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Sample records for entre os mapuche

  1. Renal transplantation in Mapuche people.

    PubMed

    Ardiles, R; Beltrán, R; Jerez, V; Droguett, M A; Mezzano, S; Ardiles, L

    2008-04-01

    Previous studies have demonstrated higher concentrations of some histocompatibility antigens in Mapuche people compared with non-Mapuche Chileans in the renal transplantation program. With the aim of evaluating whether those antigenic differences might induce differences in the outcomes of renal transplantation among patients belonging to that ethnic group, we reviewed HLA studies and at least 6 months follow-up of all patients with a first kidney transplant between 1980 and 2006. The 248 patients had a mean age of 37.6 years, 40% were females, and 48% had living related donors. The mean kidney follow-up was 90 months and patient follow-up was 106 months. Thirty-nine patients (16%) were classified as Mapuche, according to their surnames, including 16 women with overall mean age of 34.5 years, and 14 had been transplanted from a living related donor. Mapuche patients received organs with better HLA matching expressed as number of identities (3.4 +/- 0.1 versus 2.8 +/- 0.1 among non-Mapuche; P < .05), and the proportion receiving organs with > or = 3 compatibilities was significantly higher (Mapuche 38% versus non-Mapuche 22%; P < .05). Kaplan-Meier survival curves showed nonsignificant differences in kidney survival: 86% at 5 years and 68% at 10 years in Mapuche; and 83% and 65%, respectively, for non-Mapuche. Patient survival rates were 97% at 5 years and 86% at 10 years in the Mapuche group versus 91% and 79%, respectively, in the non-Mapuche group; both results were not significantly different. Our results showed similar outcomes of kidney and patient survivals among Mapuche people even when they received organs with better HLA matches. PMID:18454999

  2. 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

  3. An Environmental Management Model of Thermal Waters in Entreos 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 Entreos 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

  4. HIV Issues and Mapuches in Chile.

    PubMed

    Cianelli, Rosina; Ferrer, Lilian; Cabieses, Báltica; Araya, Alejandra; Matsumoto, Cristina; Miner, Sarah

    2008-01-01

    Chile is a country with an incipient HIV epidemic. Just as in other countries, disadvantaged groups in Chile are contributing to the increased incidence of the disease. The Mapuche indigenous population is one such group that has been affected by the spread of HIV. However, no prevention programs are tailored to the culturally specific needs of this community. In recognition of this discrepancy, an academic-community partnership was formed to develop an HIV educational module for a Mapuche community. The module was developed for use as part of an already established health-related program. The aims of the module were to identify perceptions about HIV among Mapuches and present information specific to HIV and its prevention. Focus was placed on cultural sensitivity. A total of 16 Mapuches participated voluntarily and showed some knowledge regarding HIV, but they lacked an overall understanding as to how it is transmitted and why prevention strategies are effective. Continued collaboration between academia and affected communities as well as incorporating HIV information into established programs are effective strategies for delivering prevention information to disadvantaged populations and for further understanding their perceptions and health care needs. PMID:18457766

  5. HIV ISSUES AND MAPUCHES IN CHILE

    PubMed Central

    Cianelli, Rosina; Ferrer, Lilian; Cabieses, Báltica; Araya, Alejandra; Matsumoto, Cristina; Miner, Sarah

    2015-01-01

    Chile is a country with an incipient HIV epidemic. Just as in other countries, disadvantaged groups in Chile are contributing to the increased incidence of the disease. The Mapuche indigenous population is one such group that has been affected by the spread of HIV. However, no prevention programs are tailored to the culturally specific needs of this community. In recognition of this discrepancy, an academic-community partnership was formed to develop an HIV educational module for a Mapuche community. The module was developed for use as part of an already established health-related program. The aims of the module were to identify perceptions about HIV among Mapuches and present information specific to HIV and its prevention. Focus was placed on cultural sensitivity. The module was carried out in connection with a first-aid course in an attempt to increase effectiveness of the intervention by working jointly with an established community program. Sixteen (16) Mapuches participated voluntarily and demonstrated some knowledge regarding HIV, but they lacked an overall understanding as to how it is transmitted and why prevention strategies are affective. Participants correctly identified sexual contact as a means of transmission, but when asked why, one person stated, “I just know it, I read it.” There were significant barriers to communication within the group, secondary to cultural practices related to age and gender. Major obstacles in controlling HIV are the lack of prevention strategies targeted to disadvantaged groups. The module developed for this intervention was the first effort of the Academic Community Partnership established between the Pontificia Universidad Católica de Chile and the Mapuche group around HIV prevention. Continued collaboration between academia and affected communities as well as incorporating HIV information into established programs are effective strategies for delivering prevention information to disadvantaged populations and for

  6. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    PubMed Central

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H2O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H2O) were substantial and confirmed by inhibition of platelet surface activation markers. PMID:22028732

  7. Mapuche herbal medicine inhibits blood platelet aggregation.

    PubMed

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers. PMID:22028732

  8. Becoming "Neuquino" in Mapuzugun: Teaching Mapuche Language and Culture in the Province of Neuquen, Argentina

    ERIC Educational Resources Information Center

    Szulc, Andrea

    2009-01-01

    This article explores the sense of belonging promoted by the current program of Educacion Intercultural Bilingue (EIB) of the province of Neuquen for Mapuche children, examining the design and implementation of this program. The analysis reveals how this program reinforces a hegemonic definition of Mapuche identity, which relegates Mapuche culture…

  9. Gastroprotective effect of the Mapuche crude drug Araucaria araucana resin and its main constituents.

    PubMed

    Schmeda-Hirschmann, Guillermo; Astudillo, Luis; Rodríguez, Jaime; Theoduloz, Cristina; Yáñez, Tania

    2005-10-01

    The resin from the tree Araucaria araucana (Araucariaceae) has been used since pre-columbian times by the Mapuche amerindians to treat ulcers. The gastroprotective effect of the resin was assessed in the ethanol-HCl-induced gastric ulcer in mice showing a dose-dependent gastroprotective activity at 100, 200 and 300 mg/kg per os. The main three diterpene constituents of the resin, namely imbricatolic acid, 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid were isolated and evaluated for gastroprotective effect at doses of 50, 100 and 200 mg/kg. A dose-related gastroprotective effect with highly significant activity (P<0.01) was observed at doses up to 200 mg/kg. At 100 mg/kg, the highest gastroprotective activity was provided by 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of the main diterpenes as well as lansoprazole was studied towards human lung fibroblasts (MRC-5) and determined by the MTT reduction assay. A concentration-dependent cell viability inhibition was found with IC50 values ranging from 125 up to 290 microM. Our results support the traditional use of the Araucaria araucana resin by the Mapuche culture. PMID:15985351

  10. Soil Quality Indicators to Define Land Use in the Area of Native Forest of Entreos, Argentina

    NASA Astrophysics Data System (ADS)

    Wilson, M. G.; Tasi, H. A.; Paz González, A.; Díaz, E. L.; Sasal, M. C.

    2012-04-01

    The main economic activity in the area of native forest of the province of Entreos (Argentina) has long been the agricultural and/or livestock production, especially cattle breeding. In recent years, the proportion of agricultural crops in the rotations, especially that of soybean, has increased, thus leading to an increase in the need for land clearing to incorporate new lands for agricultural use. Most of these lands are considered marginal for agricultural use. In addition rice farming with irrigation is a critical part of the Entreos economy. Defining and assessing soil quality indicators (SQI) that show the evolution of the soil with different uses and management systems is a way to contribute to the knowledge of soil quality. The aims of this study were to characterize the current land use and land tenure in the area of native forest of Entreos, as well as to identify and select variables sensitive to agricultural and/or livestock use of the most representative soils of this area (indicators of the dynamic quality of the soil) and define the most appropriate land use according to land suitability and behavior of these indicators. We identified the most representative soil subgroups (corresponding to the orders Vertisols, Mollisols and Alfisols) and defined the production systems livestock-agricultural, agricultural-livestock, agricultural without irrigation, and rice crop irrigated with water from groundwater and surface reservoirs. We also determined the physical, physico-chemical, chemical and microbiological variables of the soil, and characterized the quality of the water for irrigation. We selected the SQI using Principal Components Analysis, to form a minimum data set (MDS). The change in the use of the land responded to a favorable economic situation for agriculture that started in the 1990's. The leasing and sharecropping schemes and the incidental contracts have become increasingly important, predominating over the undivided property. We

  11. State of Conservation of the Native Forests in Entreos (Argentina) and Changes in Land Use

    NASA Astrophysics Data System (ADS)

    Sabattini, R. A.; Sione, S. M.; Ledesma, S. G.; Sabattini, J. A.; Wilson, M. G.

    2012-04-01

    The native forest area of Entreos province (Argentina) is associated with a constant change in land use, with an increase in recent years in agricultural use, especially for soybean crop. In addition, since its inadequate management has triggered degradation processes of the natural forest structure, the implementation of strategies for the restoration and conservation of native forests has become a priority. The aim of this study was to diagnose the conservation state of the native forest in the basin of the Estacas Stream (Entreos, Argentina) after the change in land use, to help design guidelines for the restoration and sustainable management of these ecosystems. The field study was conducted in October 2010, in a representative area of the native forest of 73,000 ha. Using Landsat 5-TM images (INPE), environments were separated by manual vectorization, identifying and classifying native forests and other lands (agricultural, urban). Using a field exploratory survey (58 geo-referenced sampling points), we developed patterns corresponding to the different types of forests, contrasting this information with the digital data of the images. The native forests were classified according to type (high/low forest, open/closed forest, savanna), successional stage (climax, successional or regeneration forest) and degree of disturbance (weed growth, erosion, fire), and their frequency determined. Each classification was assessed by a contingency matrix, and global reliability index and the Kappa index. The information obtained generated a classification map of native forests in the basin scale. We found that the native forest covered an area of 42,726.91 ha, accounting for 58.52% of the total basin area, and that the rest corresponded to other land uses. The most frequent native forests (59.09%) were climax forest, but accounted for only 8.2% of the basin area. Within this group, the most important were the low and open forest, with Prosopis affinis and Prosopis

  12. Maria Catrileo's Work in the Tagmemics of Mapuche.

    ERIC Educational Resources Information Center

    Hernandez, Frances

    The Mapuches, a tribe now numbering about 500,000 people in south central Chile are the descendants of the Araucanians of Spanish legend. Many still speak only their own idiom, which now shows much lexical influence of the surrounding Spanish. This paper is an exposition of Maria Catrileo Chiguailaf de Godo's research in her native language. It…

  13. Negotiating Neoliberal Multiculturalism: Mapuche Workers in the Chilean State

    ERIC Educational Resources Information Center

    Park, Yun-Joo; Richards, Patricia

    2007-01-01

    A central component of neoliberal multiculturalism in contemporary Latin America is an increase in indigenous individuals who work for the state, implementing indigenous policy at the municipal, regional and national levels. We explore the consequences of the inclusion of these individuals by analyzing the experiences of Mapuche state workers in…

  14. Human leukocyte antigens in indigenous (mapuche) people in a regional renal transplantation program in chile.

    PubMed

    Droguett, M A; Oyarzún, M J; Alruiz, P; Jerez, V; Mezzano, S; Ardiles, L

    2005-10-01

    An active regional transplantation program established in the southern region of Chile has allowed the incorporation of ethnic minorities particularly Mapuche living in this geographic area in the development of a histocompatibility database. To identify possible differences in the human leukocyte (HLA) antigen distribution in Chilean Mapuche compared with non-Mapuche, we reviewed 442 HLA tissue-typing studies. Seventy-eight of 309 recipients (25%) and 18 of 133 donors (13%) were Mapuche. Among recipients, Mapuche people showed a significantly higher frequency of the HLA antigens, A28, B16, DR4, and DR8, and a lower one for A19, B15, and DR1 (P < .05) compared with non-Mapuche individuals. A particularly higher frequency of the haplotype A28, -B16, -DR4 was also evidenced in Mapuche. Besides, these recipients showed a higher frequency of the allele -DR4 when compared with Mapuche donors. A greater frequency of some histocompatibility antigens in patients with chronic renal disease might be attributed to allelic concentration due to a high index of endogamy, but a possible association with the development of progressive renal disease cannot be ignored, especially when a higher prevalence of DR4 was observed among Mapuche recipients. PMID:16298598

  15. HLA genetic profile of Mapuche (Araucanian) Amerindians from Chile.

    PubMed

    Rey, Diego; Parga-Lozano, Carlos; Moscoso, Juan; Areces, Cristina; Enriquez-de-Salamanca, Mercedes; Fernández-Honrado, Mercedes; Abd-El-Fatah-Khalil, Sedeka; Alonso-Rubio, Javier; Arnaiz-Villena, Antonio

    2013-07-01

    Amerindian Mapuche (Araucanians) are now living in Chile and Argentina at both sides of Andean Mountains. They are anthropologically and genetically different from southernmost South America Patagonian Amerindians. Most of the HLA alleles found in our Mapuche sample are frequent or very frequent in North and South America Amerindians: (1) Class I: A*02:01, A*03:01, A*68:01, B*39:09, B*51:01, (2) Class II: DRB1*03:01, DRB1*04:03, DRB1*07:01, DRB1*08:02, DRB1*14:02, DRB1*16:02. One of the nine most frequent extended haplotypes seems to be from European origin, suggesting the existence of a degree of admixture with Europeans in our Mapuche sample. It has been calculated of about 11 % admixture. Three of the extended haplotypes are also found in other Amerindians and five of them are newly found in Mapuche Amerindians: A*68:01-B*39:09-DRB1*08:02-DQB1*04:02; A*68:01-B*51:01-DRB1*04:03-DQB1*03:02; A*29:01-B*08:01-DRB1*03:01-DQB1*02:01; A*02:01-B*15:01-DRB1*04:03-DQB1*03:02; A*33:01-B*14:02-DRB1*07:01-DQB1*03:03. The medical importance of calculating HLA profile is discussed on the diagnostic (HLA and disease) and therapeutical bases of HLA pharmacogenomics and on the construction of a virtual transplantation HLA list profile. Also, anthropological conclusions are drawn. PMID:23666052

  16. Mapudungun According to Its Speakers: Mapuche Intellectuals and the Influence of Standard Language Ideology

    ERIC Educational Resources Information Center

    Lagos, Cristián; Espinoza, Marco; Rojas, Darío

    2013-01-01

    In this paper, we analyse the cultural models (or folk theory of language) that the Mapuche intellectual elite have about Mapudungun, the native language of the Mapuche people still spoken today in Chile as the major minority language. Our theoretical frame is folk linguistics and studies of language ideology, but we have also taken an applied…

  17. Origins of the Discrimination Perceived by Mapuches in Chile Based on an Evaluation of Kimeltuwun

    ERIC Educational Resources Information Center

    Rapiman, Daniel Quilaqueo

    2011-01-01

    The aim of this article is to examine the origin of perceived discrimination as it appears in the discourse of Mapuches living in Temuco and Santiago, and how that discourse is related to the evaluation of "kimeltuwun" (educational knowledge). A qualitative design was used to survey Mapuche emigrants to these two urban centers, where most of them…

  18. [Food satisfaction in Mapuche persons in the Metropolitan Region of Santiago, Chile].

    PubMed

    Schnettler, Berta; Miranda, Horacio; Sepúlveda, José; Denegri, Marianela; Mora, Marcos; Lobos, Germán

    2011-06-01

    Although the study and measurement of satisfaction with life has generated great interest in the last 15 years, there are few works which address satisfaction with food-related life. In order to identify variables which have an influence on satisfaction with food-related life among Mapuche persons, a survey was applied to 400 Mapuche subjects in the Santiago Metropolitan Region, Chile. The scales evaluated in the questionnaire included: SWFL (Satisfaction with Food-related Life), lifestyles, food, and Mapuche acculturation. It was found that 41.0% were extremely satisfied, 40.5% satisfied, 17.2% somewhat satisfied and 1.2% dissatisfied with their food-related life. To identify variables which have an influence on satisfaction with food, an ordinal multinomial logit model was proposed, which was significant (p < 0.01) as a whole. The probability of high satisfaction with food-related life increases as there are fewer children in the household, the person's expenditure on food increases, the person consumes some Mapuche foods, is aged 55 or more, consumes red meat in moderation, consumes foods without additives, try to balance work and private life, does not read the labels of products, and if he/she had Mapuche friends at school. Thus satisfaction with food-related life in Mapuche persons in the Metropolitan Region is related to demographic variables, expenditure on food, consumption of Mapuche foods and life-style. PMID:22308944

  19. Cutaneous fistula due to pulmonary actinomycosis in a Mapuche girl.

    PubMed

    Briceño, Gaston; Guzman, Pablo; Schafer, Fabiola

    2013-01-01

    Actinomycosis is a chronic granulomatous disease caused by Gram-positive anaerobic bacteria of the genus Actinomyces. Pulmonary actinomycosis is a rare infection in children, and its extension into the chest wall is infrequently reported. We report a case of pulmonary actinomycosis in a 14-year-old girl of Mapuche descent who presented with chronic respiratory symptoms and multiple discharging skin sinuses on her right lower chest wall. The diagnosis was made by skin biopsy, which showed sulfur granules with actinomyces colonies. She was successfully treated with intravenous ceftriaxone and penicillin G for 6 weeks, followed by oral amoxicillin for 6 months. PMID:23488542

  20. Genetic variants of serum butyrylcholinesterase in Chilean Mapuche Indians.

    PubMed

    Acuña, M; Eaton, L; Ramírez, N R; Cifuentes, L; Llop, E

    2003-05-01

    We estimated the frequencies of serum butyrylcholinesterase (BChE) alleles in three tribes of Mapuche Indians from southern Chile, using enzymatic methods, and we estimated the frequency of allele BCHE*K in one tribe using primer reduced restriction analysis (PCR-PIRA). The three tribes have different degrees of European admixture, which is reflected in the observed frequencies of the atypical allele BCHE*A: 1.11% in Huilliches, 0.89% in Cuncos, and 0% in Pehuenches. This result is evidence in favor of the hypothesis that BCHE*A is absent in native Amerindians. The frequencies of BCHE*F were higher than in most reported studies (3.89%, 5.78%, and 4.41%, respectively). These results are probably due to an overestimation of the frequency of allele BCHE*F, since none of the 20 BCHE UF individuals (by the enzymatic test) individuals analyzed showed either of the two DNA base substitutions associated with this allele. Although enzymatic methods rarely detect the presence of allele BCHE*K, PCR-PIRA found the allele in an appreciable frequency (5.76%), although lower than that found in other ethnic groups. Since observed frequencies of unusual alleles correspond to estimated percentages of European admixture, it is likely that none of these unusual alleles were present in Mapuche Indians before the arrival of Europeans. PMID:12687586

  1. [Mucolipidoses type IV in a patient with mapuche ancestry].

    PubMed

    Hernández Ch, Marta; Méndez C, José Ignacio; Concha G, María José; Huete L, Isidro; González B, Sergio; Durán S, Gloria P

    2008-07-01

    We report a 7 year-old girl with mapuche ancestors, diagnosed as a cerebral palsy since infancy and on active rehabilitation. She acquired motor and cognitive skills at 3 years of age. At 5 years of age, a slow neurological deterioration started, associated to visual impairment. Optic atrophy was added to the typical neurological exam of ataxic cerebral palsy and the diagnosis was re-considered. Neuroimaging showed a slow and progressive atrophy of intracerebral structures and ultramicroscopy revealed intracytoplasmatic inclusions in conjunctiva and skin, compatible with mucolipidoses type IV (ML-IV). ML-IV must be included in the differential diagnosis of cerebral palsy associated with loss of acquired skills and progressive visual impairment. Electron microscopy of skin or conjunctiva is a useful diagnostic test. Suspicion of ML-IV must not be restricted to Ashkenazi Jewish population. PMID:18949166

  2. Indigenous Knowledge and Language: Decolonizing Culturally Relevant Pedagogy in a Mapuche Intercultural Bilingual Education Program in Chile

    ERIC Educational Resources Information Center

    Ortiz, Patricio R.

    2009-01-01

    This article illustrates how Mapuche Indigenous knowledge (Kimun) and language (Mapudungun) incorporated into an Intercultural Bilingual Education (IBE) program of a school within a Mapuche context in Chile creates decolonizing counter-hegemonic narratives as forms of culturally relevant pedagogy. Based on a six-month school ethnography, this…

  3. Prevalence of type 2 diabetes and obesity in rural Mapuche population from Chile.

    PubMed

    Pérez-Bravo, F; Carrasco, E; Santos, J L; Calvillán, M; Larenas, G; Albala, C

    2001-03-01

    The aim of this study was to estimate the prevalence of Type 2 diabetes, impaired glucose tolerance (IGT), and obesity in the Mapuche natives from rural areas in Chile. This cross-sectional study involved men (n = 95) and women (n = 224) older than 20 y from an aboriginal ethnic group (Mapuches), residing in rural communities from the south of Chile. Prevalence of Type 2 diabetes and IGT was calculated according to the World Health Organization criteria. Data on age, degree of ancestral purity, obesity, and hypertension were also obtained. The prevalence of Type 2 diabetes in rural Mapuche natives was estimated as 3.2% (95% CI: 0.7--9.0) in men and 4.5% (95% CI: 2.2--8.1) in women. The overall prevalence of obesity was 56.1% (95% CI: 50.5--61.6): 40.0% (95% CI: 30.1--40.8) in men and 62.9% (95% CI: 56.3--69.3) in women (P value < 0.001). These data suggest that the prevalence of obesity and Type 2 diabetes has been increasing during recent years in the Mapuche communities. The prevalence estimated in this study is higher than that reported 15 y ago. This suggests an important role of lifestyle changes as a possible explanation for epidemiologic transition. PMID:11312066

  4. Categorisation of Mapuche Ways of Conceiving Time and Space: Educational Knowledge of the "Kimches"

    ERIC Educational Resources Information Center

    Quilaqueo, Daniel; Torres, Hector

    2013-01-01

    The object of this article is to present a categorisation of the ways in which time and space are conceived in the rationale of Mapuche family education. This approach considers knowledge of natural, social, and cultural elements that characterise the classification of time and space by "kimches" (sages) in the education of children and…

  5. Lactase persistence and dairy intake in Mapuche and Mestizo populations from southern Chile.

    PubMed

    Fernández, Catalina I; Flores, Sergio V

    2014-11-01

    Lactase persistence (LP) occurs at a very low frequency in indigenous populations from Latin America, offering an opportunity to understand the relationship between this genetic trait and patterns of dairy consumption. Here, the frequency of LP is analyzed from Mapuche and -an adjacent- mestizo population inhabiting the Araucanía region. In addition to genotyping for LP, participants were surveyed in relation to general perception and consumption habits of dairy products. Low LP frequency (10%) and very low dairy intake was found among the Mapuche population as compared with Mestizo populations inhabiting Chile. The survey reported that the main reasons for avoidance of dairy were the gastrointestinal symptoms after dairy intake and cultural dietary habits. The interaction between low LP genotype frequency, low dairy intake, and sociocultural determinants is here discussed in the light of their potential health outcomes. PMID:25137143

  6. Putting the market in its place: food security in three Mapuche communities in southern Chile.

    PubMed

    Clark, Timothy David

    2011-01-01

    This article analyzes the impact of state policies since the 1970s on household food security in several Mapuche communities in the Araucanía region of Chile (Region IX). The author highlights key transformations in the national economy and food system and endeavors to link those to local phenomena, in particular the absorption of the local livelihood strategies and food systems into capitalist markets and the high incidences of food insecurity. The article concludes that a reconceptualization of macroeconomic and indigenous policies are required to rebuild the material and social foundations of rural Mapuche communities that provide the bases from which their inhabitants can reconstruct a mutually beneficial relationship with the broader Chilean society and avert the continued acceleration of tension and violence. PMID:22069808

  7. Endogenous retrovirus EAV-HP linked to blue egg phenotype in Mapuche fowl.

    PubMed

    Wragg, David; Mwacharo, Joram M; Alcalde, José A; Wang, Chen; Han, Jian-Lin; Gongora, Jaime; Gourichon, David; Tixier-Boichard, Michèle; Hanotte, Olivier

    2013-01-01

    Oocyan or blue/green eggshell colour is an autosomal dominant trait found in native chickens (Mapuche fowl) of Chile and in some of their descendants in European and North American modern breeds. We report here the identification of an endogenous avian retroviral (EAV-HP) insertion in oocyan Mapuche fowl and European breeds. Sequencing data reveals 100% retroviral identity between the Mapuche and European insertions. Quantitative real-time PCR analysis of European oocyan chicken indicates over-expression of the SLCO1B3 gene (P<0.05) in the shell gland and oviduct. Predicted transcription factor binding sites in the long terminal repeats (LTR) indicate AhR/Ar, a modulator of oestrogen, as a possible promoter/enhancer leading to reproductive tissue-specific over-expression of the SLCO1B3 gene. Analysis of all jungle fowl species Gallus sp. supports the retroviral insertion to be a post-domestication event, while identical LTR sequences within domestic chickens are in agreement with a recent de novo mutation. PMID:23990950

  8. Endogenous Retrovirus EAV-HP Linked to Blue Egg Phenotype in Mapuche Fowl

    PubMed Central

    Alcalde, José A.; Wang, Chen; Han, Jian-Lin; Gongora, Jaime; Gourichon, David; Tixier-Boichard, Michèle; Hanotte, Olivier

    2013-01-01

    Oocyan or blue/green eggshell colour is an autosomal dominant trait found in native chickens (Mapuche fowl) of Chile and in some of their descendants in European and North American modern breeds. We report here the identification of an endogenous avian retroviral (EAV-HP) insertion in oocyan Mapuche fowl and European breeds. Sequencing data reveals 100% retroviral identity between the Mapuche and European insertions. Quantitative real-time PCR analysis of European oocyan chicken indicates over-expression of the SLCO1B3 gene (P<0.05) in the shell gland and oviduct. Predicted transcription factor binding sites in the long terminal repeats (LTR) indicate AhR/Ar, a modulator of oestrogen, as a possible promoter/enhancer leading to reproductive tissue-specific over-expression of the SLCO1B3 gene. Analysis of all jungle fowl species Gallus sp. supports the retroviral insertion to be a post-domestication event, while identical LTR sequences within domestic chickens are in agreement with a recent de novo mutation. PMID:23990950

  9. Ethnic Discrimination against Mapuche Students in Urban High Schools in the Araucanía Region, Chile

    ERIC Educational Resources Information Center

    Becerra, Sandra; Merino, María Eugenia; Mellor, David

    2015-01-01

    Ethnic or racial discrimination towards children and adolescents at schools is of concern in many contexts around the world because it is associated with diverse psychosocial, behavioural, emotional, and identity problems. The purpose of this study was to identify the types of ethnic discrimination experienced by indigenous Mapuche adolescents in…

  10. Medicinal wild plant knowledge and gathering patterns in a Mapuche community from North-western Patagonia.

    PubMed

    Estomba, Diego; Ladio, Ana; Lozada, Mariana

    2006-01-01

    Medicinal plant use has persisted as a long standing tradition in the Mapuche communities of Southern Argentina and Chile. An ethnobotanical survey was conducted in the rural Curruhuinca community located near the mountain city of San Martin de los Andes, Argentina. Semi-structured interviews were carried out on 22 families in order to examine the present use of medicinal plants and their reputed therapeutic effects. Ecological variables, such as distance to the gathering site and biogeographical origin were also analyzed. Our results showed that the Curruhuinca dwellers cited 89 plant species for medicinal purposes, both of native and exotic origin. They know about 47 native plants, of which they use 40, and they know of 42 exotic medicinal plants of which they use 34. A differential pattern was observed given that only native species, relevant for the traditional Mapuche medicine, were collected at more distant gathering sites. The interviewees mentioned 268 plant usages. Those most frequently reported had therapeutic value for treating digestive ailments (33%), as analgesic/anti-inflammatory (25%) and antitusive (13%). Native species were mainly cited as analgesics, and for gynecological, urinary and "cultural syndrome" effects, whereas exotic species were mainly cited for digestive ailments. The total number of medicinal plants known and used by the interviewees was positively correlated with people's age, indicating that this ancient knowledge tends to disappear in the younger generations. PMID:16157460

  11. A Reappraising of Cosmography: the Interface Between Astronomical and Geographic Studies. (Breton Title: Releitura do Conceito de Cosmografia: a Interface Entre os Estudos Astronômicos e Geográficos.) Una Relectura del Concepto de Cosmografía: la Interfase Entre los Estudios Astronómicos y Geográficos

    NASA Astrophysics Data System (ADS)

    Azevedo Sobreira, Paulo Henrique

    2012-12-01

    The concept of "Cosmography" is in disuse since the 80s of the last century, but the astronomical themes previously discussed in the school subjects of Geography and Cosmography remain in current textbooks. The use of term "Cosmography" was rescued in this research, and the study of its re-signification prompted the appearance of the term Geographic Cosmography. The Geographic Cosmography is a field of studies of the Geography, whose set of knowledge and skills is predominantly scholar. It studies the interface between terrestrial and celestial knowledge, and assigns a geographic significance to them. It examines human and natural relationships with Sidereal Space and its consequences for society and nature. O conceito de "Cosmografia" está em desuso desde os anos 80 do século XX, mas os temas astronômicos anteriormente abordados nas disciplinas escolares de Cosmografia e de Geografia permanecem nos atuais livros didáticos. O uso do termo "Cosmografia" foi resgatado nesta pesquisa e o estudo de sua ressignificação proporcionou o surgimento do termo Cosmografia Geográfica. A Cosmografia Geográfica é um campo de estudos da Geografia, cujo conjunto de conhecimentos e habilidades é predominantemente escolar. Estuda a interface entre os conhecimentos terrestres e os celestes e lhes atribui significância geográfica. Analisa as relações humanas e naturais com o Espaço Sideral e suas consequências para a sociedade e a natureza.

    Aunque el concepto de "Cosmografía" no se usa desde la década de los '80 del siglo pasado, los temas astronómicos que se enseñaban anteriormente en las asignaturas escolares de Cosmografía y de Geografía permanecen en los actuales libros didácticos. El uso del término "Cosmografía" fue rescatado en esta investigación y el estudio de su resignificación proporcionó el surgimiento del término Cosmografía Geográfica. La Cosmografía Geográfica es un campo de estudio de la Geografía, donde

  12. Values, animal symbolism, and human-animal relationships associated to two threatened felids in Mapuche and Chilean local narratives

    PubMed Central

    2013-01-01

    Background The Chilean temperate rainforest has been subjected to dramatic fragmentation for agriculture and forestry exploitation. Carnivore species are particularly affected by fragmentation and the resulting resource use conflicts with humans. This study aimed at understanding values and human-animal relationships with negatively perceived threatened carnivores through the disclosure of local stories and Mapuche traditional folktales. Methods Our mixed approach comprised the qualitative analysis of 112 stories on the kodkod cat (Leopardus guigna) and the puma (Puma concolor) collected by students (9-14 years) from 28 schools in the Araucania region within their family contexts, 10 qualitative in-depth interviews with indigenous Mapuche people, 35 traditional Mapuche legends, and the significance of naming found in ethnographic collections. Results We revealed a quasi-extinction of traditional tales in the current knowledge pool about pumas and kodkods, local anecdotes, however, were present in significant numbers. Values associated to both felids were manifold, ranging from negativistic to positive values. While pumas played an important role in people’s spirituality, negative mythological connotations persisted in kodkod stories. Four prominent relationships were derived: (1) Both felids represent threats to livestock, pumas even to life, (2) both felids are symbols for upcoming negative events, (3) pumas are spiritual creatures, and (4) kodkods are threatened by humans. Recommendations are provided for stimulating new ways of perceiving unpopular and threatened carnivores among those who live in vicinity to them. PMID:23764186

  13. Poverty determinants of acute respiratory infections among Mapuche indigenous peoples in Chile's Ninth Region of Araucania, using GIS and spatial statistics to identify health disparities

    PubMed Central

    Rojas, Flavio

    2007-01-01

    Background This research concerns Araucanía, often called the Ninth Region, the poorest region of Chile where inequalities are most extreme. Araucanía hasn't enjoyed the economic success Chile achieved when the country returned to democracy in 1990. The Ninth Region also has the largest ethnic Mapuche population, located in rural areas and attached to small agricultural properties. Written and oral histories of diseases have been the most frequently used methods to explore the links between an ancestral population's perception of health conditions and their deprived environments. With census data and hospital records, it is now possible to incorporate statistical data about the links between poverty and disease among ethnic communities and compare results with non-Mapuche population. Data sources Hospital discharge records from Health Services North N = 24,126 patients, year 2003, and 7 hospitals), Health Services South (N = 81,780 patients and 25 hospitals); CAS-2/Family records (N = 527,539 individuals, 439 neighborhoods, 32 Comunas). Methods Given the over-dispersion of data and the clustered nature of observations, we used the global Moran's I and General G Gettis-Ord procedures to test spatial dependence. These tests confirmed the clusters of disease and the need to use spatial regression within a General Linear Mixed Model perspective. Results Health outcomes indicate significantly higher morbidity rates for the Mapuche compared to non-Mapuche in both age groups < 5 and 15–44, respectively; for the groups 70–79 and 80 + years of age, this trend is reversed. Mortality rates, however, are higher among Mapuches than non-Mapuches for the entire Ninth Region and for all age groups. Mortality caused by respiratory infections is higher among Mapuches than non-Mapuches in all age-groups. A major finding is the link between poverty and respiratory infections. Conclusion Poverty is significantly associated with respiratory infections in the population of Chile

  14. The influence of Christian conversion in Mapuche traditional medicine in Temuco, Chile: toward a cultural syncretism or a form of ideological assimilation?

    PubMed

    Torri, Maria Costanza

    2013-12-01

    The Mapuche communities living in the urban areas of Chile have undergone radical cultural changes due to Christian conversion. This article analyzes the influence of these changes on the Mapuche ideas and practices of the traditional healers (machi) and patients in Temuco (IX Region), Chile, and the changes and adaptations in the perceptions of healing practices and rituals by the patients. The paper shows how, despite some evident challenges, the encounter with the religion of Christianity can create a process of cultural and spiritual syncretism and push traditional medicine toward an increased specialization in the therapeutic practices. PMID:22203378

  15. HLA non-class II genes may confer type I diabetes susceptibility in a Mapuche (Amerindian) affected family.

    PubMed

    Pérez-Bravo, Francisco; Martinez-Laso, Jorge; Martin-Villa, Jose M; Moscoso, Juan; Moreno, Almudena; Serrano-Vela, Juan I; Zamora, Jorge; Asenjo, Silvia; Gleisner, Andrea; Arnaiz-Villena, Antonio

    2006-01-01

    A rare case of type I diabetes is studied in an Amerindian (Mapuche) family from Chile, analyzing glutamic acid decarboxylase, islet-cell autoantibodies and human leukocyte antigen (HLA) genes. The affected sib is the only one that has one specific HLA haplotype combination that differs from the other sibs only in the HLA class I genes. It is concluded that HLA diabetes susceptibility factors may be placed outside the class II region or even that susceptibility factors do not exist in the HLA region in this Amerindian family. PMID:16473308

  16. [Iron supplementation in Chilean Mapuche infants of the Cautin Province, Chile].

    PubMed

    Franco, E; Hertrampf, E; Hazbún, J; Segú, S; Illanes, J C; Palacios, L; Figueroa, G; Orellana, J

    1996-06-01

    A 1.8 ml iron supplementation of ferrous sulfate is administered for 90 days to 76 Mapuche infants, 12 months of age, male and female, from the rural area of the Cautin province of Chile. The iron nutrition is evaluated before and after the supplementation, through: hemoglobin, haematocrit, transferrin saturation and seric ferritin. Stools test are taken at the infant's home, to confirm the supplement intake and to measure the iron excreted. To study the contained of dietary Fe a Recordatory 24 hour Inquest (RI) is applied moreover a Proximal Chemical Analysis (PCHA) to meal test proceeding from the infant's homes. At 12 months before starting the supplementation, the anemia prevalence was of 28.3%, but it disappear as a result of the intervention. Also 65.3% of the infants showed and increase of 1 g or more on their hemoglobin, which indicates that they were anemic at the beginning of the iron supplementation. By means of this therapeutic test it was find 31% more of anemic infants, indicating more sensibility of this method. The high levels of anemia prevalence are due to the low iron intake, characteristic of the non lactious foods, which according results of the RI reaches an average of 2.8 +/- 1.2 mg of Fe/day, versus 4.8 +/- 4.0 mg of Fe/day according to PCHA. The observed difference between both test showed that there is a process of food environmental contamination, by the use of iron utensils and great soil contact. The high environmental contamination could also be proved by the high iron excretion stools (140 mg of Fe/100 g of stools). This method used to measure the Fe excretion of the supplement, would not be valid in rural population groups with similar characteristics to those of the studied group, because it does not discriminate between the intake and the extremely high environmental contamination. To prevent anemia due to iron absence in infants, it is absolutely necessary to have some iron fortified food starting at 6 months of age, as a

  17. HLA-E polymorphism in Amerindians from Mexico (Mazatecans), Colombia (Wayu) and Chile (Mapuches): evolution of MHC-E gene.

    PubMed

    Arnaiz-Villena, A; Vargas-Alarcon, G; Serrano-Vela, J I; Reguera, R; Martinez-Laso, J; Silvera-Redondo, C; Granados, J; Moscoso, J

    2007-04-01

    Human leukocyte antigen (HLA)-E is a nonclassical class I (Ib) gene with a restricted polymorphism. Only eight DNA alleles and three proteins of this gene have been described and their frequencies analyzed in Caucasian, Oriental, Asian Indian, and Negroid populations. In the present study, HLA-E polymorphism has been analyzed in six Amerindian and Mestizo populations from North and South America and compared with previously described populations. HLA-E*0101 is the most frequent allele found in all populations except in Afrocolombian and Wayu Amerindians, in which blood group analyses show a high admixture with Caucasian and African populations. Mazatecan and Mapuche (two Amerindian groups from North and South America, respectively) presented similar HLA-E frequencies, whereas Wayu Indians are more similar to the Afrocolombian population. The Mexican and Colombian Mestizo show similar allele frequencies to Amerindians with high frequencies of HLA-E*0101 and HLA-E*010302 alleles. Also, frequencies in Negroids and Asian Indians present a similar distribution of HLA-E alleles. These data are in agreement with worldwide restricted polymorphism of HLA-E because no new allele was detected in the six populations studied. The allelic frequencies show differences among Caucasian, Oriental, Mestizo and Indian populations. Ape major histocompatibility complex-E allelism is also very restricted: common chimpanzee (one allele); bonobo (two alleles); gorilla (two alleles); orangutan (one allele); rhesus monkey (eight alleles); cynomolgus monkey (two alleles); and green monkey (two alleles). PMID:17445187

  18. 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. PMID:25157036

  19. Os Trigonum Syndrome

    MedlinePlus

    ... ACFAS | Información en Español Advanced Search Home » Foot & Ankle Conditions » Os Trigonum Syndrome Text Size Print Bookmark ... extra (accessory) bone that sometimes develops behind the ankle bone (talus). It is connected to the talus ...

  20. Medicinal plants in the cultural landscape of a Mapuche-Tehuelche community in arid Argentine Patagonia: an eco-sensorial approach

    PubMed Central

    2014-01-01

    Background The taste and smell of medicinal plants and their relation to the cultural landscape of a Mapuche-Tehuelche community in the Patagonian steppe was investigated. We assume that the landscapes as a source of therapeutic resources is perceived, classified and named according to different symbolic, ecological and utilitarian criteria which are influenced by chemosensorial appearance of medicinal plants which are valued by inhabitants. Methods Information relating to the cultural landscape experienced by 18 inhabitants, all representing 85% of the families, in terms of medicinal plants, knowledge of species and their organoleptic perception was obtained through participant observation, interviews and free listing. The data were examined using cualitative and quantitative approach, including discourse analysis and non-parametric statistics. Results Informants use 121 medicinal species, obtained from both wild and non-wild environments, most of which (66%) present aroma and/or taste. It was found that the plants with highest use consensus used for digestive, respiratory, cardio-vascular, analgesic-anti-inflammatory, obstetric-gynaecological and genito-unrinary complaints, have the highest frequencies of cites reporting flavor; and those with the highest frequencies relating to digestive, analgesic-anti-inflammatory and cultural syndromes present the highest frequencies of aroma. Flavor and/or aroma are interpreted as strong or soft, and the strongest are associated with treatment of supernatural ailments. Also, taste is a distinctive trait for the most of the species collected in all natural units of the landscape, while aroma is more closely associated with species growing at higher altitudes. The local pharmacopeia is also enriched with plants that come from more distant phytogeographical environments, such as the Andean forest and the Patagonian Monte, which are obtained through barter with neighboring populations. Herbal products are also obtained in

  1. "Entre libre" dans la classe ("Entre Libre" in the Classroom).

    ERIC Educational Resources Information Center

    Compte, Carmen

    1987-01-01

    In an interview, two teachers describe and discuss their different classroom use of the same set of instructional materials for "Entre Libre" and compare the results. Activities include role playing, music, and reporting. (MSE)

  2. 186Os- 187Os systematics of Hawaiian picrites revisited: New insights into Os isotopic variations in ocean island basalts

    NASA Astrophysics Data System (ADS)

    Ireland, T. J.; Walker, R. J.; Brandon, A. D.

    2011-08-01

    Eighteen picrites (MgO > 13 wt.%) and three related basalts from six Hawaiian volcanoes were analyzed for 187Os/ 188Os and 186Os/ 188Os. Variations in these ratios reflect long-term Re/Os and Pt/Os differences in the mantle source regions of these volcanoes. 187Os/ 188Os ratios vary from ˜0.129 to 0.136, consistent with the range defined by previous studies of Hawaiian picrites and basalts. Samples with lower 187Os/ 188Os are mainly from Kea trend volcanoes (Mauna Kea and Kilauea), and the more radiogenic samples are mainly from Loa trend volcanoes (Mauna Loa, Hualalai, Koolau and Loihi). As previously suggested, differences in 187Os/ 188Os between volcanic centers are most consistent with the presence of variable proportions of recycled materials and/or pyroxenitic components in the Hawaiian source. 186Os/ 188Os ratios vary from 0.1198332 ± 26 to 0.1198480 ± 20, with some samples having ratios that are significantly higher than current estimates for the ambient upper mantle. Although the range of 186Os/ 188Os for the Hawaiian suite is consistent with that reported by previous studies, the new data reveal significant heterogeneities among picrites from individual volcanoes. The linear correlation between 187Os/ 188Os and 186Os/ 188Os reported by a previous study is no longer apparent with the larger dataset. The postulated recycled materials and pyroxenites responsible for the dominant variations in 187Os/ 188Os are likely not responsible for the variations in 186Os/ 188Os. Such materials are typically characterized by both insufficiently high Os concentrations and Pt/Os to account for the 186Os/ 188Os heterogeneities. The lack of correspondence between 186Os/ 188Os variations and the Kea and Loa trends supports this conclusion. The primary cause of 186Os/ 188Os variations are evaluated within the framework of two mixing scenarios: (1) metasomatic transport of Pt and/or 186Os-rich Os into some portions of the Hawaiian source, and (2) interaction between an

  3. [In Process Citation].

    PubMed

    Álvarez, Cristian; Ramírez-Campillo, Rodrigo; Vallejos-Rojas, Andrea; Jaramillo-Gallardo, Javiera; Salas Bravo, Carlos; Cano-Montoya, Johnattan; Celis-Morales, Carlos

    2016-01-01

     Introducción: obesidad e inactividad física son importantes factores de riesgo para el desarrollo de hipertensión en adultos. No obstante, hay poca evidencia sobre el efecto de estos factores de riesgo en el desarrollo de hipertensión en población infantil. Objetivo: investigar la asociación del estado nutricional, niveles de actividad física y etnicidad con niveles de hipertensión en escolares entre 6 y 13 años de edad. Métodos: un total de 418 escolares de ascendencia étnica europea (n = 311) y mapuche (n = 107) fueron participantes de este estudio transversal. Se midió el peso, talla, índice de masa corporal (IMC) y presión arterial, utilizando protocolos estandarizados. Resultados: no se encontraron diferencias significativas en IMC, estado nutricional y presión arterial entre niños con ascendencia europea y mapuche. No obstante, la prevalencia de prehipertensión (21,3% vs. 11,1%) e hipertensión (28,9% vs. 18,6%) fue significativamente mayor en escolares mapuches en comparación con europeos, respectivamente. Escolares con ascendencia mapuche tienen un mayor riesgo de desarrollar prehipertensión o hipertensión que escolares con ascendencia europea (OR: 1,92 [1,19 a 3,06], p < 0,01). La prevalencia de hipertensión aumenta significativamente en ambos grupos étnicos con el incremento de IMC y bajos niveles de actividad física. Conclusiones: el riesgo de desarrollar prehipertensión o hipertensión es mayor en población infantil ascendiente de mapuches que ascendiente de europeos y este riesgo se ve acentuado con el incremento de obesidad y bajos niveles de actividad física. PMID:27238776

  4. [sup 187]Os-[sup 186]Os and [sup 187]Os-[sup 188]Os method of dating: An introduction

    SciTech Connect

    Yin, Q.Z.; Jagoutz, E.; Waenke, H. ); Verkhovskiy, A.B. )

    1993-08-01

    A Re-containing sample is irradiated with thermal neutrons in a nuclear reactor. The following reactions occur with high cross sections: [sup 185]Re(n, [gamma])[sup 186]Re and [sup 187]Re(n, [gamma])[sup 188]Re. Both [sup 186]Re (half-life 90.6 h) and [sup 188]Re (16.7 h) [beta]-decay to the stable isotopes [sup 186]Os and [sup 188]Os. Thus [sup 186]Os and [sup 188]Os are enriched in proportion to the neutron fluence and R/Os ratio of the sample being irradiated. Analyzing merely the isotopic composition of the sample, the authors get two ages that should be consistent. In one irradiated molybdenite sample from Kingsgate molybdenum mine in New South Wales, Australia, the measured [sup 186]Os/[sup 192]Os and [sup 188]Os/[sup 192]Os are 0.3284 and 0.6299, whereas in an unirradiated sample they are assumed to be 0.0390 and 0.3248. These ratios are measurable with negative thermal ionization mass spectrometry (N-TIMS) to a precision of 1[per thousand]. The derived ages for this sample are t[sub 186] = 220.5 [+-] 8.6 Ma and t[sub 188] = 214.9 [+-] 8.9 Ma, respectively (or [+-] 1.4 Ma and [+-] 1.7 Ma, respectively, when excluding the uncertainty of [sup 187]Re half-life). These values are in close agreement with the 221--238 Ma K-Ar ages of the leucogranites emplacement that causes the Mo mineralization at Kingsgate. The major limiting factor on the precision of this age determination is the uncertainty in the half-life of [sup 187]Re. The errors associated with the irradiation parameters are greatly reduced by choosing an appropriate neutron flux monitor. The advantage of this method is that the Re/Os ratio is determined on the same sample and that only one measurement of the isotope composition of osmium is required, thus overcoming some of the experimental difficulties of the conventional Re-Os analysis. The problem of sample inhomogeneity and the need to measure the absolute concentrations of rhenium and osmium are thus eliminated. 30 refs., 3 figs., 1 tab.

