    2014-08-04

    The synthesis, structure, and properties of the ordered double perovskites Sr2FeOsO6, Ca2FeOsO6, and SrCaFeOsO6 are reported. The latter two compounds have monoclinic P2₁/n symmetry and a(-)a(-)b(+) tilting of the octahedra, while Sr2FeOsO6 is tetragonal with I4/m symmetry and a(0)a(0)c(-) tilting. Magnetic measurements indicate and neutron powder diffraction studies confirm that Ca2FeOsO6 is a ferrimagnet with a Curie temperature of 350 K. The ferrimagnetism is retained if half of the Ca(2+) ions are replaced with larger Sr(2+) ions to form SrCaFeOsO6 (T(C) = 210 K). This substitution reduces the degree of octahedral tilting, but unlike most perovskites, the magnetic ordering temperature decreases as the Fe-O-Os bond angles approach a linear geometry. In contrast, Sr2FeOsO6 orders antiferromagnetically, as previously reported. X-ray absorption spectroscopy confirms the assignment of Fe(III) and Os(V) oxidation states for all three compounds. In these insulating double perovskites, the magnetic ground state is governed by a competition between the four-bond Fe-O-Os-O-Fe antiferromagnetic superexchange coupling of Fe(III) ions and the two-bond Fe-O-Os antiferromagnetic superexchange coupling between neighboring Fe(III) and Os(V) ions. When the Fe-O-Os bonds are linear, as they are in the c direction in Sr2FeOsO6, the four-bond coupling between Fe(III) ions prevails. The competition shifts in favor of antiferromagnetic coupling of Fe(III) and Os(V) as the Fe-O-Os bond angles bend in response to chemical pressure.

  6. K{sub 2}NaOsO{sub 5.5} and K{sub 3}NaOs{sub 2}O{sub 9}: The first osmium perovskites containing alkali cations at the 'A' site

    SciTech Connect

    Mogare, Kailash M.; Klein, Wilhelm; Jansen, Martin

    2012-07-15

    K{sub 2}NaOsO{sub 5.5} and K{sub 3}NaOs{sub 2}O{sub 9} were obtained from solid-state reactions of potassium superoxide, sodium peroxide and osmium metal at elevated oxygen pressures. K{sub 2}NaOsO{sub 5.5} crystallizes as an oxygen-deficient cubic double perovskite in space group Fm3{sup Macron }m with a=8.4184(5) A and contains isolated OsO{sub 6} octahedra. K{sub 3}NaOs{sub 2}O{sub 9} crystallizes hexagonally in P6{sub 3}/mmc with a=5.9998(4) A and c=14.3053(14) A. K{sub 3}NaOs{sub 2}O{sub 9} consists of face sharing Os{sub 2}O{sub 9} pairs of octahedra. According to magnetic measurements K{sub 2}NaOsO{sub 5.5} is diamagnetic, whereas K{sub 3}NaOs{sub 2}O{sub 9} displays strong antiferromagnetic coupling (T{sub N}=140 K), indicating enhanced magnetic interactions within the octahedral pair. - Graphical abstract: High oxidation states of Os, obtained by high oxygen pressure synthesis, are accommodated in double and triple perovskite matrices. K{sub 3}NaOs{sub 2}O{sub 9} displays enhanced magnetic interactions. Highlights: Black-Right-Pointing-Pointer New osmates containing highly oxidized Os were obtained by high O{sub 2} pressure synthesis. Black-Right-Pointing-Pointer High oxidation states of Os are accommodated in double and triple perovskite matrices. Black-Right-Pointing-Pointer Both compounds represent the first Os perovskites with an alkali metal at the A site. Black-Right-Pointing-Pointer K{sub 3}NaOs{sub 2}O{sub 9} displays enhanced magnetic interactions within the octahedral pair.

  7. CONSTANS-Like 9 (OsCOL9) Interacts with Receptor for Activated C-Kinase 1(OsRACK1) to Regulate Blast Resistance through Salicylic Acid and Ethylene Signaling Pathways.

    PubMed

    Liu, Hao; Dong, Shuangyu; Sun, Dayuan; Liu, Wei; Gu, Fengwei; Liu, Yongzhu; Guo, Tao; Wang, Hui; Wang, Jiafeng; Chen, Zhiqiang

    2016-01-01

    In a previous transcriptome analysis of early response genes in rice during Magnaporthe oryzae infection, we identified a CONSTANS-like (COL) gene OsCOL9. In the present study, we investigated the functional roles of OsCOL9 in blast resistance. OsCOL9 belonged to group II of the COL protein family, and it contained a BB-box and a C-terminal CCT (CONSTANS, COL and TOC1) domain. OsCOL9 was found in the nucleus of rice cells, and it exerted transcriptional activation activities through its middle region (MR). Magnaporthe oryzae infection induced OsCOL9 expression, and transgenic OsCOL9 knock-out rice plants showed increased pathogen susceptibility. OsCOL9 was a critical regulator of pathogen-related genes, especially PR1b, which were also activated by exogenous salicylic acid (SA) and 1-aminocyclopropane-1-carboxylicacid (ACC), the precursor of ethylene (ET). Further analysis indicated that OsCOL9 over-expression increased the expressions of phytohormone biosynthetic genes, NPR1, WRKY45, OsACO1 and OsACS1, which were related to SA and ET biosynthesis. Interestingly, we found that OsCOL9 physically interacted with the scaffold protein OsRACK1 through its CCT domain, and the OsRACK1 expression was induced in response to exogenous SA and ACC as well as M. oryzae infection. Taken together, these results indicated that the COL protein OsCOL9 interacted with OsRACK1, and it enhanced the rice blast resistance through SA and ET signaling pathways.

  8. CONSTANS-Like 9 (OsCOL9) Interacts with Receptor for Activated C-Kinase 1(OsRACK1) to Regulate Blast Resistance through Salicylic Acid and Ethylene Signaling Pathways

    PubMed Central

    Dong, Shuangyu; Sun, Dayuan; Liu, Wei; Gu, Fengwei; Liu, Yongzhu; Guo, Tao; Wang, Hui; Wang, Jiafeng; Chen, Zhiqiang

    2016-01-01

    In a previous transcriptome analysis of early response genes in rice during Magnaporthe oryzae infection, we identified a CONSTANS-like (COL) gene OsCOL9. In the present study, we investigated the functional roles of OsCOL9 in blast resistance. OsCOL9 belonged to group II of the COL protein family, and it contained a BB-box and a C-terminal CCT (CONSTANS, COL and TOC1) domain. OsCOL9 was found in the nucleus of rice cells, and it exerted transcriptional activation activities through its middle region (MR). Magnaporthe oryzae infection induced OsCOL9 expression, and transgenic OsCOL9 knock-out rice plants showed increased pathogen susceptibility. OsCOL9 was a critical regulator of pathogen-related genes, especially PR1b, which were also activated by exogenous salicylic acid (SA) and 1-aminocyclopropane-1-carboxylicacid (ACC), the precursor of ethylene (ET). Further analysis indicated that OsCOL9 over-expression increased the expressions of phytohormone biosynthetic genes, NPR1, WRKY45, OsACO1 and OsACS1, which were related to SA and ET biosynthesis. Interestingly, we found that OsCOL9 physically interacted with the scaffold protein OsRACK1 through its CCT domain, and the OsRACK1 expression was induced in response to exogenous SA and ACC as well as M. oryzae infection. Taken together, these results indicated that the COL protein OsCOL9 interacted with OsRACK1, and it enhanced the rice blast resistance through SA and ET signaling pathways. PMID:27829023

  9. 32 CFR 1630.17 - Class 1-O-S: Conscientious objector to all military service (separated).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Class 1-O-S: Conscientious objector to all... National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.17 Class 1-O-S: Conscientious... and noncombatant training and service in the Armed Forces shall be classified in Class 1-O-S...

  10. Quantifying Ostreid herpesvirus (OsHV-1) genome copies and expression during transmission.

    PubMed

    Burge, Colleen A; Friedman, Carolyn S

    2012-04-01

    Understanding the pathogenic potential of a new pathogen strain or a known pathogen in a new locale is crucial for management of disease in both wild and farmed animals. The Ostreid herpesvirus-1 (OsHV-1), a known pathogen of early-life-stage Pacific oysters, Crassostrea gigas, has been associated with mortalities of juvenile oysters in many locations around the world including Tomales Bay, California. In two trials, the California OsHV-1 strain was transmitted from infected juvenile C. gigas to naïve C. gigas larvae. Survival of control larvae was high throughout both trials (97-100%) and low among those exposed to OsHV-1. No OsHV-1-exposed larvae survived to day 9 in trial 1, while trial 2 was terminated at day 7 when survival was 36.90 ± 8.66%. To assess the amount of OsHV-1 DNA present, we employed quantitative polymerase chain reaction (qPCR) assays based on the A fragment and OsHV-1 catalytic subunit of a DNA polymerase δ (DNA pol) gene. Viral genome copy numbers based on qPCR assays peaked between 3 and 5 days. To measure the presence of viable and actively transcribing virus, the DNA pol gene qPCR assay was optimized for RNA analysis after being reverse transcribed (RT-qPCR). A decline in virus gene expression was measured using RT-qPCR: relative to earlier experimental time points copy numbers were significantly lower on day 9, trial 1 (p < 0.05) and day 7, trial 2 (p < 0.05). Peaks in copies of active virus per genome occurred during two periods in trial 1 (days 1 and 5/7, p < 0.05) and one period in trial 2 (day 1, p < 0.05). Transmission electron microscopy confirmed OsHV-1 infection; herpesvirus-like nucleocapsids, capsids, and extracellular particles were visualized. We demonstrated the ability to transmit OsHV-1 from infected juvenile oysters to naïve larvae, which indicates the spread of OsHV-1 between infected hosts in the field and between commercial farms is possible. We also developed an important tool (OsHV-1-specific RT-qPCR for an active

  11. Neutron physics of the Re/Os clock. I. Measurement of the (n,gamma) cross sections of {sup 186,187,188}Os at the CERN n{sub T}OF facility

    SciTech Connect

    Mosconi, M.; Kaeppeler, F.; Audouin, L.; Dillmann, I.; Heil, M.; Plag, R.; Voss, F.; Walter, S.; Wisshak, K.; Fujii, K.; Abbondanno, U.; Belloni, F.; Milazzo, P. M.; Moreau, C.; Mengoni, A.; Domingo-Pardo, C.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2010-07-15

    The precise determination of the neutron capture cross sections of {sup 186}Os and {sup 187}Os is important to define the s-process abundance of {sup 187}Os at the formation of the solar system. This quantity can be used to evaluate the radiogenic component of the abundance of {sup 187}Os due to the decay of the unstable {sup 187}Re (t{sub 1/2}=41.2 Gyr) and from this to infer the time duration of the nucleosynthesis in our galaxy (Re/Os cosmochronometer). The neutron capture cross sections of {sup 186}Os, {sup 187}Os, and {sup 188}Os have been measured at the CERN n{sub T}OF facility from 1 eV to 1 MeV, covering the entire energy range of astrophysical interest. The measurement has been performed by time-of-flight technique using isotopically enriched samples and two C{sub 6}D{sub 6} scintillation detectors for recording the prompt gamma rays emitted in the capture events. Maxwellian averaged capture cross sections have been determined for thermal energies between kT=5 and 100 keV corresponding to all possible s-process scenarios. The estimated uncertainties for the values at 30 keV are 4.1, 3.3, and 4.7% for {sup 186}Os, {sup 187}Os, and {sup 188}Os, respectively.

  12. Neutron physics of the Re/Os clock. I. Measurement of the (n,γ) cross sections of Os186,187,188 at the CERN n_TOF facility

    NASA Astrophysics Data System (ADS)

    Mosconi, M.; Fujii, K.; Mengoni, A.; Domingo-Pardo, C.; Käppeler, F.; Abbondanno, U.; Aerts, G.; Álvarez-Pol, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Bisterzo, S.; Calviani, M.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Furman, W.; Gallino, R.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Karamanis, D.; Karadimos, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Massimi, C.; Mastinu, P.; Milazzo, P. M.; Moreau, C.; Neves, F.; Oberhummer, H.; Oshima, M.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2010-07-01

    The precise determination of the neutron capture cross sections of Os186 and Os187 is important to define the s-process abundance of Os187 at the formation of the solar system. This quantity can be used to evaluate the radiogenic component of the abundance of Os187 due to the decay of the unstable Re187 (t1/2=41.2 Gyr) and from this to infer the time duration of the nucleosynthesis in our galaxy (Re/Os cosmochronometer). The neutron capture cross sections of Os186, Os187, and Os188 have been measured at the CERN n_TOF facility from 1 eV to 1 MeV, covering the entire energy range of astrophysical interest. The measurement has been performed by time-of-flight technique using isotopically enriched samples and two C6D6 scintillation detectors for recording the prompt γ rays emitted in the capture events. Maxwellian averaged capture cross sections have been determined for thermal energies between kT=5 and 100 keV corresponding to all possible s-process scenarios. The estimated uncertainties for the values at 30 keV are 4.1, 3.3, and 4.7% for Os186, Os187, and Os188, respectively.

  13. The F-Box Protein OsFBK12 Targets OsSAMS1 for Degradation and Affects Pleiotropic Phenotypes, Including Leaf Senescence, in Rice1[W][OPEN

    PubMed Central

    Chen, Yuan; Xu, Yunyuan; Luo, Wei; Li, Wenxuan; Chen, Na; Zhang, Dajian; Chong, Kang

    2013-01-01

    Leaf senescence is related to the grain-filling rate and grain weight in cereals. Many components involved in senescence regulation at either the genetic or physiological level are known. However, less is known about molecular regulation mechanisms. Here, we report that OsFBK12 (an F-box protein containing a Kelch repeat motif) interacts with S-ADENOSYL-l-METHIONINE SYNTHETASE1 (SAMS1) to regulate leaf senescence and seed size as well as grain number in rice (Oryza sativa). Yeast two-hybrid, pull-down, and bimolecular fluorescence complementation assays indicate that OsFBK12 interacts with Oryza sativa S-PHASE KINASE-ASSOCIATED PROTEIN1-LIKE PROTEIN and with OsSAMS1. Biochemical and physiological data showed that OsFBK12 targets OsSAMS1 for degradation. OsFBK12-RNA interference lines and OsSAMS1 overexpression lines showed increased ethylene levels, while OsFBK12-OX lines and OsSAMS1-RNA interference plants exhibited decreased ethylene. Phenotypically, overexpression of OsFBK12 led to a delay in leaf senescence and germination and increased seed size, whereas knockdown lines of either OsFBK12 or OsSAMS1 promoted the senescence program. Our results suggest that OsFBK12 is involved in the 26S proteasome pathway by interacting with Oryza sativa S-PHASE KINASE-ASSOCIATED PROTEIN1-LIKE PROTEIN and that it targets the substrate OsSAMS1 for degradation, triggering changes in ethylene levels for the regulation of leaf senescence and grain size. These data have potential applications in the molecular breeding of rice. PMID:24144792

  14. Ectopic Expression of OsSta2 Enhances Salt Stress Tolerance in Rice

    PubMed Central

    Kumar, Manu; Choi, Juyoung; An, Gynheung; Kim, Seong-Ryong

    2017-01-01

    Salt stress can severely reduce crop yields. To understand how rice (Oryza sativa) plants respond to this environmental challenge, we investigated the genes involved in conferring salt tolerance by screening T-DNA tagging lines and identified OsSta2-D (Oryza sativa Salt tolerance activation 2-Dominant). In that line, expression of OsSta2 was enhanced by approximately eightfold when compared with the non-transformed wild type (WT). This gene was highly expressed in the callus, roots, and panicles. To confirm its role in stress tolerance, we generated transgenic rice that over-expresses OsSta2 under a maize ubiquitin promoter. The OsSta2-Ox plants were salt-tolerant at the vegetative stage, based on our calculations of chlorophyll fluorescence (Fv/Fm), fresh and dry weights, chlorophyll concentrations, and survival rates. Under normal paddy field conditions, the Ox plants were somewhat shorter than the WT control but had improved agronomic traits such as higher total grain yield. They were also more tolerant to osmotic stress and hypersensitive to abscisic acid. Based on all of these results, we suggest that OsSta2 has important roles in determining yields as well as in conferring tolerance to salt stresses. PMID:28344585

  15. Haemangiosarcoma of the os penis in a dog: The most common neoplasm of the canine penis.

    PubMed

    Burchell, Richard K; Kirberger, Robert M; Janse van Rensberg, Drienie D Didi

    2014-08-21

    A castrated 9-year-old intact male boerboel cross-breed dog was presented with a month-long history of stranguria. On physical examination, a mass was noted at the caudal extremity of the os penis. Haematology, serum chemistry and urinalysis were all unremarkable. Abdominal and urethral ultrasound demonstrated an enlarged bladder and a dilated urethra, which was followed to the caudal extremity of the os penis. A hyperechoic, roughly spherical,vascularised mass was noted at the caudal os penis, which resulted in obstruction of the penile urethra. Radiographs demonstrated a soft tissue mass with osteolysis of the os penis. Cytology suggested an osteosarcoma. Treatment included amputation of the penis and adjuvant doxorubicin with carboplatin. Histopathology of the penis confirmed a haemangiosarcoma. The patient survived for 20 months. This is only the second published case report describing a penile haemangiosarcoma, and the first published report demonstrating the treatment and outcome of a case of haemangiosarcoma of the os penis. Based on published and unpublished reports, haemangiosarcoma appears to be the most common neoplasm of the canine penis.

  16. Oxygen interaction with hexagonal OsB2 at high temperature

    SciTech Connect

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; Cullen, David A.; Kata, Dariusz; Rutkowski, Pawel; Lis, Jerzy; Qin, Nan; T-Raissi, Ali

    2016-08-10

    The stability of ReB2-type hexagonal OsB2 powder at high temperature with oxygen presence has been studied by thermogravimetric analysis, differential scanning calorimetry, SEM, EDS, and high-temperature scanning transmission electron microscopy and XRD. Results of the study revealed that OsB2 ceramics interact readily with oxygen present in reducing atmosphere, especially at high temperature and produces boric acid, which decomposes on the surface of the powder resulting in the formation of boron vacancies in the hexagonal OsB2 lattice as well as changes in the stoichiometry of the compound. It was also found that under low oxygen partial pressure, sintering of OsB2 powders occurred at a relatively low temperature (900°C). Finally, hexagonal OsB2 ceramic is prone to oxidation and it is very sensitive to oxygen partial pressures, especially at high temperatures.

  17. OsABCB14 functions in auxin transport and iron homeostasis in rice (Oryza sativa L.).

    PubMed

    Xu, Yanxia; Zhang, Saina; Guo, Haipeng; Wang, Suikang; Xu, Ligen; Li, Chuanyou; Qian, Qian; Chen, Fan; Geisler, Markus; Qi, Yanhua; Jiang, De An

    2014-07-01

    Members of the ATP Binding Cassette B/Multidrug-Resistance/P-glyco-protein (ABCB/MDR/PGP) subfamily were shown to function primarily in Oryza sativa (rice) auxin transport; however, none of the rice ABCB transporters have been functionally characterized. Here, we describe that a knock-down of OsABCB14 confers decreased auxin concentrations and polar auxin transport rates, conferring insensitivity to 2,4-dichlorophenoxyacetic acid (2,4-D) and indole-3-acetic acid (IAA). OsABCB14 displays enhanced specific auxin influx activity in yeast and protoplasts prepared from rice knock-down alleles. OsABCB14 is localized at the plasma membrane, pointing to an important directionality under physiological conditions. osabcb14 mutants were surprisingly found to be insensitive to iron deficiency treatment (-Fe). Their Fe concentration is higher and upregulation of Fe deficiency-responsive genes is lower in osabcb14 mutants than in wild-type rice (Nipponbare, NIP). Taken together, our results strongly support the role of OsABCB14 as an auxin influx transporter involved in Fe homeostasis. The functional characterization of OsABCB14 provides insights in monocot auxin transport and its relationship to Fe nutrition.

  18. OsFRDL1 is a citrate transporter required for efficient translocation of iron in rice.

    PubMed

    Yokosho, Kengo; Yamaji, Naoki; Ueno, Daisei; Mitani, Namiki; Ma, Jian Feng

    2009-01-01

    Multidrug and toxic compound extrusion (MATE) transporters represent a large family in plants, but their functions are poorly understood. Here, we report the function of a rice (Oryza sativa) MATE gene (Os03g0216700, OsFRDL1), the closest homolog of barley (Hordeum vulgare) HvAACT1 (aluminum [Al]-activated citrate transporter 1), in terms of metal stress (iron [Fe] deficiency and Al toxicity). This gene was mainly expressed in the roots and the expression level was not affected by either Fe deficiency or Al toxicity. Knockout of this gene resulted in leaf chlorosis, lower leaf Fe concentration, higher accumulation of zinc and manganese concentration in the leaves, and precipitation of Fe in the root's stele. The concentration of citrate and ferric iron in the xylem sap was lower in the knockout line compared to the wild-type rice. Heterologous expression of OsFRDL1 in Xenopus oocytes showed transport activity for citrate. Immunostaining showed that OsFRDL1 was localized at the pericycle cells of the roots. On the other hand, there was no difference in the Al-induced secretion of citrate from the roots between the knockout line and the wild-type rice. Taken together, our results indicate that OsFRDL1 is a citrate transporter localized at the pericycle cells, which is necessary for efficient translocation of Fe to the shoot as a Fe-citrate complex.

  19. OsLBD3-7 Overexpression Induced Adaxially Rolled Leaves in Rice

    PubMed Central

    Zhang, Chunyu; Shao, Qinghao; Liu, Jun; Liu, Bin; Li, Hongyu

    2016-01-01

    Appropriate leaf rolling enhances erect-leaf habits and photosynthetic efficiency, which consequently improves grain yield. Here, we reported the novel lateral organ boundaries domain (LBD) gene OsLBD3-7, which is involved in the regulation of leaf rolling. OsLBD3-7 works as a transcription activator and its protein is located on the plasma membrane and in the nucleus. Overexpression of OsLBD3-7 leads to narrow and adaxially rolled leaves. Microscopy of flag leaf cross-sections indicated that overexpression of OsLBD3-7 led to a decrease in both bulliform cell size and number. Transcriptional analysis showed that key genes that had been reported to be negative regulators of bulliform cell development were up-regulated in transgenic plants. These results indicated that OsLBD3-7 might acts as an upstream regulatory gene of bulliform cell development to regulate leaf rolling, which will give more insights on the leaf rolling regulation mechanism. PMID:27258066

  20. OsNRAMP5 contributes to manganese translocation and distribution in rice shoots.

    PubMed

    Yang, Meng; Zhang, Yuanyuan; Zhang, Lejing; Hu, Jintao; Zhang, Xing; Lu, Kai; Dong, Huaxia; Wang, Dujun; Zhao, Fang-Jie; Huang, Chao-Feng; Lian, Xingming

    2014-09-01

    Manganese (Mn) is an essential micronutrient for plants playing an important role in many physiological functions. OsNRAMP5 is a major transporter responsible for Mn and cadmium uptake in rice, but whether it is involved in the root-to-shoot translocation and distribution of these metals is unknown. In this work, OsNRAMP5 was found to be highly expressed in hulls. It was also expressed in leaves but the expression level decreased with leaf age. High-magnification observations revealed that OsNRAMP5 was enriched in the vascular bundles of roots and shoots especially in the parenchyma cells surrounding the xylem. The osnramp5 mutant accumulated significantly less Mn in shoots than the wild-type plants even at high levels of Mn supply. Furthermore, a high supply of Mn could compensate for the loss in the root uptake ability in the mutant, but not in the root-to-shoot translocation of Mn, suggesting that the absence of OsNRAMP5 reduces the transport of Mn from roots to shoots. The results suggest that OsNRAMP5 plays an important role in the translocation and distribution of Mn in rice plants in addition to its role in Mn uptake.

  1. Synthesis, crystal structure, bonding, and properties of (Ba6O)(OsN3)2.

    PubMed

    Schmidt, Carsten L; Wedig, Ulrich; Dinnebier, Robert; Jansen, Martin

    2008-11-13

    The new barium nitridoosmate oxide (Ba(6)O)(OsN(3))(2) was prepared by reacting elemental barium and osmium (3:1) in nitrogen at 815-830 degrees C. The crystal structure of (Ba(6)O)(OsN(3))(2) as determined by laboratory powder X-ray diffraction (R3, No 148: a = b = 8.112(1) A, c = 17.390(1) A, V = 991.0(1) A(3), Z = 3), consists of sheets of trigonal OsN(3) units and trigonal-antiprismatic Ba(6)O groups, and is structurally related to the "313 nitrides" AE(3)MN(3) (AE = Ca, Sr, Ba, M = V-Co, Ga). Density functional calculations, using a hybrid functional, likewise indicate the existence of oxygen in the Ba(6) polyhedra. The oxidation state 4+ of osmium is confirmed, both by the calculations and by XPS measurements. The bonding properties of the OsN(3)(5-) units are analyzed and compared to the Raman spectrum. The compound is paramagnetic from room temperature down to T = 10 K. Between room temperature and 100 K it obeys the Curie-Weiss law (mu = 1.68 mu(B)). (Ba(6)O)(OsN(3))(2) is semiconducting with a good electronic conductivity at room temperature (8.74x10(-2) ohms(-1) cm(-1)). Below 142 K the temperature dependence of the conductivity resembles that of a variable-range hopping mechanism.

  2. Structural and superconducting properties of RbOs2O6 single crystals

    NASA Astrophysics Data System (ADS)

    Rogacki, Krzysztof; Schuck, Götz; Bukowski, Zbigniew; Zhigadlo, Nikolai D.; Karpinski, Janusz

    2008-04-01

    Single crystals of RbOs2O6 have been grown from Rb2O and Os in sealed quartz ampoules. The crystal structure has been identified at room temperature as cubic with the lattice constant a=10.1242(12)Å . The anisotropy of the tetrahedral and octahedral networks is lower and the displacement parameters of alkali metal atoms are smaller than those for KOs2O6 , so the “rattling” of the alkali atoms in RbOs2O6 is less pronounced. The superconducting properties of RbOs2O6 in the mixed state have been described well within the London approach and the Ginzburg Landau parameter κ(0)≅31 has been derived from the reversible magnetization. This parameter is field dependent and changes at low temperatures from κ≅22 (low fields) to κ≅31 at Hc2 . The thermodynamic critical field Hc(0)=1.3kOe and the superconducting gap 2Δo/kBTc≅3.2 have been estimated. These results, together with the slightly different Hc2(T) dependence obtained for crystals and polycrystalline RbOs2O6 , evidently prove that this compound is a weak-coupling BCS-type superconductor close to the dirty limit.

  3. Two rice plasma membrane intrinsic proteins, OsPIP2;4 and OsPIP2;7, are involved in transport and providing tolerance to boron toxicity.

    PubMed

    Kumar, Kundan; Mosa, Kareem A; Chhikara, Sudesh; Musante, Craig; White, Jason C; Dhankher, Om Parkash

    2014-01-01

    Boron (B) toxicity is responsible for low cereal crop production in a number of regions worldwide. In this report, we characterized two rice genes, OsPIP2;4 and OsPIP2;7, for their involvement in B permeability and tolerance. Transcript analysis demonstrated that the expression of OsPIP2;4 and OsPIP2;7 were downregulated in shoots and strongly upregulated in rice roots by high B treatment. Expression of both OsPIP2;4 and OsPIP2;7 in yeast HD9 strain lacking Fps1, ACR3, and Ycf1 resulted in an increased B sensitivity. Furthermore, yeast HD9 strain expressing OsPIP2;4 and OsPIP2;7 accumulated significantly higher B as compared to empty vector control, which suggests their involvement in B transport. Overexpression of OsPIP2;4 and OsPIP2;7 in Arabidopsis imparted higher tolerance under B toxicity. Arabidopsis lines overexpressing OsPIP2;4 and OsPIP2;7 showed significantly higher biomass production and greater root length, however there was no difference in B accumulation in long term uptake assay. Short-term uptake assay using tracer B (¹⁰B) in shoots and roots demonstrated increased ¹⁰B accumulation in Arabidopsis lines expressing OsPIP2;4 and OsPIP2;7, compare to wild type control plants. Efflux assay of B in the roots showed that ¹⁰B was effluxed from the Arabidopsis transgenic plants overexpressing OsPIP2;4 or OsPIP2;7 during the initial 1-h of assay. These data indicate that OsPIP2;4 and OsPIP2;7 are involved in mediating B transport in rice and provide tolerance via efflux of excess B from roots and shoot tissues. These genes will be highly useful in developing B tolerant crops for enhanced yield in the areas affected by high B toxicity.

  4. OsLBD37 and OsLBD38, two class II type LBD proteins, are involved in the regulation of heading date by controlling the expression of Ehd1 in rice.

    PubMed

    Li, Chaonan; Zhu, Shanshan; Zhang, Huan; Chen, Liping; Cai, Maohong; Wang, Jiachang; Chai, Juntao; Wu, Fuqing; Cheng, Zhijun; Guo, Xiuping; Zhang, Xin; Wan, Jianmin

    2017-03-22

    LATERAL ORGAN BOUNDARIES DOMAIN (LBD) proteins are plant-specific transcription factors which are involved in many biological process of plant development, including lateral organ development, photomorphogenesis, pathogen response, pollen development and plant regeneration. Here, we report new functions of LBD proteins that participate in the regulation of heading date and yield in rice. OsLBD37 and OsLBD38 are two class II type LBD proteins, function as transcriptional activators. Overexpression of OsLBD37 and OsLBD38 separately causes delayed heading date and increased yield. Both OsLBD37 and OsLBD38 are expressed in rhythmic pattern, and their proteins are localized in the nucleus. Further analysis revealed that OsLBD37 and OsLBD38 delayed heading date by down-regulating the expression of the florigen genes Hd3a and RFT1 through key regulator of heading date Ehd1. These data indicates that OsLBD37 and OsLBD38, may function as novel regulators of heading date and crop yield in rice.

  5. Structure of the K{sup {pi}} = 4{sup +} bands in {sup 186,188}Os

    SciTech Connect

    Phillips, A. A.; Garrett, P. E.; Demand, G. A.; Finlay, P.; Green, K. L.; Leach, K. G.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Bettermann, L.; Braun, N.; Burke, D. G.; Faestermann, T.; Kruecken, R.; Wirth, H.-F.; Hertenberger, R.

    2009-01-28

    The structures of {sub 3}{sup +} states in Os have been debated over several decades. Based on measured B(E2) values they were interpreted in {sup 186-192}Os as K{sup {pi}} = 4{sup +} two-phonon vibrations, whereas inelastic scattering, and (t,{alpha}) work imply a hexadecapole phonon description. To clarify the nature of these K{sup {pi}} = 4{sup +} bands in {sup 186,188}Os, we performed a ({sup 3}He,d) reaction on {sup 185,187}Re targets using 30 MeV {sup 3}He beams and a Q3D spectrograph. Absolute cross sections were obtained for excited states up to 3 MeV at 9 angles from 5 deg. to 50 deg. Results indicate a significant (5/2){sup +}[402]{sub {pi}}+(3/2){sup +}[402]{sub {pi}} component in agreement with quasiparticle phonon model predictions for a single hexadecapole phonon structure.

  6. Q-I/IIA-OS formula for predicting left atrial pressure in mitral stenosis

    PubMed Central

    Yiğitbaşi, Ömer; Nalbantgil, İstemi; Birand, Ahmet; Terek, Ahmet

    1970-01-01

    The relation of the phonocardiographic time intervals (Q-I) and (IIA-OS) and the use of two formulas (Q-I, IIA-OS difference versus their ratio) for estimation of left atrial pressure were investigated in 70 cases of pure mitral stenosis. It was noted that, in cases with normal blood pressure and pluse rate, there was a fair correlation of the two intervals to left atrial pressure. In our studies the best correlation was obtained by using the ratio of these two intervals (Q-I)/(IIA-OS). These results indicate that it is possible to use a new formula and equation that are dependable for phonocardiographic evaluation of left atrial pressure. PMID:5433316

  7. Evolution of the X(5) critical-point symmetry in rotating {\\mathbf {^{176}Os}}

    NASA Astrophysics Data System (ADS)

    Hao, X.; Zhu, L. H.; Wu, X. G.; He, C. Y.; Pan, B.; Zheng, Y.; Wang, L. L.; Wang, L.; Li, X. Q.; Liu, Y.; Ding, H. B.; Li, Z. Y.; Zhang, J. F.; Sun, H. B.; Li, G. S.

    2011-02-01

    Lifetimes of excited states above 10+ in the yrast band in 176Os have been measured using the Doppler shift attenuation method, via the fusion evaporation reaction {^{152}Sm(^{28}Si, 4{{\\it n}})^{176}Os}. Lifetimes of states over 12+ were measured for the first time. The deduced transitional quadruple moments (Qt), together with the previous data using a recoil distance method, are compared with theoretical calculations based on the X(5) model and the interaction boson model. For the states below spin 10+, the data of previous work support an X(5)-like structure, but for the states above 10+, the value of Qt remains almost constant, being the characteristic of a symmetric rotor. The present result suggests that the shape of the nucleus 176Os changes from X(5) critical-point symmetry to an axially deformed rotor with increasing spin.

  8. The g-factor of the K = 25 isomer in /sup 182/Os

    SciTech Connect

    Alderson, A.; Broude, C.; Bruce, A.; Dafni, E.; Fallon, P.; Goldring, G.; Hass, M; Nyberg, J.; Roberts, J.; Sharpey-Schafer, J.; Sletten, G.; Twin, P.

    1988-01-01

    The g-factor of the K = I = 25, 120 ns isomer in /sup 182/Os has been measured by observing the angular precession of the decay /gamma/-rays in an external magnetic field. Our preliminary result is g = 0.46(5). Comparing this result to predictions based on experimental g-factors of single-particle Nilsson orbitals in this mass region suggests equal contributions of neutron and proton spin to the total spin of I = 25. An attempt has also been undertaken to measure the quadrupole moment of this level by observing the time-dependent quadrupole interaction pattern of Os nuclei recoiling into an Os single crystal. The analysis of the quadrupole moment measurement, as well as a more detailed analysis of the g-factor measurement, is now in progress. 7 refs., 2 figs.

  9. Treatment of os odontoideum in a patient with spastic quadriplegic cerebral palsy.

    PubMed

    Akpolat, Yusuf T; Fegale, Ben; Cheng, Wayne K

    2015-08-01

    Severe atlantoaxial instability due to os odontoideum in a patient with spastic cerebral palsy has not been well described. There is no consensus on treatment, particularly with regard to conservative or surgical options. Our patient was a 9-year-old girl with spastic cerebral palsy and unstable os odontoideum as an incidental finding. During the waiting period for elective surgical treatment, the patient developed respiratory compromise. Surgery was performed to reduce the subluxation and for C1-C2 arthrodesis and the girl regained baseline respiratory function. A CT scan was obtained 1 year after the initial surgery and revealed adequate maintenance of reduction and patency of the spinal canal. This patient highlights the fact that unstable os odontoideum can cause mortality due to respiratory distress in patients with spastic cerebral palsy. This is an important factor in deciding treatment options for cerebral palsy patients with low functional demand. We review the relevant literature.

  10. Genistein modulates the effects of parathyroid hormone in human osteoblastic SaOS-2 cells.

    PubMed

    Chen, Wen-Fang; Wong, Man-Sau

    2006-06-01

    Genistein and parathyroid hormone (PTH) are anabolic agents that stimulate bone formation through their direct actions in osteoblastic cells. In the present study, we aimed to determine whether genistein modulates the actions of PTH in human osteoblastic SaOS-2 cells in an oestrogen-depleted condition. The present results showed that genistein (10(-8) to 10(-6) m) induced alkaline phosphatase (ALP) activity and osteoprotegrin (OPG) expression in SaOS-2 cells in a dose-dependent manner. These effects could be completely abolished by co-treatment with oestrogen antagonist ICI 182780 (7alpha-[9-[(4,4,5,5,5-pentafluoropentyl)sulfonyl]nonyl]-estra-1,3,5(10)-triene-3,17beta-diol). Genistein (at 1 microM) could stimulate the mRNA expression of receptor activator of NF-kappaB ligand (RANKL). As OPG and RANKL are known to modulate osteoclastogenesis, the ability of genistein to modulate OPG and RANKL expression in SaOS-2 cells suggested that it might modulate osteoclastogenesis through its direct actions on osteoblastic cells. PTH (at 10 nM) stimulated ALP activity, induced RANKL mRNA expression and suppressed OPG mRNA expression in SaOS-2 cells, confirming its bi-directional effects on osteoblastic cells. Pre-treatment of SaOS-2 cells with genistein and oestrogen not only enhanced PTH-induced ALP activity, but also attenuated PTH up regulation of RANKL mRNA expression and PTH down regulation of OPG mRNA expression. Taken together, the present study provides the first evidence that genistein could modulate the actions of PTH in human osteoblastic SaOS-2 cells in an oestrogen-depleted condition.

  11. Redox-responsive molecular switches based on azoterpyridine-bridged Ru/Os complexes.

    PubMed

    Akasaka, Tetsuo; Otsuki, Joe; Araki, Koji

    2002-01-04

    Three new terpyridine-based dinuclear complexes, [(tpy)Ru(azotpy)Ru(tpy)]4+ (tpy = 2,2':6',2''-terpyridine, azotpy = bis[2,6-bis(2-pyridyl)-4-pyridyl]diazene), [(tpy)Os(azotpy)Os(tpy)]4+, and [(tpy)Ru(azotpy)Os(tpy)]4+ were prepared and their electrochemical and photophysical properties investigated. The bridging ligand, azotpy, in these complexes is reduced at less negative potentials than the unsubstituted tpy ligand. These complexes exhibit absorption bands due to the metal-to-ligand charge-transfer transitions both to the unsubstituted tpy ligand and the bridging azotpy ligand, the latter absorption being observed at the lower energy side of the former. These observations are consistent with the lower lying pi* level of the azotpy ligand than that of the tpy ligand. These complexes are nonluminescent, since the excited electron is trapped in this lower lying pi* level of the azotpy ligand in the excited state. Reduction of this bridging ligand by constant potential electrolysis renders the shape of absorption spectra for these complexes nearly identical to those of the parent complexes, [M(tpy)2]2+ (M = Ru, Os). In this reduced state, the homodinuclear Os complex becomes luminescent at room temperature, whereas the homodinuclear Ru complex becomes luminescent at 77 K, thus establishing their photoswitching behavior. The reduced heterodinuclear complex exhibits luminescence from the Os center, which is sensitized by the Ru center in the same molecule as evidenced by the excitation spectra. Thus, the intramolecular energy transfer can be switched on and off by the redox reaction of the bridging component.

  12. Overexpression of the OsERF71 Transcription Factor Alters Rice Root Structure and Drought Resistance.

    PubMed

    Lee, Dong-Keun; Jung, Harin; Jang, Geupil; Jeong, Jin Seo; Kim, Youn Shic; Ha, Sun-Hwa; Do Choi, Yang; Kim, Ju-Kon

    2016-09-01

    Plant responses to drought stress require the regulation of transcriptional networks via drought-responsive transcription factors, which mediate a range of morphological and physiological changes. AP2/ERF transcription factors are known to act as key regulators of drought resistance transcriptional networks; however, little is known about the associated molecular mechanisms that give rise to specific morphological and physiological adaptations. In this study, we functionally characterized the rice (Oryza sativa) drought-responsive AP2/ERF transcription factor OsERF71, which is expressed predominantly in the root meristem, pericycle, and endodermis. Overexpression of OsERF71, either throughout the entire plant or specifically in roots, resulted in a drought resistance phenotype at the vegetative growth stage, indicating that overexpression in roots was sufficient to confer drought resistance. The root-specific overexpression was more effective in conferring drought resistance at the reproductive stage, such that grain yield was increased by 23% to 42% over wild-type plants or whole-body overexpressing transgenic lines under drought conditions. OsERF71 overexpression in roots elevated the expression levels of genes related to cell wall loosening and lignin biosynthetic genes, which correlated with changes in root structure, the formation of enlarged aerenchyma, and high lignification levels. Furthermore, OsERF71 was found to directly bind to the promoter of OsCINNAMOYL-COENZYME A REDUCTASE1, a key gene in lignin biosynthesis. These results indicate that the OsERF71-mediated drought resistance pathway recruits factors involved in cell wall modification to enable root morphological adaptations, thereby providing a mechanism for enhancing drought resistance.

  13. High pressure structural phase transition of osmium nitride (OsN)

    NASA Astrophysics Data System (ADS)

    Sarwan, Madhu; Abdul Shukoor, V.; Dubey, Ritu; Singh, Sadhna

    2015-05-01

    The structural phase transition and relative volume change of OsN compound has been investigated by means of interaction potential model (IPM) which consists of Coulomb interaction, three-body interaction (TBI), van der Waal interaction (vdW) and short range overlap repulsive interactions up to second neighbor ions. It is found that the OsN transforms from zinc-blende structure (B3) to rock-salt structure (B1) at 87.0 GPa. The second order elastic constants are also investigated. These results are compared with available results.

  14. Painful Os Peroneum Syndrome: Underdiagnosed Condition in the Lateral Midfoot Pain

    PubMed Central

    de Souza, Barbara Nogueira Caracas

    2016-01-01

    Os peroneum is an accessory ossicle located within the peroneus longus tendon. The painful os peroneum syndrome (POPS) results from a wide spectrum of conditions, including fractures, diastases, and other causes. POPS can result in tenosynovitis or discontinuity of the peroneus longus tendon with a clinical presentation of pain in the lateral aspect of the midfoot. Authors report a typical case of POPS, illustrating this entity through different imaging methods (radiographs, ultrasound, and magnetic resonance imaging). We emphasize the prevalence of this ossicle and discuss painful complications. PMID:27478674

  15. New supersymmetric quartet of nuclei: {sup 192,193}Os-{sup 193,194}Ir

    SciTech Connect

    Bijker, R.; Frank, A.; Barea, J.; Graw, G.; Wirth, H.-F.; Hertenberger, R.; Jolie, J.

    2009-01-28

    We present evidence for the existence of a new supersymmetric quartet of nuclei in the A{approx}190 mass region. The analysis is based on new experimental information on the odd-odd nucleus {sup 194}Ir from transfer and neutron capture reactions. The new data allow the identification of a new supersymmetric quartet, consisting of the {sup 192,193}Os and {sup 193,194}Ir nuclei. We make explicit predictions for {sup 193}Os, and suggest that its spectroscopic properties be measured in dedicated experiments. Finally, we study correlations between different transfer reactions.

  16. 187Re - 187Os nuclear geochronometry: age dating with permil precision

    NASA Astrophysics Data System (ADS)

    Roller, Goetz

    2016-04-01

    Recently, 187Re - 187Os nuclear geochronometry, a new dating method combining ideas of nuclear astrophysics with geochronology, has successfully been used to calculate two-point-isochron (TPI) ages for Devonian black gas shales using the isotopic signature of an r-process geochronometer as one data point in a TPI diagram [1]. Based upon a nuclear production ratio 187Re/188Os = 5.873, TPI ages were calculated for 12 SDO-1 (Devonian Ohio Shale, Appalachian Basin) aliquants, for which repeated Re-Os measurements are reported in the literature [2]. TPI ages range from 384.5 ± 2.7 Ma (187Os/188Osi = 0.29413 ± 0.00023) to 387.7 ± 2.1 Ma (187Os/188Osi = 0.29407 ± 0.00019) with a mean of 386.67 ± 1.79 Ma). The result is consistent with the isochronous age from the 12 aliquants alone (386 ± 16 Ma, 187Os/188Osi = 0.31±0.31), which is bracketed by U-Pb ages for the Belpre Ash (381.1 ± 3.3 Ma) and the Tioga Ash bed (390.0 ± 2.5 Ma) [3] from the Appalachian Basin. Hence, SDO-1 can be assigned to the Givetian stage (varcus-zone) of the Middle Devonian, close to the Eifelian/Givetian boundary (using the time-scale of [3] or [4]). If an age is calculated from an isochron diagram for the 12 aliquants including the nuclear geochronometer, a permil precision can be achieved, an interesting feature with respect to any effort towards calibrating the Geologic Timescale. Additionally, a Th/U evolution (or: Th/U-time) diagram can be plotted using U-Pb zircon age data and Th/U ratios from volcanic rocks and ashes reported in the literature [3] for specific Devonian samples from the Appalachian Basin. Since the Re-Os age obtained for SDO-1 can also be connected to its Th/U ratio, it turns out, that Th/U ratios might be helpful age indicators, as demonstrated for the Devonian using the U-Pb and Re-Os datasets. [1] Roller (2015), GSA Abstr. with Programs 47, #248-14. [2] Du Vivier et al. (2014), Earth Planet. Sci. Lett. 389, 23 - 33. [3] Tucker et al. (1998), Earth Planet. Sci. Lett

  17. Strongly gapped spin-wave excitation in the insulating phase of NaOsO3

    NASA Astrophysics Data System (ADS)

    Calder, S.; Vale, J. G.; Bogdanov, N.; Donnerer, C.; Pincini, D.; Moretti Sala, M.; Liu, X.; Upton, M. H.; Casa, D.; Shi, Y. G.; Tsujimoto, Y.; Yamaura, K.; Hill, J. P.; van den Brink, J.; McMorrow, D. F.; Christianson, A. D.