  5. Estimation of continental 187Os/186Os values by using 187Os/186Os and 143Nd/144Nd ratios in marine manganese nodules

    PubMed Central

    Turekian, Karl K.; Luck, Jean-Marc

    1984-01-01

    The relationship between 187Os/186Os and 143Nd/144Nd in different manganese nodule fields is used to determine the 187Os/186Os ratio of the continental terrains bounding the major ocean basins. The Atlantic Ocean drainages yield 187Os/186Os of about 11; the Pacific Ocean, between 25 and 36; and the western Indian Ocean, 20. By assuming a two-component continental crust composed of “ultramafic rocks” (high Os concentration, low 187Os/186Os) and “granite” with only radiogenic 187Os produced in accessory Re-bearing molybdenite, the ultramafic contribution to weathering is about 0.2%. Some or most of this may come from the alteration of oceanic ultramafics. PMID:16578780

  6. Estudo comparativo entre estrelas centrais de nebulosas planetárias deficientes em hidrogênio

    NASA Astrophysics Data System (ADS)

    Marcolino, W. L. F.; de Araújo, F. X.

    2003-08-01

    Apresentamos neste trabalho o resultado de um estudo das principais características espectrais das estrelas centrais de nebulosas planetárias (ECNP) deficientes em hidrogênio. A origem e a evolução dessas estrelas ainda constitui um problema em aberto na evolução estelar. Geralmente esses objetos são divididos em [WCE], [WCL] e [WELS]. Os tipos [WCE] e [WCL] apresentam um espectro típico de uma estrela Wolf-Rayet carbonada de população I e as [WELS] apresentam linhas fracas de carbono e oxigênio em emissão. Existem evidências que apontam a seguinte sequência evolutiva : [WCL] = > [WCE] = > [WELS] = > PG 1159 (pré anã-branca). No entanto, tal cenário apresenta falhas como por exemplo a falta de ECNP entre os tipos [WCL] e [WCE]. Baseados em uma amostra de 24 objetos obtida no telescópio de 1.52m em La Silla, Chile (acordo ESO/ON), ao longo do ano 2000, apresentamos os resultados da comparação das larguras equivalentes de diversas linhas relevantes entre os tipos [WCL], [WCE] e [WELS]. Verificamos que nossos dados estão de acordo com a sequência evolutiva. Baseado nas linhas de C IV, conseguimos dividir pela primeira vez as [WELS] em dois grupos principais. Além disso, os dados reforçam a afirmação de que as [WCE] são as estrelas que possuem a maior temperatura entre as ECNP deficientes em hidrogênio. Discutimos ainda, a escassez de dados disponíveis na literatura e a necessidade da obtenção de parametros físicos para estes objetos.

  7. 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

  8. Miocene seawater 187Os/ 188Os ratios inferred from metalliferous carbonates

    NASA Astrophysics Data System (ADS)

    Reusch, Douglas N.; Ravizza, Greg; Maasch, Kirk A.; Wright, James D.

    1998-07-01

    Seawater 187Os/ 188Os ratios for the Middle Miocene were reconstructed by measuring the 187Os/ 188Os ratios of metalliferous carbonates from the Pacific (DSDP 598) and Atlantic (DSDP 521) oceans. Atlantic and Pacific 187Os/ 188Os measurements are nearly indistinguishable and are consistent with previously published Os isotope records from Pacific cores. The Atlantic data reported here provide the first direct evidence that the long-term sedimentary 187Os/ 188Os record reflects whole-ocean changes in the Os isotopic composition of seawater. The Pacific and the Atlantic Os measurements confirm a long-term 0.01/Myr increase in marine 187Os/ 188Os ratios that began no later than 16 Ma. The beginning of the Os isotopic increase coincided with a decrease in the rate of increase of marine 87Sr/ 86Sr ratios at 16 Ma. A large increase of 1‰ in benthic foraminiferal δ18O values, interpreted to reflect global cooling and ice sheet growth, began approximately 1 million years later at 14.8 Ma, and the long-term shift toward lower bulk carbonate δ13C values began more than 2 Myr later around 13.6 Ma. The post-16 Ma increase in marine 187Os/ 188Os ratios was most likely forced by weathering of radiogenic materials, either old sediments or sialic crust with a sedimentary protolith. We consider two possible Miocene-specific geologic events that can account for both this increase in marine 187Os/ 188Os ratios and also nearly constant 87Sr/ 86Sr ratios: (1) the first glacial erosion of sediment-covered cratons in the Northern Hemisphere; (2) the exhumation of the Australian passive margin-New Guinea arc system. The latter event offers a mechanism, via enhanced availability of soluble Ca and Mg silicates in the arc terrane, for the maintenance of assumed low CO 2 levels after 15 Ma. The temporal resolution (three samples/Myr) of the 187Os/ 188Os record from Site 598, for which a stable isotope stratigraphy was also constructed, is significantly higher than that of previously

  9. 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.

  10. 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. PMID:26337938

  11. 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.

  12. Problems with Re-Os isochron determinations

    NASA Astrophysics Data System (ADS)

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

    1994-07-01

    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.

  13. 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.

  14. 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

  15. Involvement of the OsMKK4-OsMPK1 Cascade and its Downstream Transcription Factor OsWRKY53 in the Wounding Response in Rice

    PubMed Central

    Yoo, Seung Jin; Kim, Su-Hyun; Kim, Min-Jeong; Ryu, Choong-Min; Kim, Young Cheol; Cho, Baik Ho; Yang, Kwang-Yeol

    2014-01-01

    Plant has possessed diverse stress signals from outside and maintained its fitness. Out of such plant responses, it is well known that mitogen-activated protein kinase (MAPK) cascade plays important role in wounding and pathogen attack in most dicot plants. However, little is understood about its role in wounding response for the economically important monocot rice plant. In this study, therefore, the involvement of MAPK was investigated to understand the wounding signaling pathway in rice. The OsMPK1 was rapidly activated by wounding within 10 min, and OsMPK1 was also activated by challenge of rice blast fungus. Further analysis revealed that OsMKK4, the upstream kinase of OsMPK1, phosphorylated OsMPK1 by wounding in vivo. Furthermore, OsMPK1 directly interacted with a rice defense-related transcription factor OsWRKY53. To understand a functional link between MAPK and its target transcription factor, we showed that OsMPK1 activated by the constitutively active mutant OsMKK4DD phosphorylated OsWRKY53 in vitro. Taken together, components involving in the wounding signaling pathway, OsMKK4-OsMPK1-OsWRKY53, can be important players in regulating crosstalk between abiotic stress and biotic stress. PMID:25288999

  16. Involvement of the OsMKK4-OsMPK1 Cascade and its Downstream Transcription Factor OsWRKY53 in the Wounding Response in Rice.

    PubMed

    Yoo, Seung Jin; Kim, Su-Hyun; Kim, Min-Jeong; Ryu, Choong-Min; Kim, Young Cheol; Cho, Baik Ho; Yang, Kwang-Yeol

    2014-06-01

    Plant has possessed diverse stress signals from outside and maintained its fitness. Out of such plant responses, it is well known that mitogen-activated protein kinase (MAPK) cascade plays important role in wounding and pathogen attack in most dicot plants. However, little is understood about its role in wounding response for the economically important monocot rice plant. In this study, therefore, the involvement of MAPK was investigated to understand the wounding signaling pathway in rice. The OsMPK1 was rapidly activated by wounding within 10 min, and OsMPK1 was also activated by challenge of rice blast fungus. Further analysis revealed that OsMKK4, the upstream kinase of OsMPK1, phosphorylated OsMPK1 by wounding in vivo. Furthermore, OsMPK1 directly interacted with a rice defense-related transcription factor OsWRKY53. To understand a functional link between MAPK and its target transcription factor, we showed that OsMPK1 activated by the constitutively active mutant OsMKK4(DD) phosphorylated OsWRKY53 in vitro. Taken together, components involving in the wounding signaling pathway, OsMKK4-OsMPK1-OsWRKY53, can be important players in regulating crosstalk between abiotic stress and biotic stress. PMID:25288999

  17. 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.

  18. [Advances in baculovirus per os infection and per os infectivity factor--A review].

    PubMed

    Li, Hui; Guo, Caiping; Zhu, Shimao

    2015-04-01

    Baculoviruses are a family of arthropod-specific viruses that mainly affect insects of the orders Lepidoptera, Hymenoptera, and Diptera. In nature, baculoviruses establish infection in their hosts orally and a battery of proteins designated as per os infectivity factors play pivotal roles in baculovirus per os infection. This review summarizes the basic characteristics of baculovirus and discusses the main events that baculovirus establishes per os infection, including the evolutionary advantages for baculovirus to initiate infection through the oral route, the binding and fusion of baculovirus virions with insect midgut microvilli and the functional roles of baculovirus per os infectivity factors. These achievements and advances should promise to shed light on the understanding and utilization of baculovirus for bio-control and exogenous gene expression in the future. PMID:26211313

  19. Low-lying excited states in the neutron-deficient isotopes 163Os and 165Os

    NASA Astrophysics Data System (ADS)

    Drummond, M. C.; Joss, D. T.; Page, R. D.; Simpson, J.; O'Donnell, D.; Andgren, K.; Bianco, L.; Cederwall, B.; Darby, I. G.; Eeckhaudt, S.; Gomez-Hornillos, M. B.; Grahn, T.; Greenlees, P. T.; Hadinia, B.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leppänen, A.-P.; Leino, M.; Nyman, M.; Pakarinen, J.; Rahkila, P.; Sandzelius, M.; Sapple, P. J.; Sarén, J.; Saygi, B.; Scholey, C.; Sorri, J.; Thomson, J.; Uusitalo, J.; Venhart, M.

    2013-05-01

    Excited states in the neutron-deficient isotopes 163Os and 165Os were identified using the JUROGAM and GREAT spectrometers in conjunction with the RITU gas-filled separator. The 163Os and 165Os nuclei were populated via the 106Cd(60Ni,3n) and 92Mo(78Kr,2p3n) reactions at bombarding energies of 270 MeV and 357 MeV, respectively. Gamma-ray emissions from these nuclei have been established unambiguously using the recoil-decay tagging technique and a coincidence analysis has allowed level schemes to be established. These results suggest that the yrast states are based upon negative-parity configurations originating from the νf7/2 and νh9/2 orbitals.

  20. 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.

  1. Re-Os systematics of St. Paul's Rocks, equatorial Atlantic.

    NASA Astrophysics Data System (ADS)

    Blusztajn, J.; Hart, S. R.

    2006-12-01

    St. Paul's Rocks, small islets in the middle of the equatorial Atlantic (0°56'N, 29°22'W) just north of the St. Paul's Fracture zone, represent oceanic peridotites that are unique compared to abyssal peridotites. The main difference is the occurrence of modally metasomatized peridotites containing hornblende and pargasite. These mantle peridotites from St. Paul's Rocks show large Os isotopic heterogeneity, with present day 187Os/188Os ratios ranging from 0.1179 to 0.1273. In contrast, two hornblendite samples have very radiogenic Os isotopic compositions of 0.221 and 0.284. The Os concentrations vary from 0.003 ppb (hornblendite) to 5.8 ppb (spinel peridotite). Pargasite peridotites contain on average about 1.6 ppb Os. Even modally metasomatized samples with hornblende and pargasite have subchondritic Os isotopic ratios, indicating that enrichment processes did not disturb the Os isotopic system. The only indication of pervasive enrichment is a very high Re content in two of the amphibole peridotites (0.7 and 2.2 ppb). The unradiogenic Os isotopic ratios in the peridotites record ancient melting events with model ages of about 1.5 Ga. Three alkali basalts dredged on the flank of St. Paul's Rocks (1966 Atlantis II-20 cruise) have relatively high Os contents (62 to 167 ppt) and are quite radiogenic, with 187Os/188Os ranging from 0.167 to 0.239. Data from this study indicates that mixing of the different lithologies observed on St. Paul's Rocks cannot produce 187Os/188Os as high as that observed in the dredged basalts. On the other hand, the similar 187Os/188Os in the hornblendites and alkali basalts show that interaction between basalts and mantle peridotites took place. The very low Os isotopic ratios in St. Paul's Rocks, in conjunction with other Os studies from the equatorial Atlantic, indicate dispersed heterogeneities of old subcontinental lithospheric material in the oceanic mantle.

  2. Seroprevalence of Salmonella and Mycoplasma infection in backyard chickens in the state of Entre Rios in Argentina.

    PubMed

    Xavier, J; Pascal, D; Crespo, E; Schell, H L; Trinidad, J A; Bueno, D J

    2011-04-01

    The present work was conducted to study the seroprevalence of Salmonella, Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS) infection in backyard chickens located in Entreos, Argentina, over 3 periods of time. A total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of Entreos from January to May 2003 (first period), December 2004 to April 2005 (second period), and October 2006 to May 2007 (third period). The prevalence of family farms testing seropositive for Salmonella averaged 23.9, 15.9, and 28.6% during the first, second, and third period, respectively. The highest prevalence of Salmonella-seropositive farms recorded (66.7%) was on farms from Concordia county, and the lowest prevalence (0%) was on farms from La Paz county. In contrast, the prevalence of family farms seropositive for MG averaged 32.8, 55.1, and 76.2% during the first, second, and third periods, respectively. The highest prevalence of MG-seropositive farms (100%) was found in the counties of Victoria and Tala, and the lowest prevalence (8.7%) was found on farms on Colón county. The prevalence of family farms seropositive for MS averaged 68.6 and 100% during the first and second periods, respectively. The highest prevalence of MS-seropositive farms (100%) was on farms in 85% of the counties tested, and the lowest prevalence (21.7%) was on farms from Colón county. Salmonella, MG, and MS infection are present at high levels in backyard chicken farms, and this presents a high risk to commercial poultry production in Entreos, the state with the highest chicken population and density in Argentina. PMID:21406358

  3. Investigation into the mechanism of action of the antimicrobial peptides Os and Os-C derived from a tick defensin.

    PubMed

    Taute, Helena; Bester, Megan J; Neitz, Albert W H; Gaspar, Anabella R M

    2015-09-01

    Os and Os-C are two novel antimicrobial peptides, derived from a tick defensin, which have been shown to have a larger range of antimicrobial activity than the parent peptide, OsDef2. The aim of this study was to determine whether the peptides Os and Os-C are mainly membrane acting, or if these peptides have possible additional intracellular targets in Escherichia coli and Bacillus subtilis. Transmission electron microscopy revealed that both peptides adversely affected intracellular structure of both bacteria causing different degrees of granulation of the intracellular contents. At the minimum bactericidal concentrations, permeabilization as determined with the SYTOX green assay seemed not to be the principle mode of killing when compared to melittin. However, fluorescent triple staining indicated that the peptides caused permeabilization of stationary phase bacteria and TEM indicated membrane effects. Studies using fluorescently labeled peptides revealed that the membrane penetrating activity of Os and Os-C was similar to buforin II. Os-C was found to associate with the septa of B. subtilis. Plasmid binding studies showed that Os and Os-C binds E. coli plasmid DNA at a similar charge ratio as melittin. These studies suggest membrane activity for Os and Os-C with possible intracellular targets such as DNA. The differences in permeabilization at lower concentrations and binding to DNA between Os and Os-C, suggest that the two peptides have dissimilar modes of action. PMID:26215047

  4. 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

    2014-01-01

    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

  5. 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

  6. 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.

  7. Multilobular osteochondrosarcoma of the os penis in a dog

    PubMed Central

    Webb, Jinelle A.; Liptak, Julius M.; Hewitt, Saundra A.; Vince, Andrew R.

    2009-01-01

    Multilobular osteochondrosarcoma (MLO) of the os penis was diagnosed in a dysuric dog. Recurrence was confirmed or suspected twice over a 22-month period. This is the first reported case of MLO occurring in the os penis, and the 5th reported case of neoplasia of the os penis in the dog. PMID:19337619

  8. 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.

  9. 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.

  10. Coulomb excitation of {sup 189}Os

    SciTech Connect

    Seale, W.A.; Botelho, S.; Ribas, R.V.

    1993-10-01

    The transitional nucleus {sup 189}Os has been studied by Coulomb excitation. Measurements with a Ge(HP) detector were made at 0{degrees}, 55{degrees}, 90{degrees} with beams of {sup 28}Si at 80 and 88 Me {sup 35}Cl at 80 MeV and {sup 16}O at 58 MeV. A total of gamma-ray transitions leading to 23 levels we used in the least-squares code GOSIA to determined reduced matrix elements. A theoretic understanding of this nucleus has been attempt from the point of view of current nuclear mode as they apply to systematics of the 1/2 {sup -}[510] 3/2 -[512], 1/2 [503] levels in this ma region.

  11. Functional characterization of rice OsDof12.

    PubMed

    Li, Dejun; Yang, Chunhua; Li, Xiaobing; Gan, Qiang; Zhao, Xianfeng; Zhu, Lihuang

    2009-05-01

    DNA-binding with one finger (Dof) proteins are a large family of transcription factors involved in a variety of biological processes in plants. In rice, 30 different Dof genes have been identified through genome analysis. Here we report the functional characteristics of a rice Dof gene, OsDof12, which encodes a predicted Dof protein. The nuclear localization of OsDof12 was investigated by the transient expression assays of the OsDof12-GFP fusion protein in onion epidermal cells. Trans-activation assays in a yeast one-hybrid system indicated that OsDof12 had transcriptional activity. RNA expression analyses showed that the expression of OsDof12 was not tissue-specific in general and fluctuated at different development stages in rice. In addition, OsDof12 was strongly inhibited by dark treatments. The transgenic lines overexpressing OsDof12 showed early flowering under long-day (LD) conditions, whereas OsDof12 overexpression had no effect on flowering time under short-day (SD) conditions. In transgenic lines overexpressing OsDof12, the transcription levels of Hd3a and OsMADS14 were up-regulated under LD conditions but not SD conditions, whereas the expression of Hd1, OsMADS51, Ehd1 and OsGI did not change under LD and SD conditions. These results suggested that OsDof12 might regulate flowering by controlling the expression of Hd3a and OsMADS14. PMID:19198875

  12. Os2 -Os4 Switch Controls DNA Knotting and Anticancer Activity.

    PubMed

    Fu, Ying; Romero, María J; Salassa, Luca; Cheng, Xi; Habtemariam, Abraha; Clarkson, Guy J; Prokes, Ivan; Rodger, Alison; Costantini, Giovanni; Sadler, Peter J

    2016-07-25

    Dinuclear trihydroxido-bridged osmium-arene complexes are inert and biologically inactive, but we show here that linking dihydroxido-bridged Os(II) -arene fragments by a bridging di-imine to form a metallacycle framework results in strong antiproliferative activity towards cancer cells and distinctive knotting of DNA. The shortened spacer length reduces biological activity and stability in solution towards decomposition to biologically inactive dimers. Significant differences in behavior toward plasmid DNA condensation are correlated with biological activity. PMID:27240103

  13. 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.

  14. Thermal stability of hexagonal OsB2

    SciTech Connect

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

    2014-01-01

    The synthesis of novel hexagonal ReB2-type OsB2 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 10B and 11B isotopes with a fine particle size, while another B powder was a purely crystalline (rhombohedral) material consisting of enriched 11B 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 OsB2 phase was the main product of synthesis with a small quantity of Os2B3 phase present after synthesis as an intermediate product. In the second case, where coarse crystalline 11B powder was used as a raw material, only Os2B3 boride was synthesized mechanochemically. The thermal stability of hexagonal OsB2 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 2OsB2+3O2 2Os+2B2O3 took place due to presence of O2/water vapor molecules in the heating chamber, resulting in the oxidation of B atoms and formation of B2O3 and precipitation of Os metal out of the OsB2 lattice. As a result of such phase changes during heating, the lattice parameters of hexagonal OsB2 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 OsB2 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 O2, the hexagonal OsB2 ceramic demonstrated good phase stability upon cooling in vacuo with linear shrinkage of the lattice parameters and no phase changes detected during cooling.

  15. Os2–Os4 Switch Controls DNA Knotting and Anticancer Activity

    PubMed Central

    Fu, Ying; Romero, María J.; Salassa, Luca; Cheng, Xi; Habtemariam, Abraha; Clarkson, Guy J.; Prokes, Ivan; Rodger, Alison; Costantini, Giovanni

    2016-01-01

    Abstract Dinuclear trihydroxido‐bridged osmium–arene complexes are inert and biologically inactive, but we show here that linking dihydroxido‐bridged OsII–arene fragments by a bridging di‐imine to form a metallacycle framework results in strong antiproliferative activity towards cancer cells and distinctive knotting of DNA. The shortened spacer length reduces biological activity and stability in solution towards decomposition to biologically inactive dimers. Significant differences in behavior toward plasmid DNA condensation are correlated with biological activity. PMID:27240103

  16. 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…

  17. 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

  18. 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 ...

  19. Determination of osmium concentrations and (187)Os/(188)Os of crude oils and source rocks by coupling high-pressure, high-temperature digestion with sparging OsO(4) into a multicollector inductively coupled plasma mass spectrometer.

    PubMed

    Sen, Indra S; Peucker-Ehrenbrink, Bernhard

    2014-03-18

    The (187)Os/(188)Os ratio that is based on the β(-)-decay of (187)Re to (187)Os (t1/2 = 41.6 billion years) is widely used to investigate petroleum system processes. Despite its broad applicability to studies of hydrocarbon deposits worldwide, a suitable matrix-matched reference material for Os analysis does not exist. In this study, a method that enables Os isotope measurement of crude oil with in-line Os separation and purification from the sample matrix is proposed. The method to analyze Os concentration and (187)Os/(187)Os involves sample digestion under high pressure and high temperature using a high pressure asher (HPA-S, Anton Paar), sparging of volatile osmium tetroxide from the sample solution, and measurements using multicollector inductively coupled plasma mass spectrometry (MC-ICPMS). This methods significantly reduced the total procedural time compared to conventional Carius tube digestion followed by Os separation and purification using solvent extraction, microdistillation and N-TIMS analysis. The method yields Os concentration (28 ± 4 pg g(-1)) and (187)Os/(188)Os (1.62 ± 0.15) of commercially available crude oil reference material NIST 8505 (1 S.D., n = 6). The reference material NIST 8505 is homogeneous with respect to Os concentration at a test portion size of 0.2 g. Therefore, (187)Os/(188)Os composition and Os concentration of NIST 8505 can serve as a matrix-matched reference material for Os analysis. Data quality was assessed by repeated measurements of the USGS shale reference material SCo-1 (sample matrix similar to petroleum source rock) and the widely used Liquid Os Standard solution (LOsSt). The within-laboratory reproducibility of (187)Os/(188)Os for a 5 pg of LOsSt solution, analyzed with this method over a period of 12 months was ∼1.4% (1 S.D., n = 26), respectively. PMID:24552484

  20. A TinyOS-based wireless neural interface.

    PubMed

    Farshchi, Shahin; Mody, Istvan; Judy, Jack W

    2004-01-01

    The overlay of a neural interface upon a TinyOS-based sensing and communication platform is described. The system amplifies, digitally encodes, and transmits two EEG channels of neural signals from an un-tethered subject to a remote gateway, which routes the signals to a client PC. This work demonstrates the viability of the TinyOS-based sensor technology as a foundation for chronic remote biological monitoring applications, and thus provides an opportunity to create a system that can leverage from the frequent networking and communications advancements being made by the global TinyOS-development community. PMID:17271263

  1. 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.

  2. 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

  3. 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.

  4. Religiosidade, juventude e sexualidade: entre a autonomia e a rigidez1

    PubMed Central

    Silva, Cristiane Gonçalves da; Santos, Alessandro Oliveira; Licciardi, Daniele Carli; Paiva, Vera; Parker, Richard

    2009-01-01

    Esse artigo descreve como jovens religiosos e autoridades religiosas de sua comunidade compreendem a sexualidade, considerando suas experiências pessoais e como membros de comunidades religiosas. A análise pretende contribuir para que políticas públicas dedicadas à promoção da saúde sexual da juventude considerem a religiosidade, no contexto de um estado laico e da promoção do direito à prevenção. Foram realizadas 26 entrevistas abertas e semidirigidas em diferentes comunidades da região metropolitana da cidade de São Paulo (comunidades católicas, da umbanda, do candomblé e de diferentes denominações evangélicas) sobre iniciação sexual, casamento, gravidez, contracepção e prevenção das DST/Aids, homossexualidade, aborto e direitos humanos. Observou-se como jovens e autoridades religiosas convivem com a tensão entre tradição e modernidade e os distintos discursos sobre a sexualidade. Como sujeitos religiosos (do discurso religioso) e sujeitos sexuais (de discursos sobre sexualidade), devem ser incorporados pelos programas como sujeitos de direito nos termos de sua religiosidade. PMID:21886456

  5. 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.

  6. Os trigonum syndrome on bone SPECT/CT.

    PubMed

    Huang, Jianmin; Servaes, Sabah; Zhuang, Hongming

    2014-08-01

    A 16-year-old female athlete presented with increased pain in the distal left lower extremity. A possible stress fracture or shin splint of the left tibia was first considered. A 3-phase bone scintigraphy showed a very small focus of increased activity in the posterior left foot. A diagnosis of os trigonum syndrome was made after SPECT/CT images pinpointed the activity at the left os trigonum. PMID:24686218

  7. Neutron Capture Cross Sections for the Re/Os Clock

    SciTech Connect

    Mosconi, M.; Heil, M.; Kaeppeler, F.; Plag, R.; Voss, F.; Wisshak, K.; Mengoni, A.; Cennini, P.; Chiaveri, E.; Ferrari, A.; Fitzpatrick, L.; Herrera-Martinez, A.; Kadi, Y.; Sarchiapone, L.; Vlachoudis, V.; Wendler, H.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2005-05-24

    The radioactive decay of 187Re {yields} 187Os (t1/2 = 43 Gyr) is suited for dating the onset of heavy-element nucleosynthesis. The radiogenic contribution to the 187Os abundance is the difference between the natural abundance and the corresponding s-process component. This component can be obtained via the well-established {sigma}N systematics using the neighboring s-only isotope 186Os, provided the neutron-capture cross sections of both isotopes are known with sufficient accuracy. We report on a new set of experiments performed with a C6D6 detector array at the n{sub T}OF neutron spallation facility of CERN. The capture cross sections of 186Os, 187Os, and 188Os have been measured in the neutron-energy range between 1 eV and 1 MeV, and Maxwellian-averaged cross sections were deduced for the relevant thermal energies from kT=5 keV to 100 keV.

  8. Activation cross sections for 190Os( n, p) 190m,gRe, 188Os( n, p) 188Re and 190Os( n, n') 190mOs reactions from 13.5 to 14.8 MeV

    NASA Astrophysics Data System (ADS)

    Luo, Junhua; Zhang, Zhirong; Tian, Weisong; Tuo, Fei; Kong, Xiangzhong; Liu, Rong; Jiang, Li

    2009-04-01

    Cross sections for ( n, p) and ( n, n') reactions have been measured on osmium isotopes at the neutron energies from 13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Neutrons were produced via the 3H( d, n) 4He reaction using solid TiT. The neutron fluences were determined using the monitor reaction 93Nb( n,2 n) 92mNb. Data are reported for the following reactions: 190Os( n, p) 190mRe, 190Os( n, p) 190gRe, 190Os( n, p) 190Re, 188Os( n, p) 188Re and 190Os( n, n') 190mOs. Nuclear model calculations using the code HFTT, which employs the Hauser-Feshbach (statistical model) and exciton model (precompound effects) formalisms, were undertaken to describe the formation of the products. The cross sections were discussed and compared with experimental data found in the literature, with values of model calculations including the pre-equilibrium contribution, and with evaluation data of JEFF-3.1/A.

  9. 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.

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

    PubMed

    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

  12. 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.

  13. Marine 187Os/188Os isotope stratigraphy reveals the interaction of volcanism and ocean circulation during Oceanic Anoxic Event 2

    NASA Astrophysics Data System (ADS)

    Du Vivier, Alice D. C.; Selby, David; Sageman, Bradley B.; Jarvis, Ian; Gröcke, Darren R.; Voigt, Silke

    2014-03-01

    High-resolution osmium (Os) isotope stratigraphy across the Cenomanian-Turonian Boundary Interval from 6 sections for four transcontinental settings has produced a record of seawater chemistry that demonstrates regional variability as a function of terrestrial and hydrothermal inputs, revealing the impact of palaeoenvironmental processes. In every section the 187Os/188Os profiles show a comparable trend; radiogenic values in the lead up to Oceanic Anoxic Event 2 (OAE 2); an abrupt unradiogenic trend at the onset of OAE 2; an unradiogenic interval during the first part of OAE 2; and a return to radiogenic values towards the end of the event, above the Cenomanian-Turonian boundary. The unradiogenic trend in 187Os/188Os is synchronous in all sections. Previous work suggests that activity of the Caribbean LIP (Large Igneous Province) was the source of unradiogenic Os across the OAE 2 and possibly an instigator of anoxia in the oceans. Here we assess this hypothesis and consider the influence of activity from other LIPs; such as the High Arctic LIP. A brief shift to high radiogenic 187Os/188Os values occurred in the Western Interior Seaway before the onset of OAE 2. We evaluate this trend and suggest that a combination of factors collectively played critical roles in the initiation of OAE 2; differential input of nutrients from continental and volcanogenic sources, coupled with efficient palaeocirculation of the global ocean and epeiric seas, enhanced productivity due to higher nutrient availability, which permitted penecontemporaneous transport of continental and LIP-derived nutrients to trans-equatorial basins.

  14. Unique Features of Two Potassium Channels, OsKAT2 and OsKAT3, Expressed in Rice Guard Cells

    PubMed Central

    Hwang, Hyunsik; Yoon, Jinyoung; Kim, Hyun Yeong; Min, Myung Ki; Kim, Jin-Ae; Choi, Eun-Hye; Lan, Wenzhi; Bae, Young-Min; Luan, Sheng; Cho, Hana; Kim, Beom-Gi

    2013-01-01

    Potassium is the most abundant cation and a myriad of transporters regulate K+ homeostasis in plant. Potassium plays a role as a major osmolyte to regulate stomatal movements that control water utility of land plants. Here we report the characterization of two inward rectifying shaker-like potassium channels, OsKAT2 and OsKAT3, expressed in guard cell of rice plants. While OsKAT2 showed typical potassium channel activity, like that of Arabidopsis KAT1, OsKAT3 did not despite high sequence similarity between the two channel proteins. Interestingly, the two potassium channels physically interacted with each other and such interaction negatively regulated the OsKAT2 channel activity in CHO cell system. Furthermore, deletion of the C-terminal domain recovered the channel activity of OsKAT3, suggesting that the C-terminal region was regulatory domain that inhibited channel activity. Two homologous channels with antagonistic interaction has not been previously reported and presents new information for potassium channel regulation in plants, especially in stomatal regulation. PMID:23967316

  15. 187Re - 187Os Nuclear Geochronometry: Advancing Precambrian Chronostratigraphy

    NASA Astrophysics Data System (ADS)

    Roller, Goetz

    2015-04-01

    187Re - 187Os nuclear geochronometry is a newly developed dating method, which 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, using the IVREA nuclear geochronometer as one data point in a two-point-isochrone diagram. This chronometer is one of five terrestrial nuclear geochronometers identified so far [4]. It is based upon the peculiar and enigmatic isotopic Re-Os signature (Re/Os = 0.951, 187Os/188Os = 0.23211 ± 0.00018) from an Al-Augite Websterite dike within the Balmuccia Peridotite (Northern Italy) [5]. Constrained by nuclear theory and astrophysical evidence, the IVREA isotopic Re-Os signature may be explained as produced in a rapid (r) neutron-capture process around 3000 Ma ago [4]. Here, a TPI age is calculated for each of 9 drill core samples from a 20 m stratigraphic column (drill core ABDP-9, Astrobiology Drilling Program of the NASA Astrobiology Institute) of the Archean Mount McRae shales in Western Australia, which belong to the Pilbara Craton. An isochrone age of 2501.1 ± 8.2 Ma (187Os/188Osi = 0.04 ± 0.06, 95% CL) has previously been published for these 9 samples [6], using the open access computer program Isoplot [7] for the calculations. Therefore, the same program and data are used to test whether the results obtained by means of the new method meet the peer-reviewed results. As can be shown, all TPI ages are indeed consistent with the previously reported isochrone age. The same is true for the initial 187Os/188Osi ratios, which are in line with the enigmatic, extremely subchondritic initial ratio of 187Os/188Osi = 0.04 ± 0.06, constrained by the isochrone. TPI ages range from 2485 ± 66 Ma (187Os/188Osi = 0.0322 ± 0.0036, 95% CL) to 2519 ± 41 Ma (187Os/188Osi = 0.0312 ± 0.0035, 95% CL), with a mean value of 2501 ± 8.9 Ma (187Os/188Osi = 0.03267 ± 0.00073, 68% CL, n = 9

  16. 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.

  17. Interactions of Oryza sativa OsCONTINUOUS VASCULAR RING-LIKE 1 (OsCOLE1) and OsCOLE1-INTERACTING PROTEIN reveal a novel intracellular auxin transport mechanism.

    PubMed

    Liu, Fei; Zhang, Lan; Luo, Yanzhong; Xu, Miaoyun; Fan, Yunliu; Wang, Lei

    2016-10-01

    Little is known about the transport mechanism of intracellular auxin. Here, we report two vacuole-localized proteins, Oryza sativa OsCONTINUOUS VASCULAR RING-LIKE 1 (OsCOLE1) and OsCOLE1-INTERACTING PROTEIN (OsCLIP), that regulate intracellular auxin transport and homoeostasis. Overexpression of OsCOLE1 markedly increased the internode length and auxin content of the stem base, whereas these parameters were decreased in RNA interference (RNAi) plants. OsCOLE1 was localized on the tonoplast and preferentially expressed in mature tissues. We further identified its interacting protein OsCLIP, which was co-localized on the tonoplast. Protein-protein binding assays demonstrated that the N-terminus of OsCOLE1 directly interacted with OsCLIP in yeast cells and the rice protoplast. Furthermore, (3) H-indole-3-acetic acid ((3) H-IAA) transport assays revealed that OsCLIP transported IAA into yeast cells, which was promoted by OsCOLE1. The results indicate that OsCOLE1 affects rice development by regulating intracellular auxin transport through interaction with OsCLIP, which provides a new insight into the regulatory mechanism of intracellular transport of auxin and the roles of vacuoles in plant development. PMID:27265035

  18. 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.

  19. 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.

  20. "Os" omovertebrale variants prove it to be a misnomer.

    PubMed

    Solanki, Chirag; Bhat, Dhananjay I; Devi, Bhagavatula I

    2016-01-01

    There are only a few case reports comprising exclusively of os omovertebrale. Here, we discuss various types, varied clinical presentations, associated abnormalities, and management strategies of this abnormality. We retrospectively analyzed three patients with os omovertebrale and their clinical presentation, and also reviewed the limited available literature. Patients were evaluated clinically and radiologically to diagnose this abnormality as well as the associated abnormalities. Two patients were operated for neurological deficits attributed to this deformity. It is quite common to miss this abnormality when it is of osseocartilaginous or fibrous type, especially when it is asymptomatic and not associated with Sprengel's scapula. By analyzing our patients and other reported cases, we have proposed a classification system. In addition, we discuss varied clinical presentations and their practical application. Os omovertebrale is a rare abnormality. It should be kept in mind and managed when encountered in clinical practice. The classification and clinicoradiological correlations described here can be useful to individualize management issues. PMID:27625243

  1. 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.

  2. 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

  3. An Intercultural Education: Teaching Reading in a Mapuche Context

    ERIC Educational Resources Information Center

    Hernández, María Elena Mellado; Hermosilla, Adriana del Carmen Huaiquimil

    2015-01-01

    In Chile, there are currently intercultural educational policies; national curricula that assume updated research development including investigational advances in reading and opportunities for improvement of teacher training. However, in La Araucania Region predominates for lagging behind in reading and it is necessary to explain this tendency…

  4. 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).

  5. 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. PMID:25845672

  6. Hexagonal OsB2: Sintering, microstructure and mechanical properties

    DOE PAGESBeta

    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 ±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

  7. 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…

  8. 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. PMID:26826052

  9. Multiband superconductivity in Lu3Os4Ge13

    NASA Astrophysics Data System (ADS)

    Prakash, Om; Thamizhavel, A.; Ramakrishnan, S.

    2015-11-01

    Intermetallic R3T4X13 series consist of a cage-like structure and have attracted attention due to their unconventional electronic ground states. In this work, we report the normal and superconducting state properties of a high-quality single crystal of Lu3Os4Ge13. Lu3Os4Ge13 belongs to the above-mentioned series and crystallizes in a cubic crystal structure with the space group {\\text{}}{Pm}\\bar{3}n. Using electrical transport, magnetization and heat capacity measurements, we show that Lu3Os4Ge13 is a type-II multi-band superconductor (T c = 3.1 K) with unusual superconducting properties. The analysis of the low-temperature heat capacity data suggests that Lu3Os4Ge13 is a moderately coupled multi-band BCS superconductor with two gaps (2{{Δ }}/{k}B{T}c=3.68+/- 0.04\\\\&\\0.34+/- 0.02) in the superconducting state. The dc-magnetization (M-H) shows a large reversible region in the superconducting state similar to the vortex liquid phase observed in high-T c superconductors. The value of the Ginzburg number G i suggests that the thermal fluctuations, though small compared to those in high-T c cuprates, may play an important role in the unpinning of the vortices in this compound. The electronic band structure calculations show that three bands cross the Fermi level and constitute a complex Fermi surface in Lu3Os4Ge13.

  10. Vacuolar membrane transporters OsVIT1 and OsVIT2 modulate iron translocation between flag leaves and seeds in rice.

    PubMed

    Zhang, Yu; Xu, Yong-Han; Yi, Hong-Yin; Gong, Ji-Ming

    2012-11-01

    The plant vacuole is an important organelle for storing excess iron (Fe), though its contribution to increasing the Fe content in staple foods remains largely unexplored. In this study we report the isolation and functional characterization of two rice genes OsVIT1 and OsVIT2, orthologs of the Arabidopsis VIT1. Transient expression of OsVIT1:EGFP and OsVIT2:EGFP protein fusions revealed that OsVIT1 and OsVIT2 are localized to the vacuolar membrane. Ectopic expression of OsVIT1 and OsVIT2 partially rescued the Fe(2+) - and Zn(2+) -sensitive phenotypes in yeast mutant Δccc1 and Δzrc1, and further increased vacuolar Fe(2+) , Zn(2+) and Mn(2+) accumulation. These data together suggest that OsVIT1 and OsVIT2 function to transport Fe(2+) , Zn(2+) and Mn(2+) across the tonoplast into vacuoles in yeast. In rice, OsVIT1 and OsVIT2 are highly expressed in flag leaf blade and sheath, respectively, and in contrast to OsVIT1, OsVIT2 is highly responsive to Fe treatments. Interestingly, functional disruption of OsVIT1 and OsVIT2 leads to increased Fe/Zn accumulation in rice seeds and a corresponding decrease in the source organ flag leaves, indicating an enhanced Fe/Zn translocation between source and sink organs, which might represent a novel strategy to biofortify Fe/Zn in staple foods. PMID:22731699

  11. 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

  12. 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.

  13. 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.

  14. 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

    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

  15. 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

  16. 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.

  17. 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

  18. Determinação de elementos próprios dos asteróides troianos: comparação entre as teorias semi-analítica e sintética

    NASA Astrophysics Data System (ADS)

    Roig, F.; Beaugé, C.

    2003-08-01

    Além do cálculo semi-analítico de elementos próprios dos asteróides Troianos (Beaugé & Roig 2001, Icarus 153, 391), recentemente foi apresentado um novo conjunto destes elementos próprios determinado através de uma teoria sintética (Knenezevic & Milani 2003, comunicação pessoal). As bases de dados contendo estas determinações estão disponiveis na pagina web do Asteroid Dynamical Site (http://hamilton.dm.unipi.it/cgi-bin/astdys/astibo). Nesta comunicação apresentamos os primeiros resultados de um estudo comparativo entre ambos conjuntos de elementos próprios, analisando suas vantagens e desvantagens, assim como os limites de precisão de cada conjunto. Mostramos que os elementos próprios sintéticos são mais precisos que os smi-analíticos para grandes amplitudes de libração do ângulo s = l-lJup, embora acontece o contrario para os corpos cuja amplitude de libração é muito pequena. Finalmente discutimos a influencia destes erros na determinação de familias de asteroides e da estrutura resonante em torno dos pontos Lagrangeanos L4 e L5.

  19. 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.

  20. 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.

  1. 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

  2. Re-187 - Os-187 systematics in meteorites and cosmochemical consequences

    NASA Astrophysics Data System (ADS)

    Luck, J.-M.; Allegre, C. J.

    1983-03-01

    A new technique based on isotope dilution has allowed the reappraisal of Re-187 - Os-187 isotopic tracers. Rhenium and osmium were chemically separated and their isotopic compositions determined by ion-microprobe mass spectrometry. Such an approach led to the absolute dating of meteorites and allowed the estimation of the evolution of the Os isotopic composition in the earth's mantle. Having improved the analytical procedure and recalibrated the osmium spike, it is found that the value used previously was too high by a few per cent. Eight previous results on iron meteorites and on St Severin, corrected for this change in spike calibration, are therefore included here. Data now include 11 analyses on irons, and the iron phases of 10 chondrites and of one mesosiderite. From these data, a revised and more precise value for the rhenium decay constant is proposed, together with a new estimate for the age of the Galaxy.

  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. PMID:21619871

  4. 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.

  5. OsSPL13 controls grain size in cultivated rice.

    PubMed

    Si, Lizhen; Chen, Jiaying; Huang, Xuehui; Gong, Hao; Luo, Jianghong; Hou, Qingqing; Zhou, Taoying; Lu, Tingting; Zhu, Jingjie; Shangguan, Yingying; Chen, Erwang; Gong, Chengxiang; Zhao, Qiang; Jing, Yufeng; Zhao, Yan; Li, Yan; Cui, Lingling; Fan, Danlin; Lu, Yiqi; Weng, Qijun; Wang, Yongchun; Zhan, Qilin; Liu, Kunyan; Wei, Xinghua; An, Kyungsook; An, Gynheung; Han, Bin

    2016-04-01

    Although genetic diversity has a cardinal role in domestication, abundant natural allelic variations across the rice genome that cause agronomically important differences between diverse varieties have not been fully explored. Here we implement an approach integrating genome-wide association testing with functional analysis on grain size in a diverse rice population. We report that a major quantitative trait locus, GLW7, encoding the plant-specific transcription factor OsSPL13, positively regulates cell size in the grain hull, resulting in enhanced rice grain length and yield. We determine that a tandem-repeat sequence in the 5' UTR of OsSPL13 alters its expression by affecting transcription and translation and that high expression of OsSPL13 is associated with large grains in tropical japonica rice. Further analysis indicates that the large-grain allele of GLW7 in tropical japonica rice was introgressed from indica varieties under artificial selection. Our study demonstrates that new genes can be effectively identified on the basis of genome-wide association data. PMID:26950093

  6. Rice GDP-mannose pyrophosphorylase OsVTC1-1 and OsVTC1-3 play different roles in ascorbic acid synthesis.

    PubMed

    Qin, Hua; Deng, Zaian; Zhang, Chuanyu; Wang, Yayun; Wang, Juan; Liu, Hai; Zhang, Zhili; Huang, Rongfeng; Zhang, Zhijin

    2016-02-01

    GDP-D-mannose pyrophosphorylase (GMPase) catalyzes the synthesis of GDP-D-mannose, which is a precursor for ascorbic acid (AsA) synthesis in plants. The rice genome encodes three GMPase homologs OsVTC1-1, OsVTC1-3 and OsVTC1-8, but their roles in AsA synthesis are unclear. The overexpression of OsVTC1-1 or OsVTC1-3 restored the AsA synthesis of vtc1-1 in Arabidopsis, while that of OsVTC1-8 did not, indicating that only OsVTC1-1 and OsVTC1-3 are involved in AsA synthesis in rice. Similar to Arabidopsis VTC1, the expression of OsVTC1-1 was high in leaves, induced by light, and inhibited by dark. Unlike OsVTC1-1, the expression level of OsVTC1-3 was high in roots and quickly induced by the dark, while the transcription level of OsVTC1-8 did not show obvious changes under constant light or dark treatments. In OsVTC1-1 RNAi plants, the AsA content of rice leaves decreased, and the AsA production induced by light was limited. In contrast, OsVTC1-3 RNAi lines altered AsA synthesis levels in rice roots, but not in the leaves or under the light/dark treatment. The enzyme activity showed that OsVTC1-1 and OsVTC1-3 had higher GMPase activities than OsVTC1-8 in vitro. Our data showed that, unlike in Arabidopsis, the rice GPMase homologous proteins illustrated a new model in AsA synthesis: OsVTC1-1 may be involved in the AsA synthesis, which takes place in leaves, while OsVTC1-3 may be responsible for AsA synthesis in roots. The different roles of rice GMPase homologous proteins in AsA synthesis may be due to their differences in transcript levels and enzyme activities. PMID:26715595

  7. 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. PMID:18218894

  8. On acoplamento mecânico entre a antena e o transdutor no detector de ondas gravitacionais Mario Schenberg

    NASA Astrophysics Data System (ADS)

    Melo, J. L.; Aguiar, O. D.; Velloso, W. F., Jr.; Lucena, A. U.

    2003-08-01

    O detector de ondas gravitacionais MARIO SCHENBERG consistirá de uma massa esférica de cobre-alumínio de 1150kg resfriada a 4K, sobre a qual serão instalados 6 transdutores de nióbio. Com estes trandutores pretende-se converter um possível sinal de onda gravitacional detectado em sinal elétrico, para tanto é necessário que o acoplamento mecânico entre os transdutores e a massa ressonante seja o maior possível. Isto significa que o transdutor deve ser ressonante na mesma freqüência que a antena (aproximadamente 3200Hz). Neste trabalho foi desenvolvida uma geometria para a estrutura mecânica do trandutor. Isto foi feito criando-se modelos em elementos finitos usando-se o "software" MSC/Nastran. Estes modelos criados foram analisados estaticamente (cálculo de tensões) e dinamicamente (cálculo das freqüências de ressonâncias e seus respectivos modos normais) de maneira a se obter o primeiro modo normal do transdutor em 3200Hz. A partir destes cálculos escolheu-se a melhor geometria para o transdutor. Os próximos passos do trabalho serão: usinar este transdutor em uma barra de nióbio e testá-lo à temperatura ambiente e à baixa temperatura. Após isto, pretende-se testá-lo na própria antena resfriada.

  9. 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.

  10. 186Os and 187Os enrichments and high-3He/4He sources in the Earth’s mantle: Evidence from Icelandic picrites

    NASA Astrophysics Data System (ADS)

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

    2007-09-01

    Picrites from the neovolcanic zones in Iceland display a range in 187Os/ 188Os from 0.1297 to 0.1381 (γ Os = + 2.1 to +8.7) and uniform 186Os/ 188Os of 0.1198375 ± 32 (2 σ). The value for 186Os/ 188Os 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 186Os/ 188Os and 187Os/ 188Os 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 3He/ 4He, 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 187Os/ 188Os and 3He/ 4He from 9.6 to 19 Ra in Iceland picrites is best modeled as mixtures of 1 Ga or older ancient recycled crust mixed with primitive mantle or incompletely degassed depleted mantle isolated since 1-1.5 Ga, which preserves the high 3He/ 4He of the depleted mantle at the time. These mixtures create a hybrid source region that subsequently mixes with the present-day convecting MORB mantle during ascent and melting. This multistage mixing scenario requires convective isolation in the deep mantle for hundreds of million years or more to maintain these compositionally distinct hybrid sources. The 3He/ 4He 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 compositional gaps between the different aged lavas when 3He/ 4He is plotted versus various geochemical parameters such as 143Nd/ 144Nd and La/Sm. These relationships can be interpreted as an increase in the proportion of ancient recycled crust in the upwelling plume over this time period. The positive correlation between 187Os/ 188Os and

  11. 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

  12. Synthesis, Structure, and Magnetic Properties of Sr2NiOsO6 and Ca2NiOsO6: Two New Osmium-Containing Double Perovskites

    SciTech Connect

    Macquart,R.; Kim, S.; Gemmill, W.; Stalick, J.; Lee, Y.; Vogt, Tzur Loye, H.

    2005-01-01

    Two new double perovskite oxides, Ca{sub 2}NiOsO{sub 6}and Sr{sub 2}NiOsO{sub 6}, have been prepared as polycrystalline powders by solid state synthesis. The two oxides were structurally characterized by variable-temperature powder neutron diffraction. Ca{sub 2}NiOsO{sub 6} was found to adopt a monoclinic structure (P2{sub 1}/n), while Sr{sub 2}NiOsO{sub 6} was found to be tetragonal (I4/m). Magnetic susceptibility measurements indicate that Ca2NiOsO6 orders in a canted antiferromagnetic state at about 175 K while Sr{sub 2}NiOsO{sub 6} orders antiferromagnetically at about 50 K.

  13. 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.

  14. 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.

  15. 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.

  16. Shape difference implied by quenched Coriolis interaction in 175Os

    NASA Astrophysics Data System (ADS)

    Dracoulis, G. D.; Fabricius, B.

    1990-06-01

    Chance near degeneracy of rotational states in the 1/2-[521] and 5/2-[512] bands in 175Os leads to mixing and connecting E2 transitions. Analysis of the observed branching ratios gives an interaction matrix element of about 4 keV, an order of magnitude smaller than the expected Coriolis interaction, deduced from particle-rotor calculations. A difference in deformation of 25% between the two configurations, as suggested by the larger unperturbed moment of inertia in the 1/2-[521] band, would explain the quenched interaction.

  17. Angle dependence of Shubnikov-de Haas effect of filled skutterudite compounds CeOs4Sb12 and NdOs4Sb12

    NASA Astrophysics Data System (ADS)

    Ho, P.-C.; Singleton, J.; Balakirev, F. F.; Maple, M. B.; Yanagisawa, T.

    Intriguingly the three filled skutterudite compounds CeOs4Sb12, PrOs4Sb12, and NdOs4Sb12 span the range from the Kondo insulator with a 1K antiferromagnetic (AFM) order, a 1.85K unconventional superconductor (SC), to a 1K mean-field type ferromagnet (FM), indicating that they reside near quantum critical points of AFM and FM with unconventional SC induced within this regime. Therefore, understanding the Fermi surfaces of NdOs4Sb12 and CeOs4Sb12 becomes crucial in elucidating the superconducting pairing mechanism in PrOs4Sb12. Penetration depths of single crystals of CeOs4Sb12 and NdOs4Sb12 were measured for temperatures down to 1.3 K and magnetic fields up to 60 tesla by using proximity detection oscillators in the Pulsed Field Facility at NHMFL/LANL. Angle dependence of Shubnikov-de Haas oscillations was detected for rotating the field with respect to the crystalline orientations [010] and [0-10]. The results indicate that LaOs4Sb12, PrOs4Sb12 and NdOs4Sb12 have similar Fermi surfaces. The Fermi surface of CeOs4Sb12 is rather isotropic and is much different from the other three compounds. Research at CSU-Fresno is supported by NSF DMR-1506677; at UCSD by NSF DMR-1206553 and US DOE DE-FG02-04ER46105; at NHMFL by DOE, NSF, and FL; at Hokkaido U by Graint-In-Aid No. 2600342,Jpn.

  18. OsPhyA modulates rice flowering time mainly through OsGI under short days and Ghd7 under long days in the absence of phytochrome B.

    PubMed

    Lee, Yang-Seok; Yi, Jakyung; An, Gynheung

    2016-07-01

    Phytochromes recognize light signals and control diverse developmental processes. In rice, all three phytochrome genes-OsphyA, OsphyB, and OsphyC-are involved in regulating flowering time. We investigated the role of OsPhyA by comparing the osphyA osphyB double mutant to an osphyB single mutant. Plants of the double mutant flowered later than the single under short days (SD) but bolted earlier under long days (LD). Under SD, this delayed-flowering phenotype was primarily due to the decreased expression of Oryza sativa GIGANTEA (OsGI), which controls three flowering activators: Heading date 1 (Hd1), OsMADS51, and Oryza sativa Indeterminate 1 (OsId1). Under LD, although the expression of several repressors, e.g., Hd1, Oryza sativa CONSTANS-like 4 (OsCOL4), and AP2 genes, was affected in the double mutant, that of Grain number, plant height and heading date 7 (Ghd7) was the most significantly reduced. These results indicated that OsPhyA influences flowering time mainly by affecting the expression of OsGI under SD and Ghd7 under LD when phytochrome B is absent. We also demonstrated that far-red light delays flowering time via both OsPhyA and OsPhyB. PMID:27039184

  19. Painful os Acromiale: Conservative Management in a Young Swimmer Athlete

    PubMed Central

    Frizziero, Antonio; Benedetti, Maria G.; Creta, Domenico; Moio, Antonio; Galletti, Stefano; Maffulli, Nicola

    2012-01-01

    An os acromiale (OA) arises from a fusion failure of the anterior acromial apophysis. This case report presents the successful management of a painful OA associated to rotator cuff impingement in a competitive swimmer, based on ultrasonographic diagnosis and conservative management. Rest from sport activity, oral anti-inflammatory drugs and previous attempt of treatment of shoulder pain were ineffective. After two months of conservative treatment consisting of avoidance of swimming, local anti-inflammatory, physical therapy with ice, strengthening exercises with elastic bands to strengthen the scapular stabilizing muscles, rotator cuff and lowering humeral head muscles, the patient was pain free and all specific clinical tests for impingement syndrome (Neer, Hawkins, Whipple and Yocum tests) were negative. Digital compression of the OA site was not painful, and the Jobe and Palm-up tests were negative. The athlete returned to swim continuing the rehabilitation exercises, and the successful results were maintained at one year follow up. An unstable and symptomatic OA can be easily diagnosed with ultrasound exam. Rehabilitation for rotator cuff tendinopathies or/and bursitis can be a valid alternative to surgery. Key pointsAn os acromiale (OA) arises from a fusion failure of the anterior acromial apophysis.A correct diagnosis of OA associated to rotator cuff impingement can be performed by ultrasonographic exam.A conservative management of rotator cuff impingement syndrome, associated to OA, can be planned in athletic patients as a valid alternative to surgery. PMID:24149210

  20. Muonic x-ray study of the even Os nuclei

    NASA Astrophysics Data System (ADS)

    Hoehn, M. V.; Shera, E. B.; Wohlfahrt, H. D.; Yamazaki, Y.; Steffen, R. M.; Sheline, R. K.

    1981-10-01

    Precision measurements have been made of the muonic x-ray spectra of the transitional nuclei 186,188,190,192Os. Equivalent Barrett radii and isotope shifts have been determined, as have isomer shifts of the first excited 2+ states. These results are compared with other experiments and with theoretical calculations. The systematics of isotope shifts in the deformed nuclei are also discussed. Generalized E 2 moments of the charge distribution have been extracted in a nearly model-independent way and conventional electromagnetic moments have been deduced by assuming a specific transition charge density model. The latter are in good agreement with recent calculations of both the interacting boson approximation and the boson expansion theory. However, a serious discrepancy in the values of the quadrupole moments determined from the muonic and Coulomb excitation experiments is apparent. The model dependence of the muonic results (including the effect of a triaxial model charge distribution) is explored as a possible cause of the discrepancy; however, no effect large enough to explain the discrepancy is found. Furthermore, no feature of the muonic spectra was found which could be used to distinguish between a triaxial and an axially symmetric charge distribution. NUCLEAR STRUCTURE 186,188,190,192Os; measured muonic x-ray spectra; deduced monopole and quadrupole charge parameters, isotope and isomer shifts.

  1. Overexpression of OsDof12 affects plant architecture in rice (Oryza sativa L.)

    PubMed Central

    Wu, Qi; Li, Dayong; Li, Dejun; Liu, Xue; Zhao, Xianfeng; Li, Xiaobing; Li, Shigui; Zhu, Lihuang

    2015-01-01

    Dof (DNA binding with one finger) proteins, a class of plant-specific transcription factors, are involved in plant growth and developmental processes and stress responses. However, their biological functions remain to be elucidated, especially in rice (Oryza sativa L.). Previously, we have reported that OsDof12 can promote rice flowering under long-day conditions. Here, we further investigated the other important agronomical traits of the transgenic plants overexpressing OsDof12 and found that overexpressing OsDof12 could lead to reduced plant height, erected leaf, shortened leaf blade, and smaller panicle resulted from decreased primary and secondary branches number. These results implied that OsDof12 is involved in rice plant architecture formation. Furthermore, we performed a series of Brassinosteroid (BR)-responsive tests and found that overexpression of OsDof12 could also result in BR hyposensitivity. Of note, in WT plants the expression of OsDof12 was found up-regulated by BR treatment while in OsDof12 overexpression plants two positive BR signaling regulators, OsBRI1 and OsBZR1, were significantly down-regulated, indicating that OsDof12 may act as a negative BR regulator in rice. Taken together, our results suggested that overexpression of OsDof12 could lead to altered plant architecture by suppressing BR signaling. Thus, OsDof12 might be used as a new potential genetic regulator for future rice molecular breeding. PMID:26500670

  2. A Combined He and Os Isotopic Study of the HSDP-2 Core from Mauna Kea, Hawaii

    NASA Astrophysics Data System (ADS)

    Ireland, T. J.; Walker, R. J.; Depaolo, D. J.; Kurz, M. D.

    2004-12-01

    Combined osmium and helium isotope systematics of hotspot lavas have the potential to reveal information about the deep Earth. A high 3He/4He ratio may represent an undegassed reservoir, generally associated with the lower mantle. There are two Os isotopes that can be studied to help to further elucidate the problem. The decay of 187Re to 187Os is the more frequently cited system; however, in terms of lower mantle processes, the decay of 190Pt to 186Os may be extremely useful. Both of these Os isotopes are enriched in the core relative to chondritic values. In a previous study, Brandon et al. (1999) examined several Hawaiian volcanoes for both He and Os isotopes. A correlation was noted between the 3He/4He, 187Os/188Os and 186Os/188Os ratios. In terms of 3He/4He and 187Os/188Os space, the three commonly cited Hawaiian end-members (Kea, Koolau and Loihi members) were clearly defined. A strong positive correlation was also observed for 186Os/188Os versus 3He/4He. These correlations were interpreted as a possible signature of core-mantle interaction. There were some limitations to previous studies. Only 2-3 samples from each volcano were studied, with these samples generally being subaerially erupted. The He data utilized were often not for the same samples for which the Os data were collected (volcano averages for He were used on some samples). With the introduction of data from the Hawaiian Scientific Drilling Project (HSDP-2), which drilled 2.84 km into the Mauna Kea volcanics (DePaolo et al., 2000), an extensive history of a single volcano can be observed (from the early submarine stages to the later subaerial rocks). In the current study a detailed Os isotopic analysis of several samples that span a large depth range of the HSDP-2 core, in conjunction with previously collected He isotopic data (Kurz et al., 2004), was conducted. The samples define a relatively narrow range of slightly suprachondritic 187Os/188Os ratios (0.12865-0.13056), despite having a large

  3. 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

  4. 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

  5. Over-expression of OsPIN2 leads to increased tiller numbers, angle and shorter plant height through suppression of OsLAZY1.

    PubMed

    Chen, Yingnan; Fan, Xiaorong; Song, Wenjing; Zhang, Yali; Xu, Guohua

    2012-02-01

    Crop architecture parameters such as tiller number, angle and plant height are important agronomic traits that have been considered for breeding programmes. Auxin distribution within the plant has long been recognized to alter architecture. The rice (Oryza sativa L.) genome contains 12 putative PIN genes encoding auxin efflux transporters, including four PIN1 and one PIN2 genes. Here, we report that over-expression of OsPIN2 through a transgenic approach in rice (Japonica cv. Nipponbare) led to a shorter plant height, more tillers and a larger tiller angle when compared with wild type (WT). The expression patterns of the auxin reporter DR5::GUS and quantification of auxin distribution showed that OsPIN2 over-expression increased auxin transport from the shoot to the root-shoot junction, resulting in a non-tissue-specific accumulation of more free auxin at the root-shoot junction relative to WT. Over-expression of OsPIN2 enhanced auxin transport from shoots to roots, but did not alter the polar auxin pattern in the roots. Transgenic plants were less sensitive to N-1-naphthylphthalamic acid, an auxin transport inhibitor, than WT in their root growth. OsPIN2-over-expressing plants had suppressed the expression of a gravitropism-related gene OsLazy1 in the shoots, but unaltered expression of OsPIN1b and OsTAC1, which were reported as tiller angle controllers in rice. The data suggest that OsPIN2 has a distinct auxin-dependent regulation pathway together with OsPIN1b and OsTAC1 controlling rice shoot architecture. Altering OsPIN2 expression by genetic transformation can be directly used for modifying rice architecture. PMID:21777365

  6. 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.

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

    PubMed

    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

  8. Novel rice MAP kinases OsMSRMK3 and OsWJUMK1 involved in encountering diverse environmental stresses and developmental regulation.

    PubMed

    Agrawal, Ganesh K; Agrawal, Shyam K; Shibato, Junko; Iwahashi, Hitoshi; Rakwal, Randeep

    2003-01-17

    We report isolation of two novel rice (Oryza sativa L.) mitogen-activated protein kinases (MAPKs), OsMSRMK3 (multiple stress responsive) and OsWJUMK1 (wound- and JA-uninducible) that most likely exist as single copy genes in its genome. OsMSRMK3 and OsWJUMK1 encode 369 and 569 amino acid polypeptides having the MAPK family signature and phosphorylation activation motifs TEY and TDY, respectively. Steady state mRNA analyses of these MAPKs with constitutive expression in leaves of two-week-old seedlings revealed that OsMSRMK3 was up-regulated upon wounding (by cut), jasmonic acid (JA), salicylic acid (SA), ethylene, abscisic acid, hydrogen peroxide (H(2)O(2)), protein phosphatase inhibitors, chitosan, high salt/sugar, and heavy metals, whereas OsWJUMK1 not induced by either wounding, JA or SA, showed up-regulation only by H(2)O(2), heavy metals, and cold stress (12 degrees C). Moreover, these MAPKs were developmentally regulated. These results strongly suggest a role for OsMSRMK3 and OsWJUMK1 in both stress-signalling pathways and development in rice. PMID:12507518

  9. 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

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

    PubMed

    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

    2016-03-01

    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. The Diagnosis of the Os Trigonum Syndrome with a Fluoroscopically Controlled Injection of Local Anesthetic

    PubMed Central

    Jones, Darron M; Saltzman, Charles L; El-Khoury, George

    1999-01-01

    Purpose To report the results of excision of the os trigonum using a fluoroscopically controlled injection of local anesthetic to diagnose the os trigonum syndrome. Design and patients Os trigonum syndrome is a recognized cause of pain in the posterior aspect of the foot and ankle. The symptoms and physical findings, however, are often nonspecific and difficult to differentiate from other causes of posterior ankle pain. We report four patients with persistent posterolateral ankle pain despite prolonged nonoperative treatment. An os trigonal syndrome was diagnosed by a positive response to a fluoroscopically guided local anesthetic injection in the region of synchondrosis between the os trigonum and the posterior talus. Results All four patients underwent excision of the os trigonum with complete resolution of symptoms and return to full activity. Conclusions Fluoroscopically controlled injection can help confirm the suspected diagnosis of an os trigonum syndrome and may have positive predictive value regarding the outcome of excisional surgery. PMID:10847526

  12. Global structure search and physical properties of Os2C.

    PubMed

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

    2016-09-14

    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. PMID:27400877

  13. An OS9-UNIX data acquisition system with ECL readout

    SciTech Connect

    Ziem, P.; Beschorner, C.; Bohne, W.; Drescher, B.; Friese, T.; Kiehne, T.; Kluge, C.

    1996-02-01

    A new data acquisition system has been developed at the Hahn-Meitner-Institut to handle almost 550 parameters of nuclear physics experiments. The system combines a UNIX host running a portable data buffer router and a VME front-end based on the OS9 real time operating system. Different kinds of pulse analyzers are located in several CAMAC crates which are controlled by the VME system via a VICbus connection. Data readout is performed by means of an ECL daisy chain. Besides controlling CAMAC the main purpose of the VME front-end is event data formatting and histogramming. Using TCP/IP services, the UNIX host receives formatted data packages for data storage and display. During a beam time at the antiproton accelerator LEAR/CERN, the PS208 experiment has accumulated about 100 Gbyte of event data.

  14. 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.

  15. Brief Announcement: An OS Architecture for Device Self-protection

    NASA Astrophysics Data System (ADS)

    He, Ruan; Lacoste, Marc; Leneutre, Jean

    By introducing context-awareness in the system layer, pervasive computing is a turning point in OS design. Device mobility and dynamicity of situations raise strong challenges for run-time adaptability of embedded software, while at the same time inducing new, serious threats to device security. Paradoxically, due to the multiplicity of protection requirements specific to each environment illustrated by the heterogeneity of network security policies, the solution may come from applying context-awareness to security itself. The idea is to tune security mechanisms to match the protection needs of the current device environment, such as the estimated level of risk. A manual adaptation is ruled out by the administration overhead and error potential of human intervention. To automate reconfiguration, security needs to be autonomic [2]. But how?

  16. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest Their Role in Abiotic Stress Response.

    PubMed

    Bhattacharjee, Annapurna; Khurana, Jitendra P; Jain, Mukesh

    2016-01-01

    Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22, and OsHOX24. These genes were highly up-regulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA), auxin, salicylic acid, and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/T)ATTG) and AH2 (CAAT(C/G)ATTG). Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses. PMID:27242831

  17. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest Their Role in Abiotic Stress Response

    PubMed Central

    Bhattacharjee, Annapurna; Khurana, Jitendra P.; Jain, Mukesh

    2016-01-01

    Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22, and OsHOX24. These genes were highly up-regulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA), auxin, salicylic acid, and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/T)ATTG) and AH2 (CAAT(C/G)ATTG). Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses. PMID:27242831

  18. Sr2OsO5 and Sr7Os4O19, Two Structurally Related, Mott Insulating Osmates(VI) Exhibiting Substantially Reduced Spin Paramagnetic Response.

    PubMed

    Mohitkar, Shrikant A; Schnelle, Walter; Felser, Claudia; Jansen, Martin

    2016-08-15

    The new osmates(VI), Sr2OsO5 and Sr7Os4O19, feature quasi-1-D polyoxo anions, consisting of corner sharing [OsO6] octahedra. In both compounds, the magnetic moment at T = 300 K is significantly lower (1.2-1.3 μB/Os-atom) than the value expected for S = 1. For neither of the new osmates(VI) is any evidence for long-range magnetic order found. For Sr7Os4O19, magnetic susceptibility suggests an antiferromagnetic ordering at TN = 43(3) K; however, no corresponding anomaly is visible in specific heat. Both compounds are semiconductors. PMID:27479609

  19. Uma Comparação entre Técnicas de Propagação de Erros em Astrofísica: Monte Carlo x Bootstrap

    NASA Astrophysics Data System (ADS)

    Zabot, Alexandre; Baptista, Raymundo

    2005-07-01

    Neste trabalho é feito um estudo comparativo entre dois algoritmos numéricos usados para propagação de erros em dados experimentais. Um deles é conhecido por Método de Monte carlo e o outro por Método de Bootstrap. Recentemente, Dhullon & Watson argüiram que a aplicação do método de Monte Carlo introduz ruído nos dados, e propuseram então a utilização do Bootstrap como alternativa capaz de produzir resultados superiores. O objetivo deste trabalho é testar a validade dessa afirmação. As duas técnicas foram aplicadas a três problemas diferentes: o ajsute de modelos de emissão LTE simples e atmosfera estelar a espectros estelares observados e o ajuste de curvas de luz de eclipses de Variáveis Cataclísmicas para a detemrinação da distribuição radial de brilho dos seus discos de acréscimo. Os métodos foram testados quanto à sua robusteza, ou seja, a capacidade de prover resultados coerentes enre si. Além disso, as soluções dos métodos foram comparadas. Os resultados indicam que não existe evidência de superioridade de um métodos em relação ao outro.

  20. Hypoxia Associated Proteolytic Processing of OS-9 by the Metalloproteinase Meprin β

    PubMed Central

    Martin, Barry Lee; Conley, Sabena Michelle; Harris, Regine Simone; Stanley, Corshe Devon

    2016-01-01

    Meprin metalloproteases play a role in the pathology of ischemia/reperfusion- (IR-) induced renal injury. The endoplasmic reticulum-associated protein, osteosarcoma-9 (OS-9), has been shown to interact with the carboxyl-terminal tail of meprin β. More importantly, OS-9 interacts with the hypoxia inducible factor-1α (HIF-1α) and the prolyl-hydroxylase, proteins which mediate the cell's response to hypoxia. To determine if OS-9 is a meprin substrate, kidney proteins from meprin αβ knockout mice (αβKO) (which lack endogenous meprins) and purified human OS-9 were incubated with activated forms of meprin A and meprin B, and Western blot analysis was used to evaluate proteolytic processing of OS-9. Fragmentation of OS-9 was observed in reactions with meprin B, but not meprin A. To determine whether meprin B cleaves OS-9 in vivo, wild-type (WT) and meprin αβKO mice were subjected to IR-induced renal injury. Fragmentation of OS-9 was observed in kidney proteins from WT mice subjected to IR, but not in meprin αβKO counterparts. Transfection of kidney cells (MDCK and HEK293) with meprin β cDNA prevented accumulation of OS-9 following exposure to the hypoxia mimic, CoCl2. These data suggest that meprin β interaction with OS-9 plays a role in the hypoxia response associated with IR-induced renal injury. PMID:27478637

  1. Heterogeneous Os isotope compositions in the Kalatongke sulfide deposit, NW China: the role of crustal contamination

    NASA Astrophysics Data System (ADS)

    Gao, Jian-Feng; Zhou, Mei-Fu; Lightfoot, Peter C.; Qu, Wenjun

    2012-10-01

    Re-Os isotope compositions of mantle-derived magmas are highly sensitive to crustal contamination because the crust and mantle have very different Os isotope compositions. Crustal contamination may trigger S saturation and thus the formation of magmatic Ni-Cu-(PGE) sulfide deposits. The ˜287-Ma Kalatongke norite intrusion of NW China are hosted in carboniferous tuffaceous rocks and contain both disseminated and massive sulfide mineralization. The Re-Os isotope compositions in the intrusion are highly variable. Norite and massive sulfide ores have γ Os values ranging from +59 to +160 and a Re-Os isochron age of 239 ± 51 Ma, whereas disseminated sulfide ores have γ Os values from +117 to +198 and a Re-Os isochron age of 349 ± 34 Ma. The variability of Os isotope compositions can be explained as the emplacement of two distinct magma pulses. Massive sulfide ores and barren norite in the intrusion formed from the same magma pulse, whereas the disseminated sulfide ores with more radiogenic Os isotopes formed from another magma pulse which underwent different degrees of crustal contamination. Re-Os isotopes may not be suitable for dating sulfide-bearing intrusions that underwent variable degrees of crustal contamination to form magmatic sulfide deposits.

  2. Hypoxia Associated Proteolytic Processing of OS-9 by the Metalloproteinase Meprin β.

    PubMed

    Martin, Barry Lee; Conley, Sabena Michelle; Harris, Regine Simone; Stanley, Corshe Devon; Niyitegeka, Jean-Marie Vianney; Ongeri, Elimelda Moige

    2016-01-01

    Meprin metalloproteases play a role in the pathology of ischemia/reperfusion- (IR-) induced renal injury. The endoplasmic reticulum-associated protein, osteosarcoma-9 (OS-9), has been shown to interact with the carboxyl-terminal tail of meprin β. More importantly, OS-9 interacts with the hypoxia inducible factor-1α (HIF-1α) and the prolyl-hydroxylase, proteins which mediate the cell's response to hypoxia. To determine if OS-9 is a meprin substrate, kidney proteins from meprin αβ knockout mice (αβKO) (which lack endogenous meprins) and purified human OS-9 were incubated with activated forms of meprin A and meprin B, and Western blot analysis was used to evaluate proteolytic processing of OS-9. Fragmentation of OS-9 was observed in reactions with meprin B, but not meprin A. To determine whether meprin B cleaves OS-9 in vivo, wild-type (WT) and meprin αβKO mice were subjected to IR-induced renal injury. Fragmentation of OS-9 was observed in kidney proteins from WT mice subjected to IR, but not in meprin αβKO counterparts. Transfection of kidney cells (MDCK and HEK293) with meprin β cDNA prevented accumulation of OS-9 following exposure to the hypoxia mimic, CoCl2. These data suggest that meprin β interaction with OS-9 plays a role in the hypoxia response associated with IR-induced renal injury. PMID:27478637

  3. 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.

  4. Os isotopes in hornblende-bearing intra-plate alkaline lavas (Central European Volcanic Province; CEVP)

    NASA Astrophysics Data System (ADS)

    Mayer, B.; Jung, S.; Brauns, M.; Pfänder, J.

    2013-12-01

    Previous Os isotope studies on CEVP lavas have shown that samples with the lowest Os isotopic composition (init. 187Os/188Os: 0.132-0.135) have the highest Os concentrations (70-93 ppt). These isotope ratios are higher than those usually proposed for the lithospheric upper mantle with inferred subchondritic 187Os/188Os ratios but are similar to 187Os/188Os ratios found in lithospheric peridotite xenoliths from the CEVP. Lower Os concentrations of other lavas from the CEVP (6-43 ppt) are correlated with radiogenic init. 187Os/188Os ratios up to 0.469 and are best explained by AFC processes involving lower crustal rocks. Fairly primitive samples of high-TiO2 alkaline hornblende-bearing lavas from the Rhön area (CEVP) with MgO up to 10.4 wt% have a large range in their Os isotopic composition (init. 187Os/188Os: 0.268-0.552; 15-30 ppt Os) exceeding the range observed in other intraplate basalts including OIB. Fractionated samples have distinctly more radiogenic Os (init. 187Os/188Os: up to 0.890; 3-10 ppt Os) isotopic compositions. For most samples, uniform Nd, Sr, and Pb isotope data are not consistent with AFC processes, hence, the radiogenic Os isotopic composition is also unlikely to result from assimilation processes alone. Some samples with radiogenic Os isotopic compositions and low Os concentrations have radiogenic 87Sr/86Sr, unradiogenic 143Nd/144Nd, and unradiogenic Pb isotope ratios suggesting contamination with crustal material in this case. Energy-constrained AFC calculations involving previously used hypothetical crustal endmembers show that for the majority of the hornblende-bearing lavas crustal contamination is unlikely. An alternative view would be that the mantle source of the hornblende-bearing lavas contains significant portions of non-peridoditic (i.e. pyroxenitic) material. Pyroxenites can have elevated Re/Os ratios and may evolve towards radiogenic Os isotopic compositions over time. New high-precision 40Ar-39Ar ages on hornblende from these

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

    PubMed

    Zhang, Baowen; Wang, Xiaolong; Zhao, Zhiying; Wang, Ruiju; Huang, Xiahe; Zhu, Yali; Yuan, Li; Wang, Yingchun; Xu, Xiaodong; Burlingame, Alma L; Gao, Yingjie; Sun, Yu; Tang, Wenqiang

    2016-02-01

    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

  6. Shubnikov-de Haas Effect measured on single crystals of CeOs4 Sb 12 and NdOs4 Sb 12 along the high symmetry directions

    NASA Astrophysics Data System (ADS)

    Ho, P.-C.; Singleton, J.; Maple, M. B.; Shrekenhamer, D. B.; X., Lee; Thale, A.; Yanagisawa, T.

    2011-03-01

    The filled skutterudite compounds CeOs 4 Sb 12 , PrOs 4 Sb 12 , and NdOs 4 Sb 12 are respectively a 1~K antiferromagnetic (AFM) Kondo insulator, a 1.85~K unconventional superconductor, and a 1~K mean-field type ferromagnet (FM), suggesting that superconductivity in PrOs 4 Sb 12 may result from proximity to AFM and FM quantum-critical points. Fermi-surface measurements of NdOs 4 Sb 12 and CeOs 4 Sb 12 could therefore give insights into the pairing mechanism. We have used a MHz skin-depth technique to observe Shubnikov-de Haas oscillations (SdHos) in single crystals of these materials at fields of up to 60~T. In CeOs 4 Sb 12 for H [001], a previously-unobserved semimetal-to-metal transition was detected at ~ 25 ~T; above this, a series of SdHos with a frequency of 1700~T and mCR ~ 3.6me emerge. For H [011] in NdOs 4 Sb 12 , a single series of SdHos, frequency ~ 874 ~T, was found. These may correspond to the β band in PrOs 4 Sb 12 , but with a much smaller mCR ~ 1.5me . Research at CSU-Fresno is supported by RC CCSA # 7669 and the start-up fund; at NHMFL by DOE, NSF, and FL.; at UCSD by NSF # 0802478 and US DOE DE FG02-04ER46105; at Hokkaido U by MEXT, Japan.

  7. 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

  8. 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

  9. Similarity-regulation of OS-EM for accelerated SPECT reconstruction.

    PubMed

    Vaissier, P E B; Beekman, F J; Goorden, M C

    2016-06-01

    Ordered subsets expectation maximization (OS-EM) is widely used to accelerate image reconstruction in single photon emission computed tomography (SPECT). Speedup of OS-EM over maximum likelihood expectation maximization (ML-EM) is close to the number of subsets used. Although a high number of subsets can shorten reconstruction times significantly, it can also cause severe image artifacts such as improper erasure of reconstructed activity if projections contain few counts. We recently showed that such artifacts can be prevented by using a count-regulated OS-EM (CR-OS-EM) algorithm which automatically adapts the number of subsets for each voxel based on the estimated number of counts that the voxel contributed to the projections. While CR-OS-EM reached high speed-up over ML-EM in high-activity regions of images, speed in low-activity regions could still be very slow. In this work we propose similarity-regulated OS-EM (SR-OS-EM) as a much faster alternative to CR-OS-EM. SR-OS-EM also automatically and locally adapts the number of subsets, but it uses a different criterion for subset regulation: the number of subsets that is used for updating an individual voxel depends on how similar the reconstruction algorithm would update the estimated activity in that voxel with different subsets. Reconstructions of an image quality phantom and in vivo scans show that SR-OS-EM retains all of the favorable properties of CR-OS-EM, while reconstruction speed can be up to an order of magnitude higher in low-activity regions. Moreover our results suggest that SR-OS-EM can be operated with identical reconstruction parameters (including the number of iterations) for a wide range of count levels, which can be an additional advantage from a user perspective since users would only have to post-filter an image to present it at an appropriate noise level. PMID:27206135

  10. Similarity-regulation of OS-EM for accelerated SPECT reconstruction

    NASA Astrophysics Data System (ADS)

    Vaissier, P. E. B.; Beekman, F. J.; Goorden, M. C.

    2016-06-01

    Ordered subsets expectation maximization (OS-EM) is widely used to accelerate image reconstruction in single photon emission computed tomography (SPECT). Speedup of OS-EM over maximum likelihood expectation maximization (ML-EM) is close to the number of subsets used. Although a high number of subsets can shorten reconstruction times significantly, it can also cause severe image artifacts such as improper erasure of reconstructed activity if projections contain few counts. We recently showed that such artifacts can be prevented by using a count-regulated OS-EM (CR-OS-EM) algorithm which automatically adapts the number of subsets for each voxel based on the estimated number of counts that the voxel contributed to the projections. While CR-OS-EM reached high speed-up over ML-EM in high-activity regions of images, speed in low-activity regions could still be very slow. In this work we propose similarity-regulated OS-EM (SR-OS-EM) as a much faster alternative to CR-OS-EM. SR-OS-EM also automatically and locally adapts the number of subsets, but it uses a different criterion for subset regulation: the number of subsets that is used for updating an individual voxel depends on how similar the reconstruction algorithm would update the estimated activity in that voxel with different subsets. Reconstructions of an image quality phantom and in vivo scans show that SR-OS-EM retains all of the favorable properties of CR-OS-EM, while reconstruction speed can be up to an order of magnitude higher in low-activity regions. Moreover our results suggest that SR-OS-EM can be operated with identical reconstruction parameters (including the number of iterations) for a wide range of count levels, which can be an additional advantage from a user perspective since users would only have to post-filter an image to present it at an appropriate noise level.

  11. Characterization of mouse model-derived osteosarcoma (OS) cells in vitro and in vivo.

    PubMed

    Uluçkan, Özge; Bakiri, Latifa; Wagner, Erwin F

    2015-01-01

    Osteosarcoma (OS) is the most common primary tumor of bone with a high incidence in children. Treatment options for OS are limited, and once metastasized, the prognosis is very poor. Genetically engineered mouse models (GEMMs) are valuable tools to understand the mechanisms of tumorigenesis and to test possible therapies. In this chapter, we summarize the methods related to the isolation, characterization, and transplantation of OS cells obtained from GEMMs. PMID:25636475

  12. 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

  13. OsMADS32 interacts with PI-like proteins and regulates rice flower development.

    PubMed

    Wang, Huanhuan; Zhang, Liang; Cai, Qiang; Hu, Yun; Jin, Zhenming; Zhao, Xiangxiang; Fan, Wei; Huang, Qianming; Luo, Zhijing; Chen, Mingjiao; Zhang, Dabing; Yuan, Zheng

    2015-05-01

    OsMADS32 is a monocot specific MIKC(c) type MADS-box gene that plays an important role in regulating rice floral meristem and organs identity, a crucial process for reproductive success and rice yield. However, its underlying mechanism of action remains to be clarified. Here, we characterized a hypomorphic mutant allele of OsMADS32/CFO1, cfo1-3 and identified its function in controlling rice flower development by bioinformatics and protein-protein interaction analysis. The cfo1-3 mutant produces defective flowers, including loss of lodicule identity, formation of ectopic lodicule or hull-like organs and decreased stamen number, mimicking phenotypes related to the mutation of B class genes. Molecular characterization indicated that mis-splicing of OsMADS32 transcripts in the cfo1-3 mutant resulted in an extra eight amino acids in the K-domain of OsMADS32 protein. By yeast two hybrid and bimolecular fluorescence complementation assays, we revealed that the insertion of eight amino acids or deletion of the internal region in the K1 subdomain of OsMADS32 affects the interaction between OsMADS32 with PISTILLATA (PI)-like proteins OsMADS2 and OsMADS4. This work provides new insight into the mechanism by which OsMADS32 regulates rice lodicule and stamen identity, by interaction with two PI-like proteins via its K domain. PMID:25081486

  14. Hexagonal OsB2 reduction upon heating in H2 containing environment

    DOE PAGESBeta

    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/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

  15. 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.

  16. Transformed yeast (Schizosaccharomyces pombe) overexpressing rice Tau class glutathione S-transferase (OsGSTU30 and OsGSTU41) shows enhanced resistance to hexavalent chromium.

    PubMed

    Tripathi, Ankita; Indoliya, Yuvraj; Tiwari, Madhu; Tiwari, Poonam; Srivastava, Dipali; Verma, Pankaj kumar; Verma, Shikha; Gautam, Neelam; Chakrabarty, Debasis

    2014-08-01

    Extensive use of hexavalent chromium [Cr(VI)] in leather tanning, stainless-steel production, wood preservatives and electroplating industries has resulted in widespread environmental pollution and poses a serious threat to human health. A plant's response to Cr(VI) stress results in growth inhibition and toxicity leading to changes in components of antioxidant systems. In a previous study, we observed that a large number of glutathione S-transferase (GST) genes were up-regulated under Cr(VI) stress in rice. In this study, two rice root-specific Tau class GST genes (OsGSTU30 and OsGSTU41) were introduced into yeast (Schizosaccharomyces pombe). Transformed yeast cells overexpressing OsGSTU30 and OsGSTU41 had normal growth, but had much higher levels of GST activities and showed enhanced resistance to Cr(VI) as compared to control cells (transformed with empty vector). Also, a higher accumulation of chromium was found in the transformed yeast cells as compared to the control cells. Manipulation of glutathione biosynthesis by exogenous application of buthionine sulfoximine abolishes the protective effect of OsGSTs against Cr(VI) stress. These results suggest that Tau class OsGSTs play a significant role in detoxification of Cr(VI), probably by chelating and sequestrating glutathione-Cr(VI) complexes into vacuoles. PMID:24968244

  17. Two Rice Authentic Histidine Phosphotransfer Proteins, OsAHP1 and OsAHP2, Mediate Cytokinin Signaling and Stress Responses in Rice1[C][W

    PubMed Central

    Sun, Lijing; Zhang, Qian; Wu, Jinxia; Zhang, Liqing; Jiao, Xuewen; Zhang, Shengwei; Zhang, Zhiguo; Sun, Daye; Lu, Tiegang; Sun, Ying

    2014-01-01

    Cytokinin plays an important role in plant development and stress tolerance. Studies of Arabidopsis (Arabidopsis thaliana) have demonstrated that cytokinin acts through a two-component system that includes a histidine (His) kinase, a His phosphotransfer protein (HP), and a response regulator. Phylogenetic analyses have revealed the conservation of His kinases but lineage-specific expansion of HPs and response regulators in rice (Oryza sativa). However, whether the functions of rice HPs have diverged remains unknown. In this study, two rice authentic HPs (OsAHP1 and OsAHP2) were knocked down simultaneously via RNA interference (RNAi), and the transgenic OsAHP-RNAi plants exhibited phenotypes expected for a deficiency in cytokinin signaling, including dwarfism with reduced internode lengths, enhanced lateral root growth, early leaf senescence, and reduced tiller numbers and fertility under natural conditions. The OsAHP-RNAi seedlings were also hyposensitive to exogenous cytokinin. Furthermore, OsAHP-RNAi seedlings were hypersensitive to salt treatment but resistant to osmotic stress relative to wild-type plants. These results indicate that OsAHPs function as positive regulators of the cytokinin signaling pathway and play different roles in salt and drought tolerance in rice. PMID:24578505

  18. A radiogenic Os component in the oceanic lithosphere? Constraints from Hawaiian pyroxenite xenoliths

    NASA Astrophysics Data System (ADS)

    Sen, Indra Sekhar; Bizimis, Michael; Sen, Gautam; Huang, Shichun

    2011-09-01

    Platinum Group Element (PGE) concentrations in garnet pyroxenite xenoliths from Oahu, Hawaii, are significantly lower than those in mantle peridotites and show fractionated patterns (e.g. Pd N/Os N = 2-10, Pd N/Ir N = 4-24; N = chondrite normalized) and very high Re N/Os N ratios (˜9-248). Mass balance calculations show that the bulk rock pyroxenite PGE inventory is controlled by the presence of sulfide phases. The 187Os/ 188Os ratios of these pyroxenites vary from subchondritic to suprachondritic (0.123-0.164); and the 187Os/ 188Os ratios show good correlations with bulk rock and clinopyroxene major and trace element compositions, and bulk rock PGE and sulfur abundances. These observations suggest that the Os isotope compositions in these pyroxenites largely reflect primary processes in the oceanic mantle and Pacific lithosphere. In contrast, bulk rock 187Os/ 188Os ratios do not correlate with other lithophile isotopic tracers (e.g. Rb-Sr, Sm-Nd, Lu-Hf) which show limited isotopic variability ( Bizimis et al., 2005). This and the lack of 187Os/ 188Os vs. Re/Os correlations suggest that the range in Os isotope ratios is not likely the result of mixing between long-lived depleted and enriched components or aging of these pyroxenites within the Pacific lithosphere after its formation at a mid-oceanic ridge setting some 80-100 million years ago. We interpret the Os isotopes, PGE and lithophile element systematics as the result of melt-lithosphere interaction at the base of the Pacific lithosphere. The major and trace element systematics of the clinopyroxenes and bulk rock pyroxenites and the relatively constant lithophile element isotope systematics are best explained by fractional crystallization of a rather homogenous parental magma. We suggest that during melt crystallization and percolation within the lithosphere, the parental pyroxenite melt assimilated radiogenic Os from the grain boundaries of the peridotitic lithosphere. This radiogenic Os component may

  19. 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

  20. OsDMC1 Is Not Required for Homologous Pairing in Rice Meiosis1[OPEN

    PubMed Central

    Tang, Ding; Liu, Xiaofei; Du, Guijie; Shen, Yi; Li, Yafei; Cheng, Zhukuan

    2016-01-01

    Meiotic homologous recombination is pivotal to sexual reproduction. DMC1, a conserved recombinase, is involved in directing single-end invasion between interhomologs during meiotic recombination. In this study, we identified OsDMC1A and OsDMC1B, two closely related proteins in rice (Oryza sativa) with high sequence similarity to DMC1 proteins from other species. Analysis of Osdmc1a and Osdmc1b Tos17 insertion mutants indicated that these genes are functionally redundant. Immunolocalization analysis revealed OsDMC1 foci occurred at leptotene, which disappeared from late pachytene chromosomes in wild-type meiocytes. According to cytological analyses, homologous pairing is accomplished in the Osdmc1a Osdmc1b double mutant, but synapsis is seriously disrupted. The reduced number of bivalents and abnormal OsHEI10 foci in Osdmc1a Osdmc1b establishes an essential role for OsDMC1 in crossover formation. In the absence of OsDMC1, early recombination events probably occur normally, leading to normal localization of γH2AX, PAIR3, OsMRE11, OsCOM1, and OsRAD51C. Moreover, OsDMC1 was not detected in pairing-defective mutants, such as pair2, pair3, Oscom1, and Osrad51c, while it was loaded onto meiotic chromosomes in zep1, Osmer3, Oszip4, and Oshei10. Taken together, these results suggest that during meiosis, OsDMC1 is dispensable for homologous pairing in rice, which is quite different from the DMC1 homologs identified so far in other organisms. PMID:26960731

  1. OsDMC1 Is Not Required for Homologous Pairing in Rice Meiosis.

    PubMed

    Wang, Hongjun; Hu, Qing; Tang, Ding; Liu, Xiaofei; Du, Guijie; Shen, Yi; Li, Yafei; Cheng, Zhukuan

    2016-05-01

    Meiotic homologous recombination is pivotal to sexual reproduction. DMC1, a conserved recombinase, is involved in directing single-end invasion between interhomologs during meiotic recombination. In this study, we identified OsDMC1A and OsDMC1B, two closely related proteins in rice (Oryza sativa) with high sequence similarity to DMC1 proteins from other species. Analysis of Osdmc1a and Osdmc1b Tos17 insertion mutants indicated that these genes are functionally redundant. Immunolocalization analysis revealed OsDMC1 foci occurred at leptotene, which disappeared from late pachytene chromosomes in wild-type meiocytes. According to cytological analyses, homologous pairing is accomplished in the Osdmc1a Osdmc1b double mutant, but synapsis is seriously disrupted. The reduced number of bivalents and abnormal OsHEI10 foci in Osdmc1a Osdmc1b establishes an essential role for OsDMC1 in crossover formation. In the absence of OsDMC1, early recombination events probably occur normally, leading to normal localization of γH2AX, PAIR3, OsMRE11, OsCOM1, and OsRAD51C. Moreover, OsDMC1 was not detected in pairing-defective mutants, such as pair2, pair3, Oscom1, and Osrad51c, while it was loaded onto meiotic chromosomes in zep1, Osmer3, Oszip4, and Oshei10 Taken together, these results suggest that during meiosis, OsDMC1 is dispensable for homologous pairing in rice, which is quite different from the DMC1 homologs identified so far in other organisms. PMID:26960731

  2. Os Isotope Heterogeneity of the Convecting Upper Mantle: The Mayari-Baracoa Ophiolitic Belt (Eastern Cuba)

    NASA Astrophysics Data System (ADS)

    Frei, R.; Gervilla, F.; Meibom, A.; Proenza, J. A.