    2017-01-01

    NaOsO3 hosts a rare manifestation of a metal-insulator transition driven by magnetic correlations, placing the magnetic exchange interactions in a central role. We use resonant inelastic x-ray scattering to directly probe these magnetic exchange interactions. A dispersive and strongly gapped (58 meV) excitation is observed, indicating appreciable spin-orbit coupling in this 5 d3 system. The excitation is well described within a minimal model Hamiltonian with strong anisotropy and Heisenberg exchange (J1=J2=13.9 meV ). The observed behavior places NaOsO3 on the boundary between localized and itinerant magnetism.

  18. Re-Os isotopic systematics of primitive lavas from the Lassen region of the Cascade arc, California

    USGS Publications Warehouse

    Borg, L.E.; Brandon, A.D.; Clynne, M.A.; Walker, R.J.

    2000-01-01

    Rhenium-osmium isotopic systematics of primitive calc-alkaline lavas from the Lassen region appear to be controlled by mantle wedge processes. Lavas with a large proportion of slab component have relatively low Re and Os abundances, and have radiogenic Os and mid ocean ridge basalt-like Sr and Pb isotopic compositions. Lavas with a small proportion of slab component have higher Re and Os elemental abundances and display mantle-like Os, Sr, Nd, and Pb isotopic compositions. Assimilation with fractional crystallization can only generate the Re-Os systematics of the Lassen lavas from a common parent if the distribution coefficient for Re in sulfide is ~40-1100 times higher than most published estimates and if most incompatible element abundances decrease during differentiation. High Re/Os ratios in mid ocean ridge basalts makes subducted oceanic crust a potential source of radiogenic Os in volcanic arcs. The slab beneath the southernmost Cascades is estimated to have 187Os/188Os ratios as high as 1.4. Mixing between a slab component and mantle wedge peridotite can generate the Os isotopic systematics of the Lassen lavas provided the slab component has a Sr/Os ratio of ~7.5X105 and Os abundances that are 100-600 times higher than mid ocean ridge basalts. For this model to be correct, Os must be readily mobilized and concentrated in the slab component, perhaps as a result of high water and HCl fugacities in this subduction environment. Another possible mechanism to account for the correlation between the magnitude of the subduction geochemical signature and Os isotopic composition involves increasing the stability of an Os-bearing phase in mantle wedge peridotites as a result of fluxing with the slab component. Melting of such a source could yield low Os magmas that are more susceptible to crustal contamination, and hence have more radiogenic Os isotopic compositions, than magmas derived from sources with a smaller contribution from the slab. Thus, the addition of the

  19. OsSRT1 is involved in rice seed development through regulation of starch metabolism gene expression.

    PubMed

    Zhang, Hua; Lu, Yue; Zhao, Yu; Zhou, Dao-Xiu

    2016-07-01

    OsSRT1 is a NAD(+)-dependent histone deacetylase, closely related to the human SIRT6 that plays key roles in genome stability and metabolic homeostasis. In this work, we investigated the role of OsSRT1 in rice seed development. Down-regulation of OsSRT1 induced higher expression of Rice Starch Regulator1 (RSR1) and amylases genes in developing seeds, which resulted in a decrease of starch synthesis and an increase of starch degradation, leading to abnormal seed development. ChIP assay showed that OsSRT1 was required to reduce histone H3K9 acetylation on starch metabolism genes and transposons in developing seeds. In addition, OsSRT1 was detected to directly bind to starch metabolism genes such as OsAmy3B, OsAmy3E, OsBmy4, and OsBmy9. Our results suggested that OsSRT1-mediated histone deacetylation is involved in starch accumulation and transposon repression to regulate normal seed development.

  20. G-protein Stimulatory α Subunit Is Involved in Osteogenic Activity in Osteoblastic Cell Line SaOS-2 Cells.

    PubMed

    Yamazaki, Miwa; Suzuki, Akira; Ozono, Keiichi; Michigami, Toshimi

    2006-01-01

    In an attempt to study the roles of G-protein stimulatory subunit α (Gsα) in osteoblasts, we introduced an expression vector encoding Gsα into human osteoblastic cell line SaOS-2, and established the clones stably overexpressing Gsα (SaOS-2-Gsα). In SaOS-2-Gsα, the intracellular content of cyclic AMP (cAMP) was increased compared with the parental SaOS-2 cells. In addition, when treated with PTH[1-34], SaOS-2-Gsα exhibited more accumulation of intracellular cAMP compared with the parental cells, suggesting an increased responsiveness to PTH. We evaluated the proliferation rates of SaOS-2-Gsα and the parental SaOS-2 cells, and found that the proliferation was accelerated in SaOS-2-Gsα cells. Reverse transcription-polymerase chain reaction (RT-PCR) analyses exhibited the increased expression of Runx2, a transcription factor involved in osteoblast differentiation, in SaOS-2-Gsα cells. Finally, to examine the osteoblastic function in vivo, we inoculated SaOS-2-Gsα or parental SaOS-2 cells subcutaneously to immunocompromised nude mice. Although tumors in nude mice were not formed after inoculation of parental SaOS-2 cells, SaOS-2-Gsα cells proliferated in host animals leading to the formation of tumors with mineralized bone-like tissues. Taken together, these results suggest that the signals via Gsα play critical roles in the proliferation and osteogenic functions of osteoblasts.

  1. A detrital model for the origin of gold and sulfides in the Witwatersrand basin based on Re-Os isotopes

    NASA Astrophysics Data System (ADS)

    Kirk, Jason; Ruiz, Joaquin; Chesley, John; Titley, Spencer; Walshe, John

    2001-07-01

    The Re-Os systematics of gold and sulfides from the Witwatersrand basin were utilized to determine whether the gold is detrital or was introduced by hydrothermal solutions from outside the basin. Gold from a gravity concentrate from the Western Areas Gold Plant and gold from the Vaal Reef have very high Os concentrations of approximately 73 to 10000 ppb and 3 to 32 ppb Re, resulting in 187Re/ 188Os ratios of 0.010 to 0.185. The gold has subchondritic 187Os/ 188Os ratios between 0.1056 to 0.1099 and an average value of 0.1067. Rhenium depletion ages (T RD) range from 3.5 Ga to 2.9 Ga, with a median age of 3.3 Ga. Pyrite from the Vaal Reef have Os concentrations ranging from 0.26 to 0.68 ppb, Re concentrations of 1.7 to 2.8 ppb and 187Re/ 188Os ratios of approximately 14 to 87. The pyrite samples have measured 187Os/ 188Os ratios of 0.84 to 4.7 and define an isochron with an age of 2.99 ± 0.11 Ga (MSWD = 0.77). The Os isotopic data from the direct measurement of gold preclude introduction of gold to the Witwatersrand basin from crustally derived metamorphic or hydrothermal fluids between 2.7 to 2.0 Ga. The unradiogenic 187Os/ 188Os ratios, old T RD ages of the Western Areas and Vaal Reef gold samples, as well as the contemporaneously old age of the Vaal Reef pyrite are consistent with detrital deposition of gold during the formation of the Witswatersrand basin. The Os data will allow for minor hydrothermal remobilization and/or overprinting of hydrothermal gold on preexisting detrital gold grains but does not support the introduction of gold solely by hydrothermal fluids.

  2. Unravelling the effects of melt depletion and secondary infiltration on mantle Re-Os isotopes beneath the French Massif Central

    NASA Astrophysics Data System (ADS)

    Harvey, J.; Gannoun, A.; Burton, K. W.; Schiano, P.; Rogers, N. W.; Alard, O.

    2010-01-01

    Spinel lherzolite xenoliths from Mont Briançon, French Massif Central, retain evidence for multiple episodes of melt depletion and melt/fluid infiltration (metasomatism). Evidence for primary melt depletion is still preserved in the co-variation of bulk-rock major elements (MgO 38.7-46.1 wt.%; CaO 0.9-3.6 wt.%), and many samples yield unradiogenic bulk-rock Os isotope ratios ( 187Os/ 188Os = 0.11541-0.12626). However, many individual xenoliths contain interstitial glasses and melt inclusions that are not in equilibrium with the major primary minerals. Incompatible trace element mass balance calculations demonstrate that metasomatic components comprise a significant proportion of the bulk-rock budget for these elements in some rocks, ranging to as much as 25% of Nd and 40% of Sr Critically, for Re-Os geochronology, melt/fluid infiltration is accompanied by the mobilisation of sulfide. Consequently, bulk-rock isotope measurements, whether using lithophile (e.g. Rb-Sr, Sm-Nd) or siderophile (Re-Os) based isotope systems, may only yield a perturbed and/or homogenised average of these multiple events. Osmium mass balance calculations demonstrate that bulk-rock Os in peridotite is dominated by contributions from two populations of sulfide grain: (i) interstitial, metasomatic sulfide with low [Os] and radiogenic 187Os/ 188Os, and (ii) primary sulfides with high [Os] and unradiogenic 187Os/ 188Os, which have been preserved within host silicate grains and shielded from interaction with transient melts and fluid. The latter can account for >97% of bulk-rock Os and preserve geochronological information of the melt from which they originally precipitated as an immiscible liquid. The Re-depletion model ages of individual primary sulfide grains preserve evidence for melt depletion beneath the Massif Central from at least 1.8 Gyr ago despite the more recent metasomatic event(s).

  3. Re-Os Isotopic Constraints on the Chemical Evolution and Differentiation of the Martian Mantle

    NASA Technical Reports Server (NTRS)

    Brandon, Alan D.; Walker, Richard J.

    2002-01-01

    The (187)Re-187Os isotopic systematics of SNC meteorites, thought to be from Mars, provide valuable information regarding the chemical processes that affected the Martian mantle, particularly with regard to the relative abundances of highly siderophile elements (HSE). Previously published data (Birck and Allegre 1994, Brandon et al. 2000), and new data obtained since these studies, indicate that the HSE and Os isotopic composition of the Martian mantle was primarily set in its earliest differentiation history. If so, then these meteorites provide key constraints on the processes that lead to variation in HSE observed in not only Mars, but also Earth, the Moon and other rocky bodies in the Solar System. Processes that likely have an effect on the HSE budgets of terrestrial mantles include core formation, magma ocean crystallization, development of juvenile crust, and the addition of a late veneer. Each of these processes will result in different HSE variation and the isotopic composition of mantle materials and mantle derived lavas. Two observations on the SNC data to present provide a framework for which to test the importance of each of these processes. First, the concentrations of Re and Os in SNC meteorites indicate that they are derived from a mantle that has similar concentrations to the Earth's mantle. Such an observation is consistent with a model where a chondritic late veneer replenished the Earth and Martian mantles subsequent to core formation on each planet. Alternative models to explain this observation do exist, but will require additional data to test the limitations of each. Second, Re-Os isotopic results from Brandon et al. (2000) and new data presented here, show that initial yos correlates with variations in the short-lived systems of (182)Hf- (182)W and (142)Sm-142Nd in the SNC meteorites (epsilon(sub W) and epsilon(sub 142Nd)). These systematics require an isolation of mantle reservoirs during the earliest differentiation history of Mars, and

  4. Effects of chemical pressure on the magnetic ground states of the osmate double perovskites SrCaCoOs6 and Ca2CoOsO6

    SciTech Connect

    Morrow, Ryan; Yan, Jiaqiang; McGuire, Michael A.; Freeland, John W.; Haskel, Daniel; Woodward, Patrick M.

    2015-09-21

    The magnetic ground state in the double perovskite system Sr2-xCaxCoOsO6 changes from an antiferromagnet (x=0), to a spin glass (x=1), to a ferrimagnet (x=2) as the Ca content increases. Moreover, this crossover is driven by chemical pressure effects that control the relative strength of magnetic exchange interactions. The synthesis, crystal structure, and magnetism of SrCaCoOsO6 and Ca2CoOsO6 are investigated and compared with Sr2CoOsO6. Both compounds adopt a monoclinic crystal structure with rock-salt ordering of Co2+ and Os6+ and a-a-b+ octahedral tilting, but the average Co–O–Os bond angle evolves from 158.0(3) in SrCaCoOsO6 to 150.54(9)° in Ca2CoOsO6 as the smaller Ca2+ ion replaces Sr2+. And while this change may seem minor, it has a profound effect on the magnetism, changing the magnetic ground state from antiferromagnetic in Sr2CoOsO6 (TN1=108K, TN2=70K), to a spin glass in SrCaCoOsO6 (Tf1=32K, Tf2=13K), to ferrimagnetic in Ca2CoOsO6 (TC=145K). Finally, in the first two compounds the observation of two transitions is consistent with weak coupling between the Co and Os sublattices.

  5. Especially Social: Exploring the Use of an iOS Application in Special Needs Classrooms

    ERIC Educational Resources Information Center

    Campigotto, Rachelle; McEwen, Rhonda; Epp, Carrie Demmans

    2013-01-01

    A five-month exploratory study was conducted with iOS mobile devices in two Toronto area schools with students in grades 7 through 12. Both classrooms were identified as Special Education classes by the Ontario Ministry of Education, and each student was identified as having exceptionalities requiring additional support and differentiation within…

  6. Quantum mechanical effects in tilted axis rotation in {sup 182}Os

    SciTech Connect

    Hashimoto, Yukio; Horibata, Takatoshi

    2010-05-12

    We performed the three-dimensional cranked Hartree-Fock-Bogoliubov calculation for {sup 182}Os. A family of states obtained by the calculation are expected to be the t-band with K = 8. We suggest a quantum mechanical mechanism which is responsible for the occurrence of a signature splitting in the t-band.

  7. Lifetimes of the first excited 2{sup +} states in {sup 176,178,180}Os

    SciTech Connect

    Moeller, O.; Melon, B.; Dewald, A.; Fitzler, A.; Jolie, J.; Christen, S.; Saha, B.; Zell, K.O.; Heidemann, M.; Petkov, P.; Tonev, D.

    2005-09-01

    By use of the pulsed-beam technique, the lifetimes of the first excited 2{sup +} states in {sup 176,178}Os were measured for the first time and the lifetime of the 2{sub 1}{sup +} state in {sup 180}Os was determined to a greater accuracy. In addition, for {sup 178}Os, a recoil-distance Doppler-shift experiment and an experiment to measure the nuclear deorientation effect that is due to the hyperfine interactions were also performed. The results obtained from this measurement are consistent with the lifetime value extracted by means of the pulsed-beam experiment. As well, the lifetimes of two I{sup {pi}}=7{sup -} isomers in {sup 180}Os were determined more accurately. Together with previously published data for the even-even osmium isotopes, the newly determined B(E2,2{sub 1}{sup +}{yields}0{sub 1}{sup +}) transition strengths show a maximum value at the N=104 midshell. This maximum corresponds to the simple expectation of the N{sub {pi}}N{sub {nu}} rule of the interacting boson approximation (IBA) but remains to be explained by microscopic models.

  8. Hexagonal OsB2: Sintering, microstructure and mechanical properties

    SciTech Connect

    Xie, Zhilin; Lugovy, Mykola; Orlovskaya, Nina; Graule, Thomas; Kuebler, Jakob; Mueller, Martin; Gao, Huili; Radovic, Miladin; Cullen, David A.

    2015-02-07

    In this study, the metastable high pressure ReB2-type hexagonal OsB2 bulk ceramics was produced by spark plasma sintering. The phase composition, microstructure, and mechanical behavior of the sintered OsB2 were studied by X-ray diffraction, optical microscopy, TEM, SEM, EDS, and nanoindentation. The produced ceramics was rather porous and contained a mixture of hexagonal (~80 wt.%) and orthorhombic (~20 wt.%) phases as identified by X-ray diffraction and EBSD analysis. Two boron-rich phases, which do not contain Os, were also identified by TEM and SEM/EDS analysis. Nanoindentation measurements yielded a hardness of 31 ± 9 GPa and Young’s modulus of 574 ± 112 GPa, indicating that the material is rather hard and very stiff; but, it is very prone to crack formation and propagation, which is indicative of a very brittle nature of this material. Improvements in the sintering regime are required in order to produce dense, homogeneous and single phase hexagonal OsB2 bulk ceramics.

  9. Anisotropic type-I superconductivity and anomalous superfluid density in OsB2

    NASA Astrophysics Data System (ADS)

    Bekaert, J.; Vercauteren, S.; Aperis, A.; Komendová, L.; Prozorov, R.; Partoens, B.; Milošević, M. V.

    2016-10-01

    We present a microscopic study of superconductivity in OsB2, and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ —a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, our calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity.

  10. Positioning and Latinas/os: A Study of Small-Group Interactions in Mathematics

    ERIC Educational Resources Information Center

    Lopez Leiva, Carlos Alfonso

    2011-01-01

    This study explores social interaction and mathematics performance, especially regarding how bilingual Latino/a students' positioning and participation evolved as they interacted with others in mathematics problem solving. Historically, Latinas/os have faced segregation in different ways that affect the quality of their social interactions…

  11. Overexpression of a Chimeric Gene, OsDST-SRDX, Improved Salt Tolerance of Perennial Ryegrass

    PubMed Central

    Cen, Huifang; Ye, Wenxing; Liu, Yanrong; Li, Dayong; Wang, Kexin; Zhang, Wanjun

    2016-01-01

    The Drought and Salt Tolerance gene (DST) encodes a C2H2 zinc finger transcription factor, which negatively regulates salt tolerance in rice (Oryza sativa). Phylogenetic analysis of six homologues of DST genes in different plant species revealed that DST genes were conserved evolutionarily. Here, the rice DST gene was linked to an SRDX domain for gene expression repression based on the Chimeric REpressor gene-Silencing Technology (CRES-T) to make a chimeric gene (OsDST-SRDX) construct and introduced into perennial ryegrass by Agrobacterium-mediated transformation. Integration and expression of the OsDST-SRDX in transgenic plants were tested by PCR and RT-PCR, respectively. Transgenic lines overexpressing the OsDST-SRDX fusion gene showed obvious phenotypic differences and clear resistance to salt-shock and to continuous salt stresses compared to non-transgenic plants. Physiological analyses including relative leaf water content, electrolyte leakage, proline content, malondialdehyde (MDA) content, H2O2 content and sodium and potassium accumulation indicated that the OsDST-SRDX fusion gene enhanced salt tolerance in transgenic perennial ryegrass by altering a wide range of physiological responses. To our best knowledge this study is the first report of utilizing Chimeric Repressor gene-Silencing Technology (CRES-T) in turfgrass and forage species for salt-tolerance improvement. PMID:27251327

  12. Public Discourse versus Public Policy: Latinas/os, Affirmative Action, and the Court of Public Opinion

    ERIC Educational Resources Information Center

    Ledesma, María C.

    2015-01-01

    The purpose of this article is to highlight the power of popular discourse in shaping public policy debates concerning educational access and opportunity for historically marginalized and minoritized students, especially for Latinas/os. I argue that proponents of race-conscious policies would do well to challenge the elimination of affirmative…

  13. Examining Education for Latinas/os in Chicago: A CRT/LatCrit Approach

    ERIC Educational Resources Information Center

    Davila, Erica R.; de Bradley, Ann Aviles

    2010-01-01

    This article explores the sociopolitical context of education policy, particularly as it relates to Latina/o education. The authors highlight the status of Latinas/os within the Chicago Public Schools (CPS) to examine the impact of education policy designed to benefit few and disenfranchise most. They draw attention to the injustices of Latinas/os…

  14. Rice putative methyltransferase gene OsTSD2 is required for root development involving pectin modification

    PubMed Central

    Qu, Lianghuan; Wu, Chunyan; Zhang, Fei; Wu, Yangyang; Fang, Chuanying; Jin, Cheng; Liu, Xianqing; Luo, Jie

    2016-01-01

    Pectin synthesis and modification are vital for plant development, although the underlying mechanisms are still not well understood. Here, we report the functional characterization of the OsTSD2 gene, which encodes a putative methyltransferase in rice. All three independent T-DNA insertion lines of OsTSD2 displayed dwarf phenotypes and serial alterations in different zones of the root. These alterations included abnormal cellular adhesion and schizogenous aerenchyma formation in the meristematic zone, inhibited root elongation in the elongation zone, and higher lateral root density in the mature zone. Immunofluorescence (with LM19) and Ruthenium Red staining of the roots showed that unesterified homogalacturonan (HG) was increased in Ostsd2 mutants. Biochemical analysis of cell wall pectin polysaccharides revealed that both the monosaccharide composition and the uronic acid content were decreased in Ostsd2 mutants. Increased endogenous ABA content and opposite roles performed by ABA and IAA in regulating cellular adhesion in the Ostsd2 mutants suggested that OsTSD2 is required for root development in rice through a pathway involving pectin synthesis/modification. A hypothesis to explain the relationship among OsTSD2, pectin methylesterification, and root development is proposed, based on pectin’s function in regional cell extension/division in a zone-dependent manner. PMID:27497286

  15. Posterior Endoscopic Excision of Os Trigonum in Professional National Ballet Dancers.

    PubMed

    Ballal, Moez S; Roche, Andy; Brodrick, Anna; Williams, R Lloyd; Calder, James D F

    2016-01-01

    Previous studies have compared the outcomes after open and endoscopic excision of an os trigonum in patients of mixed professions. No studies have compared the differences in outcomes between the 2 procedures in elite ballet dancers. From October 2005 to February 2010, 35 professional ballet dancers underwent excision of a symptomatic os trigonum of the ankle after a failed period of nonoperative treatment. Of the 35 patients, 13 (37.1%) underwent endoscopic excision and 22 (62.9%) open excision. We compared the outcomes, complications, and time to return to dancing. The open excision group experienced a significantly greater incidence of flexor hallucis longus tendon decompression compared with the endoscopic group. The endoscopic release group returned to full dance earlier at a mean of 9.8 (range 6.5 to 16.1) weeks and those undergoing open excision returned to full dance at a mean of 14.9 (range 9 to 20) weeks (p = .001). No major complications developed in either group, such as deep infection or nerve or vessel injury. We have concluded that both techniques are safe and effective in the treatment of symptomatic os trigonum in professional ballet dancers. Endoscopic excision of the os trigonum offers a more rapid return to full dance compared with open excision.

  16. OS3D/GIMRT software for modeling multicomponent-multidimensional reactive transport

    SciTech Connect

    CI Steefel; SB Yabusaki

    2000-05-17

    OS3D/GIMRT is a numerical software package for simulating multicomponent reactive transport in porous media. The package consists of two principal components: (1) the code OS3D (Operator Splitting 3-Dimensional Reactive Transport) which simulates reactive transport by either splitting the reaction and transport steps in time, i.e., the classic time or operator splitting approach, or by iterating sequentially between reactions and transport, and (2) the code GIMRT (Global Implicit Multicomponent Reactive Transport) which treats up to two dimensional reactive transport with a one step or global implicit approach. Although the two codes do not yet have totally identical capabilities, they can be run from the same input file, allowing comparisons to be made between the two approaches in many cases. The advantages and disadvantages of the two approaches are discussed more fully below, but in general OS3D is designed for simulation of transient concentration fronts, particularly under high Peclet number transport conditions, because of its use of a total variation diminishing or TVD transport algorithm. GIMRT is suited for simulating water-rock alteration over long periods of time where the aqueous concentration field is at or close to a quasi-stationary state and the numerical transport errors are less important. Where water-rock interaction occurs over geological periods of time, GIMRT may be preferable to OS3D because of its ability to take larger time steps.

  17. Latinas/os in Community College Developmental Education: Increasing Moments of Academic and Interpersonal Validation

    ERIC Educational Resources Information Center

    Acevedo-Gil, Nancy; Santos, Ryan E.; Alonso, LLuliana; Solorzano, Daniel G.

    2015-01-01

    This qualitative study examines the experiences of Latinas/os in community college English and math developmental education courses. Critical race theory in education and the theory of validation serve as guiding frameworks. The authors find that institutional agents provide academic validation by emphasizing high expectations, focusing on social…

  18. Anisotropic type-I superconductivity and anomalous superfluid density in OsB2

    DOE PAGES

    Bekaert, Jonas; Vercauteren, S.; Aperis, A.; ...

    2016-10-12

    Here, we present a microscopic study of superconductivity in OsB2, and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ—a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, ourmore » calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity.« less

  19. Thermodynamics and superconductivity of Th7(Fe, Ru, Os, Co, Rh, Ir)3 system

    SciTech Connect

    Smith, James L; Lashley, Jason C; Volz, Heather M; Fisher, Robert A

    2008-01-01

    Expanding the temperature range of previous specific-heat measurements on the Th7(Fe, Ru, Os, Co, Rh, Ir)3 system, we measure the effect of transition-metal substitution on total entropy (S{sub 298 k}), electronic specific heat ({gamma}), and Debye temperature ({Theta}D). In addition we measure the pressure dependence, up to 10 kbar, of the superconducting transition.

  20. Latina/os Leaving Legacies: The Experiences of California Community College Leaders

    ERIC Educational Resources Information Center

    Lopez, Vinicio Jesus

    2013-01-01

    The purpose of this qualitative study was to develop a comprehensive understanding of Latina/o leadership in community colleges through in-depth interviews of current community college executive administrators. The portraits of the subjects offer a blueprint to Latina/os who have similar career aspirations; and more succinctly, provide insight…

  1. The rice OsLpa1 gene encodse a novel protein involved in phytic acid metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rice low phytic acid 1 (OsLpa1) gene was originally identified using a forward genetics approach. Mutation of this gene resulted in a 45% reduction in rice seed phytic acid with a molar-equivalent increase in inorganic phosphorus; however, the rice lpa1 mutant does not appear to differ significa...

  2. The contribution of O.S. Vialov to the development of ichnological classification and nomenclature

    NASA Astrophysics Data System (ADS)

    Palii, V. M.

    2013-05-01

    This work highlights the role of O.S. Vialov, an outstanding Soviet geologist and paleontologist, and Academician of the Academy of Sciences of the Ukrainian SSR, in the creation and development of classification and nomenclature of fossil traces left by organisms.

  3. Lithium dendrite and solid electrolyte interphase investigation using OsO4

    NASA Astrophysics Data System (ADS)

    Zier, Martin; Scheiba, Frieder; Oswald, Steffen; Thomas, Jürgen; Goers, Dietrich; Scherer, Torsten; Klose, Markus; Ehrenberg, Helmut; Eckert, Jürgen

    2014-11-01

    Osmium tetroxide (OsO4) staining, commonly used to enhance scattering contrast in electron microscopy of biologic tissue and polymer blends, has been adopted for studies of graphite anodes in lithium-ion batteries. OsO4 shows a coordinated reaction with components of the solid electrolyte interphase (SEI) and lithium dendrites, thereby increasing material contrast for scanning electron microscopy investigations. Utilizing the high affinity of lithium metal to react with osmium tetroxide it was possible to localize even small lithium deposits on graphite electrodes. In spite of their reaction with the OsO4 fume, the lithium dendrite morphology remains almost untouched by the staining procedure, offering information on the dendrite growth process. Correlating the quantity of osmium detected with the amount of residual ("dead") lithium of a discharged electrode, it was possible to obtain a practical measure for lithium plating and stripping efficiencies. EDX mappings allowed for a localization of electrochemically stripped lithium dendrites by their residual stained SEI shells. Cross sections, prepared by focused ion beam (FIB) of cycled graphite electrodes treated with OsO4, revealed important information about deposition and distribution of metallic lithium and the electrolyte reduction layer across the electrode.

  4. Re-Os, Rb-Sr, and O isotopic systematics of the Archean Kolar schist belt, Karnataka, India

    NASA Technical Reports Server (NTRS)

    Walker, Richard J.; Shirey, Steven B.; Hanson, Gilbert N.; Rajamani, V.; Horan, Mary F.

    1989-01-01

    The Re-Os, Rb-Sr, and O isotopic compositions of mafic and ultramafic amphibolites, gold ores, and granitic gneisses of the circa 2700 Ma Kolar schist belt are reported which reveal at least two episodes of postmagmatic alteration that affected these systems. The Re-Os isotopic systematics of many of the belt rocks indicate that Os was introduced to the area via fluids that carried very radiogenic Os, probably from ancient crust. The Rb-Sr systematics of most of these rocks indicate that the alteration event probably occurred no later than the early Proterozoic. Samples of several komatiitic amphibolites have very Os-187-depleted compositions, indicating that open-system behavior also occurred at a much later time than the late Archean or early Proterozoic. The results suggest that the Re-Os system may have only limited utility for geochronologic applications in regions for which postcrystallization noble metal mineralization is evident.

  5. OsMYC2, an essential factor for JA-inductive sakuranetin production in rice, interacts with MYC2-like proteins that enhance its transactivation ability

    PubMed Central

    Ogawa, Satoshi; Miyamoto, Koji; Nemoto, Keiichirou; Sawasaki, Tatsuya; Yamane, Hisakazu; Nojiri, Hideaki; Okada, Kazunori

    2017-01-01

    Biosynthesis of sakuranetin, a flavonoid anti-fungal phytoalexin that occurs in rice, is highly dependent on jasmonic acid (JA) signalling and induced by a variety of environmental stimuli. We previously identified OsNOMT, which encodes naringenin 7-O-methyltransferase (NOMT); NOMT is a key enzyme for sakuranetin production. Although OsNOMT expression is induced by JA treatment, the regulation mechanism that activates the biosynthetic pathway of sakuranetin has not yet been elucidated. In this study, we show that JA-inducible basic helix-loop-helix transcriptional factor OsMYC2 drastically enhances the activity of the OsNOMT promoter and is essential for JA-inducible sakuranetin production. In addition, we identified 2 collaborators of OsMYC2, OsMYC2-like protein 1 and 2 (OsMYL1 and OsMYL2) that further activated the OsNOMT promoter in synergy with OsMYC2. Physical interaction of OsMYC2 with OsMYL1 and OsMYL2 further supported the idea that these interactions lead to the enhancement of the transactivation activity of OsMYC2. Our results indicate that JA signalling via OsMYC2 is reinforced by OsMYL1 and OsMYL2, resulting in the inductive production of sakuranetin during defence responses in rice. PMID:28067270

  6. The Crystal Structure of the Plant Small GTPase OsRac1 Reveals Its Mode of Binding to NADPH Oxidase*

    PubMed Central

    Kosami, Ken-ichi; Ohki, Izuru; Nagano, Minoru; Furuita, Kyoko; Sugiki, Toshihiko; Kawano, Yoji; Kawasaki, Tsutomu; Fujiwara, Toshimichi; Nakagawa, Atsushi; Shimamoto, Ko; Kojima, Chojiro

    2014-01-01

    Rac/Rop proteins are Rho-type small GTPases that act as molecular switches in plants. Recent studies have identified these proteins as key components in many major plant signaling pathways, such as innate immunity, pollen tube growth, and root hair formation. In rice, the Rac/Rop protein OsRac1 plays an important role in regulating the production of reactive oxygen species (ROS) by the NADPH oxidase OsRbohB during innate immunity. However, the molecular mechanism by which OsRac1 regulates OsRbohB remains unknown. Here, we report the crystal structure of OsRac1 complexed with the non-hydrolyzable GTP analog guanosine 5′-(β,γ-imido)triphosphate at 1.9 Å resolution; this represents the first active-form structure of a plant small GTPase. To elucidate the ROS production in rice cells, structural information was used to design OsRac1 mutants that displayed reduced binding to OsRbohB. Only mutations in the OsRac1 Switch I region showed attenuated interactions with OsRbohB in vitro. In particular, Tyr39 and Asp45 substitutions suppressed ROS production in rice cells, indicating that these residues are critical for interaction with and activation of OsRbohB. Structural comparison of active-form OsRac1 with AtRop9 in its GDP-bound inactive form showed a large conformational difference in the vicinity of these residues. Our results provide new insights into the molecular mechanism of the immune response through OsRac1 and the various cellular responses associated with plant Rac/Rop proteins. PMID:25128531

  7. Posterior tibial tendon impingement due to os subtibiale: a case report and up-to-date review.

    PubMed

    Turan, Adil; Kose, Ozkan; Acar, Baver; Unal, Melih

    2017-05-01

    Os subtibiale is a rare accessory ossicle located at the tip of the medial malleolus. Although this small ossicle usually has no clinical significance, in some cases it may be a source of ankle pain. Symptomatic os subtibiale is an extremely rare diagnosis, and few cases have been reported to date. The case presented is of a 35-year-old female patient with symptomatic os subtibiale, with a discussion of the diagnosis, clinical findings, and treatment options.

  8. Re-Os geochronology of Arctic black shales to evaluate the Anisian-Ladinian boundary and global faunal correlations

    NASA Astrophysics Data System (ADS)

    Xu, Guangping; Hannah, Judith L.; Stein, Holly J.; Bingen, Bernard; Yang, Gang; Zimmerman, Aaron; Weitschat, Wolfgang; Mørk, Atle; Weiss, Hermann M.

    2009-11-01

    Boreal and Tethyan faunas differ throughout the Triassic, limiting the use of biostratigraphy for global correlation. Rhenium-osmium (Re-Os) dating of organic-rich black shales, calibrated with existing biostratigraphy, provides a new means to establish correlations of global fauna using absolute time. Here we present Re-Os radiometric ages for Middle Triassic organic-rich shales from two biostratigraphically defined sections at Svalbard and the Svalis Dome in the Barents Sea. Mature black shales from Svalbard, inferred to be Middle to Late Anisian, define a 241.2 ± 2.2 Ma isochron with an initial 187Os/ 188Os ratio of 0.831 ± 0.025, the highest seawater Os isotope ratio yet recorded between the Cambrian and Lower Jurassic. Svalis Dome shales in the uppermost Anisian yield a 239.3 ± 2.7 Ma age and initial 187Os/ 188Os ratio of 0.679 ± 0.020. The higher initial 187Os/ 188Os ratio for Svalbard shales most likely reflects global seawater at the time of deposition, whereas the lower initial 187Os/ 188Os ratio for the Svalis Dome may represent seawater with limited communication to the open ocean, as suggested by the ratio of trace metal abundances and total organic carbon contents. These age data indicate a maximum age of 239.3 ± 2.7 Ma for the Anisian-Ladinian boundary in the Arctic Boreal realm. This age agrees with the proposed boundary in the Tethyan realm, 240 to 243 Ma, and thus confirms the correlations between Boreal and Tethys based on biostratigraphy and magnetostratigraphy. Our study affirms that Re-Os geochronology of black shale is a reliable method for obtaining depositional ages and establishing biostratigraphic correlations between paleogeographically separated regions.

  9. Re-Os isotope and platinum group elements of a FOcal ZOne mantle source, Louisville Seamounts Chain, Pacific ocean

    NASA Astrophysics Data System (ADS)

    Tejada, Maria Luisa G.; Hanyu, Takeshi; Ishikawa, Akira; Senda, Ryoko; Suzuki, Katsuhiko; Fitton, Godfrey; Williams, Rebecca

    2015-02-01

    The Louisville Seamount Chain (LSC) is, besides the Hawaiian-Emperor Chain, one of the longest-lived hotspot traces. We report here the first Re-Os isotope and platinum group element (PGE) data for Canopus, Rigil, and Burton Guyots along the chain, which were drilled during IODP Expedition 330. The LSC basalts possess (187Os/188Os)i = 0.1245-0.1314 that are remarkably homogeneous and do not vary with age. A Re-Os isochron age of 64.9 ± 3.2 Ma was obtained for Burton seamount (the youngest of the three seamounts drilled), consistent with 40Ar-39Ar data. Isochron-derived initial 187Os/188Os ratio of 0.1272 ± 0.0008, together with data for olivines (0.1271-0.1275), are within the estimated primitive mantle values. This (187Os/188Os)i range is similar to those of Rarotonga (0.124-0.139) and Samoan shield (0.1276-0.1313) basalts and lower than those of Cook-Austral (0.136-0.155) and Hawaiian shield (0.1283-0.1578) basalts, suggesting little or no recycled component in the LSC mantle source. The PGE data of LSC basalts are distinct from those of oceanic lower crust. Variation in PGE patterns can be largely explained by different low degrees of melting under sulfide-saturated conditions of the same relatively fertile mantle source, consistent with their primitive mantle-like Os and primordial Ne isotope signatures. The PGE patterns and the low 187Os/188Os composition of LSC basalts contrast with those of Ontong Java Plateau (OJP) tholeiites. We conclude that the Re-Os isotope and PGE composition of LSC basalts reflect a relatively pure deep-sourced common mantle sampled by some ocean island basalts but is not discernible in the composition of OJP tholeiites.

  10. Functional identification of a rice ent-kaurene oxidase, OsKO2, using the Pichia pastoris expression system.

    PubMed

    Ko, Kwang-Wook; Lin, Fengqiu; Katsumata, Takumi; Sugai, Yoshinori; Miyazaki, Sho; Kawaide, Hiroshi; Okada, Kazunori; Nojiri, Hideaki; Yamane, Hisakazu

    2008-12-01

    Rice ent-kaurene oxidase 2 (OsKO2) perhaps functions in the early steps of gibberellin biosynthesis. We found that microsomes from the methylotropic yeast Pichia pastoris expressing both OsKO2 and a fungal cytochrome P450 monooxygenase (P450) reductase converted ent-kaurene to ent-kaurenoic acid. This is direct evidence that OsKO2 is involved in the sequential oxidation of ent-kaurene to ent-kaurenoic acid in gibberellin biosynthesis in rice.

  11. Expression of OsCAS (Calcium-Sensing Receptor) in an Arabidopsis Mutant Increases Drought Tolerance.

    PubMed

    Zhao, Xin; Xu, Mengmeng; Wei, Rongrong; Liu, Yang

    2015-01-01

    The calcium-sensing receptor (CaS), which is localized in the chloroplasts, is a crucial regulator of extracellular calcium-induced stomatal closure in Arabidopsis. It has homologs in Oryza sativa and other plants. These sequences all have a rhodanese-like protein domain, which has been demonstrated to be associated with specific stress conditions. In this study, we cloned the Oryza sativa calcium-sensing receptor gene (OsCAS) and demonstrated that OsCAS could sense an increase of extracellular Ca2+ concentration and mediate an increase in cytosolic Ca2+ concentration. The OsCAS gene was transformed into an Arabidopsis CaS knockout mutant (Salk) and overexpressed in the transgenic plants. OsCAS promoted stomatal closure. We screened homozygous transgenic Arabidopsis plants and determined physiological indices such as the oxidative damage biomarker malondialdehyde (MDA), relative membrane permeability (RMP), proline content, and chlorophyll fluorescence parameters, after 21 days of drought treatment. Our results revealed lower RMP and MDA contents and a higher Proline content in transgenic Arabidopsis plants after drought stress, whereas the opposite was observed in Salk plants. With respect to chlorophyll fluorescence, the electron transport rate and effective PSII quantum yield decreased in all lines under drought stress; however, in the transgenic plants these two parameters changed fewer and were higher than those in wild-type and Salk plants. The quantum yield of regulated energy dissipation and nonregulated energy dissipation in PSII were higher in Salk plants, whereas these values were lower in the transgenic plants than in the wild type under drought stress. The above results suggest that the transgenic plants showed better resistance to drought stress by decreasing damage to the cell membrane, increasing the amount of osmoprotectants, and maintaining a relatively high photosynthetic capacity. In conclusion, OsCAS is an extracellular calcium-sensing receptor

  12. Distortion, interaction, and conceptual DFT perspectives of MO4-alkene (M = Os, Re, Tc, Mn) cycloadditions.

    PubMed

    Ess, Daniel H

    2009-02-20

    The reaction pathways (including the transition states) of ethylene addition to osmium tetroxide (OsO(4), and amine ligated), rhenate (ReO(4)(-)), technetate (TcO(4)(-)), and permanganate (MnO(4)(-)) have been studied by qualitative and quantitative analyses. Distortion/interaction and absolutely localized energy decomposition analyses provide new insights into why the (3 + 2) pathway is highly preferred over the (2 + 2) pathway, the origin of rate enhancement from ligated base, and reactivity differences between OsO(4), ReO(4)(-), TcO(4)(-), and MnO(4)(-). The (2 + 2) transition state has a much larger barrier than the (3 + 2) transition state because (1) the Os-O bond is stretched significantly resulting in a larger distortion energy (DeltaE(d)(double dagger)) value and (2) the transition state interaction energy (DeltaE(i)(double dagger)) is destabilizing due to large exchange repulsions overwhelming stabilizing charge-transfer terms. Base ligation lowers osmium tetroxide and ethylene distortion energies due to the ground-state O-Os-O angle being predistorted from 110 degrees to 103 degrees. Because MO(4) distortion energies are comparable, reactivity differences between OsO(4), ReO(4)(-), TcO(4)(-), and MnO(4)(-) is shown to be a function of ethylene to MO(4) charge-transfer. This interaction also dictates the position of the transition state along the reaction coordinate and corresponds to the onset of a stabilizing DeltaE(i)(double dagger) value. The conceptual DFT hardness profile and hardness response show that the (3 + 2) reaction pathway may be classified as an "allowed" pathway while the (2 + 2) reaction coordinate is best designated as "forbidden".

  13. Hexagonal OsB2 reduction upon heating in H2 containing environment

    SciTech Connect

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; Payzant, E. Andrew

    2014-10-23

    The stability of hexagonal ReB2 type OsB2 powder upon heating under reforming gas was investigated. Pure Os metal particles were detected by powder X-ray diffraction starting at 375⁰ C and complete transformation of OsB2 to metallic Os was observed at 725⁰ C. The mechanisms of precipitation of metallic Os is proposed and changes in the lattice parameters of OsB2 upon heating are analysed in terms of the presence of oxygen or water vapour in the heating chamber. Previous studies suggested that Os atoms possess (0) valence, while B atoms possess both (+3) and ( 3) valences in the alternating boron/osmium sheet structure of hexagonal (P63/mmc, No. 194) OsB2; if controllable method for Os removal from the lattice could be found, the opportunity would arise to form two-dimensional (2D) layers consisting of pure B atoms.

  14. Independent ordering of two interpenetrating magnetic sublattices in the double perovskite Sr2CoOsO6.

    PubMed

    Morrow, Ryan; Mishra, Rohan; Restrepo, Oscar D; Ball, Molly R; Windl, Wolfgang; Wurmehl, Sabine; Stockert, Ulrike; Büchner, Bernd; Woodward, Patrick M

    2013-12-18

    The insulating, fully ordered, double perovskite Sr2CoOsO6 undergoes two magnetic phase transitions. The Os(VI) ions order antiferromagnetically with a propagation vector k = (1/2, 1/2, 0) below TN1 = 108 K, while the high-spin Co(II) ions order antiferromagnetically with a propagation vector k = (1/2, 0, 1/2) below TN2 = 70 K. Ordering of the Os(VI) spins is accompanied by a structural distortion from tetragonal I4/m symmetry to monoclinic I2/m symmetry, which reduces the frustration of the face centered cubic lattice of Os(VI) ions. Density functional theory calculations show that the long-range Os-O-Co-O-Os and Co-O-Os-O-Co superexchange interactions are considerably stronger than the shorter Os-O-Co interactions. The poor energetic overlap between the 3d orbitals of Co and the 5d orbitals of Os appears to be responsible for this unusual inversion in the strength of short and long-range superexchange interactions.

  15. OsMYB511 encodes a MYB domain transcription activator early regulated by abiotic stress in rice.

    PubMed

    Huang, P; Chen, H; Mu, R; Yuan, X; Zhang, H S; Huang, J

    2015-08-14

    The MYB-domain proteins exist universally across diverse organisms and regulate numerous processes during the plant life cycle. In the present research, a full-length MYB gene OsMYB511 was identified from rice seedlings through microarray data. Induction of OsMYB511 by cold stress was dramatic in japonica cultivar Jiucaiqing as compared to indica IR26. In addition to cold, OsMYB511 was also markedly induced by osmotic stress, high temperature, and exogenous ABA, suggesting that OsMYB511 is a multiple-stress responsive gene in rice. Tissue-specific expression analysis indicated that OsMYB511 was highly expressed in rice panicles at earlier development stage. Interestingly, OsMYB511 expression is fully subjected to circadian rhythm regulation. The subcellular localization and yeast hybrid assay suggested that OsMYB511 is nucleus-localized transcription activator. Deletion analysis suggested that trans-activation activity of OsMYB511 relied on its C-terminus. Co-expression analysis revealed additional 2 MYB genes co-expressed with OsMYB511, implying that these MYB genes might coordinately regulate stress responses in rice.