    2005-12-01

    Chromite separates from a set of historically important chromite deposits from the 90 Ma old Mayarí-Baracoa Ophiolitic Belt in eastern Cuba were inspected for Re-Os isotopic systematics in an attempt to quantify the extent of Os isotopic heterogeneities within a restricted upper mantle portion represented by a single ophiolite. Compositional variations of chromites indicate their crystallization from hydrous melts varying in composition from back-arc basin basalts (Al-rich chromites; Cr# = 0.43-0.55; low Pd/Ir) to boninites (Cr-rich chromites; Cr# = 0.60-0.83; high Pd/Ir) in a supra-subduction zone setting. Initial Os isotopic compositions of the studied chromites can be grouped according to their distribution in 3 regional districts. Results indicate systematically negative calculated initial γOs values varying from -1.06 ± 0.79 (Moa-Baracoa district), -1.77 ± 0.80 (Sagua de Tanamo district) and -2.79 ± 0.31 (Mayari district). These suprachondritic values are distinctly (3.5-5.2%) less radiogenic than the estimated minimum 187Os/188Os composition of the primitive upper mantle of 0.1296 ± 8 and can be explained by Re depletion during ancient partial melting and melt percolation events. Old Os isotope model ages (<2100 Ma)of some of the chromites (or platinum-group minerals included in them) show and confirm previous findings that ancient Os isotopic signatures can survive in the Earth's upper mantle. Our systematically negative initial γOs values do not improve the definition of an already statistically poorly defined present-day Os isotopic composition of the convecting upper mantle, but instead indicate a complex history for the convecting upper mantle which precludes the calculation of a uniform regional Os isotopic signature for this reservoir.

  3. Correlated cosmogenic W and Os isotopic variations in Carbo and implications for Hf-W chronology

    NASA Astrophysics Data System (ADS)

    Qin, Liping; Dauphas, Nicolas; Horan, Mary F.; Leya, Ingo; Carlson, Richard W.

    2015-03-01

    An obstacle for establishing the chronology of iron meteorite formation using 182Hf-182W systematics (t1/2 = 8.9 Myr) is to find proper neutron fluence monitors to correct for cosmic ray modification of W isotopic composition. Recent studies showed that siderophile elements such as Pt and Os could serve such a purpose. To test and calibrate these neutron dosimeters, the isotopic compositions of W and Os were measured in a slab of the IID iron meteorite Carbo. This slab has a well-characterized noble gas depth profile reflecting different degrees of shielding to cosmic rays. The results show that W and Os isotopic ratios correlate with distance from the pre-atmospheric center. Negative correlations, barely resolved within error, were found between ε190Os-ε189Os and ε186Os-ε189Os with slopes of -0.64 ± 0.45 and -1.8(+1.9/-2.1), respectively. These Os isotope correlations broadly agree with model predictions for capture of secondary neutrons produced by cosmic ray irradiation and results reported previously for other groups of iron meteorites. Correlations were also found between ε182W-ε189Os (slope = 1.02 ± 0.37) and ε182W-ε190Os (slope = -1.38 ± 0.58). Intercepts of these two correlations yield pre-exposure ε182W values of -3.32 ± 0.51 and -3.62 ± 0.23, respectively (weighted average ε182W = -3.57 ± 0.21). This value relies on a large extrapolation leading to a large uncertainty but gives a metal-silicate segregation age of -0.5 ± 2.4 Myr after formation of the solar system. Combining the iron meteorite measurements with simulations of cosmogenic effects in iron meteorites, equations are presented to calculate and correct for cosmogenic effects on 182W using Os isotopes.

  4. 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

  5. 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

  6. 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

  7. 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

  8. Os trigonum. Variation of a common accessory ossicle of the talus.

    PubMed

    Mann, R W; Owsley, D W

    1990-10-01

    The authors present a pictorial essay showing the range of variability of separate and attached os trigona in dry-bone specimens. The presence of free os trigona is found to be 1.7% in an early 20th-century skeletal sample, with no findings of the trait in 513 tali of prehistoric native Americans and Eskimos. PMID:2269922

  9. 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.…

  10. 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…

  11. Role of OsHAL3 protein, a putative 4'-phosphopantothenoylcysteine decarboxylase in rice.

    PubMed

    Zhang, Ning; Wang, Xuechen; Chen, Jia

    2009-01-01

    In this study, we cloned the OsHAL3 gene from rice Oryza sativa. Alignment analysis revealed that OsHAL3 has a high sequence identity to Dfp protein in Escherichia coli and AtHAL3a protein in Arabidopsis thaliana, which have 4'-phosphopantothenoylcysteine decarboxylase (PPC-DC) activity. OsHAL3 can complement mutation in the E. coli dfp gene encoding PPC-DC, so that the mutant strains with OsHAL3 can grow on rich media at 42 degrees C and on VB minimal media at 30 degrees C. Complementation tests with point mutations of OsHAL3 suggested that the conserved Cys176 residue of OsHAL3 is a key active-site residue. The mutant OsHAL3 G180A has a partly reduced activity. Related mRNA-level analysis showed that the OsHAL3 gene is induced by calcium pantothenate in rice. PMID:19232050

  12. 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. PMID:22057936

  13. Functional analysis of OsPGIP1 in rice sheath blight resistance.

    PubMed

    Wang, Rui; Lu, Liaoxun; Pan, Xuebiao; Hu, Zongliang; Ling, Fei; Yan, Yan; Liu, Yemao; Lin, Yongjun

    2015-01-01

    As one of the most devastating diseases of rice, sheath blight causes severe rice yield loss. However, little progress has been made in rice breeding for sheath blight resistance. It has been reported that polygalacturonase inhibiting proteins can inhibit the degradation of the plant cell wall by polygalacturonases from pathogens. Here, we prokaryotically expressed and purified OsPGIP1 protein, which was verified by Western blot analysis. Activity assay confirmed the inhibitory activity of OsPGIP1 against the PGase from Rhizoctonia solani. In addition, the location of OsPGIP1 was determined by subcellular localization. Subsequently, we overexpressed OsPGIP1 in Zhonghua 11 (Oryza sativa L. ssp. japonica), and applied PCR and Southern blot analysis to identify the positive T0 transgenic plants with single-copy insertions. Germination assay of the seeds from T1 transgenic plants was carried out to select homozygous OsPGIP1 transgenic lines, and the expression levels of OsPGIP1 in these lines were analyzed by quantitative real-time PCR. Field testing of R. solani inoculation showed that the sheath blight resistance of the transgenic rice was significantly improved. Furthermore, the levels of sheath blight resistance were in accordance with the expression levels of OsPGIP1 in the transgenic lines. Our results reveal the functions of OsPGIP1 and its resistance mechanism to rice sheath blight, which will facilitate rice breeding for sheath blight resistance. PMID:25488398

  14. 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

  15. Radiometric dating of marine-influenced coal using Re-Os geochronology

    NASA Astrophysics Data System (ADS)

    Tripathy, Gyana Ranjan; Hannah, Judith L.; Stein, Holly J.; Geboy, Nicholas J.; Ruppert, Leslie F.

    2015-12-01

    Coal deposits are integral to understanding the structural evolution and thermal history of sedimentary basins and correlating contemporeous estuarine and fluvial delatic strata with marine sections. While marine shales may readily lend themselves to Re-Os dating due to the dominance of hydrogenous Re and Os, the lack of a chronometer for near-shore sedimentary environments hampers basinwide correlations in absolute time. Here, we employ the Re-Os geochronometer, along with total organic carbon (TOC) and Rock-Eval data, to determine the timing and conditions of a marine incursion at the top of the Matewan coal bed, Kanawha Formation, Pottsville Group, West Virginia, USA. The observed range for hydrogen index (HI: 267-290 mg hydrocarbon/gram total organic carbon) for these coal samples suggests dominance of aliphatic hydrocarbons with low carbon (Os (0.52 ± 0.09 ng /g) concentrations of the marine-influenced Matewan coal are higher by few orders of magnitude than published data for terrestrial coal. A Re-Os isochron for the Matewan coal provides an age of 325 ± 14 Ma (Model 3; MSWD = 12; n = 19; 2σ). This is the first Re-Os age derived from coal samples; the age overlaps a new composite Re-Os age of 317 ± 2 Ma for the immediately overlying Betsie Shale Member. External precision for replicate Os analyses carried out for several Matewan coal samples shows a positive correlation with their HI. The HI, which is low in terrestrial organic matter, reflects the degree of marine influence. Thus, samples with the most profound marine influence also have the best analytical reproducibility. Equilibration of Os isotopes with seawater under marine conditions overwhelms variability inherited from terrestrial plant debris, decreasing scatter on the isochron. The 187Re/188Os ratios of the Matewan coal (˜3300-5135) are higher than most of those previously published for Phanerozoic black shale (mostly <2000). Mass

  16. 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).

  17. OsSPL14 promotes panicle branching and higher grain productivity in rice.

    PubMed

    Miura, Kotaro; Ikeda, Mayuko; Matsubara, Atsushi; Song, Xian-Jun; Ito, Midori; Asano, Kenji; Matsuoka, Makoto; Kitano, Hidemi; Ashikari, Motoyuki

    2010-06-01

    Identification of alleles that improve crop production and lead to higher-yielding varieties are needed for food security. Here we show that the quantitative trait locus WFP (WEALTHY FARMER'S PANICLE) encodes OsSPL14 (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 14, also known as IPA1). Higher expression of OsSPL14 in the reproductive stage promotes panicle branching and higher grain yield in rice. OsSPL14 controls shoot branching in the vegetative stage and is affected by microRNA excision. We also demonstrate the feasibility of using the OsSLP14(WFP) allele to increase rice crop yield. Introduction of the high-yielding OsSPL14(WFP) allele into the standard rice variety Nipponbare resulted in increased rice production. PMID:20495564

  18. 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

  19. OsZIP5 is a plasma membrane zinc transporter in rice.

    PubMed

    Lee, Sichul; Jeong, Hee Joong; Kim, Sun A; Lee, Joohyun; Guerinot, Mary Lou; An, Gynheung

    2010-07-01

    Zinc is essential for normal plant growth and development. To understand its transport in rice, we characterized OsZIP5, which is inducible under Zn deficiency. OsZIP5 complemented the growth defect of a yeast Zn-uptake mutant, indicating that OsZIP5 is a Zn transporter. The OsZIP5-GFP fusion protein was localized to the plasma membrane. Transgenic plants overexpressing the gene grew less well. Overexpression of the gene decreased the Zn concentration in shoots, but caused it to rise in the roots. Knockout plants showed no visible phenotypic changes under either normal or deficient conditions. However, they were tolerant to excess Zn and contained less Zn. In contrast, overexpressing transgenics were sensitive to excess Zn. These results indicate that OsZIP5 plays a role in Zn distribution within rice. PMID:20419467

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

    PubMed

    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

  1. 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.

  2. Effects of pressure and composition on Pt-Re-Os partitioning behavior between solid and liquid metal in the Fe-Ni-S system: Implication for Os isotopic anomalies in plume-derived lavas

    NASA Astrophysics Data System (ADS)

    Hayashi, H.; Ohtani, E.; Terasaki, H.; Ito, Y.

    2008-12-01

    Coupled 186Os/188Os and 187Os/188Os enrichments of plume-derived lavas have been suggested to reflect material contribution from the outer core (e.g., Brandon, 1998). This geochemical hypothesis is based on an assumption that the outer core shows coupled enrichments in 186Os/ 188Os and 187Os/ 188Os ratio, reflecting the decay of 190Pt and 187Re to 186Os and 187Os, respectively. In order to examine this hypothesis, partitioning experiments of Pt-Re-Os between solid metal and liquid metal were performed using an MA-8 Kawai-type multi-anvil apparatus at 5-20 GPa and 1250-1400C. Starting materials of Fe metal, Ni (7 wt.%) metal and FeS (5 wt.% S in the bulk) were doped with 3 wt.% of Pt, Re and Os metals. Concentrations of all elements were determined using JXA-8800M electron probe microanalyzer with wave-dispersive spectrometry. Measured partition coefficients of Pt, Re and Os increase with increasing sulfur content and almost constant with increasing pressure. Therefore, the effect of liquid composition on the partitioning behavior of highly siderophile elements is much more significant compared to the effect of pressure and temperature. On the basis of the present experimental results, it is unlikely to generate the required Pt-Re-Os fractionation during inner core crystallization assuming that the light element in the Earth"fs core is sulfur only.

  3. 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.

  4. 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. PMID:20347221

  5. s-Process Os isotope enrichment in ureilites by planetary processing

    NASA Astrophysics Data System (ADS)

    Goderis, S.; Brandon, A. D.; Mayer, B.; Humayun, M.

    2015-12-01

    Ubiquitous nucleosynthetic isotope anomalies relative to the terrestrial isotopic composition in Mo, Ru, and other elements are known from both bulk chondrites and differentiated meteorites, but Os isotope ratios reported from such meteorites have been found to be indistinguishable from the terrestrial value. The carriers of s- and r-process Os must thus have been homogeneously distributed in the solar nebula. As large Os isotope anomalies are known from acid leachates and residues of primitive chondrites, the constant relative proportions of presolar s- and r-process carriers in such chondrites must have been maintained during nebular processes. It has long been assumed that partial melting of primitive chondrites would homogenize the isotopic heterogeneity carried by presolar grains. Here, ureilites, carbon-rich ultramafic achondrites dominantly composed of olivine and low-Ca pyroxene, are shown to be the first differentiated bulk Solar System materials for which nucleosynthetic Os isotope anomalies have been identified. These anomalies consist of enrichment in s-process Os heterogeneously distributed in different ureilites. Given the observed homogeneity of Os isotopes in all types of primitive chondrites, this Os isotope variability among ureilites must have been caused by selective removal of s-process-poor Os host phases, probably metal, during rapid localized melting on the ureilite parent body. While Mo and Ru isotope anomalies for all meteorites measured so far exhibit s-process deficits relative to the Earth, the opposite holds for the Os isotope anomalies in ureilites reported here. This might indicate that the Earth preferentially accreted olivine-rich restites and inherited a s-process excess relative to smaller meteorite bodies, consistent with Earth's high Mg/Si ratio and enrichment of s-process nuclides in Mo, Ru, and Nd isotopes. Our new Os isotope results imply that caution must be used when applying nucleosynthetic isotope anomalies as provenance

  6. 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.

  7. Osmium isotopic compositions of Os-rich platinum group element alloys from the Klamath and Siskiyou Mountains

    NASA Astrophysics Data System (ADS)

    Meibom, Anders; Frei, Robert; Sleep, Norman H.

    2004-02-01

    We present new measurements of 186Os/188Os and 187Os/188Os in 10 Os-rich platinum group element (PGE) alloys from placer deposits formed by the mechanical erosion of peridotite-bearing ophiolites in the Klamath and Siskiyou Mountains in northern California and southwestern Oregon. These data nearly double our database of high-precision 186Os/188Os measurements on such samples. Together with previously published data, our new results reinforce the conclusion that the radiogenic 186Os/188Os compositions of these PGE alloys are very difficult to reconcile with a derivation of their Os from the outer core. Such a model requires extremely early growth of the inner core to its present size, within several hundred million years after accretion of the Earth, which is geophysically implausible. Collectively, our data suggest instead that partial melting or metasomatic processes in the upper mantle play a primary role in controlling the Os isotopic systematics of these Os-rich PGE alloys and suggest the existence of upper mantle components characterized by radiogenic 186Os/188Os ratios. Pyroxene-rich lithologies are possible candidates.

  8. La problematica de la demarcacion entre ciencia y pseudociencia y sus implicaciones en la educacion cientifica

    NASA Astrophysics Data System (ADS)

    Jimenez Tolentino, Dinorah

    2011-12-01

    En la sociedad prevalece una tendencia generalizada hacia la inclusion de creencias y practicas pseudocientificas. Esta investigacion responde a la necesidad de analizar como la proliferacion de las pseudociencias afecta la vision que tienen los estudiantes universitarios sobre las ciencias naturales. A tales efectos, la investigadora describe las concepciones epistemologicas que tienen los estudiantes sobre las ciencias y las pseudociencias e identifica los criterios de demarcacion, entre un area y otra, que se derivan de estas concepciones. De igual modo, esta identifica las creencias y practicas pseudocientificas de mayor arraigo entre los estudiantes, destacando, a su vez, la razon de ser de las mismas. Por ultimo, la investigadora analiza las implicaciones educativas de la problematica de la demarcacion entre ciencia y pseudociencia. La investigacion es de naturaleza mixta, enmarcada en los paradigmas empirico- analitico y cualitativo. El proceso investigativo se llevo a cabo mediante la administracion del cuestionario Criterios para la demarcacion entre ciencia y pseudociencia. La parte cualitativa estuvo enmarcada en el diseno de estudio de caso, recopilando informacion mediante entrevistas semiestructuradas en dos grupos focales. La poblacion de estudio estuvo constituida por estudiantes universitarios del nivel subgraduado de la Universidad Central de Bayamon. Los resultados del estudio reflejaron las concepciones erroneas de los estudiantes sobre la naturaleza de las ciencias y las pseudociencias. Con respecto a la demarcacion entre ciencia y pseudociencia, el criterio imperante entre los universitarios es el de la verificabilidad, considerando la aplicacion del metodo cientifico como el metodo para demostrar la veracidad de las teorias cientificas. Las creencias y practicas pseudocientificas no son muy frecuentes entre los universitarios. Estos atribuyen las mismas a la prevalencia de elementos supersticiosos y al engano a que es sometida la poblacion

  9. 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.

  10. Neutron physics of the Re/Os clock. II. The (n,n') cross section of Os187 at 30 keV neutron energy

    NASA Astrophysics Data System (ADS)

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

    2010-07-01

    The inelastic neutron-scattering cross section of Os187 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 Li7(p,n)Be7 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 Os187 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 Os187/Re187 pair as a cosmochronometer.

  11. Comparison of Re-Os Systematics Between the Nonmagmatic and Magmatic Iron Meteories

    NASA Astrophysics Data System (ADS)

    Wang, G. Q.; Peng, L.; Xu, J. F.

    2014-12-01

    Re-Os system is a valuable tool for understanding the origin and crystallization sequence of asteroidal cores, and the evolution of HSE in other planetary cores. In the past several decades, numerous Re-Os data of magmatic iron meteorites have been published, but few for nonmagmatic iron meteorites. The nonmagmatic iron meteorites experienced incomplete melt, therefore they cannot represent the asteroidal core samples. It is ambiguous question for the origin and crystallization process of nonmagmatic iron meteorites. In this study, 10 iron meteorites have been analyzed by the high-precision NTIMS (TRITON) Faraday cup static measurement through using isotopic dilution method. Among 10 iron meteorites studied here, 3 samples of group ⅢAB and one sample of group ⅢE belong to magmatic iron meteorites. Another 3 samples of groupⅠAB and 3 samples of group ⅢCD are nonmagmatic iron meteorites. The precision is ≤ 20 ppm 2σ for 187Os/188Os and blank of Re and Os is < 80 pg. In the 187Os/188Os, 187Re/188Os isochron diagram, the 3 ⅢAB and a ⅢE samples define a straight best-fit line corresponding to a slope of 0.07917±0.00062 and an intercept with the vertical axis of 0.09575±0.00038. The rang of 187Re/188Os ratios is from 0.460391 to 0.691148. Application of a λ for 187Re=1.666×10-11 yr-1 yields an age of 4590±37 Ma. In error rang, this age is consistent with reported Re-Os isochron age of 4558±12 Ma. The large uncertainty likely result from small number data. 3 samples of groupⅠAB in this study produce a slope of 0.07904±0.00011, and initial 187Os/188Os of 0.09663±0.00005, corresponding to T=4582.6±6.4Ma, which is older than the published data for theⅠA, 4529±23Ma, and 4537±21 Ma. Another 3 samples of group ⅢCD also defined a slop of 0.07315±0.00073, and initial 187Os/188Os of 0.09873±0.00038, the age calculation is 4253±44 Ma. 187Os/188Os ratios vary rather narrow (the biggest difference is 0.087) in the 6 nonmagmatic iron meteorites

  12. OsWRKY53, a versatile switch in regulating herbivore-induced defense responses in rice

    PubMed Central

    Hu, Lingfei; Ye, Meng; Li, Ran; Lou, Yonggen

    2016-01-01

    ABSTRACT WRKY proteins, which belong to a large family of plant-specific transcription factors, play important roles in plant defenses against pathogens and herbivores by regulating defense-related signaling pathways. Recently, a rice WRKY transcription factor OsWRKY53 has been reported to function as a negative feedback modulator of OsMPK3/OsMPK6 and thereby to control the size of the investment a rice plant makes to defend against a chewing herbivore, the striped stem borer Chilo suppressalis. We investigated the performance of a piecing-sucking herbivore, the brown planthopper (BPH) Nilaparvata lugens, on transgenic plants that silence or overexpress OsWRKY53, and found that OsWRKY53 activates rice defenses against BPH by activating an H2O2 burst and suppressing ethylene biosynthesis. These findings suggest that OsWRKY53 functions not only as a regulator of plants' investment in specific defenses, but also as a switch to initiate new defenses against other stresses, highlighting the versatility and importance of OsWRKY53 in herbivore-induced plant defenses. PMID:27031005

  13. OsWRKY53, a versatile switch in regulating herbivore-induced defense responses in rice.

    PubMed

    Hu, Lingfei; Ye, Meng; Li, Ran; Lou, Yonggen

    2016-04-01

    WRKY proteins, which belong to a large family of plant-specific transcription factors, play important roles in plant defenses against pathogens and herbivores by regulating defense-related signaling pathways. Recently, a rice WRKY transcription factor OsWRKY53 has been reported to function as a negative feedback modulator of OsMPK3/OsMPK6 and thereby to control the size of the investment a rice plant makes to defend against a chewing herbivore, the striped stem borer Chilo suppressalis. We investigated the performance of a piecing-sucking herbivore, the brown planthopper (BPH) Nilaparvata lugens, on transgenic plants that silence or overexpress OsWRKY53, and found that OsWRKY53 activates rice defenses against BPH by activating an H2O2 burst and suppressing ethylene biosynthesis. These findings suggest that OsWRKY53 functions not only as a regulator of plants' investment in specific defenses, but also as a switch to initiate new defenses against other stresses, highlighting the versatility and importance of OsWRKY53 in herbivore-induced plant defenses. PMID:27031005

  14. Role of rice cytosolic hexokinase OsHXK7 in sugar signaling and metabolism.

    PubMed

    Kim, Hyun-Bi; Cho, Jung-Il; Ryoo, Nayeon; Shin, Dong-Ho; Park, Youn-Il; Hwang, Yong-Sic; Lee, Sang-Kyu; An, Gynheung; Jeon, Jong-Seong

    2016-02-01

    We characterized the function of the rice cytosolic hexokinase OsHXK7 (Oryza sativa Hexokinase7), which is highly upregulated when seeds germinate under O2 -deficient conditions. According to transient expression assays that used the promoter:luciferase fusion construct, OsHXK7 enhanced the glucose (Glc)-dependent repression of a rice α-amylase gene (RAmy3D) in the mesophyll protoplasts of maize, but its catalytically inactive mutant alleles did not. Consistently, the expression of OsHXK7, but not its catalytically inactive alleles, complemented the Arabidopsis glucose insensitive2-1 (gin2-1) mutant, thereby resulting in the wild type characteristics of Glc-dependent repression, seedling development, and plant growth. Interestingly, OsHXK7-mediated Glc-dependent repression was abolished in the O2 -deficient mesophyll protoplasts of maize. This result provides compelling evidence that OsHXK7 functions in sugar signaling via a glycolysis-dependent manner under normal conditions, but its signaling role is suppressed when O2 is deficient. The germination of two null OsHXK7 mutants, oshxk7-1 and oshxk7-2, was affected by O2 deficiency, but overexpression enhanced germination in rice. This result suggests the distinct role that OsHXK7 plays in sugar metabolism and efficient germination by enforcing glycolysis-mediated fermentation in O2 -deficient rice. PMID:25951042

  15. Identifying Mantle Carbonatite Metasomatism through Os-Sr-Mg Isotopes in Tibetan Ultrapotassic Rocks

    NASA Astrophysics Data System (ADS)

    Liu, D.; Zhao, Z.; Zhu, D. C.; Niu, Y.; Widom, E.; Teng, F. Z.; DePaolo, D. J.

    2015-12-01

    Mantle-derived magmas at convergent plate boundaries provide unique insights into the nature of materials subducted to and recycled from depths. Here we present a study of Os-Sr-Mg isotopes on the Oligocene-Miocene ultrapotassic rocks aimed at better understanding geochemical evolution of mantle lithosphere beneath southern Tibet. Isotopic data confirm that ultrapotassic rocks in southern Tibet are of mantle origin, but underwent crustal contamination as evidenced by variably high 187Os/188Os that obviously deviates from normal mantle reservoir. Still some samples with mantle-like 187Os/188Os exhibit variably lower δ26Mg than mantle and crustal lithologies, suggesting that the isotopically light Mg may not be the result of crustal contamination but retain specific fingerprint of carbonate-related metasomatism in mantle sources. Mantle carbonatite metasomatism is also manifested by the inverse δ26Mg-87Sr/86Sr correlation, as well as the relative depletion of high field strength elements and the enrichment of CaO in ultrapotassic rocks. The positive co-variation between δ26Mg and Hf/Sm in low-187Os/188Os ultrapotassic rocks further highlights the potential of recycled dolomites to change mantle Mg isotopic compositions. The correlated spatial variations of δ26Mg and Hf/Sm indicate that the carbonatitic metasomatism during the northward subduction of the Neo-Tethyan slab may have laid the framework for generating postcollisional ultrapotassic rocks in southern Tibet.

  16. Identifying mantle carbonatite metasomatism through Os-Sr-Mg isotopes in Tibetan ultrapotassic rocks

    NASA Astrophysics Data System (ADS)

    Liu, Dong; Zhao, Zhidan; Zhu, Di-Cheng; Niu, Yaoling; Widom, Elisabeth; Teng, Fang-Zhen; DePaolo, Donald J.; Ke, Shan; Xu, Ji-Feng; Wang, Qing; Mo, Xuanxue

    2015-11-01

    Mantle-derived magmas at convergent plate boundaries provide unique insights into the nature of materials subducted to and recycled from depths. Here we present a study of Os-Sr-Mg isotopes on the Oligocene-Miocene ultrapotassic rocks aimed at better understanding sediment subduction and recycling beneath southern Tibet. New isotopic data confirm that ultrapotassic rocks in southern Tibet are of mantle origin, but underwent crustal contamination as evidenced by the variably high 187Os/188Os that obviously deviates from normal mantle reservoir. Still some samples with mantle-like 187Os/188Os exhibit δ26Mg significantly lower than mantle and crustal lithologies, suggesting that the isotopically light Mg may not result from crustal contamination but retain specific fingerprint of carbonate-related metasomatism in mantle sources. Mantle carbonatite metasomatism is manifested by the inverse δ26Mg-87Sr/86Sr correlations, as well as the depletion of high field strength elements relative to rare earth elements and the enrichment of CaO in ultrapotassic rocks. The positive co-variations between δ26Mg and Hf/Sm defined by those low-187Os/188Os ultrapotassic rocks provide evidence for the potential of recycled dolomites to modify mantle Mg isotopic composition. The correlated spatial variations of δ26Mg and Hf/Sm are interpreted to reflect carbonatitic metasomatism associated with the northward subduction of the Neo-Tethyan oceanic slab and its profound influence on postcollisional ultrapotassic magmatism.

  17. Characterization of the Grp94/OS-9 chaperone-lectin complex

    PubMed Central

    Seidler, Paul M.; Shinsky, Stephen A.; Hong, Feng; Li, Zihai; Cosgrove, Michael S.; Gewirth, Daniel T.

    2014-01-01

    Grp94 is a macromolecular chaperone belonging to the hsp90 family and is the most abundant glycoprotein in the endoplasmic reticulum of mammals. In addition to its essential role in protein folding, Grp94 was proposed to participate in the ER associated degradation (ERAD) quality control pathway by interacting with the lectin OS-9, a sensor for terminally misfolded proteins (TMPs). To understand how OS-9 interacts with ER chaperone proteins, we mapped its interaction with Grp94. Glycosylation of the full length Grp94 protein was essential for OS-9 binding, although deletion of the Grp94 N-terminal domain relieved this requirement suggesting that the effect was allosteric rather than direct. Although yeast OS-9 is composed of a well-established N-terminal MRH lectin domain and a C-terminal dimerization domain, we find that the C-terminal domain of OS-9 in higher eukaryotes contains ‘mammalian-specific insets’ that are specifically recognized by the middle and C-terminal domains of Grp94. Additionally, the Grp94 binding domain in OS-9 was found to be intrinsically disordered. The biochemical analysis of the interacting regions provides insight into the manner by which the two associate, and additionally hints at a plausible biological role for the Grp94/OS-9 complex. PMID:25193139

  18. Delayed development of os odontoideum after traumatic cervical injury: support for a vascular etiology.

    PubMed

    Zygourakis, Corinna C; Cahill, Kevin S; Proctor, Mark R

    2011-02-01

    A previously healthy 2-year-old girl sustained a C1-2 ligamentous injury after a motor vehicle accident and underwent successful halo immobilization, with postimmobilization images showing good cervical alignment. At the time, plain radiography, CT scanning, and MR imaging showed a normal odontoid. Four years later, however, the patient was found to have an os odontoideum, evident on plain radiography and CT imaging. At the 10-year follow-up, the os odontoideum had not been surgically repaired, and the child had mild hypermobility. This is the first documented case in the modern imaging era of delayed os odontoideum formation after definitive CT scanning showed no fracture. As such, this suggests that os odontoideum may result from traumatic vascular interruption in the developing spine, with resulting osseous remodeling leading to an os odontoideum. This case argues against the congenital etiology of os odontoideum, as well as the strict posttraumatic theory whereby a trauma-induced odontoid fracture leads to osseous remodeling and subsequent development of an os odontoideum. PMID:21284467

  19. OS-9 facilitates turnover of nonnative GRP94 marked by hyperglycosylation.

    PubMed

    Dersh, Devin; Jones, Stephanie M; Eletto, Davide; Christianson, John C; Argon, Yair

    2014-08-01

    The tight coupling of protein folding pathways with disposal mechanisms promotes the efficacy of protein production in the endoplasmic reticulum (ER). It has been hypothesized that the ER-resident molecular chaperone glucose-regulated protein 94 (GRP94) is part of this quality control coupling because it supports folding of select client proteins yet also robustly associates with the lectin osteosarcoma amplified 9 (OS-9), a component involved in ER-associated degradation (ERAD). To explore this possibility, we investigated potential functions for the GRP94/OS-9 complex in ER quality control. Unexpectedly, GRP94 does not collaborate with OS-9 in ERAD of misfolded substrates, nor is the chaperone required directly for OS-9 folding. Instead, OS-9 binds preferentially to a subpopulation of GRP94 that is hyperglycosylated on cryptic N-linked glycan acceptor sites. Hyperglycosylated GRP94 forms have nonnative conformations and are less active. As a result, these species are degraded much faster than the major, monoglycosylated form of GRP94 in an OS-9-mediated, ERAD-independent, lysosomal-like mechanism. This study therefore clarifies the role of the GRP94/OS-9 complex and describes a novel pathway by which glycosylation of cryptic acceptor sites influences the function and fate of an ER-resident chaperone. PMID:24899641

  20. 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.

  1. Re-Os geochemistry and geochronology of the Ransko gabbro-peridotite massif, Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Ackerman, Lukáš; Pašava, Jan; Erban, Vojtěch

    2013-10-01

    The Ransko gabbro-peridotite massif in Eastern Bohemia is a strongly differentiated intrusive complex, which hosts low-grade Ni-Cu ores mainly developed close to the contact of olivine-rich rocks with gabbros, in troctolites, and to a much lesser extent in both pyroxene and olivine gabbros and plagioclase-rich peridotites. Gabbro, troctolite, peridotite and Ni-Cu ores from the Jezírka Ni-Cu (PGE) deposit, considered to be a typical example of the liquid segregation style of mineralization, were analyzed for Re-Os concentrations and isotopic ratios. Seven barren and mineralized samples from the Jezírka deposit yielded a Re-Os regression of 341.5 ± 7.9 Ma (MSWD = 69). Strongly mineralized peridotite with mantle-like initial 187Os/188Os ratio of 0.125 suggests that Os as well as other PGE present in the Ni-Cu mineralization are predominantly of mantle origin. On the other hand, barren and low-mineralized samples have radiogenic initial 187Os/188Os ratios of 0.14-0.16 suggesting some import of Re and/or radiogenic 187Os most likely through contamination by continental crust during magma emplacement. The Re-Os age of the Ransko Massif is significantly younger than the previously suggested Lower Cambrian age, but it is similar to and/or younger than the age of metamorphism of the adjacent Kutná Hora crystalline complex and the Moldanubian unit. Therefore, it is likely that the emplacement of the Ransko massif and its Ni-Cu mineralization was closely connected with the late-stage evolution of the Kutná Hora crystalline complex.

  2. Fractionation of Highly Siderophile Elements in Refertilized Mantle: Implications for the Os Isotope Composition of Basalts

    NASA Astrophysics Data System (ADS)

    Marchesi, C.; Dale, C. W.; Garrido, C. J.; Pearson, D. G.; Bosch, D.; Bodinier, J. L.; Gervilla, F.; Hidas, K.

    2014-12-01

    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. Modelling 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.

  3. 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.

  4. 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. PMID:27345872

  5. The rice monovalent cation transporter OsHKT2;4: revisited ionic selectivity.

    PubMed

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

    2012-09-01

    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 Ca(2+) when expressed in Xenopus oocytes. Here, OsHKT2;4 functional properties were reassessed in Xenopus oocytes. A Ca(2+) 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 Ca(2+) conditions and lack of sensitivity of OsHKT2;4 zero-current potential and conductance to external Ca(2+). The Ca(2+) 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(+) ≈ NH(4)(+)). 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

  6. 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

  7. 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.

  8. Plume impingement on the Siberian SCLM: Evidence from Re-Os isotope systematics

    NASA Astrophysics Data System (ADS)

    Pernet-Fisher, J. F.; Howarth, G. H.; Pearson, D. G.; Woodland, S.; Barry, P. H.; Pokhilenko, N. P.; Pokhilenko, L. N.; Agashev, A. M.; Taylor, L. A.

    2015-03-01

    We report Re-Os and platinum group element (PGE) systematics for a suite of 16 mantle peridotites from the Udachnaya (360 Ma) and Obnazhennaya (160 Ma) kimberlite pipes, Siberia. Xenoliths from these pipes bracket the thermal climax of the Siberian plume, which is represented by the emplacement of the ~ 250 Ma Siberian Flood Basalts (SFBs). Thus, these xenoliths represent snapshots of the sub-continental lithospheric mantle (SCLM) before and after plume modification. Pre-plume Udachnaya peridotite xenoliths generally display unradiogenic Os-isotopes with respect to CI-chondrite (expressed by γOs, the percentage difference between the Os-isotope composition of a sample and the average chondrite composition; 187Os/188Os - 0.127), coupled with low [Pd/Ir]N, for both whole-rock and olivine mineral-fraction analyses. Such signatures are typical of an ancient depleted cratonic mantle that underwent melt extraction. The preservation of unradiogenic Os-isotope compositions (γOs - 5 to - 14), coupled with low (< 0.4) 187Re/188Os ratios, provides robust melt extraction age estimates, ranging from ~ 3 Ga to ~ 1.2 Ga. This indicates that craton stabilization/growth events not only occurred during the Archean, but also extended into the Proterozoic. A number (4) of post-plume Obnazhennaya peridotites display 187Os/188Os ratios (> 0.1292), which overlap the convecting mantle range. At first glance, these observations are in agreement with garnet chemistry data, which indicate that high-degrees of silicate-melt percolated through the lithosphere during the emplacement of the SFB. However, Obnazhennaya olivine mineral-separates display 'depleted' systematics (> Fo 92 and low [Pd/Ir]N), consistent with 'pristine' melt residues. We suggest that these Obnazhennaya xenoliths represent 'newly formed' residues associated with partial melts extracted from the impinging Siberian plume on the SCLM. During plume impingement, thermo-chemical erosion of the lithosphere is thought to be an

  9. 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. PMID:26732823

  10. 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

  11. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  12. 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.

  13. 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

  14. OsKAT2 is the prevailing functional inward rectifier potassium channels in rice guard cell

    PubMed Central

    Hwang, Hyunsik; Yoon, Jin-Young; Cho, Hana; Kim, Beom-Gi

    2013-01-01

    AtKAT1 plays roles as a major channel to uptake K+ in guard cell when stomata open in dicot model plant Arabidopsis. In a recent publication, we isolated 3 KAT-like potassium channels in rice. We expressed them in CHO cell to identify electrophysiological characteristics of the channels. OsKAT2 showed much bigger inwardly rectifying potassium channel activities among them. The histochemical X-glu staining of transgenic rice leaf blades expressing β-glucuronidase fused with OsKAT2 promoter showed that the OsKAT2 is dominantly expressed in rice guard cell. These findings indicate that OsKAT2 may be a functional ortholog of AtKAT1 in rice. Thus this gene will be the prime target for engineering the guard cell movement to improve drought tolerance in monocot plants, including most major crops. PMID:24103920

  15. 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.

  16. 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

  17. Regulatory role of the OsWOX3A transcription factor in rice root development.

    PubMed

    Cho, Sung-Hwan; Paek, Nam-Chon

    2016-06-01

    WUSCHEL-related homeobox (WOX) transcription factors play important roles in cell fate determination during plant development and function in the signaling pathways of phytohormones such as gibberellic acid (GA). In a recent study, we demonstrated that OsWOX3A directly binds to the promoter of the KAO gene, which encodes ent-kaurenoic acid oxidase, an enzyme involved in GA biosynthesis, and represses KAO expression. Interestingly, we observed that OsWOX3A overexpression causes not only severe dwarfism, but also an increase in the number of lateral roots. Moreover, the expression of PIN-FORMED 1 (PIN1), involved in polar auxin transport, is significantly upregulated in OsWOX3A-OX plants. These findings indicate that OsWOX3A may be involved in modulation of GA-auxin crosstalk in rice root development. PMID:27171233

  18. 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

  19. Extensive set of macros for structured programing in OS/360 assembly language (STRCMACS)

    NASA Technical Reports Server (NTRS)

    Barth, C. W.

    1975-01-01

    Development of consistent assembly language structured programming techniques has been enhanced by use of assembly macros developed for structured programing. Set of macros was written for IBM OS/360 Assembly language.

  20. Pressure induced structural phase transition of OsB 2: First-principles calculations

    NASA Astrophysics Data System (ADS)

    Ren, Fengzhu; Wang, Yuanxu; Lo, V. C.

    2010-04-01

    Orthorhombic OsB 2 was synthesized at 1000 °C and its compressibility was measured by using the high-pressure X-ray diffraction in a Diacell diamond anvil cell from ambient pressure to 32 GPa [R.W. Cumberland, et al. (2005)]. First-principles calculations were performed to study the possibility of the phase transition of OsB 2. An analysis of the calculated enthalpy shows that orthorhombic OsB 2 can transfer to the hexagonal phase at 10.8 GPa. The calculated results with the quasi-harmonic approximation indicate that this phase transition pressure is little affected by the thermal effect. The calculated phonon band structure shows that the hexagonal P 6 3/ mmc structure (high-pressure phase) is stable for OsB 2. We expect the phase transition can be further confirmed by the experimental work.

  1. 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…

  2. 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.

  3. 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

  4. 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

  5. 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

    NASA Astrophysics Data System (ADS)

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

    2014-08-01

    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,b; 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 are mimicking the natural system. This

  6. Tri-axial Shape Coexistence and a New Aligned Band in 178Os

    NASA Astrophysics Data System (ADS)

    Govil, I. M.

    2009-03-01

    The Os nuclei lie in the beginning of the transitional region between the well deformed rare earth and spherical lead isotopes. The nuclei in this region are believed to be soft to changes in gamma deformation due to the softness of nuclear potential which may result in the shape coexistence. The neutron Fermi levels in Os nuclei from A = 170 to A = 186 lie in the middle of i13/2 orbital so that their shape in the ground state tends to take an appreciable prolate deformation. Hence collective bands with the well defined moment of inertia occur and the effect of different proton orbitals is observed as a modulation of the prolate structure. The anomalies in the yrast sequence, an effect attributed to change in moment of inertia of the ground state rotational band and the band crossing phenomena, are very important and vary strongly with neutron number in case of Os nuclei. The nuclear structure of 178Os nucleus has been studied using the reaction 165Ho (20Ne, p6n) 178Os. Indian National Gamma Array (INGA) consisting of six Clover detectors with anti Compton shields was used for the detection of resulting gamma rays. The Direction Correlation of γ-rays de-exciting Oriented states (DCO) ratio and polarization of gamma rays were measured to assign spin, parity and multipolarity of transitions. Twenty one new transitions belonging to the 178Os nucleus have been identified. The sudden and rather strong gain in aligned angular momentum is observed in the yrast band of 178Os. A new aligned rotational band similar to 180Os is also discovered in this nucleus. This band exhibits a very complex decay pattern with a single linking transition of 1778 keV to the ground state band. The tri-axial shape co-existence is also observed in this nucleus at higher excitation. The experimental results are compared with the Microscopic Hartree-Fock model calculations.

  7. 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.

  8. Functional analysis of the rice vacuolar zinc transporter OsMTP1

    PubMed Central

    Menguer, Paloma K.; Farthing, Emily; Peaston, Kerry A.; Ricachenevsky, Felipe Klein; Fett, Janette Palma; Williams, Lorraine E.

    2013-01-01

    Heavy metal homeostasis is maintained in plant cells by specialized transporters which compartmentalize or efflux metal ions, maintaining cytosolic concentrations within a narrow range. OsMTP1 is a member of the cation diffusion facilitator (CDF)/metal tolerance protein (MTP) family of metal cation transporters in Oryza sativa, which is closely related to Arabidopsis thaliana MTP1. Functional complementation of the Arabidopsis T-DNA insertion mutant mtp1-1 demonstrates that OsMTP1 transports Zn in planta and localizes at the tonoplast. When heterologously expressed in the yeast mutant zrc1 cot1, OsMTP1 complemented its Zn hypersensitivity and was also localized to the vacuole. OsMTP1 alleviated, to some extent, the Co sensitivity of this mutant, rescued the Fe hypersensitivity of the ccc1 mutant at low Fe concentrations, and restored growth of the Cd-hypersensitive mutant ycf1 at low Cd concentrations. These results suggest that OsMTP1 transports Zn but also Co, Fe, and Cd, possibly with lower affinity. Site-directed mutagenesis studies revealed two substitutions in OsMTP1 that alter the transport function of this protein. OsMTP1 harbouring a substitution of Leu82 to a phenylalanine can still transport low levels of Zn, with an enhanced affinity for Fe and Co, and a gain of function for Mn. A substitution of His90 with an aspartic acid completely abolishes Zn transport but improves Fe transport in OsMTP1. These amino acid residues are important in determining substrate specificity and may be a starting point for refining transporter activity in possible biotechnological applications, such as biofortification and phytoremediation. PMID:23761487

  9. Functional characterization of a type 2 metallothionein isoform (OsMTI-2b) from rice.

    PubMed

    Pirzadeh, Soheil; Shahpiri, Azar

    2016-07-01

    Metallothioneins (MTs) are a family of Cys-rich, low molecular weight, cytoplasmic metal binding proteins. MTs are present in all eukaryotes as well as some prokaryotes. Plant MTs are divided into four types based on Cys distribution pattern in their amino acid sequences. In the present work, the gene encoding OsMTI-2b, a type 2 MT found in rice, was cloned into pET41a vector. The resulting construct was transformed into Escherichia coli strain Rosetta (DE3). Following the induction with Isopropyl β-d-1-thiogalactopyranoside the OsMTI-2b was expressed as carboxyl-terminal extensions of glutathione-S-transferase (GST-tag), a 6His-tag, and an S-tag. The expressed recombinant fusion protein was named GST-OsMTI-2b. As compared with control, transgenic E. coli cells expressing GST-OsMTI-2b accumulated more Pb(2+), Ni(2+), Cd(2+), Zn(2+) and Cu(2+) from culture medium and showed increased tolerance against these metals. Furthermore the E. coli cells expressing OsMTI-2b accumulated significantly higher Pb(2+) than previously made strains which expressing other rice OsMT isoforms. The recombinant GST-OsMTI-2b was purified using affinity chromatography. According to in vitro assays the protein GST-OsMTI-2b was able to form complexes with Pb(2+), Ni(2+), Cd(2+) and Zn(2+). However, the binding ability for the different metals differed in the order: Pb(2+)>Cd(2+)>Zn(2+)>Ni(2+). PMID:27079330

  10. X-ray microanalysis of aldehyde-fixed glycogen contrast-stained by OsVI . FeII and OsVI . RuIV complexes.

    PubMed

    de Bruijn, W C; van Buitenen, J M

    1980-11-01

    The composition of the contrast-donating complex of rat liver glycogen, nucleoplasm, erythrocytes, and mitochondria was established by X-ray microanalysis. In these compartments the presence of osmium and iron was shown qualitatively in tissue after glutaraldehyde fixation, treated with OsVIIIO4 plus K4FeII(CN)6 and in similar tissue treated with a combination of K2OsVIO4 plus K4FeII(CN)6. Osmium and ruthenium were detected in these compartments, in aldehyde-fixed tissue treated with mixtures containing K2RuIVL(CN)6 rather than K4FeII(CN)6. The iron detected in the glycogen, nucleoplasm, erythrocytes, and mitochondria of tissue treated with K2RuIV(CN)6 mixtures proved to derive from sources inside the electron microscope, and had to be considered an artifact. Quantitatively, the mean atomic ratios of osmium-to-iron and osmium-to-ruthenium were determined from spectra obtained by point analyses of the same compartments (glycogen, nucleoplasm, mitochondria, lipid droplets, and erythrocytes). After correction of the spectra for the instrumental iron contribution, the osmium-to-iron and osmium-to-ruthenium ratios in the glycogen were about 1:3 for tissue treated with those combinations including K2OsVIO4. In the other compartments, the osmium-to-iron and osmium-to-ruthenium ratios were virtually 1:0. For Os-VIIIO4 in combination with potassium ferrouscyanide however the osmium-to-iron ratio was 1:7 in the glycogen and 1:5 in all other compartments. OsVIIIO4 was combined with potassium ruthenium-cyanide, the osmium-to-ruthenium ratio was 1:2 in the glycogen and 2:1 in the other compartments. These results support our view that the selective glycogen contrast is obtained by complex formation. PMID:6159393

  11. Surgical treatment of os acromiale with and without associated rotator cuff tears.

    PubMed

    Abboud, Joseph A; Silverberg, David; Pepe, Mathew; Beredjiklian, Pedro K; Iannotti, Joseph P; Williams, Gerald R; Ramsey, Matthew L

    2006-01-01

    Nineteen consecutive patients treated surgically for meso-os acromiale and subacromial pathology were reviewed retrospectively, with a mean length of follow-up of 40 months (range, 24-94 months). Of the patients, 11 (58%) were treated with acromioplasty in the presence of a stable os acromiale; 8 patients (42%) underwent open reduction-internal fixation for an unstable and painful os fragment. Of the 19 patients, 8 (42%) with an os acromiale had an associated full-thickness rotator cuff tear. Overall, only 10 of 19 patients (53%) achieved a satisfactory result. All 8 patients (100%) treated with open reduction-internal fixation achieved union of the os fragment, although only 3 (37.5%) achieved a satisfactory result. Of the 11 patients who underwent acromioplasty, only 7 (64%) achieved a satisfactory result. The outcome of surgical management of symptomatic meso-os acromiale with concomitant rotator cuff pathology was satisfactory in 4 of 8 patients in our study group. The rate of satisfactory results was similar in patients with (50%) and without (55%) associated rotator cuff tears. When we analyzed our results to exclude workers' compensation patients, 80% achieved satisfactory results (compared with only 22% in our workers' compensation group). PMID:16679224

  12. The BiCu1-xOS oxysulfide: Copper deficiency and electronic properties

    NASA Astrophysics Data System (ADS)

    Berthebaud, D.; Guilmeau, E.; Lebedev, O. I.; Maignan, A.; Gamon, J.; Barboux, P.