  16. OsSLI1, a homeodomain containing transcription activator, involves abscisic acid related stress response in rice (Oryza sativa L.).

    PubMed

    Huang, Xi; Duan, Min; Liao, Jiakai; Yuan, Xi; Chen, Hui; Feng, Jiejie; Huang, Ji; Zhang, Hong-Sheng

    2014-01-01

    Homeodomain-leucine zipper type I (HD-Zip I) proteins are involved in the regulation of plant development and response to environmental stresses. In this study, OsSLI1 (Oryza sativa stress largely induced 1), encoding a member of the HD-Zip I subfamily, was isolated from rice. The expression of OsSLI1 was dramatically induced by multiple abiotic stresses and exogenous abscisic acid (ABA). In silico sequence analysis discovered several cis-acting elements including multiple ABREs (ABA-responsive element binding factors) in the upstream promoter region of OsSLI1. The OsSLI1-GFP fusion protein was localized in the nucleus of rice protoplast cells and the transcriptional activity of OsSLI1 was confirmed by the yeast hybrid system. Further, it was found that OsSLI1 expression was enhanced in an ABI5-Like1 (ABL1) deficiency rice mutant abl1 under stress conditions, suggesting that ABL1 probably negatively regulates OsSLI1 gene expression. Moreover, it was found that OsSLI1 was regulated in panicle development. Taken together, OsSLI1 may be a transcriptional activator regulating stress-responsive gene expression and panicle development in rice.

  17. OsSIDP366, a DUF1644 gene, positively regulates responses to drought and salt stresses in rice.

    PubMed

    Guo, Chiming; Luo, Chengke; Guo, Lijia; Li, Min; Guo, Xiaoling; Zhang, Yuxia; Wang, Liangjiang; Chen, Liang

    2016-05-01

    Domain of unknown function 1644 (DUF1644) is a highly conserved amino acid sequence motif present only in plants. Analysis of expression data of the family of DUF1644-containing genes indicated that they may regulate responses to abiotic stress in rice. Here we present our discovery of the role of OsSIDP366, a member of the DUF1644 gene family, in response to drought and salinity stresses in rice. Transgenic rice plants overexpressing OsSIDP366 showed enhanced drought and salinity tolerance and reduced water loss as compared to that in the control, whereas plants with downregulated OsSIDP366 expression levels using RNA interference (RNAi) were more sensitive to salinity and drought treatments. The sensitivity to abscisic acid (ABA) treatment was not changed in OsSIDP366-overexpressing plants, and OsSIDP366 expression was not affected in ABA-deficient mutants. Subcellular localization analysis revealed that OsSIDP366 is presented in the cytoplasmic foci that colocalized with protein markers for both processing bodies (PBs) and stress granules (SGs) in rice protoplasts. Digital gene expression (DGE) profile analysis indicated that stress-related genes such as SNAC1, OsHAK5 and PRs were upregulated in OsSIDP366-overexpressing plants. These results suggest that OsSIDP366 may function as a regulator of the PBs/SGs and positively regulate salt and drought resistance in rice.

  18. Overexpression of OsEm1 encoding a group I LEA protein confers enhanced drought tolerance in rice.

    PubMed

    Yu, Jing; Lai, Yongmin; Wu, Xi; Wu, Gang; Guo, Changkui

    2016-09-16

    Drought is the greatest threat for crops, including rice. In an effort to identify rice genes responsible for drought tolerance, a drought-responsive gene OsEm1 encoding a group I LEA protein, was chosen for this study. OsEm1 was shown at vegetative stages to be responsive to various abiotic stresses, including drought, salt, cold and the hormone ABA. In this study, we generated OsEm1-overexpressing rice plants to explore the function of OsEm1 under drought conditions. Overexpression of OsEm1 increases ABA sensitivity and enhances osmotic tolerance in rice. Compared with wild type, the OsEm1-overexpressing rice plants showed enhanced plant survival ratio at the vegetative stage; moreover, over expression of OsEm1 in rice increased the expression of other LEA genes, including RAB16A, RAB16C, RAB21, and LEA3, likely protecting organ integrity against harsh environments. Interestingly, the elevated level of OsEm1 had no different phenotype compared with wild type under normal condition. Our findings suggest that OsEm1 is a positive regulator of drought tolerance and is potentially promising for engineering drought tolerance in rice.

  19. Functions of OsBZR1 and 14-3-3 proteins in brassinosteroid signaling in rice

    PubMed Central

    Bai, Ming-Yi; Zhang, Li-Ying; Gampala, Srinivas S.; Zhu, Sheng-Wei; Song, Wen-Yuan; Chong, Kang; Wang, Zhi-Yong

    2007-01-01

    Brassinosteroids (BR) are essential growth hormones found throughout the plant kingdom. BR bind to the receptor kinase BRI1 on the cell surface to activate a signal transduction pathway that regulates nuclear gene expression and plant growth. To understand the downstream BR signaling mechanism in rice, we studied the function of OsBZR1 using reverse genetic approaches and identified OsBZR1-interacting proteins. Suppressing OsBZR1 expression by RNAi resulted in dwarfism, erect leaves, reduced BR sensitivity, and altered BR-responsive gene expression in transgenic rice plants, demonstrating an essential role of OsBZR1 in BR responses in rice. Moreover, a yeast two-hybrid screen identified 14-3-3 proteins as OsBZR1-interacting proteins. Mutation of a putative 14-3-3-binding site of OsBZR1 abolished its interaction with the 14-3-3 proteins in yeast and in vivo. Such mutant OsBZR1 proteins suppressed the phenotypes of the Arabidopsis bri1–5 mutant and showed an increased nuclear distribution compared with the wild-type protein, suggesting that 14-3-3 proteins directly inhibit OsBZR1 function at least in part by reducing its nuclear localization. These results demonstrate a conserved function of OsBZR1 and an important role of 14-3-3 proteins in brassinosteroid signal transduction in rice. PMID:17699623

  20. MADS-box transcription factor OsMADS25 regulates root development through affection of nitrate accumulation in rice.

    PubMed

    Yu, Chunyan; Liu, Yihua; Zhang, Aidong; Su, Sha; Yan, An; Huang, Linli; Ali, Imran; Liu, Yu; Forde, Brian G; Gan, Yinbo

    2015-01-01

    MADS-box transcription factors are vital regulators participating in plant growth and development process and the functions of most of them are still unknown. ANR1 was reported to play a key role in controlling lateral root development through nitrate signal in Arabidopsis. OsMADS25 is one of five ANR1-like genes in Oryza Sativa and belongs to the ANR1 clade. Here we have investigated the role of OsMADS25 in the plant's responses to external nitrate in Oryza Sativa. Our results showed that OsMADS25 protein was found in the nucleus as well as in the cytoplasm. Over-expression of OsMADS25 significantly promoted lateral and primary root growth as well as shoot growth in a nitrate-dependent manner in Arabidopsis. OsMADS25 overexpression in transgenic rice resulted in significantly increased primary root length, lateral root number, lateral root length and shoot fresh weight in the presence of nitrate. Down-regulation of OsMADS25 in transgenic rice exhibited significantly reduced shoot and root growth in the presence of nitrate. Furthermore, over-expression of OsMADS25 in transgenic rice promoted nitrate accumulation and significantly increased the expressions of nitrate transporter genes at high rates of nitrate supply while down-regulation of OsMADS25 produced the opposite effect. Taken together, our findings suggest that OsMADS25 is a positive regulator control lateral and primary root development in rice.

  1. The ethylene response factor OsERF109 negatively affects ethylene biosynthesis and drought tolerance in rice.

    PubMed

    Yu, Yanwen; Yang, Dexin; Zhou, Shirong; Gu, Juntao; Wang, Fengru; Dong, Jingao; Huang, Rongfeng

    2017-01-01

    Drought is an important factor limiting plant development and crop production. Dissecting the factors involved in this process is the key for enhancement of plant tolerance to drought stress by genetic approach. Here, we evaluated the regulatory function of a novel rice ethylene response factor (ERF) OsERF109 in drought stress. Expression of OsERF109 was rapidly induced by stress and phytohormones. Subcellular localization and transactivation assay demonstrated that OsERF109 was localized in nucleus and possessed transactivation activity. Transgenic plants overexpressing (OE) and knockdown with RNA interfering (RI) OsERF109 exhibited significantly reduced and improved drought resistance, respectively, indicating that OsERF109 negatively regulates drought resistance in rice. Furthermore, measurement by gas chromatography showed that ethylene contents were less in OE while more in RI lines than these in wild types, supporting the data of drought tolerance and water loss in transgenic lines. Quantitative real-time PCR analysis also proved the regulation of OsERF109 in the expression of OSACS6, OSACO2, and OsERF3, which have been identified to play important roles in ethylene biosynthesis. Based on these results, our data evidence that OsERF109 regulates drought resistance by affecting the ethylene biosynthesis in rice. Overall, our study reveals the negative role of OsERF109 in ethylene biosynthesis and drought tolerance in rice.

  2. OsLOX2, a rice type I lipoxygenase, confers opposite effects on seed germination and longevity.

    PubMed

    Huang, Jiexue; Cai, Maohong; Long, Qizhang; Liu, Linglong; Lin, Qiuyun; Jiang, Ling; Chen, Saihua; Wan, Jianmin

    2014-08-01

    Rice production and seed storage are confronted with grain deterioration and loss of seed viability. Some members of the lipoxygenase (LOX) family function in degradation of storage lipids during the seed germination, but little is known about their influence on seed longevity during storage. We characterized the role of rice OsLOX2 gene in seed germination and longevity via over-expression and knock-down approaches. Abundant expression of OsLOX2 was detected in panicles, roots, and stems, but not in leaves. Moreover, OsLOX2 was highly induced during germination. OsLOX2 protein, located in the cytoplasm, showed a wide range of temperature adaptation (20-50 °C) and a substrate preference to linoleic acid. Lines over-expressing OsLOX2 showed accelerated seed germination under normal condition and lower seed viability after accelerated aging. RNA interference (RNAi) of OsLOX2 caused delayed germination and enhanced seed longevity. RNAi lines with strongly repressed OsLOX2 activity completely lost the capability of germination after accelerated aging. More lipid hydroperoxide were found in OE15 than the control, but less in RNAi lines than in the WT Nipponbare. Therefore, OsLOX2 acts in opposite directions during seed germination and longevity during storage. Appropriate repression of the OsLOX2 gene may delay the aging process during the storage without compromising germination under normal conditions.

  3. Density functional theory study of structural, electronic, and thermal properties of Pt, Pd, Rh, Ir, Os and PtPd X (X = Ir, Os, and Rh) alloys

    NASA Astrophysics Data System (ADS)

    Shabbir, Ahmed; Muhammad, Zafar; M, Shakil; M, A. Choudhary

    2016-03-01

    The structural, electronic, mechanical, and thermal properties of Pt, Pd, Rh, Ir, Os metals and their alloys PtPdX (X = Ir, Os and Rh) are studied systematically using ab initio density functional theory. The groundstate properties such as lattice constant and bulk modulus are calculated to find the equilibrium atomic position for stable alloys. The electronic band structure and density of states are calculated to study the electronic behavior of metals on making their alloys. The electronic properties substantiate the metallic behavior for all studied materials. The firstprinciples density functional perturbation theory as implemented in quasi-harmonic approximation is used for the calculations of thermal properties. We have calculated the thermal properties such as the Debye temperature, vibrational energy, entropy and constant-volume specific heat. The calculated properties are compared with the previously reported experimental and theoretical data for metals and are found to be in good agreement. Calculated results for alloys could not be compared because there is no data available in the literature with such alloy composition.

  4. Overexpression of OsRecQl4 and/or OsExo1 enhances DSB-induced homologous recombination in rice.

    PubMed

    Kwon, Yong-Ik; Abe, Kiyomi; Osakabe, Keishi; Endo, Masaki; Nishizawa-Yokoi, Ayako; Saika, Hiroaki; Shimada, Hiroaki; Toki, Seiichi

    2012-12-01

    During homologous recombination (HR)-mediated DNA double-strand break (DSB) repair in eukaryotes, an initial step is the creation of a 3'-single-stranded DNA (ssDNA) overhang via resection of a 5' end. Rad51 polymerizes on this ssDNA to search for a homologous sequence, and the gapped sequence is then repaired using an undamaged homologous DNA strand as template. Recent studies in eukaryotes indicate that resection of the DSB site is promoted by the cooperative action of RecQ helicase family proteins: Bloom helicase (BLM) in mammals or Sgs1 in yeast, and exonuclease 1 (Exo1). However, the role of RecQ helicase and exonuclease during the 5'-resection process of HR in plant cells has not yet been defined. Here, we demonstrate that overexpression of rice proteins OsRecQl4 (BLM counterpart) and/or OsExo1 (Exo1 homolog) can enhance DSB processing, as evaluated by recombination substrate reporter lines in rice. These results could be applied to construct an efficient gene targeting system in rice.

  5. In situ Re-Os isotopic analysis of platinum-group minerals from the Mayarí-Cristal ophiolitic massif (Mayarí-Baracoa Ophiolitic Belt, eastern Cuba): implications for the origin of Os-isotope heterogeneities in podiform chromitites

    NASA Astrophysics Data System (ADS)

    Marchesi, Claudio; González-Jiménez, José María; Gervilla, Fernando; Garrido, Carlos J.; Griffin, William L.; O'Reilly, Suzanne Y.; Proenza, Joaquín A.; Pearson, Norman J.

    2011-06-01

    Chromitite pods in the Mayarí-Cristal ophiolitic massif (eastern Cuba) were formed in the Late Cretaceous when island arc tholeiites and MORB-like back-arc basin basalts reacted with residual mantle peridotites and generated chromite-rich bodies enclosed in dunite envelopes. Platinum-group minerals (PGM) in the podiform chromitites exhibit important Os-isotope heterogeneities at the kilometric, hand sample and thin section scales. 187Os/188Os calculated at the time of chromitite crystallization (~90 Ma) ranges between 0.1185 and 0.1295 (γOs = -7.1 to +1.6, relative to enstatite chondrite), and all but one PGM have subchondritic 187Os/188Os. Grains in a single hand sample have initial 187Os/188Os that spans from 0.1185 to 0.1274, and in one thin section it varies between 0.1185 and 0.1232 in two PGM included in chromite which are only several millimeters apart. As the Os budget of a single micrometric grain derives from a mantle region that was at least several m3 in size, the variable Os isotopic composition of PGM in the Mayarí-Cristal chromitites probably reflects the heterogeneity of their mantle sources on the 10-100 m scale. Our results show that this heterogeneity was not erased by pooling and mingling of individual melt batches during chromitite crystallization but was transferred to the ore deposits on mineral scale. The distribution of the Os model ages calculated for PGM shows four main peaks, at ~100, 500, 750 and 1,000 Ma. These variable Os model ages reflect the presence of different depleted domains in the oceanic (Pacific-related) upper mantle of the Greater Antilles paleo-subduction zone. The concordance between the age of crystallization of the Mayarí-Cristal chromitites and the most recent peak of the Os model age distribution in PGM supports that Os in several grains was derived from fertile domains of the upper mantle, whose bulk Os isotopic composition is best approximated by that of enstatite chondrites; on the other hand, most PGM are

  6. Syntheses, structures and redox properties of some complexes containing the Os(dppe)Cp* fragment, including [{Os(dppe)Cp*}2(mu-C triple bondCC triple bond C)].

    PubMed

    Bruce, Michael I; Costuas, Karine; Davin, Thomas; Halet, Jean-François; Kramarczuk, Kathy A; Low, Paul J; Nicholson, Brian K; Perkins, Gary J; Roberts, Rachel L; Skelton, Brian W; Smith, Mark E; White, Allan H

    2007-12-14

    The sequential conversion of [OsBr(cod)Cp*] (9) to [OsBr(dppe)Cp*] (10), [Os([=C=CH2)(dppe)Cp*]PF6 ([11]PF6), [Os(C triple bond CH)(dppe)Cp*] (12), [{Os(dppe)Cp*}2{mu-(=C=CH-CH=C=)}][PF6]2 ([13](PF6)2) and finally [{Os(dppe)Cp*}(2)(mu-C triple bond CC triple bond C)] (14) has been used to make the third member of the triad [{M(dppe)Cp*}2(mu-C triple bond CC triple bond C)] (M = Fe, Ru, Os). The molecular structures of []PF6, 12 and 14, together with those of the related osmium complexes [Os(NCMe)(dppe)Cp*]PF6 ([15]PF6) and [Os(C triple bond CPh)(dppe)Cp*] (16), have been determined by single-crystal X-ray diffraction studies. Comparison of the redox properties of 14 with those of its iron and ruthenium congeners shows that the first oxidation potential E1 varies as: Fe approximately Os < Ru. Whereas the Fe complex has been shown to undergo three sequential 1-electron oxidation processes within conventional electrochemical solvent windows, the Ru and Os compounds undergo no fewer than four sequential oxidation events giving rise to a five-membered series of redox related complexes [{M(dppe)Cp*}2(mu-C4)]n+ (n = 0, 1, 2, 3 and 4), the osmium derivatives being obtained at considerably lower potentials than the ruthenium analogues. These results are complimented by DFT and DT DFT calculations.

  7. Resolving mantle and magmatic processes in basalts from the Cameroon volcanic line using the Re-Os isotope system

    NASA Astrophysics Data System (ADS)

    Gannoun, A.; Burton, K. W.; Barfod, D. N.; Schiano, P.; Vlastélic, I.; Halliday, A. N.

    2015-05-01

    This study presents major-, trace element and Re-Os isotope and elemental data for young alkaline basalts (< 10 Ma) from oceanic (Annobon, S. Tomé, Principe), continental (Manengouba) and continent-oceanic boundary (COB, Mt. Cameroon) sectors of the Cameroon volcanic line (CVL). The CVL is a chain of Tertiary to recent, transitional to strongly alkaline intraplate volcanoes extending from the south Atlantic island of Annobon to the continental interior of West Africa (Biu Plateau). The basalts from the oceanic sector display a range of initial 187Os/188Os ratios between 0.128 and 0.190 and those from the COB and continental sector range between 0.142 and 0.560. The samples with high 206Pb/204Pb (e.g. ratios > 20) possess 187Os/188Os isotope compositions between 0.14 and 0.18 (e.g., basalts from Mt Cameroon and Sao Tomé) which reflect the chemical characteristics that are more likely to be primary features of CVL, and are close to the value of 0.153 attributed to the HIMU end-member (Tubuai-Mangaia). However, most of the lavas from the continental sector show highly radiogenic initial 187Os/188Os ratios (0.36 to 0.56) that are outside the range previously observed for ocean island basalts, with shifts to radiogenic Os isotope compositions accompanied by less radiogenic 206Pb/204Pb and increasing SiO2 contents. The increase in 187Os/188Os is also associated with the decrease of Os, Ni, MgO and phenocryst abundances. These data can be explained by fractional crystallisation and assimilation of continental crust by the ascending magma. The systematic shift to unradiogenic lead isotope compositions from the COB into the oceanic sector is positively correlated with variations in 187Os/188Os isotope composition (from 0.140 to 0.128). At first sight this covariation might be attributed to the mixing of HIMU material with the ambient upper mantle (DMM). However, there is a clear covariation of the Os isotope and elemental composition, best explained with contamination of

  8. Suppression of OsRAD51D results in defects in reproductive development in rice (Oryza sativa L.).

    PubMed

    Byun, Mi Young; Kim, Woo Taek

    2014-07-01

    The cellular roles of RAD51 paralogs in somatic and reproductive growth have been extensively described in a wide range of animal systems and, to a lesser extent, in Arabidopsis, a dicot model plant. Here, the OsRAD51D gene was identified and characterized in rice (Oryza sativa L.), a monocot model crop. In the rice genome, three alternative OsRAD51D mRNA splicing variants, OsRAD51D.1, OsRAD51D.2, and OsRAD51D.3, were predicted. Yeast two-hybrid studies, however, showed that only OsRAD51D.1 interacted with OsRAD51B and OsRAD51C paralogs, suggesting that OsRAD51D.1 is a functional OsRAD51D protein in rice. Loss-of-function osrad51d mutant rice plants displayed normal vegetative growth. However, the mutant plants were defective in reproductive growth, resulting in sterile flowers. Homozygous osrad51d mutant flowers exhibited impaired development of lemma and palea and contained unusual numbers of stamens and stigmas. During early meiosis, osrad51d pollen mother cells (PMCs) failed to form normal homologous chromosome pairings. In subsequent meiotic progression, mutant PMCs represented fragmented chromosomes. The osrad51d pollen cells contained numerous abnormal micro-nuclei that resulted in malfunctioning pollen. The abnormalities of heterozygous mutant and T2 Ubi:RNAi-OsRAD51D RNAi-knock-down transgenic plants were intermediate between those of wild type and homozygous mutant plants. The osrad51d and Ubi:RNAi-OsRAD51D plants contained longer telomeres compared with wild type plants, indicating that OsRAD51D is a negative factor for telomere lengthening. Overall, these results suggest that OsRAD51D plays a critical role in reproductive growth in rice. This essential function of OsRAD51D is distinct from Arabidopsis, in which AtRAD51D is not an essential factor for meiosis or reproductive development.

  9. Rice phytochrome-interacting factor protein OsPIFff14 represses OsDREB1B gene expression through an extended N-box and interacts preferentially with the active form of phytochrome B

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a Yeast one Hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bi...

  10. Genome-Wide Targets Regulated by the OsMADS1 Transcription Factor Reveals Its DNA Recognition Properties1[OPEN

    PubMed Central

    Khanday, Imtiyaz; Das, Sanjukta; Chongloi, Grace L; Vijayraghavan, Usha

    2016-01-01

    OsMADS1 controls rice (Oryza sativa) floral fate and organ development. Yet, its genome-wide targets and the mechanisms underlying its role as a transcription regulator controlling developmental gene expression are unknown. We identify 3112 gene-associated OsMADS1-bound sites in the floret genome. These occur in the vicinity of transcription start sites, within gene bodies, and in intergenic regions. Majority of the bound DNA contained CArG motif variants or, in several cases, only A-tracts. Sequences flanking the binding peak had a higher AT nucleotide content, implying that broader DNA structural features may define in planta binding. Sequences for binding by other transcription factor families like MYC, AP2/ERF, bZIP, etc. are enriched in OsMADS1-bound DNAs. Target genes implicated in transcription, chromatin remodeling, cellular processes, and hormone metabolism were enriched. Combining expression data from OsMADS1 knockdown florets with these DNA binding data, a snapshot of a gene regulatory network was deduced where targets, such as AP2/ERF and bHLH transcription factors and chromatin remodelers form nodes. We show that the expression status of these nodal factors can be altered by inducing the OsMADS1-GR fusion protein and present a model for a regulatory cascade where the direct targets of OsMADS1, OsbHLH108/SPT, OsERF034, and OsHSF24, in turn control genes such as OsMADS32 and OsYABBY5. This cascade, with other similar relationships, cumulatively contributes to floral organ development. Overall, OsMADS1 binds to several regulatory genes and, probably in combination with other factors, controls a gene regulatory network that ensures rice floret development. PMID:27457124

  11. Genetic Transformation and Analysis of Rice OsAPx2 Gene in Medicago sativa

    PubMed Central

    Guan, Qingjie; Takano, Tetsuo; Liu, Shenkui

    2012-01-01

    The OsAPx2 gene from rice was cloned to produce PBI121::OsAPx2 dual-expression plants, of which expression level would be increasing under stressful conditions. The enzyme ascorbate peroxidase (APX) in the leaves and roots of the plants increased with increasing exposure time to different sodium chloride (NaCl) and hydrogen peroxide (H2O2)concentrations, as indicated by protein gel blot analysis. The increased enzyme yield improved the ability of the plants to resist the stress treatments. The OsAPx2 gene was localized in the cytoplasm of epidermal onion cells as indicated by the instantaneous expression of green fluorescence. An 80% regeneration rate was observed in Medicago sativa L. plants transformed with the OsAPx2 gene using Agrobacterium tumefaciens, as indicated by specific primer PCR. The OsAPx2 gene was expressed at the mRNA level and the individual M. sativa (T#1,T#2,T#5) were obtained through assaying the generation of positive T2 using RNA gel blot analysis. When the seeds of the wild type (WT) and the T2 (T#1,T#5) were incubated in culture containing MS with NaCl for 7 days, the results as shown of following: the root length of transgenic plant was longer than WT plants, the H2O2 content in roots of WT was more than of transgenic plants, the APX activity under stresses increased by 2.89 times compared with the WT, the malondialdehyde (MDA) content of the WT was higher than the transgenic plants, the leaves of the WT turned yellow, but those of the transgenic plants remained green and remained healthy. The chlorophyll content in the WT leaves was less than in the transgenic plants, after soaking in solutions of H2O2, sodium sulfite (Na2SO3), and sodium bicarbonate (NaHCO3). Therefore, the OsAPx2 gene overexpression in transgenic M. sativa improves the removal of H2O2 and the salt-resistance compared with WT plants. A novel strain of M. sativa carrying a salt-resistance gene was obtained. PMID:22848448

  12. Genetic transformation and analysis of rice OsAPx2 gene in Medicago sativa.

    PubMed

    Guan, Qingjie; Takano, Tetsuo; Liu, Shenkui

    2012-01-01

    The OsAPx2 gene from rice was cloned to produce PBI121::OsAPx2 dual-expression plants, of which expression level would be increasing under stressful conditions. The enzyme ascorbate peroxidase (APX) in the leaves and roots of the plants increased with increasing exposure time to different sodium chloride (NaCl) and hydrogen peroxide (H(2)O(2))concentrations, as indicated by protein gel blot analysis. The increased enzyme yield improved the ability of the plants to resist the stress treatments. The OsAPx2 gene was localized in the cytoplasm of epidermal onion cells as indicated by the instantaneous expression of green fluorescence. An 80% regeneration rate was observed in Medicago sativa L. plants transformed with the OsAPx2 gene using Agrobacterium tumefaciens, as indicated by specific primer PCR. The OsAPx2 gene was expressed at the mRNA level and the individual M. sativa (T#1,T#2,T#5) were obtained through assaying the generation of positive T2 using RNA gel blot analysis. When the seeds of the wild type (WT) and the T2 (T#1,T#5) were incubated in culture containing MS with NaCl for 7 days, the results as shown of following: the root length of transgenic plant was longer than WT plants, the H(2)O(2) content in roots of WT was more than of transgenic plants, the APX activity under stresses increased by 2.89 times compared with the WT, the malondialdehyde (MDA) content of the WT was higher than the transgenic plants, the leaves of the WT turned yellow, but those of the transgenic plants remained green and remained healthy. The chlorophyll content in the WT leaves was less than in the transgenic plants, after soaking in solutions of H(2)O(2), sodium sulfite (Na(2)SO(3)), and sodium bicarbonate (NaHCO(3)). Therefore, the OsAPx2 gene overexpression in transgenic M. sativa improves the removal of H(2)O(2) and the salt-resistance compared with WT plants. A novel strain of M. sativa carrying a salt-resistance gene was obtained.

  13. Synthesis, characterization and crystal structure of a novel Os(II)-supported tungstoarsenate [HAsW{sub 7}O{sub 28}Os(dmso){sub 3}]{sup 6-}

    SciTech Connect

    Bi Lihua Li Bao; Wu Lixin Shao Kuizhan; Su Zhongmin

    2009-01-15

    Reaction of tri-lacunary Keggin tungstoarsenate with osmium complex Os(dmso){sub 4}Cl{sub 2} under mild condition led to the formation of a novel Os (II)-supported tungstoarsenate Na{sub 5}(NH{sub 4})[HAsW{sub 7}O{sub 28}Os(dmso){sub 3}].15H{sub 2}O (1a). Single-crystal X-ray diffraction analysis shows that compound 1a crystallizes in the monoclinic space group P2{sub 1}/c (no. 14) with a=14.9166(12) A, b=23.6935(19) A, c=16.5349(14) A, {beta}=92.7950(10){sup o}, V=5836.9(8) A{sup 3}, Z=4 with R{sub 1}=0.0453. The crystal structure reveals two features: (1) the polyanion [HAsW{sub 7}O{sub 28}Os(dmso){sub 3}]{sup 6-} (1) consists of a Os(dmso){sub 3} unit linked to a tungstoarsenate fragment {l_brace}HAsW{sub 7}O{sub 28}{r_brace} via two Os-O-W bonds and one Os-O-As bond resulting in an assembly with C{sub s} symmetry, which represents a novel mode of Os-coordination to a polyoxoanion framework; (2) 3D architecture assembled by the polyanion 1 and sodium linkers. In addition, the compound 1a was well characterized by the multinuclear NMR ({sup 13}C, {sup 1}H), IR spectroscopy, UV-vis spectroscopy, elemental analysis, and cyclic voltammetry (CV). - Graphical abstract: A new tungstoarsenate containing a Os(dmso){sub 3} unit [HAsW{sub 7}O{sub 28}Os(dmso){sub 3}]{sup 6-} (1) has been synthesized using [HAsW{sub 9}O{sub 34}]{sup 8-} as polyanion precursor and structurally characterized.

  14. Nucleus deformation of SaOs-2 cells on rhombic µ-pillars.

    PubMed

    Eichhorn, Melanie; Stannard, Cleo; Anselme, Karine; Rühe, Jürgen

    2015-02-01

    It has been previously shown that osteosarcoma (SaOs-2) cells respond to micropillared surfaces consisting of poly-L-lactic acid with strong deformation of the cell body and nucleus. Until now, cell nucleus deformation of SaOs-2 cells was only studied by exposing them to square shaped micropillars in an isotropic pattern. Here we report on experiments of the cell nucleus response of such cells to rhombic structures of different topographies generated from a rubbery polymer, namely poly(n-butyacrylate). It is observed that cells orientate themselves perpendicular to the long axis of the rhombi. While their spreading on the surface is not influenced by the opening angle of the structures, rhombic structures with sharper angles induce stronger deformation of the cells and accordingly more elongated nuclei.

  15. X11---A graphic interface in the OS-9 real-time environment

    SciTech Connect

    Pastore, A. )

    1990-08-01

    X11 is a graphic window manager developed as a joint project of the Masschusetts Institute of Technology and Digital Equipment Corporation. It represents a widely available platform to develop distributed graphic applications using TCP/IP and DECNET. Microware's OS-9 is a real-time operating system widely used inside the physics community. The marriage between OS-9 and X11 should be seen as an attempt to stabilize a wise, open and accepted platform in the physics world to do real-time programming as well as line graphic output. Choosing X11 as our graphic environment should allow applications to run virtually without changes for several years but still be able to use the latest and fastest CPUs/architectures.

  16. Microscopic structure of low-lying states in {sup 188,190,192}Os

    SciTech Connect

    Lo Iudice, N.; Sushkov, A. V.

    2008-11-15

    The phonon and quasiparticle structure of the low-lying states in {sup 188,190,192}Os is investigated within the microscopic quasiparticle-phonon model. An overall agreement with the data is obtained for energies and transitions. The properties of the 0{sup +} states are found to be correlated with the evolution of the nuclear shape toward the {gamma}-soft region. Special attention is devoted at the 4{sub 3}{sup +} state. This state is found to be composed of a large double-{gamma} phonon component coexisting with an even larger one-phonon hexadecapole piece. Such a mixed phonon structure explains the observed, apparently contradictory, properties of the 4{sub 3}{sup +} states in Os isotopes.

  17. The origin of hyperferroelectricity in LiBO3 (B = V, Nb, Ta, Os)

    NASA Astrophysics Data System (ADS)

    Li, Pengfei; Ren, Xinguo; Guo, Guang-Can; He, Lixin

    2016-10-01

    The electronic and structural properties of LiBO3 (B = V, Nb, Ta, Os) are investigated via first-principles methods. We show that LiBO3 belong to the recently proposed hyperferroelectrics (hyperFEs), i.e., they all have unstable longitudinal optic phonon modes. Especially, the ferroelectric-like instability in the metal LiOsO3, whose optical dielectric constant goes to infinity, is a limiting case of hyperFEs. Via an effective Hamiltonian, we further show that, in contrast to normal proper ferroelectricity, in which the ferroelectric instability usually comes from long-range coulomb interactions, the hyperFE instability is due to the structure instability driven by short-range interactions. This could happen in systems with large ion size mismatches, which therefore provides a useful guidance in searching for novel hyperFEs.

  18. Spin-orbit coupling controlled ground state in Sr2ScOsO6

    NASA Astrophysics Data System (ADS)

    Taylor, A. E.; Morrow, R.; Fishman, R. S.; Calder, S.; Kolesnikov, A. I.; Lumsden, M. D.; Woodward, P. M.; Christianson, A. D.

    2016-06-01

    We report neutron scattering experiments which reveal a large spin gap in the magnetic excitation spectrum of weakly-monoclinic double perovskite Sr2ScOsO6 . The spin gap is demonstrative of appreciable spin-orbit-induced anisotropy, despite nominally orbitally-quenched 5 d3Os5 + ions. The system is successfully modeled including nearest neighbor interactions in a Heisenberg Hamiltonian with exchange anisotropy. We find that the presence of the spin-orbit-induced anisotropy is essential for the realization of the type I antiferromagnetic ground state. This demonstrates that physics beyond the LS or JJ coupling limits plays an active role in determining the collective properties of 4 d3 and 5 d3 systems and that theoretical treatments must include spin-orbit coupling.

  19. B11 NMR in the layered diborides OsB2 and RuB2

    NASA Astrophysics Data System (ADS)

    Suh, B. J.; Zong, X.; Singh, Y.; Niazi, A.; Johnston, D. C.

    2007-10-01

    B11 nuclear magnetic resonance (NMR) measurements have been performed on B11 enriched OsB2 and RuB2 polycrystalline powder samples in an external field of 4.7T and in the temperature range, 4.2KOsB2 and RuB2 , respectively. The experimental results indicate that a p character dominates the conduction electron wave function at the B site with a negligibly small s character in both compounds.

  20. OsSDS is essential for DSB formation in rice meiosis.

    PubMed

    Wu, Zhigang; Ji, Jianhui; Tang, Ding; Wang, Hongjun; Shen, Yi; Shi, Wenqing; Li, Yafei; Tan, Xuelin; Cheng, Zhukuan; Luo, Qiong

    2015-01-01

    SDS is a meiosis specific cyclin-like protein and required for DMC1 mediated double-strand break (DSB) repairing in Arabidopsis. Here, we found its rice homolog, OsSDS, is essential for meiotic DSB formation. The Ossds mutant is normal in vegetative growth but both male and female gametes are inviable. The Ossds meiocytes exhibit severe defects in homologous pairing and synapsis. No γH2AX immunosignals in Ossds meiocytes together with the suppression of chromosome fragmentation in Ossds-1 Osrad51c, both provide strong evidences that OsSDS is essential for meiotic DSB formation. Immunostaining investigations revealed that meiotic chromosome axes are normally formed but both SC installation and localization of recombination elements are failed in Ossds. We suspected that this cyclin protein has been differentiated pretty much between monocots and dicots on its function in meiosis.

  1. [A malformation to know: os odontoideum. Report on two pediatric cases].

    PubMed

    Cherradi Lachhab, I; Dafiri, R

    2014-04-01

    The os odontoideum, or mobile odontoid apophysis, is a malformation of the cervico-occipital hinge caused by missing unity in the ossification center of the dens on the body of the axis. This malformation induces atloaxial instability and exposes the subject to the risk of bulbar-medullary compression. The true incidence of this condition is difficult to determine because many cases are asymptomatic. The pathogenesis is discussed. Congenital and traumatic theories have been advanced. Clinically, the defect can be discovered incidentally or revealed by neck pain, a stiff neck, dizziness, or deficient syndrome. CT and MRI imaging can detect the defects, and allow one to study the impact on the contents of the spinal canal and detect lesions. We report two new os odontoideum observations in children aged 5 and 14 years who were referred for equilibrium disorders and tetraparesis, respectively.

  2. Spin-orbit coupling controlled ground state in Sr2ScOsO6

    DOE PAGES

    Taylor, A. E.; Morrow, R.; Fishman, R. S.; ...

    2016-06-27

    In this paper, we report neutron scattering experiments which reveal a large spin gap in the magnetic excitation spectrum of weakly-monoclinic double perovskite Sr2ScOsO6. The spin gap is demonstrative of appreciable spin-orbit-induced anisotropy, despite nominally orbitally-quenched 5d3Os5+ ions. The system is successfully modeled including nearest neighbor interactions in a Heisenberg Hamiltonian with exchange anisotropy. We find that the presence of the spin-orbit-induced anisotropy is essential for the realization of the type I antiferromagnetic ground state. Finally, this demonstrates that physics beyond the LS or JJ coupling limits plays an active role in determining the collective properties of 4d3 and 5d3more » systems and that theoretical treatments must include spin-orbit coupling.« less

  3. Correlation between microstructure and thermionic electron emission from Os-Ru thin films on dispenser cathodes

    SciTech Connect

    Swartzentruber, Phillip D.; John Balk, Thomas; Effgen, Michael P.

    2014-07-01

    Osmium-ruthenium films with different microstructures were deposited onto dispenser cathodes and subjected to 1000 h of close-spaced diode testing. Tailored microstructures were achieved by applying substrate biasing during deposition, and these were evaluated with scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy before and after close-spaced diode testing. Knee temperatures determined from the close-spaced diode test data were used to evaluate cathode performance. Cathodes with a large (10-11) Os-Ru film texture possessed comparatively low knee temperatures. Furthermore, a low knee temperature correlated with a low effective work function as calculated from the close-spaced diode data. It is proposed that the formation of strong (10-11) texture is responsible for the superior performance of the cathode with a multilayered Os-Ru coating.

  4. The origin of hyperferroelectricity in LiBO3 (B = V, Nb, Ta, Os)

    PubMed Central

    Li, Pengfei; Ren, Xinguo; Guo, Guang-Can; He, Lixin

    2016-01-01

    The electronic and structural properties of LiBO3 (B = V, Nb, Ta, Os) are investigated via first-principles methods. We show that LiBO3 belong to the recently proposed hyperferroelectrics (hyperFEs), i.e., they all have unstable longitudinal optic phonon modes. Especially, the ferroelectric-like instability in the metal LiOsO3, whose optical dielectric constant goes to infinity, is a limiting case of hyperFEs. Via an effective Hamiltonian, we further show that, in contrast to normal proper ferroelectricity, in which the ferroelectric instability usually comes from long-range coulomb interactions, the hyperFE instability is due to the structure instability driven by short-range interactions. This could happen in systems with large ion size mismatches, which therefore provides a useful guidance in searching for novel hyperFEs. PMID:27694996

  5. Permanent magnet synchronous motor servo system control based on μC/OS

    NASA Astrophysics Data System (ADS)

    Shi, Chongyang; Chen, Kele; Chen, Xinglong

    2015-10-01

    When Opto-Electronic Tracking system operates in complex environments, every subsystem must operate efficiently and stably. As a important part of Opto-Electronic Tracking system, the performance of PMSM(Permanent Magnet Synchronous Motor) servo system affects the Opto-Electronic Tracking system's accuracy and speed greatly[1][2]. This paper applied embedded real-time operating system μC/OS to the control of PMSM servo system, implemented SVPWM(Space Vector Pulse Width Modulation) algorithm in PMSM servo system, optimized the stability of PMSM servo system. Pointing on the characteristics of the Opto-Electronic Tracking system, this paper expanded μC/OS with software redundancy processes, remote debugging and upgrading. As a result, the Opto- Electronic Tracking system performs efficiently and stably.

  6. 32 CFR 1630.17 - Class 1-O-S: Conscientious objector to all military service (separated).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Class 1-O-S: Conscientious objector to all... National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.17 Class 1-O-S: Conscientious... (including their reserve components) by reason of conscientious objection to participation in both...

  7. Roles of pollen-specific boron efflux transporter, OsBOR4, in the rice fertilization process.

    PubMed

    Tanaka, Nobuhiro; Uraguchi, Shimpei; Saito, Akihiro; Kajikawa, Masataka; Kasai, Koji; Sato, Yutaka; Nagamura, Yoshiaki; Fujiwara, Toru

    2013-12-01

    Arabidopsis thaliana BOR1 was the first boron (B) transporter identified in living systems. There are four AtBOR1-like genes, OsBOR1, 2, 3 and 4, present in the rice genome. We characterized the activity, expression and physiological function of OsBOR4. OsBOR4 is an active efflux transporter of B. Quantitative PCR analysis and OsBOR4 promoter-green fluorescent protein (GFP) fusion revealed that OsBOR4 was both highly and specifically expressed in pollen. We obtained five Tos17 insertion mutants of osbor4. The pollen grains were viable and development of floral organs was normal in the homozygous osbor4 mutants. We observed that in all Tos17 insertion lines tested, the frequency of osbor4 homozygous plants was lower than expected in the progeny of self-fertilized heterozygous plants. These results establish that OsBOR4 is essential for normal reproductive processes. Pollen from osbor4 homozygous plants elongated fewer tubes on wild-type stigmas, and tube elongation of mutant pollen was less efficient compared with the wild-type pollen, suggesting reduced competence of osbor4 mutant pollen. The reduced competence of mutant pollen was further supported by the crosses of independent Tos17-inserted alleles of OsBOR4. Our results suggest that OsBOR4, a boron efflux transporter, is required for normal pollen germination and/or tube elongation.

  8. The rice (E)-beta-caryophyllene synthase (OsTPS3) accounts for the major inducible volatile sesquiterpenes.

    PubMed

    Cheng, Ai-Xia; Xiang, Cai-Yu; Li, Jian-Xu; Yang, Chang-Qing; Hu, Wen-Li; Wang, Ling-Jian; Lou, Yong-Gen; Chen, Xiao-Ya

    2007-06-01

    Terpenoids serve as both constitutive and inducible defense chemicals in many plant species, and volatile terpenes participate in plant a indirect defense by attracting natural enemies of the herbivores. The rice (Oryza sativa L.) genome contains about 50 genes encoding putative terpene synthases (TPSs). Here we report that two of the rice sesquiterpene synthase genes, OsTPS3 and OsTPS13, encode (E)-beta-caryophyllene synthase and (E,E)-farnesol synthase, respectively. In vitro, the recombinant protein of OsTPS3 catalyzed formation of (E)-beta-caryophyllene and several other sesquiterpenes, including beta-elemene and alpha-humulene, all being components of inducible volatiles of rice plants. The transcript levels of OsTPS3 exhibit a circadian rhythm of fluctuation, and its expression was also greatly induced by methyl jasmonate (MeJA). In addition, expression of OsTPS3 in transgenic plants of Arabidopsis thaliana resulted in emitting high quantities of OsTPS3 products. We also overexpressed OsTPS3 in rice plants which then produced more (E)-beta-caryophyllene after MeJA treatment. Finally, we found that the MeJA-treated transgenic rice plants attracted more parasitoid wasps of Anagrus nilaparvatae than the wild-type. These results demonstrate that OsTPS3, an enzyme catalyzing the formation of volatile sesquiterpenes, plays a role in indirect defense of rice plants.

  9. Osteogenic potential of biosilica on human osteoblast-like (SaOS-2) cells.

    PubMed

    Wiens, Matthias; Wang, Xiaohong; Schlossmacher, Ute; Lieberwirth, Ingo; Glasser, Gunnar; Ushijima, Hiroshi; Schröder, Heinz C; Müller, Werner E G

    2010-12-01

    Biosilica is a natural polymer, synthesized by the poriferan enzyme silicatein from monomeric silicate substrates. Biosilica stimulates mineralizing activity and gene expression of SaOS-2 cells. To study its effect on the formation of hydroxyapatite (HA), SaOS-2 cells were grown on different silicatein/biosilica-modified substrates (bone slices, Ca-P-coated coverslips, glass coverslips). Growth on these substrates induced the formation of HA nodules, organized in longitudinal arrays or spherical spots. Nodules of sizes above 1 μm were composed of irregularly arranged HA prism-like nanorods, formed by aggregates of three to eight SaOS-2 cells. Moreover, growth on silicatein/biosilica-modified substrates elicited increased [(3)H]dT incorporation into DNA, indicative of enhanced cell proliferation. Consequently, an in vitro-based bioassay was established to determine the ratio between [(3)H]dT incorporation and HA formation. This ratio was significantly higher for cells that grew on silicatein/biosilica-modified substrates than for cells on Ca-P-coated coverslips or plain glass slips. Hence, we propose that this ratio of in vitro-determined parameters reflects the osteogenic effect of different substrates on bone-forming cells. Finally, qRT-PCR analyses demonstrated that growth of SaOS-2 cells on a silicatein/biosilica matrix upregulated BMP2 (bone morphogenetic protein 2, inducer of bone formation) expression. In contrast, TRAP (tartrate-resistant acid phosphatase, modulator of bone resorption) expression remained unaffected. We conclude that biosilica shows pronounced osteogenicity in vitro, qualifying this material for studies of bone replacement also in vivo.

  10. Osteoporosis in men: findings from the Osteoporotic Fractures in Men Study (MrOS).

    PubMed

    Cawthon, Peggy M; Shahnazari, Mohammad; Orwoll, Eric S; Lane, Nancy E

    2016-02-01

    The lifespan of men is increasing and this is associated with an increased prevalence of osteoporosis in men. Osteoporosis increases the risk of bone fracture. Fractures are associated with increased disability and mortality, and public health problems. We review here the study of osteoporosis in men as obtained from a longitudinal cohort of community-based older men, the Osteoporotic Fractures in Men Study (MrOS).

  11. Guided ion beam and theoretical studies of the reactions of Re+, Os+, and Ir+ with CO

    NASA Astrophysics Data System (ADS)

    Kim, JungSoo; Cox, Richard M.; Armentrout, P. B.

    2016-11-01

    The kinetic-energy dependences of the reactions M+ + CO where M+ = Re+, Os+, and Ir+ are studied using guided ion-beam tandem mass spectrometry. Formation of both MO+ and MC+ was observed in endothermic processes for all three metals. Modeling of the data provides thresholds that yield 0 K bond dissociation energies (BDEs, in eV) of 4.67 ± 0.09 (Re+-O), 4.82 ± 0.14 (Os+-O), 4.25 ± 0.11 (Ir+-O), 5.13 ± 0.12 (Re+-C), 6.14 ± 0.14 (Os+-C), and 6.58 ± 0.12 (Ir+-C). These BDEs agree well with literature values within experimental uncertainties demonstrating that ground state products are formed for all cases even though some of the reactions are formally spin forbidden. Quantum mechanical calculations at several levels of theory and using several basis sets were performed for MC+ and MO+ (with comparable results taken from the literature in some cases). B3LYP and CCSD(T) calculated ground state BDEs agree reasonably well with experimental values. The ground states in B3LYP and CCSD(T)/CBS calculations are -3Σ (ReC+), 2Δ (OsC+), and +1Σ or 3Δ (IrC+) after including spin-orbit considerations. Relaxed potential energy surfaces (PESs) for the M+ + CO reactions show crossings between surfaces of different spin states such that products can be formed with no barriers in excess of the substantial endothermicities. Unlike results for these metal cations reacting with O2, the kinetic energy dependent cross sections for the formation of MO+ in the M+ + CO reactions exhibit only one feature. Reasons for this differential behavior are discussed in detail.

  12. Polycomb Protein OsFIE2 Affects Plant Height and Grain Yield in Rice

    PubMed Central

    Sheng, Zhonghua; Jiao, Guiai; Tang, Shaoqing; Luo, Ju; Hu, Peisong

    2016-01-01

    Polycomb group (PcG) proteins have been shown to affect growth and development in plants. To further elucidate their role in these processes in rice, we isolated and characterized a rice mutant which exhibits dwarfism, reduced seed setting rate, defective floral organ, and small grains. Map-based cloning revealed that abnormal phenotypes were attributed to a mutation of the Fertilization Independent Endosperm 2 (OsFIE2) protein, which belongs to the PcG protein family. So we named the mutant as osfie2-1. Histological analysis revealed that the number of longitudinal cells in the internodes decreased in osfie2-1, and that lateral cell layer of the internodes was markedly thinner than wild-type. In addition, compared to wild-type, the number of large and small vascular bundles decreased in osfie2-1, as well as cell number and cell size in spikelet hulls. OsFIE2 is expressed in most tissues and the coded protein localizes in both nucleus and cytoplasm. Yeast two-hybrid and bimolecular fluorescence complementation assays demonstrated that OsFIE2 interacts with OsiEZ1 which encodes an enhancer of zeste protein previously identified as a histone methylation enzyme. RNA sequencing-based transcriptome profiling and qRT-PCR analysis revealed that some homeotic genes and genes involved in endosperm starch synthesis, cell division/expansion and hormone synthesis and signaling are differentially expressed between osfie2-1 and wild-type. In addition, the contents of IAA, GA3, ABA, JA and SA in osfie2-1 are significantly different from those in wild-type. Taken together, these results indicate that OsFIE2 plays an important role in the regulation of plant height and grain yield in rice. PMID:27764161

  13. Molecular and biochemical characterization of rice pectin methylesterase inhibitors (OsPMEIs).

    PubMed

    Nguyen, Hong Phuong; Jeong, Ho Young; Kim, Hun; Kim, Young Chang; Lee, Chanhui

    2016-04-01

    Cell wall modifications such as partial degradation and depolymerization by cell wall hydrolases are normal cellular processes and are required for the functionalities of different cell types. Pectin, one of the major cell wall polysaccharides, is predominantly found in primary cell walls and middle lamellae and is subjected to in muro modification, primarily by cell wall-localized pectin methylesterases (PMEs). Molecular biochemical studies have demonstrated that enzymatic activities of PMEs are governed by multiple pectin methylesterase inhibitors (PMEIs), which consequently control the pectin methylesterification status. Although a few studies in Arabidopsis have shown the importance of this PMEI-mediated regulation in the biophysical properties of cell walls, little is known about the molecular physiological functions of rice PMEIs. We found 49 members of the PMEI family in the rice genome. Analysis of their transcript levels by quantitative real-time PCR and meta expression analysis showed that they are regulated spatially and temporally, as well as in response to diverse stresses. Quantification of cell wall-bound methylesters indicated that the degree of pectin methylesterification is developmentally regulated; in particular, higher PMEI activities were detected in cell wall proteins prepared from young leaves. Furthermore, an activity assay demonstrated that two recombinant OsPMEI proteins (OsPMEI8 and 12) were able to inhibit the enzymatic activity of a commercial PME protein. Subcellular localization indicated that OsPMEI8 is targeted to the middle lamella and OsPMEI12 is localized in the plasma membrane and nucleus. Taken together, our findings provide the first molecular and biochemical evidence for functional characterization of PMEIs in rice growth and development.

  14. PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

    SciTech Connect

    Barnett, J. Matthew; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carter, Gregory L.; Douglas, David D.; Carrell, Dorothy M.

    2006-01-25

    This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG&G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables.

  15. Rice Phytochrome B (OsPhyB) Negatively Regulates Dark- and Starvation-Induced Leaf Senescence

    PubMed Central

    Piao, Weilan; Kim, Eun-Young; Han, Su-Hyun; Sakuraba, Yasuhito; Paek, Nam-Chon

    2015-01-01

    Light regulates leaf senescence and light deprivation causes large-scale transcriptional reprogramming to dismantle cellular components and remobilize nutrients to sink organs, such as seeds and storage tissue. We recently reported that in Arabidopsis (Arabidopsis thaliana), Phytochrome-Interacting Factor4 (PIF4) and PIF5 promote dark-induced senescence and natural senescence by directly activating the expression of typical senescence-associated genes (SAGs), including ORESARA1 (ORE1) and ETHYLENE INSENSITIVE3 (EIN3). In contrast, phytochrome B (PhyB) inhibits leaf senescence by repressing PIF4 and PIF5 at the post-translational level. Although we found how red light signaling represses leaf senescence in Arabidopsis, it remains unknown whether PhyB and/or PhyA are involved in leaf senescence in rice (Oryza sativa). Here we show that rice phyB knockout mutants (osphyB-1, -2, and -3) exhibited an early senescence phenotype during dark-induced senescence, but an osphyA knockout mutant (osphyA-3) senesced normally. The RT-qPCR analysis revealed that several senescence-associated genes, including OsORE1 and OsEIN3, were significantly up-regulated in osphyB-2 mutants, indicating that OsPhyB also inhibits leaf senescence, like Arabidopsis PhyB. We also found that leaf segments of osphyB-2 senesced faster even under light conditions. Supplementation with nitrogen compounds, such as KNO3 and NH4NO3, rescued the early senescence phenotype of osphyB-2, indicating that starvation is one of the major signaling factors in the OsPhyB-dependent leaf senescence pathway. PMID:27135344

  16. Optimization techniques for FORTRAN 4 (G and H) programs written for the IBM 360 under OS

    NASA Technical Reports Server (NTRS)

    Dean, J. L.

    1971-01-01

    A fairly complete list is reported of programming techniques which are available to the programmer for optimizing the execution time of production programs written in FORTRAN IV (G and H) for the IBM 360 under OS. After the program has been complied under FORTRAN H, OPT=2, then the process of actually changing code begins. The bulk of execution time of FORTRAN programs can almost always be attributed to a few loops, and primary consideration is given to these.

  17. NQRS Data for C10H11BrOS (Subst. No. 1240)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C10H11BrOS (Subst. No. 1240)

  18. Comment on ''Low-frequency anomaly in /sup 172/Os moment of inertia''

    SciTech Connect

    Pauling, L.

    1988-02-01

    I suggest that the anomaly at I = 6/sup +/ in the ground-state band of /sup 172/Os results from the increase from two to three in the difference in nucleon number of the revolving cluster when I increases to I+2, and that the yrast cusp at I = 16/sup +/ corresponds to the change in structure from one revolving cluster to two revolving clusters. Values of the electric quadrupole moment are predicted.

  19. New insights from old spherules: Os-W isotope and HSE evidence for Paleoarchean meteorite bombardment of the Earth

    NASA Astrophysics Data System (ADS)

    Schulz, T.; Luguet, A. A.; Koeberl, C.

    2014-12-01

    Introduction: Although still debated, spherule beds in the Barberton Mountain Land (~3.4 Ga) are suspected to represent remnants of impact-generated and ballistically emplaced silicate melt droplets [e.g. 1]. Such deposits provide the only window into the late stages of the heavy meteorite bombardment on Earth as their source craters have long since been obliterated. In order to identify a possible meteoritic component and, if successful, to discuss potential projectile materials, we are performing a detailed Os-W isotope as well as HSE abundance study on spherule layers from the recently drilled ICDP BARB5 core (grid location 25°30`50.76``S, 31°33`10.08``E). Samples and Methods: Samples were taken from a spherule-containing meta-sedimentary core section discovered between 510 and 512 m depth. About 100 mg of homogenized sample powders were spiked with a mixed 190Os, 185Re, 191Ir and 194Pt tracer and treated in a high pressure asher using inverse aqua regia, followed by conventional extraction schemes for Os and the other HSEs [4]. Chemical and Os isotope measurements (via N-TIMS) were performed in Vienna, whereas HSE measurements were undertaken via ICP MS in Bonn. Results and Discussion: Our preliminary Os isotope data reveal a trend between samples exhibiting high spherule to matrix ratios (187Os/188Os ~0.106 and Os ~0.4 ppm) and samples with lower ones (187Os/188Os up to ~0.304 and Os ~0.008 ppm). Notably, the most unradiogenic samples exhibit carbonaceous-chondrite-like initial 187Os/188Os and HSE ratios, whereas all other samples are clear non-chondritic. These findings support an extraterrestrial contribution in the spherules and can be interpreted compared to conclusions drawn from a Cr isotope study performed on similar samples [3], possibly representing a different impact event and favouring a chondritic projectile. However, further considerations based on precise Os/W ratio determinations and high-precision 182W isotope data, will be presented at the

  20. Isotope shift of the electric-dipole transition in Os{sup -}

    SciTech Connect

    Kellerbauer, A.; Canali, C.; Fischer, A.; Warring, U.; Fritzsche, S.

    2011-12-15

    The isotope shift of the bound-bound electric dipole transition at 1162.75 nm in the osmium anion was measured by high-precision collinear laser spectroscopy. The transition was observed in all naturally occurring isotopes, including {sup 184}Os{sup -} with a natural abundance of 0.02%. We combined the data with our prior measurements of the hyperfine structure in {sup 187}Os{sup -} and {sup 189}Os{sup -} and used them to determine experimental values for the isotope shift coefficients. The normal mass shift, specific mass shift, and field shift coefficients were found to be M{sub NMS}=141.4 GHz u, M{sub SMS}=2.4(12.6) THz u, and F=16.2(9.9) GHz fm{sup -2}, respectively. Theoretical values for the M{sub SMS} and F parameters were calculated based on a series of relativistic configuration interaction computations and a Fermi-like charge distribution and found to be in good agreement with the experimental values.

  1. Spectroscopy of the neutron-deficient nucleus {sup 167}Os{sub 91}

    SciTech Connect

    O'Donnell, D.; Simpson, J.; Hornillos, M. B. Gomez; Labiche, M.; Grahn, T.; Joss, D. T.; Bianco, L.; Judson, D. S.; Page, R. D.; Paul, E. S.; Petri, M.; Petts, A.; Sapple, P. J.; Thomson, J.; Watkins, H. V.; Scholey, C.; Greenlees, P. T.; Jakobsson, U.; Jones, P.; Julin, R.

    2009-06-15

    Excited states of the nucleus {sup 167}Os have been populated by the reaction {sup 92}Mo({sup 78}Kr,2pn). The JUROGAM {gamma}-ray detector array has been used in conjunction with the RITU gas-filled separator and the GREAT spectrometer to observe prompt {gamma} rays in coincidence with recoiling fusion-evaporation residues and their subsequent decay by {alpha} particle emission. By correlating prompt {gamma} radiation with the characteristic {alpha} radioactivity of {sup 167}Os, it has been possible to extend the level scheme for this nucleus significantly. In particular, an extension of the yrast band and four previously unobserved bands are reported. In addition, the recoil distance Doppler-shift method was used to determine a lifetime of {tau}=20(4) ps for The I{sup {pi}}=17/2{sup +} state in {sup 167}Os. Hence, the level of collectivity and magnitude of deformation of the low spin yrast band of this nucleus is established.

  2. Real-time volume rendering of digital medical images on an iOS device

    NASA Astrophysics Data System (ADS)

    Noon, Christian; Holub, Joseph; Winer, Eliot

    2013-03-01

    Performing high quality 3D visualizations on mobile devices, while tantalizingly close in many areas, is still a quite difficult task. This is especially true for 3D volume rendering of digital medical images. Allowing this would empower medical personnel a powerful tool to diagnose and treat patients and train the next generation of physicians. This research focuses on performing real time volume rendering of digital medical images on iOS devices using custom developed GPU shaders for orthogonal texture slicing. An interactive volume renderer was designed and developed with several new features including dynamic modification of render resolutions, an incremental render loop, a shader-based clipping algorithm to support OpenGL ES 2.0, and an internal backface culling algorithm for properly sorting rendered geometry with alpha blending. The application was developed using several application programming interfaces (APIs) such as OpenSceneGraph (OSG) as the primary graphics renderer coupled with iOS Cocoa Touch for user interaction, and DCMTK for DICOM I/O. The developed application rendered volume datasets over 450 slices up to 50-60 frames per second, depending on the specific model of the iOS device. All rendering is done locally on the device so no Internet connection is required.

  3. Photodisintegration of the isotopes {sup 186,188,189,190,192}Os: Similarities and distinctions

    SciTech Connect

    Varlamov, V. V.; Makarov, M. A.; Peskov, N. N.; Stepanov, M. E.

    2015-09-15

    In addition to the results obtained earlier for the isotopes {sup 188,189}Os, experimental data on the photodisintegration of the isotopes {sup 186,190,192}Os are analyzed on the basis of specially introduced objective criteria of reliability of data on the cross sections for partial photoneutron reactions. It is found that the (γ, 1n), (γ, 2n), and (γ, 3n) cross sections for each isotope satisfy differently or, on the contrary, do not satisfy the data-reliability criteria. In many cases, the multiplicity transition functions specified as the ratios F{sub i} = σ(γ, in)/σ(γ, xn) of the cross sections for the (γ, in) partial reactions to the neutron-yield reaction cross section σ(γ, xn) = σ(γ, 1n) + 2σ(γ, 2n) + 3σ(γ, 3n) +... have values that are physically unreliable by definition. It is shown that ambiguities in the dependence of significant systematic uncertainties in experimentally determined neutron multiplicities on the measured kinetic energies is the reason for this. The dependence of these uncertainties on the energy spectra of neutrons is analyzed. For the isotopes {sup 186,190,192}Os, new evaluated data satisfying the data-reliability criteria are obtained for the cross sections for partial and total photoneutron reactions.

  4. MOLAR: Modular Linux and Adaptive Runtime Support for HEC OS/R Research

    SciTech Connect

    Frank Mueller

    2009-02-05

    MOLAR is a multi-institution research effort that concentrates on adaptive, reliable,and efficient operating and runtime system solutions for ultra-scale high-end scientific computing on the next generation of supercomputers. This research addresses the challenges outlined by the FAST-OS - forum to address scalable technology for runtime and operating systems --- and HECRTF --- high-end computing revitalization task force --- activities by providing a modular Linux and adaptable runtime support for high-end computing operating and runtime systems. The MOLAR research has the following goals to address these issues. (1) Create a modular and configurable Linux system that allows customized changes based on the requirements of the applications, runtime systems, and cluster management software. (2) Build runtime systems that leverage the OS modularity and configurability to improve efficiency, reliability, scalability, ease-of-use, and provide support to legacy and promising programming models. (3) Advance computer reliability, availability and serviceability (RAS) management systems to work cooperatively with the OS/R to identify and preemptively resolve system issues. (4) Explore the use of advanced monitoring and adaptation to improve application performance and predictability of system interruptions. The overall goal of the research conducted at NCSU is to develop scalable algorithms for high-availability without single points of failure and without single points of control.

  5. Synthesis, characterization, in vitro antimicrobial, and U2OS tumoricidal activities of different coumarin derivatives

    PubMed Central

    2013-01-01

    Background Coumarin and its derivatives are biologically very active. It was found that the enhanced activities are dependent on the coumarin nucleus. Biological significance of these compounds include anti-bacterial, anti-thrombotic and vasodilatory, anti-mutagenic, lipoxygenase and cyclooxygenase inhibition, scavenging of reactive oxygen species, and anti-tumourigenic. Our interest in medicinal chemistry of dicoumarol compounds have been developed by keeping in view the importance of coumarins along with its derivatives in medicinal chemistry. All the synthesized compounds were fully characterized by spectroscopic and analytical techniques and were screened for antimicrobial and U2OS bone cancer activities. Results 4-hydroxycoumarin was derivatized by condensing with different aldehydes yielding the dicoumarol and translactonized products. Elemental analyses, ESI(+,−) MS, 1H and 13C{1H}-NMR, infrared spectroscopy and conductance studies were used to characterize the synthesized compounds which revealed the dicoumarol and dichromone structures for the compounds. The compounds were screened against U2OS cancerous cells and pathogenic micro organisms. The compounds with intermolecular H-bonding were found more active revealing a possible relationship among hydrogen bonding, cytotoxicity and antimicrobial activities. Conclusion Coumarin based drugs can be designed for the possible treatment of U2OS leukemia. PMID:23587363

  6. Mapping of decadal middle Adriatic oceanographic variability and its relation to the BiOS regime

    NASA Astrophysics Data System (ADS)

    Mihanović, Hrvoje; Vilibić, Ivica; Dunić, Natalija; Å epić, Jadranka

    2015-08-01

    We analyzed long-term time series of temperature, salinity, and dissolved oxygen (DO) concentrations collected along the Palagruža Sill transect (middle Adriatic) between 1952 and 2010. The data have been mostly collected on seasonal basis, allowing for extraction of seasonal signal from the series. By applying Self-Organizing Maps (SOM) method, a kind of unsupervised neural network method, the processes on a decadal time scale emerged as the most relevant for changes of oceanographic properties in the middle Adriatic area. Sensitivity studies revealed that oceanographic patterns obtained by SOM were not sensitive to shortening of time series, to removal of data from one station or to removal of DO from the analysis. Simultaneous SOM-based mapping of sea surface heights in the northern Ionian Sea, with these heights serving as a proxy for the Adriatic-Ionian Bimodal Oscillating System (BiOS), revealed asymmetry between anticyclonic and cyclonic BiOS patterns and correlated the decadal oscillations in the middle Adriatic with the reversals in the BiOS circulation regimes. These reversals are found to either rapidly change oceanographic properties in the middle Adriatic (e.g., during the Eastern Mediterranean Transient) or to change them with a time lag of 2-3 years. The mapped connections may be used for a short-time (a few years) forecasting of the Adriatic oceanographic properties or for mapping future climate decadal oscillations as seen by ocean climate models.

  7. Oxygen deficit alleviates phosphate overaccumulation toxicity in OsPHR2 overexpression plants.

    PubMed

    Li, Shuai; Wang, Chuang; Zhou, Lian; Shou, Huixia

    2014-05-01

    Overexpression of OsPHR2 increases phosphate (Pi) uptake and causes overaccumulation of Pi in rice plants, which is toxic to rice plants when they are grown in media with a sufficient Pi supply. The toxicity that results from OsPHR2 overexpression can be significantly relieved by growing the plants in a waterlogged paddy field. A comparison of the Pi uptake and growth status of OsPHR2-overexpression plants (PHR2-Oe plants) grown in paddy fields or in a laboratory setting in aerated or stagnant hydroponic conditions indicated that the oxygen limitation that is present in paddy fields and in stagnant rice culture solutions inhibits the Pi overaccumulation toxicity of PHR2-Oe plants by reducing their Pi uptake. Quantitative RT-PCR demonstrated that the expression of Pi-starvation-induced (PSI) genes was induced by oxygen limitation in both wild-type and PHR2-Oe plants. The induction of PSI genes is the consequence of reducing the Pi concentration in stagnant plants. Thus, when evaluating the efficiency of Pi use in rice germplasm or transgenic materials under hydroponic conditions, the impact of the low oxygen condition that exists in waterlogged paddies should be considered.

  8. Inactivation of the WNT5A Alternative Promoter B Is Associated with DNA Methylation and Histone Modification in Osteosarcoma Cell Lines U2OS and SaOS-2.

    PubMed

    Vaidya, Himani; Rumph, Candie; Katula, Karen S

    2016-01-01

    WNT5A is a secreted ligand involved in Wnt pathway signaling and has a role in cell movement and differentiation. Altered WNT5A expression is associated with various cancers, although in most studies the focus has been on only one of the known WNT5A isoforms. In this study, we analyzed expression from two of the major WNT5A promoters, termed promoter A and promoter B, in normal human osteoblasts, SaOS-2 and U2OS osteosarcoma cell lines, and osteosarcoma tumor tissue. We found that both promoters A and B are active in normal osteoblasts with nearly 11-fold more promoter B than A transcripts. Promoter B but not promoter A transcripts are decreased or nearly undetectable in the SaOS-2 and U2OS cell lines and osteosarcoma tumor tissues. Transient transfection of promoter A and promoter B reporter constructs confirmed that SaOS-2 cells have the necessary factors to transcribe both promoters. Bisulfite sequencing analysis revealed that three CpG enriched regions upstream of the promoter B exon 1βare highly methylated in both SaOS-2 and U2OS cells. The CpG island sub-region R6 located in promoter B exon 1β was approximately 51% methylated in SaOS-2 and 25% methylated in U2OS. Region 3 was approximately 28% methylated in normal osteoblasts, whereas the others were unmethylated. Promoter B was re-activated by treatment of SaOS-2 cells with 1 μM 5-azacytidine, which was associated with only a small insignificant change in methylation of sub-region R6. ChIP analysis of U2OS and SaOS-2 cells indicated that the promoter B region is less enriched in the active histone mark H3K4me3, in comparison to promoter A and that there is increased enrichment of the repressive mark H3K27me3 in association with the promoter B genomic region in the cell line SaOS-2. These findings show that epigenetic inactivation of the WNT5A promoter B involves both DNA methylation and histone modifications and suggest that differential expression of the WNT5A alternative promoters A and B is a

  9. High-pressure synthesis, crystal structures, and magnetic properties of 5d double-perovskite oxides Ca2MgOsO6 and Sr2MgOsO6.

    PubMed

    Yuan, Yahua; Feng, Hai L; Ghimire, Madhav Prasad; Matsushita, Yoshitaka; Tsujimoto, Yoshihiro; He, Jianfeng; Tanaka, Masahiko; Katsuya, Yoshio; Yamaura, Kazunari

    2015-04-06

    Double-perovskite oxides Ca2MgOsO6 and Sr2MgOsO6 have been synthesized under high-pressure and high-temperature conditions (6 GPa and 1500 °C). Their crystal structures and magnetic properties were studied by a synchrotron X-ray diffraction experiment and by magnetic susceptibility, specific heat, isothermal magnetization, and electrical resistivity measurements. Ca2MgOsO6 and Sr2MgOsO6 crystallized in monoclinic (P21/n) and tetragonal (I4/m) double-perovskite structures, respectively; the degree of order of the Os and Mg arrangement was 96% or higher. Although Ca2MgOsO6 and Sr2MgOsO6 are isoelectric, a magnetic-glass transition was observed for Ca2MgOsO6 at 19 K, while Sr2MgOsO6 showed an antiferromagnetic transition at 110 K. The antiferromagnetic-transition temperature is the highest in the family. A first-principles density functional approach revealed that Ca2MgOsO6 and Sr2MgOsO6 are likely to be antiferromagnetic Mott insulators in which the band gaps open, with Coulomb correlations of ∼1.8-3.0 eV. These compounds offer a better opportunity for the clarification of the basis of 5d magnetic sublattices, with regard to the possible use of perovskite-related oxides in multifunctional devices. The double-perovskite oxides Ca2MgOsO6 and Sr2MgOsO6 are likely to be Mott insulators with a magnetic-glass (MG) transition at ∼19 K and an antiferromagnetic (AFM) transition at ∼110 K, respectively. This AFM transition temperature is the highest among double-perovskite oxides containing single magnetic sublattices. Thus, these compounds offer valuable opportunities for studying the magnetic nature of 5d perovskite-related oxides, with regard to their possible use in multifunctional devices.

  10. Osmium Atoms and Os2 Molecules Move Faster on Selenium-Doped Compared to Sulfur-Doped Boronic Graphenic Surfaces.

    PubMed

    Barry, Nicolas P E; Pitto-Barry, Anaïs; Tran, Johanna; Spencer, Simon E F; Johansen, Adam M; Sanchez, Ana M; Dove, Andrew P; O'Reilly, Rachel K; Deeth, Robert J; Beanland, Richard; Sadler, Peter J

    2015-07-28

    We deposited Os atoms on S- and Se-doped boronic graphenic surfaces by electron bombardment of micelles containing 16e complexes [Os(p-cymene)(1,2-dicarba-closo-dodecarborane-1,2-diselenate/dithiolate)] encapsulated in a triblock copolymer. The surfaces were characterized by energy-dispersive X-ray (EDX) analysis and electron energy loss spectroscopy of energy filtered TEM (EFTEM). Os atoms moved ca. 26× faster on the B/Se surface compared to the B/S surface (233 ± 34 pm·s(-1) versus 8.9 ± 1.9 pm·s(-1)). Os atoms formed dimers with an average Os-Os distance of 0.284 ± 0.077 nm on the B/Se surface and 0.243 ± 0.059 nm on B/S, close to that in metallic Os. The Os2 molecules moved 0.83× and 0.65× more slowly than single Os atoms on B/S and B/Se surfaces, respectively, and again markedly faster (ca. 20×) on the B/Se surface (151 ± 45 pm·s(-1) versus 7.4 ± 2.8 pm·s(-1)). Os atom motion did not follow Brownian motion and appears to involve anchoring sites, probably S and Se atoms. The ability to control the atomic motion of metal atoms and molecules on surfaces has potential for exploitation in nanodevices of the future.

  11. Control of tiller growth of rice by OsSPL14 and Strigolactones, which work in two independent pathways.

    PubMed

    Luo, Le; Li, Weiqiang; Miura, Kotaro; Ashikari, Motoyuki; Kyozuka, Junko

    2012-10-01

    The architecture of rice is greatly influenced by the growth of tillers, i.e. vegetative shoot branches. OsSPL14, a member of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes, and strigolactones (SLs) are known to suppress outgrowth of tiller buds. OsSPL14 also regulates panicle development. We show that OsSPL14 mRNA accumulates in leaf primordia during the vegetative phase and in the primordia of bracts, or modified leaves, in the panicles, but not in the meristems. OsSPL14 is a target of miR156, and accumulation of OsSPL14 transcripts is negatively regulated by miR156. The enhancement of the expression level of OsSPL14 by the introduction of the mOsSPL14 gene, in which the miR156 cleavage site is mutated, resulted in an increase in the plastochron, an acceleration of flowering and a decrease in tiller number in the wild type and in dwarf10-2, an SL-deficient mutant. Our analysis suggests that OsSPL14 and SLs function in parallel pathways to suppress tiller growth. SLs exuded from roots trigger germination of root parasitic plants that can cause severe damage to crop productivity. SL-deficient mutants, however, exhibit an excess branching phenotype which is usually undesirable for productivity. Our results indicate that OsSPL14 can be used to manipulate the branching patterns of SL-deficient mutants. We also confirmed that this strategy is applicable to Arabidopsis. A greater understanding of the OsSPL14 and SL pathways and their interactions may help in the production of root parasite-resistant crops.

  12. Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

    NASA Astrophysics Data System (ADS)

    Rooney, Alan D.; Selby, David; Lewan, Michael D.; Lillis, Paul G.; Houzay, Jean-Pierre

    2012-01-01

    Successful application of the 187Re-187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re-Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC = 17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC = 2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72 h at 250, 300, 325 and 350 °C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re-Os isotopic and elemental abundance. The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides. Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re-Os systematics in ORS as supported by various studies on natural systems. The elemental

  13. Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

    USGS Publications Warehouse

    Rooney, A.D.; Selby, D.; Lewan, M.D.; Lillis, P.G.; Houzay, J.-P.

    2012-01-01

    Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re–Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC = 17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC = 2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72 h at 250, 300, 325 and 350 °C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re–Os isotopic and elemental abundance. The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides. Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re–Os systematics in ORS as supported by various studies on natural systems. The

  14. 187Re- 187Os Nuclear Geochronometry: Dating Peridotitic Diamond Sulphide Inclusions

    NASA Astrophysics Data System (ADS)

    Roller, Goetz

    2015-04-01

    Nuclear geochronometry [1-2] is a new dating method which combines principles of geochronology with nuclear astrophysics. It is embedded in other scientific fields like cosmochemistry, cosmology and nuclear theory, which pose tight constraints for nuclear geochronometry. It is based upon identified Re/Os element ratios ˜ 1, interpreted as the nuclear production ratio, and ultra-subchondritic initial 187Os/188Os ratios within terrestrial rocks, suggesting that Earth's core still contains element ratios and isotopic signatures of at least two rapid (r) neutron-capture process [3] events. The 13.78 Ga old component, represented by the isotopic signature of a komatiitic basalt [5085 BasKom] [4] from the Barberton Greenstone Belt (Onverwacht Group, South Africa), is assigned to the Earth's inner core. The other isotopic signatures identified so far within pyroxenites / komatiites are assigned to its outer core due to at least one gravitational collapse of the old component, commencing ˜ 3.48 Ga [2] and resulting in one or more additional r-process event(s). Here I show that 187Re-187Os nuclear geochronometry can also be successfully applied for dating peridotitic diamond sulphide inclusions by means of two-point-isochrones (TPI), using a so-called nuclear geochronometer always as the second data point in a TPI diagram. It turns out that the method may have a huge potential to constrain the chemical evolution of the SCLM. For example, TPI ages for Ellendale (Australia) peridotitic diamond sulphide inclusions EL50, EL23, EL54-1, EL54-3, EL55-1 and EL65 reported in the literature [5] reveal at least two main fractionation events. The age cluster between 1.4 Ga and 1.5 Ga is consistent with a previously reported isochrone age [5]. The event ˜ 2.3 ± 0.3 Ga overlaps the Great Oxidation Event (GOE) between 2.22 Ga and 2.46 Ga. While the ˜ 1.4 Ga to 1.5 Ga events lead to fractionation of the 187Re/188Os ratios towards values typical for mantle peridotite, the latter caused

  15. The DnaJ OsDjA7/8 is essential for chloroplast development in rice (Oryza sativa).

    PubMed

    Zhu, Xiaobo; Liang, Sihui; Yin, Junjie; Yuan, Can; Wang, Jing; Li, Weitao; He, Min; Wang, Jichun; Chen, Weilan; Ma, Bingtian; Wang, Yuping; Qin, Peng; Li, Shigui; Chen, Xuewei

    2015-12-10

    DnaJ proteins belong to chaperones of Hsp40 family that ubiquitously participate in various cellular processes. Previous studies have shown chloroplast-targeted DnaJs are involved in the development of chloroplast in some plant species. However, little is known about the function of DnaJs in rice, one of the main staple crops. In this study, we characterized a type I DnaJ protein OsDjA7/8. We found that the gene OsDjA7/8 was expressed in all collected tissues, with a priority in the vigorous growth leaf. Subcellular localization revealed that the protein OsDjA7/8 was mainly distributed in chloroplast. Reduced expression of OsDjA7/8 in rice led to albino lethal at the seedling stage. Transmission electron microscopy observation showed that the chloroplast structures were abnormally developed in the plants silenced for OsDjA7/8. In addition, the transcriptional expression of the genes tightly associated with the development of chloroplast was deeply reduced in the plants silenced for OsDjA7/8. Collectively, our study reveals that OsDjA7/8 encodes a chloroplast-localized protein and is essential for chloroplast development and differentiation in rice.

  16. The rice gene OsZFP6 functions in multiple stress tolerance responses in yeast and Arabidopsis.

    PubMed

    Guan, Qing-jie; Wang, Li-feng; Bu, Qing-yun; Wang, Zhen-yu

    2014-09-01

    The role of zinc finger proteins in organismal stress conditions has been widely reported. However, little is known concerning the function of CCHC-type zinc finger proteins in rice. In this study, OsZFP6, a rice CCHC-type zinc finger protein 6 gene, was cloned from rice using RT-PCR. The OsZFP6 protein contains 305 amino acids and a conserved zinc finger domain and is localised to the nucleus. Southern blot analysis revealed that a single copy was encoded in the rice genome. OsZFP6 expression was increased by abiotic stress, including salt (NaCl), alkali (NaHCO3) and H2O2 treatment. When OsZFP6 was transformed into yeast, the transgenic yeast showed significantly increased resistance to NaHCO3 compared to the control. Moreover, Arabidopsis transgenic plants overexpressing OsZFP6 were more tolerant to both NaHCO3 and H2O2 treatments. Overall, we uncovered a role for OsZFP6 in abiotic stress responses and identified OsZFP6 as a putatively useful gene for developing crops with increased alkali and H2O2 tolerance.

  17. OsWRKY22, a monocot WRKY gene, plays a role in the resistance response to blast.

    PubMed

    Abbruscato, Pamela; Nepusz, Tamás; Mizzi, Luca; Del Corvo, Marcello; Morandini, Piero; Fumasoni, Irene; Michel, Corinne; Paccanaro, Alberto; Guiderdoni, Emmanuel; Schaffrath, Ulrich; Morel, Jean-Benoît; Piffanelli, Pietro; Faivre-Rampant, Odile

    2012-10-01

    With the aim of identifying novel regulators of host and nonhost resistance to fungi in rice, we carried out a systematic mutant screen of mutagenized lines. Two mutant wrky22 knockout lines revealed clear-cut enhanced susceptibility to both virulent and avirulent Magnaporthe oryzae strains and altered cellular responses to nonhost Magnaporthe grisea and Blumeria graminis fungi. In addition, the analysis of the pathogen responses of 24 overexpressor OsWRKY22 lines revealed enhanced resistance phenotypes on infection with virulent M. oryzae strain, confirming that OsWRKY22 is involved in rice resistance to blast. Bioinformatic analyses determined that the OsWRKY22 gene belongs to a well-defined cluster of monocot-specific WRKYs. The co-regulatory analysis revealed no significant co-regulation of OsWRKY22 with a representative panel of OsWRKYs, supporting its unique role in a series of transcriptional responses. In contrast, inquiring a subset of biotic stress-related Affymetrix data, a large number of resistance and defence-related genes were found to be putatively co-expressed with OsWRKY22. Taken together, all gathered experimental evidence places the monocot-specific OsWRKY22 gene at the convergence point of signal transduction circuits in response to both host and nonhost fungi encountering rice plants.

  18. Characterization of a purine permease family gene OsPUP7 involved in growth and development control in rice.

    PubMed

    Qi, Zhuyun; Xiong, Lizhong

    2013-11-01

    In this study, PUP-type cytokinin transporter genes were identified in rice (Oryza sativa L.). The Oryza sativa purine permease (OsPUP) family has 12 members that show similar predicted protein sequences with AtPUPs. To reveal the functions of OsPUP genes, we searched the T-DNA mutant library of rice and found one mutant for the member OsPUP7. The T-DNA insertion caused a new transcript that encodes a protein with 26 amino acids different from the native OsPUP7 at the C-terminus. The mutant showed multiple phenotypic changes including increased plant height, big seeds, and delayed flowering. The mutant also showed increased sensitivity to drought and salt stresses and treatments with kinetin and abscisic acid. OsPUP7 is expressed mainly in the vascular bundle, pistil, and stamens. The measurement of cytokinins (CKs) showed that CK content in the mutant spikelets accumulated higher than that in the wild type. Moreover, uptake experiment in the yeast fcy2 mutant suggested that OsPUP7 has the ability to transport caffeine, a CK derivative. Our results indicate that the PUP transport system also exists in rice, and OsPUP7 has an important role in the transport of CK, thus affecting developmental process and stress responses.

  19. RhoA/ROCK pathway inhibition by fasudil suppresses the vasculogenic mimicry of U2OS osteosarcoma cells in vitro.

    PubMed

    Xia, Yun; Cai, Xianyi; Fan, Jiquan; Zhang, Liling; Li, Zhenyu; Ren, Jinghua; Wu, Gang; Zhu, Fang

    2017-02-20

    GTPase RhoA and its downstream Rho-associated coiled-coil-containing protein kinases (ROCKs) are frequently overexpressed in human cancers. Inhibition of the RhoA/ROCK pathway blocks angiogenesis mediated by the vascular endothelial growth factor, which led us to investigate the role of this pathway in vasculogenic mimicry (VM) - a process by which aggressive cancer cells form vessel-like structures that provide adequate blood supply for tumor growth. We showed that the expression of RhoA and its effector kinases ROCK1/2 was much higher in human osteosarcoma (OS) tissues and the human OS cell line U2OS than in nontumorous tissues and cell line hFOB 1.19 using western blot analysis and real-time PCR. Inhibition of the RhoA/ROCK signaling pathway by the pharmacological inhibitor fasudil reduced vascular-like channels of U2OS cells in Matrigel. Furthermore, we used rhodamine-phalloidin immunofluorescence, wound healing assay, and transwell migration assay to examine the effect of fasudil on tumor cell plasticity and motility, both of which play key roles in VM formation. Finally, we explored the underlying mechanisms of fasudil-induced VM destruction. In this context, we showed that the RhoA/ROCK signaling pathway is a novel regulator in VM of U2OS OS cells and suggest that fasudil in conjunction with established treatments may present a novel therapeutic strategy for OS.

  20. OsRRMh, a Spen-like gene, plays an important role during the vegetative to reproductive transition in rice.

    PubMed

    Liu, Derui; Cai, Xiuling

    2013-09-01

    OsRRMh, a homologue of OsRRM, encodes a Spen-like protein, and is composed of two N-terminal RNA recognition motifs (RRM) and one C-terminal Spen paralogue and an orthologue C-terminal domain (SPOC). The gene has been found to be constitutively expressed in the root, stem, leaf, spikelet, and immature seed, and alternative splicing patterns were confirmed in different tissues, which may indicate diverse functions for OsRRMh. The OsRRMh dsRNAi lines exhibited late-flowering and a larger panicle phenotype. When full-length OsRRMh and/or its SPOC domain were overexpressed, the fertility rate and number of spikelets per panicle were both markedly reduced. Also, overexpression of OsRRMh in the Arabidopsis fpa mutant did not restore the normal flowering time, and it delayed flowering in Col plants. Therefore, we propose that OsRRMh may confer one of its functions in the vegetative-to-reproductive transition in rice (Oryza sativa L. subsp. japonica cv. Zhonghua No. 11 (ZH11)).

  1. Retrotransposon-Mediated Aluminum Tolerance through Enhanced Expression of the Citrate Transporter OsFRDL41[OPEN

    PubMed Central

    Yamaji, Naoki; Fujii-Kashino, Miho

    2016-01-01

    High aluminum (Al) tolerance of rice (Oryza sativa) is controlled by multiple tolerance genes, but the regulatory mechanisms underlying the differential expression of these genes are poorly understood. Here, we investigated the factors regulating the expression of OsFRDL4, a gene encoding a citrate efflux transporter involved in Al-induced citrate secretion from the roots. Analysis with chromosome segment substitution lines derived from cv Nipponbare (high OsFRDL4 expression) and cv Kasalath (low OsFRDL4 expression) revealed that the differential expression of OsFRDL4 is responsible for the quantitative trait locus for Al tolerance detected previously on chromosome 1. Comparison of the OsFRDL4 gene structure in cv Nipponbare and cv Kasalath showed that there was no difference in the position of the transcriptional start site, but a 1.2-kb insertion showing high similarity to the solo long terminal repeat of the retrotransposon was found in the promoter region of OsFRDL4 in cv Nipponbare. This insertion showed higher promoter activity and contained nine cis-acting elements for ALUMINUM RESISTANCE TRANSCRIPTION FACTOR1 (ART1). However, this insertion did not alter the spatial expression or cellular localization of OsFRDL4. Furthermore, this insertion was found in most japonica varieties but was largely absent from indica varieties or wild rice species. These results indicate that the 1.2-kb insertion in the OsFRDL4 promoter region in japonica subspecies is responsible for their higher expression level of OsFRDL4 due to the increased number of cis-acting elements of ART1. Our results also suggest that this insertion event happened at the initial stage of domestication of japonica subspecies. PMID:27744299

  2. Physical properties of double perovskite-type barium neodymium osmate Ba{sub 2}NdOsO{sub 6}

    SciTech Connect

    Wakeshima, Makoto; Hinatsu, Yukio; Ohoyama, Kenji

    2013-01-15

    The crystal, magnetic structures and physical properties of the double perovskite-type barium neodymium osmate Ba{sub 2}NdOsO{sub 6} are investigated through powder X-ray and neutron diffraction, electrical conductivity, magnetic susceptibility, and specific heat measurements. The Rietveld analysis reveals that the Nd and Os ions are arranged with regularity over the six-coordinate B sites in a distorted perovskite ABO{sub 3} framework. The monoclinic crystal structure described by space group P2{sub 1}/n (tilt system a{sup -}a{sup -}c{sup +}) becomes more distorted with decreasing temperature from 300 K down to 2.5 K. This compound shows a long-range antiferromagnetic ordering of Os{sup 5+} below 65 K. An antiferromagnetic ordering of Nd{sup 3+} also occurs at lower temperatures ({approx}20 K). The magnetic structure is of Type I and the magnetic moments of Nd{sup 3+} and Os{sup 5+} ions are in the same direction in the ab-plane. - Graphical Abstract: The Magnetic structure of Ba{sub 2}NdOsO{sub 6} is of Type I, and the magnetic moments of the Nd{sup 3+} and Os{sup 5+} ions are in the same direction in the ab-plane. Highlights: Black-Right-Pointing-Pointer Crystal structures of Ba{sub 2}NdOsO{sub 6} are determined to be monoclinic below 300 K. Black-Right-Pointing-Pointer Its electrical resistivity shows a Mott variable-range hopping behavior with localized carriers. Black-Right-Pointing-Pointer An antiferromagnetic ordering of the Os{sup 5+}moment occurs at 65 K. Black-Right-Pointing-Pointer The magnetic structure of Ba{sub 2}NdOsO{sub 6} is determined to be of Type I.