    2016-05-01

    An oxysulfide series of nominal compositions BiCu1-xOS with x<0.20 has been prepared and its structural properties characterized by combining powder X-ray diffraction and transmission electron microscopy techniques. It is found that this oxysulfide, crystallizing in the P4/nmm space group, tends to adopt a constant amount of copper vacancy corresponding to x=0.05 in the BiCu1-xOS formula. The presence of Cu vacancies is confirmed by HAADF-STEM analysis showing, in the Cu atomic columns, alternating peaks of different intensities in some very localized regions. For larger Cu deficiencies (x>0.05 in the nominal composition), other types of structural nanodefects are evidenced such as bismuth oxysulfides of the "BiOS" ternary system which might explain the report of superconductivity for the BiCu1-xOS oxysulfide. Local epitaxial growth of the BiCuOS oxysulfide on top of CuO is also observed. In marked contrast to the BiCu1-xOSe oxyselenide, these results give an explanation to the limited impact of Cu deficiency on the Seebeck coefficient in BiCu1-xOS compounds.

  13. 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.

  14. 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

  15. Molecular Mechanism for Fungal Cell Wall Recognition by Rice Chitin Receptor OsCEBiP.

    PubMed

    Liu, Simiao; Wang, Jizong; Han, Zhifu; Gong, Xinqi; Zhang, Heqiao; Chai, Jijie

    2016-07-01

    Chitin is the major component of fungal cell wall and serves as a molecular pattern that can be recognized by the receptor OsCEBiP in rice, a lysine motif (LysM) receptor-like protein (RLP), to trigger immune responses. The molecular mechanisms underlying chitin recognition remain elusive. Here we report the crystal structures of the ectodomain of OsCEBiP (OsCEBiP-ECD) in free and chitin-bound forms. The structures reveal that OsCEBiP-ECD contains three tandem LysMs followed by a novel structure fold of cysteine-rich domain. The structures showed that chitin binding induces no striking conformational changes in OsCEBiP. Structural comparison among N-acetylglucosamine (NAG) oligomer-bound LysMs revealed a highly conserved recognition mechanism, which is expected to facilitate study of other LysM-containing proteins for their NAG binding. Modeling study showed that chitin induces OsCEBiP homodimerization in a "sliding mode". Our data provide insights into rice chitin receptor-mediated immunity triggered by fungal cell wall. PMID:27238968

  16. Disruption of OsYSL15 leads to iron inefficiency in rice plants.

    PubMed

    Lee, Sichul; Chiecko, Jeff C; Kim, Sun A; Walker, Elsbeth L; Lee, Youngsook; Guerinot, Mary Lou; An, Gynheung

    2009-06-01

    Uptake and translocation of metal nutrients are essential processes for plant growth. Graminaceous species release phytosiderophores that bind to Fe(3+); these complexes are then transported across the plasma membrane. We have characterized OsYSL15, one of the rice (Oryza sativa) YS1-like (YSL) genes that are strongly induced by iron (Fe) deficiency. The OsYSL15 promoter fusion to beta-glucuronidase showed that it was expressed in all root tissues when Fe was limited. In low-Fe leaves, the promoter became active in all tissues except epidermal cells. This activity was also detected in flowers and seeds. The OsYSL15:green fluorescent protein fusion was localized to the plasma membrane. OsYSL15 functionally complemented yeast strains defective in Fe uptake on media containing Fe(3+)-deoxymugineic acid and Fe(2+)-nicotianamine. Two insertional osysl15 mutants exhibited chlorotic phenotypes under Fe deficiency and had reduced Fe concentrations in their shoots, roots, and seeds. Nitric oxide treatment reversed this chlorosis under Fe-limiting conditions. Overexpression of OsYSL15 increased the Fe concentration in leaves and seeds from transgenic plants. Altogether, these results demonstrate roles for OsYSL15 in Fe uptake and distribution in rice plants. PMID:19376836

  17. 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

  18. Solid Metal-Liquid Metal Partitioning of Pt, Re, and Os: The Effect of Carbon

    NASA Technical Reports Server (NTRS)

    Chabot, N. L.; Campbell, A. J.; Humayun, M.

    2004-01-01

    If the measured Os isotopic ratios are a signature from the Earth's outer core, understanding them is a unique opportunity to understand more about the Earth's core. The distribution of elements between the Earth's solid inner core and the liquid outer core will depend on their solid metal-liquid metal partition coefficients (D). Solid metal-liquid metal partitioning data are loosely consistent with the needed fractionations between Re-Os and Pt-Os to account for the Os isotopic signature; D(Os) is greater than both D(Re) and D(Pt), and the magnitude of the partition coefficients are similar to those needed [e.g. 7, 8]. The pressure in the core, the composition of the core, and the crystal structure of the solid Fe alloy in the inner core may influence the specific values of the partition coefficients. It may thus be possible to use these sensitivities of the partition coefficients to gain insight into the conditions within the Earth's core. In this abstract, we focus on the compositional influence of C, a potential component of the light element in the Earth's core [9], on the partitioning behaviors of Pt, Re, and Os.

  19. Preparation and characterization of carbon-supported PtOs electrocatalysts via polyol reduction method for methanol oxidation reaction

    NASA Astrophysics Data System (ADS)

    Li, Zuopeng; Li, Muwu; Han, Mingjia; Zeng, Jianhuang; Li, Yuexia; Guo, Yanqin; Liao, Shijun

    2014-12-01

    A polyol reduction approach was employed to prepare carbon-supported PtOs/C electrocatalysts (PtOs-1/C was obtained via the co-reduction of H2PtCl6 and K2OsCl6 precursors and PtOs-2/C was obtained via a sequential deposition method in which Pt was deposited on the preformed Os nanoparticles). The home-made electrocatalysts were extensively characterized via transmission electron microscopy, thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. The evaluation results of the catalytic activities obtained via cyclic voltammetry, CO stripping voltammetry, and chronoamperometry showed that the successively reduced PtOs-2/C out-performed PtOs-1/C in terms of specific/mass activity (528 mA mg-1PtOs and 0.98 mA cm-2) and CO tolerance in room temperature methanol electrooxidation reaction. The physical characteristics of the electrocatalysts correlated well with their electrochemical performances. The higher activity of PtOs-2/C was attributed to a combination of factors, such as a mix of nanoparticles (isolated Os, PtOs alloys or bimetallic nanoparticles), higher metallic Os content, and smaller particle sizes.

  20. 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...

  1. 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... and noncombatant training and service in the Armed Forces shall be classified in Class 1-O-S...

  2. Expression of a gene encoding a rice RING zinc-finger protein, OsRZFP34, enhances stomata opening.

    PubMed

    Hsu, Kuo-Hsuan; Liu, Chia-Chin; Wu, Shaw-Jye; Kuo, Ying-Yu; Lu, Chung-An; Wu, Ching-Rong; Lian, Pei-Jyun; Hong, Chwan-Yang; Ke, Yi-Ting; Huang, Juin-Hua; Yeh, Ching-Hui

    2014-09-01

    By oligo microarray expression profiling, we identified a rice RING zinc-finger protein (RZFP), OsRZFP34, whose gene expression increased with high temperature or abscisic acid (ABA) treatment. As compared with the wild type, rice and Arabidopsis with OsRZFP34 overexpression showed increased relative stomata opening even with ABA treatment. Furthermore, loss-of-function mutation of OsRZFP34 and AtRZFP34 (At5g22920), an OsRZFP34 homolog in Arabidopsis, decreased relative stomata aperture under nonstress control conditions. Expressing OsRZFP34 in atrzfp34 reverted the mutant phenotype to normal, which indicates a conserved molecular function between OsRZFP34 and AtRZFP34. Analysis of water loss and leaf temperature under stress conditions revealed a higher evaporation rate and cooling effect in OsRZFP34-overexpressing Arabidopsis and rice than the wild type, atrzfp34 and osrzfp34. Thus, stomata opening, enhanced leaf cooling, and ABA insensitivity was conserved with OsRZFP34 expression. Transcription profiling of transgenic rice overexpressing OsRZFP34 revealed many genes involved in OsRZFP34-mediated stomatal movement. Several genes upregulated or downregulated in OsRZFP34-overexpressing plants were previously implicated in Ca(2+) sensing, K(+) regulator, and ABA response. We suggest that OsRZFP34 may modulate these genes to control stomata opening. PMID:25002225

  3. 32 CFR 1630.17 - Class 1-O-S: Conscientious objector to all military service (separated).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 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...

  4. 32 CFR 1630.17 - Class 1-O-S: Conscientious objector to all military service (separated).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 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...

  5. 32 CFR 1630.17 - Class 1-O-S: Conscientious objector to all military service (separated).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 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...

  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. Re Os isotopic systematics of the Voisey's Bay Ni Cu Co magmatic ore system, Labrador, Canada

    NASA Astrophysics Data System (ADS)

    Lambert, D. D.; Foster, J. G.; Frick, L. R.; Li, C.; Naldrett, A. J.

    1999-06-01

    Re and Os concentrations and Os isotopic compositions have been obtained for massive, matrix, and disseminated sulphide ores from three environments within the Voisey's Bay intrusion (the `Ovoid', Eastern Deeps, and Discovery Hill Zone) in order to assess the role of crustal contamination in the genesis of this large Cu-Ni-Co deposit. These samples have high Re concentrations (148 to 288 ppb, in 100% sulphide) for their common Os concentrations (4.8 to 24 ppb, in 100% sulphide), yielding high Re/Os ratios (12 to 33). These data confirm that the magma parental to the Voisey's Bay ore system was broadly basaltic in major element chemistry rather than picritic, consistent with the low Ni/Cu ratio of the ores (˜1.5). Re-Os isotopic data exhibit a limited spread in 187Re/ 188Os (57 to 157) and define an imprecise 1323±135 Ma `model 3' isochron, likely the result of small R-factor variations within the ore system. The Re-Os isochron age is within error of 1334 Ma U-Pb ages obtained for baddeleyite from the ore-bearing troctolites, demonstrating that whole rock Re-Os isotopic systematics have remained closed since crystallisation. The initial Os isotopic composition of the isochron ( γOs=1040±200) implies significant magma interactions with radiogenic Os that most likely resides in the Nain-Churchill Province crust. These data are, therefore, consistent with the parental magma achieving sulphide saturation as a result of contamination by radiogenic crustal components, with further addition of base and precious metals as a function of R-factor. Analyses of sulphide separates from the Proterozoic Tasiuyak (Churchill) and Archaean Nain gneisses confirm that both units contained significant Os (8.6 ppb and 0.38 ppb, respectively) that was very radiogenic at 1334 Ma ( γOs=1908 and 5202, respectively), yielding crustal residence TCHUR model ages of 2200 to 2400 Ma. However, these model ages may have been affected by Re and/or Os mobility during the 1.85 Ga Torngat and 1

  8. Tissue-specific expression, developmentally and spatially regulated alternative splicing, and protein subcellular localization of OsLpa rice.

    PubMed

    Lu, Hai-ping; Pang, Wei-qin; Li, Wen-xu; Tan, Yuan-yuan; Wang, Qing; Zhao, Hai-jun; Shu, Qing-yao

    2016-02-01

    The OsLpa1 gene (LOC_Os57400) was identified to be involved in phytic acid (PA) metabolism because its knockout and missense mutants reduce PA content in rice grain. However, little is known about the molecular characteristics of OsLpa rice and of its homologues in other plants. In the present study, the spatial pattern of OsLpa1 expression was revealed using OsLpa1 promoter::GUS transgenic plants (GUS: β-glucuronidase); GUS histochemical assay showed that OsLpa1 was strongly expressed in stem, leaf, and root tissues, but in floral organ it is expressed mainly and strongly in filaments. In seeds, GUS staining was concentrated in the aleurone layers; a few blue spots were observed in the outer layers of embryo, but no staining was observed in the endosperm. Three OsLpa1 transcripts (OsLpa1.1, OsLpa1.2, OsLpa1.3) are produced due to alternative splicing; quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis revealed that the abundance of OsLpa1.3 was negligible compared with OsLpa1.1 and OsLpa all tissues. OsLpa1.2 is predominant in germinating seeds (about 5 times that of OsLpa1.1), but its abundance decreases quickly with the development of seedlings and plants, whereas the abundance of OsLpa1.1 rises and falls, reaching its highest level in 45-d-old plants, with abundance greater than that of OsLpa both leaves and roots. In seeds, the abundance of OsLpa1 continuously increases with seed growth, being 27.5 and 15 times greater in 28-DAF (day after flowering) seeds than in 7-DAF seeds for OsLpa1.1 and OsLpa1.2, respectively. Transient expression of chimeric genes with green fluorescence protein (GFP) in rice protoplasts demonstrated that all proteins encoded by the three OsLpa1 transcripts are localized to the chloroplast. PMID:26834011

  9. Meteorite - Impact Melt Mixing: PGE and Re-Os Evidence from the Morokweng Impact, South Africa

    NASA Astrophysics Data System (ADS)

    Hart, R.; Andreoli, M.; Cloete, M.; McDonald, I.; Carlson, R. W.; Tredoux, M.

    2001-12-01

    Preserved within the 870m thick impact melt sheet of the 144 Ma Morokweng impact structure, South Africa (1,2) are small (mm-cm) inclusions that are interpreted to be remnants of the impactor. Inclusions are disseminated throughout the melt sheet and consist of ultramafic silicate clasts with segregations of Ni-rich sulfides and oxides. The silicate component in the inclusions displays remnant fabric and, where unaltered, has mineral compositions consistent with ordinary chondrites (3). The sulfide-oxide component of the inclusions is Ni-rich, has high PGE contents (Ir = 16.7 x chondrite) and fractionated PGE ratios compared to chondrites and to the bulk impact melt which reflects the signature of the ordinary chondrite impactor (4). Specifically, the oxides show depletion in Pd, while the sulfide is slightly enriched in Rh and Pt and strongly enriched in Pd relative to Ir and Ru. Significantly, Ru and Ir (the high temperature PGE's) are not fractionated from one another. Initial Os isotopic compositions of the inclusion sulfides and oxides (0.1335 - 0.1358) are slightly more radiogenic than found in the melt rock (0.1301 - 0.1324), but both are substantially less radiogenic than a sample of the basement granite (0.259). The 1/Os vs 187Os/188Os correlation displayed by the bulk melt rocks is consistent with the presence of 1-3 wt% chondritic impactor in the crustal melt. The more radiogenic Os found in the inclusion minerals indicates that the inclusions contain a larger crustal PGE component than the melt rock. Though Os concentration is well correlated with Os isotopic composition in the melt rock, Re concentration is not. Thus, simple binary mixing between crustal melt and meteorite cannot explain the Re-Os systematics. The Re-Os and PGE fractionation observed in inclusion minerals suggests that meteorite-impact melt mixing occurred first through chemical exchange between oxidized melt and reduced, metal or sulfur-rich, impactor. Lithophile elements (e.g. Fe

  10. 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.

  11. Knock-down of OsDCL2 in rice negatively affects maintenance of the endogenous dsRNA virus, Oryza sativa endornavirus.

    PubMed

    Urayama, Syunichi; Moriyama, Hiromitsu; Aoki, Nanako; Nakazawa, Yukihiro; Okada, Ryo; Kiyota, Eri; Miki, Daisuke; Shimamoto, Ko; Fukuhara, Toshiyuki

    2010-01-01

    An endogenous double-stranded RNA (dsRNA), which has recently been recognized as the dsRNA virus Oryza sativa endornavirus (OsEV), is found in many strains of cultivated rice (Oryza sativa). Small RNAs derived from OsEV dsRNA were detected, indicating that the RNA silencing machinery recognizes OsEV dsRNA. The existence of OsEV in knock-down (KD) lines of five genes of RNA-dependent RNA polymerase (OsRDR1-OsRDR5) or two genes of Dicer-like protein (OsDCL2 or OsDCL3a) was examined to characterize the relationship between the host RNA silencing system and the propagation of this dsRNA virus. OsEV was not detected in OsRDR4-KD or OsDCL2-KD T(1) lines. We attempted to introduce OsEV into these KD lines by crossing them with OsEV-carrying plants because of the efficient transmission of OsEV to F(1) plants via pollen or ova. All OsRDR4-KD but only some OsDCL2-KD F(1) plants contained OsEV. Some OsDCL2-KD F(1) plants consisted of OsEV-carrying and OsEV-free cells. These results suggest that the maintenance of OsEV is unstable in OsDCL2-KD plants. Furthermore, the amount of OsEV-derived small interfering RNA (vsiRNA) in the OsDCL2-KD plants increased relative to the wild type. This increased level of vsiRNA may cause OsEV instability during cell division. PMID:19933266

  12. Laser studies of radiationless decay mechanisms in Os/sup 2 +///sup 3 +/ polypyridine complexes

    SciTech Connect

    Netzel, T.L.; Bergkamp, M.A.

    1982-01-01

    The lowest energy excited states in Os(II) polypyridine complexes are of a metal-to-ligand charge transfer (MLCT) type and live for 10 to 40 ..mu..s at 4.2/sup 0/K. The long wavelength absorptions in the visible region of the spectrum in Os(III) polypyridine complexes arise from ligand-to-metal charge transfer (LMCT) transitions and do not produce detectable luminescence. This suggests that these LMCT states are very short lived. Results of picosecond absorption studies on the lifetimes the LMCT states in OsL/sub 3//sup 3 +/ complexes (L = 2,2'-bipyridine(bpy) or 1,10-phenanthroline(phen)) as functions of temperature and isotopic substitution are reported. The LMCT lifetimes at low temperature are contrasted with the low temperature lifetimes of the MLCT states of OsL/sub 3//sup 2 +/ complexes and both are examined from the perspective of a coarse-grained radiationless decay theory developed by Englman, R. and Jortner, J. (Molec. Phys. 1970, 18, 145). The agreement between experiment and theory suggests the following: (1) Englman and Jortner's theory of radiationless decay is useful for inorganic as well as organic systems; (2) mid-frequency (1300 to 1600 cm/sup -1/) vibrations are the important energy accepting modes for radiationless decay of the charge transfer excited states of OsL/sub 3//sup 2 +///sup 3 +/ complexes and; (3) the 10/sup 5/-10/sup 6/ difference in lifetimes between the MLCT states of OsL/sub 3//sup 2 +/ complexes and the LMCT states of OsL/sub 3//sup 3 +/ complexes is largely due to the difference in their energy gaps.

  13. Homeobox Is Pivotal for OsWUS Controlling Tiller Development and Female Fertility in Rice.

    PubMed

    Mjomba, Fredrick Mwamburi; Zheng, Yan; Liu, Huaqing; Tang, Weiqi; Hong, Zonglie; Wang, Feng; Wu, Weiren

    2016-01-01

    OsWUS has recently been shown to be a transcription factor gene critical for tiller development and fertility in rice. The OsWUS protein consists of three conserved structural domains, but their biological functions are still unclear. We discovered a new rice mutant resulting from tissue culture, which hardly produced tillers and exhibited complete female sterility. The male and female floral organs of the mutant were morphologically indistinguishable from those of the wild type. We named the mutant srt1 for completely sterile and reduced tillering 1. Map-based cloning revealed that the mutant phenotypes were caused by a mutation in OsWUS Compared with the two previously reported null allelic mutants of OsWUS (tab1-1 and moc3-1), which could produce partial N-terminal peptides of OsWUS, the srt1 protein contained a deletion of only seven amino acids within the conserved homeobox domain of OsWUS. However, the mutant phenotypes (monoculm and female sterility) displayed in srt1 were as typical and severe as those in tab1-1 and moc3-1 This indicates that the homeobox domain of SRT1 is essential for the regulation of tillering and sterility in rice. In addition, srt1 showed an opposite effect on panicle development to that of the two null allelic mutants, implying that the srt1 protein might still have partial or even new functions on panicle development. The results of this study suggest that the homeobox domain is pivotal for OsWUS function. PMID:27194802

  14. Homeobox Is Pivotal for OsWUS Controlling Tiller Development and Female Fertility in Rice

    PubMed Central

    Mjomba, Fredrick Mwamburi; Zheng, Yan; Liu, Huaqing; Tang, Weiqi; Hong, Zonglie; Wang, Feng; Wu, Weiren

    2016-01-01

    OsWUS has recently been shown to be a transcription factor gene critical for tiller development and fertility in rice. The OsWUS protein consists of three conserved structural domains, but their biological functions are still unclear. We discovered a new rice mutant resulting from tissue culture, which hardly produced tillers and exhibited complete female sterility. The male and female floral organs of the mutant were morphologically indistinguishable from those of the wild type. We named the mutant srt1 for completely sterile and reduced tillering 1. Map-based cloning revealed that the mutant phenotypes were caused by a mutation in OsWUS. Compared with the two previously reported null allelic mutants of OsWUS (tab1-1 and moc3-1), which could produce partial N-terminal peptides of OsWUS, the srt1 protein contained a deletion of only seven amino acids within the conserved homeobox domain of OsWUS. However, the mutant phenotypes (monoculm and female sterility) displayed in srt1 were as typical and severe as those in tab1-1 and moc3-1. This indicates that the homeobox domain of SRT1 is essential for the regulation of tillering and sterility in rice. In addition, srt1 showed an opposite effect on panicle development to that of the two null allelic mutants, implying that the srt1 protein might still have partial or even new functions on panicle development. The results of this study suggest that the homeobox domain is pivotal for OsWUS function. PMID:27194802

  15. Mutation of OsGIGANTEA Leads to Enhanced Tolerance to Polyethylene Glycol-Generated Osmotic Stress in Rice.

    PubMed

    Li, Shuai; Yue, Wenhao; Wang, Min; Qiu, Wenmin; Zhou, Lian; Shou, Huixia

    2016-01-01

    Water deficit is one of the most important environmental stresses limiting plant growth and crop yield. While the identification of many key factors involved in the plant water deficit response has greatly increased our knowledge about the regulation system, the mechanisms underlying dehydration tolerance in plants are still not well understood. In our current study, we investigated the roles of the key flowering time regulator, OsGIGANTEA (OsGI), in the osmotic stress tolerance in rice. Results showed that mutation of OsGI conferred tolerance to osmotic stress generated by polyethylene glycol (PEG), increased proline and sucrose contents, and accelerated stomata movement. In addition, qRT-PCR and microarray analysis revealed that the transcript abundance of some osmotic stress response genes, such as OsDREB1E, OsAP37, OsAP59, OsLIP9, OsLEA3, OsRAB16A, and OsSalT, was significantly higher in osgi than in WT plants, suggesting that OsGI might be a negative regulator in the osmotic stress response in rice. PMID:27148296

  16. Fragile singlet ground-state magnetism in the pyrochlore osmates R2Os2O7 (R =Y and Ho)

    NASA Astrophysics Data System (ADS)

    Zhao, Z. Y.; Calder, S.; Aczel, A. A.; McGuire, M. A.; Sales, B. C.; Mandrus, D. G.; Chen, G.; Trivedi, N.; Zhou, H. D.; Yan, J.-Q.

    2016-04-01

    The singlet ground-state magnetism in pyrochlore osmates Y2Os2O7 and Ho2Os2O7 is studied by dc and ac susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected nonmagnetic singlet in the strong spin-orbit coupling (SOC) limit for Os4 + (5 d4 ), Y2Os2O7 exhibits a spin-glass ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the nonmagnetic state in the strong SOC limit and a magnetic state in the strong superexchange limit. Ho2Os2O7 has the same structural distortion as in Y2Os2O7 ; however, the Os sublattice in Ho2Os2O7 shows long-range magnetic ordering below 36 K. The sharp difference of the magnetic ground state between Y2Os2O7 and Ho2Os2O7 signals that the singlet ground-state magnetism in R2Os2O7 is fragile and can be disturbed by the weak 4 f -5 d interactions.

  17. Mutation of OsGIGANTEA Leads to Enhanced Tolerance to Polyethylene Glycol-Generated Osmotic Stress in Rice

    PubMed Central

    Li, Shuai; Yue, Wenhao; Wang, Min; Qiu, Wenmin; Zhou, Lian; Shou, Huixia

    2016-01-01

    Water deficit is one of the most important environmental stresses limiting plant growth and crop yield. While the identification of many key factors involved in the plant water deficit response has greatly increased our knowledge about the regulation system, the mechanisms underlying dehydration tolerance in plants are still not well understood. In our current study, we investigated the roles of the key flowering time regulator, OsGIGANTEA (OsGI), in the osmotic stress tolerance in rice. Results showed that mutation of OsGI conferred tolerance to osmotic stress generated by polyethylene glycol (PEG), increased proline and sucrose contents, and accelerated stomata movement. In addition, qRT-PCR and microarray analysis revealed that the transcript abundance of some osmotic stress response genes, such as OsDREB1E, OsAP37, OsAP59, OsLIP9, OsLEA3, OsRAB16A, and OsSalT, was significantly higher in osgi than in WT plants, suggesting that OsGI might be a negative regulator in the osmotic stress response in rice. PMID:27148296

  18. Ion probe measurements of Os, Ir, Pt, and Au in individual phases of iron meteorites

    NASA Astrophysics Data System (ADS)

    Hsu, Weibiao; Huss, Gary R.; Wasserburg, G. J.

    2000-03-01

    We have developed a technique to measure abundances of Os, Ir, Pt, and Au in situ in Fe-Ni metal on a microscale using secondary-ion mass spectrometry. A Cs + beam is used to generate negative secondary ions, and interferences from molecular ions are eliminated by a combination of 40 eV of energy filtering and a mass resolution of ˜1900. Ion yields for Fe, Co, Ni, and the PGEs vary considerably from spot to spot in meteoritic metal samples. Ion yield variations for Os and Ir correlate strongly with the Fe ion yield, that for Pt is weakly correlated, and that for Au is essentially uncorrelated. From ion yields for meteorite standards and the correlations with Fe ion yield, it is possible to obtain concentrations of Os, Ir, Pt, and Au in meteorite samples. Using this technique, a Cs + beam current of 10 nA gives a spatial resolution of 10-20 μm and detection limits of less than 1 ppm for Os, less than 0.1 ppm for Ir, and 10-20 ppb for Pt and Au. With refinement, it should be possible to measure Rh, Pd, and Ag and to improve the spatial resolution. However, Re, Ru, W, and Hf can only be measured as positive secondary ions. We have measured the abundances of Os, Ir, Pt, and Au in kamacite, taenite, and/or plessite in five iron meteorites: Canyon Diablo (IA), Cape York (Agpalilik) (IIIA), Colomera (IIE), Cruz del Aire (Anom), and Wallapai (IID). Our measurements show that Os, Ir, Pt, and Au partition preferentially into taenite relative to kamacite during slow cooling. Measured abundance ratios (taenite/kamacite) range from ˜1.3 to ˜2.1 for Os, Ir, and Pt, and from ˜2 to ˜6 for Au. These ratios are consistent with those determined recently by laser-ablation ICPMS, but differ significantly from those determined by earlier workers. Low-temperature taenite/kamacite distribution coefficients inferred from our data are ˜2.1 for Os, ˜1.6 for Ir, ˜1.9 for Pt, and ˜6 for Au. PGEs are not enriched in taenite as much as Ni. Partitioning is controlled by the interplay of

  19. Cloning, characterization and expression of OsFMO(t) in rice encoding a flavin monooxygenase.

    PubMed

    Yi, Jicai; Liu, Lanna; Cao, Youpei; Li, Jiazuo; Mei, Mantong

    2013-12-01

    Flavin monooxygenases (FMO) play a key role in tryptophan (Trp)-dependent indole-acetic acid (IAA) biosynthesis in plants and regulate plant growth and development. In this study, the full-length genomic DNA and cDNA of OsFMO(t), a FMO gene that was originally identified from a rolled-leaf mutant in rice, was isolated and cloned from wild type of the rolled-leaf mutant. OsFMO(t) was found to have four exons and three introns, and encode a protein with 422 amino acid residues that contains two basic conserved motifs, with a 'GxGxxG' characteristic structure. OsFMO(t) showed high amino acid sequence identity with FMO proteins from other plants, in particular with YUCCA from Arabidopsis, FLOOZY from Petunia, and OsYUCCA1 from rice. Our phylogenetic analysis showed that OsFMO(t) and the homologous FMO proteins belong to the same clade in the evolutionary tree. Overexpression of OsFMO(t) in transformed rice calli produced IAA-excessive phenotypes that showed browning and lethal effects when exogenous auxins such as naphthylacetic acid (NAA) were added to the medium. These results suggested that the OsFMO(t) protein is involved in IAA biosynthesis in rice and its overexpression could lead to the malformation of calli. Spatio-temporal expression analysis using RT-PCR and histochemical analysis for GUS activity revealed that expression of OsFMO(t) was totally absent in the rolled-leaf mutant. However, in the wild type variety, this gene was expressed at different levels temporally and spatially, with the highest expression observed in tissues with fast growth and cell division such as shoot apexes, tender leaves and root tips. Our results demonstrated that IAA biosynthesis regulated by OsFMO(t) is likely localized and might play an essential role in shaping local IAA concentrations which, in turn, is critical for regulating normal growth and development in rice. PMID:24371168

  20. 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

    2014-01-01

    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. PMID:25686220

  1. OsMADS26 Negatively Regulates Resistance to Pathogens and Drought Tolerance in Rice1[OPEN

    PubMed Central

    Khong, Giang Ngan; Richaud, Frédérique; Parizot, Boris; Mai, Chung Duc; Bès, Martine; Bourrié, Isabelle; Meynard, Donaldo; Beeckman, Tom; Selvaraj, Michael Gomez; Manabu, Ishitani; Brugidou, Christophe; Nang Do, Vinh; Guiderdoni, Emmanuel; Morel, Jean-Benoit; Gantet, Pascal

    2015-01-01

    Functional analyses of MADS-box transcription factors in plants have unraveled their role in major developmental programs (e.g. flowering and floral organ identity) as well as stress-related developmental processes, such as abscission, fruit ripening, and senescence. Overexpression of the rice (Oryza sativa) MADS26 gene in rice has revealed a possible function related to stress response. Here, we show that OsMADS26-down-regulated plants exhibit enhanced resistance against two major rice pathogens: Magnaporthe oryzae and Xanthomonas oryzae. Despite this enhanced resistance to biotic stresses, OsMADS26-down-regulated plants also displayed enhanced tolerance to water deficit. These phenotypes were observed in both controlled and field conditions. Interestingly, alteration of OsMADS26 expression does not have a strong impact on plant development. Gene expression profiling revealed that a majority of genes misregulated in overexpresser and down-regulated OsMADS26 lines compared with control plants are associated to biotic or abiotic stress response. Altogether, our data indicate that OsMADS26 acts as an upstream regulator of stress-associated genes and thereby, a hub to modulate the response to various stresses in the rice plant. PMID:26424158

  2. 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

  3. 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. PMID:18756558

  4. Pressure induced structural phase transition of OsB{sub 2}: First-principles calculations

    SciTech Connect

    Ren Fengzhu; Wang Yuanxu; Lo, V.C.

    2010-04-15

    Orthorhombic OsB{sub 2} was synthesized at 1000 deg. C and its compressibility was measured by using the high-pressure X-ray diffraction in a Diacell diamond anvil cell from ambient pressure to 32 GPa [R.W. Cumberland, et al. (2005)]. First-principles calculations were performed to study the possibility of the phase transition of OsB{sub 2}. An analysis of the calculated enthalpy shows that orthorhombic OsB{sub 2} can transfer to the hexagonal phase at 10.8 GPa. The calculated results with the quasi-harmonic approximation indicate that this phase transition pressure is little affected by the thermal effect. The calculated phonon band structure shows that the hexagonal P 6{sub 3}/mmc structure (high-pressure phase) is stable for OsB{sub 2}. We expect the phase transition can be further confirmed by the experimental work. - Abstract: Graphical Abstract Legend (TOC Figure): Table of Contents Figure Pressure induced structural phase transition from the orthorhombic structure to the hexagonal one for OsB{sub 2} takes place under 10.8 GPa (0 K), 10.35 GPa (300, 1000 K) by the first-principles predictions.

  5. Parámetros astrofísicos fundamentales de 6 cúmulos de la Nube Mayor de Magallanes en el rango de transición entre 200 y 700 millones de años

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Bica, E.; Geisler, D.; Clariá, J. J.

    Complementing our recent Washington photometric studies on intermediate age and young Large Magellanic Cloud (LMC) clusters, we present in this work new results for 6 previously unstudied star clusters in the transition range 200-700 Myr. We study NGC 1836, NGC 1860 and NGC 1865, which are projected on the LMC bar; SL 444, also located in the central disc but outside the bar, and LW 224 and SL 548, both located in the outer disc. We derive ages and metallicities from extracted T1 versus C-T1 colour-magnitude diagrams (CMDs), using theoretical isochrones recently computed for the Washington system. For the metallicity determinations, these CMDs are particularly sensitive. We also estimate ages and metallicities of the surrounding fields of NGC 1860 and NGC 1865 by employing the δT1 index and theoretical isochrones.

  6. Extreme Hf-Os Isotope Compositions in Hawaiian Peridotite Xenoliths: Evidence for an Ancient Recycled Lithosphere

    NASA Astrophysics Data System (ADS)

    Bizimis, M.; Lassiter, J. C.; Salters, V. J.; Sen, G.; Griselin, M.

    2004-12-01

    We report on the first combined Hf-Os isotope systematics of spinel peridotite xenoliths from the Salt Lake Crater (SLC), Pali and Kaau (PK) vents from the island of Oahu, Hawaii. These peridotites are thought to represent the Pacific oceanic lithosphere beneath Oahu, as residues of MORB-type melting at a paleo-ridge some 80-100Ma ago. Clinopyroxene mineral separates in these peridotites have very similar Nd and Sr isotope compositions with the post erosional Honolulu Volcanics (HV) lavas that bring these xenoliths to the surface. This and their relatively elevated Na and LREE contents suggest that these peridotites are not simple residues of MORB-type melting but have experience some metasomatic enrichment by the host HV lavas. However, the SLC and PK xenoliths show an extreme range in Hf isotope compositions towards highly radiogenic values (ɛ Hf= 7-80), at nearly constant Nd isotope compositions (ɛ Nd= 7-10), unlike any OIB or MORB basalt. Furthermore, these Oahu peridotites show a bimodal distribution in their bulk rock 187Os/186Os ratios: the PK peridotites have similar ratios to the abyssal peridotites (0.130-0.1238), while the SLC peridotites have highly subchondritic ratios (0.1237-0.1134) that yield 500Ma to 2Ga Re-depletion ages. Hf-Os isotopes show a broad negative correlation whereby the samples with the most radiogenic 176Hf/177Hf have the most unradiogenic 187Os/186Os ratios. Based on their combined Hf-Os-Nd isotope and major element compositions, the PK peridotites can be interpreted as fragments of the Hawaiian lithosphere, residue of MORB melting 80-100Ma ago, that have been variably metasomatized by the host HV lavas. In contrast, the extreme Hf-Os isotope compositions of the SLC peridotites suggest that they cannot be the source nor residue of any kind of Hawaiian lavas, and that Hf and Os isotopes survived the metasomatism or melt-rock reaction that has overprinted the Nd and Sr isotope compositions of these peridotites. The ancient (>1Ga

  7. 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.

  8. Inelastic neutron scttering study o fcrystal field levels in PrOs4As12

    SciTech Connect

    Chi, Songxue; Dai, Pengcheng; Barnes, Ted {F E }; Kang, H. J.; Lynn, J. W.; Ye, Feng; Maple, M. B.

    2008-01-01

    We use neutron scattering to study the Pr$^{3+}$ crystalline electric field (CEF) excitations in the filled skutterudite PrOs$_4$As$_{12}$. By comparing the observed levels and their strengths under neutron excitation with the theoretical spectrum and neutron excitation intensities, we identify the Pr$^{3+}$ CEF levels, and show that the ground state is a magnetic $\\Gamma_4^{(2)}$ triplet, and the excited states $\\Gamma_1$, $\\Gamma_4^{(1)}$ and $\\Gamma_{23}$ are at 0.4, 13 and 23~meV, respectively. A comparison of the observed CEF levels in PrOs$_4$As$_{12}$ with the heavy fermion superconductor PrOs$_4$Sb$_{12}$ reveals the microscopic origin of the differences in the ground states of these two filled skutterudites.

  9. Triaxial shape coexistence and new aligned band in {sup 178}Os

    SciTech Connect

    Kumar, Rajesh; Govil, I. M.; Dhal, A.; Chaturvedi, L.; Praharaj, C. R.; Rath, A. K.; Kumar, G. Kiran; Basu, S. K.; Chakraborty, A.; Krishichayan; Mukhopadhyay, S.; Pattabiraman, N. S.; Ghugre, S. S.; Sinha, A. K.

    2009-11-15

    High spin states in {sup 178}Os were studied by means of {sup 165}Ho({sup 20}Ne,p6n){sup 178}Os fusion evaporation reaction at a beam energy of 150 MeV, using a clover detector array. Several new transitions belonging to {sup 178}Os were placed in a level scheme and a new aligned rotational band was observed in addition to earlier known bands. Spin-parity assignments for most of the proposed levels were made using the deduced directional correlation orientation and polarization measurements for the de-exciting transitions. Experimental results are compared with the projected angular momentum deformed Hartree-Fock model calculations and cranked Woods-Saxon model calculations. This nucleus is predicted to be prolate deformed in the ground state but the {gamma}-softness at higher excitation is revealed by the cranked Woods-Saxon model and the geometrical asymmetric model calculations.

  10. Measurement of the Zeeman effect in an atomic anion: Prospects for laser cooling of Os-

    NASA Astrophysics Data System (ADS)

    Kellerbauer, A.; Fischer, A.; Warring, U.

    2014-04-01

    The negative osmium ion Os- is one of very few atomic anions potentially suitable for laser cooling. We have made a measurement of the Zeeman splitting of a bound-bound transition in 192Os- by studying the laser excitation from the 5d76s2 4F9/2e ground to the 5d66s26p 6D9/2o excited state in a homogeneous external magnetic field. The experimental Landé factors gJ=1.31(7) and gJ=1.50(8), respectively, agree well with calculated values. Both levels are found to split into 10 Zeeman sublevels, resulting in 28 allowed transitions of different relative intensities, in agreement with calculations based on pure and composite LS states. In view of the experimental results, the prospects for laser cooling of Os- are discussed.

  11. 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.

  12. Candidates for laser cooling of atomic anions: La{sup -} versus Os{sup -}

    SciTech Connect

    Pan, Lin; Beck, Donald R.

    2010-07-15

    This brief report is a follow-up to the recent proposal to use La{sup -} as another candidate, in addition to Os{sup -}, in laser cooling of anions, which can then be used to cool antiprotons sympathetically. Using the relativistic configuration interaction formalism, we calculate the photodetachment cross sections of the upper laser cooling state La{sup -} 5d6s{sup 2}6p {sup 3}D{sub 1} and Os{sup -} 5d{sup 6}6s{sup 2}6p {sup 6}D{sub 9/2}. Our results show that La{sup -} has a very similar two-photon detachment loss as Os{sup -}, retaining it as another promising candidate for cooling antiprotons sympathetically.

  13. Electronic correlations in the ferroelectric metallic state of LiOsO3

    NASA Astrophysics Data System (ADS)

    Lo Vecchio, I.; Giovannetti, G.; Autore, M.; Di Pietro, P.; Perucchi, A.; He, Jianfeng; Yamaura, K.; Capone, M.; Lupi, S.

    2016-04-01

    LiOsO3 has been recently identified as the first unambiguous "ferroelectric metal," experimentally realizing a prediction by Anderson and Blount [Phys. Rev. Lett. 14, 217 (1965), 10.1103/PhysRevLett.14.217]. In this Rapid Communication, we investigate the metallic state in LiOsO3 by means of infrared spectroscopy supplemented by density functional theory and dynamical mean-field theory calculations. Our measurements and theoretical calculations clearly show that LiOsO3 is a very bad metal with a small quasiparticle weight, close to a Mott-Hubbard localization transition. The agreement between experiments and theory allows us to ascribe all the relevant features in the optical conductivity to strong electron-electron correlations within the t2 g manifold of the osmium atoms.

  14. Structures and optical absorption of Bi2OS2 and LaOBiS2

    NASA Astrophysics Data System (ADS)

    Miura, Akira; Mizuguchi, Yoshikazu; Takei, Takahiro; Kumada, Nobuhiro; Magome, Eisuke; Moriyoshi, Chikako; Kuroiwa, Yoshihiro; Tadanaga, Kiyoharu

    2016-02-01

    The band gaps of isostructural Bi2OS2 and LaOBiS2 were examined using optical absorption and discussed with the band structures calculated based on the crystal structures determined using synchrotron X-ray diffraction. The Bi 6p and S 3p orbitals in the Bi-S plane were computationally predicted to constitute the bands near the Fermi level. The optical reflectance spectra of Bi2OS2 and LaOBiS2 showed optical band gaps of ~1.0 eV, which were close to the computationally calculated direct band gaps of ~0.8 eV. Our results show that Bi2OS2 and LaOBiS2 are semiconductors containing direct band gaps of 0.8-1.0 eV, and they are suggested to be candidates for optoelectronic materials in the near-infrared region without highly toxic elements.

  15. Support vector machine based IS/OS disruption detection from SD-OCT images

    NASA Astrophysics Data System (ADS)

    Wang, Liyun; Zhu, Weifang; Liao, Jianping; Xiang, Dehui; Jin, Chao; Chen, Haoyu; Chen, Xinjian

    2014-03-01

    In this paper, we sought to find a method to detect the Inner Segment /Outer Segment (IS/OS)disruption region automatically. A novel support vector machine (SVM) based method was proposed for IS/OS disruption detection. The method includes two parts: training and testing. During the training phase, 7 features from the region around the fovea are calculated. Support vector machine (SVM) is utilized as the classification method. In the testing phase, the training model derived is utilized to classify the disruption and non-disruption region of the IS/OS, and calculate the accuracy separately. The proposed method was tested on 9 patients' SD-OCT images using leave-one-out strategy. The preliminary results demonstrated the feasibility and efficiency of the proposed method.

  16. 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

  17. 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. PMID:27382137

  18. 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. PMID:27181944

  19. OsRDR6 plays role in host defense against double-stranded RNA virus, Rice Dwarf Phytoreovirus

    PubMed Central

    Hong, Wei; Qian, Dan; Sun, Runhong; Jiang, Lin; Wang, Yu; Wei, Chunhong; Zhang, Zhongkai; Li, Yi

    2015-01-01

    RNAi is a major antiviral defense response in plant and animal model systems. RNA-dependent RNA polymerase 6 (RDR6) is an essential component of RNAi, which plays an important role in the resistance against viruses in the model plants. We found previously that rice RDR6 (OsRDR6) functioned in the defense against Rice stripe virus (RSV), and Rice Dwarf Phytoreovirus (RDV) infection resulted in down-regulation of expression of RDR6. Here we report our new findings on the function of OsRDR6 against RDV. Our result showed that down-regulation of OsRDR6 through the antisense (OsRDR6AS) strategy increased rice susceptibility to RDV infection while over-expression of OsRDR6 had no effect on RDV infection. The accumulation of RDV vsiRNAs was reduced in the OsRDR6AS plants. In the OsRDR6 over-expressed plants, the levels of OsRDR6 RNA transcript and protein were much higher than that in the control plants. Interestingly, the accumulation level of OsRDR6 protein became undetectable after RDV infection. This finding indicated that the translation and/or stability of OsRDR6 protein were negatively impacted upon RDV infection. This new finding provides a new light on the function of RDR6 in plant defense response and the cross-talking between factors encoded by host plant and double-stranded RNA viruses. PMID:26165755

  20. 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).

  1. Does OsPHR2, central Pi-signaling regulator, regulate some unknown factors crucial for plant growth?

    PubMed Central

    Xu, Jiming

    2010-01-01

    OsPHR2, the homolog of AtPHR1, is a central Pi-signaling regulator. The Pi-signaling pathway downstream of AtPHR1, similarly of OsPHR2,1,2 involves a noncoding RNA which targets mimicry of miR399. miRNA399 mediates cleavage of PHO2.3,4 The regulating pathway downstream of OsPHR2 is negatively regulated by the Pi-signaling responsive gene OsSPX1.5,6 Overexpression of AtPHR1 and OsPHR2 leads to an increased concentration of Pi in the shoot tissues with leaf toxic symptom and growth retardation similar as the phenotype of pho2 mutant, especially under Pi abundant conditions.2,6,7 It has been known that the low affinity Pi transporter OsPT2 mainly contributes to the shoot Pi accumulation mediated by OsPHR2, and overexpression of OsPT2 results in shoot Pi accumulation and leaf toxic symptom and growth retardation under Pi abundant conditions.6 Two curious questions are emerging from the reported results: How Os SPX1 functions on the negative regulation of the pathway and what mechanism of the growth retardation mediated by OsPHR2. For the second question, our favored hypothesis is that the growth inhibition mediated by overexpression of OsPHR2 is caused by toxic physiological effects due to excessive Pi accumulation in shoots (Pi toxicity). In fact, the toxic symptoms become diminished with decreased Pi levels in growth medium. However, the plant growth retardation mediated by overexpression of OsPHR2 may be caused by some unknown genetic factor(s) regulated by OsPHR2. PMID:20404569

  2. Tri-axial Shape Coexistence and a New Aligned Band in {sup 178}Os

    SciTech Connect

    Govil, I. M.