  3. Enhancement of dopamine sensing by layer-by-layer assembly of PVI-dmeOs and Nafion on carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Cui, Hui-Fang; Cui, Yu-Han; Sun, Yu-Long; Zhang, Kuan; Zhang, Wei-De

    2010-05-01

    In this study, carbon nanotubes (CNTs) were modified to further improve their performance in electrochemical sensing of dopamine (DA) levels. After a redox polymer, poly(vinylimidazole) complexed with Os(4, 4'-dimethyl- 2, 2-bipyridine)2Cl (termed PVI-dmeOs) was electrodeposited on multi-wall CNTs (MWCNTs), Nafion and PVI-dmeOs films were successfully layer-by-layer (LBL) assembled on the hydrophilic surface of the as-prepared PVI-dmeOs/CNTs nanocomposites through electrostatic interactions. The LBL assembly was proved by scanning electron microscopy (SEM), electrochemistry and UV-vis spectroscopy measurements. LBL assembly of Nafion/PVI-dmeOs films on CNTs significantly enhanced their linear sweep voltammetry (LSV) response sensitivity to DA, with a maximum enhancement for three Nafion/PVI-dmeOs film-modified MWCNTs. The LSV peak current density of (Nafion/PV I-dmeOs)3/CNT electrodes in response to 10 and 50 µM DA solutions was about 7.3 and 3.9 times those for bare CNTs. At the (Nafion/PV I-dmeOs)3/CNT electrodes, the limit of detection (LOD) (signal-to-noise ratio: 3) was 0.05 µM DA, the linear range was 0.1-10 µM DA (with a linear regression coefficient of 0.97) and the DA-sensing sensitivity was 8.15 µA cm - 2 µM - 1. The newly fabricated (Nafion/PV I-dmeOs)3/CNT electrodes may be developed as an ideal biosensor for direct and in situ measurement of DA levels.

  4. Enhancement of dopamine sensing by layer-by-layer assembly of PVI-dmeOs and Nafion on carbon nanotubes.

    PubMed

    Cui, Hui-Fang; Cui, Yu-Han; Sun, Yu-Long; Zhang, Kuan; Zhang, Wei-De

    2010-05-28

    In this study, carbon nanotubes (CNTs) were modified to further improve their performance in electrochemical sensing of dopamine (DA) levels. After a redox polymer, poly(vinylimidazole) complexed with Os(4, 4'-dimethyl- 2, 2-bipyridine)(2)Cl (termed PVI-dmeOs) was electrodeposited on multi-wall CNTs (MWCNTs), Nafion and PVI-dmeOs films were successfully layer-by-layer (LBL) assembled on the hydrophilic surface of the as-prepared PVI-dmeOs/CNTs nanocomposites through electrostatic interactions. The LBL assembly was proved by scanning electron microscopy (SEM), electrochemistry and UV-vis spectroscopy measurements. LBL assembly of Nafion/PVI-dmeOs films on CNTs significantly enhanced their linear sweep voltammetry (LSV) response sensitivity to DA, with a maximum enhancement for three Nafion/PVI-dmeOs film-modified MWCNTs. The LSV peak current density of (Nafion/PV I-dmeOs)(3)/CNT electrodes in response to 10 and 50 microM DA solutions was about 7.3 and 3.9 times those for bare CNTs. At the (Nafion/PV I-dmeOs)(3)/CNT electrodes, the limit of detection (LOD) (signal-to-noise ratio: 3) was 0.05 microM DA, the linear range was 0.1-10 microM DA (with a linear regression coefficient of 0.97) and the DA-sensing sensitivity was 8.15 microA cm( - 2) microM( - 1). The newly fabricated (Nafion/PV I-dmeOs)(3)/CNT electrodes may be developed as an ideal biosensor for direct and in situ measurement of DA levels.

  5. Functional characterization of a rice de novo DNA methyltransferase, OsDRM2, expressed in Escherichia coli and yeast

    SciTech Connect

    Pang, Jinsong; Dong, Mingyue; Li, Ning; Zhao, Yanli; Liu, Bao

    2013-03-01

    Highlights: ► A rice de novo DNA methyltransferase OsDRM2 was cloned. ► In vitro methylation activity of OsDRM2 was characterized with Escherichia coli. ► Assays of OsDRM2 in vivo methylation were done with Saccharomyces cerevisiae. ► OsDRM2 methylation activity is not preferential to any type of cytosine context. ► The activity of OsDRM2 is independent of RdDM pathway. - Abstract: DNA methylation of cytosine nucleotides is an important epigenetic modification that occurs in most eukaryotic organisms and is established and maintained by various DNA methyltransferases together with their co-factors. There are two major categories of DNA methyltransferases: de novo and maintenance. Here, we report the isolation and functional characterization of a de novo methyltransferase, named OsDRM2, from rice (Oryza sativa L.). The full-length coding region of OsDRM2 was cloned and transformed into Escherichia coli and Saccharomyces cerevisiae. Both of these organisms expressed the OsDRM2 protein, which exhibited stochastic de novo methylation activity in vitro at CG, CHG, and CHH di- and tri-nucleotide patterns. Two lines of evidence demonstrated the de novo activity of OsDRM2: (1) a 5′-CCGG-3′ containing DNA fragment that had been pre-treated with OsDRM2 protein expressed in E. coli was protected from digestion by the CG-methylation-sensitive isoschizomer HpaII; (2) methylation-sensitive amplified polymorphism (MSAP) analysis of S. cerevisiae genomic DNA from transformants that had been introduced with OsDRM2 revealed CG and CHG methylation levels of 3.92–9.12%, and 2.88–6.93%, respectively, whereas the mock control S. cerevisiae DNA did not exhibit cytosine methylation. These results were further supported by bisulfite sequencing of the 18S rRNA and EAF5 genes of the transformed S. cerevisiae, which exhibited different DNA methylation patterns, which were observed in the genomic DNA. Our findings establish that OsDRM2 is an active de novo DNA

  6. Os Isotopic Composition and Highly Siderophile Elements: Tracers of Mantle Melting and Melt Percolation Processes (Voykar Complex, Polar Ural Ophiolites)

    NASA Astrophysics Data System (ADS)

    Batanova, V.; Bruegmann, G.; Savelieva, G.

    2006-12-01

    The Voykar complex is located in the Northern part of the Uralian ophiolite belt and represents Early Devonian lithosphere formed in a suprasubduction environment (e. g. (1)). It is unique in that the mantle peridotites are very well preserved and virtually free of serpentine, and it provides excellent exposures. The mantle section of Voykar complex is composed of harzburgite which is intruded by numerous dunite and pyroxenite channels and contains chromitite ore deposits. The distribution of highly siderophile elements (HSE) in harzburgite and dunite channels can be explained by melt-peridotite reaction processes. The harzburgites (Cr/(Cr+Al) of cr-spinel = 0.3-0.4) show two types of HSE patterns. One is depleted in Pd, Pt and Re relatively to Os, Ir, Ru with (Pt/Ir)N=0.3, the second pattern is flat with (Pt/Ir)N=0.9. The first type of harzburgite has lower ratios of 187Os/188Os (0.1149) compared to the second (0.1236). Dunite and associated orthopyroxenite are significantly enriched in 187Os (187Os/188Os=0.1279 - 0.1327), hence shifted towards lava compositions. Their HSE patterns also show the influence of mantle melts, because they are enriched in Pd ((Pt/Ir)N=5-6). The clinopyroxenite has the highest ratio of 187Os/188Os up to 32.38 and shows even stronger depletion of Os, Ir, Ru relative to Pt, Pd, Re ((Pt/Ir)N=20). They could represent crystallization products of percolating melts. Chromitites have variable 187Os/188Os=0.1244-0.1352, and their HSE concentrations overlap with the range observed in chromitites world-wide. Osmium isotope data show evidence for at least two significant events in the magmatic history of the Voykar ophiolite mantle section: an ancient (2.1-1.9 Ga) melting event formed the depleted spinel harzburgite; a younger melt percolation event (0.6-0.5 Ga) led to the formation of pyroxenite veins, dunite channels and chromitites. The age of melt percolation events based on Os isotopic data coincides with the U-Pb age of zircons found in

  7. A gallery of oil components, their metals and Re-Os signatures

    NASA Astrophysics Data System (ADS)

    Stein, Holly J.; Hannah, Judith L.

    2016-04-01

    Most sediment-hosted metallic ore deposits are one degree of freedom from hydrocarbon. That is, sulfide fluid inclusions may contain vestiges of travel in tandem with hydrocarbon-bearing fluids. For metallic ore deposits of stated metamorphic and magmatic origin, the degrees of freedom are several times more or, in some cases, no relationship exists. Still, the fetish for stereotyping and classifying ore types into hardline ore deposit models (or hybrid models when the data are wildly uncooperative) impedes our ability to move toward a better understanding of source rock. Fluids in the deeper earth, fluids in the crust, and the extraterrestrial rain of metals provide the Re-Os template for oil. So, too, this combination ultimately drives the composition of many metallic ore deposits. The world of crude oil and its complex history of maturation, migration, mixing, metal-rich asphaltene precipitation, and subsequent mobility of lighter and metal-poor components, is an untapped resource for students of ore geology. In the same way that Mississippi Valley-type lead and zinc deposits are described as the outcome of two converging and mixing fluids (metal-bearing and sulfur-bearing fluids), asphaltene precipitation can be an outcome of a lighter oil meeting and mixing with a heavier one. In the petroleum industry, this can spell economic disaster if the pore-space becomes clogged with a non-producible heavy oil or solid bitumen. In ore geology, sulfide precipitation on loss of permeability may create a Pb-Zn deposit. Petroleum systems provide a gallery of successive time-integrated Re-Os results. Heavy or biodegraded oils, if intersected by lighter oil or gas, can generate asphaltite or tar mats, and release a reservoir of still lighter oil (or gas). During this process there are opportunities for separation of metal-enriched aqueous fluids that may retain an imprint of their earlier hydrocarbon history, ultimately trapped in fluid inclusions. Salinity, temperature and p

  8. Different atmospheric moisture divergence responses to extreme and moderate El Niños

    NASA Astrophysics Data System (ADS)

    Xu, Guangzhi; Osborn, Timothy J.; Matthews, Adrian J.; Joshi, Manoj M.

    2016-07-01

    On seasonal and inter-annual time scales, vertically integrated moisture divergence provides a useful measure of the tropical atmospheric hydrological cycle. It reflects the combined dynamical and thermodynamical effects, and is not subject to the limitations that afflict observations of evaporation minus precipitation. An empirical orthogonal function (EOF) analysis of the tropical Pacific moisture divergence fields calculated from the ERA-Interim reanalysis reveals the dominant effects of the El Niño-Southern Oscillation (ENSO) on inter-annual time scales. Two EOFs are necessary to capture the ENSO signature, and regression relationships between their Principal Components and indices of equatorial Pacific sea surface temperature (SST) demonstrate that the transition from strong La Niña through to extreme El Niño events is not a linear one. The largest deviation from linearity is for the strongest El Niños, and we interpret that this arises at least partly because the EOF analysis cannot easily separate different patterns of responses that are not orthogonal to each other. To overcome the orthogonality constraints, a self-organizing map (SOM) analysis of the same moisture divergence fields was performed. The SOM analysis captures the range of responses to ENSO, including the distinction between the moderate and strong El Niños identified by the EOF analysis. The work demonstrates the potential for the application of SOM to large scale climatic analysis, by virtue of its easier interpretation, relaxation of orthogonality constraints and its versatility for serving as an alternative classification method. Both the EOF and SOM analyses suggest a classification of "moderate" and "extreme" El Niños by their differences in the magnitudes of the hydrological cycle responses, spatial patterns and evolutionary paths. Classification from the moisture divergence point of view shows consistency with results based on other physical variables such as SST.

  9. The superficial characterization of a large sample of asteroids: the S3OS2

    NASA Astrophysics Data System (ADS)

    Lazzaro, D.; Angeli, C. A.; Mothe-Diniz, T.; Carvano, J. M.; Duffard, R.; Florczak, M.

    2002-09-01

    Informations about the compositional and mineralogical properties of a large sample of asteroids is important to better constraint their formation and evolution. In this sense large surveys have been performed in the last years either through photometric or spectroscopic observations (ex.: ECAS, 52colours, SMASS, etc.) with nearly 2000 asteroids sampled. However, in view of the steadly increasing number of known asteroids this sample is still in need of more data in order to have a complete knowledge of the distribution of compositions. The purpose of the Small Solar System Objects Spectroscopic Survey - S3OS2, was to contribute to increase the database of known superficial composition of asteroids in the visible range. The S3OS2 was performed at the European Southern Observatory (La Silla, Chile) under the agreement with the Observatorio Nacional, using the 1.52-m telescope equipped with a Boller & Chivens Spectrograph and a CCD. The survey was carried on from November 1996 up to September 2001 and visible spectra, in the range 4900-9200 Angstrom, were obtained for 843 asteroids. All these spectra will be available at the homepage of the Observatorio Nacional (http://www.on.br/institucional/) starting on October/2002. The taxonomic classification of all the sample will also be available at the same site. The spatial distribution of S3OS2 range from the Near Earth region, around 1.5 AU, up the Trojan region, around 5.2AU. Several families have been studied as well as several groups, all of which have been object of specific papers. In this presentation we will discuss the general properties and results of the survey, in view of what these represent for a better understanding about the formation and subsequent collisional and dynamical evolution of the asteroid belt as a whole. The author acknowledge the funding from CNPq, FAPERJ and CAPES.

  10. [Os(IV)Cl(5)(Hazole)](-) complexes: synthesis, structure, spectroscopic properties, and antiproliferative activity.

    PubMed

    Büchel, Gabriel E; Stepanenko, Iryna N; Hejl, Michaela; Jakupec, Michael A; Arion, Vladimir B; Keppler, Bernhard K

    2009-11-16

    By exploring the Anderson type rearrangement reactions, osmium(IV) complexes of the general formula [cation](+)[Os(IV)Cl(5)(Hazole)](-), where [cation](+) = n-Bu(4)N(+), Hazole = 1H-pyrazole (Hpz) (1), 1H-indazole (Hind) (2), 1H-imidazole (Him) (3), 1H-benzimidazole (Hbzim) (4), 1H,2,4-triazole (Htrz) (5), have been synthesized. To improve water solubility of tetrabutylammonium compounds, complexes with [cation](+) = Na(+) [Hazole = Hpz 6), Hind (7), Htrz (8)] or H(2)azole(+) [Hazole = Hpz (9), Hind (10), Htrz (11)] have been also prepared with the aim of testing them for cytotoxicity in cancer cells. In addition, the preparation of the complex {(n-Bu(4)N)(2)[Os(IV)Cl(6)]}(2)[Os(IV)Cl(4)(Him)(2)] (12) is also reported. The compounds have been comprehensively characterized by elemental analysis, electrospray ionization (ESI) mass spectrometry, spectroscopy (IR, UV-vis, 1D and 2D NMR), cyclic voltammetry, X-ray crystallography (1-6 and 12) and magnetic susceptibility (5). Complexes 6, 7, 9 are kinetically inert in aqueous solution and resistant to hydrolysis. Compounds 6-11 were found to possess modest antiproliferative acitivity in vitro against CH1 (ovarian carcinoma), A549 (non-small cell lung carcinoma), and SW480 (colon adenocarcinoma) cells with IC(50) values in the 10(-4) M concentration range. Replacement of azolium cations by sodium had significant effects; cytotoxicity increased in the case of the pyrazole system from 3 (A549) to the 5.5-fold (CH1).

  11. STRCMACS: An extensive set of Macros for structured programming in OS/360 assembly language

    NASA Technical Reports Server (NTRS)

    Barth, C. W.

    1974-01-01

    Two techniques are discussed that have been most often referred to as structured programming. One is that of programming with high level control structures (such as the if and while) replacing the branch instruction (goto-less programming); the other is the process of developing a program by progressively refining descriptions of components in terms of more primitive components (called stepwise refinement or top-down programming). In addition to discussing what these techniques are, it is shown why their use is advised and how both can be implemented in OS assembly language by the use of a special macro instruction package.

  12. Serum Phosphate Is Associated With Fracture Risk: The Rotterdam Study and MrOS.

    PubMed

    Campos-Obando, Natalia; Koek, W Nadia H; Hooker, Elizabeth R; van der Eerden, Bram Cj; Pols, Huibert A; Hofman, Albert; van Leeuwen, Johannes Ptm; Uitterlinden, Andre G; Nielson, Carrie M; Zillikens, M Carola

    2017-02-08

    Extreme phosphate levels (P) have been associated with mineralization defects and increased fracture risk. Whether P within normal range is related to bone health in the general population is not well understood. To investigate the association of P with bone mineral density (BMD) and fracture risk, we assessed two population-based cohorts: the Dutch Rotterdam Study (RS-I, RS-II, RS-III; n = 6791) and the US Osteoporotic Fractures in Men (MrOS; n = 5425) study. The relationship of P with lumbar spine (LS) and femoral neck (FN) BMD was tested in all cohorts via linear models; fracture risk was tested in RS-I, RS-II, and MrOS through Cox models, after follow-up of 8.6, 6.6, and 10.9 years, respectively. Adjustments were made for age, body mass index, smoking, serum levels of calcium, potassium, 25-hydroxyvitamin D, estimated glomerular filtration rate (eGFR), FN-BMD, prevalent diabetes, and cardiovascular disease. Additional adjustments were made for phosphate intake, parathyroid hormone, and fibroblast growth factor 23 levels in MrOS. We further stratified by eGFR. Results were pooled through study-level meta-analyses. Hazard ratios (HR) and betas (β) (from meta-analyses) are expressed per 1 mg/dL P increase. P was positively associated with fracture risk in men and women from RS, and findings were replicated in MrOS (pooled HR all [95% CI]: 1.47 [1.31-1.65]). P was associated with fracture risk in subjects without chronic kidney disease (CKD): all (1.44 [1.26-1.63]) and in men with CKD (1.93 [1.42-2.62]). P was inversely related to LS-BMD in men (β: -0.06 [-0.11 to -0.02]) and not to FN-BMD in either sex. In summary, serum P was positively related to fracture risk independently from BMD and phosphate intake after adjustments for potential confounders. P and LS-BMD were negatively related in men. Our findings suggest that increased P levels even within normal range might be deleterious for bone health in the normal population. © 2017 American Society for

  13. Elastic and electronic properties calculations of the filled skutterudite CeOs4P12

    NASA Astrophysics Data System (ADS)

    Merabet, M.; Djoudi, L.; Benalia, S.; Dahmane, F.; Boucharef, M.; Rached, D.; Rached, H.

    2016-10-01

    The full-potential linear muffin-tin orbital method (FP-LMTO) within the local density approximation (LDA) using the Perdew-Wang parameterization is used to calculate the structural, electronic and elastic properties of the filled skutterudite CeOs4P12. The results of the electronic properties show that this compound is an indirect band gap material (T -N). A special interest has been made to the determination of the elastic constants since there have been no available experimental and theoretical data. The energy band gaps and their volume and pressure dependence are also investigated.

  14. Ferromagnetism in the Mott insulator Ba2NaOsO6

    SciTech Connect

    Erickson, A.S.; Misra, S.; Miller, G.J.; Harrison, W.A.; Kim, J.M.; Fisher, I.R.; /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.

    2010-01-15

    Results are presented of single crystal structural, thermodynamic, and reflectivity measurements of the double-perovskite Ba{sub 2}NaOsO{sub 6}. These characterize the material as a 5d1 ferromagnetic Mott insulator with an ordered moment of {approx} 0.2 {micro}B per formula unit and T{sub C} = 6.8(3) K. The magnetic entropy associated with this phase transition is close to Rln2, indicating that the quartet groundstate anticipated from consideration of the crystal structure is split, consistent with a scenario in which the ferromagnetism is associated with orbital ordering.

  15. Os Isotopic Signature of Backarc Abyssal Peridotites from the Godzilla Megamullion

    NASA Astrophysics Data System (ADS)

    Nelson, W. R.; Snow, J. E.; Ohara, Y.; Brandon, A. D.

    2012-12-01

    Backarc seafloor spreading is a unique form of extension intimately tied to subduction zone dynamics. Unlike volcanism at mid-ocean ridges, backarc volcanism evolves from arc-like to MORB-like compositions over the short lifespan (~15 Ma) of the backarc. Our understanding of the evolution of oceanic mantle during backarc extension is limited to exposures of abyssal peridotite and ophiolites. While some ophiolites are thought to have formed in a backarc environment, few direct comparisons of ophiolite and backarc peridotite have been made due to the dearth of documented exposures and limited in situ samples from backarc settings. As a consequence, isotopic investigations have thus far been limited to ophiolite and mid-ocean ridge settings, limiting our understanding of the backarc oceanic mantle. Here we report preliminary Os isotopic data for backarc abyssal peridotites from the Godzilla Megamullion, a massive ~9000 km2 oceanic core complex located in the Parece Vela Basin (Philippine Sea). In this region, Izu-Bonin-Mariana subduction zone is responsible for creating the Parece Vella and Shikoku backarc basins as well as the Mariana Trough. In the last decade, five expeditions have collectively sampled the length of the Godzilla Megamullion. The distal end records early, magmatically productive extension marked by moderately depleted spinel peridotites. This transitions into a less melt-productive medial region characterized by more fertile peridotite. The proximal region represents the most recently exhumed portion of the megamullion and was the focus of the latest (October 2011) mapping and sampling expedition. Ultramafic samples from the proximal region are dominantly spinel lherzolite +/- plagioclase. Spinel grains record high TiO2 and Cr# produced by melt stagnating and interacting with the mantle. Whole rock 187Os/188Os (0.1245-0.1295) ranges from mildly subchondritic to PUM values, consistent with abyssal peridotites from mid-ocean ridge settings. The

  16. Inelastic scattering of 45-keV neutrons by {sup 187}Os

    SciTech Connect

    Litvinskii, L.L.; Zhigalov, Ya.A.; Libman, V.A.; Murzin, A.V.; Shkarupa, A.M.

    1995-02-01

    The cross sections of elastic and inelastic scattering of 45-keV neutrons by {sup 187}Os are measured by the technique of filtered neutron beams at the Kiev VVR-M reactor and are found to be {sigma}{sub e1} = 11.90 {+-} 0.50 b and {sigma}{sub inel} = 1.51 {+-} 0.45 b, respectively. These results confirm the existence of a nonstatistical enhancement of the inelastic-scattering channel due to a noticeable contribution of a preequilibrium state involving two particles and a hole. 8 refs., 1 fig.

  17. Spirituality Among Latinas/os Implications of Culture in Conceptualization and Measurement

    PubMed Central

    Campesino, Maureen; Schwartz, Gary E.

    2009-01-01

    Despite growing transnational migration between the United States and Latin American countries, culturally relevant conceptualizations of spirituality among Latinas/os remain lacking in healthcare research. Grounded in Latina feminist theology, this article elucidates cultural values that influence spirituality and describes findings from a study using a new questionnaire to explore spirituality among Latinas in Puerto Rico and the US mainland. Results support the saliency of cultural values such as personalismo and familismo as the context for spiritual perspectives, which may function independently of the Catholic Church structure. PMID:16495689

  18. Spirituality among Latinas/os: implications of culture in conceptualization and measurement.

    PubMed

    Campesino, Maureen; Schwartz, Gary E

    2006-01-01

    Despite growing transnational migration between the United States and Latin American countries, culturally relevant conceptualizations of spirituality among Latinas/os remain lacking in healthcare research. Grounded in Latina feminist theology, this article elucidates cultural values that influence spirituality and describes findings from a study using a new questionnaire to explore spirituality among Latinas in Puerto Rico and the US mainland. Results support the saliency of cultural values such as personalismo and familismo as the context for spiritual perspectives, which may function independently of the Catholic Church structure.

  19. [Presence of botulinum-producing clostridia in the soils of Entre Ríos].

    PubMed

    Lúquez, C; Fernández, R A; Bianco, M I; de Jong, L I T; Saldaño, V; Ciccarelli, A S

    2003-01-01

    Botulism, well known for centuries, continues to preoccupy the Public Health authorities, food and agricultural industries. In its oldest form it results from ingestion of food containing botulinum toxin. To correctly evaluate the incidence of botulism it is fundamental to know the distribution of botulinum toxin-producing clostridia (Clostridium botulinum, C. baratii, C. butyricum and C. argentinense) in nature, specially in the soil, its main reservoir. In our country, this study has been carried out in a partial way. With the aim to contribute to such knowledge, 240 soil samples from Entre Ríos province were examined for C. botulinum and 35 (14.6%) samples resulted positive.

  20. Mixing the mantle marble-cake: timescale constraints from Os isotopes

    NASA Astrophysics Data System (ADS)

    Parman, S.; Pearson, G.; Nowell, G.; van Hunen, J.

    2007-12-01

    In their seminal paper, Allegre and Turcotte (1986) presented a model in which the upper mantle is a mixture of depleted, harzburgitic mantle and subducted basalt that has been mechanically mixed together, the mantle marble-cake. Since their publication, most studies of mantle heterogeneity have focused on the enriched components, which are equated with subducted basalt and/or sediments, and successfully explain OIB Sr-Nd-Pb isotopic systematics. In this talk, we will focus on a different part of the marble-cake, depleted (harzburgitic) heterogeneities. Though abundant in abyssal peridotites and ophiolites, these have been difficult to study geochemically because they have very low concentrations of typical trace elements and radiogenic isotopes, and are overprinted by any mixing with enriched mantle or melts. However, Os is compatible during mantle melting, is enriched in depleted mantle and thus is robust with respect to mixing with enriched components or metasomatism. Somewhat surprisingly, Os isotope studies of the convecting mantle show clear evidence for depleted heterogeities up to 2 billion years old, but the relative paucity of data (less than 100 analyses), makes it difficult to extract meaningful mixing information. Rapid analysis of osmiridium grains by laser-ablation inductively coupled multi-collector plasma mass spectrometry now allows large Os datasets to be acquired (100s of datapoints), which are suitable for statistical analyses (Meibom, 2002). Here we present new and published laser-ablation analyses of osmiridiums from a global collection. The data generally show an exponential decrease in heterogeneities with age, such that over 90% of heterogeneities are destroyed within 2 billion years, though rare heterogeneities as old as 2.7 Ga survive. The exponential decrease in survivorship is generally consistent with the mechanical mixing model of Allegre & Turcotte (1986). Subsequent 2-dimensional mixing models suggest that high-viscosity blobs can

  1. A rice jacalin-related mannose-binding lectin gene, OsJRL, enhances Escherichia coli viability under high salinity stress and improves salinity tolerance of rice.

    PubMed

    He, X; Li, L; Xu, H; Xi, J; Cao, X; Xu, H; Rong, S; Dong, Y; Wang, C; Chen, R; Xu, J; Gao, X; Xu, Z

    2017-03-01

    Salinity, which is one of the most common abiotic stresses, may severely affect plant productivity and quality. Although plant lectins are thought to play important roles in plant defense signaling during pathogen attack, little is known about the contribution of plant lectins to stress resistance. We cloned and functionally characterized a rice jacalin-related mannose-binding lectin gene, OsJRL, from rice 'Nipponbare'. We analyzed the expression patterns of OsJRL under various stress conditions in rice. Furthermore, we overexpressed OsJRL in Escherichia coli and rice. The cDNA of OsJRL contained a 438 bp open reading frame, which encodes a polypeptide of 145 amino acids. OsJRL was localized in the nucleus and cytoplasm. Real time PCR analyses revealed that OsJRL expression showed tissue specificity in rice and was upregulated under diverse stresses, namely salt, drought, cold, heat and abscisic acid treatments. Overexpression of OsJRL in E. coli enhanced cell viability and dramatically improved tolerance of high salinity. Overexpression of OsJRL in rice also enhanced salinity tolerance and increased the expression levels of a number of stress-related genes, including three LEA (late embryogenesis abundant proteins) genes (OsLEA19a, OsLEA23 and OsLEA24), three Na(+) transporter genes (OsHKT1;3, OsHKT1;4 and OsHKT1;5) and two DREB genes (OsDREB1A and OsDREB2B). Based on these results, we suggest that OsJRL plays an important role in cell protection and stress signal transduction.

  2. The protein phosphatase 2C clade A protein OsPP2C51 positively regulates seed germination by directly inactivating OsbZIP10.

    PubMed

    Bhatnagar, Nikita; Min, Myung-Ki; Choi, Eun-Hye; Kim, Namhyo; Moon, Seok-Jun; Yoon, Insun; Kwon, Taekryoun; Jung, Ki-Hong; Kim, Beom-Gi

    2017-03-01

    Protein phosphatase 2C clade A members are major signaling components in the ABA-dependent signaling cascade that regulates seed germination. To elucidate the role of PP2CA genes in germination of rice seed, we selected OsPP2C51, which shows highly specific expression in the embryo compared with other protein phosphatases based on microarray data. GUS histochemical assay confirmed that OsPP2C51 is expressed in the seed embryo and that this expression pattern is unique compared with those of other OsPP2CA genes. Data obtained from germination assays and alpha-amylase assays of OsPP2C51 knockout and overexpression lines suggest that OsPP2C51 positively regulates seed germination in rice. The expression of alpha-amylase synthesizing genes was high in OsPP2C51 overexpressing plants, suggesting that elevated levels of OsPP2C51 might enhance gene expression related to higher rates of seed germination. Analysis of protein interactions between ABA signaling components showed that OsPP2C51 interacts with OsPYL/RCAR5 in an ABA-dependent manner. Furthermore, interactions were observed between OsPP2C51 and SAPK2, and between OsPP2C51 and OsbZIP10 and we found out that OsPP2C51 can dephosphorylates OsbZIP10. These findings suggest the existence of a new branch in ABA signaling pathway consisting of OsPYL/RCAR-OsPP2C-bZIP apart from the previously reported OsPYL/RCAR-OsPP2C-SAPK-bZIP. Overall, our result suggests that OsPP2C51 is a positive regulator of seed germination by directly suppressing active phosphorylated OsbZIP10.

  3. An osmium(III)/osmium(V) redox couple generating Os(V)(O)(OH) center for cis-1,2-dihydroxylation of alkenes with H2O2: Os complex with a nitrogen-based tetradentate ligand.

    PubMed

    Sugimoto, Hideki; Kitayama, Kazuhiro; Mori, Seiji; Itoh, Shinobu

    2012-11-21

    For the synthesis of the 1,2-diols, cis-1,2-dihydroxylation of alkenes catalyzed by osmium(VIII) tetroxide (OsO(4)) is a powerful method. However, OsO(4) is quite toxic due to its highly volatile and sublimable nature. Thus, the development of alternative catalysts for cis-1,2-dihydroxylation of alkenes is highly challenging. Our approach involves the use of a nitrogen-based tetradentate ligand, tris(2-pyridylmethyl)amine (tpa), for an osmium center to develop a new osmium catalyst and hydrogen peroxide (H(2)O(2)) as a cheap and environmentally benign oxidant. The new Os-tpa complex acts as a very efficient turnover catalyst for syn-selective dihydroxylation of various alkenes (turnover number ∼1000) in aqueous media, and H(2)O(2) oxidant is formally incorporated into the products quantitatively (100% atom efficiency). The reaction intermediates involved in the catalytic cycle have been isolated and characterized crystallographically as [Os(III)(OH)(H(2)O)(tpa)](2+) and [Os(V)(O)(OH)(tpa)](2+) complexes. The observed syn-selectivity, structural characteristics of the intermediates, and kinetic studies have suggested a concerted [3 + 2]-cycloaddition mechanism between [Os(V)(O)(OH)(tpa)](2+) and alkenes, which is strongly supported by DFT calculations.

  4. High-pressure synthesis, crystal structure, and magnetic properties of KSbO3-type 5d oxides K0.84OsO3 and Bi2.93Os3O11

    PubMed Central

    Yuan, Yahua; Feng, Hai L; Shi, Youguo; Tsujimoto, Yoshihiro; Belik, Alexei A; Matsushita, Yoshitaka; Arai, Masao; He, Jianfeng; Tanaka, Masahiko; Yamaura, Kazunari

    2014-01-01

    5d Solid-state oxides K0.84OsO3 (Os5.16+; 5d 2.84) and Bi2.93Os3O11 (Os4.40+; 5d 3.60) were synthesized under high-pressure and high-temperature conditions (6 GPa and 1500–1700 °C). Their crystal structures were determined by synchrotron x-ray diffraction and their 5d electronic properties and tunnel-like structure motifs were investigated. A KSbO3-type structure with a space group of Im-3 and Pn-3 was determined for K0.84OsO3 and Bi2.93Os3O11, respectively. The magnetic and electronic transport properties of the polycrystalline compounds were compared with those obtained theoretically. It was revealed that the 5d tunnel-like structures are paramagnetic with metallic charge conduction at temperatures above 2 K. This was similar to what was observed for structurally relevant 5d oxides, including Bi3Re3O11 (Re4.33+; 5d 2.66) and Ba2Ir3O9 (Ir4.66+; 5d 4.33). The absence of long-range magnetic order seems to be common among 5d KSbO3-like oxides, regardless of the number of 5d electrons (between 2.6 and 4.3 per 5d atom). PMID:27877729

  5. Cloning and characterization of the drought-resistance OsRCI2-5 gene in rice (Oryza sativa L.).

    PubMed

    Li, L; Li, N; Song, S F; Li, Y X; Xia, X J; Fu, X Q; Chen, G H; Deng, H F

    2014-05-23

    The genomic expression profile of the super-hybrid rice Liangyoupeijiu female parent Pei'ai 64S in different tissues at different developmental stages under low temperature, drought, and high temperature stresses were detected using an Affymetrix GeneChip Rice Genome Array to screen upregulated and downregulated genes. In this study, we screened the drought-resistant gene OsRCI2-5, after which a constitutive OsRCI2-5 construct was created and transferred into Nipponbare. After polyethylene glycol-6000 and drought treatment, we found that the OsRCI2-5 gene improved the drought resistance of Nipponbare. Gene expression profiling showed that the OsRCI2-5 gene was expressed in the rice leaves, stems, and flower organs. Subcellular localization revealed that the gene was located in the membranes, and hence, we can deduce that a membrane signal peptide was responsible for signal transduction.

  6. Interaction of structural core protein of classical swine fever virus with endoplasmic reticulum-associated degradation pathway protein OS9.

    PubMed

    Gladue, D P; O'Donnell, V; Fernandez-Sainz, I J; Fletcher, P; Baker-Branstetter, R; Holinka, L G; Sanford, B; Carlson, J; Lu, Z; Borca, M V

    2014-07-01

    Classical swine fever virus (CSFV) Core protein is involved in virus RNA protection, transcription regulation and virus virulence. To discover additional Core protein functions a yeast two-hybrid system was used to identify host proteins that interact with Core. Among the identified host proteins, the osteosarcoma amplified 9 protein (OS9) was further studied. Using alanine scanning mutagenesis, the OS9 binding site in the CSFV Core protein was identified, between Core residues (90)IAIM(93), near a putative cleavage site. Truncated versions of Core were used to show that OS9 binds a polypeptide representing the 12 C-terminal Core residues. Cells transfected with a double-fluorescent labeled Core construct demonstrated that co-localization of OS9 and Core occurred only on unprocessed forms of Core protein. A recombinant CSFV containing Core protein where residues (90)IAIM(93) were substituted by alanines showed no altered virulence in swine, but a significant decreased ability to replicate in cell cultures.

  7. Overexpression of Rice Wall-Associated Kinase 25 (OsWAK25) Alters Resistance to Bacterial and Fungal Pathogens

    PubMed Central

    Harkenrider, Mitch; Sharma, Rita; De Vleesschauwer, David; Tsao, Li; Zhang, Xuting; Chern, Mawsheng; Canlas, Patrick; Zuo, Shimin; Ronald, Pamela C.

    2016-01-01

    Wall-associated kinases comprise a sub-family of receptor-like kinases that function in plant growth and stress responses. Previous studies have shown that the rice wall-associated kinase, OsWAK25, interacts with a diverse set of proteins associated with both biotic and abiotic stress responses. Here, we show that wounding and BTH treatments induce OsWAK25 transcript expression in rice. We generated OsWAK25 overexpression lines and show that these lines exhibit a lesion mimic phenotype and enhanced expression of rice NH1 (NPR1 homolog 1), OsPAL2, PBZ1 and PR10. Furthermore, these lines show resistance to the hemibiotrophic pathogens, Xanthomonas oryzae pv. oryzae (Xoo) and Magnaporthe oryzae, yet display increased susceptibility to necrotrophic fungal pathogens, Rhizoctonia solani and Cochliobolus miyabeanus. PMID:26795719

  8. The variability of the volume of os coxae and linear pelvic morphometry. Considerations for total hip arthroplasty.

    PubMed

    Solomon, Lucian B; Howie, Donald W; Henneberg, Maciej

    2014-04-01

    This study investigated the variability of os coxae's volume and linear morphometry in 50 dry adult bones. There was a wide variability, with coefficients of variation exceeding 30%, of the bones' volumes (mean 142 ml, range 80 to 300 ml) and distances between the acetabular rim and the horizontal plane through the sciatic notch (mean 10.6 mm, range -7 to 19 mm). The smallest width of the ilium ranged between 3 and 9 mm at a level between 1.5 and 4 cm above the acetabulum. The volume of os coxae correlated with the acetabular diameter (r = 0.79), the height of os coxae (r = 0.88) and antero-posterior length of the ilium at mid-acetabular level (r = 0.70). Knowledge of the variability of os coxae may be useful during preoperative planning in primary and revision hip arthroplasty.

  9. Structure and physical properties of the polar oxysulfide CaZnOS.

    PubMed

    Sambrook, Timothy; Smura, Catherine F; Clarke, Simon J; Ok, Kang Min; Halasyamani, P Shiv

    2007-04-02

    The synthesis, structure, and electrical properties of the oxysulfide CaZnOS are reported. The white compound has a band gap of 3.7(1) eV and crystallizes in hexagonal space group P6(3)mc (No. 186) with a = 3.75726(3) A, c = 11.4013(1) A, and Z = 2. The noncentrosymmetric structure, which has few analogues, is composed of isotypic puckered hexagonal ZnS and CaO layers arranged so that ZnS3O tetrahedra are all aligned parallel, resulting in a polar structure. The compound shows type 1 non-phase-matchable second harmonic generation, determined using 1064 nm radiation, with an efficiency approximately 100 times that of alpha-SiO2 and a piezoelectric coefficient of 38 pm V-1. Although polar, CaZnOS is not ferroelectric and the pyroelectric coefficient is very small, approximately 0.0 microC m-2 K-1 between room temperature and 100 degrees C.

  10. A single amino acid mutation of OsSBEIIb contributes to resistant starch accumulation in rice

    PubMed Central

    Yang, Ruifang; Bai, Jianjiang; Fang, Jun; Wang, Ying; Lee, Gangseob; Piao, Zhongze

    2016-01-01

    Foods rich in resistant starch can help prevent various diseases, including diabetes, colon cancers, diarrhea, and chronic renal and hepatic diseases. Variations in starch biosynthesis enzymes could contribute to the high content of resistant starch in some cultivars of rice (Oryza sativa L.). Our previously published work indicated that the sbe3-rs gene in the rice mutant line, ‘Jiangtangdao1’ was a putative allele of the rice starch branching enzyme gene SBEIIb (previously known as SBE3); sbe3-rs might control the biosynthesis of the high resistant starch content in the rice line. Biomolecular analysis showed that the activity of SBEs was significantly lower in soluble extracts of immature seeds harvested from ‘Jiangtangdao1’ 15 days after flowering than in the extracts of the wild-type rice line ‘Huaqingdao’. We performed gene complementation assays by introducing the wild-type OsSBEIIb into the sbe3-rs mutant ‘Jiangtangdao1’. The genetically complemented lines demonstrated restored seed-related traits. The structures of endosperm amylopectin and the morphological and physicochemical properties of the starch granules in the transformants recovered to wild-type levels. This study provides evidence that sbe3-rs is a novel allele of OsSBEIIb, responsible for biosynthesis of high resistant starch in ‘Jiangtangdao1’. PMID:27795673

  11. Osteometric sex estimation from the os coxa in a Thai population.

    PubMed

    Mahakkanukrauh, Pasuk; Ruengdit, Sittiporn; Tun, Saw Myint; Case, D Troy; Sinthubua, Apichat

    2017-02-01

    The coxal bone shows a very high degree of sexual dimorphism both morphologically and metrically. However, despite a number of recent studies on sex estimation from the skeleton in Thailand, no osteometric methods of sexing the Thai os coxa have been proposed. Therefore, the aim of this study was to develop a standard sex estimation method for a Thai population by examining the efficacy of six coxal bone measurements and eight indices obtained from 200 Thai skeletons. Independent samples t-tests revealed statistically significant differences between males and females for all but one of the measurements. The equation with the highest correct allocation accuracy was based on four measurements (pubis length, ischium length, total height and acetabulum diameter) and had a predicted and cross-validated accuracy of 96.9% and a tested accuracy of 97.5% on a holdout sample of 40 individuals. The single variable equation with the highest correct allocation accuracy of 94.4% and a tested accuracy of 97.5% was for the ischiopubic index, which is calculated from ischium length and pubis length. Percentage accuracies in predicting sex from these equations were higher than many previous studies, suggesting high levels of sexual dimorphism in the Thai os coxa.

  12. Ab initio study of interstitial cluster interaction with Re, Os, and Ta in W

    NASA Astrophysics Data System (ADS)

    Setyawan, Wahyu; Nandipati, Giridhar; Kurtz, Richard J.

    2017-02-01

    The stability of tungsten self-interstitial atom (SIA) clusters is studied using first-principles methods. Clusters from one to seven SIAs are systematically explored from 1264 unique configurations. Finite-size effect of the simulation cell is corrected based on the scaling of formation energy versus inverse volume cell. Furthermore, the accuracy of the calculations is improved by treating the 5p semicore states as valence states. Configurations of the three most stable clusters in each cluster size n are presented, which consist of parallel [111] dumbbells. The evolution of these clusters leading to small dislocation loops is discussed. The binding energy of size-n clusters is analyzed relative to an n → (n-1) + 1 dissociation and is shown to increase with size. Extrapolation for n > 7 is presented using a dislocation loop model. In addition, the interaction of these clusters with a substitutional Re, Os, or Ta solute is explored by replacing one of the dumbbells with the solute. Re and Os strongly attract these clusters, but Ta strongly repels. The strongest interaction is found when the solute is located on the periphery of the cluster rather than in the middle. The magnitude of this interaction decreases with cluster size. Empirical fits to describe the trend of the solute binding energy are presented.

  13. Triaxial rotor model description of E2 properties in {sup 186,188,190,192}Os

    SciTech Connect

    Allmond, J. M.; Zaballa, R.; Oros-Peusquens, A. M.; Kulp, W. D.; Wood, J. L.

    2008-07-15

    The triaxial rotor model with independent inertia and electric quadrupole tensors is applied to the description of the extensive set of E2 matrix elements available for {sup 186,188,190,192}Os. Most large and medium transition E2 matrix elements can be reproduced to within {approx}10%, and most diagonal elements to within {approx}30%. Most small transition matrix elements can be reproduced to within {approx}30%, and they support the interference effect exhibited by the model between the inertia and E2 tensors: this is a new feature of quantum rotor models. The diagonal E2 matrix elements at higher spins in the K=2 band are extremely sensitive to admixtures of higher K values: the low experimental values in {sup 190,192}Os indicate significant admixtures of K=4 components. Attention is given to the K{sup {pi}}=4{sup +} bands in these nuclei and the controversial issue of whether they are of quadrupole or hexadecapole nature.

  14. Lattice-site-specific spin dynamics in double perovskite Sr2CoOsO6.

    PubMed

    Yan, Binghai; Paul, Avijit Kumar; Kanungo, Sudipta; Reehuis, Manfred; Hoser, Andreas; Többens, Daniel M; Schnelle, Walter; Williams, Robert C; Lancaster, Tom; Xiao, Fan; Möller, Johannes S; Blundell, Stephen J; Hayes, William; Felser, Claudia; Jansen, Martin

    2014-04-11

    Magnetic properties and spin dynamics have been studied for the structurally ordered double perovskite Sr2CoOsO6. Neutron diffraction, muon-spin relaxation, and ac-susceptibility measurements reveal two antiferromagnetic (AFM) phases on cooling from room temperature down to 2 K. In the first AFM phase, with transition temperature TN1=108  K, cobalt (3d7, S=3/2) and osmium (5d2, S=1) moments fluctuate dynamically, while their average effective moments undergo long-range order. In the second AFM phase below TN2=67  K, cobalt moments first become frozen and induce a noncollinear spin-canted AFM state, while dynamically fluctuating osmium moments are later frozen into a randomly canted state at T≈5  K. Ab initio calculations indicate that the effective exchange coupling between cobalt and osmium sites is rather weak, so that cobalt and osmium sublattices exhibit different ground states and spin dynamics, making Sr2CoOsO6 distinct from previously reported double-perovskite compounds.

  15. A single amino acid mutation of OsSBEIIb contributes to resistant starch accumulation in rice.

    PubMed

    Yang, Ruifang; Bai, Jianjiang; Fang, Jun; Wang, Ying; Lee, Gangseob; Piao, Zhongze

    2016-09-01

    Foods rich in resistant starch can help prevent various diseases, including diabetes, colon cancers, diarrhea, and chronic renal and hepatic diseases. Variations in starch biosynthesis enzymes could contribute to the high content of resistant starch in some cultivars of rice (Oryza sativa L.). Our previously published work indicated that the sbe3-rs gene in the rice mutant line, 'Jiangtangdao1' was a putative allele of the rice starch branching enzyme gene SBEIIb (previously known as SBE3); sbe3-rs might control the biosynthesis of the high resistant starch content in the rice line. Biomolecular analysis showed that the activity of SBEs was significantly lower in soluble extracts of immature seeds harvested from 'Jiangtangdao1' 15 days after flowering than in the extracts of the wild-type rice line 'Huaqingdao'. We performed gene complementation assays by introducing the wild-type OsSBEIIb into the sbe3-rs mutant 'Jiangtangdao1'. The genetically complemented lines demonstrated restored seed-related traits. The structures of endosperm amylopectin and the morphological and physicochemical properties of the starch granules in the transformants recovered to wild-type levels. This study provides evidence that sbe3-rs is a novel allele of OsSBEIIb, responsible for biosynthesis of high resistant starch in 'Jiangtangdao1'.

  16. Predicting a ferrimagnetic phase of Zn(2)FeOsO(6) with strong magnetoelectric coupling.

    PubMed

    Wang, P S; Ren, W; Bellaiche, L; Xiang, H J

    2015-04-10

    Multiferroic materials, in which ferroelectric and magnetic ordering coexist, are of practical interest for the development of novel memory devices that allow for electrical writing and nondestructive magnetic readout operation. The great challenge is to create room temperature multiferroic materials with strongly coupled ferroelectric and ferromagnetic (or ferrimagnetic) orderings. BiFeO_{3} is the most heavily investigated single-phase multiferroic to date due to the coexistence of its magnetic order and ferroelectric order at room temperature. However, there is no net magnetic moment in the cycloidal (antiferromagneticlike) magnetic state of bulk BiFeO_{3}, which severely limits its realistic applications in electric field controlled memory devices. Here, we predict that LiNbO_{3}-type Zn_{2}FeOsO_{6} is a new multiferroic with properties superior to BiFeO_{3}. First, there are strong ferroelectricity and strong ferrimagnetism at room temperature in Zn_{2}FeOsO_{6}. Second, the easy plane of the spontaneous magnetization can be switched by an external electric field, evidencing the strong magnetoelectric coupling existing in this system. Our results suggest that ferrimagnetic 3d-5d LiNbO_{3}-type material may therefore be used to achieve voltage control of magnetism in future memory devices.

  17. Predicting a Ferrimagnetic Phase of Zn2FeOsO6 with Strong Magnetoelectric Coupling

    NASA Astrophysics Data System (ADS)

    Wang, P. S.; Ren, W.; Bellaiche, L.; Xiang, H. J.

    2015-04-01

    Multiferroic materials, in which ferroelectric and magnetic ordering coexist, are of practical interest for the development of novel memory devices that allow for electrical writing and nondestructive magnetic readout operation. The great challenge is to create room temperature multiferroic materials with strongly coupled ferroelectric and ferromagnetic (or ferrimagnetic) orderings. BiFeO3 is the most heavily investigated single-phase multiferroic to date due to the coexistence of its magnetic order and ferroelectric order at room temperature. However, there is no net magnetic moment in the cycloidal (antiferromagneticlike) magnetic state of bulk BiFeO3 , which severely limits its realistic applications in electric field controlled memory devices. Here, we predict that LiNbO3 -type Zn2FeOsO6 is a new multiferroic with properties superior to BiFeO3 . First, there are strong ferroelectricity and strong ferrimagnetism at room temperature in Zn2FeOsO6 . Second, the easy plane of the spontaneous magnetization can be switched by an external electric field, evidencing the strong magnetoelectric coupling existing in this system. Our results suggest that ferrimagnetic 3 d -5 d LiNbO3 -type material may therefore be used to achieve voltage control of magnetism in future memory devices.

  18. RT/OS — realtime programming and application environment for the COSY control system

    NASA Astrophysics Data System (ADS)

    Weinert, A.; Hacker, U.; Haberbosch, Ch.; Henn, K.; Simon, M.

    1994-12-01

    This paper presents the highlights and constraints of RT/OS and how it can be used at other places. The support of approximately 1000 VME and VXI CPUs in network-based multiprocessor systems needs a special set of programming tools and application environment which are bundled as the RT/OS Real-Time-Operating-System. Supporting the Motorola 680χ0 processors and micro-controller with a development system on UNIX and MS-DOS platforms, the tool set gives the opportunity of bringing small embedded controllers as well as VME multiprocessor systems into operation. The tool set includes a cross compiler and a special version of a remote debugger, as well as application support such as downloading and configuration management. The main feature is a modular kernel with message-based task switching, using the rendezvous principle to allow easy extension. Special features of this kernel for a distributed system are networking with the Berkeley socket library supporting TCP/IP, XNS and Novell Netware, a multiprocessor system on VMEbus with the interprocessor Communication Module (IPC), a device driver library for almost every G64 I/O card using a FieldBus Interface called PDV and a X11R4 port.

  19. ESTIGMA Y VIH/SIDA ENTRE PADRES/MADRES Y ADOLESCENTES PUERTORRIQUEÑOS/AS

    PubMed Central

    Pérez, Grace Rosado; Reyes, Glendalys Rivera; Villanueva, Victoria Larrieux; Torres, Gilliam J. Torres; Díaz, Elba Betancourt; Varas-Díaz, Nelson; Villaruel, Antonia

    2016-01-01

    La comunicación entre padres/madres y adolescentes sobre el tema de la sexualidad es importante para el desarrollo de la salud de personas jóvenes. Dicha comunicación puede verse negativamente impactada por actitudes estigmatizantes hacia el tema del VIH/SIDA. El objetivo de este estudio fue identificar actitudes estigmatizantes hacia el VIH/SIDA entre padres/madres y adolescentes puertorriqueños/as. Este esfuerzo es parte del Proyecto Cuídalos, dirigido a probar una intervención en formato electrónico que busca aumentar la comunicación sobre sexualidad y salud entre padres/madres y adolescentes mediante un diseño experimental con 458 diadas de padres/madres y adolescentes de 13 a 17 años. Para propósitos de este artículo reportamos estadísticas descriptivas sobre estigma hacia el VIH/SIDA con la información recopilada en la medición basal. Tanto adultos/as como adolescentes mostraron actitudes estigmatizantes hacia el VIH/SIDA. A la luz de los resultados es necesario continuar desarrollando intervenciones para la reducción de estigma en esta población. Los/as padres/madres pueden ser un recurso invaluable para reducir el estigma en los/as jóvenes, y prevenir conductas sexuales de riesgo e infecciones. PMID:27099649

  20. [Phlebotominae: vectors of leishmaniasis in the provinces of Santa Fe and Entre Ríos, Argentina].

    PubMed

    Salomón, Oscar D; Mocarbel, Nicolás J; Pedroni, Elena; Colombo, Javier; Sandillú, Mónica

    2006-01-01

    The transmission of tegumentary leishmaniasis (TL) has increased in 9 provinces of Argentina since 1985. Santa Fe and Entre Ríos did not record in this period autochtonous probed cases: however, an epidemic outbreak took place in 2003 in Bella Vista, Corrientes, located in an area with ecological continuity and contiguous to both provinces. In order to evaluate the potential risk of transmission of LT, Phlebotominae were captured at locations close to and southern from Bella Vista during February 2004. The traps located on the shores of Parana river in Santa Fe (El Rabón, Villa Ocampo, Cayastá), and Entre Ríos (La Paz. La Celina-Villa Urquiza) captured 860 individuals of Lutzomyia neivai (99.5%) and Lu. migonei (0.5 %), both species with vectorial capacity for Leishmania (V.) braziliensis. In Tartagal, Santa Fe, the captures were consistent with the residual "chaco" landscape, 7 individuals of Lu. nerivai, Lu. migonei and Lu. cortelezzii. The risk of LT epidemic transmission in these provinces is highlighted, mainly due to the progressive southern tropicalization of the paranaense gallery forest. Clinical and entomological surveillance is recommended.

  1. Un kyste hydatique osseux: une localisation rare au niveau de l’os iliaque

    PubMed Central

    Nhamoucha, Yassine; Alaoui, Othmane; Doumbia, Aliou; Oukhoya, Mohammed; Abdellaoui, Hicham; Tazi, Mohammed; Chater, Lamyae; Atarraf, Karima; Arroud, Mounir; Afifi, Abderahman

    2016-01-01

    L'hydatidose est une affection parasitaire liée au développement chez l'homme de la forme larvaire d'un cestode, à savoir un tænia de très petite taille dénommé Echinococcus Granulosus. Cette anthropozoonose présente une diversité de formes anatomoradiologiques lié aux nombreux aspects topographiques et évolutifs des kystes. L'hydatidose osseuse est rare, elle ne représente que 0,9 à 2,5% de l'ensemble des localisations. Nous rapportons l'observation d'un enfant de 9 ans, qui a été admis chez nous pour une boiterie fébrile avec une masse au niveau de la fosse iliaque droite, révélant un kyste hydatique au dépend de l'os iliaque. Le bilan lésionnel avait objectivé un kyste hydatique de l'os iliaque avec extension aux parties molles adjacentes. Le traitement chirurgical conclu a un kyste surinfecté d'ou la réalisation d'une exérèse chirurgicale du kyste avec drainage. L'ostéopathie hydatique est infiltrante, diffuse, lente et progressive, ce qui rend le diagnostic tardif et qui compromet la qualité du traitement. PMID:27800081

  2. p27kip1 overexpression promotes paclitaxel-induced apoptosis in pRb-defective SaOs-2 cells.

    PubMed

    Gabellini, Chiara; Pucci, Bruna; Valdivieso, Paola; D'Andrilli, Giuseppina; Tafani, Marco; De Luca, Antonio; Masciullo, Valeria

    2006-08-15

    p27kip1 is a cyclin-dependent kinase (CDK) inhibitor, which controls several cellular processes in strict collaboration with pRb. We evaluated the role of p27kip1 in paclitaxel-induced apoptosis in the pRb-defective SaOs-2 cells. Following 48 h of exposure of SaOs-2 cells to 100 nM paclitaxel, we observed an increase in p27kip1 expression caused by the decrease of the ubiquitin-proteasome activity. Such increase was not observed in SaOs-2 cells treated with the caspase inhibitors Z-VAD-FMK, suggesting that p27kip1 enhancement at 48 h is strictly related to apoptosis. Finally, we demonstrated that SaOs-2 cells transiently overexpressing the p27kip1 protein are more susceptible to paclitaxel-induced apoptosis than SaOs-2 cells transiently transfected with the empty vector. Indeed, after 48 h of paclitaxel treatment, 41.8% of SaOs-2 cells transiently transfected with a pcDNA3-p27kip1 construct were Annexin V-positive compared to 30.6% of SaOs-2 cells transfected with the empty vector (P < 0.05). In conclusion, we demonstrated that transfection of the pRb-defective SaOs-2 cells with the p27kip1 gene via plasmid increases their susceptibility to paclitaxel-induced apoptosis. The promoting effect of p27kip1 overexpression on apoptosis makes p27kip1 and proteasomal inhibitors interesting tools for therapy in patients with pRb-defective cancers.

  3. OsMAPK6, a mitogen-activated protein kinase, influences rice grain size and biomass production.

    PubMed

    Liu, Shuying; Hua, Lei; Dong, Sujun; Chen, Hongqi; Zhu, Xudong; Jiang, Jun'e; Zhang, Fang; Li, Yunhai; Fang, Xiaohua; Chen, Fan

    2015-11-01

    Grain size is an important agronomic trait in determining grain yield. However, the molecular mechanisms that determine the final grain size are not well understood. Here, we report the functional analysis of a rice (Oryza sativa L.) mutant, dwarf and small grain1 (dsg1), which displays pleiotropic phenotypes, including small grains, dwarfism and erect leaves. Cytological observations revealed that the small grain and dwarfism of dsg1 were mainly caused by the inhibition of cell proliferation. Map-based cloning revealed that DSG1 encoded a mitogen-activated protein kinase (MAPK), OsMAPK6. OsMAPK6 was mainly located in the nucleus and cytoplasm, and was ubiquitously distributed in various organs, predominately in spikelets and spikelet hulls, consistent with its role in grain size and biomass production. As a functional kinase, OsMAPK6 interacts strongly with OsMKK4, indicating that OsMKK4 is likely to be the upstream MAPK kinase of OsMAPK6 in rice. In addition, hormone sensitivity tests indicated that the dsg1 mutant was less sensitive to brassinosteroids (BRs). The endogenous BR levels were reduced in dsg1, and the expression of several BR signaling pathway genes and feedback-inhibited genes was altered in the dsg1 mutant, with or without exogenous BRs, indicating that OsMAPK6 may contribute to influence BR homeostasis and signaling. Thus, OsMAPK6, a MAPK, plays a pivotal role in grain size in rice, via cell proliferation, and BR signaling and homeostasis.

  4. The influence of melt flux and crustal processing on Re-Os isotope systematics of ocean island basalts: Constraints from Galápagos

    NASA Astrophysics Data System (ADS)

    Gibson, S. A.; Dale, C. W.; Geist, D. J.; Day, J. A.; Brügmann, G.; Harpp, K. S.

    2016-09-01

    New rhenium-osmium data for high-MgO (>9 wt.%) basalts from the Galápagos Archipelago reveal a large variation in 187Os/188Os (0.1304 to 0.173), comparable with the range shown by primitive global ocean island basalts (OIBs). Basalts with the least radiogenic 187Os/188Os occur closest to the Galápagos plume stem: those in western Galápagos have low 187Os/188Os, moderate 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb and high 3He/4He whereas basalts in the south also have low 187Os/188Os but more radiogenic 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb and 3He/4He. Our new Os isotope data are consistent with the previously established spatial zonation of the common global isotopic mantle reservoir ;C; and ancient recycled oceanic crust in the mantle plume beneath western and southern parts of Galápagos, respectively. Galápagos basalts with the most radiogenic 187Os/188Os (up to 0.1875) typically have moderate MgO (7-9 wt.%) and low Os (<50 pg g-1) but have contrastingly unenriched Sr, Nd and Pb isotope signatures. We interpret this decoupling of chalcophile and lithophile isotopic systems as due to assimilation of young Pacific lower crust during crystal fractionation. Mixing models show the assimilated crust must have higher contents of Re and Os, and more radiogenic 187Os/188Os (0.32), than previously proposed for oceanic gabbros. We suggest the inferred, exceptionally-high radiogenic 187Os of the Pacific crust may be localised and due to sulfides precipitated from hydrothermal systems established at the Galápagos Spreading Centre. High 187Os/188Os Galápagos basalts are found where plume material is being dispersed laterally away from the plume stem to the adjacent spreading centre (i.e. in central and NE parts of the archipelago). The extent to which crustal processing influences 187Os/188Os appears to be primarily controlled by melt flux: as distance from the stem of the Galápagos plume increases, the melt flux decreases and crustal assimilation becomes proportionally

  5. AtlantOS - Optimizing and Enhancing the Integrated Atlantic Ocean Observing System

    NASA Astrophysics Data System (ADS)

    Reitz, Anja; Visbeck, Martin; AtlantOS Consortium, the

    2016-04-01

    Atlantic Ocean observation is currently undertaken through loosely-coordinated, in-situ observing networks, satellite observations and data management arrangements of heterogeneous international, national and regional design to support science and a wide range of information products. Thus there is tremendous opportunity to develop the systems towards a fully integrated Atlantic Ocean Observing System consistent with the recently developed 'Framework of Ocean Observing'. The vision of AtlantOS is to improve and innovate Atlantic observing by using the Framework of Ocean Observing to obtain an international, more sustainable, more efficient, more integrated, and fit-for-purpose system. Hence, the AtlantOS initiative will have a long-lasting and sustainable contribution to the societal, economic and scientific benefit arising from this integrated approach. This will be delivered by improving the value for money, extent, completeness, quality and ease of access to Atlantic Ocean data required by industries, product supplying agencies, scientist and citizens. The overarching target of the AtlantOS initiative is to deliver an advanced framework for the development of an integrated Atlantic Ocean Observing System that goes beyond the state-of -the-art, and leaves a legacy of sustainability after the life of the project. The legacy will derive from the following aims: i) to improve international collaboration in the design, implementation and benefit sharing of ocean observing, ii) to promote engagement and innovation in all aspects of ocean observing, iii) to facilitate free and open access to ocean data and information, iv) to enable and disseminate methods of achieving quality and authority of ocean information, v) to strengthen the Global Ocean Observing System (GOOS) and to sustain observing systems that are critical for the Copernicus Marine Environment Monitoring Service and its applications and vi) to contribute to the aims of the Galway Statement on Atlantic

  6. Overexpression of the CC-type glutaredoxin, OsGRX6 affects hormone and nitrogen status in rice plants

    PubMed Central

    El-Kereamy, Ashraf; Bi, Yong-Mei; Mahmood, Kashif; Ranathunge, Kosala; Yaish, Mahmoud W.; Nambara, Eiji; Rothstein, Steven J.

    2015-01-01

    Glutaredoxins (GRXs) are small glutathione dependent oxidoreductases that belong to the Thioredoxin (TRX) superfamily and catalyze the reduction of disulfide bonds of their substrate proteins. Plant GRXs include three different groups based on the motif sequence, namely CPYC, CGFS, and CC-type proteins. The rice CC-type proteins, OsGRX6 was identified during the screening for genes whose expression changes depending on the level of available nitrate. Overexpression of OsGRX6 in rice displayed a semi-dwarf phenotype. The OsGRX6 overexpressors contain a higher nitrogen content than the wild type, indicating that OsGRX6 plays a role in homeostatic regulation of nitrogen use. Consistent with this, OsGRX6 overexpressors displayed delayed chlorophyll degradation and senescence compared to the wild type plants. To examine if the growth defect of these transgenic lines attribute to disturbed plant hormone actions, plant hormone levels were measured. The levels of two cytokinins (CKs), 2-isopentenyladenine and trans-zeatin, and gibberellin A1 (GA1) were increased in these lines. We also found that these transgenic lines were less sensitive to exogenously applied GA, suggesting that the increase in GA1 is a result of the feedback regulation. These data suggest that OsGRX6 affects hormone signaling and nitrogen status in rice plants. PMID:26579177

  7. Abiotic Stresses Antagonize the Rice Defence Pathway through the Tyrosine-Dephosphorylation of OsMPK6

    PubMed Central

    Kishi-Kaboshi, Mitsuko; Matsushita, Akane; Jiang, Chang-Jie; Goto, Shingo; Takahashi, Akira; Hirochika, Hirohiko; Takatsuji, Hiroshi

    2015-01-01

    Plants, as sessile organisms, survive environmental changes by prioritizing their responses to the most life-threatening stress by allocating limited resources. Previous studies showed that pathogen resistance was suppressed under abiotic stresses. Here, we show the mechanism underlying this phenomenon. Phosphorylation of WRKY45, the central transcription factor in salicylic-acid (SA)-signalling-dependent pathogen defence in rice, via the OsMKK10-2–OsMPK6 cascade, was required to fully activate WRKY45. The activation of WRKY45 by benzothiadiazole (BTH) was reduced under low temperature and high salinity, probably through abscisic acid (ABA) signalling. An ABA treatment dephosphorylated/inactivated OsMPK6 via protein tyrosine phosphatases, OsPTP1/2, leading to the impaired activation of WRKY45 and a reduction in Magnaporthe oryzae resistance, even after BTH treatment. BTH induced a strong M. oryzae resistance in OsPTP1/2 knockdown rice, even under cold and high salinity, indicating that OsPTP1/2 is the node of SA-ABA signalling crosstalk and its down-regulation makes rice disease resistant, even under abiotic stresses. These results points to one of the directions to further improve crops by managing the tradeoffs between different stress responses of plants. PMID:26485146

  8. Abiotic Stresses Antagonize the Rice Defence Pathway through the Tyrosine-Dephosphorylation of OsMPK6.

    PubMed

    Ueno, Yoshihisa; Yoshida, Riichiro; Kishi-Kaboshi, Mitsuko; Matsushita, Akane; Jiang, Chang-Jie; Goto, Shingo; Takahashi, Akira; Hirochika, Hirohiko; Takatsuji, Hiroshi

    2015-10-01

    Plants, as sessile organisms, survive environmental changes by prioritizing their responses to the most life-threatening stress by allocating limited resources. Previous studies showed that pathogen resistance was suppressed under abiotic stresses. Here, we show the mechanism underlying this phenomenon. Phosphorylation of WRKY45, the central transcription factor in salicylic-acid (SA)-signalling-dependent pathogen defence in rice, via the OsMKK10-2-OsMPK6 cascade, was required to fully activate WRKY45. The activation of WRKY45 by benzothiadiazole (BTH) was reduced under low temperature and high salinity, probably through abscisic acid (ABA) signalling. An ABA treatment dephosphorylated/inactivated OsMPK6 via protein tyrosine phosphatases, OsPTP1/2, leading to the impaired activation of WRKY45 and a reduction in Magnaporthe oryzae resistance, even after BTH treatment. BTH induced a strong M. oryzae resistance in OsPTP1/2 knockdown rice, even under cold and high salinity, indicating that OsPTP1/2 is the node of SA-ABA signalling crosstalk and its down-regulation makes rice disease resistant, even under abiotic stresses. These results points to one of the directions to further improve crops by managing the tradeoffs between different stress responses of plants.

  9. OsSGL, a novel pleiotropic stress-related gene enhances grain length and yield in rice

    PubMed Central

    Wang, Manling; Lu, Xuedan; Xu, Guoyun; Yin, Xuming; Cui, Yanchun; Huang, Lifang; Rocha, Pedro S. C. F.; Xia, Xinjie

    2016-01-01

    Abiotic stress seriously affects the yield of rice (Oryza sativa L.). Grain yield in rice is multiplicatively determined by the number of panicles, number of grains per panicle, and grain weight. Here, we describe the molecular and functional characterization of STRESS_tolerance and GRAIN_LENGTH (OsSGL), a rice gene strongly up-regulated by a wide spectrum of abiotic stresses. OsSGL encodes a putative member of the DUF1645 protein family of unknown function. Overexpression of OsSGL significantly altered certain development processes greatly and positively affecting an array of traits in transgenic rice plants, including increased grain length, grain weight and grain number per panicle, resulting in a significant increase in yield. Microscopical analysis showed that the enhanced OsSGL expression promoted cell division and grain filling. Microarray and quantitative real-time PCR (qRT-PCR) analyses revealed that a large number of genes involved in stress-response, cell cycle and cytokinin signaling processes were induced or suppressed in OsSGL-overexpressing plants. Together, our results suggest that OsSGL may regulate stress-tolerance and cell growth by acting via a cytokinin signaling pathway. This study not only contributes to our understanding of the underlying mechanism regulating rice stress-tolerance and grain length, but also provides a strategy for tailor-made crop yield improvement. PMID:27917884

  10. Re-Os age of non-mineralized black shale from the Kupferschiefer, Poland, and implications for metal enrichment

    NASA Astrophysics Data System (ADS)

    Pašava, Jan; Oszczepalski, Slawomir; Du, Andao

    2010-02-01

    Six samples of non-mineralized black shale from a Kupferschiefer section in the northern part of the Polish Zechstein Basin (Zdrada IG-8 drill hole: 1026.16-1026.90 m) were studied for Re-Os isotopes and selected major and trace elements. These black shales, averaging 5.82 wt.% Corg and 1.69 wt.% Stot, display very low base metal values (up to 106 ppb Cu, 792 ppb Pb, and 144 ppb Zn) and have abundances of 64-1376 ppb Re and 0.37-1.25 ppb Os, with a 187Os/188Os ratio of 6.95-22.5. The regression of all Re-Os data yields an age of 247 ± 20 Ma, which is within the range of uncertainties of previous Rb-Sr and K-Ar geochronological studies. The scatter in the Re-Os data can be explained in terms of fluctuations in sedimentary conditions, i.e., restricted basin with terrestrial influence.

  11. Antibacterial Activity of Elephant Garlic and Its Effect against U2OS Human Osteosarcoma Cells

    PubMed Central

    Huang, Zehao; Ren, Jianwu

    2013-01-01

    Objective(s): The present study was designed to investigate the antibacterial function and pharmacological effect of elephant garlic (Allium ampeloprasum var. ampeloprasum) on U2OS human osteosarcoma cells. Materials and Methods: Seven kinds of bacteria were reconstituted, inoculated and tested in this research to evaluate elephant garlic antibacterial activity. By the means of FACS analysis, cell proliferation assay, confocal laser scanning microscopy and Transwell migration assays, the effect of elephant garlic against U2OS human osteosarcoma cells was unveiled. Rerults: The antimicrobial activity of elephant garlic was stronger than ampicillin when used against Escherichia coli, Bacillus subtilis, Bacillus thuringiensis, Staphylococcus actinomycetes, and gray actinomycetes. Even at a very low concentration (12.5%), elephant garlic still had an antibacterial effect on common bacteria E. coli and S. aureus. The G0/G1 ratio of elephant garlic treated group cells increased while S phase decreased. Elephant garlic extract inhibited the growth of human osteosarcoma cells, U2OS, through preventing the transition from G1 phase to S phase. It reduced osteosarcoma cell, U2OS, invasion ability and significantly increased the proportion of apoptosis. It significantly affected the cytoskeleton generation. Conclusion: Elephant garlic exhibits antibacterial property and has an inhibitory effect on osteosarcoma cells (U2OS) proliferation and cell activity, suggesting the mechanism of its anticancer effects on U2OS human osteosarcoma cells. PMID:24379966

  12. OsMADS1 Represses microRNA172 in Elongation of Palea/Lemma Development in Rice

    PubMed Central

    Dai, Zhengyan; Wang, Jiang; Zhu, Mulan; Miao, Xuexia; Shi, Zhenying

    2016-01-01

    Specification of floral organ identity is critical for the establishment of floral morphology and inflorescence architecture. Although multiple genes are involved in the regulation of floral organogenesis, our understanding of the underlying regulating network is still fragmentary. MADs-box genes are principle members in the ABCDE model that characterized floral organs. OsMADS1 specifies the determinacy of spikelet meristem and lemma/palea identity in rice. However, the pathway through which OsMADS1 regulates floral organs remains elusive; here, we identified the microRNA172 (miR172) family as possible regulators downstream of OsMADS1. Genetic study revealed that overexpression of each miR172 gene resulted in elongated lemma/palea and indeterminacy of the floret, which resemble the phenotype of osmads1 mutant. On the contrary, overexpression of each target APETALA2 (AP2) genes resulted in shortened palea/lemma. Expression level and specificity of miR172 was greatly influenced by OsMADS1, as revealed by Northern blot analysis and In situ hybridization. Genetically, AP2-3 and AP2-2 over expression rescued the elongation and inconsistent development of the lemma/palea in OsMADS1RNAi transgenic plants. Our results suggested that in rice, OsMADS1 and miR172s/AP2s formed a regulatory network involved in floral organ development, particularly the elongation of the lemma and the palea. PMID:28066457

  13. Genome-Wide Identification, Phylogenetic and Co-Expression Analysis of OsSET Gene Family in Rice

    PubMed Central

    Lu, Zhanhua; Huang, Xiaolong; Ouyang, Yidan; Yao, Jialing

    2013-01-01

    Background SET domain is responsible for the catalytic activity of histone lysine methyltransferases (HKMTs) during developmental process. Histone lysine methylation plays a crucial and diverse regulatory function in chromatin organization and genome function. Although several SET genes have been identified and characterized in plants, the understanding of OsSET gene family in rice is still very limited. Methodology/Principal Findings In this study, a systematic analysis was performed and revealed the presence of at least 43 SET genes in rice genome. Phylogenetic and structural analysis grouped SET proteins into five classes, and supposed that the domains out of SET domain were significant for the specific of histone lysine methylation, as well as the recognition of methylated histone lysine. Based on the global microarray, gene expression profile revealed that the transcripts of OsSET genes were accumulated differentially during vegetative and reproductive developmental stages and preferentially up or down-regulated in different tissues. Cis-elements identification, co-expression analysis and GO analysis of expression correlation of 12 OsSET genes suggested that OsSET genes might be involved in cell cycle regulation and feedback. Conclusions/Significance This study will facilitate further studies on OsSET family and provide useful clues for functional validation of OsSETs. PMID:23762371

  14. Magnetic structure of the quasi-one-dimensional La3OsO7 as determined by neutron powder diffraction

    DOE PAGES

    Morrow, Ryan; Susner, Michael A.; Sumption, Michael D.; ...

    2015-10-05

    Insulating 5d3 La3OsO7 and the isostructural hole-doped analog La2.8Ca0.2OsO7 that feature pseudo-one-dimensional zigzag chains of corner-sharing OsO6 octahedra were synthesized and their magnetic and electrical transport properties characterized. Both of these compounds are insulating antiferromagnets. Moreover, for long range magnetic order between the antiferromagnetic chains we determined with a propagation vector k = 1/2,1/2,1 and TN = 45 and 33 K the parent and doped materials. An Os5+ moment of 1.7(1)μB for La3OsO7 and 1.2(2)μB for La2.8Ca0.2OsO7 is refined. The long range magnetic structure is compared to the isostructural compounds La3RuO7 and La3MoO7, both of which adopt different magnetic structures.

  15. Retention of OsNMD3 in the cytoplasm disturbs protein synthesis efficiency and affects plant development in rice.

    PubMed

    Shi, Yanyun; Liu, Xiangling; Li, Rui; Gao, Yaping; Xu, Zuopeng; Zhang, Baocai; Zhou, Yihua

    2014-07-01

    The ribosome is the basic machinery for translation, and biogenesis of ribosomes involves many coordinated events. However, knowledge about ribosomal dynamics in higher plants is very limited. This study chose a highly conserved trans-factor, the 60S ribosomal subunit nuclear export adaptor NMD3, to characterize the mechanism of ribosome biogenesis in the monocot plant Oryza sativa (rice). O. sativa NMD3 (OsNMD3) shares all the common motifs and shuttles between the nucleus and cytoplasm via CRM1/XPO1. A dominant negative form of OsNMD3 with a truncated nuclear localization sequence (OsNMD3(ΔNLS)) was retained in the cytoplasm, consequently interfering with the release of OsNMD3 from pre-60S particles and disturbing the assembly of ribosome subunits. Analyses of the transactivation activity and cellulose biosynthesis level revealed low protein synthesis efficiency in the transgenic plants compared with the wild-type plants. Pharmaceutical treatments demonstrated structural alterations in ribosomes in the transgenic plants. Moreover, global expression profiles of the wild-type and transgenic plants were investigated using the Illumina RNA sequencing approach. These expression profiles suggested that overexpression of OsNMD3(ΔNLS) affected ribosome biogenesis and certain basic pathways, leading to pleiotropic abnormalities in plant growth. Taken together, these results strongly suggest that OsNMD3 is important for ribosome assembly and the maintenance of normal protein synthesis efficiency.

  16. Redox electrodeposition polymers: adaptation of the redox potential of polymer-bound Os complexes for bioanalytical applications.

    PubMed

    Guschin, Dmitrii A; Castillo, John; Dimcheva, Nina; Schuhmann, Wolfgang

    2010-10-01

    The design of polymers carrying suitable ligands for coordinating Os complexes in ligand exchange reactions against labile chloro ligands is a strategy for the synthesis of redox polymers with bound Os centers which exhibit a wide variation in their redox potential. This strategy is applied to polymers with an additional variation of the properties of the polymer backbone with respect to pH-dependent solubility, monomer composition, hydrophilicity etc. A library of Os-complex-modified electrodeposition polymers was synthesized and initially tested with respect to their electron-transfer ability in combination with enzymes such as glucose oxidase, cellobiose dehydrogenase, and PQQ-dependent glucose dehydrogenase entrapped during the pH-induced deposition process. The different polymer-bound Os complexes in a library containing 50 different redox polymers allowed the statistical evaluation of the impact of an individual ligand to the overall redox potential of an Os complex. Using a simple linear regression algorithm prediction of the redox potential of Os complexes becomes feasible. Thus, a redox polymer can now be designed to optimally interact in electron-transfer reactions with a selected enzyme.

  17. Evidence for crustal contamination in intra-continental OIB-like basalts from West Qinling, central China: A Re-Os perspective

    NASA Astrophysics Data System (ADS)

    Li, Xiaowei; Li, Jie; Bader, Thomas; Mo, Xuanxue; Scheltens, Mark; Chen, Zhenyu; Xu, Jifeng; Yu, Xuehui; Huang, Xiongfei

    2015-02-01

    The magnitude of crustal contamination in intra-continental OIB-like basalts is commonly difficult to assess in terms of major, trace-element and Pb-Sr-Nd isotopes. However, the Re-Os isotope system is a very sensitive tracer of the crustal component during formation of basaltic rocks. Here we report new Sr-Nd-Pb-Os geochemical and isotopic data from the Cretaceous Duofutun Volcanic Rocks (DVRs) of West Qinling, central China. The DVRs exhibit low Os abundances (4.46-42.02 ppt) with Re abundances ranging from 45.58 to 812.98 ppt, variably high Re/Os (3-126), and high initial 187Os/188Os ratios (0.2112-0.6784). We propose that the degree of partial melting is responsible for the first-order control on the variation of Os concentrations. Even the least radiogenic sample still possesses a higher initial 187Os/188Os ratio than the primitive upper mantle, implying a non-negligible contribution from high Re/Os and 187Os/188Os reservoir(s). Both the crust and pyroxenite-rich mantle are reliable candidates, but the latter cannot be reconciled with the Os mass balance between pyroxenite and ambient peridotite. Hence, we contend that these rocks were contaminated by crustal materials en route to the surface. Assimilation/fractional crystallization modeling manifests the observed isotopic variations can be produced by minor assimilation of the Proterozoic mafic lower crust. In addition, the intra-continental OIB-like basalts show a relatively wider range of 187Os/188Os ratios in comparison with MORB and OIB, confirming the continental crust can have a higher concentration of radioactive Os, which is induced by time-integrated growth.

  18. The effect of chemical pressure on the structure and properties of A2CrOsO6 (A=Sr, Ca) ferrimagnetic double perovskite

    NASA Astrophysics Data System (ADS)

    Morrow, Ryan; Soliz, Jennifer R.; Hauser, Adam J.; Gallagher, James C.; Susner, Michael A.; Sumption, Michael D.; Aczel, Adam A.; Yan, Jiaqiang; Yang, Fengyuan; Woodward, Patrick M.

    2016-06-01

    The ordered double perovskites Sr2CrOsO6 and Ca2CrOsO6 have been synthesized and characterized with neutron powder diffraction, electrical transport measurements, and high field magnetization experiments. As reported previously Sr2CrOsO6 crystallizes with R 3 bar symmetry due to a-a-a- octahedral tilting. A decrease in the tolerance factor leads to a-a-b+ octahedral tilting and P21/n space group symmetry for Ca2CrOsO6. Both materials are found to be ferrimagnetic insulators with saturation magnetizations near 0.2 μB. Sr2CrOsO6 orders at 660 K while Ca2CrOsO6 orders at 490 K. Variable temperature magnetization measurements suggest that the magnetization of the Cr3+ and Os3+ sublattices have different temperature dependences in Sr2CrOsO6. This leads to a non-monotonic temperature evolution of the magnetic moment. Similar behavior is not seen in Ca2CrOsO6. Both compounds have similar levels of Os/Cr antisite disorder, with order parameters of η=80.2(4)% for Sr2CrOsO6 and η=76.2(5)% for Ca2CrOsO6, where η=2θ-1 and θ is the occupancy of the osmium ion on the osmium-rich Wyckoff site.

  19. Overexpression of OsMYC2 Results in the Up-Regulation of Early JA-Rresponsive Genes and Bacterial Blight Resistance in Rice.

    PubMed

    Uji, Yuya; Taniguchi, Shiduku; Tamaoki, Daisuke; Shishido, Hodaka; Akimitsu, Kazuya; Gomi, Kenji

    2016-09-01

    JASMONATE ZIM-domain (JAZ) proteins act as transcriptional repressors of jasmonic acid (JA) responses and play a crucial role in the regulation of host immunity in plants. Here, we report that OsMYC2, a JAZ-interacting transcription factor in rice (Oryza sativa L.), plays an important role in the resistance response against rice bacterial blight, which is one of the most serious diseases in rice, caused by Xanthomonas oryzae pv. oryzae (Xoo). The results showed that OsMYC2 interacted with some OsJAZ proteins in a JAZ-interacting domain (JID)-dependent manner. The up-regulation of OsMYC2 in response to JA was regulated by OsJAZ8. Transgenic rice plants overexpressing OsMYC2 exhibited a JA-hypersensitive phenotype and were more resistant to Xoo. A large-scale microarray analysis revealed that OsMYC2 up-regulated OsJAZ10 as well as many other defense-related genes. OsMYC2 selectively bound to the G-box-like motif of the OsJAZ10 promoter in vivo and regulated the expression of early JA-responsive genes, but not of late JA-responsive genes. The nuclear localization of OsMYC2 depended on a nuclear localization signal within JID. Overall, we conclude that OsMYC2 acts as a positive regulator of early JA signals in the JA-induced resistance against Xoo in rice.

  20. Behaviors of transmutation elements Re and Os and their effects on energetics and clustering of vacancy and self-interstitial atoms in W

    NASA Astrophysics Data System (ADS)

    Li, Yu-Hao; Zhou, Hong-Bo; Jin, Shuo; Zhang, Ying; Deng, Huiqiu; Lu, Guang-Hong

    2017-04-01

    We investigate the behaviors of rhenium (Re) and osmium (Os) and their interactions with point defects in tungsten (W) using a first-principles method. We show that Re atoms are energetically favorable to disperse separately in bulk W due to the Re–Re repulsive interaction. Despite the attractive interaction between Os atoms, there is still a large activation energy barrier of 1.10 eV at the critical number of 10 for the formation of Os clusters in bulk W based on the results of the total nucleation free energy change. Interestingly, the presence of vacancy can significantly reduce the total nucleation free energy change of Re/Os clusters, suggesting that vacancy can facilitate the nucleation of Re/Os in W. Re/Os in turn has an effect on the stability of the vacancy clusters (V n ) in W, especially for small vacancy clusters. A single Re/Os atom can raise the total binding energies of V2 and V3 obviously, thus enhancing their formation. Further, we demonstrate that there is a strong attractive interaction between Re/Os and self-interstitial atoms (SIAs). Re/Os could increase the diffusion barrier of SIAs and decrease their rotation barrier, while the interstitial-mediated path may be the optimal diffusion path of Re/Os in W. Consequently, the synergistic effect between Re/Os and point defects plays a key role in Re/Os precipitation and the evolution of defects in irradiated W.

  1. Rice OsVAMP714, a membrane-trafficking protein localized to the chloroplast and vacuolar membrane, is involved in resistance to rice blast disease.

    PubMed

    Sugano, Shoji; Hayashi, Nagao; Kawagoe, Yasushi; Mochizuki, Susumu; Inoue, Haruhiko; Mori, Masaki; Nishizawa, Yoko; Jiang, Chang-Jie; Matsui, Minami; Takatsuji, Hiroshi

    2016-05-01

    Membrane trafficking plays pivotal roles in many cellular processes including plant immunity. Here, we report the characterization of OsVAMP714, an intracellular SNARE protein, focusing on its role in resistance to rice blast disease caused by the fungal pathogen Magnaporthe oryzae. Disease resistance tests using OsVAMP714 knockdown and overexpressing rice plants demonstrated the involvement of OsVAMP714 in blast resistance. The overexpression of OsVAMP7111, whose product is highly homologous to OsVAMP714, did not enhance blast resistance to rice, implying a potential specificity of OsVAMP714 to blast resistance. OsVAMP714 was localized to the chloroplast in mesophyll cells and to the cellular periphery in epidermal cells of transgenic rice plant leaves. We showed that chloroplast localization is critical for the normal OsVAMP714 functioning in blast resistance by analyzing the rice plants overexpressing OsVAMP714 mutants whose products did not localize in the chloroplast. We also found that OsVAMP714 was located in the vacuolar membrane surrounding the invasive hyphae of M. oryzae. Furthermore, we showed that OsVAMP714 overexpression promotes leaf sheath elongation and that the first 19 amino acids, which are highly conserved between animal and plant VAMP7 proteins, are crucial for normal rice plant growths. Our studies imply that the OsVAMP714-mediated trafficking pathway plays an important role in rice blast resistance as well as in the vegetative growth of rice.

  2. Ab initio calculations of mechanical properties of bcc W-Re-Os random alloys: effects of transmutation of W

    NASA Astrophysics Data System (ADS)

    Li, Xiaojie; Schönecker, Stephan; Li, Ruihuan; Li, Xiaoqing; Wang, Yuanyuan; Zhao, Jijun; Johansson, Börje; Vitos, Levente

    2016-07-01

    To examine the effect of neutron transmutation on tungsten as the first wall material of fusion reactors, the elastic properties of W1-x-y  Re x  Os y (0  ⩽  x, y  ⩽  6%) random alloys in body centered cubic (bcc) structure are investigated systematically using the all-electron exact muffin-tin orbitals (EMTO) method in combination with the coherent-potential approximation (CPA). The calculated lattice constant and elastic properties of pure W are consistent with available experiments. Both Os and Re additions reduce the lattice constant and increase the bulk modulus of W, with Os having the stronger effect. The polycrystalline shear modulus, Young’s modulus and the Debye temperature increase (decrease) with the addition of Re (Os). Except for C 11, the other elastic parameters including C 12, C 44, Cauchy pressure, Poisson ratio, B/G, increase as a function of Re and Os concentration. The variations of the latter three parameters and the trend in the ratio of cleavage energy to shear modulus for the most dominant slip system indicate that the ductility of the alloy enhances with increasing Re and Os content. The calculated elastic anisotropy of bcc W slightly increases with the concentration of both alloying elements. The estimated melting temperatures of the W-Re-Os alloy suggest that Re or Os addition will reduce the melting temperature of pure W solid. The classical Labusch-Nabarro model for solid-solution hardening predicts larger strengthening effects in W1-y  Os y than in W1-x  Re x . A strong correlation between C‧ and the fcc-bcc structural energy difference for W1-x-y  Re x  Os y is revealed demonstrating that canonical band structure dictates the alloying effect on C‧. The structural energy difference is exploited to estimate the alloying effect on the ideal tensile strength in the [0 0 1] direction.

  3. Ab initio calculations of mechanical properties of bcc W-Re-Os random alloys: effects of transmutation of W.

    PubMed

    Li, Xiaojie; Schönecker, Stephan; Li, Ruihuan; Li, Xiaoqing; Wang, Yuanyuan; Zhao, Jijun; Johansson, Börje; Vitos, Levente

    2016-06-03

    To examine the effect of neutron transmutation on tungsten as the first wall material of fusion reactors, the elastic properties of W1-x-y  Re x  Os y (0  ⩽  x, y  ⩽  6%) random alloys in body centered cubic (bcc) structure are investigated systematically using the all-electron exact muffin-tin orbitals (EMTO) method in combination with the coherent-potential approximation (CPA). The calculated lattice constant and elastic properties of pure W are consistent with available experiments. Both Os and Re additions reduce the lattice constant and increase the bulk modulus of W, with Os having the stronger effect. The polycrystalline shear modulus, Young's modulus and the Debye temperature increase (decrease) with the addition of Re (Os). Except for C 11, the other elastic parameters including C 12, C 44, Cauchy pressure, Poisson ratio, B/G, increase as a function of Re and Os concentration. The variations of the latter three parameters and the trend in the ratio of cleavage energy to shear modulus for the most dominant slip system indicate that the ductility of the alloy enhances with increasing Re and Os content. The calculated elastic anisotropy of bcc W slightly increases with the concentration of both alloying elements. The estimated melting temperatures of the W-Re-Os alloy suggest that Re or Os addition will reduce the melting temperature of pure W solid. The classical Labusch-Nabarro model for solid-solution hardening predicts larger strengthening effects in W1-y  Os y than in W1-x  Re x . A strong correlation between C' and the fcc-bcc structural energy difference for W1-x-y  Re x  Os y is revealed demonstrating that canonical band structure dictates the alloying effect on C'. The structural energy difference is exploited to estimate the alloying effect on the ideal tensile strength in the [0 0 1] direction.