    2009-03-10

    The Os nuclei lie in the beginning of the transitional region between the well deformed rare earth and spherical lead isotopes. The nuclei in this region are believed to be soft to changes in gamma deformation due to the softness of nuclear potential which may result in the shape coexistence. The neutron Fermi levels in Os nuclei from A = 170 to A = 186 lie in the middle of i{sub 13/2} orbital so that their shape in the ground state tends to take an appreciable prolate deformation. Hence collective bands with the well defined moment of inertia occur and the effect of different proton orbitals is observed as a modulation of the prolate structure. The anomalies in the yrast sequence, an effect attributed to change in moment of inertia of the ground state rotational band and the band crossing phenomena, are very important and vary strongly with neutron number in case of Os nuclei. The nuclear structure of {sup 178}Os nucleus has been studied using the reaction {sup 165}Ho({sup 20}Ne, p6n){sup 178}Os. Indian National Gamma Array (INGA) consisting of six Clover detectors with anti Compton shields was used for the detection of resulting gamma rays. The Direction Correlation of {gamma}-rays de-exciting Oriented states (DCO) ratio and polarization of gamma rays were measured to assign spin, parity and multipolarity of transitions. Twenty one new transitions belonging to the {sup 178}Os nucleus have been identified. The sudden and rather strong gain in aligned angular momentum is observed in the yrast band of {sup 178}Os. A new aligned rotational band similar to {sup 180}Os is also discovered in this nucleus. This band exhibits a very complex decay pattern with a single linking transition of 1778 keV to the ground state band. The tri-axial shape co-existence is also observed in this nucleus at higher excitation. The experimental results are compared with the Microscopic Hartree-Fock model calculations.

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

    PubMed

    Chagas-Neto, Francisco Abaete; de Souza, Barbara Nogueira Caracas; Nogueira-Barbosa, Marcello Henrique

    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

  4. 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

  5. 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.

  6. 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

  7. Urinary obstruction secondary to an ossifying fibroma of the os penis in a dog.

    PubMed

    Mirkovic, Tatjana K; Shmon, Cindy L; Allen, Andrew L

    2004-01-01

    A 13-year-old, 25-kg, castrated male border collie was referred for evaluation of pollakiuria, stranguria, and a decreased urine stream. A calcified periurethral mass near the caudal aspect of the os penis was identified on survey abdominal radiographs. A retrograde contrast urethrocystogram demonstrated that the mass was compressing the penile urethra. The mass was surgically resected. A histopathological diagnosis of an ossifying fibroma of the os penis was made. This report describes an atypical presentation of a rare tumor, an ossifying fibroma, that caused a urinary obstruction in a male dog. A review of the incidence, histopathological features, and behavior of ossifying fibromas is included. PMID:15007052

  8. 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.

  9. 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

  10. The Os-AKT1 channel is critical for K+ uptake in rice roots and is modulated by the rice CBL1-CIPK23 complex.

    PubMed

    Li, Juan; Long, Yu; Qi, Guo-Ning; Li, Juan; Xu, Zi-Jian; Wu, Wei-Hua; Wang, Yi

    2014-08-01

    Potassium (K(+)) is one of the essential nutrient elements for plant growth and development. Plants absorb K(+) ions from the environment via root cell K(+) channels and/or transporters. In this study, the Shaker K(+) channel Os-AKT1 was characterized for its function in K(+) uptake in rice (Oryza sativa) roots, and its regulation by Os-CBL1 (Calcineurin B-Like protein1) and Os-CIPK23 (CBL-Interacting Protein Kinase23) was investigated. As an inward K(+) channel, Os-AKT1 could carry out K(+) uptake and rescue the low-K(+)-sensitive phenotype of Arabidopsis thaliana akt1 mutant plants. Rice Os-akt1 mutant plants showed decreased K(+) uptake and displayed an obvious low-K(+)-sensitive phenotype. Disruption of Os-AKT1 significantly reduced the K(+) content, which resulted in inhibition of plant growth and development. Similar to the AKT1 regulation in Arabidopsis, Os-CBL1 and Os-CIPK23 were identified as the upstream regulators of Os-AKT1 in rice. The Os-CBL1-Os-CIPK23 complex could enhance Os-AKT1-mediated K(+) uptake. A phenotype test confirmed that Os-CIPK23 RNAi lines exhibited similar K(+)-deficient symptoms as the Os-akt1 mutant under low K(+) conditions. These findings demonstrate that Os-AKT1-mediated K(+) uptake in rice roots is modulated by the Os-CBL1-Os-CIPK23 complex. PMID:25096783

  11. K2NaOsO5.5 and K3NaOs2O9: The first osmium perovskites containing alkali cations at the “A” site

    NASA Astrophysics Data System (ADS)

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

    2012-07-01

    K2NaOsO5.5 and K3NaOs2O9 were obtained from solid-state reactions of potassium superoxide, sodium peroxide and osmium metal at elevated oxygen pressures. K2NaOsO5.5 crystallizes as an oxygen-deficient cubic double perovskite in space group Fm3¯m with a=8.4184(5) Å and contains isolated OsO6 octahedra. K3NaOs2O9 crystallizes hexagonally in P63/mmc with a=5.9998(4) Å and c=14.3053(14) Å. K3NaOs2O9 consists of face sharing Os2O9 pairs of octahedra. According to magnetic measurements K2NaOsO5.5 is diamagnetic, whereas K3NaOs2O9 displays strong antiferromagnetic coupling (TN=140 K), indicating enhanced magnetic interactions within the octahedral pair.

  12. Os-Ru-Ir and Os-(Ru)-Ir-Pt mineral phases from iron quartzites and weathered rocks of the Mikhailovka and Staryi Oskol KMA iron regions, central Russia

    NASA Astrophysics Data System (ADS)

    Chernyshov, N. M.; Ponamareva, M. M.

    2015-02-01

    Numerous natural Os-Ir-Ru and Os-Ir-Ru-Pt alloys have been found in iron quartzites and their weathered rocks. The Ir-Os alloys in the Mikhailovka and Staryi Oskol KMA iron regions are characterized by the densest hexagonal packing. Almost all of them contain a low amount of Fe and Ni at a relatively higher amount of Pt, Ru, and, locally, Rh. The highest Rh contents are typical of minerals with Ir dominant over Os or with a high Pt content.

  13. 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.

  14. 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.

  15. 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…

  16. Structure and physical properties of R2 Os2 O7 Pyrochlores

    NASA Astrophysics Data System (ADS)

    Rawl, Ryan; Calder, Stuart; Zhao, Zhiying; Zhou, Haidong; Mandrus, David; Yan, Jiaqiang

    2015-03-01

    The spin-orbit coupling (SOC) in 4d/5d transition metal oxides is enhanced to such a degree, relative to 3d oxides, that it can alter the electronic structure and have a dramatic effect on materials properties. A good example of this is the SOC assisted metal-insulator transition in Sr2IrO4, which has been extensively studied in the last few years. In a strong SOC scenario, a nonmagnetic ground state is expected for systems with d4 electronic configuration. R2Os2O7 pyrochlores, in which Os4 + has d4 electron count, provides a material playground to study the magnetism of d4 and effect of R3 +-Os4 + interplay on the ground states. This series has only undergone limited studies, with the only published data investigating the lattice parameters and electrical resistivity at room temperature. In this talk, I will report our study on the magnetic, transport, thermodynamic, and structural properties of R2Os2O7 pyrochlores. Part of the work was supported by the CEM, and NSF MRSEC, under Grant DMR-1420451.

  17. Magnetic and charge transport properties of the Na-based Os oxide pyrochlore

    SciTech Connect

    Shi, Y.G.; Belik, A.A.; Tachibana, M.; Tanaka, M.; Katsuya, Y.; Kobayashi, K.; Yamaura, K.; Takayama-Muromachi, E.

    2009-04-15

    The Na-based osmium oxide pyrochlore was synthesized for the first time by an ion-exchange method using KOs{sub 2}O{sub 6} as a host. The composition was identified as Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O by electron probe micro-analysis, thermogravimetric analysis, and structural analysis using synchrotron X-ray diffraction. Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O crystallizes in a regular pyrochlore structure with some defects (space group: Fd-3m, a=10.16851(1) A). Electrical resistivity, heat capacity, and magnetization measurements clearly showed absence of superconductivity down to 2 K, being in large contrast to what was found for the beta-type pyrochlore superconductor AOs{sub 2}O{sub 6} (A=Cs, Rb, and K). The Sommerfeld coefficient is 22 mJ K{sup -2} mol{sup -1}, being the smallest among AOs{sub 2}O{sub 6}. A magnetic anomaly at {approx}57 K and associated magneto-resistance (+3.7% at 2 K in 70 kOe) were found. - Graphical abstract: Crystal structure of the Na-based Os oxide pyrochlore Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O.

  18. 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.

  19. Microstructure and ordering parameter studies in multilayer [FePt(x)/Os]{sub n} films

    SciTech Connect

    Chiang, D. P.; Chen, S. Y.; Chen, Y. Y.; Yao, Y. D.; Ouyang, H.; Yu, C. C.; Lin, H. M.

    2011-04-01

    The microstructure, ordering parameter, and magnetic properties of multilayer [FePt(x)/Os]{sub n} films on glass substrate by dc-magnetron sputtering (with x being thickness in nm; Os with a fixed thickness 5 nm; n being the number of layers) have been studied as a function of the annealing temperatures between 300 and 900 deg. C. The grain size of multilayer films can be controlled by annealing temperature and thickness of the FePt layer with Os space layer. The coercivity as a function of the annealing temperature for samples with n = 1 and pure FePt behaves roughly saturated after annealing above 700 deg. C. However, for samples with n > 4 the value of H{sub c} seems still increasing with increasing annealing temperature between 600 and 900 deg. C, and the ordering parameter decreases with increasing the number of Os layers. Our experimental results are reasonably well to describe the effect of strain-assisted transformation.

  20. 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.

  1. 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…

  2. 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…

  3. 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.

  4. Formin homology 1 (OsFH1) regulates root-hair elongation in rice (Oryza sativa).

    PubMed

    Huang, Jin; Kim, Chul Min; Xuan, Yuan-hu; Liu, Jingmiao; Kim, Tae Ho; Kim, Bo-Kyeong; Han, Chang-deok

    2013-05-01

    The outgrowth of root hairs from the epidermal cell layer is regulated by a strict genetic regulatory system and external growth conditions. Rice plants cultivated in water-logged paddy land are exposed to a soil ecology that differs from the environment surrounding upland plants, such as Arabidopsis and maize. To identify genes that play important roles in root-hair growth, a forward genetics approach was used to screen for short-root-hair mutants. A short-root-hair mutant was identified, and the gene was isolated using map-based cloning and sequencing. The mutant harbored a point mutation at a splicing acceptor site, which led to truncation of OsFH1 (rice formin homology 1). Subsequent analysis of two additional T-DNA mutants verified that OsFH1 is important for root-hair elongation. Further studies revealed that the action of OsFH1 on root-hair growth is dependent on growth conditions. The mutant Osfh1 exhibited root-hair defects when roots were grown submerged in solution, and mutant roots produced normal root hairs in the air. However, root-hair phenotypes of mutants were not influenced by the external supply of hormones or carbohydrates, a deficiency of nutrients, such as Fe or P i , or aeration. This study shows that OsFH1 plays a significant role in root-hair elongation in a growth condition-dependent manner. PMID:23334469

  5. 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.

  6. 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.

  7. 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. PMID:27289219

  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. 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

  10. Efectos tardíos y el linfoma de Hodgkin en estadio inicial

    Cancer.gov

    Los pacientes con linfoma de Hodgkin en estadio inicial que recibieron varios fármacos de quimioterapia como único tratamiento, tenían más probabilidad de sobrevivir 12 años después que los pacientes que recibieron tratamiento que incluía radioterapia.

  11. Study of shape transition in the neutron-rich Os isotopes

    NASA Astrophysics Data System (ADS)

    John, P. R.; Modamio, V.; Valiente-Dobón, J. J.; Mengoni, D.; Gottardo, A.; Bazzacco, D.; Lunardi, S.; Alexander, T.; de Angelis, G.; Ashwood, N.; Barr, M.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; Bottoni, S.; Bowry, M.; Bracco, A.; Browne, F.; Bunce, M.; Gadea, A.; Camera, F.; Corradi, L.; Crespi, F. C. L.; Farnea, E.; Fioretto, E.; Kokalova, Tz.; Korten, W.; Kuşoğlu, A.; Lenzi, S.; Leoni, S.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D. R.; Podolyák, Zs.; Pollarolo, G.; Recchia, F.; Roberts, O. J.; Şahin, E.; Salsac, M.-D.; Scarlassara, F.; Stefanini, A. M.; Szilner, S.; Ur, C. A.; Walshe, J.; Wheldon, C.

    2014-03-01

    The neutron-rich isotopes of tungsten, osmium and platinum have different shapes in their ground states and present also shape transitions phenomena. Spectroscopic information for these nuclei is scarce and often limited to the gamma rays from the decay of isomeric states. For the neutron-rich even-even osmium isotopes 194Os and 198Os, a shape transition between a slightly prolate deformed to an oblate deformed ground state was deduced from the observed level schemes. For the even-even nucleus lying in between, 196Os, no gamma ray transition is known. In order to elucidate the shape transition and to test the nuclear models describing it, this region was investigated through gamma-ray spectroscopy using the AGATA demonstrator and the large acceptance heavy-ion spectrometer PRISMA at LNL, Italy. A two-nucleon transfer from a 198Pt target to a stable 82Se beam was utilized to populate medium-high spin states of 196Os. The analysis method and preliminary results, including the first life-time measurement of isomeric states with AGATA, are presented.

  12. 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. PMID:25641188

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

    PubMed

    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

  14. A novel technique of arthroscopic excision of a symptomatic os trigonum.

    PubMed

    Horibe, Shuji; Kita, Keisuke; Natsu-ume, Takashi; Hamada, Masayuki; Mae, Tatsuo; Shino, Konsei

    2008-01-01

    We describe a new arthroscopic excision technique for a symptomatic os trigonum. With the patient lying in a prone position, a posterolateral portal just lateral to the Achilles tendon, at the 5-mm level proximal to the tip of the fibula, is used for the arthroscope and an accessory posterolateral portal just posterior to the peroneal tendon at the same level is used for instruments. The synovial tissues are then debrided with a power shaver through the accessory posterolateral portal for better visualization. An elevator is used to release the fibrous tissue between the os trigonum and the talus. The os trigonum is completely excised with a grasper to visualize the flexor hallucis longus tendon. Radiographic control is helpful to check the position of the arthroscope if it happens to be inserted into the ankle joint as a result of the reduced subtalar joint space. Postoperatively, no immobilization is necessary, and full weight-bearing is allowed as tolerated. Three of us have performed 11 procedures with excellent results and no cases of complications. This arthroscopic excision technique for the symptomatic os trigonum is a safe and effective procedure. PMID:18182212

  15. 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…

  16. 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.

  17. 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...

  18. Latina/os in Rhetoric and Composition: Learning from Their Experiences with Language Diversity

    ERIC Educational Resources Information Center

    Cavazos, Alyssa Guadalupe

    2012-01-01

    "Latina/os in Rhetoric and Composition: Learning from their Experiences with Language Diversity" explores how Latina/o academics' experiences with language difference contributes to their Latina/o academic identity and success in academe while remaining connected to their heritage language and cultural background. Using qualitative…

  19. 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…

  20. 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…

  1. High continental weathering rate during Early Cambrian: Evidence from Os isotopic composition of Early Cambrian Ocean

    NASA Astrophysics Data System (ADS)

    Jiang, S.-Y.; Yang, J.-H.; Ling, H.-F.; Feng, H.-Z.; Chen, Y.-Q.; Chen, J.-H.

    2003-04-01

    The paleo-ocean environmental change during the Precambrian-Cambrian transition is a key issue related to the causes for an explosive radiation of different metazoan phyla during Early Cambrian. The chemical and isotopic compositions of marine sediments and chemical precipitates such as carbonates, phosphorites, siliceous rocks, and black shales record the changing composition and physical conditions of the seawater in which these rocks accumulated. Organic carbon-rich black shales from marine environments are commonly enriched in a number of trace elements such as Ni, Mo, V, Co, Cr, Au, U, As, Pb, Zn, Cu, Re, and platinum-group-elements (PGE). Recent researches have demonstrated that Re-Os isotopes and PGE contents in black shales are useful proxies for seawater chemistry. It is believed that Re and Os in orgainc-carbon rich black shales are mostly hydrogeneous in origin which were largely sequestered from seawater at the time of deposition. In South China, the Lower Cambrian black shale sequence of the Niutitang Formation (and lateral equivalents) exists broadly several thousands kilometers. The lowermost sequence of this formation contain a thin sulfide ore horizon with an apparently unique and extreme case of metal enrichments such as Mo, Ni, Se, Re, Os, As, Hg, Sb, Ag, Au, Pt, and Pd. In this study, we conducted a preliminary investigation of Re-Os isotopes and Plantium Group Element (PGE) distribution patterns of the balck shales and intercalated Ni-Mo polymetallic sulfide bed from Guizhou and Hunan Provinces. The high rOs(t) values of the black shales indicate that the Early Cambrian ocean in Yangtze Platform had a highly radiogenic Os, possibly as a result of high continental weathering rate at that time. The Ni-Mo polymetallic sulfide ores within the black shales have lower rOs(t) values than the black shales, and they show similar REE and PGE patterns as the hydrothermal siliceous rocks within the Lower Cambrian strata, which suggest that the Ni

  2. Osmium isotopes in Baffin Island and West Greenland picrites: Implications for the 187Os/ 188Os composition of the convecting mantle and the nature of high 3He/ 4He mantle

    NASA Astrophysics Data System (ADS)

    Dale, C. W.; Pearson, D. G.; Starkey, N. A.; Stuart, F. M.; Ellam, R. M.; Larsen, L. M.; Fitton, J. G.; Macpherson, C. G.

    2009-02-01

    Identifying the Os isotope composition of the prevalent, largely peridotitic, convecting mantle places important constraints on the Earth's accretion, differentiation and evolution and also has implications for the interpretation of Re-depletion ages in mantle peridotites. As partial melting preferentially samples mantle components with the lowest melting temperatures, large degree melts such as picrites should most closely reflect the peridotitic components within the source. Thus, Re-Os analyses of thirty picrites from Baffin Island and West Greenland are thought to provide a good estimate of the bulk 187Os/ 188Os composition of their convecting mantle source, which is indistinguishable from DMM in terms of lithophile isotopes and trace elements. In addition, the high 3He/ 4He of these rocks allows us to comment on the possible origins of high 3He/ 4He mantle. Ingrowth-corrected 187Os/ 188Os of the picrites ranges from 0.1267 to 0.1322. The higher 187Os/ 188Os samples have correspondingly lower 143Nd/ 144Nd which can be explained by contribution (˜ 5%) from old recycled oceanic crust, including sediment. However, Baffin Island and the earliest West Greenland picrites are remarkably uniform in composition with 187Os/ 188Os between 0.1267 and 0.1280, and a mean and mode of 0.1272 ± 0.0007. Such Os isotope compositions are less radiogenic than estimates of primitive upper mantle but are similar to the least radiogenic mid-ocean ridge basalts (MORB) and the most common composition of ophiolite-derived platinum-group alloys and chromites. These compositions appear to represent a source dominated by peridotite. The picrites studied record the highest known 3He/ 4He in the silicate Earth (up to 50 Ra). For this signature to reflect isolated domains of ancient melt depletion would require significantly less radiogenic Os isotope compositions than observed ( 187Os/ 188Os: < 0.115), unless radiogenic Os, but not He, has been subsequently added. Conversely, a bulk outer

  3. Re-Os geochronology on sulfides from the Tudun Cu-Ni sulfide deposit, Eastern Tianshan, and its geological significance

    NASA Astrophysics Data System (ADS)

    Wang, Minfang; Wang, Wei; Gutzmer, Jens; Liu, Kun; Li, Chao; Michałak, Przemysław P.; Xia, Qinlin; Guo, Xiaonan

    2015-11-01

    The Tudun deposit is a medium-sized Cu-Ni sulfide deposit, located at the westernmost edge of the Huangshan-Jing'erquan Belt in the northern part of Eastern Tianshan, NW China. Sulfide separates including pentlandite, pyrrhotite and chalcopyrite from the Tudun deposit, contain Re, common Os and 187Os ranging from 40.46 to 201.2, 0.8048 to 6.246 and 0.1709 to 0.9977 ppb, respectively. They have very low 187Os/188Os ratios of 1.224-2.352. The sulfides yield a Re-Os isochron age of 270.0 ± 7.5 Ma (MSWD = 1.3), consistent within uncertainty with the SHRIMP zircon U-Pb age for the Tudun mafic intrusion (gabbro) of 280.0 ± 3.0 Ma. The calculated initial 187Os/188Os ratio is 0.533 ± 0.022, and γOs values range from 283 to 307, with a mean of 297, indicating significant crustal contamination of the parent melt prior to sulfide saturation. The Tudun deposit shares the same age and Re-Os isotopic compositions with other orthomagmatic Cu-Ni sulfide deposits in Huangshan-Jing'erquan Belt, suggesting that they have formed in Early Permian.

  4. 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. PMID:27524243

  5. 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.

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

    PubMed Central

    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

  7. 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

  8. OsTIR1 and OsAFB2 Downregulation via OsmiR393 Overexpression Leads to More Tillers, Early Flowering and Less Tolerance to Salt and Drought in Rice

    PubMed Central

    Ou, Xiaojin; Fang, Zhongming; Tian, Changen; Duan, Jun; Wang, Yaqin; Zhang, Mingyong

    2012-01-01

    The microRNA miR393 has been shown to play a role in plant development and in the stress response by targeting mRNAs that code for the auxin receptors in Arabidopsis. In this study, we verified that two rice auxin receptor gene homologs (OsTIR1 and OsAFB2) could be targeted by OsmiR393 (Os for Oryza sativa). Two new phenotypes (increased tillers and early flowering) and two previously observed phenotypes (reduced tolerance to salt and drought and hyposensitivity to auxin) were observed in the OsmiR393-overexpressing rice plants. The OsmiR393-overexpressing rice demonstrated hyposensitivity to synthetic auxin-analog treatments. These data indicated that the phenotypes of OsmiR393-overexpressing rice may be caused through hyposensitivity to the auxin signal by reduced expression of two auxin receptor genes (OsTIR1 and OsAFB2). The expression of an auxin transporter (OsAUX1) and a tillering inhibitor (OsTB1) were downregulated by overexpression of OsmiR393, which suggested that a gene chain from OsmiR393 to rice tillering may be from OsTIR1 and OsAFB2 to OsAUX1, which affected the transportation of auxin, then to OsTB1, which finally controlled tillering. The positive phenotypes (increased tillers and early flowering) and negative phenotypes (reduced tolerance to salt and hyposensitivity to auxin) of OsmiR393-overexpressing rice present a dilemma for molecular breeding. PMID:22253868

  9. Effects of chemical pressure on the magnetic ground states of the osmate double perovskites SrCaCoOs O6 and C a2CoOs O6

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

    The magnetic ground state in the double perovskite system S r2 -xC axCoOs O6 changes from an antiferromagnet (x =0 ) , to a spin glass (x =1 ) , to a ferrimagnet (x =2 ) as the Ca content increases. This crossover is driven by chemical pressure effects that control the relative strength of magnetic exchange interactions. The synthesis, crystal structure, and magnetism of SrCaCoOs O6 and C a2CoOs O6 are investigated and compared with S r2CoOs O6 . Both compounds adopt a monoclinic crystal structure with rock-salt ordering of C o2 + and O s6 + and a-a-b+ octahedral tilting, but the average Co-O-Os bond angle evolves from 158.0 (3) ∘ in SrCaCoOs O6 to 150.54 (9) ∘ in C a2CoOs O6 as the smaller C a2 + ion replaces S r2 + . While this change may seem minor, it has a profound effect on the magnetism, changing the magnetic ground state from antiferromagnetic in S r2CoOs O6 (TN 1=108 K , TN 2=70 K ) , to a spin glass in SrCaCoOs O6 (Tf 1=32 K , Tf 2=13 K ) , to ferrimagnetic in C a2CoOs O6 (TC=145 K ) . In the first two compounds the observation of two transitions is consistent with weak coupling between the Co and Os sublattices.

  10. 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.

  11. Implications of 187Os isotopic heterogeneities in a mantle plume: evidence from Gorgona Island and Curaçao

    NASA Astrophysics Data System (ADS)

    Walker, Richard J.; Storey, Michael; Kerr, Andrew C.; Tarney, John; Arndt, Nicholas T.

    1999-03-01

    Recent work has suggested that the mafic-ultramafic volcanism in evidence throughout portions of the Caribbean, Central America, and northern South America, including the islands of Gorgona and Curaçao, was generated as part of a middle-Cretaceous, large igneous province. New Re-Os isochron results for tholeiitic basalts from Gorgona and Curaçao indicate crystallization ages of 89.2 ± 5.2 and 85.6 ± 8.1 Ma, respectively, consistent with reported Ar ages. The Gorgona ultramafic suite shows a large range in initial Os isotopic composition, with γ Os values ranging from -0.5 to +12.4. This large range reflects isotopic heterogeneities in the mantle source similar to those observed for modern ocean island basalts. In contrast to ocean island basalts, however, Os isotopic compositions do not correlate with variations in Nd, Sr, or Pb isotopic compositions, which are within the range of depleted mid-ocean ridge basalts. The processes that produced these rocks evidently resulted in the decoupling of Os isotopes from the Nd, Sr, and Pb isotopic systems. Picrites from Curaçao have very uniform, chondritic initial Os isotopic compositions, with initial γ Os values ranging only from -0.4 to ±1.4. Basalts from Curaçao, however, define an isochron with a 187Os-enriched initial isotopic composition (γ Os = +9.5). In contrast to the 187Os-enriched ultramafic rocks from Gorgona, the enrichment in these basalts could have resulted from lithospheric contamination. If the Gorgona and Curaçao rocks were derived from the same plume, Os results, combined with Sr, Nd, and Pb data indicate a heterogeneous plume, with multiple compositionally and isotopically distinct domains. The Os isotopic results require derivation of Os from a minimum of two distinct reservoirs, one with a composition very similar to the chondritic average and one with long-term enriched Re/Os. Oceanic crustal recycling has been invoked to explain most of the 187Os enrichments that have been observed in

  12. 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

  13. Genome-Wide Targets Regulated by the OsMADS1 Transcription Factor Reveals Its DNA Recognition Properties.

    PubMed

    Khanday, Imtiyaz; Das, Sanjukta; Chongloi, Grace L; Bansal, Manju; Grossniklaus, Ueli; Vijayraghavan, Usha

    2016-09-01

    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

  14. Rice phytochrome-interacting factor protien 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...

  15. 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...

  16. 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. PMID:22848448

  17. 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.

  18. Striatal long noncoding RNA Abhd11os is neuroprotective against an N-terminal fragment of mutant huntingtin in vivo.

    PubMed

    Francelle, Laetitia; Galvan, Laurie; Gaillard, Marie-Claude; Petit, Fanny; Bernay, Benoît; Guillermier, Martine; Bonvento, Gilles; Dufour, Noëlle; Elalouf, Jean-Marc; Hantraye, Philippe; Déglon, Nicole; de Chaldée, Michel; Brouillet, Emmanuel

    2015-03-01

    A large number of gene products that are enriched in the striatum have ill-defined functions, although they may have key roles in age-dependent neurodegenerative diseases affecting the striatum, especially Huntington disease (HD). In the present study, we focused on Abhd11os, (called ABHD11-AS1 in human) which is a putative long noncoding RNA (lncRNA) whose expression is enriched in the mouse striatum. We confirm that despite the presence of 2 small open reading frames (ORFs) in its sequence, Abhd11os is not translated into a detectable peptide in living cells. We demonstrate that Abhd11os levels are markedly reduced in different mouse models of HD. We performed in vivo experiments in mice using lentiviral vectors encoding either Abhd11os or a small hairpin RNA targeting Abhd11os. Results show that Abhd11os overexpression produces neuroprotection against an N-terminal fragment of mutant huntingtin, whereas Abhd11os knockdown is protoxic. These novel results indicate that the loss lncRNA Abhd11os likely contribute to striatal vulnerability in HD. Our study emphasizes that lncRNA may play crucial roles in neurodegenerative diseases. PMID:25619660

  19. The intronic minisatellite OsMin1 within a serine protease gene in the Chinese caterpillar fungus Ophiocordyceps sinensis.

    PubMed

    Zhang, Yong-Jie; Hou, Jun-Xiu; Zhang, Shu; Hausner, Georg; Liu, Xing-Zhong; Li, Wen-Jia

    2016-04-01

    Repetitive DNA sequences make up a significant portion of all genomes and may occur in intergenic, regulatory, coding, or even intronic regions. Partial sequences of a serine protease gene csp1 was previously used as a population genetic marker of the Chinese caterpillar fungus Ophiocordyceps sinensis, but its first intron region was excluded due to ambiguous alignment. Here in this study, we report the presence of a minisatellite OsMin1 within this intron, where a 20(19)-bp repeat motif is duplicated two to six times in different isolates. Fourteen intron alleles and 13 OsMin1 alleles were identified among 125 O. sinensis samples distributed broadly on the Tibetan Plateau. Two OsMin1 alleles were prevalent, corresponding to either two or five repeats of the core sequence motif. OsMin1 appears to be a single locus marker in the O. sinensis genome, but its origin is undetermined. Abundant recombination signals were detected between upstream and downstream flanking regions of OsMin1, suggesting that OsMin1 mutate by unequal crossing over. Geographic distribution, fungal phylogeny, and host insect phylogeny all significantly affected intron distribution patterns but with the greatest influence noted for fungal genotypes and the least for geography. As far as we know, OsMin1 is the first minisatellite found in O. sinensis and the second found in fungal introns. OsMin1 may be useful in designing an efficient protocol to discriminate authentic O. sinensis from counterfeits. PMID:26754819

  20. [Cloning and function analysis of the rice small GTP-binding protein gene OsPra2].

    PubMed

    Zhao, Zhiqiang; Fu, Yaping; Yang, Kun; Zhang, Yuman; Yan, Yongsheng; Fang, Rongxiang; Sun, Zongxiu; Chen, Xiaoying

    2008-12-01

    Gene expression in rice roots under nutritional stress was studied using micro array techniques. The results showed that when re-supplied with sufficient amounts of nutrition after nutrition stress, the expression of OsPra2 (a small G protein which is homologous with Pea Pra2 protein) decreased in the plants root tissue. The cDNA sequence of the OsPra2 gene and its promoter, which is about 1 kb upstream of the translation origin point, was obtained using RT-PCR and PCR approaches. The OsPra2 protein contains four conserved GTP/GDP binding domains and specific domain of Rab small G protein family. The expression of OsPra2 and GST fusion protein in onion epidermal cells showed that OsPra2 protein was localized in the membrane and nucleus of the cell. The fusion expression of OsPra2 promoter and GUS reporter gene in transgenic rice suggested that the OsPra2 promoter allowed GUS expression in coleoptiles and roots. Compared with wild type rice, OsPra2 over expressed transgenic rice showed an obvious dwarf phenotype which resembles the BR deficient rice. PMID:19306571

  1. 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

  2. Re-Os isotopic constraints on the evolution of the Bangong-Nujiang Tethyan oceanic mantle, Central Tibet

    NASA Astrophysics Data System (ADS)

    Huang, Qi-Shuai; Shi, Ren-Deng; O'Reilly, Suzanne Y.; Griffin, William L.; Zhang, Ming; Liu, De-Liang; Zhang, Xiao-Ran

    2015-05-01

    Geochemical (including Re-Os isotopic) studies of the mantle rocks of ophiolites in the Bangong-Nujiang suture zone in central Tibet have provided a coherent picture of the evolution of the Bangong-Nujiang Tethyan oceanic mantle from mid-ocean ridge (MOR) to subduction-zone (SSZ) settings. Clinopyroxene (cpx)-harzburgites and lherzolites in the Bangong Lake ophiolite were formed in a MOR setting, as demonstrated by the Cr# of spinels (< 0.60) and whole-rock LREE-depleted patterns. Suprachondritic 187Re/188Os ratios (up to 1.833) of cpx-harzburgites and their spinels can be explained by interaction with melts derived from high Re/Os sources. Re-depletion (TRD) model ages (0.48-0.55 Ga) suggest these rocks may represent a Pan-African domain beneath the Gondwana continent. High TiO2 contents of spinels and whole-rock samples imply that the lherzolites were formed through a refertilization process. Similarly, Re-Os isotopic systematics of sulfides in the lherzolites (187Re/188Os: 0.173-1.717, 187Os/188Os: 0.12646-0.17340) demonstrate that they are mixtures of primary and secondary sulfides. 187Os/188Os ratios (0.1211-0.1226) of whole-rock lherzolites give TRD ages of 0.73-0.97 Ga, indicating the presence of Neoproterozoic lithospheric mantle under the spreading ridges. Mantle rocks in the SSZ-type ophiolites from Bangong Lake, Dongqiao and Nagqu reflect the complex evolution of the Bangong-Nujiang oceanic mantle during the SSZ stage. Most harzburgites from the Bangong Lake ophiolite give TRD ages of 1.0-1.5 Ga, possibly representing relics of a Mesoproterozoic lithospheric mantle. However, three samples have both high Os contents (1.32-4.45 ppb) and near-chondritic 187Os/188Os (0.1260-0.1297), and may represent Mesozoic oceanic lithospheric mantle. 187Os/188Os ratios of dunites and harzburgites from the Dongqiao and Nagqu ophiolites vary from 0.1174 to 0.1316 and give TRD ages up to 1.43 Ga, also suggesting the existence of a Mesoproterozoic lithospheric mantle which

  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. 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.

  5. 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.

  6. Giant Magnetic Anisotropy of Co, Ru, and Os Adatoms on MgO (001) Surface.

    PubMed

    Ou, Xuedong; Wang, Hongbo; Fan, Fengren; Li, Zhengwei; Wu, Hua

    2015-12-18

    Large magnetic anisotropy energy (MAE) is desirable and critical for nanoscale magnetic devices. Here, using ligand-field level diagrams and density functional calculations, we well explain the very recent discovery [I. G. Rau et al., Science 344, 988 (2014)] that an individual Co adatom on a MgO (001) surface has a large MAE of more than 60 meV. More importantly, we predict that a giant MAE up to 110 meV could be realized for Ru adatoms on MgO (001), and even more for the Os adatoms (208 meV). This is a joint effect of the special ligand field, orbital multiplet, and significant spin-orbit interaction, in the intermediate-spin state of the Ru or Os adatoms on top of the surface oxygens. The giant MAE could provide a route to atomic scale memory. PMID:26722941

  7. Q value and half-life of double-electron capture in 184Os

    NASA Astrophysics Data System (ADS)

    Smorra, C.; Rodríguez, T. R.; Beyer, T.; Blaum, K.; Block, M.; Düllmann, Ch. E.; Eberhardt, K.; Eibach, M.; Eliseev, S.; Langanke, K.; Martínez-Pinedo, G.; Nagy, Sz.; Nörtershäuser, W.; Renisch, D.; Shabaev, V. M.; Tupitsyn, I. I.; Zubova, N. A.

    2012-10-01

    184Os has been excluded as a promising candidate for the search of neutrinoless double-electron capture. High-precision mass measurements with the Penning-trap mass spectrometer TRIGA-TRAP result in a marginal resonant enhancement with Δ=-8.89(58) keV excess energy to the 1322.152(22) keV 0+ excited state in 184W. State-of-the-art energy density functional calculations are applied for the evaluation of the nuclear matrix elements to the excited states predicting a strong suppression due to the large deformation of mother and daughter states. The half-life of the transition exceeds T1/2(184Os)≥1.3×1029 yr for an effective neutrino mass of 1 eV.

  8. 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.

  9. Spin-orbit coupling controlled ground state in Sr2ScOsO6

    DOE PAGESBeta

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

    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

  10. Use of Centrifugal Filter Devices to Concentrate Dengue Virus in Mosquito per os Infection Experiments

    PubMed Central

    Richard, Vaea; Viallon, Jérôme; Cao-Lormeau, Van-Mai

    2015-01-01

    Dengue virus (DENV) is an arbovirus transmitted to humans by the bite of infected Aedes mosquitoes. Experimental per os infection of mosquitoes with DENV is usually a preliminary step in virus/vector studies but it requires being able to prepare artificial blood-meals with high virus titers. We report here the convenient use of centrifugal filter devices to quickly concentrate DENV particles in cell-culture supernatants. The median viral titer in concentrated-supernatants was 8.50 log10 TCID50/mL. By using these DENV concentrated-supernatants to prepare infectious blood-meals in Aedes aegypti per os infection experiments, we obtained a mean mosquito-infection rate of 94%. We also evaluated the use of centrifugal filter devices to recover DENV particles from non-infectious blood-meals presented to infected mosquitoes through a feeding membrane to collect their saliva. PMID:26372347

  11. The origin of hyper-ferroelectricity in Li BO3 (B=V, Nb, Ta, Os)

    NASA Astrophysics Data System (ADS)

    He, Lixin; Li, Pengfei; Ren, Xinguo; Guo, G.-C.

    The electronic and structural properties of Li BO3 (B=V, Nb, Ta, Os) are investigated via first-principles methods. We show that Li BO3 are belong to the recently proposed hyperferroelectrics, i.e., they all have unstable longitudinal optical phonon modes. Especially, the ferroelectric-like instability in the metal LiOsO3 is a limiting case of a hyperferroelectrics, whose optical dielectric constant goes to infinity. We further show via an effective Hamiltonian that in contrast to normal proper ferroelectricity, in which the ferroelectric instability usually comes from long range coulomb interactions, the hyperferroelectric instability is due to the structure instability driven by the short range interactions. This could happen in systems with large ion size mismatches, which therefore provides a useful guidance in searching for novel hyperferroelectrics.

  12. Giant Magnetic Anisotropy of Co, Ru, and Os Adatoms on MgO (001) Surface

    NASA Astrophysics Data System (ADS)

    Ou, Xuedong; Wang, Hongbo; Fan, Fengren; Li, Zhengwei; Wu, Hua

    2015-12-01

    Large magnetic anisotropy energy (MAE) is desirable and critical for nanoscale magnetic devices. Here, using ligand-field level diagrams and density functional calculations, we well explain the very recent discovery [I. G. Rau et al., Science 344, 988 (2014)] that an individual Co adatom on a MgO (001) surface has a large MAE of more than 60 meV. More importantly, we predict that a giant MAE up to 110 meV could be realized for Ru adatoms on MgO (001), and even more for the Os adatoms (208 meV). This is a joint effect of the special ligand field, orbital multiplet, and significant spin-orbit interaction, in the intermediate-spin state of the Ru or Os adatoms on top of the surface oxygens. The giant MAE could provide a route to atomic scale memory.

  13. The filled skutterudite CeOs4As12: A hybridization gap semiconductor

    PubMed Central

    Baumbach, R. E.; Ho, P. C.; Sayles, T. A.; Maple, M. B.; Wawryk, R.; Cichorek, T.; Pietraszko, A.; Henkie, Z.

    2008-01-01

    X-ray diffraction, electrical resistivity, magnetization, specific heat, and thermoelectric power measurements are presented for single crystals of the new filled skutterudite compound CeOs4As12, which reveal phenomena that are associated with f-electron-conduction electron hybridization. Valence fluctuations or Kondo behavior dominates the physics down to T ∼ 135 K. The correlated electron behavior is manifested at low temperatures as a hybridization gap-insulating state. The small energy gap Δ1/kB ∼ 73 K, taken from fits to electrical resistivity data, correlates with the evolution of a weakly magnetic or nonmagnetic ground state, which is evident in the magnetization data below a coherence temperature Tcoh ∼ 45 K. Additionally, the low-temperature electronic specific heat coefficient is small, γ ∼ 19 mJ/mol K2. Some results for the nonmagnetic analogue compound LaOs4As12 are also presented for comparison purposes.

  14. 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.

  15. Degenerative arthritis of pseudoarticulation between the os peroneum and cuboid: a rare cause of lateral foot pain.

    PubMed

    Gökkuş, Kemal; Sagtas, Ergin; Demirci, Erkan; Saylik, Murat; Aydın, Ahmet Turan

    2015-03-01

    The painful os peroneum syndrome is widely recognized. It is often the result of trauma. However degenerative changes between the os peroneum and the articular facet is much rarer and we could only find two other case reports in the literature. This report concerns a middle aged woman with chronic plantar-lateral foot pain and a limp secondary to degenerative changes between the os peroneum and its articular facet with cuboid. The aim of this study is to remind to orthopaedic surgeons about painful os peroneum syndrome and to highlight the rarity of our case. In our case the mid term result of the excision of the os peroneum with painful articulation appear good, providing symptomatic pain relief with little alteration in the function of the foot. PMID:25682421

  16. Osteoporosis in men: findings from the Osteoporotic Fractures in Men Study (MrOS)

    PubMed Central

    Cawthon, Peggy M.; Shahnazari, Mohammad; Orwoll, Eric S.; Lane, Nancy E.

    2016-01-01

    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). PMID:26834847

  17. PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

    SciTech Connect

    Barnett, J. M.; 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.

  18. PNNL OS3700 Tritium Monitoring System Software and Hardware Operations Manual, Revision 0

    SciTech Connect

    Barnett, J M.; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carrell, Dorothy M.; Douglas, David D.; Carter, Gregory L.

    2005-11-09

    The PNNL OS3700 Tritium Monitoring System Software and Hardware Operations Manual describes herein how to install and operate the software and hardware on a personal computer in conjunction with the Berthold LB110 flow-through proportional counter detector system. 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.

  19. 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. PMID:20725824

  20. 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.

  1. 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. PMID:26874295

  2. 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

  3. 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

  4. Inactivation of the WNT5A Alternative Promoter B Is Associated with DNA Methylation and Histone Modification in Osteosarcoma Cell Lines U2OS and SaOS-2

    PubMed Central

    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

  5. Rice phenylalanine ammonia-lyase gene OsPAL4 is associated with broad spectrum disease resistance.

    PubMed

    Tonnessen, Bradley W; Manosalva, Patricia; Lang, Jillian M; Baraoidan, Marietta; Bordeos, Alicia; Mauleon, Ramil; Oard, James; Hulbert, Scot; Leung, Hei; Leach, Jan E

    2015-02-01

    Most agronomically important traits, including resistance against pathogens, are governed by quantitative trait loci (QTL). QTL-mediated resistance shows promise of being effective and long-lasting against diverse pathogens. Identification of genes controlling QTL-based disease resistance contributes to breeding for cultivars that exhibit high and stable resistance. Several defense response genes have been successfully used as good predictors and contributors to QTL-based resistance against several devastating rice diseases. In this study, we identified and characterized a rice (Oryza sativa) mutant line containing a 750 bp deletion in the second exon of OsPAL4, a member of the phenylalanine ammonia-lyase gene family. OsPAL4 clusters with three additional OsPAL genes that co-localize with QTL for bacterial blight and sheath blight disease resistance on rice chromosome 2. Self-pollination of heterozygous ospal4 mutant lines produced no homozygous progeny, suggesting that homozygosity for the mutation is lethal. The heterozygous ospal4 mutant line exhibited increased susceptibility to three distinct rice diseases, bacterial blight, sheath blight, and rice blast. Mutation of OsPAL4 increased expression of the OsPAL2 gene and decreased the expression of the unlinked OsPAL6 gene. OsPAL2 function is not redundant because the changes in expression did not compensate for loss of disease resistance. OsPAL6 co-localizes with a QTL for rice blast resistance, and is down-regulated in the ospal4 mutant line; this may explain enhanced susceptibility to Magnoporthe oryzae. Overall, these results suggest that OsPAL4 and possibly OsPAL6 are key contributors to resistance governed by QTL and are potential breeding targets for improved broad-spectrum disease resistance in rice. PMID:25515696

  6. 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. PMID:26525180

  7. Structure and expression of OsUBP6, an ubiquitin-specific protease 6 homolog in rice (Oryza sativa L.).

    PubMed

    Moon, Yea Kyung; Hong, Jong-Pil; Cho, Young-Chan; Yang, Sae-Jun; An, Gynheung; Kim, Woo Taek

    2009-11-30

    Although the possible cellular roles of several ubiquitin-specific proteases (UBPs) were identified in Arabidopsis, almost nothing is known about UBP homologs in rice, a monocot model plant. In this report, we searched the rice genome database ( http://signal.salk.edu/cgi-bin/RiceGE ) and identified 21 putative UBP family members (OsUBPs) in the rice genome. These OsUBP genes each contain a ubiquitin carboxyl-terminal hydrolase (UCH) domain with highly conserved Cys and His boxes and were subdivided into 9 groups based on their sequence identities and domain structures. RT-PCR analysis indicated that rice OsUBP genes are expressed at varying degrees in different rice tissues. We isolated a full-length cDNA clone for OsUBP6, which possesses not only a UCH domain, but also an N-terminal ubiquitin motif. Bacterially expressed OsUBP6 was capable of dismantling K48-linked tetraubiquitin chains in vitro. Quantitative real-time RT-PCR indicated that OsUBP6 is constitutively expressed in different tissues of rice plants. An in vivo targeting experiment showed that OsUBP6 is predominantly localized to the nucleus in onion epidermal cells. We also examined how knock-out of OsUBP6 affects developmental growth of rice plants. Although homozygous T3 osubp6 T-DNA insertion mutant seedlings displayed slower growth relative to wild type seedlings, mature mutant plants appeared to be normal. These results raise the possibility that loss of OsUBP6 is functionally compensated for by an as-yet unknown OsUBP homolog during later stages of development in rice plants. PMID:19855938

  8. Molecular identification and interaction assay of the gene (OsUbc13) encoding a ubiquitin-conjugating enzyme in rice.

    PubMed

    Wang, Ya; Xu, Meng-yun; Liu, Jian-ping; Wang, Mu-gui; Yin, Hai-qing; Tu, Ju-min

    2014-07-01

    The ubiquitin (Ub)-conjugating enzyme, Ubc13, has been known to be involved in error-free DNA damage tolerance (or post-replication repair) via catalyzing Lys63-linked polyubiquitin chains formation together with a Ubc variant. However, its functions remain largely unknown in plant species, especially in monocotyledons. In this study, we cloned a Ub-conjugating enzyme, OsUbc13, that shares the conserved domain of Ubc with AtUBC13B in Oryza sativa L., which encodes a protein of 153 amino acids; the deduced sequence shares high similarities with other homologs. Real-time quantitative polymerase chain reaction (PCR) indicated that OsUbc13 transcripts could be detected in all tissues examined, and the expression level was higher in palea, pistil, stamen, and leaf, and lower in root, stem, and lemma; the expression of OsUbc13 was induced by low temperature, methylmethane sulfate (MMS), and H(2)O(2), but repressed by mannitol, abscisic acid (ABA), and NaCl. OsUbc13 was probably localized in the plasma and nuclear membranes. About 20 proteins, which are responsible for the positive yeast two-hybrid interaction of OsUbc13, were identified. These include the confirmed OsVDAC (correlated with apoptosis), OsMADS1 (important for development of floral organs), OsB22EL8 (related to reactive oxygen species (ROS) scavenging and DNA protection), and OsCROC-1 (required for formation of Lys63 polyubiquitylation and error-free DNA damage tolerance). The molecular characterization provides a foundation for the functional study of OsUbc13. PMID:25001222

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

    USGS Publications Warehouse

    Walker, R.J.; Shirey, S.B.; Hanson, G.N.; Rajamani, V.; Horan, M.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 reveal at least two episodes of post-magmatic alteration that affected these systems. The Re-Os isotopic systematics of many of the rocks of the belt indicate that Os was introduced to the area via fluids that carried very radiogenic Os ( 187Os 186Os2.4Ga > 39). The source of the radiogenic Os was likely ancient crust. On an outcrop scale, this alteration is also characterized by relatively minor additions of excess 87Sr and ??18O values higher than magmatic. The Rb-Sr systematics of most of these rocks are consistent with closed-system behavior since a period between 2700 and 2400 Ma ago, indicating that the alteration event likely occurred no later than the early Proterozoic. In contrast to this late Archean or early Proterozoic alteration, samples of several komatiitic amphibolites have very 187Os-depleted compositions, indicating that open-system behavior also occurred at a much later time. This alteration may have been caused by surficial weathering or the interaction of the rocks with fluids bearing unradiogenic Os. Results suggest that the Re-Os system may have only limited utility for geochronologic applications in regions for which post-crystallization noble metal mineralization is evident (e.g., gold ores). In such regions, however, the system may have an important application in assessing the timing and the ultimate sources of noble metal additions. ?? 1989.