  4. Thermal Cycle Reliability of PBGA/CCGA 717 I/Os

    NASA Technical Reports Server (NTRS)

    Ghaffarian, Reza

    2006-01-01

    Status of thermal cycle test results for a nonfunctional daisy-chained peripheral ceramic column grid array (CCGA) and its plastic ball grid array (PBGA) version. both having 560 I/Os. were presented in last year's conference. Test results included environmental data for three different thermal cycle regimes (-55 C/125 C, -55 C/100 C, and -50 C /75 C). Update information on these - especially failure type for assemblies with high and low solder volumes-were presented. The thermal cycle test procedure followed those recommended IPC-9701 for tin-lead solder joint assemblies. Revision A of this specification covers guideline thermal cycle requirements for Pb-free solder joints. Some background information discussed during release of this specification with its current guideline recommendations were also presented. In a recent reliability investigation a fully populated CCGA with 717 I/Os was also considered for assembly reliability. evaluation. The functional package is a field-programmable gate array that has much higher processing power than its previous version. This new package is smaller in dimension, has no interposer, and has a thinner column wrapped with copper for reliability improvement. This paper will also present thermal cycle test results for this package assembly and its plastic version with 728 I/Os. both of which were exposed to three different cycle regimes. Two cycle profiles were those specified by IPC- 9701A for tin-lead, i.e. -55 to 100 C and -55 to 125 C and one was a cycle profile specified by Mil-Std-883, i.e.. -65 C/150 C which is generally used for ceramic hybrid packages. Per IPC-9701 A, test vehicles were built using daisy chain packages and were continuously monitored. The effects of many process and assembly variables-including corner staking commonly used for improving resistance to mechanical loading such as drop and vibration loads--were also considered as part of the test matrix. Optical photomicrographs were taken at various thermal

  5. PREVENCION DE VIH PARA MUJERES HISPANAS DE 50 AÑOS Y MÁS

    PubMed Central

    Villegas, N.; Cianelli, R.; Ferrer, L.; Kaelber, L.; Peragallo, N.; Yaya, Alexandra O.

    2012-01-01

    Introducción Las mujeres Hispanas de 50 años y más (MHC) son una minoría en Estados Unidos que está a elevado riesgo de adquirir VIH y son el grupo menos estudiado en lo que respecta a salud, características sociales y de comportamiento sexual. Objetivo Investigar los factores que incrementan el riesgo de VIH en las MHC con el propósito de desarrollar o adaptar una intervención apropiada para la “edad y la cultura "de este grupo de mujeres. Metodología Estudio descriptivo de corte transversal con una muestra de 50 MHC, sexualmente activas y que residían en Miami, Florida, Estados Unidos. Se utilizó un cuestionario estructurado administrado por entrevistadores entrenados y bilingües (inglés/español). Las participantes fueron reclutadas en diferentes lugares en el Sur de Florida. Para el análisis de los datos se utilizó estadística descriptiva, tanto medidas de tendencia central como medidas de dispersión. Resultados La edad promedio de las MHC fue de 55,7 ± 6 años (rango 50–76 años). Todas las MHC estaban en la menopausia. Prevención del VIH Las MHC reportaron niveles medios de conocimientos sobre VIH y comunicación con la pareja. En la muestra se reportó la presencia de síntomas depresivos, violencia en la pareja, actitudes negativas hacia las personas viviendo con VIH y baja percepción de riesgo de adquirir VIH. Las MHC mencionaron necesidades de aprendizaje en tópicos relacionados con prevención de VIH y cambios de la edad. Conclusión Las MHC están a riesgo de adquirir VIH y tienen necesidades especiales en términos de educación sobre prevención de VIH. PMID:25242862

  6. Geodynamics of magmatic Cu-Ni-PGE sulfide deposits: new insights from the Re-Os isotope system

    USGS Publications Warehouse

    Lambert, D.D.; Foster, J.G.; Frick, L.R.; Ripley, E.M.; Zientek, M.L.

    1998-01-01

    In this study, we reassess crustal contamination and sulfide ore-forming processes in some of the largest magmatic ore deposits, using published Re-Os isotope data and a modeling methodology that incorporates the R factor, defined as the effective mass of silicate magma with which a given mass of sulfide magma has equilibrated, in an Re-Os isotope mixing equation. We show that there is less disparity between conclusions based on Re-Os isotope data compared to other isotopic systems if the R factor is considered, Komatiite-associated Ni sulfide ore systems typically have high Os concentrations, low Re/Os ratios, and near-chondritic initial Os isotope compositions. For magmatic sulfide ores that are interpreted to have experienced relatively low R factors (2,000). Sulfide saturation in these ore systems may, therefore, have been achieved via changes in intensive parameters of the komatiite lavas (cooling or decompression) or changes in compositional parameters transparent to the Re-Os isotope system (e.g., fo2/fs2/fH2O)- Basalt-gabbro-associated Cu-Ni sulfide ore systems at Duluth, Sudbury, and Stillwater are quite distinct from those at Kambalda by having comparatively low Os concentrations, high Re/Os ratios, and high initial Os isotope compositions, These chemical and isotopic characteristics are indicative of significant interactions between their parental basaltic magmas and old crust because there are no known mantle reservoirs with such extreme geocheinical characteristics. Our modeling suggests that for Cu-Ni sulfide ores at Duluth, Sudbury, and Stillwater to maintain the observed high initial Os isotope compositions inherited from a crustal contaminant, R factors for these systems must have been low (< 10,000), consistent with their low metal concentrations. Thus, we interpret this style of base metal sulfide mineralization to be derived from crustally contaminated but less dynamic magmatic systems that did not permit extensive equilibration of sulfide magma

  7. 187Os/188Os in Spinel Peridotites from Borée, Massif Central, France: Seeing through the Effects of Melt Infiltration in the Sub-continental Lithospheric Mantle

    NASA Astrophysics Data System (ADS)

    Barnett, C. J.; Harvey, J.

    2015-12-01

    The Re-Os isotope system can be used to model the timing of melt extraction in peridotites, although secondary metasomatic processes can obscure primary melt depletion signatures, implying that bulk-rock Os model ages should be treated with caution.1Spinel peridotites from the volcanic Maar de Borée (French Massif Central) have equigranular to protogranular and occasionally poikilitic textures. Their bulk-rock chemistry are consistent with moderate degrees of partial melting, but elevated incompatible trace element ratios (e.g. La/YbN) are indicative of subsequent secondary processes. Petrographic observation reveals no infiltration of host basalt, but melt infiltration unrelated to the host basalt has occurred, most likely within the sub-continental lithospheric mantle prior to entrainment as xenoliths. The peridotites have a mean [Os] concentration of 2.35 ng g-1 and 187Os/188Os values from 0.12081 ± 16 to 0.12639 ± 14 (cf. PUM = 0.1296 ± 00082), with rhenium depletion model ages (TRD) ranging from 0.48 to 1.30 Ga. Silicate melt contains up to 2 orders of magnitude less Os than peridotites3 but the 187Os/188Os of melt infiltrated peridotite can be skewed by the precipitation of immiscible sulfide when an infiltrating melt reaches S-saturation4. The Borée peridotites retain an unradiogenic Os-isotope signature despite silicate melt infiltration; this may be due to primary base metal sulfides enclosed in silicate minerals and therefore protected from interaction with infiltrating melts. TRD of enclosed sulphides should therefore be able to 'see through' any secondary metasomatic events and reveal melt depletion ages significantly older than those obtained from bulk-rock analyses (cf. 4). 1. Rudnick & Walker (2009) Lithos 112S, 1083-1095. 2. Meisel et al. (2001) Geochim Cosmochim Ac 65, 1311-1323. 3. Day, J.M.D. (2013) Chem Geol 341, 50-74. 4. Harvey et al. (2010) Geochim Cosmochim Acta 74, 293-320.

  8. A novel sample decomposition technique at atmospheric pressure for the determination of Os abundances in iron meteorites using isotope dilution inductively coupled plasma-mass spectrometry.

    PubMed

    Hattori, M; Hirata, T

    2001-06-01

    A safe and reliable analytical technique for the determination of Os abundances in ten iron meteorites of various chemical groups was developed using isotope dilution inductively coupled plasma-mass spectrometry coupled with a sample decomposition technique. A major advantage of the sample decomposition technique developed here is that the pressure inside the reaction flask is not increased through the decomposition reaction because the flask is a fully opened system, obviating the risk of explosion of the glass apparatus. Another advantage is that there is no restriction in the sample size being decomposed. In this study, about 2 g of metallic sample were decomposed safely, and this sample size, > 10 times larger than that typically used for the Carius tube technique, allows one to obtain more reliable Os data for heterogeneous samples. The metallic samples were decomposed in a glass flask purged with Ar. Since the O2 was purged from the reaction flask, Os was not oxidised to volatile OsO4, thereby preventing significant evaporation loss of Os. The typical recovery of Os throughout the sample decomposition and separation processes was > 80%, and the total Os blank through the decomposition of a 1 g amount of sample was less than 20 pg. Os abundances were determined by means of stable isotope dilution mass spectrometry using a 190Os-enriched isotopic tracer. Except for Sikhote-Alin, the measured Os abundances in almost all the iron meteorites exhibited a good agreement with the previously published Os abundance data, within the analytical uncertainty achieved in this study (2-5%). For the Sikhote-Alin meteorite, on the basis of a better correlation between Os and Ir abundances, we believe that our Os abundance data should be more reliable. The Os abundance data obtained in this work clearly demonstrated the suitability of the newly developed sample decomposition procedure for low level Os determinations.

  9. Deregulation of the OsmiR160 Target Gene OsARF18 Causes Growth and Developmental Defects with an Alteration of Auxin Signaling in Rice

    PubMed Central

    Huang, Jian; Li, Zhiyong; Zhao, Dazhong

    2016-01-01

    MicroRNAs (miRNAs) control gene expression as key negative regulators at the post-transcriptional level. MiR160 plays a pivotal role in Arabidopsis growth and development through repressing expression of its target AUXIN RESPONSE FACTOR (ARF) genes; however, the function of miR160 in monocots remains elusive. In this study, we found that the mature rice miR160 (OsmiR160) was mainly derived from OsMIR160a and OsMIR160b genes. Among four potential OsmiR160 target OsARF genes, the OsARF18 transcript was cleaved at the OsmiR160 target site. Rice transgenic plants (named mOsARF18) expressing an OsmiR160-resistant version of OsARF18 exhibited pleiotropic defects in growth and development, including dwarf stature, rolled leaves, and small seeds. mOsARF18 leaves were abnormal in bulliform cell differentiation and epidermal cell division. Starch accumulation in mOsARF18 seeds was also reduced. Moreover, auxin induced expression of OsMIR160a, OsMIR160b, and OsARF18, whereas expression of OsMIR160a and OsMIR160b as well as genes involved in auxin signaling was altered in mOsARF18 plants. Our results show that negative regulation of OsARF18 expression by OsmiR160 is critical for rice growth and development via affecting auxin signaling, which will advance future studies on the molecular mechanism by which miR160 fine-tunes auxin signaling in plants. PMID:27444058

  10. Rice cyclophilin OsCYP18-2 is translocated to the nucleus by an interaction with SKIP and enhances drought tolerance in rice and Arabidopsis.

    PubMed

    Lee, Sang Sook; Park, Hyun Ji; Yoon, Dae Hwa; Kim, Beom-Gi; Ahn, Jun Cheul; Luan, Sheng; Cho, Hye Sun

    2015-10-01

    Cyclophilin 18-2 (CYP18-2) genes, homologues of human peptidyl-prolyl isomerase-like 1 (PPiL1), are conserved across multicellular organisms and Schizosaccharomyces pombe. Although PPiL1 is known to interact with ski-interacting protein (SKIP), a transcriptional co-regulator and spliceosomal component, there have been no functional analyses of PPiL1 homologues in plants. Rice cyclophilin 18-2 (OsCYP18-2) bound directly to amino acids 56-95 of OsSKIP and its binding was independent of cyclosporin A, a cyclophilin-binding drug. Moreover, OsCYP18-2 exhibited PPIase activity regardless of its interaction with OsSKIP. Therefore, the binding site for OsCYP18-2's interaction with SKIP was distinct from the PPIase active site. OsCYP18-2's interaction with SKIP full-length protein enabled OsCYP18-2's translocation from the cytoplasm into the nucleus and AtSKIP interacted in planta with both AtCYP18-2 and OsCYP18-2. Drought and salt stress induced similar expression of OsCYP18-2 and OsSKIP. Overexpression of OsCYP18-2 in transgenic rice and Arabidopsis thaliana plants enhanced drought tolerance and altered expression and pre-mRNA splicing patterns of stress-related genes in Arabidopsis under drought conditions. Furthermore, OsCYP18-2 caused transcriptional activation with/without OsSKIP in the GAL4 system of yeast; thus the OsSKIP-OsCYP18-2 interaction has an important role in the transcriptional and post-transcriptional regulation of stress-related genes and increases tolerance to drought stress.

  11. Rice aleurone layer specific OsNF-YB1 regulates grain filling and endosperm development by interacting with an ERF transcription factor

    PubMed Central

    Xu, Jing-Jing; Zhang, Xiao-Fan; Xue, Hong-Wei

    2016-01-01

    Grain yield and quality of rice mainly depend on grain filling and endosperm development. Here we report that a rice NUCLEAR FACTOR Y (NF-Y) transcription factor, OsNF-YB1, is specifically expressed in the aleurone layer of developing endosperm and regulates grain filling and endosperm development. Knockdown of OsNF-YB1 expression by RNAi significantly retarded grain filling, leading to small grains with chalky endosperm as well as altered starch quality. Whereas OsNF-YB1 shows subcellular localization in both the cytosol and the nucleus in roots, it was specifically targeted to the nucleus of aleurone layer cells, which was facilitated by interacting with OsNF-YC proteins preferentially expressed in the aleurone layer. RNA sequencing analysis revealed that genes related to membrane transport and ATP biosynthesis were enriched in the down-regulated category in OsNF-YB1 RNAi plants, which is consistent with the crucial role of OsNF-YB1 in rice grain filling and endosperm development. Identification of the genome-wide targets of OsNF-YB1 by ChIP sequencing showed that OsNF-YB1 directly regulates genes involved in the transport of nutrients such as sugar and amino acids. Interestingly, different from the binding sites reported for other NF-Y complexes, the GCC box, the binding motif of ERF transcription factors, was enriched in the binding peaks of OsNF-YB1. Indeed, further analyses confirmed the interaction of OsERF#115 with OsNF-YB1, and OsERF#115 directly binds to the GCC box. It is proposed that OsNF-YB1 specifically regulate the transcription of downstream genes during rice endosperm development by forming protein complexes consisting of OsNF-YB1, OsNF-YC and ERF, providing informative insights into the molecular functional mechanisms of the NF-Y factor. PMID:27803124

  12. The bifunctional plant receptor, OsCERK1, regulates both chitin-triggered immunity and arbuscular mycorrhizal symbiosis in rice.

    PubMed

    Miyata, Kana; Kozaki, Toshinori; Kouzai, Yusuke; Ozawa, Kenjirou; Ishii, Kazuo; Asamizu, Erika; Okabe, Yoshihiro; Umehara, Yosuke; Miyamoto, Ayano; Kobae, Yoshihiro; Akiyama, Kohki; Kaku, Hanae; Nishizawa, Yoko; Shibuya, Naoto; Nakagawa, Tomomi

    2014-11-01

    Plants are constantly exposed to threats from pathogenic microbes and thus developed an innate immune system to protect themselves. On the other hand, many plants also have the ability to establish endosymbiosis with beneficial microbes such as arbuscular mycorrhizal (AM) fungi or rhizobial bacteria, which improves the growth of host plants. How plants evolved these systems managing such opposite plant-microbe interactions is unclear. We show here that knockout (KO) mutants of OsCERK1, a rice receptor kinase essential for chitin signaling, were impaired not only for chitin-triggered defense responses but also for AM symbiosis, indicating the bifunctionality of OsCERK1 in defense and symbiosis. On the other hand, a KO mutant of OsCEBiP, which forms a receptor complex with OsCERK1 and is essential for chitin-triggered immunity, established mycorrhizal symbiosis normally. Therefore, OsCERK1 but not chitin-triggered immunity is required for AM symbiosis. Furthermore, experiments with chimeric receptors showed that the kinase domains of OsCERK1 and homologs from non-leguminous, mycorrhizal plants could trigger nodulation signaling in legume-rhizobium interactions as the kinase domain of Nod factor receptor1 (NFR1), which is essential for triggering the nodulation program in leguminous plants, did. Because leguminous plants are believed to have developed the rhizobial symbiosis on the basis of AM symbiosis, our results suggest that the symbiotic function of ancestral CERK1 in AM symbiosis enabled the molecular evolution to leguminous NFR1 and resulted in the establishment of legume-rhizobia symbiosis. These results also suggest that OsCERK1 and homologs serve as a molecular switch that activates defense or symbiotic responses depending on the infecting microbes.

  13. Synthesis of Oligosaccharides Derived from Lactulose (OsLu) Using Soluble and Immobilized Aspergillus oryzae β-Galactosidase.

    PubMed

    Cardelle-Cobas, Alejandra; Olano, Agustin; Irazoqui, Gabriela; Giacomini, Cecilia; Batista-Viera, Francisco; Corzo, Nieves; Corzo-Martínez, Marta

    2016-01-01

    β-Galactosidase from Aspergillus oryzae offers a high yield for the synthesis of oligosaccharides derived from lactulose (OsLu) by transgalactosylation. Oligosaccharides with degree of polymerization (DP) ≥ 3 have shown to possess higher in vitro bifidogenic effect than di- and tetrasaccharides. Thus, in this work, an optimization of reaction conditions affecting the specific selectivity of A. oryzae β-galactosidase for synthesis of OsLu has been carried out to enhance OsLu with DP ≥ 3 production. Assays with β-galactosidase immobilized onto a glutaraldehyde-agarose support were also carried out with the aim of making the process cost-effective and industrially viable. Optimal conditions with both soluble and immobilized enzyme for the synthesis of OsLu with DP ≥ 3 were 50 °C, pH 6.5, 450 g/L of lactulose, and 8 U/mL of enzyme, reaching yields of ca. 50% (w/v) of total OsLu and ca. 20% (w/v) of OsLu with DP 3, being 6'-galactosyl-lactulose the major one, after a short reaction time. Selective formation of disaccharides, however, was favored at 60 °C, pH 4.5, 450 g/L of lactulose and 8 U/mL of enzyme. Immobilization increased the enzymatic stability to temperature changes and allowed to reuse the enzyme. We can conclude that the use, under determined optimal conditions, of the A. oryzae β-galactosidase immobilized on a support of glutaraldehyde-agarose constitutes an efficient and cost-effective alternative to the use of soluble β-galactosidases for the synthesis of prebiotic OsLu mixtures.

  14. Synthesis of Oligosaccharides Derived from Lactulose (OsLu) Using Soluble and Immobilized Aspergillus oryzae β-Galactosidase

    PubMed Central

    Cardelle-Cobas, Alejandra; Olano, Agustin; Irazoqui, Gabriela; Giacomini, Cecilia; Batista-Viera, Francisco; Corzo, Nieves; Corzo-Martínez, Marta

    2016-01-01

    β-Galactosidase from Aspergillus oryzae offers a high yield for the synthesis of oligosaccharides derived from lactulose (OsLu) by transgalactosylation. Oligosaccharides with degree of polymerization (DP) ≥ 3 have shown to possess higher in vitro bifidogenic effect than di- and tetrasaccharides. Thus, in this work, an optimization of reaction conditions affecting the specific selectivity of A. oryzae β-galactosidase for synthesis of OsLu has been carried out to enhance OsLu with DP ≥ 3 production. Assays with β-galactosidase immobilized onto a glutaraldehyde–agarose support were also carried out with the aim of making the process cost-effective and industrially viable. Optimal conditions with both soluble and immobilized enzyme for the synthesis of OsLu with DP ≥ 3 were 50 °C, pH 6.5, 450 g/L of lactulose, and 8 U/mL of enzyme, reaching yields of ca. 50% (w/v) of total OsLu and ca. 20% (w/v) of OsLu with DP 3, being 6′-galactosyl-lactulose the major one, after a short reaction time. Selective formation of disaccharides, however, was favored at 60 °C, pH 4.5, 450 g/L of lactulose and 8 U/mL of enzyme. Immobilization increased the enzymatic stability to temperature changes and allowed to reuse the enzyme. We can conclude that the use, under determined optimal conditions, of the A. oryzae β-galactosidase immobilized on a support of glutaraldehyde–agarose constitutes an efficient and cost-effective alternative to the use of soluble β-galactosidases for the synthesis of prebiotic OsLu mixtures. PMID:27014684

  15. Gadolinium chloride elicits apoptosis in human osteosarcoma U-2 OS cells through extrinsic signaling, intrinsic pathway and endoplasmic reticulum stress.

    PubMed

    Tsai, Yuh-Feng; Huang, Ching-Wen; Chiang, Jo-Hua; Tsai, Fuu-Jen; Hsu, Yuan-Man; Lu, Chi-Cheng; Hsiao, Chen-Yu; Yang, Jai-Sing

    2016-12-01

    Gadolinium (Gd) compounds are important as magnetic resonance imaging (MRI) contrast agents, and are potential anticancer agents. However, no report has shown the effect of gadolinium chloride (GdCl3) on osteosarcoma in vitro. The present study investigated the apoptotic mechanism of GdCl3 on human osteosarcoma U-2 OS cells. Our results indicated that GdCl3 significantly reduced cell viability of U-2 OS cells in a concentration-dependent manner. GdCl3 led to apoptotic cell shrinkage and DNA fragmentation in U-2 OS cells as revealed by morphologic changes and TUNEL staining. Colorimetric assay analyses also showed that activities of caspase-3, caspase-8, caspase-9 and caspase-4 occurred in GdCl3-treated U-2 OS cells. Pretreatment of cells with pan-caspase inhibitor (Z-VAD-FMK) and specific inhibitors of caspase-3/-8/-9 significantly reduced cell death caused by GdCl3. The increase of cytoplasmic Ca2+ level, ROS production and the decrease of mitochondria membrane potential (ΔΨm) were observed by flow cytometric analysis in U-2 OS cells after GdCl3 exposure. Western blot analyses demonstrated that the levels of Fas, FasL, cytochrome c, Apaf-1, GADD153 and GRP78 were upregulated in GdCl3-treated U-2 OS cells. In conclusion, death receptor, mitochondria-dependent and endoplasmic reticulum (ER) stress pathways contribute to GdCl3-induced apoptosis in U-2 OS cells. GdCl3 might have potential to be used in treatment of osteosarcoma patients.

  16. Re and Os concentrations in arc basalts: The roles of volatility and source region fO 2 variations

    NASA Astrophysics Data System (ADS)

    Righter, K.; Chesley, J. T.; Caiazza, C. M.; Gibson, E. K., Jr.; Ruiz, J.

    2008-02-01

    Olivine and spinel compositions, major elements (including ferric and ferrous iron), S, Re and Os contents have been measured for a suite of primitive (most >6 wt% MgO) basalts from the Trans Mexican Volcanic Belt (TMVB), including the western Mexican volcanic belt, the Michoacan-Guanajuato Volcanic Field, Sierra Chichinautzin, Pico de Orizaba region, Palma Sola, San Martin Tuxtlas, and the eastern alkaline province (EAP). Sulfur contents at sulfide saturation were calculated to determine whether the measured S contents are representative of sulfide saturated liquids. Most of the samples have S contents much lower than expected for sulfide saturation. A few have higher contents than calculated perhaps due to the presence of sulfate in the measured total sulfur (i.e., more oxidized samples). Comparison of the TMVB samples along with previously analyzed MORB, OIB, BABB and arc samples reveals a continuum of Re and Os contents that is best explained by variation in oxygen fugacity—and thus sulfide stability—in the source region. High Re and Os magmatic suites are best explained by derivation by melting of oxidized mantle, where sulfide is no longer stable and Re and Os behave incompatibly, whereas low Re and Os magmatic suites are derived from melting of relatively reduced mantle where sulfide is stable, and Re and Os behave compatibly. Intermediate examples abound, and arc magmas span a wide range of Re and Os concentrations due to variation of fO 2 in the source during genesis of arc magmas. Low Re magmatic suites are furthermore potentially affected by volatility which can lower Re by a factor of 3-5.

  17. Zygomycetes From Herbivore Dung in the Ecological Reserve of Dois IrmÃOs, Northeast Brazil

    PubMed Central

    de Azevedo Santiago, André Luiz Cabral Monteiro; Botelho Trufem, Sandra Farto; Malosso, Elaine; dos Santos, Paulo Jorge Parreira; de Queiroz Cavalcanti, Maria Auxiliadora

    2011-01-01

    Thirty-eight taxa of Zygomycetes distributed in 15 genera were recorded from tapir (Tapirus terrestris), camel (Camelus bactrianus), horse (Equus caballus), deer (Cervus elaphus), agouti (Dasyprocta aguti), donkey (Equus asinus), llama (Llama glama) and waterbuck (Kobus ellipsiprymnus) dung collected at the Reserva Ecológica de Dois Irmãos located in Recife, State of Pernambuco, Northeast Brazil. The samples were collected on a monthly basis from June 2005 to May 2006, taken to the laboratory and incubated in moist chambers. Higher number of taxa was observed in the excrements of tapir, followed by deer and donkey. The highest number of species was detected for Mucor, followed by Pilobolus. Statistical analyses showed significant differences in richness of Zygomycetes taxa between the herbivore dung types. Differences of species composition, however, were weak. Seasonality influenced the Zygomycetes species composition but not its richness. Variations in taxa composition between ruminants and non-ruminants dung were non significant. PMID:24031609

  18. Evidence for intrinsic superconductivity at Tc1 in PrOs4Sb12

    NASA Astrophysics Data System (ADS)

    Andraka, B.; Pocsy, K.

    2012-04-01

    Superconductivity in PrOs4Sb12 shows unusual sample size dependence. Large good quality crystals exhibit two superconducting transitions at Tc1 (˜1.85 K) and Tc2 (˜1.74 K). The upper temperature transition is manifested by the change of slope in C/T. It is shown that this transition is suppressed when the crystal is polished to a thickness smaller than 50 μm. At the same time the polishing enhances the transition at Tc2. This behavior is independent on whether material studied is removed from the interior or contains the original surface of the as-cast crystal. The effect of sample polishing is similar to that of powdering, which clearly induces a large number of defects.

  19. HPC Colony II: FAST_OS II: Operating Systems and Runtime Systems at Extreme Scale

    SciTech Connect

    Moreira, Jose

    2013-11-13

    HPC Colony II has been a 36-month project focused on providing portable performance for leadership class machines—a task made difficult by the emerging variety of more complex computer architectures. The project attempts to move the burden of portable performance to adaptive system software, thereby allowing domain scientists to concentrate on their field rather than the fine details of a new leadership class machine. To accomplish our goals, we focused on adding intelligence into the system software stack. Our revised components include: new techniques to address OS jitter; new techniques to dynamically address load imbalances; new techniques to map resources according to architectural subtleties and application dynamic behavior; new techniques to dramatically improve the performance of checkpoint-restart; and new techniques to address membership service issues at scale.

  20. VLA and Swift XRT Observations of PTF12os in NGC 5806

    NASA Astrophysics Data System (ADS)

    Stockdale, C. J.; Immler, S.; Horesh, A.; Kasliwal, M.; Ryder, S. D.; Weiler, K. W.; Van Dyk, S. D.; Panagia, N.; Bauer, F. E.; Marcaide, J. M.; Pooley, D.; Sramek, R. A.; Williams, C. L.

    2012-01-01

    We report the detection of radio emission near the position of the type-IIb supernova PTF2012os (ATEL #3881) with the Karl G. Jansky Very Large Array radio telescope in the DnC configuration: A flux density of 0.44 ± 0.05 mJy was measured at 5.02 GHz (wavelength 6.0 cm) on 2012 Jan. 22.42 UT. The measured position of the radio emission of R.A. = 14h59m59.s12, Decl. = +01d53m23s.3, equinox 2000.0 is in good agreement with the measured optical position of (ending digits) R.A.

  1. Structure of the K{sup {pi}=}4{sup +} bands in {sup 186,188}Os

    SciTech Connect

    Phillips, A. A.; Garrett, P. E.; Demand, G. A.; Finlay, P.; Green, K. L.; Leach, K. G.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Lo Iudice, N.; Sushkov, A. V.; Bettermann, L.; Braun, N.; Burke, D. G.; Faestermann, T.; Kruecken, R.; Wirth, H.-F.; Hertenberger, R.

    2010-09-15

    The ({sup 3}He, d) single-proton stripping reaction has been performed on targets of {sup 185,187}Re to investigate the structures of the 4{sub 3}{sup +} states in {sup 186,188}Os. The experiment employed 30 MeV {sup 3}He beams, and the reaction products were analyzed with a Q3D spectrograph. Absolute cross sections were determined at nine angles between 5 deg. and 50 deg. for states up to approximately 3 MeV in excitation energy. Large (5/2){sup +}[402]{sub {pi}+}(3/2){sup +}[402]{sub {pi}}two-quasiparticle components are deduced for the 4{sub 3}{sup +} levels of both isotopes. Their magnitudes are in agreement with calculations performed using the quasiparticle phonon model, which predicts a coexistence of a large hexadecapole with a smaller, but sizable, {gamma}-{gamma} component in the 4{sub 3}{sup +}.

  2. Time-reversal-breaking topological phases in antiferromagnetic Sr2FeOsO6 films

    NASA Astrophysics Data System (ADS)

    Dong, Xiao-Yu; Kanungo, Sudipta; Yan, Binghai; Liu, Chao-Xing

    2016-12-01

    In this work, we studied time-reversal-breaking topological phases as a result of the interplay between antiferromagnetism and inverted band structures in antiferromagnetic double perovskite transition-metal Sr2FeOsO6 films. By combining the first-principles calculations and analytical models, we demonstrate that the quantum anomalous Hall phase and chiral topological superconducting phase can be realized in this system. We find that to achieve time-reversal-breaking topological phases in antiferromagnetic materials, it is essential to break the combined symmetry of time reversal and inversion, which generally exists in antiferromagnetic structures. As a result, we can utilize an external electric gate voltage to induce the phase transition between topological phases and trivial phases, thus providing an electrically controllable topological platform for future transport experiments.

  3. Iminimycin A, the new iminium metabolite produced by Streptomyces griseus OS-3601.

    PubMed

    Nakashima, Takuji; Miyano, Rei; Iwatsuki, Masato; Shirahata, Tatsuya; Kimura, Toru; Asami, Yukihiro; Kobayashi, Yoshinori; Shiomi, Kazuro; Petersson, George A; Takahashi, Yōko; Ōmura, Satoshi

    2016-08-01

    A new natural product, designated iminimycin A, was isolated from the cultured broth of a streptomycin-producing microbial strain, Streptomyces griseus OS-3601, via a physicochemical screening method using HP-20, silica gel and ODS column chromatographies and subsequent preparative HPLC. Iminimycin A is an indolizidine alkaloid, containing of an unusual iminium group and a cyclopropane ring with a triene side chain. The absolute configuration of iminimycin A was elucidated by NMR studies and electronic circular dichroism analysis. Iminimycin A shows anti-bacterial activity against Bacillus subtilis, Kocuria rhizophila and Xanthomonas campestris pv. orizae, and cytotoxic activity against HeLa S3 and Jurkat cells with IC50 values of 43 and 36 μM, respectively.

  4. Zygomycetes From Herbivore Dung in the Ecological Reserve of Dois IrmÃOs, Northeast Brazil.

    PubMed

    de Azevedo Santiago, André Luiz Cabral Monteiro; Botelho Trufem, Sandra Farto; Malosso, Elaine; Dos Santos, Paulo Jorge Parreira; de Queiroz Cavalcanti, Maria Auxiliadora

    2011-01-01

    Thirty-eight taxa of Zygomycetes distributed in 15 genera were recorded from tapir (Tapirus terrestris), camel (Camelus bactrianus), horse (Equus caballus), deer (Cervus elaphus), agouti (Dasyprocta aguti), donkey (Equus asinus), llama (Llama glama) and waterbuck (Kobus ellipsiprymnus) dung collected at the Reserva Ecológica de Dois Irmãos located in Recife, State of Pernambuco, Northeast Brazil. The samples were collected on a monthly basis from June 2005 to May 2006, taken to the laboratory and incubated in moist chambers. Higher number of taxa was observed in the excrements of tapir, followed by deer and donkey. The highest number of species was detected for Mucor, followed by Pilobolus. Statistical analyses showed significant differences in richness of Zygomycetes taxa between the herbivore dung types. Differences of species composition, however, were weak. Seasonality influenced the Zygomycetes species composition but not its richness. Variations in taxa composition between ruminants and non-ruminants dung were non significant.

  5. Magnetically driven metal-insulator transition in NaOsO3.

    PubMed

    Calder, S; Garlea, V O; McMorrow, D F; Lumsden, M D; Stone, M B; Lang, J C; Kim, J-W; Schlueter, J A; Shi, Y G; Yamaura, K; Sun, Y S; Tsujimoto, Y; Christianson, A D

    2012-06-22

    The metal-insulator transition (MIT) is one of the most dramatic manifestations of electron correlations in materials. Various mechanisms producing MITs have been extensively considered, including the Mott (electron localization via Coulomb repulsion), Anderson (localization via disorder), and Peierls (localization via distortion of a periodic one-dimensional lattice) mechanisms. One additional route to a MIT proposed by Slater, in which long-range magnetic order in a three dimensional system drives the MIT, has received relatively little attention. Using neutron and x-ray scattering we show that the MIT in NaOsO(3) is coincident with the onset of long-range commensurate three dimensional magnetic order. While candidate materials have been suggested, our experimental methodology allows the first definitive demonstration of the long predicted Slater MIT.

  6. Magnetically Driven Metal-Insulator Transition in NaOsO3

    SciTech Connect

    Calder, Stuart A; Christianson, Andrew D; Lumsden, Mark D; Lang, Jonathan; Stone, Matthew B; McMorrow, D. F.; Garlea, Vasile O; Kim, Jong-Woo; Schlueter, J. A.; Shi, Y. G.; Yamaura, K.; Sun, Y. S.; Tsujimoto, Y.

    2012-01-01

    The metal-insulator transition (MIT) is one of the most dramatic manifestations of electron correlations in materials. Various mechanisms producing MITs have been extensively considered, including the Mott (electron localization via Coulomb repulsion), Anderson (localization via disorder), and Peierls (local- ization via distortion of a periodic one-dimensional lattice) mechanisms. One additional route to a MIT proposed by Slater, in which long-range magnetic order in a three dimensional system drives the MIT, has received relatively little attention. Using neutron and x-ray scattering we show that the MIT in NaOsO3 is coincident with the onset of long-range commensurate three dimensional magnetic order. While candidate materials have been suggested, our experimental methodology allows the first definitive demonstration of the long predicted Slater MIT.

  7. Production in vitro of thyroglobulin autoantibody by obese strain (OS) chickens.

    PubMed Central

    Tempelis, C H; Schauenstein, K; Wick, G

    1987-01-01

    Thyroglobulin autoantibody (Tg-AAb) can be spontaneously produced in vitro with thyroid infiltrating lymphocytes (TIL) collected from Obese strain chickens 3.5 and 4 weeks old. Attempts to enhance Tg-AAb synthesis with two known polyclonal stimulators of immunoglobulin synthesis in chickens, Staphylococcus aureus Cowan strain 1 and dextran sulphate, failed to increase Tg-AAb production in vitro. Spleen cells and peripheral blood lymphocytes obtained from the same chickens as the TIL and older chickens known to produce moderate to high levels of Tg-AAb in vivo did not produce autoantibody either spontaneously or in the presence of polyclonal Ig stimulators with one exception. With this single, exceptional chicken we obtained a small amount of Tg-AAb produced in vitro with spleen cells. This suggests that in the OS chicken TIL, and to a much lesser extent, the spleen, contribute to the total Tg-AAb produced in this model of autoimmune thyroiditis. PMID:2440629

  8. [The Hospital Real de Todos-os-Santos and its healing agents].

    PubMed

    Silva, Priscila Aquino

    2015-12-01

    The article explores the actions of king Dom João II (1481-1495), who spearheaded a major assistance reform in Portugal during the late fifteenth century, when charitable institutions were grappling with a serious crisis. The king and his queen, Dona Leonor, ordered two large, modern hospitals to be built, centralizing assistance work and cementing a new assistance model. Relying on chronicles and royal decrees from the period, the article focuses on the main hospital that was built then: Hospital Real de Todos-os-Santos, located in Lisbon. The king and queen also intervened heavily in the practice of health agents by regulating, overseeing, and inspecting the work of doctors and apothecaries.

  9. Mineralization of bone-related SaOS-2 cells under physiological hypoxic conditions.

    PubMed

    Müller, Werner E G; Schröder, Heinz C; Tolba, Emad; Diehl-Seifert, Bärbel; Wang, Xiaohong

    2016-01-01

    Inorganic polyphosphate (polyP) is a physiological energy-rich polymer with multiple phosphoric anhydride bonds. In cells such as bone-forming osteoblasts, glycolysis is the main pathway generating metabolic energy in the form of ATP. In the present study, we show that, under hypoxic culture conditions, the growth/viability of osteoblast-like SaOS-2 cells is not impaired. The addition of polyP to those cells, administered as amorphous calcium polyP nanoparticles (aCa-polyP-NP; approximate size 100 nm), significantly increased the proliferation of the cells. In the presence of polyP, the cells produce significant levels of lactate, the end product of anaerobic glycolysis. Under those conditions, an eight-fold increase in the steady-state level of the membrane-associated carbonic anhydrase IX is found, as well as a six-fold induction of the hypoxia-inducible factor 1. Consequently, biomineral formation onto the SaOS-2 cells decreases under low oxygen tension. If the polyP nanoparticles are added to the cells, the degree of mineralization is enhanced. These changes had been measured also in human mesenchymal stem cells. The assumption that the bicarbonate, generated by the carbonic anhydrase in the presence of polyP under low oxygen, is deposited as a constituent of the bioseeds formed during initial hydroxyapatite formation is corroborated by the identification of carbon besides of calcium, oxygen and phosphorus in the initial biomineral deposit onto the cells using the sensitive technology of high-resolution energy dispersive spectrometry mapping. Based on these data, we conclude that polyP is required for the supply of metabolic energy during bone mineral formation under physiological, hypoxic conditions, acting as a 'metabolic fuel' for the cells to grow.

  10. Spatiotemporal appraisal of TBT contamination and imposex along a tropical bay (Todos os Santos Bay, Brazil).

    PubMed

    Artifon, Vanda; Castro, Ítalo Braga; Fillmann, Gilberto

    2016-08-01

    A spatiotemporal evaluation of butyltin contamination was performed between 2010 and 2012 along Todos os Santos Bay (Northeast Brazil) using surface sediments, bivalve tissues (Anomalocardia brasiliana and Mytella guyanensis), and imposex occurrence (Stramonita rustica). The spatial study detected high tributyltin (TBT) levels (maximum values of 262 ng Sn g (-1) - 21,833 ng Sn g(-1) of total organic carbon - for surface sediments and 421 ng Sn g(-1) for bivalve tissues) in the innermost part of the bay. The TBT levels detected in M. guyanensis tissues might cause human health risk since local population consumes these organisms. These high concentrations observed in the bivalves might result in ingestions higher than the safe limits established by European Food Safety Authority (250 ng TBT kg(-1) day(-1)). Considering the temporal evaluation, no difference (p > 0.05) was observed between TBT concentrations in sediments obtained during the two sampling campaigns (2010/2011 and 2012). However, the increasing predominance of TBT metabolites (butyltin degradation index (BDI) >1) in more recent sediments indicates further degradation of old TBT inputs. In spite of that, recent inputs are still evident at this region. Nevertheless, a reduction of imposex parameters in S. rustica over the last decade suggests an overall decline in the TBT contamination, at least in the outermost and possible less impacted region of the bay. The TBT contamination is probably reducing due to the national and international legislative restrictions on the use of TBT as antifouling biocide. The contamination levels, however, are still relevant especially in the inner part of Todos os Santos Bay since they are above those that are likely to cause toxicity to the biota.

  11. An Environmental Management Model of Thermal Waters in Entre Ríos Province, Argentina

    NASA Astrophysics Data System (ADS)

    Pablo, Mársico Daniel; Luís, Díaz Eduardo; Ivana, Zecca; Oscar, Dallacosta; Antonio, Paz-González

    2015-04-01

    Deep exploratory drillings, i.e. those with more than 500 meters depth, have been performed in the Entre Ríos province, Argentina, in order to ascertain the presence of thermal water. Drilling began in 1994, and until now there have been 18 polls with very variable results in terms of mineralization, resource flow, and temperature. The aim of this study was to present a management model, which should allow operators of thermal complexes to further develop procedures for safeguarding the biodiversity of the ecosystems involved, both during exploration and exploitation activities. The environmental management Plan proposed is constituted by a set of technical procedures that are formulated and should be performed during the stages of exploration and exploitation of the resource, and consists of: environmental monitoring, environmental audit, public information and contingency programs. This Plan describes the measures and proposals aimed at protecting environmental quality in the area of influence of a thermal complex project, ensuring that its execution remains environmentally responsibly, and allowing implementation of specific actions to prevent or correct environmental impacts, as predicted in the evaluation of the Environmental Program. The audit of environmental impact includes and takes into account natural factors, such as water, soil, atmosphere, flora and fauna, and also cultural factors. The technical audit Plan was prepared in order to get a systematic structure and organization of the verification process, and also with regard to document the degree of implementation of the proposed mitigation measures. Finally, an environmental contingency program was implemented, and its objective was to consider the safeguarding of life and its natural environment. Thus, a guide has been developed with the main actions to be taken on a contingency, since forecast increases the efficiency of the response. The methodology developed here was adopted as the procedure

  12. Overexpressing OsPIN2 enhances aluminium internalization by elevating vesicular trafficking in rice root apex.

    PubMed

    Wu, Daoming; Shen, Hong; Yokawa, Ken; Baluška, František

    2015-11-01

    Aluminium (Al) sequestration is required for internal detoxification of Al in plant cells. In this study, it was found that the rice OsPIN2 overexpression line (OX1) had significantly reduced Al content in its cell wall and increased Al concentration in cell sap only in rice root tips relative to the wild-type (WT). In comparison with WT, OX1 reduced morin staining of cytosolic Al, enhanced FM 4-64 staining of membrane vesicular trafficking in root tip sections (0-1mm), and showed morin-FM 4-64 fluorescence overlap. Recovery treatment showed that cell-wall-bound Al was internalized into vacuoles via endocytic vesicular trafficking after removal of external Al. In this process, OX1 showed a higher rate of Al internalization than WT. Brefeldin A (BFA) interfered with vesicular trafficking and resulted in inhibition of Al internalization. This inhibitory effect could be alleviated when BFA was washed out, and the process of alleviation was slower in the cells of WT than in those of OX1. Microscopic observations revealed that, upon Al exposure, numerous multilamellar endosomes were detected between the cell wall and plasma membrane in the cells of OX1. Moreover, more vesicles enriched with Al complexes accumulated in the cells of OX1 than in those of WT, and these vesicles transformed into larger structures in the cells of OX1. Taken together, the data indicate that endocytic vesicular trafficking might contribute to Al internalization, and that overexpressing OsPIN2 enhances rice Al tolerance via elevated endocytic vesicular trafficking and Al internalization.

  13. Aberrant Expression of MICO1 and MICO1OS in Deceased Somatic Cell Nuclear Transfer Calves.

    PubMed

    Wang, Guan-Nan; Yang, Wen-Zhi; Xu, Da; Li, Dong-Jie; Zhang, Cui; Chen, Wei-Na; Li, Shi-Jie

    2017-04-06

    Incomplete reprogramming of a donor nucleus following somatic cell nuclear transfer (SCNT) results in aberrant expression of developmentally important genes, and is the primary source of the phenotypic abnormalities observed in cloned animals. Expression of non-coding RNAs in the murine Dlk1-Dio3 imprinted domain was previously shown to correlate with the pluripotency of mouse induced pluripotent stem cells. In this study, we examined the transcription of the bovine orthologs from this locus, MICO1 (Maternal intergenic circadian oscillating 1) and MICO1OS (MICO1 opposite strand), in tissues from artificially inseminated and SCNT calves that died during the perinatal period. A single-nucleotide polymorphism (SNP), a T-to-C transition, was used to analyze the allelic transcription of MICO1. Our results indicate monoallelic expression of the MICO1 C allele among the six analyzed tissues (heart, liver, spleen, lung, kidney, and brain) of artificially inseminated calves, indicating that this gene locus may be imprinted in bovine. Conversely, we observed variable allelic transcription of MICO1 in SCNT calves. We asked if DNA methylation regulated the monoallelic expression of MICO1 and MICO1OS by evaluating the methylation levels of six regions within or around this locus in tissues with normal or aberrant MICO1 transcription; all of the samples from either artificially inseminated or SCNT calves exhibited hypermethylation, implying that DNA methylation may not be involved in regulating its monoallelic expression. Furthermore, three imprinted genes (GTL2, MEG9, and DIO3) nearby MICO1 showed monoallelic expression in SCNT calves with aberrant MICO1 transcription, indicating that not all of the genes in the bovine DLK1-DIO3 domain are mis-regulated. This article is protected by copyright. All rights reserved.

  14. Effect of siRNA PERK on fluoride-induced osteoblastic differentiation in OS732 cells.

    PubMed

    Lü, Peng; Li, Xining; Ruan, Lihong; Xu, Hui; Liu, Qinyi

    2014-06-01

    The purpose of this work is to study the action of fluoride on osteoblastic function through knocking down double-stranded RNA-activated protein kinase (PKR)-like ER kinase (PERK) mRNA in OS732 cells (human osteoblast-like cell line). The previous researches had demonstrated that fluoride induced endoplasmic reticulum (ER) stresses in other cells or tissues. PERK as one branch of UPR to combat ER stress played a role in mediating the proliferation and differentiation of osteoblast. The mechanism of skeletal fluorosis by which fluoride regulated osteoblast was not fully defined. We used the real-time PCR and small interfering RNA techniques to determine the expression PERK signaling and osteoblastic and osteoclastic differentiation-related factors and investigated the role of PERK signaling in fluoride-stimulated osteoblastic function. Cells transfected with 50 nM small interfering RNA (siRNA)-PERK showed effectively decreased protein and gene expression of PERK and reduced protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2). Meantime, cells transfected with siRNA significantly decreased the protein level of alkaline phosphatase (ALP) and nuclear factor kappa B ligand (RANKL) in cells under fluoride exposure. It suggested that knockdown of PERK expression hardly stimulated osteoblastic and osteoclastic early differentiation induced by fluoride. Conversely, there were littler effect of siRNA PERK on expression of Runt-related transcription factor 2 (RUNX2) and osteoprotegerin (OPG) in cells, but fluoride exposure markedly stimulated their expression. This study proved that the mechanism underlying fluoride induced osteoblastic and osteoclastic differentiation possible was due to activation of ALP and RANKL mediated by PERK in OS732 cells.

  15. Ectopic expression of EbFIE from apomictic Eulaliopsis binata in rice results in pleiotropic phenotypes likely due to interaction with OsCLF.

    PubMed

    Ma, Kai; Zhang, Dongliang; Liu, Yaqin; Ouyang, Yidan; Li, Jiajia; Hu, Chungen; Yao, Jialing

    2015-05-01

    FERTILIZATION INDEPENDENT ENDOSPERM (FIE) is a core component of PcG complexes and functions in plant phase transition and seed generation. However, understanding in its function of apomictic monocot plants remains blank. Here an FIE homology EbFIE, has been isolated from apomictic Graminae species Eulaliopsis binata. EbFIE shares higher homology to OsFIE2 than OsFIE1, and has been classified into the monocot FIE2 clade. In addition, the broad expression pattern of EbFIE is also similar to OsFIE2. While, ectopic expression of EbFIE in rice resulted in pleiotropic phenotypes similar to that of OsFIE1 over-expressing plants. Meanwhile, EbFIE could bind OsCLF in vitro as OsFIE1 but different with OsFIE2. Molecular models comparison indicated that both EbFIE and OsFIE1 had a smaller E(z) protein binding groove than OsFIE2. Further site-directed mutagenesis analysis revealed that single amino acid substitution of I194F in OsFIE2 could improve its OsCLF binding capacity. Taken together, our results suggested that EbFIE was a conserved FIE homolog belonging to monocot FIE2 clade, but due to the similarity in protein conformation with FIE1, EbFIE might play a broad role in vegetative and reproductive development regulation by interaction with CLF homolog.

  16. Fragile singlet ground-state magnetism in the pyrochlore osmates R2Os2O7 ( R=Y and Ho)

    DOE PAGES

    Zhao, Z. Y.; Calder, S.; Aczel, A. A.; ...

    2016-04-25

    The singlet ground state magnetism in pyrochlore osmates Y2Os2O7 and Ho2Os2O7 is studied by DC and AC susceptibility, specific heat, and neutron powder di raction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os4+ (5d4), Y2Os2O7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho2Os2O7 has the same structural distortion as occurs in Y2Os2O7. However, the Os sublattice in Ho2Os2O7 shows long- range magneticmore » ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y2Os2O7 and Ho2Os2O7 signals the singlet ground state magnetism in R2 Os2 O7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

  17. The NF-YA transcription factor OsNF-YA7 confers drought stress tolerance of rice in an abscisic acid independent manner.

    PubMed

    Lee, Dong-Keun; Kim, Hyung Il; Jang, Geupil; Chung, Pil Joong; Jeong, Jin Seo; Kim, Youn Shic; Bang, Seung Woon; Jung, Harin; Choi, Yang Do; Kim, Ju-Kon

    2015-12-01

    The mechanisms of plant response and adaptation to drought stress require the regulation of transcriptional networks via the induction of drought-responsive transcription factors. Nuclear Factor Y (NF-Y) transcription factors have aroused interest in roles of plant drought stress responses. However, the molecular mechanism of the NF-Y-induced drought tolerance is not well understood. Here, we functionally analyzed two rice NF-YA genes, OsNF-YA7 and OsNF-YA4. Expression of OsNF-YA7 was induced by drought stress and its overexpression in transgenic rice plants improved their drought tolerance. In contrast, OsNF-YA4 expression was not increased by drought stress and its overexpression in transgenic rice plants did not affect their sensitivity to drought stress. OsNF-YA4 expression was highly induced by the stress-related hormone abscisic acid (ABA), while OsNF-YA7 was not, indicating that OsNF-YA7 mediates drought tolerance in an ABA-independent manner. Analysis of the OsNF-YA7 promoter revealed three ABA-independent DRE/CTR elements and RNA-seq analysis identified 48 genes downstream of OsNFYA7 action putatively involved in the OsNF-YA7-mediated drought tolerance pathway. Taken together, our results suggest an important role for OsNF-YA7 in rice drought stress tolerance.

  18. Os-Hf isotopes of the ultrapotassic rocks in southern Tibet: Significant crustal input into the mantle source region

    NASA Astrophysics Data System (ADS)

    Zhao, Z.; Widom, E.; Meng, Q.; Niu, Y.; Zhu, D.; Mo, X.; Barry, T.

    2010-12-01

    The post-collisional mafic ultrapotassic (ultra-K) magmatism in the western Lhasa terrane, southern Tibet, has been well-studied in the past decade. The model of low-degree partial melting of an enriched subcontinental lithospheric mantle has been proposed to be responsible for the origin of the ultra-K rocks on the basis of trace element and Sr-Nd-Pb-O isotope data (Miller et al., 1999, J. Petrology; Ding et al., 2003, J. Petrology; Gao et al., 2009, J. Petrology; Zhao et al., 2009, Lithos). Here, we report both Os and Hf isotopic data on the same ultra-K samples discussed in Zhao et al. (2009). The rocks have suprachondritic 187Os/188Os (0.1315-0.4828) and sub-chondritic to MORB-like Re/Os ratios (0.019-15.75). In the 187Os/188Os vs. Re/Os plot, the data show a notable trend towards the Himalayan crustal components. The 176Hf/177Hf ratios of 0.282204 to 0.282554 correspond to ɛHf values of -20.1 to -7.9. In the ɛHf vs. ɛNd plot, these mafic ultra-K rocks show strong crustal signatures, similar to, but more enriched than, the lamproites from Spain and Italia (Prelević et al., 2010, Lithos). They also show a linear trend that coincides with the Hf-Nd isotopic array defined by igneous rocks, suggesting significant contributions of some mature continental crustal material in their petrogenesis. The radiogenic Os could be interpreted as resulting from crustal assimilation, but more likely reflects increasing contributions from metasomatic components (Schaefer et al., 2000, Geology). Taking together all the trace element data, Os-Hf-Nd data and petrological data, we suggest that the petrogenesis of the mantle xenolith-bearing ultra-K rocks in southern Tibet involves melting of enriched upper mantle whose enrichments may be genetically associated with metasomatism by a melt component derived from subducted Himalayan continental crustal materials.

  19. Comment on "Behavior of Re and Os during contact between an aqueous solution and oil: Consequences for the application of the Re-Os geochronometer to petroleum" [Geochim. Cosmochim. Acta 158 (2015) 1-21

    NASA Astrophysics Data System (ADS)

    Wu, Jia; Li, Zhen; Wang, Xuan-ce

    2016-08-01

    In a recent study, Mahdaoui et al. (2015) simulated the contact of oil with Re/Os-bearing aqueous fluids in petroleum reservoirs and concluded that both metals could be rapidly and substantially enriched in the oil fraction. These findings could have significant geological ramifications for the use of rhenium-osmium (Re-Os) geochronology in the age-dating of oil deposits. However, the lack of data reproducibility between parallel experiments and misused parameter of "recovery rate" has cast doubt on the main conclusions of the paper. Re-analyses of the raw data provided sufficient evidence to suggest that in petroleum basins with very low abundances of Re and Os, the extraction of these metals to oil is unlikely to be a geologically instantaneous process as the authors implied in their study. In addition, the possibility of reactor leakage in the contacting experiments cannot be completely ruled out.

  20. A comparative proteomics study on matrix vesicles of osteoblast-like Saos-2 and U2-OS cells.

    PubMed

    Jiang, Liang; Cui, Yazhou; Luan, Jing; Zhou, Xiaoyan; Zhou, Xiaoying; Han, Jinxiang

    2013-05-01

    Matrix vesicles (MVs) play an important role in the initial stage of the process of bone mineralization, and are involved in multiple rare skeletal diseases with pathological mineralization or calcification. The aim of the study was to compare the proteomic profiling of osteoblast-like cells with and without mineralization ability (Saos-2 and U2-OS), and to identify novel mineralization-associated MV proteins. MVs were extracted using ExoQuick solution from mineralization-induced Saos-2 and U2-OS cells, and then were validated by transmission electron microscopy. A label-free quantitative proteomic method was used to compare the protein profiling of MVs from Saos-2 and U2-OS cells. Western-blots were used to confirm the expression of MVs proteins identified in proteomic studies. In our proteomic studies, we identified that 89 mineralization-related proteins were significantly up-regulated in Saos-2 MVs compared with U2-OS MVs. We further validated that two MVs proteins, protein kinase C α and ras-related protein Ral-A, were up-regulated in MVs of Saos-2 cells compared to those of U2-OS cells under mineralization-induction. Our findings suggest that protein kinase C α and ras-related protein Ral-A might be involved in bone mineralization as MVs components.

  1. Regulatory Role of OsMADS34 in the Determination of Glumes Fate, Grain Yield, and Quality in Rice

    PubMed Central

    Ren, Deyong; Rao, Yuchun; Leng, Yujia; Li, Zizhuang; Xu, Qiankun; Wu, Liwen; Qiu, Zhennan; Xue, Dawei; Zeng, Dali; Hu, Jiang; Zhang, Guangheng; Zhu, Li; Gao, Zhenyu; Chen, Guang; Dong, Guojun; Guo, Longbiao; Qian, Qian

    2016-01-01

    Grasses produce seeds on spikelets, a unique type of inflorescence. Despite the importance of grass crops for food, the genetic mechanisms that control spikelet development remain poorly understood. In this study, we used m34-z, a new mutant allele of the rice (Oryza sativa) E-class gene OsMADS34, to examine OsMADS34 function in determining the identities of glumes (rudimentary glume and sterile lemma) and grain size. In the m34-z mutant, both the rudimentary glume and sterile lemma were homeotically converted to the lemma-like organ and acquired the lemma identity, suggesting that OsMADS34 plays important roles in the development of glumes. In the m34-z mutant, most of the grains from the secondary panicle branches (spb) were decreased in size, compared with grains from wild-type, but no differences were observed in the grains from the primary panicle branches. The amylose content and gel consistency, and a seed-setting rate from the spb were reduced in the m34-z mutant. Interesting, transcriptional activity analysis revealed that OsMADS34 protein was a transcription repressor and it may influence grain yield by suppressing the expressions of BG1, GW8, GW2, and GL7 in the m34-z mutant. These findings revealed that OsMADS34 largely affects grain yield by affecting the size of grains from the secondary branches. PMID:28018389

  2. Atomically Resolved Site-Isolated Catalyst on MgO: Mononuclear Osmium Dicarbonyls formed from Os3(CO)12

    SciTech Connect

    Aydin, Ceren; kulkarni, Apoorva; Chi, Miaofang; Browning, Nigel D.; Gates, Bruce C.

    2012-01-01

    Supported triosmium clusters, formed from Os{sub 3}(CO){sub 12} on MgO, were treated in helium at 548 K for 2 h, causing fragmentation of the cluster frame and the formation of mononuclear osmium dicarbonyls. The cluster breakup and the resultant fragmented species were characterized by infrared and X-ray absorption spectroscopies, and the fragmented species were imaged by scanning transmission electron microscopy. The spectra identify the surface osmium complexes as Os(CO){sub 2}{l_brace}O{sub support}{r_brace}{sub n} (n = 3 or 4) (where the braces denote support surface atoms). The images show site-isolated Os atoms in mononuclear osmium species on MgO. The intensity analysis on the images of the MgO(110) face showed that the Os atoms were located atop Mg columns. This information led to a model of the Os(CO){sub 2} on MgO(110), with the distances approximated as those determined by EXAFS spectroscopy, which are an average over the whole MgO surface; the results imply that these complexes were located at Mg vacancies.

  3. OsJAR1 is required for JA-regulated floret opening and anther dehiscence in rice.

    PubMed

    Xiao, Yuguo; Chen, Yi; Charnikhova, Tatsiana; Mulder, Patrick P J; Heijmans, Jeroen; Hoogenboom, Angela; Agalou, Adamantia; Michel, Corinne; Morel, Jean-Benoit; Dreni, Ludovico; Kater, Martin M; Bouwmeester, Harro; Wang, Mei; Zhu, Zhen; Ouwerkerk, Pieter B F

    2014-09-01

    Jasmonates are important phytohormones regulating reproductive development. We used two recessive rice Tos17 alleles of OsJAR1, osjar1-2 and osjar1-3, to study the biological function of jasmonates in rice anthesis. The florets of both osjar1 alleles stayed open during anthesis because the lodicules, which control flower opening in rice, were not withering on time. Furthermore, dehiscence of the anthers filled with viable pollen, was impaired, resulting in lower fertility. In situ hybridization and promoter GUS transgenic analysis confirmed OsJAR1 expression in these floral tissues. Flower opening induced by exogenous applied methyl jasmonate was impaired in osjar1 plants and was restored in a complementation experiment with transgenics expressing a wild type copy of OsJAR1 controlled by a rice actin promoter. Biochemical analysis showed that OsJAR1 encoded an enzyme conjugating jasmonic acid (JA) to at least Ile, Leu, Met, Phe, Trp and Val and both osjar1 alleles had substantial reduction in content of JA-Ile, JA-Leu and JA-Val in florets. We conclude that OsJAR1 is a JA-amino acid synthetase that is required for optimal flower opening and closing and anther dehiscence in rice.

  4. OsPT2, a phosphate transporter, is involved in the active uptake of selenite in rice.

    PubMed

    Zhang, Lianhe; Hu, Bin; Li, Wei; Che, Ronghui; Deng, Kun; Li, Hua; Yu, Feiyan; Ling, Hongqing; Li, Youjun; Chu, Chengcai

    2014-03-01

    • Selenite is a predominant form of selenium (Se) available to plants, especially in anaerobic soils, but the molecular mechanism of selenite uptake by plants is not well understood. • ltn1, a rice mutant previously shown to have increased phosphate (Pi) uptake, was found to exhibit higher selenite uptake than the wild-type in both concentration- and time-dependent selenite uptake assays. Respiratory inhibitors significantly inhibited selenite uptake in the wildtype and the ltn1 mutant, indicating that selenite uptake was coupled with H(+) and energy-dependent. Selenite uptake was greatly enhanced under Pi-starvation conditions, suggesting that Pi transporters are involved in selenite uptake. • OsPT2, the most abundantly expressed Pi transporter in the roots, is also significantly up-regulated in ltn1 and dramatically induced by Pi starvation. OsPT2-overexpressing and knockdown plants displayed significantly increased and decreased rates of selenite uptake, respectively, suggesting that OsPT2 plays a crucial role in selenite uptake. Se content in rice grains also increased significantly in OsPT2-overexpressing plants. • These data strongly demonstrate that selenite and Pi share similar uptake mechanisms and that OsPT2 is involved in selenite uptake, which provides a potential strategy for breeding Se-enriched rice varieties.

  5. Ostreid herpesvirus 1 (OsHV-1) detection among three successive generations of Pacific oysters (Crassostrea gigas).

    PubMed

    Barbosa-Solomieu, V; Dégremont, L; Vázquez-Juárez, R; Ascencio-Valle, F; Boudry, P; Renault, T

    2005-01-01

    Ostreid Herpesvirus 1 (OsHV-1) was likely detected in Pacific oysters, Crassostrea gigas, at different stages of development. Viral infections were associated with high mortality rates in the spat and larvae. Furthermore, the persistance of OsHV-1 in asymptomatic adults was demonstrated by detection of viral DNA and proteins. In the present study, three successive generations of C. gigas (G0 and G1 parental oysters, G1 and G2 larvae) were screened for OsHV-1 by PCR. Viral DNA was detected in 2-day-old larvae, indicating that infection may take place at very early stages. Although results strengthen the hypothesis of a vertical transmission, it was not possible to predict the issue of a particular type of cross. Indeed, the detection of viral DNA in parental oysters did not systematically correspond to a productive infection or result in a successful transmission to the progeny. However, the infective status of the parents appeared to have an influence on both the infection and the survival rates of the progeny. Crosses involving an OsHV-1 infected male and a non-infected female resulted in hatching and larval survival rates statistically lower than those observed in the other types of cross. These results suggest that OsHV-1-infected females may transmit to their offspring some kind of protection or resistance against viral infection.

  6. Physiological change under OsHV-1 contamination in Pacific oyster Crassostrea gigas through massive mortality events on fields

    PubMed Central

    2013-01-01

    Background Massive mortalities have been observed in France since 2008 on spat and juvenile Pacific oysters, Crassostrea gigas. A herpes virus called OsHV-1, easily detectable by PCR, has been implicated in the mortalities as demonstrated by the results of numerous field studies linking mortality with OsHV-1 prevalence. Moreover, experimental infections using viral particles have documented the pathogenicity of OsHV-1 but the physiological responses of host to pathogen are not well known. Results The aim of this study was to understand mechanisms brought into play against the virus during infection in the field. A microarray assay has been developed for a major part of the oyster genome and used for studying the host transcriptome across mortality on field. Spat with and without detectable OsHV-1 infection presenting or not mortality respectively were compared by microarray during mortality episodes. In this study, a number of genes are regulated in the response to pathogen infection on field and seems to argue to an implication of the virus in the observed mortality. The result allowed establishment of a hypothetic scheme of the host cell’s infection by, and response to, the pathogen. Conclusions This response shows a “sensu stricto” innate immunity through genic regulation of the virus OsHV-1 life cycle, but also others biological processes resulting to complex interactions between host and pathogens in general. PMID:23987141

  7. High-temperature ferrimagnetism driven by lattice distortion in double perovskite Ca2FeOsO6.

    PubMed

    Feng, Hai L; Arai, Masao; Matsushita, Yoshitaka; Tsujimoto, Yoshihiro; Guo, Yanfeng; Sathish, Clastin I; Wang, Xia; Yuan, Ya-Hua; Tanaka, Masahiko; Yamaura, Kazunari

    2014-03-05

    5d and 3d hybrid solid-state oxide Ca2FeOsO6 crystallizes into an ordered double-perovskite structure with a space group of P2₁/n with high-pressures and temperatures. Ca2FeOsO6 presents a long-range ferrimagnetic transition at a temperature of ~320 K (T(c)) and is not a band insulator, but is electrically insulating like the recently discovered Sr2CrOsO6 (T(c) ~725 K). The electronic stat of Ca2FeOsO6 is adjacent to a half-metallic state as well as that of Sr2CrOsO6. In addition, the high-T(c) ferrimagnetism was driven by lattice distortion, which was observed for the first time among double-perovskite oxides and represents complex interplays between spins and orbitals. Unlike conventional ferrite and garnet, the interplays likely play a pivotal role of the ferrimagnetism. A new class of 5d-3d hybrid ferrimagnetic insulators with high-T(c) is established to develop practically and scientifically useful spintronic materials.

  8. The rice thylakoid membrane-bound ascorbate peroxidase OsAPX8 functions in tolerance to bacterial blight

    PubMed Central

    Jiang, Guanghuai; Yin, Dedong; Zhao, Jiying; Chen, Honglin; Guo, Lequn; Zhu, Lihuang; Zhai, Wenxue

    2016-01-01

    Thylakoid membrane-bound ascorbate peroxidase (tAPX) is a major H2O2-scavenging enzyme. To clarify its functions in tolerance to rice bacterial blight, we produced rice lines overexpressing and suppressing tAPX (OsAPX8). The overexpressing lines exhibited increased tolerance to bacterial pathogen. The RNA interference (RNAi) lines were considerably more sensitive than the control plant. Further analysis of the H2O2 content in these transgenic plants indicated that the H2O2 accumulation of OsAPX8-overexpressing plants was considerably less than that of wild-type and RNAi plants upon challenge with bacterial pathogen. Interestingly, H2O2 was the most important factor for the serious leaf dehydration and withering of rice without major resistance genes and was not the cause of hypersensitivity. It addition, wall tightening or loosening can occur according to the level of H2O2. In addition, OsAPX8 interacted with the susceptibility protein Os8N3/Xa13, and their binding repressed the reaction of OsAPX8 in tolerance to bacterial blight. PMID:27185545

  9. The rice thylakoid membrane-bound ascorbate peroxidase OsAPX8 functions in tolerance to bacterial blight.

    PubMed

    Jiang, Guanghuai; Yin, Dedong; Zhao, Jiying; Chen, Honglin; Guo, Lequn; Zhu, Lihuang; Zhai, Wenxue

    2016-05-17

    Thylakoid membrane-bound ascorbate peroxidase (tAPX) is a major H2O2-scavenging enzyme. To clarify its functions in tolerance to rice bacterial blight, we produced rice lines overexpressing and suppressing tAPX (OsAPX8). The overexpressing lines exhibited increased tolerance to bacterial pathogen. The RNA interference (RNAi) lines were considerably more sensitive than the control plant. Further analysis of the H2O2 content in these transgenic plants indicated that the H2O2 accumulation of OsAPX8-overexpressing plants was considerably less than that of wild-type and RNAi plants upon challenge with bacterial pathogen. Interestingly, H2O2 was the most important factor for the serious leaf dehydration and withering of rice without major resistance genes and was not the cause of hypersensitivity. It addition, wall tightening or loosening can occur according to the level of H2O2. In addition, OsAPX8 interacted with the susceptibility protein Os8N3/Xa13, and their binding repressed the reaction of OsAPX8 in tolerance to bacterial blight.

  10. Photoluminescence properties and energy levels of RE (RE = Pr, Sm, Er, Tm) in layered-CaZnOS oxysulfide

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi-Jun; Feng, Ang; Chen, Xiang-Yang; Zhao, Jing-Tai

    2013-12-01

    RE3+ (RE = Pr, Sm, Er, Tm)-activated CaZnOS samples were prepared by a solid-state reaction method at high temperature, and their photoluminescence properties were investigated. Doping with RE3+ (RE = Pr, Sm, Er, Tm) into layered-CaZnOS resulted in typical RE3+ (RE = Pr, Sm, Er, Tm) f-f line absorptions and emissions, as well as the charge transfer band of Sm3+ at about 3.3 eV. The energy level scheme containing the position of the 4f and 5d levels of all divalent and trivalent lanthanide ions with respect to the valence and conduction bands of CaZnOS has been constructed based on the new data presented in this work, together with the data from literature on Ce3+ and Eu2+ doping in CaZnOS. The detailed energy level scheme provides a platform for interpreting the optical spectra and could be used to comment on the valence stability of the lanthanide ions in CaZnOS.

  11. Atomically Resolved Site-Isolated Catalyst on MgO: Mononuclear Osmium Dicarbonyls formed from Os3(CO)12.

    PubMed

    Aydin, Ceren; Kulkarni, Apoorva; Chi, Miaofang; Browning, Nigel D; Gates, Bruce C

    2012-07-19

    Supported triosmium clusters, formed from Os3(CO)12 on MgO, were treated in helium at 548 K for 2 h, causing fragmentation of the cluster frame and the formation of mononuclear osmium dicarbonyls. The cluster breakup and the resultant fragmented species were characterized by infrared and X-ray absorption spectroscopies, and the fragmented species were imaged by scanning transmission electron microscopy. The spectra identify the surface osmium complexes as Os(CO)2{Osupport}n (n = 3 or 4) (where the braces denote support surface atoms). The images show site-isolated Os atoms in mononuclear osmium species on MgO. The intensity analysis on the images of the MgO(110) face showed that the Os atoms were located atop Mg columns. This information led to a model of the Os(CO)2 on MgO(110), with the distances approximated as those determined by EXAFS spectroscopy, which are an average over the whole MgO surface; the results imply that these complexes were located at Mg vacancies.

  12. OsFIE2 plays an essential role in the regulation of rice vegetative and reproductive development.

    PubMed

    Li, Shisheng; Zhou, Bing; Peng, Xiongbo; Kuang, Quan; Huang, Xiaolong; Yao, Jialing; Du, Bo; Sun, Meng-Xiang

    2014-01-01

    Polycomb group (PcG) proteins are gene repressors that help to maintain cellular identity during development via chromatin remodeling. Fertilization-independent endosperm (FIE), a member of the PcG complex, operates extensively in plant development, but its role in rice has not been fully investigated to date. We report the isolation and characterization of a PcG member in rice, which was designated OsFIE2 for Oryza sativa Fertilization-Independent Endosperm 2. OsFIE2 is a single-copy gene in the rice genome and shows a universal expression pattern. The OsFIE2 RNAi lines displayed pleiotropic phenotypes in vegetative and reproductive organ generation. In unfertilized lines, endosperm formation could be triggered without embryo formation, which indicates that FIE is indeed involved in the suppression of autonomous endosperm development in rice. Furthermore, lateral root generation was promoted early in the roots of OsFIE2 RNAi lines, whereas the primary root was premature and highly differentiated. As the root tip stem cell differentiated, QHB, the gene required for stem cell maintenance in the quiescent center, was down-regulated. Our data suggest that the OsFIE2-PcG complex is vital for rice reproduction and endosperm formation. Its role in stem cell maintenance suggests that the gene is functionally conserved in plants as well as animals.

  13. Rice Os9BGlu31 Is a Transglucosidase with the Capacity to Equilibrate Phenylpropanoid, Flavonoid, and Phytohormone Glycoconjugates*

    PubMed Central

    Luang, Sukanya; Cho, Jung-Il; Mahong, Bancha; Opassiri, Rodjana; Akiyama, Takashi; Phasai, Kannika; Komvongsa, Juthamath; Sasaki, Nobuhiro; Hua, Yan-ling; Matsuba, Yuki; Ozeki, Yoshihiro; Jeon, Jong-Seong; Cairns, James R. Ketudat

    2013-01-01

    Glycosylation is an important mechanism of controlling the reactivities and bioactivities of plant secondary metabolites and phytohormones. Rice (Oryza sativa) Os9BGlu31 is a glycoside hydrolase family GH1 transglycosidase that acts to transfer glucose between phenolic acids, phytohormones, and flavonoids. The highest activity was observed with the donors feruloyl-glucose, 4-coumaroyl-glucose, and sinapoyl-glucose, which are known to serve as donors in acyl and glucosyl transfer reactions in the vacuole, where Os9BGlu31 is localized. The free acids of these compounds also served as the best acceptors, suggesting that Os9BGlu31 may equilibrate the levels of phenolic acids and carboxylated phytohormones and their glucoconjugates. The Os9BGlu31 gene is most highly expressed in senescing flag leaf and developing seed and is induced in rice seedlings in response to drought stress and treatment with phytohormones, including abscisic acid, ethephon, methyljasmonate, 2,4-dichlorophenoxyacetic acid, and kinetin. Although site-directed mutagenesis of Os9BGlu31 indicated a function for the putative catalytic acid/base (Glu169), catalytic nucleophile residues (Glu387), and His386, the wild type enzyme displays an unusual lack of inhibition by mechanism-based inhibitors of GH1 β-glucosidases that utilize a double displacement retaining mechanism. PMID:23430256

  14. Rice zinc finger protein DST enhances grain production through controlling Gn1a/OsCKX2 expression.

    PubMed

    Li, Shuyu; Zhao, Bingran; Yuan, Dingyang; Duan, Meijuan; Qian, Qian; Tang, Li; Wang, Bao; Liu, Xiaoqiang; Zhang, Jie; Wang, Jun; Sun, Jiaqiang; Liu, Zhao; Feng, Yu-Qi; Yuan, Longping; Li, Chuanyou

    2013-02-19

    The phytohormone cytokinin (CK) positively regulates the activity and function of the shoot apical meristem (SAM), which is a major parameter determining seed production. The rice (Oryza sativa L.) Gn1a/OsCKX2 (Grain number 1a/Cytokinin oxidase 2) gene, which encodes a cytokinin oxidase, has been identified as a major quantitative trait locus contributing to grain number improvement in rice breeding practice. However, the molecular mechanism of how the expression of OsCKX2 is regulated in planta remains elusive. Here, we report that the zinc finger transcription factor DROUGHT AND SALT TOLERANCE (DST) directly regulates OsCKX2 expression in the reproductive meristem. DST-directed expression of OsCKX2 regulates CK accumulation in the SAM and, therefore, controls the number of the reproductive organs. We identify that DST(reg1), a semidominant allele of the DST gene, perturbs DST-directed regulation of OsCKX2 expression and elevates CK levels in the reproductive SAM, leading to increased meristem activity, enhanced panicle branching, and a consequent increase of grain number. Importantly, the DST(reg1) allele provides an approach to pyramid the Gn1a-dependent and Gn1a-independent effects on grain production. Our study reveals that, as a unique regulator of reproductive meristem activity, DST may be explored to facilitate the genetic enhancement of grain production in rice and other small grain cereals.

  15. A rice calcium-dependent protein kinase OsCPK12 oppositely modulates salt-stress tolerance and blast disease resistance.

    PubMed

    Asano, Takayuki; Hayashi, Nagao; Kobayashi, Michie; Aoki, Naohiro; Miyao, Akio; Mitsuhara, Ichiro; Ichikawa, Hiroaki; Komatsu, Setsuko; Hirochika, Hirohiko; Kikuchi, Shoshi; Ohsugi, Ryu

    2012-01-01

    Calcium-dependent protein kinases (CDPKs) regulate the downstream components in calcium signaling pathways. We investigated the effects of overexpression and disruption of an Oryza sativa (rice) CDPK (OsCPK12) on the plant's response to abiotic and biotic stresses. OsCPK12-overexpressing (OsCPK12-OX) plants exhibited increased tolerance to salt stress. The accumulation of hydrogen peroxide (H(2) O(2) ) in the leaves was less in OsCPK12-OX plants than in wild-type (WT) plants. Genes encoding reactive oxygen species (ROS) scavenging enzymes (OsAPx2 and OsAPx8) were more highly expressed in OsCPK12-OX plants than in WT plants, whereas the expression of the NADPH oxidase gene, OsrbohI, was decreased in OsCPK12-OX plants compared with WT plants. Conversely, a retrotransposon (Tos17) insertion mutant, oscpk12, and plants transformed with an OsCPK12 RNA interference (RNAi) construct were more sensitive to high salinity than were WT plants. The level of H(2) O(2) accumulation was greater in oscpk12 and OsCPK12 RNAi plants than in the WT. These results suggest that OsCPK12 promotes tolerance to salt stress by reducing the accumulation of ROS. We also observed that OsCPK12-OX seedlings had increased sensitivity to abscisic acid (ABA) and increased susceptibility to blast fungus, probably resulting from the repression of ROS production and/or the involvement of OsCPK12 in the ABA signaling pathway. Collectively, our results suggest that OsCPK12 functions in multiple signaling pathways, positively regulating salt tolerance and negatively modulating blast resistance.

  16. Hydrogen peroxide overload increases adriamycin-induced apoptosis of SaOS(2)FM, a manganese superoxide dismutase-overexpressing human osteosarcoma cell line.

    PubMed

    Wang, Yadi; Kuroda, Masahiro; Gao, Xian-Shu; Asaumi, Jun-Ichi; Shibuya, Kohichi; Kawasaki, Shoji; Akaki, Shiro; St Clair, Daret; Hiraki, Yoshio; Kanazawa, Susumu

    2005-05-01

    We previously developed a new microscopic observation system that enables time-lapse quantitative analysis of apoptosis and necrosis. With this system we quantitatively analyzed adriamycin (ADR)-induced cell death using manganese superoxide dismutase (MnSOD)- and wild-type p53-gene transfectants on SaOS(2), a p53-deficient human osteosarcoma cell line. A highly MnSOD-overexpressing cell line, SaOS(2)FM(H), acquired ADR-tolerance compared to the parent cell line SaOS(2). The ADR-tolerance of SaOS(2)FM(H) diminished by L-buthionine-[S,R]-sulfoximine (BSO), which did not change ADR-sensitivity of SaOS(2), to the similar ADR-sensitivity of SaOS(2). A wild-type p53-expressing cell line, SaOS(2)wtp53, significantly increased in ADR-sensitivity compared to SaOS(2). This ADR-sensitivity of SaOS(2)wtp53 was enhanced by BSO. When isosorbide 5-mononitrate was combined with BSO, isosorbide 5-mononitrate increased ADR sensitivity of a moderately MnSOD-overexpressing cell line, SaOS(2)FM(L), decreased that of SaOS(2) FM(H), and did not change those of SaOS(2) and SaOS(2)wtp53 compared to BSO alone. Time-lapse microscopic observations during ADR treatment for 24 h indicated that the most cells of each cell line underwent apoptosis, and a few cells (less than 11%) died by necrosis. When cells were treated with iso-concentration of ADR, apoptosis of SaOS(2)FM(H) was less than that of SaOS(2). BSO, which did not change ADR-sensitivity of SaOS(2), increased appearance rate of ADR-induced apoptosis, but not necrosis of MnSOD-overexpressing cell lines. When iso-survival dose of ADR, which reduced surviving fraction to 0.01, was given for each cell line, no difference was observed in appearance of either apoptosis or necrosis between SaOS(2) and MnSOD-overexpressing cell lines. On the other hands, appearance of both apoptosis and the following secondary necrosis of SaOS(2) wtp53 was significantly accelerated compared to those of SaOS(2). These findings indicate that hydrogen peroxide

  17. Mechanistic control of product selectivity. Reactions between cis-/trans cis-/trans-[OsVI(tpy)(Cl)2(N)]+ and triphenylphosphine sulfide.

    PubMed

    Huynh, M H; White, P S; Meyer, T J

    2000-06-26

    Reactions between the Os(VI)-nitrido complexes cis- and trans-[Os(VI)(tpy)(Cl)2(N)]+ (tpy is 2,2':6',2"-terpyridine) and triphenylphosphine sulfide, SPPh3, give the corresponding Os(IV)-phosphoraniminato, [Os(IV)(tpy)(Cl)2(NPPh3)]+, and Os(II)-thionitrosyl, [Os(II)(tpy)(Cl)2(NS)]+, complexes as products. The Os-N bond length and Os-N-P angle in cis-[Os(IV)(tpy)(Cl)2(NPPh3)](PF6) are 2.077(6) A and 138.4(4) degrees. The rate law for formation of cis- and trans-[Os(IV)(tpy)(Cl)2(NPPh3)]+ is first order in both [Os(VI)(tpy)(Cl)2(N)]+ and SPPh3 with ktrans(25 degrees C, CH3CN) = 24.6 +/- 0.6 M(-1) s(-1) and kcis(25 degrees C, CH3CN) = 0.84 +/- 0.09 M(-1) s(-1). As found earlier for [Os(II)(tpm)(Cl)2(NS)]+, both cis- and trans-[Os(II)(tpy)(Cl)2(NS)]+ react with PPh3 to give [Os(IV)(tpy)(Cl)2(NPPh3)]+ and SPPh3. For both complexes, the reaction is first order in each reagent with ktrans(25 degrees C, CH3CN) = (6.79 +/- 0.08) x 10(2) M(-1) s(-1) and kcis(25 degrees C, CH3CN) = (2.30 +/- 0.07) x 10(2) M(-1) s(-1). The fact that both reactions occur rules out mechanisms involving S atom transfer. These results can be explained by invoking a common intermediate, [Os(IV)(tpy)(Cl)2(NSPPh3)]+, which undergoes further reaction with PPh3 to give [Os(IV)(tpy)(Cl)2(NPPh3)]+ and SPPh3 or with [Os(VI)(tpy)(Cl)2(N)]+ to give [Os(IV)(tpy)(Cl)2(NPPh3)]+ and [Os(II)(tpy)(Cl)2(NS)]+.

  18. OsPIN5b modulates rice (Oryza sativa) plant architecture and yield by changing auxin homeostasis, transport and distribution.

    PubMed

    Lu, Guangwen; Coneva, Viktoriya; Casaretto, José A; Ying, Shan; Mahmood, Kashif; Liu, Fang; Nambara, Eiji; Bi, Yong-Mei; Rothstein, Steven J

    2015-09-01

    Plant architecture attributes such as tillering, plant height and panicle size are important agronomic traits that determine rice (Oryza sativa) productivity. Here, we report that altered auxin content, transport and distribution affect these traits, and hence rice yield. Overexpression of the auxin efflux carrier-like gene OsPIN5b causes pleiotropic effects, mainly reducing plant height, leaf and tiller number, shoot and root biomass, seed-setting rate, panicle length and yield parameters. Conversely, reduced expression of OsPIN5b results in higher tiller number, more vigorous root system, longer panicles and increased yield. We show that OsPIN5b is an endoplasmic reticulum (ER) -localized protein that participates in auxin homeostasis, transport and distribution in vivo. This work describes an example of an auxin-related gene where modulating its expression can simultaneously improve plant architecture and yield potential in rice, and reveals an important effect of hormonal signaling on these traits.

  19. Coupled Nd and B' spin ordering in the double perovskites Nd2NaB'O6 (B' = Ru, Os)

    SciTech Connect

    Aczel, Adam A; Bugaris, Dan; Yeon, Jeongho; Dela Cruz, Clarina R; Zur Loye, Hans-Conrad; Nagler, Stephen E

    2013-01-01

    We present a neutron powder diffraction study of the monoclinic double perovskite systems Nd$_2$NaB$'$O$_6$ (B$'$~$=$~Ru, Os), with magnetic atoms occupying both the A and B$'$ sites. Our measurements reveal coupled spin ordering between the Nd and B$'$ atoms with magnetic transition temperatures of 14~K for Nd$_2$NaRuO$_6$ and 16~K for Nd$_2$NaOsO$_6$. There is a Type I antiferromagnetic structure associated with the Ru and Os sublattices, with the ferromagnetic planes stacked along the c-axis and [110] direction respectively, while the Nd sublattices exhibit complex, canted antiferromagnetism with different spin arrangements in each system.

  20. Distance dependence of intrahelix Ru(II)* to Os(II) polypyridyl excited-state energy transfer in oligoproline assemblies.

    PubMed

    Brennaman, M Kyle; Fleming, Cavan N; Slate, Cheryl A; Serron, Scafford A; Bettis, Stephanie E; Erickson, Bruce W; Papanikolas, John M; Meyer, Thomas J

    2013-05-30

    Energy transfer between the metal-to-ligand charge transfer (MLCT) excited states of [Pra [M(II)(bpy)2(4-Me-4'(-N(H)CO)bpy)](PF6)2 units ([Pra(M(II)bpy2(mbpy)](2+): M(II) = Ru(II) or Os(II), bpy = 2,2'-bipyridine, mbpy = 4'-methyl-2,2'-bipyridine-4-carboxamido, Pra = 4-M(II)-L-proline) linked covalently to oligoproline assemblies in room temperature acetonitrile occurs on the picosecond-nanosecond time scale and has been time-resolved by transient emission measurements. Three derivatized oligoprolines, [CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro2-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro2-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro6-Glu-NH2](6+) (ORR-2, Pro = L-proline and Glu = glutamic acid); [CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro3-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro3-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro6-Glu-NH2](6+) (ORR-3); and CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro5-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro5-Pra[Ru(II)(bpy)2(mbpy)](2+)Pro6-Glu2-NH2](6+) (ORR-5), were prepared by using solid-phase peptide synthesis. Given the helical nature of the resulting assemblies and the nature of the synthesis, composition, length, and loading pattern are precisely controlled in the assemblies. In acetonitrile, they adopt a proline I helical secondary structure, confirmed by circular dichroism, in which the appended chromophores are ordered in well-defined orientations and internuclear separation distances although helix formation for ORR-2 is incomplete. Quantitative comparison of oligoproline ground-state absorption and steady-state emission spectra to those for the constituents, [Boc-Pra[M(II)(bpy)2(mbpy)](2+)-OH](PF6)2 (Boc = N(α)-(1,1-dimethylethoxycarbonyl), shows that following Ru(II) light absorption, Ru(II)* undergoes facile energy transfer resulting in sensitization of Os(II). Sensitization efficiencies are 93% for ORR-2, 77% for ORR-3, and 73% for ORR-5. Picosecond-resolved emission measurements reveal complex, coupled dynamics that arise from excited-state decay and kinetically

  1. Chemical bonding analysis and properties of La{sub 7}Os{sub 4}C{sub 9}-A new structure type containing C- and C{sub 2}-units as Os-coordinating ligands

    SciTech Connect

    Dashjav, Enkhtsetseg; Prots, Yurii; Kreiner, Guido; Schnelle, Walter; Wagner, Frank R. Kniep, Ruediger

    2008-11-15

    The new ternary carbide La{sub 7}Os{sub 4}C{sub 9} was prepared by argon arc-melting of the elements followed by subsequent heat treatment at 900 deg. C for 250 h. The compound crystallizes monoclinic, in the space group C2/m (a=1198.5(2) pm, b=542.0(1) pm, c=1196.2(2) pm, {beta}=111.04(1){sup o}, V=725.2(2)x10{sup 6} pm{sup 3}, Z=2). The structure was determined from single crystal X-ray diffraction data and refined to a residual of R{sub 1}=0.02 (wR{sub 2}=0.03) for 4812 unique reflections and 64 variable parameters. Electrical resistivity and magnetic susceptibility measurements characterize the compound as a Pauli-paramagnetic metal. The crystal structure contains bridging C- and terminal C{sub 2}-units as Os-coordinating ligands, thereby forming polyanions {sub {infinity}}{sup 1}[Os{sub 4}(C{sub 2}){sub 2}C{sub 5}] running along the [101] direction. The polyanions are composed of alternating Os(C{sub 2})C{sub 2} and OsC{sub 3} units with the transition metal in distorted trigonal planar coordination. Charge compensation is ensured by La cations which are situated in-between the polyanions. The carbon-carbon bond (131 pm) within the C{sub 2} pairs is slightly shorter than the value of a common C-C double bond, and is discussed on the basis of COHP curves on the one side, and with ELI-D and electron density distributions on the other side. The method of partial ELI-D decomposition is shown to be well suited for the characterization of separated DOS structures in terms of chemical bonding signatures provided by ELI-D. The Os-La interactions are shown to be of a polar multicenter-bonding type with Os playing the role of the electron donor. Compared to an acetylide the C{sub 2} species were found to possess a significantly reduced bond order and an enhanced number of electrons in lone pair type spatial regions. This type of species cannot be simply classified in terms of model pictures such as C{sub 2}{sup 2-} and C{sub 2}{sup 4-}, respectively. - Graphical

  2. Molecular Characterization of Rice OsLCB2a1 Gene and Functional Analysis of its Role in Insect Resistance</