  10. A TinyOS-enabled MICA2-based wireless neural interface.

    PubMed

    Farshchi, Shahin; Nuyujukian, Paul H; Pesterev, Aleksey; Mody, Istvan; Judy, Jack W

    2006-07-01

    Existing approaches used to develop compact low-power multichannel wireless neural recording systems range from creating custom-integrated circuits to assembling commercial-off-the-shelf (COTS) PC-based components. Custom-integrated-circuit designs yield extremely compact and low-power devices at the expense of high development and upgrade costs and turn-around times, while assembling COTS-PC-technology yields high performance at the expense of large system size and increased power consumption. To achieve a balance between implementing an ultra-compact custom-fabricated neural transceiver and assembling COTS-PC-technology, an overlay of a neural interface upon the TinyOS-based MICA2 platform is described. The system amplifies, digitally encodes, and transmits neural signals real-time at a rate of 9.6 kbps, while consuming less than 66 mW of power. The neural signals are received and forwarded to a client PC over a serial connection. This data rate can be divided for recording on up to 6 channels, with a resolution of 8 bits/sample. This work demonstrates the strengths and limitations of the TinyOS-based sensor technology as a foundation for chronic remote biological monitoring applications and, thus, provides an opportunity to create a system that can leverage from the frequent networking and communications advancements being made by the global TinyOS-development community. PMID:16830946

  11. 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.

  12. 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.

  13. 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.

  14. Os-coated cathode for very high emission-density applications

    NASA Astrophysics Data System (ADS)

    Shih, Arnold; Berry, Alan; Marrian, Christie R. K.; Haas, George A.

    1987-05-01

    Emission densities of 35 to 100 A/sq cm, demanded by free-electron lasers (FELs), have set far more stringent requirements on thermionic cathodes than what is considered state of the art with current technology. The purpose of the work considered here is to evaluate Os-coated cathodes for these ultrahigh-current-density applications. Organometallic CVD techniques were used to coat 'B' type tungsten dispenser cathodes. The coatings were found to show good adhesion and rapid activation. The activation process involves not only the standard formation of a BaO layer on the surface but also the formation of an optimum surface alloy composition of near 50-percent Os and 50-percent W. These cathodes showed excellent emission capabilities, and at a brightness temperature of 1085 C, a zero-field emission density near 50 A/sq cm was obtained. Subsequent life studies at a brightness temperature of 1085 C indicated that at an emission level of 40-50 A/sq cm over 800 h of life is obtainable with this type of cathode. During life, the pulsed emission density and surface composition were monitored. Surface Ba/BaO coverage as well as surface Os content were observed to decrease with life, but an S impurity was found to increase with life. However, the surface alloy composition change was identified as being the major cause for the emission degradation.

  15. OsCAND1 is required for crown root emergence in rice.

    PubMed

    Wang, Xiao-Fei; He, Fen-Fang; Ma, Xiao-Xia; Mao, Chuan-Zao; Hodgman, Charlie; Lu, Chun-Gui; Wu, Ping

    2011-03-01

    Crown roots are main components of the fibrous root system and important for crops to anchor and absorb water and nutrition. To understand the molecular mechanisms of crown root formation, we isolated a rice mutant defective in crown root emergence designated as Oscand1 (named after the Arabidopsis homologous gene AtCAND1). The defect of visible crown root in the Oscand1 mutant is the result of cessation of the G2/M cell cycle transition in the crown root meristem. Map-based cloning revealed that OsCAND1 is a homolog of Arabidopsis CAND1. During crown root primordium development, the expression of OsCAND1 is confined to the root cap after the establishment of fundamental organization. The transgenic plants harboring DR5::GUS showed that auxin signaling in crown root tip is abnormal in the mutant. Exogenous auxin application can partially rescue the defect of crown root development in Oscand1. Taken together, these data show that OsCAND1 is involved in auxin signaling to maintain the G2/M cell cycle transition in crown root meristem and, consequently, the emergence of crown root. Our findings provide new information about the molecular regulation of the emergence of crown root in rice. PMID:20978084

  16. Photodisintegration of the isotopes 186,188,189,190,192Os: Similarities and distinctions

    NASA Astrophysics Data System (ADS)

    Varlamov, V. V.; Makarov, M. A.; Peskov, N. N.; Stepanov, M. E.

    2015-09-01

    In addition to the results obtained earlier for the isotopes 188,189Os, experimental data on the photodisintegration of the isotopes 186,190,192Os 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, 1 n), ( γ, 2 n), and ( γ, 3 n) 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 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, 1 n) + 2 σ( γ, 2 n) + 3 σ( γ, 3 n) +... 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 186,190,192Os, new evaluated data satisfying the data-reliability criteria are obtained for the cross sections for partial and total photoneutron reactions.

  17. 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.

  18. 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.

  19. Etnografía acelerada para transformar normas sociales sobre género y sexualidad en hombres puertorriqueños heterosexuales1,2

    PubMed Central

    Ortiz-Torres, Blanca; Rivera-Ortiz, Rafael J.; Mendoza, Sigrid

    2014-01-01

    Resumen La construcción de roles de género dominantes contribuyen al riesgo de contraer VIH, y por tal razón se ha urgido a que se integren las normas sociales relativas al género en las intervenciones preventivas del VIH. Este estudio pretende adaptar y desarrollar una intervención que facilite la transformación de normas sociales del género y de prácticas sexuales en hombres puertorriqueños. La intervención propone transformar normas sociales relacionadas al género y sexualidad en barras comunitarias utilizando el modelo de líderes de opinión. Luego de ser elegidos/as, los/as líderes de opinión diseminan mensajes integrando la importancia de relaciones equitativas entre parejas para la prevención del VIH. La primera fase de esta intervención es discutida en este artículo, la cual incluye un proceso de etnografía acelerada para identificar los escenarios comunitarios en los que podemos desarrollar esta intervención y permitirnos entender la cultura de las barras comunitarias. A partir de las observaciones etnográficas, pudimos: desarrollar un protocolo de seguridad para realizar las observaciones, desarrollar un perfil de la cultura de las barras, elegir las barras a participar en las dos condiciones del estudio y adaptar los instrumentos de la intervención para que respondieran a la particularidad de los/as participantes. PMID:25530828

  20. 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

  1. 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

  2. Overexpression of rice glutaredoxins (OsGrxs) significantly reduces arsenite accumulation by maintaining glutathione pool and modulating aquaporins in yeast.

    PubMed

    Verma, Pankaj Kumar; Verma, Shikha; Meher, Alok Kumar; Pande, Veena; Mallick, Shekhar; Bansiwal, Amit Kumar; Tripathi, Rudra Deo; Dhankher, Om Parkash; Chakrabarty, Debasis

    2016-09-01

    Arsenic (As) is an acute poison and class I carcinogen, can cause a serious health risk. Staple crops like rice are the primary source of As contamination in human food. Rice grown on As contaminated areas accumulates higher As in their edible parts. Based on our previous transcriptome data, two rice glutaredoxins (OsGrx_C7 and OsGrx_C2.1) were identified that showed up-regulated expression during As stress. Here, we report OsGrx_C7 and OsGrx_C2.1 from rice involved in the regulation of intracellular arsenite (AsIII). To elucidate the mechanism of OsGrx mediated As tolerance, both OsGrxs were cloned and expressed in Escherichia coli (Δars) and Saccharomyces cerevisiae mutant strains (Δycf1, Δacr3). The expression of OsGrxs increased As tolerance in E. coli (Δars) mutant strain (up to 4 mM AsV and up to 0.6 mM AsIII). During AsIII exposure, S. cerevisiae (Δacr3) harboring OsGrx_C7 and OsGrx_C2.1 have lower intracellular AsIII accumulation (up to 30.43% and 24.90%, respectively), compared to vector control. Arsenic accumulation in As-sensitive S. cerevisiae mutant (Δycf1) also reduced significantly on exposure to inorganic As. The expression of OsGrxs in yeast maintained intracellular GSH pool and increased extracellular GSH concentration. Purified OsGrxs displays in vitro GSH-disulfide oxidoreductase, glutathione reductase and arsenate reductase activities. Also, both OsGrxs are involved in AsIII extrusion by altering the Fps1 transcripts in yeast and protect the cell by maintaining cellular GSH pool. Thus, our results strongly suggest that OsGrxs play a crucial role in the maintenance of the intracellular GSH pool and redox status of the cell during both AsV and AsIII stress and might be involved in regulating intracellular AsIII levels by modulation of aquaporin expression and functions. PMID:27174139

  3. Os isotope heterogeneity of the upper mantle: Evidence from the Mayarí Baracoa ophiolite belt in eastern Cuba

    NASA Astrophysics Data System (ADS)

    Frei, R.; Gervilla, F.; Meibom, A.; Proenza, J. A.; Garrido, C. J.

    2006-01-01

    In an attempt to quantify the extent of geochemical heterogeneity within a restricted and well dated portion of the upper mantle, 27 chromite separates from the 90 My old chromite deposits in the Mayarí-Baracoa ophiolite belt in eastern Cuba have been investigated for platinum group element (PGE) concentrations and Re-Os isotopic systematics. The samples are characterized by systematically subchondritic initial 187Os/ 188Os ratios and substantial heterogeneity. The initial 187Os/ 188Os ratios vary with chromite chemistry and with geographical distribution, reflecting differences in the Os isotopic evolution for the different upper mantle sections represented by the ophiolite. Accordingly, the Os isotope data might be divided into three groups. In the Moa-Baracoa district, where the chromite bodies are located in the mantle-crust transition zone, the calculated initial γOs values average - 0.97 ± 0.69 ( n = 13). In the Sagua de Tanamo district, where chromite chemistry is highly variable and their location in relation the mantle sequence is less clear, the initial γOs values are intermediate, with an average of - 1.77 ± 0.80 ( n = 7). In the Mayarí district, where the chromite bodies are located in the lower part of the mantle sequence, initial γOs values average - 2.66 ± 0.29 ( n = 7). These subchondritic (i.e. negative) initial γOs values are most simply explained by Re depletion during ancient partial melting and/or melt percolation events. The Os isotope heterogeneity documented here indicates a high degree of geochemical complexity on small to intermediate length scales in the upper mantle. Our results, in combination with data on chromites from the literature, show that an "average present-day Os isotopic composition" for the hypothetical depleted MORB mantle (DMM) reservoir cannot be precisely established beyond the statement that it is "broadly chondritic". Indeed, the upper mantle cannot be considered a sufficiently homogeneous geochemical

  4. Etude des relations entre photosynthese respiration, transpiration et nutrition minerale chez le ble

    NASA Astrophysics Data System (ADS)

    André, M.; Ducloux, H.; Richaud, C.; Massimino, D.; Daguenet, A.; Massimino, J.; Gerbaud, A.

    La croissance du Blé Triticum aestivum a été étudiée en environnement contrôlé et fermé pendant une période de 70 jours. Les échanges gazeux (Photosynthèse, Respiration) hydriques (Transpiration) et la consommation en éléments minéraux (Azote, Phosphore, Potassium) ont été mesurés en continu. On présentera les relations dynamiques observées entre les différentes fonctions physiologiques, d'une part sous l'influence de la croissance et d'autre part en réponse à des modifications de l'environnement. L'influence de la teneur en CO2 pendant la croissance (teneur normale ou doublée) sera mise en évidence.

  5. Indigenous Schooling Grants in Chile: The Impacts of an Integrationist Affirmative Action Policy among Mapuche Pupils

    ERIC Educational Resources Information Center

    Webb, Andrew

    2015-01-01

    This article assesses the extent to which indigenous grants administered to school pupils and university students in Chile can be considered affirmative action towards social justice. Drawing on Fraser's framework for parity of participation, I question whether the grants are able to provide both redistribution and recognition for indigenous…

  6. 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

  7. No Financial Disincentive for Choosing More Healthful Entrées on Children’s Menus in Full-Service Restaurants

    PubMed Central

    West, Delia

    2013-01-01

    Children are eating restaurant foods more than ever before, and price is among the top considerations for food choices. We categorized and enumerated entrées on children’s menus from 75 full-service restaurant chains to compare prices of more healthful and less healthful entrées to test the assumption that more healthful food is more expensive. The mean (standard deviation) price of more healthful entrées ($5.38 [$2.01]) was not significantly different from the price of less healthful entrées ($5.27 [$2.04]). In contrast to research demonstrating that more healthful foods tend to be more expensive in grocery stores, more healthful entrées on children’s menus in restaurants were not more expensive than less healthful entrées. PMID:23742942

  8. Role of OsPHR2 on phosphorus homeostasis and root hairs development in rice (Oryza sativa L.)

    PubMed Central

    Wang, XM

    2008-01-01

    AtPHR1 plays a central role in Pi-starvation signaling in Arabidopsis (Arabidopsis thaliana). Two PHR genes were isolated from rice and designated as OsPHR1 and OsPHR2 based on amino acid sequence homology to AtPHR1. Transgenic plants with overexpression and repression of OsPHR1 and OsPHR2, respectively, were used for investigation of roles of the genes in Pi-signaling pathway and Pi homeostasis under Pi-sufficient and deficient conditions. The results showed that both of the genes are involved in the Pi-signaling pathway, while overexpression of OsPHR2 mimics Pi-starvation stress with enhanced root elongation and proliferated root hairs, and results in the excessive accumulation of Pi in shoots under Pi-sufficient conditions. OsPHR2 regulated proliferation of root hair growth and root elongation suggests that OsPHR2 is involved in both systematic and local Pi-signaling pathways. PMID:19704822

  9. Enhancing blast disease resistance by overexpression of the calcium-dependent protein kinase OsCPK4 in rice.

    PubMed

    Bundó, Mireia; Coca, María

    2016-06-01

    Rice is the most important staple food for more than half of the human population, and blast disease is the most serious disease affecting global rice production. In this work, the isoform OsCPK4 of the rice calcium-dependent protein kinase family is reported as a regulator of rice immunity to blast fungal infection. It shows that overexpression of OsCPK4 gene in rice plants enhances resistance to blast disease by preventing fungal penetration. The constitutive accumulation of OsCPK4 protein prepares rice plants for a rapid and potentiated defence response, including the production of reactive oxygen species, callose deposition and defence gene expression. OsCPK4 overexpression leads also to constitutive increased content of the glycosylated salicylic acid hormone in leaves without compromising rice yield. Given that OsCPK4 overexpression was known to confer also salt and drought tolerance in rice, the results reported in this article demonstrate that OsCPK4 acts as a convergence component that positively modulates both biotic and abiotic signalling pathways. Altogether, our findings indicate that OsCPK4 is a potential molecular target to improve not only abiotic stress tolerance, but also blast disease resistance of rice crops. PMID:26578239

  10. A lipid transfer protein, OsLTPL36, is essential for seed development and seed quality in rice.

    PubMed

    Wang, Xin; Zhou, Wei; Lu, Zhanhua; Ouyang, Yidan; O, Chol Su; Yao, Jialing

    2015-10-01

    Storage lipid is a vital component for maintaining structure of seed storage substances and valuable for rice quality and food texture. However, the knowledge of lipid transporting related genes and their function in seed development have not been well elucidated yet. In this study, we identified OsLTPL36, a homolog of putative lipid transport protein, and showed specific expression in rice developing seed. Transcriptional profiling and in situ hybridization analysis confirmed that OsLTPL36 was exclusively expressed in developing seed coat and endosperm aleurone cells. Down-regulated expression of OsLTPL36 led to decreased seed setting rate and 1000-grain weight in transgenic plants. Further studies showed that suppressed expression of OsLTPL36 caused chalky endosperm and resulted in reduced fat acid content in RNAi lines as compared with wild type (WT). Histological analysis showed that the embryo development was delayed after down regulation of OsLTPL36. Moreover, impeded seed germination and puny seedling were also observed in the OsLTPL36 RNAi lines. The data demonstrated that OsLTPL36, a lipid transporter, was critical important not only for seed quality but also for seed development and germination in rice. PMID:26398804

  11. 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.

  12. Ectopic Overexpression of The Transcription Factor OsGLK1 Induces Chloroplast Development in Non-Green Rice Cells

    PubMed Central

    Nakamura, Hidemitsu; Muramatsu, Masayuki; Hakata, Makoto; Ueno, Osamu; Nagamura, Yoshiaki; Hirochika, Hirohiko; Takano, Makoto; Ichikawa, Hiroaki

    2009-01-01

    For systematic and genome-wide analyses of rice gene functions, we took advantage of the full-length cDNA overexpresser (FOX) gene-hunting system and generated >12 000 independent FOX-rice lines from >25 000 rice calli treated with the rice-FOX Agrobacterium library. We found two FOX-rice lines generating green calli on a callus-inducing medium containing 2,4-D, on which wild-type rice calli became ivory yellow. In both lines, OsGLK1 cDNA encoding a GARP transcription factor was ectopically overexpressed. Using rice expression-microarray and northern blot analyses, we found that a large number of nucleus-encoded genes involved in chloroplast functions were highly expressed and transcripts of plastid-encoded genes, psaA, psbA and rbcL, increased in the OsGLK1-FOX calli. Transmission electron microscopy showed the existence of differentiated chloroplasts with grana stacks in OsGLK1-FOX calli cells. However, in darkness, OsGLK1-FOX calli did not show a green color or develop grana stacks. Furthermore, we found developed chloroplasts in vascular bundle and bundle sheath cells of coleoptiles and leaves from OsGLK1-FOX seedlings. The OsGLK1-FOX calli exhibited high photosynthetic activity and were able to grow on sucrose-depleted media, indicating that developed chloroplasts in OsGLK1-FOX rice calli are functional and active. We also observed that the endogenous OsGLK1 mRNA level increased synchronously with the greening of wild-type calli after transfer to plantlet regeneration medium. These results strongly suggest that OsGLK1 regulates chloroplast development under the control of light and phytohormones, and that it is a key regulator of chloroplast development. PMID:19808806

  13. 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.

  14. OsGL1-3 is Involved in Cuticular Wax Biosynthesis and Tolerance to Water Deficit in Rice

    PubMed Central

    Zhou, Xiaoyun; Li, Linzhi; Xiang, Jianhua; Gao, Guofu; Xu, Faxi; Liu, Ailing; Zhang, Xianwen; Peng, Yan; Chen, Xinbo; Wan, Xiangyuan

    2015-01-01

    Cuticular wax covers aerial organs of plants and functions as the outermost barrier against non-stomatal water loss. We reported here the functional characterization of the Glossy1(GL1)-homologous gene OsGL1-3 in rice using overexpression and RNAi transgenic rice plants. OsGL1-3 gene was ubiquitously expressed at different level in rice plants except root and its expression was up-regulated under ABA and PEG treatments. The transient expression of OsGL1-3–GFP fusion protein indicated that OsGL1-3 is mainly localized in the plasma membrane. Compared to the wild type, overexpression rice plants exhibited stunted growth, more wax crystallization on leaf surface, and significantly increased total cuticular wax load due to the prominent changes of C30–C32 aldehydes and C30 primary alcohols. While the RNAi knockdown mutant of OsGL1-3 exhibited no significant difference in plant height, but less wax crystallization and decreased total cuticular wax accumulation on leaf surface. All these evidences, together with the effects of OsGL1-3 on the expression of some wax synthesis related genes, suggest that OsGL1-3 is involved in cuticular wax biosynthesis. Overexpression of OsGL1-3 decreased chlorophyll leaching and water loss rate whereas increased tolerance to water deficit at both seedling and late-tillering stages, suggesting an important role of OsGL1-3 in drought tolerance. PMID:25555239

  15. OsHrd3 is necessary for maintaining the quality of endoplasmic reticulum-derived protein bodies in rice endosperm.

    PubMed

    Ohta, Masaru; Takaiwa, Fumio

    2015-08-01

    Large amounts of seed storage proteins (SSPs) are produced in the maturing endosperm of rice seeds. Rice SSPs are synthesized as secretory proteins on the rough endoplasmic reticulum (ER), and are transported and deposited into protein complexes called protein bodies (PB-I and PB-II). Due to the high production of SSPs, unfolded SSPs may be generated during this process. However, it was previously unclear how such unfolded proteins are selected among synthesized products and removed from the ER to maintain protein quality in the endosperm. Since Hrd3/SEL1L recognizes unfolded proteins in yeast and mammalian protein quality control systems, the role of OsHrd3 in protein quality control in rice endosperm was investigated. Co-immunoprecipitation experiments demonstrated that OsHrd3 interacts with components of the Hrd1 ubiquitin ligase complex such as OsOS-9 and OsHrd1 in rice protoplasts. Endosperm-specific suppression of OsHrd3 in transgenic rice reduced the levels of polyubiquitinated proteins and resulted in unfolded protein responses (UPRs) in the endosperm, suggesting that OsHrd3-mediated polyubiquitination plays an important role in ER quality control. It was found that a cysteine-rich 13kDa prolamin, RM1, was polyubiquitinated in wild-type (WT) seeds but not in OsHrd3 knockdown (KD) seeds. RM1 formed aberrant aggregates that were deposited abnormally in OsHrd3 KD seeds, resulting in deformed PB-I. Therefore, the quality of protein bodies is maintained by polyubiquitination of unfolded SSPs through the Hrd1 ubiquitin ligase system in rice endosperm. PMID:25977235

  16. OsHrd3 is necessary for maintaining the quality of endoplasmic reticulum-derived protein bodies in rice endosperm

    PubMed Central

    Ohta, Masaru; Takaiwa, Fumio

    2015-01-01

    Large amounts of seed storage proteins (SSPs) are produced in the maturing endosperm of rice seeds. Rice SSPs are synthesized as secretory proteins on the rough endoplasmic reticulum (ER), and are transported and deposited into protein complexes called protein bodies (PB-I and PB-II). Due to the high production of SSPs, unfolded SSPs may be generated during this process. However, it was previously unclear how such unfolded proteins are selected among synthesized products and removed from the ER to maintain protein quality in the endosperm. Since Hrd3/SEL1L recognizes unfolded proteins in yeast and mammalian protein quality control systems, the role of OsHrd3 in protein quality control in rice endosperm was investigated. Co-immunoprecipitation experiments demonstrated that OsHrd3 interacts with components of the Hrd1 ubiquitin ligase complex such as OsOS-9 and OsHrd1 in rice protoplasts. Endosperm-specific suppression of OsHrd3 in transgenic rice reduced the levels of polyubiquitinated proteins and resulted in unfolded protein responses (UPRs) in the endosperm, suggesting that OsHrd3-mediated polyubiquitination plays an important role in ER quality control. It was found that a cysteine-rich 13kDa prolamin, RM1, was polyubiquitinated in wild-type (WT) seeds but not in OsHrd3 knockdown (KD) seeds. RM1 formed aberrant aggregates that were deposited abnormally in OsHrd3 KD seeds, resulting in deformed PB-I. Therefore, the quality of protein bodies is maintained by polyubiquitination of unfolded SSPs through the Hrd1 ubiquitin ligase system in rice endosperm. PMID:25977235

  17. Overexpression of OsHMA3 enhances Cd tolerance and expression of Zn transporter genes in rice

    PubMed Central

    Sasaki, Akimasa; Yamaji, Naoki; Ma, Jian Feng

    2014-01-01

    As a member of the heavy metal ATPase (HMA) family, OsHMA3 is a tonoplast-localized transporter for Cd in the roots of rice (Oryza sativa). Overexpression of OsHMA3 selectively reduces Cd accumulation in the grain. Further characterization in the present study revealed that overexpression of OsHMA3 also enhances the tolerance to toxic Cd. The growth of both the roots and shoots was similar in the absence of Cd between an OsHMA3-overexpressed line and vector control, but the Cd-inhibited growth was significantly alleviated in the OsHMA3-overexpressed line. The overexpressed line showed higher Cd concentration in the roots, but lower Cd concentration in the shoots compared with the wild-type rice and vector control line, indicating that overexpression of OsHMA3 enhanced vacuolar sequestration of Cd in the roots. The Zn concentration in the roots of the OsHMA3-overexpressed line was constantly higher than that of vector control, but the Zn concentration in the shoots was similar between the overexpressed line and vector control. Five transporter genes belonging to the ZIP family were constitutively up-regulated in the OsHMA3-overexpressed line. These results suggest that shoot Zn level was maintained by up-regulating these genes involved in the Zn uptake/translocation. Taken together, overexpression of OsHMA3 is an efficient way to reduce Cd accumulation in the grain and to enhance Cd tolerance in rice. PMID:25151617

  18. Osmium Atoms and Os2 Molecules Move Faster on Selenium-Doped Compared to Sulfur-Doped Boronic Graphenic Surfaces

    PubMed Central

    2015-01-01

    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–1versus 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. PMID:26525180

  19. A key ABA catabolic gene, OsABA8ox3, is involved in drought stress resistance in rice.

    PubMed

    Cai, Shanlan; Jiang, Guobin; Ye, Nenghui; Chu, Zhizhan; Xu, Xuezhong; Zhang, Jianhua; Zhu, Guohui

    2015-01-01

    Expressions of ABA biosynthesis genes and catabolism genes are generally co-regulated in plant development and responses to environmental stress. Up-regulation of OsNCED3 gene, a key gene in ABA biosynthesis, has been suggested as a way to enhance plant drought resistance but little is known for the role of ABA catabolic genes during drought stress. In this study, we found that OsABA8ox3 was the most highly expressed gene of the OsABA8ox family in rice leaves. Expression of OsABA8ox3 was promptly induced by rehydration after PEG-mimic dehydration, a tendency opposite to the changes of ABA level. We therefore constructed rice OsABA8ox3 silencing (RNA interference, RNAi) and overexpression plants. There were no obvious phenotype differences between the transgenic seedlings and wild type under normal condition. However, OsABA8ox3 RNAi lines showed significant improvement in drought stress tolerance while the overexpression seedlings were hypersensitive to drought stress when compared with wild type in terms of plant survival rates after 10 days of unwatering. Enzyme activity analysis indicated that OsABA8ox3 RNAi plants had higher superoxide dismutase (SOD) and catalase (CAT) activities and less malondialdehyde (MDA) content than those of wild type when the plants were exposed to dehydration treatment, indicating a better anti-oxidative stress capability and less membrane damage. DNA microarray and real-time PCR analysis under dehydration treatment revealed that expressions of a group of stress/drought-related genes, i.e. LEA genes, were enhanced with higher transcript levels in OsABA8ox3 RNAi transgenic seedlings. We therefore conclude that that OsABA8ox3 gene plays an important role in controlling ABA level and drought stress resistance in rice. PMID:25647508

  20. A rare cause of foot pain with golf swing: symptomatic os vesalianum pedis-a case report.

    PubMed

    Petrera, Massimo; Dwyer, Tim; Ogilvie-Harris, Darrell J

    2013-07-01

    The os vesalianum is an uncommon accessory bone of the foot, located proximally to the base of the fifth metatarsal. It is usually asymptomatic and detected incidentally on radiographs. This is a case of bilateral os vesalianum, symptomatic only in the right foot, in a golf player. After a failed nonoperative treatment, the os vesalianum in the symptomatic foot was excised and the peroneus brevis tendon reattached using a suture anchor. The functional outcome was excellent, and the patient returned to golf 8 weeks after surgery. PMID:24459554

  1. 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

  2. Constitutive Expression of OsIAA9 Affects Starch Granules Accumulation and Root Gravitropic Response in Arabidopsis

    PubMed Central

    Luo, Sha; Li, Qianqian; Liu, Shanda; Pinas, Nicholaas M.; Tian, Hainan; Wang, Shucai

    2015-01-01

    Auxin/Indole-3-Acetic Acid (Aux/IAA) genes are early auxin response genes ecoding short-lived transcriptional repressors, which regulate auxin signaling in plants by interplay with Auxin Response Factors (ARFs). Most of the Aux/IAA proteins contain four different domains, namely Domain I, Domain II, Domain III, and Domain IV. So far all Aux/IAA mutants with auxin-related phenotypes identified in both Arabidopsis and rice (Oryza sativa) are dominant gain-of-function mutants with mutations in Domain II of the corresponding Aux/IAA proteins, suggest that Aux/IAA proteins in both Arabidopsis and rice are largely functional redundantly, and they may have conserved functions. We report here the functional characterization of a rice Aux/IAA gene, OsIAA9. RT-PCR results showed that expression of OsIAA9 was induced by exogenously applied auxin, suggesting that OsIAA9 is an auxin response gene. Bioinformatic analysis showed that OsIAA9 has a repressor motif in Domain I, a degron in Domain II, and the conserved amino acid signatures for protein-protein interactions in Domain III and Domain IV. By generating transgenic plants expressing GFP-OsIAA9 and examining florescence in the transgenic plants, we found that OsIAA9 is localized in the nucleus. When transfected into protoplasts isolated from rosette leaves of Arabidopsis, OsIAA9 repressed reporter gene expression, and the repression was partially released by exogenously IAA. These results suggest that OsIAA9 is a canonical Aux/IAA protein. Protoplast transfection assays showed that OsIAA9 interacted ARF5, but not ARF6, 7, 8 and 19. Transgenic Arabidopsis plants expressing OsIAA9 have increased number of lateral roots, and reduced gravitropic response. Further analysis showed that OsIAA9 transgenic Arabidopsis plants accumulated fewer granules in their root tips and the distribution of granules was also affected. Taken together, our study showed that OsIAA9 is a transcriptional repressor, and it regulates gravitropic

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

    NASA Astrophysics Data System (ADS)

    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 were characterized as an ordered double-perovskite structure of space group P21/n with the Ca and Os 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.

  4. Labilizing the Photoinert: Extraordinarily Facile Photochemical Ligand Ejection in an [Os(N^N)3 ](2+) Complex.

    PubMed

    Scattergood, Paul A; Ross, Daniel A W; Rice, Craig R; Elliott, Paul I P

    2016-08-26

    Whilst [Os(N^N)3 ](2+) complexes are supposed to be photochemically inert to ligand loss, the complex [Os(btz)3 ](2+) (btz=1,1'-dibenzyl-4,4'-bi-1,2,3-triazolyl) undergoes unprecedented photolytic reactivity to liberate free btz (Φ363 ≈1.2 %). Further, both cis and trans isomers of the photodechelated ligand-loss solvento intermediate [Os(κ(2) -btz)2 (κ(1) -btz)(NCMe)](2+) are unambiguously observed and characterized by NMR spectroscopy and mass spectrometry. PMID:27485699

  5. A calcium-binding protein, rice annexin OsANN1, enhances heat stress tolerance by modulating the production of H2O2.

    PubMed

    Qiao, Bei; Zhang, Qian; Liu, Dongliang; Wang, Haiqi; Yin, Jingya; Wang, Rui; He, Mengli; Cui, Meng; Shang, Zhonglin; Wang, Dekai; Zhu, Zhengge

    2015-09-01

    OsANN1 is a member of the annexin protein family in rice. The function of this protein and the mechanisms of its involvement in stress responses and stress tolerance are largely unknown. Here it is reported that OsANN1 confers abiotic stress tolerance by modulating antioxidant accumulation under abiotic stress. OsANN1-knockdown [RNA interference (RNAi)] plants were more sensitive to heat and drought stresses, whereas OsANN1-overexpression (OE) lines showed improved growth with higher expression of OsANN1 under abiotic stress. Overexpression of OsANN1 promoted SOD (superoxide dismutase) and CAT (catalase) activities, which regulate H2O2 content and redox homeostasis, suggesting the existence of a feedback mechanism between OsANN1 and H2O2 production under abiotic stress. Higher expression of OsANN1 can provide overall cellular protection against abiotic stress-induced damage, and a significant accumulation of OsANN1-green fluorescent protein (GFP) signals was found in the cytosol after heat shock treatment. OsANN1 also has calcium-binding and ATPase activities in vitro, indicating that OsANN1 has multiple functions in rice growth. Furthermore, yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays demonstrated that OsANN1 interacts with OsCDPK24. This cross-talk may provide additional layers of regulation in the abiotic stress response. PMID:26085678

  6. Insights into early Earth from the Pt-Re-Os isotope and highly siderophile element abundance systematics of Barberton komatiites

    NASA Astrophysics Data System (ADS)

    Puchtel, Igor S.; Walker, Richard J.; Touboul, Mathieu; Nisbet, Euan G.; Byerly, Gary R.

    2014-01-01

    Highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance and Pt-Re-Os isotopic data are reported for well-preserved komatiites from the Komati and Weltevreden Formations of the Barberton Greenstone Belt in South Africa. The Re-Os data for whole-rock samples and olivine and chromite separates define isochrons with ages of 3484 ± 38 and 3263 ± 12 Ma for the Komati and Weltevreden systems, respectively. The respective initial 187Os/188Os = 0.10335 ± 15 (γ187Os = +0.34 ± 0.15) and 0.10442 ± 4 (γ187Os = -0.14 ± 0.04) are well within the range defined by chondritic meteorites. When considered together with the Re-Os data for late Archean komatiite systems, these data indicate that the mantle sources of most Archean komatiites evolved with essentially uniform long-term Re/Os that is well within the chondritic range. By contrast, the initial 186Os/188Os = 0.1198283 ± 9 (ε186Os = -0.12 ± 0.08) and 0.1198330 ± 8 (ε186Os = +0.22 ± 0.07) for the Komati and Weltevreden systems, respectively, are outside of known chondritic evolution paths, indicating that the mantle sources of these two komatiite systems evolved with fractionated time-integrated Pt/Os. The new 186,187Os isotopic data for these early Archean komatiite systems, combined with published 142,143Nd and 176Hf isotopic data for these systems, are consistent with formation and long-term isolation of deep-seated mantle domains with fractionated time-integrated Sm/Nd, Lu/Hf, and Pt/Os ratios, at ca. 4400 Ma. These domains may have been generated as a result of late-stage crystallization of a primordial magma ocean involving Mg-perovskite, Ca-perovskite and Pt-alloys acting as the fractionating phases. The inferred fractionated mantle domains were sampled by the early Archean komatiites, but were largely mixed away by 2.7 Ga, as evidenced by uniform time-integrated Sm/Nd, Lu/Hf, and Pt/Os ratios inferred for the sources of most late Archean komatiite systems. The calculated total Pt + Pd

  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. Re Os isotope constraints on subcontinental lithospheric mantle evolution of southern South America

    NASA Astrophysics Data System (ADS)

    Schilling, Manuel Enrique; Carlson, Richard Walter; Conceição, Rommulo Vieira; Dantas, Celine; Bertotto, Gustavo Walter; Koester, Edinei

    2008-04-01

    We present Re-Os isotopic data for widely dispersed mantle xenoliths carried to the surface of southern South America (36°-52° S) by Eocene to recent alkaline magmatism. Our hypothesis is that the lithospheric mantle sections formed as the roots of southern South America reflect the history of crust formation and amalgamation at different periods of time and so present a complimentary picture of continent growth in South America by sampling deeper sections of continental lithosphere than provided by crustal rocks from the area. The Re-Os isotopic system gives unique chronological information about the time of mantle depletion that is associated with lithosphere formation. Our data show coherent model ages for the lithospheric mantle that can be correlated with some hypotheses for crustal evolution of this region. Most samples show Os isotopic values similar to the present suboceanic mantle, suggesting a relatively recent lithospheric mantle formation from the convecting mantle. Xenoliths from Agua Poca and Prahuaniyeu represent fragments of an ancient depleted lithosphere, probably corresponding to the roots of the Cuyania terrane inferred to be a fragment derived from Laurentia and formed during the Mesoproterozoic. Alternatively, all or parts of the recognized ancient lithosphere are relicts of other known ancient continental blocks, such as the Pampia terrane or the Río de la Plata craton. Samples erupted in the southwest corner of the Deseado Massif give Proterozoic depletion ages (1.34 to 2.11 Ga) that are considerably older than previous radiogenic formation ages obtained for the very few basements rocks of this continental block. We propose that Deseado Massif is Proterozoic in age, probably related to the Malvinas/Falkland Islands and plateau and so should be considered for the reconstruction of the supercontinent of Rodinia.

  10. Interactions between an injected polydnavirus and per os baculovirus in gypsy moth larvae.

    PubMed

    D'Amico, V; Podgwaite, J D; Zerillo, R; Taylor, P; Fuester, R

    2013-10-01

    Larval gypsy moths, Lymantria dispar (Lepidoptera:Lymantriidae) were co-infected with the L. dispar nucleopolyhedrovirus (LdMNPV) and the Cotesia melanoscela (Hymenoptera:Braconidae) polydnavirus (CmeBV). CmeBV was given along with a parasitoid egg and calyx products in a stinging event, or in the form of an injection of calyx-derived extract. LdMNPV was delivered per os, integrated into artificial diet. Mortality from all sources was recorded over the subsequent three-week period. Neither parasitism nor injections of purified CmeBV with toxin had any effect on the amount of mortality caused by concurrent challenges with LdMNPV. PMID:23933012

  11. Successful treatment of paraquat poisoning: activated charcoal per os and "continuous hemoperfusion".

    PubMed

    Okonek, S; Weilemann, L S; Majdandzic, J; Setyadharma, H; Reinecke, H J; Baldamus, C A; Lohmann, J; Bonzel, K E; Thon, T

    1982-10-01

    Ingestion of paraquat results in an extremely dangerous poisoning. The first aim is to clear the gastrointestinal tract by inducing emesis and performing gastric/gut lavage; as much activated charcoal as possible should be administered per os and as quickly as possible. The best measure to eliminate paraquat from blood and tissue is hemoperfusion with coated activated charcoal; it has to be performed in the sense of "continuous hemoperfusion" about 8 h/d over a period of 2-3 weeks. These measures give a chance to lower the lethality of paraquat poisoning. PMID:7182509

  12. 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.

  13. Semi-phenomenological description of the chiral bands in 188,190Os

    NASA Astrophysics Data System (ADS)

    Raduta, A. A.; Raduta, C. M.

    2015-06-01

    A set of interacting particles are coupled to a phenomenological core described using the generalized coherent state model. Among the particle-core states, a finite set which have the property that the angular momenta carried by the proton and neutron quadrupole bosons and the particles, separately, are mutually orthogonal are identified. The magnetic properties of such states are studied. All terms of the model Hamiltonian exhibit chiral symmetry except the spin-spin interaction one. There are four bands of the type with two-quasiparticle-core dipole states, exhibiting properties which are specific to magnetic twin bands. An application is presented, for the isotopes 188,190Os.

  14. Was Anna O.'s black snake hallucination a sleep paralysis nightmare? Dreams, memories, and trauma.

    PubMed

    Powell, R A; Nielsen, T A

    1998-01-01

    The final traumatic event recalled by Anna O. during her treatment with Josef Breuer was a terrifying hallucination she once had of a black snake attacking her ailing father. This event has been variously interpreted as indicating an underlying psychodynamic conflict, as a temporal lobe seizure, and as an hypnotic confabulation. We argue, however, that the hallucination--during which Anna O.'s arm was reportedly "asleep" due to nerve blockage--was probably a sleep paralysis nightmare. Sleep paralysis nightmares continue to be overlooked or misdiagnosed in clinical practice, and, in recent years, have been implicated in the controversy surrounding memories of trauma and sexual abuse. PMID:9823033

  15. 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. PMID:16495689

  16. 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.

  17. High-pressure synthesis, crystal structure, and magnetic properties of KSbO3-type 5d oxides K0.84OsO3 and Bi2.93Os3O11

    NASA Astrophysics Data System (ADS)

    Yuan, Yahua; Feng, Hai L.; Shi, Youguo; Tsujimoto, Yoshihiro; Belik, Alexei A.; Matsushita, Yoshitaka; Arai, Masao; He, Jianfeng; Tanaka, Masahiko; Yamaura, Kazunari

    2014-12-01

    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).

  18. 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

  19. Solution preparation of the amorphous molybdenum oxysulfide MoOS{sub 2} and its use for catalysis

    SciTech Connect

    Genuit, Daisy; Bezverkhyy, Igor; Afanasiev, Pavel . E-mail: afanas@catalyse.univ-lyon1.fr

    2005-09-15

    Acid condensation of aqueous MoO{sub 2}S{sub 2} {sup 2-} anion yields amorphous MoOS{sub 2} oxysulfide. This compound possesses tubular morphology and when freshly precipitated is soluble in polar organics such as acetone and ethanol. The ensemble of characterizations (IR, UV-visible, EXAFS spectroscopy) suggests that it contains cyclic or short linear oligomers of neutral molybdenum (V) oxysulfide MoOS{sub 2} core. Thermal decomposition of MoOS{sub 2} under inert atmosphere leads to the formation of a mixture of MoO{sub 2} and MoS{sub 2} phases. Promotion of MoOS{sub 2} with cobalt followed by sulfidation leads to highly active HDS catalysts.

  20. Overexpression of Rice Wall-Associated Kinase 25 (OsWAK25) Alters Resistance to Bacterial and Fungal Pathogens.

    PubMed

    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

  1. 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

    2014-01-01

    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. PMID:24938613

  2. 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

  3. GPS, punto de contacto entre la Astronomía y otras disciplinas

    NASA Astrophysics Data System (ADS)

    Perdomo, R.

    En los primeros años de la pasada década, un grupo de Astrónomos de La Plata iniciaron trabajos de investigación en Geodesia Satelital. En esta presentación se propone repasar sus principales logros y situarlos en el contexto del desarrollo de la disciplina a nivel mundial. Por entonces las aplicaciones prácticas de la disciplina eran indirectas y solo evidentes para los especialistas. Los errores del Posicionamiento Satelital eran de varios metros y en posicionamiento relativo, del orden de medio metro. Estos resultados se lograban al cabo de varios días de medición continuada. En los años siguientes, el sistema GPS alcanzó su nivel operacional y produjo una revolución tanto en lo relacionado con los tiempos de medición como con las precisiones. El grupo de La Plata se desarrolló simultáneamente con GPS, lo que posibilitó su participación actual en diversos temas vigentes: aplicaciones de alta precisión para la materialización de sistemas terrestres de referencia, monitoreo de movimientos de la corteza, contribución con servicios internacionales para la determinación de movimientos tectónicos globales y regionales, monitoreo de la ionósfera a partir de la propagación de las señales, determinación de la ondulación del geoide a escala local, etc. También se generaron muchas aplicaciones prácticas algunas en tiempo real: navegación, apoyo a imágenes aéreas o satelitales, aplicaciones a la agricultura, catastro y ordenamiento territorial, apoyo a relevamientos geofísicos, etc.

  4. slc7a6os Gene Plays a Critical Role in Defined Areas of the Developing CNS in Zebrafish

    PubMed Central

    Benini, Anna; Cignarella, Francesca; Calvarini, Laura; Mantovanelli, Silvia; Giacopuzzi, Edoardo; Zizioli, Daniela; Borsani, Giuseppe

    2015-01-01

    The aim of this study is to shed light on the functional role of slc7a6os, a gene highly conserved in vertebrates. The Danio rerio slc7a6os gene encodes a protein of 326 amino acids with 46% identity to human SLC7A6OS and 14% to Saccharomyces cerevisiae polypeptide Iwr1. Yeast Iwr1 specifically binds RNA pol II, interacts with the basal transcription machinery and regulates the transcription of specific genes. In this study we investigated for the first time the biological role of SLC7A6OS in vertebrates. Zebrafish slc7a6os is a maternal gene that is expressed throughout development, with a prevalent localization in the developing central nervous system (CNS). The gene is also expressed, although at different levels, in various tissues of the adult fish. To determine the functional role of slc7a6os during zebrafish development, we knocked-down the gene by injecting a splice-blocking morpholino. At 24 hpf morphants show morphological defects in the CNS, particularly the interface between hindbrain and midbrain is not well-defined. At 28 hpf the morpholino injected embryos present an altered somite morphology and appear partially or completely immotile. At this stage the midbrain, hindbrain and cerebellum are compromised and not well defined compared with control embryos. The observed alterations persist at later developmental stages. Consistently, the expression pattern of two markers specifically expressed in the developing CNS, pax2a and neurod, is significantly altered in morphants. The co-injection of embryos with synthetic slc7a6os mRNA, rescues the morphant phenotype and restores the wild type expression pattern of pax2a and neurod. Our data suggest that slc7a6os might play a critical role in defined areas of the developing CNS in vertebrates, probably by regulating the expression of key genes. PMID:25803583

  5. 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. PMID:26366992

  6. Spirobifluorene bridged Ir(III) and Os(II) polypyridyl arrays: synthesis, photophysical characterization, and energy transfer dynamics.

    PubMed

    Ventura, Barbara; Barbieri, Andrea; Degli Esposti, Alessandra; Seneclauze, Julie Batcha; Ziessel, Raymond

    2012-03-01

    The synthesis, characterization, photophysics, and time-dependent density functional theory (TD-DFT) calculations of spirobifluorene-bipyridine based iridium(III), osmium(II), and mixed Ir/Os complexes are presented. The preparation of the reference and mixed complexes proceeded step-by-step and microwave irradiation facilitated the complexation of osmium. The absorption of the target heterobimetallic derivative, Ir-L-Os, is described by linear combination of half of the absorption spectra of the homobimetallic analogues, Ir-L-Ir and Os-L-Os, due to the occurrence of mixed ligand and metal based transitions when the spirobifluorene-(bpy)(2) bridging ligand L is linked to the metal, confirming a negligible interaction between the substituted metallic chromophores. TD-DFT calculations on monometallic, homo- and hetero-bimetallic complexes fully disentangled the origin of the absorption features. Noticeably, in the mixed Ir-L-Os complex an almost quantitative energy transfer from the (3)Ir to the (3)Os MLCT state is occurring, with a rate constant of 4.1 × 10(8) s(-1) and nearly exclusively via a Dexter-type mechanism mediated by the orbitals of the spiroconjugated ligand. This result, together with the outcomes of the TD-DFT calculations, supports the existence of spiroconjugation and evidences the interesting role of this kind of bridge in the energy transfer dynamics of the arrays. In all the complexes, moreover, the ligand fluorescence is heavily quenched by energy transfer processes toward the metallic appended units; the rate constant is estimated in the order of 10(10) s(-1) for Ir-L-Os and higher than 10(12) s(-1) for the other complexes. In the heterometallic array, both at room temperature and at 77 K, all photons are thus funneled to the emissive Os (3)MLCT state, which acts as energy trap for the antenna cascade. PMID:22356478

  7. Over-Expression of Rice CBS Domain Containing Protein, OsCBSX3, Confers Rice Resistance to Magnaporthe oryzae Inoculation.

    PubMed

    Mou, Shaoliang; Shi, Lanping; Lin, Wei; Liu, Yanyan; Shen, Lei; Guan, Deyi; He, Shuilin

    2015-01-01

    Cystathionine β-synthase (CBS) domain containing proteins (CDCPs) constitute a big family in plants and some members in this family have been implicated in a variety of biological processes, but the precise functions and the underlying mechanism of the majority of this family in plant immunity remain to be elucidated. In the present study, a CBS domain containing protein gene, OsCBSX3, is functionally characterized in rice resistance against Magnaporthe oryzae (M. oryzae). By quantitative real-time PCR, transcripts of OsCBSX3 are up-regulated significantly by inoculation of M. oryzae and the exogenously applied salicylic acid (SA) and methyl jasmonate (MeJA). OsCBSX3 is exclusively localized to the plasma membrane by transient expression of OsCBSX3 fused to green fluorescent protein (GFP) through approach of Agrobacterium infiltration in Nicotiana benthamiana leaves. The plants of homozygous T3 transgenic rice lines of over-expressing OsCBSX3 exhibit significant enhanced resistance to M. oryzae inoculation, manifested by decreased disease symptoms, and inhibition of pathogen growth detected in DNA. Consistently, the over-expression of OsCBSX3 enhances the transcript levels of immunity associated marker genes including PR1a, PR1b, PR5, AOS2, PAL, NH1, and OsWRKY13 in plants inoculated with M. oryzae. These results suggest that OsCBSX3 acts as a positive regulator in resistance of rice to M. oryzae regulated by SA and JA-mediated signaling pathways synergistically. PMID:26184180

  8. Over-Expression of Rice CBS Domain Containing Protein, OsCBSX3, Confers Rice Resistance to Magnaporthe oryzae Inoculation

    PubMed Central

    Mou, Shaoliang; Shi, Lanping; Lin, Wei; Liu, Yanyan; Shen, Lei; Guan, Deyi; He, Shuilin

    2015-01-01

    Cystathionine β-synthase (CBS) domain containing proteins (CDCPs) constitute a big family in plants and some members in this family have been implicated in a variety of biological processes, but the precise functions and the underlying mechanism of the majority of this family in plant immunity remain to be elucidated. In the present study, a CBS domain containing protein gene, OsCBSX3, is functionally characterized in rice resistance against Magnaporthe oryzae (M. oryzae). By quantitative real-time PCR, transcripts of OsCBSX3 are up-regulated significantly by inoculation of M. oryzae and the exogenously applied salicylic acid (SA) and methyl jasmonate (MeJA). OsCBSX3 is exclusively localized to the plasma membrane by transient expression of OsCBSX3 fused to green fluorescent protein (GFP) through approach of Agrobacterium infiltration in Nicotiana benthamiana leaves. The plants of homozygous T3 transgenic rice lines of over-expressing OsCBSX3 exhibit significant enhanced resistance to M. oryzae inoculation, manifested by decreased disease symptoms, and inhibition of pathogen growth detected in DNA. Consistently, the over-expression of OsCBSX3 enhances the transcript levels of immunity associated marker genes including PR1a, PR1b, PR5, AOS2, PAL, NH1, and OsWRKY13 in plants inoculated with M. oryzae. These results suggest that OsCBSX3 acts as a positive regulator in resistance of rice to M. oryzae regulated by SA and JA-mediated signaling pathways synergistically. PMID:26184180

  9. A neutron scattering study of the crystal and magnetic structure of Sr2CrOsO6

    NASA Astrophysics Data System (ADS)

    Krockenberger, Y.; Reehuis, M.; Tovar, M.; Mogare, K.; Jansen, M.; Alff, L.

    2007-03-01

    Recently, the new osmium-based ferrimagnetic double perovskite Sr2CrOsO6 has been reported to have the highest Curie temperature (˜725 K) within this material class [Y. Krockenberger, K. Mogare, M. Reehuis, M. Tovar, M. Jansen, G. Vaitheeswaran, V. Kanchana, A. Delin, F. Wilhelm, A. Rogalev, A. Winkler, L. Alff, preprint, 2006]. Here, we report details about the crystal and magnetic structure of Sr2CrOsO6 as obtained by neutron powder diffraction.

  10. Re-Os Systematics on Metallic Materials of Meteorites: Evidence for Non-Magmatic Evolution of the Iron Meteorites

    NASA Astrophysics Data System (ADS)

    Hirata, T.; Masuda, A.

    1992-07-01

    The ^187Re-^187Os isotopic pair can offer piercing chemical and chronological information for the early sequences of the solar system [1,2]. Its principal interest over the other chronometer stands not only in siderophilic nature, but also in highly refractory physicochemical characteristics of both Re and Os. Although the progress of Re-Os chronometer has been retarded by the difficulty in Os isotopic analysis, recent developments in a variety of mass spectrometry have enabled us to give easier access to the Os isotopic measurement with high sensitivity. We have analyzed Re and Os abundances in 12 iron meteorites of various groups and 5 stony iron meteorites by stable isotope dilution employing an enhanced sensitivity inductively coupled plasma mass spectrometry [3,4]. In Fig. 1 we show the Re vs. Os abundance plot for the iron and stony iron meteorites obtained. Present Re and Os abundance data indicate some important features that can contribute to the elucidation of the evolutional history of these metallic meteorites. 1. Re and Os abundances in iron and stony iron meteorites have a wide variation covering nearly four orders of magnitude. 2. In contrast, there is no significant change in abundance ratio of Re/Os. The relationship between the Re and Os abundances gives a correlation coefficient of 0.996. 3. The group with the highest Re and Os abundances are the iron meteorites of group IVB [5,6]. 4. Sikhote-Alin (IIB-Anom) has exceptionally low Re and Os abundance values compared with those for other iron meteorites, but fall on the regression line drawn by other meteorites. 5. The Re and Os abundances in pallasite stony iron meteorites (circles on Fig. 1) show extremely low values compared with those for most iron meteorites. 6. The Re and Os abundances in mesosiderite stony iron meteorites (squares on Fig. 1) show values comparable with those observed in most iron meteorites. Fig. 2 shows the abundance relationship between Ir and Os (Ir data were taken from

  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. 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. PMID:24723395

  13. Magnetic structure of the quasi-one-dimensional La3OsO7 as determined by neutron powder diffraction

    DOE PAGESBeta

    Morrow, Ryan; Susner, Michael A.; Sumption, Michael D.; Woodward, Patrick M.

    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.

  14. 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

  15. Shape evolution in the neutron-rich osmium isotopes: Prompt γ-ray spectroscopy of Os196

    NASA Astrophysics Data System (ADS)

    John, P. R.; Modamio, V.; Valiente-Dobón, J. J.; Mengoni, D.; Lunardi, S.; Rodríguez, T. R.; Bazzacco, D.; Gadea, A.; Wheldon, C.; Alexander, T.; de Angelis, G.; Ashwood, N.; Barr, M.; Benzoni, G.; Birkenbach, B.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; Bottoni, S.; Bowry, M.; Bracco, A.; Browne, F.; Bunce, M.; Camera, F.; Cederwall, B.; Corradi, L.; Crespi, F. C. L.; Désesquelles, P.; Eberth, J.; Farnea, E.; Fioretto, E.; Görgen, A.; Gottardo, A.; Grebosz, J.; Grente, L.; Hess, H.; Jungclaus, A.; Kokalova, Tz.; Korichi, A.; Korten, W.; Kuşoǧlu, A.; Lenzi, S.; Leoni, S.; Ljungvall, J.; Maron, G.; Meczynski, W.; Melon, B.; Menegazzo, R.; Michelagnoli, C.; Mijatović, T.; Million, B.; Molini, P.; Montagnoli, G.; Montanari, D.; Napoli, D. R.; Nolan, P.; Oziol, Ch.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Roberts, O. J.; Rosso, D.; Şahin, E.; Salsac, M.-D.; Scarlassara, F.; Sferrazza, M.; Simpson, J.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Theisen, Ch.; Ur, C. A.; Walshe, J.

    2014-08-01

    The shape transition in the neutron-rich Os isotopes is studied by investigating the neutron-rich 196Os nucleus through in-beam γ-ray spectroscopy using a two-proton transfer reaction from a 198Pt target to a 82Se beam. The beam-like recoils were detected and identified with the large-acceptance magnetic spectrometer PRISMA, and the coincident γ rays were measured with the advanced gamma tracking array (AGATA) demonstrator. The de-excitation of the low-lying levels of the yrast-band of 196Os were identified for the first time. The results are compared with state-of-the-art beyond-mean-field calculations, performed for the even-even 188-198Os isotopes. The new results suggest a smooth transition in the Os isotopes from a more axial rotational behavior towards predominately vibrational nuclei through triaxial configurations. An almost perfect γ-unstable/triaxial rotor yrast band is predicted for 196Os which is in agreement with the experimentally measured excited states.

  16. Identification of Fatty Acid Glucose Esters as Os9BGlu31 Transglucosidase Substrates in Rice Flag Leaves.

    PubMed

    Komvongsa, Juthamath; Mahong, Bancha; Phasai, Kannika; Hua, Yanling; Jeon, Jong-Seong; Ketudat Cairns, James R

    2015-11-11

    Rice Os9BGlu31 transglucosidase transfers glucosyl moieties between various carboxylic acids and alcohols, including phenolic acids and flavonoids, in vitro. The role of Os9BGlu31 transglucosidase in rice plant metabolism has only been suggested to date. Methanolic extracts of rice bran and leaves were found to contain oleic acid and linoleic acid to which Os9BGlu31 could transfer glucose from the 4-nitrophenyl β-D-glucoside (4NPGlc) donor to form 1-O-acyl glucose esters. Os9BGlu31 showed higher activity with oleic acid (18:1) and linoleic acid (18:2) than with stearic acid (18:0) and had both a higher kcat and a higher Km for linoleic than oleic acid in the presence of 8 mM 4NPGlc donor. Os9BGlu31 knockout mutant rice lines were found to have significantly larger amounts of fatty acid glucose esters than wild-type control lines. Because the transglucosylation reaction is reversible, these data suggest that fatty acid glucose esters act as glucosyl donor substrates for Os9BGlu31 transglucosidase in rice. PMID:26477245

  17. OsHSD1, a hydroxysteroid dehydrogenase, is involved in cuticle formation and lipid homeostasis in rice.

    PubMed

    Zhang, Zhe; Cheng, Zhi-Jun; Gan, Lu; Zhang, Huan; Wu, Fu-Qing; Lin, Qi-Bing; Wang, Jiu-Lin; Wang, Jie; Guo, Xiu-Ping; Zhang, Xin; Zhao, Zhi-Chao; Lei, Cai-Lin; Zhu, Shan-Shan; Wang, Chun-Ming; Wan, Jian-Min

    2016-08-01

    Cuticular wax, a hydrophobic layer on the surface of all aerial plant organs, has essential roles in plant growth and survival under various environments. Here we report a wax-deficient rice mutant oshsd1 with reduced epicuticular wax crystals and thicker cuticle membrane. Quantification of the wax components and fatty acids showed elevated levels of very-long-chain fatty acids (VLCFAs) and accumulation of soluble fatty acids in the leaves of the oshsd1 mutant. We determined the causative gene OsHSD1, a member of the short-chain dehydrogenase reductase family, through map-based cloning. It was ubiquitously expressed and responded to cold stress and exogenous treatments with NaCl or brassinosteroid analogs. Transient expression of OsHSD1-tagged green fluorescent protein revealed that OsHSD1 localized to both oil bodies and endoplasmic reticulum (ER). Dehydrogenase activity assays demonstrated that OsHSD1 was an NAD(+)/NADP(+)-dependent sterol dehydrogenase. Furthermore, OsHSD1 mutation resulted in faster protein degradation, but had no effect on the dehydrogenase activity. Together, our data indicated that OsHSD1 plays a specialized role in cuticle formation and lipid homeostasis, probably by mediating sterol signaling. This work provides new insights into oil-body associated proteins involved in wax and lipid metabolism. PMID:27297988

  18. 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

  19. OsCYP21-4, a novel Golgi-resident cyclophilin, increases oxidative stress tolerance in rice.

    PubMed

    Lee, Sang S; Park, Hyun J; Jung, Won Y; Lee, Areum; Yoon, Dae H; You, Young N; Kim, Hyun-Soon; Kim, Beom-Gi; Ahn, Jun C; Cho, Hye S

    2015-01-01

    OsCYP21-4 is a rice cyclophilin protein that binds to cyclosporine A, an immunosuppressant drug. CYP21-4s in Arabidopsis and rice were previously shown to function as mitochondrial cyclophilins, as determined by TargetP analysis. In the current study, we found that OsCYP21-4-GFP localized to the Golgi, rather than mitochondria, in Nicotiana benthamiana leaves, which was confirmed based on its co-localization with cis Golgi α-ManI-mCherry protein. OsCYP21-4 transcript levels increased in response to treatments with various abiotic stresses and the phytohormone abscisic acid, revealing its stress-responsiveness. CYP21-4 homologs do not possess key peptidyl prolyl cis/trans isomerase (PPIase) activity/cyclosporine A (CsA) binding residues, and recombinant OsCYP21-4 protein did not convert the synthetic substrate Suc-AAPF-pNA via cis- trans- isomerization in vitro. In addition, transgenic plants overexpressing OsCYP21-4 exhibited increased tolerance to salinity and hydrogen peroxide treatment, along with increased peroxidase activity. These results demonstrate that OsCYP21-4 is a novel Golgi-localized cyclophilin that plays a role in oxidative stress tolerance, possibly by regulating peroxidase activity. PMID:26483814

  20. Pressure-induced structural transition of OsN2 and effect of metallic bonding on its hardness

    NASA Astrophysics Data System (ADS)

    Wang, Zhen-Hua; Kuang, Xiao-Yu; Zhong, Ming-Min; Lu, Peng; Mao, Ai-Jie; Huang, Xiao-Fen

    2011-09-01

    Using first-principles calculations, the elastic constant, structural phase transition and effect of metallic bonding on the hardness of OsN2 under high pressure are investigated by means of the pseudopotential plane-waves method. Five candidate structures are chosen to investigate for OsN2, namely, the pyrite, CoSb2-type, marcasite, simple hexagonal and tetragonal structures. A comparison among the formation energies of OsN2 explains the synthesis of OsN2 marcasite under high pressure. On the basis of the third-order Birch-Murnaghan equation of states, the transition pressure Pt (Pt=223 GPa) between the marcasite and simple tetragonal phase is determinated. Elastic constants, shear modulus, Young's modulus, Poisson's ratio and Debye temperature are derived. The calculated values are, generally speaking, in good agreement with experiments and other theoretical calculations. Our calculation indicates that the N-N bond length is one determinative factor for the ultrahigh bulk moduli of the heavy-transition-metal dinitrides. Moreover, based on Mulliken overlap population analysis in first-principles technique, a semiempirical method to evaluate the hardness of multicomponent crystals with partial metallic bonding is presented. The effect of metallic bonding on the hardness of OsN2 is investigated and the hardness shows a gradual decrease rather than increase under compression, which is different from diamond. This is a quantitative investigation on the structural properties of OsN2, and it still awaits experimental confirmation.

  1. Crystal growth and characterization of the narrow-band-gap semiconductors OsPn₂ (Pn = P, As, Sb).

    PubMed

    Bugaris, Daniel E; Malliakas, Christos D; Shoemaker, Daniel P; Do, Dat T; Chung, Duck Young; Mahanti, Subhendra D; Kanatzidis, Mercouri G

    2014-09-15

    Using metal fluxes, crystals of the binary osmium dipnictides OsPn2 (Pn = P, As, Sb) have been grown for the first time. Single-crystal X-ray diffraction confirms that these compounds crystallize in the marcasite structure type with orthorhombic space group Pnnm. The structure is a three-dimensional framework of corner- and edge-sharing OsPn6 octahedra, as well as [Pn2(4-)] anions. Raman spectroscopy shows the presence of P-P single bonds, consistent with the presence of [Pn2(-4)] anions and formally Os(4+) cations. Optical-band-gap and high-temperature electrical resistivity measurements indicate that these materials are narrow-band-gap semiconductors. The experimentally determined Seebeck coefficients reveal that nominally undoped OsP2 and OsSb2 are n-type semiconductors, whereas OsAs2 is p-type. Electronic band structure using density functional theory calculations shows that these compounds are indirect narrow-band-gap semiconductors. The bonding p orbitals associated with the Pn2 dimer are below the Fermi energy, and the corresponding antibonding states are above, consistent with a Pn-Pn single bond. Thermopower calculations using Boltzmann transport theory and constant relaxation time approximation show that these materials are potentially good thermoelectrics, in agreement with experiment. PMID:25162930

  2. OsCYP21-4, a novel Golgi-resident cyclophilin, increases oxidative stress tolerance in rice

    PubMed Central

    Lee, Sang S.; Park, Hyun J.; Jung, Won Y.; Lee, Areum; Yoon, Dae H.; You, Young N.; Kim, Hyun-Soon; Kim, Beom-Gi; Ahn, Jun C.; Cho, Hye S.

    2015-01-01

    OsCYP21-4 is a rice cyclophilin protein that binds to cyclosporine A, an immunosuppressant drug. CYP21-4s in Arabidopsis and rice were previously shown to function as mitochondrial cyclophilins, as determined by TargetP analysis. In the current study, we found that OsCYP21-4-GFP localized to the Golgi, rather than mitochondria, in Nicotiana benthamiana leaves, which was confirmed based on its co-localization with cis Golgi α-ManI-mCherry protein. OsCYP21-4 transcript levels increased in response to treatments with various abiotic stresses and the phytohormone abscisic acid, revealing its stress-responsiveness. CYP21-4 homologs do not possess key peptidyl prolyl cis/trans isomerase (PPIase) activity/cyclosporine A (CsA) binding residues, and recombinant OsCYP21-4 protein did not convert the synthetic substrate Suc-AAPF-pNA via cis- trans- isomerization in vitro. In addition, transgenic plants overexpressing OsCYP21-4 exhibited increased tolerance to salinity and hydrogen peroxide treatment, along with increased peroxidase activity. These results demonstrate that OsCYP21-4 is a novel Golgi-localized cyclophilin that plays a role in oxidative stress tolerance, possibly by regulating peroxidase activity. PMID:26483814

  3. Rice nitrate transporter OsNPF2.4 functions in low-affinity acquisition and long-distance transport.

    PubMed

    Xia, Xiudong; Fan, Xiaorong; Wei, Jia; Feng, Huimin; Qu, Hongye; Xie, Dan; Miller, Anthony J; Xu, Guohua

    2015-01-01

    Plant proteins belonging to the NPF (formerly NRT1/PTR) family are well represented in every genome and function in transporting a wide variety of substrates. In this study, we showed that rice OsNPF2.4 is located in the plasma membrane and is expressed mainly in the epidermis, xylem parenchyma, and phloem companion cells. Functional analysis in oocytes showed that OsNPF2.4 is a pH-dependent, low-affinity NO₃⁻ transporter. Short-term (¹⁵NO₃⁻) influx rate, long-term NO₃⁻ acquisition by root, and upward transfer from root to shoot were decreased by disruption of OsNPF2.4 and increased by OsNPF2.4 overexpression under high NO₃⁻ supply. Moreover, the redistribution of NO₃⁻ in the mutants in comparison with the wild type from the oldest leaf to other organs, particularly to N-starved roots, was dramatically changed. Knockout of OsNPF2.4 decreased rice growth and potassium (K) concentration in xylem sap, root, culm, and sheath, but increased the shoot:root ratio of tissue K under higher NO₃⁻. We conclude that OsNPF2.4 functions in acquisition and long-distance transport of NO₃⁻ , and that altering its expression has an indirect effect on K recycling between the root and shoot. PMID:25332358

  4. Mutation of Rice Early Flowering3.1 (OsELF3.1) delays leaf senescence in rice.

    PubMed

    Sakuraba, Yasuhito; Han, Su-Hyun; Yang, Hyun-Jung; Piao, Weilan; Paek, Nam-Chon

    2016-09-01

    In Arabidopsis, EARLY FLOWERING3 (ELF3) has pivotal roles in controlling circadian rhythm and photoperiodic flowering. In addition, ELF3 negatively regulates leaf senescence by repressing the transcription of PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PHYTOCHROME-INTERACTING FACTOR5 (PIF5); elf3 mutants senesce earlier and ELF3-overexpressing (ELF3-OX) plants senesce later than wild type (WT). Here, we show that in contrast to Arabidopsis ELF3, which represses senescence, the rice homolog OsELF3.1 promotes leaf senescence; oself3.1 mutants showed delayed senescence and OsELF3.1-OX plants senesced earlier under both dark-induced and natural senescence conditions. Microarray analysis revealed that in the senescing leaves, a number of senescence-associated genes, phytohormone-related genes, and NAC and WRKY family genes (OsNAP, ONAC106, and OsWRKY42) were differentially expressed in oself3.1 mutants compared with WT. Interestingly, we found that Arabidopsis plants overexpressing OsELF3.1 show delayed leaf senescence, produce short petioles, and flower late in long days, just like Arabidopsis ELF3-OX plants. This demonstrates that the regulatory functions of ELF3 and OsELF3.1 are conserved between Arabidopsis and rice, but the downstream regulatory cascades have opposite effects. PMID:27380315

  5. Combined Whole-Rock to Nano-Scale Investigations Reveal Contrasting Response of Pt-Os and Re-Os Isotope Systematics During Magmatic and Post-Magmatic Processes

    NASA Astrophysics Data System (ADS)

    Coggon, J. A.; Luguet, A.; Lorand, J. P.; Fonseca, R.; Wainwright, A.; Appel, P.; Hoffmann, J. E.; Nowell, G. M.

    2015-12-01

    Advances in single-grain and micro- and nano-analytical techniques in recent years have been particularly important to the study of highly siderophile elements (HSE) and have contributed significantly to our knowledge and understanding of their host phases and behaviour. Furthermore, whole-rock- to nano-scale studies provide new perspectives for investigation of HSE isotope systematics. Recent multi-scale 187Re-187Os and 190Pt-186Os studies facilitate comparison, to a previously unattainable degree, of the differing responses of these two decay systems to magmatic and post-magmatic processes. It is well established that mafic-ultramafic melts are sensitive to disturbance of their Re-Os isotope systematics by crustal assimilation, due to the incompatibility and resulting enrichment of Re in crustal lithologies. In contrast the very long half-life and extremely low atomic abundance of 190Pt, combined with relatively low Pt concentrations in crustal rocks, generally render the Pt-Os isotope system insensitive to modification during assimilation. However, using new single chromite grain data (Coggon et al., 2015) from the >3.811 Ga Ujaragssuit nunât layered ultramafic body, Greenland, we show that it is possible to distinguish two distinct episodes of 187Os/188Os modification; Country rock contamination of the parent melt was followed by later metamorphic disturbance of the isotope system. The Pt-Os data (Coggon et al., 2013) from the same samples show no evidence of crustal assimilation, but preserve signatures of mantle melting at ~4.1 Ga as well as disturbance during metamorphism. Macro- to micro-petrographic study clearly demonstrates that Pt, Re and Os are hosted by different mineral phases, of different origins, in these samples. This, together with the physical parameters of the decay systems reported above, leads to the dissimilar behaviour and response of the 187Re-187Os and 190Pt-186Os isotope systems during both magmatic and post-magmatic processes and

  6. The Autographa californica multiple nucleopolyhedrovirus ac110 gene encodes a new per os infectivity factor.

    PubMed

    Jiantao Liu; Zhu, Leyuan; Zhang, Shan; Deng, Zihao; Huang, Zhihong; Yuan, Meijin; Wu, Wenbi; Yang, Kai

    2016-08-01

    The Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac110 gene is especially conserved in lepidopteran-specific baculoviruses and is uncharacterized. To investigate the role of ac110 in the baculovirus life cycle, an ac110-knockout (vAc110KO) and a repair (vAc110:HA) viruses were constructed in this study. Budded virion production and occlusion body formation were unaffected in vAc110KO-transfected or infected Sf9 cells. Intrahemocoelic injection of budded virions of vAc110KO killed Trichoplusia ni larvae as efficiently as the repair or the wild-type viruses. However, per os inoculation of occlusion bodies of vAc110KO failed to establish infection in T. ni larvae, while the repair virus was as efficient as the wild-type virus. Treatment with calcofluor white, a reagent that damages the peritrophic membrane, did not rescue the oral infectivity of vAc110KO. These results suggested that Ac110 is a new per os infectivity factor that may play a role after occlusion-derived virions pass through the peritrophic membrane during oral infection. PMID:27212681

  7. Ionization and photofragmentation of Ru3(CO)12 and Os3(CO)12.

    PubMed

    Schalk, Oliver; Josefsson, Ida; Richter, Robert; Prince, Kevin C; Odelius, Michael; Mucke, Melanie

    2015-10-21

    In this paper, we use a combination of photoelectron spectroscopy, mass spectrometry, and density functional theory calculations to get a detailed understanding of valence single and double ionization and the subsequent dissociation processes. This is exemplified on benchmark systems, trimetallo-dodecacarbonyls M3(CO)12 with M = Ru, Os, where the energy remaining in the molecule after photoionization can be retrieved by measuring the degree of fragmentation of the molecular ion. The intensity of different mass peaks can thus be directly related to ionization cross sections obtained by photoelectron spectroscopy. We find that the M-CO dissociation energy rises as the number of CO ligands decreases due to dissociation. Moreover, ionization of the CO ligands has a higher cross section than that of the metal center for both single and double ionization. After advanced fragmentation, a CO bond can break and the carbon atom remains bonded to the metal core. In addition, we found that the valence ionization cross sections of M3(CO)12 are maximal at about 40 eV photon energy thus showing a more pronounced shape resonance than Ru and Os-complexes with a single metal atom center. Finally, an np → nd giant resonance absorption causes a significant increase of the ionization cross section above 50 eV for Ru3(CO)12. PMID:26493905

  8. 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.

  9. Identification of yrast high-K intrinsic states in {sup 188}Os

    SciTech Connect

    Modamio, V.; Jungclaus, A.; Podolyak, Zs.; Shi, Y.; Xu, F. R.; Algora, A.; Escrig, D.; Fraile, L. M.; Marginean, N.; Martinez, T.; Napoli, D. R.; Schwengner, R.; Ur, C. A.

    2009-02-15

    The high-spin structure of the Z=76 nucleus {sup 188}Os has been studied using the incomplete fusion reaction {sup 7}Li+{sup 186}W. A K{sup {pi}}=10{sup +} band has been established up to spin (24{sup +}) and its crossing with the ground-state band has been studied. In addition, intrinsic high-K states have been identified and on top of two of them, K{sup {pi}}=7{sup -} and K{sup {pi}}=10{sup -}, regular bands have been observed. The K{sup {pi}}=16{sup +} and K{sup {pi}}=18{sup +} states are yrast whereas the K{sup {pi}}=14{sup +} level lies only 33 keV above the yrast line and decays with a low reduced hindrance of f{sub {nu}}<1.3 to the ground-state band ({delta}K=14). The results are discussed by means of a systematic comparison with the even-even neighboring nucleus {sup 186}Os. Configuration-constrained multiquasiparticle potential-energy-surface calculations have been performed to identify the configurations of multiquasiparticle states.

  10. 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.

  11. Infrared evidence of a Slater metal-insulator transition in NaOsO₃.

    PubMed

    Vecchio, I Lo; Perucchi, A; Di Pietro, P; Limaj, O; Schade, U; Sun, Y; Arai, M; Yamaura, K; Lupi, S

    2013-01-01

    The magnetically driven metal-insulator transition (MIT) was predicted by Slater in the fifties. Here a long-range antiferromagnetic (AF) order can open up a gap at the Brillouin electronic band boundary regardless of the Coulomb repulsion magnitude. However, while many low-dimensional organic conductors display evidence for an AF driven MIT, in three-dimensional (3D) systems the Slater MIT still remains elusive. We employ terahertz and infrared spectroscopy to investigate the MIT in the NaOsO₃ 3D antiferromagnet. From the optical conductivity analysis we find evidence for a continuous opening of the energy gap, whose temperature dependence can be well described in terms of a second order phase transition. The comparison between the experimental Drude spectral weight and the one calculated through Local Density Approximation (LDA) shows that electronic correlations play a limited role in the MIT. All the experimental evidence demonstrates that NaOsO₃ is the first known 3D Slater insulator. PMID:24141899

  12. Infrared evidence of a Slater metal-insulator transition in NaOsO3

    PubMed Central

    Vecchio, I. Lo; Perucchi, A.; Di Pietro, P.; Limaj, O.; Schade, U.; Sun, Y.; Arai, M.; Yamaura, K.; Lupi, S.

    2013-01-01

    The magnetically driven metal-insulator transition (MIT) was predicted by Slater in the fifties. Here a long-range antiferromagnetic (AF) order can open up a gap at the Brillouin electronic band boundary regardless of the Coulomb repulsion magnitude. However, while many low-dimensional organic conductors display evidence for an AF driven MIT, in three-dimensional (3D) systems the Slater MIT still remains elusive. We employ terahertz and infrared spectroscopy to investigate the MIT in the NaOsO3 3D antiferromagnet. From the optical conductivity analysis we find evidence for a continuous opening of the energy gap, whose temperature dependence can be well described in terms of a second order phase transition. The comparison between the experimental Drude spectral weight and the one calculated through Local Density Approximation (LDA) shows that electronic correlations play a limited role in the MIT. All the experimental evidence demonstrates that NaOsO3 is the first known 3D Slater insulator. PMID:24141899

  13. σ-Aromaticity in polyhydride complexes of Ru, Ir, Os, and Pt.

    PubMed

    Jimenez-Izal, Elisa; Alexandrova, Anastassia N

    2016-04-28

    Transition-metal hydrides represent a unique class of compounds, which are essential for catalysis, organic synthesis, and hydrogen storage. In this work we study IrH5(PPh3)2, (RuH5(P(i)Pr3)2)(-), (OsH5(P(i)Pr3)2)(-), and OsH4(PPhMe2)3 polyhydride complexes, inspired by the recent discovery of the σ-aromatic PtZnH5(-) cluster anion. The distinctive feature of these molecules is that, like in the PtZnH5(-) cluster, the metal is five-fold coordinated in-plane, and holds additional ligands at the axial positions. This work shows that the unusual coordination in these compounds indeed can be explained by σ-aromaticity in the pentagonal arrangement, stabilized by the atomic orbitals on the metal. Based on this newly elucidated bonding principle, we additionally propose a new family of polyhydrides that display a uniquely high coordination. We also report the first indications of how aromaticity may impact the reactivity of these molecules. PMID:26414992

  14. Ionization and photofragmentation of Ru3(CO)12 and Os3(CO)12

    NASA Astrophysics Data System (ADS)

    Schalk, Oliver; Josefsson, Ida; Richter, Robert; Prince, Kevin C.; Odelius, Michael; Mucke, Melanie

    2015-10-01

    In this paper, we use a combination of photoelectron spectroscopy, mass spectrometry, and density functional theory calculations to get a detailed understanding of valence single and double ionization and the subsequent dissociation processes. This is exemplified on benchmark systems, trimetallo-dodecacarbonyls M3(CO)12 with M = Ru, Os, where the energy remaining in the molecule after photoionization can be retrieved by measuring the degree of fragmentation of the molecular ion. The intensity of different mass peaks can thus be directly related to ionization cross sections obtained by photoelectron spectroscopy. We find that the M—CO dissociation energy rises as the number of CO ligands decreases due to dissociation. Moreover, ionization of the CO ligands has a higher cross section than that of the metal center for both single and double ionization. After advanced fragmentation, a CO bond can break and the carbon atom remains bonded to the metal core. In addition, we found that the valence ionization cross sections of M3(CO)12 are maximal at about 40 eV photon energy thus showing a more pronounced shape resonance than Ru and Os-complexes with a single metal atom center. Finally, an np → nd giant resonance absorption causes a significant increase of the ionization cross section above 50 eV for Ru3(CO)12.

  15. Hepatic FoxOs Regulate Lipid Metabolism via Modulation of Expression of the Nicotinamide Phosphoribosyltransferase Gene*

    PubMed Central

    Tao, Rongya; Wei, Dan; Gao, Hanlin; Liu, Yunlong; DePinho, Ronald A.; Dong, X. Charlie

    2011-01-01

    FoxO transcription factors have been implicated in lipid metabolism; however, the underlying mechanisms are not well understood. Here, in an effort to elucidate such mechanisms, we examined the phenotypic consequences of liver-specific deletion of three members of the FoxO family: FoxO1, FoxO3, and FoxO4. These liver-specific triply null mice, designated LTKO, exhibited elevated triglycerides in the liver on regular chow diet. More remarkably, LTKO mice developed severe hepatic steatosis following placement on a high fat diet. Further analyses revealed that hepatic NAD+ levels and Sirt1 activity were decreased in the liver of the LTKO mice relative to controls. At the mechanistic level, expression profile analyses showed that LTKO livers had significantly down-regulated expression of the nicotinamide phosphoribosyltransferase (Nampt) gene encoding the rate-limiting enzyme in the salvage pathway of NAD+ biosynthesis. Luciferase reporter assays and chromatin immunoprecipitation analyses demonstrated that Nampt is a transcriptional target gene of FoxOs. Significantly, overexpression of Nampt gene reduced, whereas knockdown increased, hepatic triglyceride levels in vitro and in vivo. Thus, FoxOs control the Nampt gene expression and the NAD+ signaling in the regulation of hepatic triglyceride homeostasis. PMID:21388966

  16. Compressibility of Ru and Os in Comparison with Hcp ɛ -Fe; the lowest measured compressibility

    NASA Astrophysics Data System (ADS)

    Cynn, H.; Yoo, C.; Iota, V.; Baer, B.

    2001-12-01

    The hardness of a material is strongly correlated with its bulk modulus; thus, the search for superhard materials often becomes the search for very low compressibilities. Diamond is the hardest known material and has the highest known bulk modulus, B0 = 443 GPa (or the lowest compressibility, β = 0.226 Mbar-1). In this paper, we present surprising experimental findings that metallic elements like Os, Ir, and Ru are also good candidates for superhard materials based on their measured low compressibilities. We also present the pressure volume relationships of Ru, Os, and Ir to 70 GPa, in comparison with those of ɛ -Fe, W and C. The results are in a systematic agreement with the change of the bulk moduli and also with the first-principles electronic structure calculations. However, the c/a ratios of the 4,5d-transition metals show a slightly different trend from that of 3d ɛ -Fe at high pressures. Because of the similarity in electronic structure of these metals and Fe, the major constituent of the Earth's core, the EOS's and crystal structural parameters of the Group VIIIA transition metals reported in this paper are central to understanding the Earth's core mineral physics. This work was performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

  17. Spectroscopic calculations of the low-lying structure in exotic Os and W isotopes

    SciTech Connect

    Nomura, K.; Otsuka, T.; Rodriguez-Guzman, R.; Sarriguren, P.; Robledo, L. M.; Regan, P. H.; Stevenson, P. D.; Podolyak, Zs.

    2011-05-15

    Structural evolution in neutron-rich Os and W isotopes is investigated in terms of the interacting boson model (IBM) Hamiltonian determined by (constrained) Hartree-Fock-Bogoliubov calculations with the Gogny-D1S energy density functional (EDF). The interaction strengths of the IBM Hamiltonian are produced by mapping the potential energy surface (PES) of the Gogny-EDF with quadrupole degrees of freedom onto the corresponding PES of the IBM system. We examine the prolate-to-oblate shape/phase transition which is predicted to take place in this region as a function of neutron number N within the considered Os and W isotopic chains. The onset of this transition is found to be more rapid compared to the neighboring Pt isotopes. The calculations also allow the prediction of spectroscopic variables (excited state energies and reduced transition probabilities) which are presented for the neutron-rich {sup 192,194,196}W nuclei, for which there is only very limited experimental data available to date.

  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. 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. PMID:26879413

  20. 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

  1. Tissue-specific expression, developmentally and spatially regulated alternative splicing, and protein subcellular localization of OsLpa1 in rice*

    PubMed Central

    Lu, Hai-ping; Pang, Wei-qin; Li, Wen-xu; Tan, Yuan-yuan; Wang, Qing; Zhao, Hai-jun; Shu, Qing-yao

    2016-01-01

    The OsLpa1 gene (LOC_Os02g57400) was identified to be involved in phytic acid (PA) metabolism because its knockout and missense mutants reduce PA content in rice grain. However, little is known about the molecular characteristics of OsLpa1 in rice and of its homologues in other plants. In the present study, the spatial pattern of OsLpa1 expression was revealed using OsLpa1 promoter::GUS transgenic plants (GUS: β-glucuronidase); GUS histochemical assay showed that OsLpa1 was strongly expressed in stem, leaf, and root tissues, but in floral organ it is expressed mainly and strongly in filaments. In seeds, GUS staining was concentrated in the aleurone layers; a few blue spots were observed in the outer layers of embryo, but no staining was observed in the endosperm. Three OsLpa1 transcripts (OsLpa1.1, OsLpa1.2, OsLpa1.3) are produced due to alternative splicing; quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis revealed that the abundance of OsLpa1.3 was negligible compared with OsLpa1.1 and OsLpa1.2 in all tissues. OsLpa1.2 is predominant in germinating seeds (about 5 times that of OsLpa1.1), but its abundance decreases quickly with the development of seedlings and plants, whereas the abundance of OsLpa1.1 rises and falls, reaching its highest level in 45-d-old plants, with abundance greater than that of OsLpa1.2 in both leaves and roots. In seeds, the abundance of OsLpa1 continuously increases with seed growth, being 27.5 and 15 times greater in 28-DAF (day after flowering) seeds than in 7-DAF seeds for OsLpa1.1 and OsLpa1.2, respectively. Transient expression of chimeric genes with green fluorescence protein (GFP) in rice protoplasts demonstrated that all proteins encoded by the three OsLpa1 transcripts are localized to the chloroplast. PMID:26834011

  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. The OsCYP19-4 Gene Is Expressed as Multiple Alternatively Spliced Transcripts Encoding Isoforms with Distinct Cellular Localizations and PPIase Activities under Cold Stress

    PubMed Central

    Lee, Areum; Lee, Sang Sook; Jung, Won Yong; Park, Hyun Ji; Lim, Bo Ra; Kim, Hyun-Soon; Ahn, Jun Cheul; Cho, Hye Sun

    2016-01-01

    Alternative splicing (AS) is an important molecular mechanism by which single genes can generate multiple mRNA isoforms. We reported previously that, in Oryza sativa, the cyclophilin 19-4 (OsCYP19-4.1) transcript was significantly upregulated in response to cold stress, and that transgenic plants were cold tolerant. Here we show that, under cold stress, OsCYP19-4 produces eight transcript variants by intron retention and exon skipping, resulting in production of four distinct protein isoforms. The OsCYP19-4 AS isoforms exhibited different cellular localizations in the epidermal cells: in contrast to OsCYP19-4.1, the OsCYP19-4.2 and OsCYP19-4.3 proteins were primarily targeted to guard and subsidiary cells, whereas OsCYP19-4.5, which consists largely of an endoplasmic reticulum (ER) targeting signal, was co-localized with the RFP-BiP marker in the ER. In OsCYP19-4.2, the key residues of the PPIase domain are altered; consistent with this, recombinant OsCYP19-4.2 had significantly lower PPIase activity than OsCYP19-4.1 in vitro. Specific protein-protein interactions between OsCYP19-4.2/3 and AtRCN1 were verified in yeast two-hybrid (Y2H) and bimolecular fluoresence complementation (BiFC assays), although the OsCYP19-4 isoforms could not bind each other. Based on these results, we propose that two OsCYP19-4 AS isoforms, OsCYP19-4.2 and OsCYP19-4.3, play roles linking auxin transport and cold stress via interactions with RCN1. PMID:27447607

  4. The OsCYP19-4 Gene Is Expressed as Multiple Alternatively Spliced Transcripts Encoding Isoforms with Distinct Cellular Localizations and PPIase Activities under Cold Stress.

    PubMed

    Lee, Areum; Lee, Sang Sook; Jung, Won Yong; Park, Hyun Ji; Lim, Bo Ra; Kim, Hyun-Soon; Ahn, Jun Cheul; Cho, Hye Sun

    2016-01-01

    Alternative splicing (AS) is an important molecular mechanism by which single genes can generate multiple mRNA isoforms. We reported previously that, in Oryza sativa, the cyclophilin 19-4 (OsCYP19-4.1) transcript was significantly upregulated in response to cold stress, and that transgenic plants were cold tolerant. Here we show that, under cold stress, OsCYP19-4 produces eight transcript variants by intron retention and exon skipping, resulting in production of four distinct protein isoforms. The OsCYP19-4 AS isoforms exhibited different cellular localizations in the epidermal cells: in contrast to OsCYP19-4.1, the OsCYP19-4.2 and OsCYP19-4.3 proteins were primarily targeted to guard and subsidiary cells, whereas OsCYP19-4.5, which consists largely of an endoplasmic reticulum (ER) targeting signal, was co-localized with the RFP-BiP marker in the ER. In OsCYP19-4.2, the key residues of the PPIase domain are altered; consistent with this, recombinant OsCYP19-4.2 had significantly lower PPIase activity than OsCYP19-4.1 in vitro. Specific protein-protein interactions between OsCYP19-4.2/3 and AtRCN1 were verified in yeast two-hybrid (Y2H) and bimolecular fluoresence complementation (BiFC assays), although the OsCYP19-4 isoforms could not bind each other. Based on these results, we propose that two OsCYP19-4 AS isoforms, OsCYP19-4.2 and OsCYP19-4.3, play roles linking auxin transport and cold stress via interactions with RCN1. PMID:27447607

  5. Deregulation of the OsmiR160 Target Gene OsARF18 Causes Growth and Developmental Defects with an Alteration of Auxin Signaling in Rice.

    PubMed

    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

  6. 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

  7. Pincharse sin infectarse: estrategias para prevenir la infección por el VIH y el VHC entre usuarios de drogas inyectables

    PubMed Central

    MATEU-GELABERT, P.; FRIEDMAN, S.; SANDOVAL, M.

    2011-01-01

    infectarse por el VIH (sólo un doble negativo tuvo un amplio conocimiento sobre la hepatitis C). Estas intencionalidades no son mutuamente excluyentes. La presencia de varias refuerza la puesta en práctica a diario de comportamientos que pueden ayudar al que se inyecta a mantenerse libre de infecciones durante años. Algunas prácticas que hemos identificado se implementan en grupo y se comunican de UDI a UDI, de esta manera se extienden entre algunas redes sociales de UDI. Conclusiones Los UDI que permanecen sin infectarse planean e implementan estrategias de prevención en circunstancias donde otros UDI aplican prácticas de riesgo. El mantenimiento de la no infección no es, por lo tanto, un resultado del azar, sino más bien el resultado del esfuerzo (agencia) de los UDI. Investigar y extender estas estrategias y tácticas a través de programas de prevención podría contribuir a la prevención del VIH y el VHC. PMID:21915175

  8. Ancient mantle trapped in the Mariana arc-basin system: Insights from the platinum group elements and Os isotopes

    NASA Astrophysics Data System (ADS)

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

    2006-12-01

    Serpentinized harzburgites recently drilled during ODP Leg 195 at South Chamorro Seamount in the Mariana forearc region have been studied for their platinum group element (PGE) concentrations and Os isotopic compositions. The samples allow a look at the slab fluid-modified subarc mantle immediately overlaying the actively subducting Pacific slab at depths of ~ 30 km. The average PGE (Os 2.3 ppb, Ir 1.5 ppb, Ru 5.4 ppb, Pd 1.6 ppb and Pt 16.3 ppb) and Re (60 ppt) abundances are comparable to those measured in other subarc mantle xenolith suites. The PGE and Re abundances are depleted up to 3 orders of magnitude relative to chondrites, with relative order of depletions Ru > Os > Ir> Pt> Re> Pd. The variable Pd contents (0.01-4.5 ppb) and the low Pd/Os (<2) in the Mariana forearc samples differ significantly from that of altered oceanic crust (Pd/Os~ 22), suggesting Os remained relatively unchanged during low temperature subduction-fluid additions. Serpentinitization of the harzburgites occurred in equilibrium with fluids that were both reducing and highly alkaline. Os in its original phases may be stabilized in such an environment, therefore can preserve evidence for ancient melting despite later slab interactions. Finally, the high Pt/Pd (ave. ~ 25) and low Re contents (ave.~ 60 ppt) in the Leg 195 forearc samples are complementary to those measured in boninites from the Izu-Bonin-Mariana arc-basin system, showing a genetic relationship. Our samples reveal an average 187Os/188Os of 0.123 [range = 0.119- 0.127], making them similar to abyssal peridotites from elsewhere. Radiogenic 187Os/188Os ratios would have been imparted to the serpentinites by slab fluids, so the subchondritic Os isotopic compositions implies that peridotite-slab fluid interactions did not alter the Os isotope systematics of the mantle protoliths. Low alumina abundances (<1 %) and trace element signatures (low HFSE; REE with U-shaped chondrite-normalized patterns and 2-3 times lower than

  9. 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

  10. 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