Angular leaf spot

Angular leaf spot, caused by the fungus Isariopsis griseola in tropical and subtropical regions, can cause losses up to 50 percent. The pathogen infects the leaves by entering through the stomata or can be transmitted by the seed. Disease control can be carried out by cultural practices, use of disease-free seeds, planting in well-drained soils, the removal of infected harvest debris, and the utilization of chemical products and resistant var. Color illustrations are given of the symptoms and damage caused by the disease. (CIAT)La mancha foliar angular, causada por el hongo Isariopsis griseola en las regiones tropicales y subtropicales, puede ocasionar perdidas de hasta 50 por ciento. El patogeno infecta las hojas penetrando a traves de los estomas o puede transmitirse por la semilla. El control de la enfermedad se puede realizar mediante practicas culturales, utilizacion de semillas libres del patogeno, siembra en suelos bien drenados y eliminacion de residuos de cosecha infectados, y utilizacion de productos quimicos y de var. resistentes. Se dan ilustraciones a color de los sintomas y el dano causado por la enfermedad. (RA

Las especies silvestres en el mejoramiento varietal del arroz

Wild species in varietal improvement of rice In 1994 the CIAT Rice Project launched a pre-breeding program that crossed the species Oryza rufipogon, O. barthii, and O. glaberrima (O. latifolia was recently introduced) with commercial irrigated and upland rice varieties, using a backcrossing scheme that incorporates genes of interest of wild species into cultivated rice. The results emphasize the importance of wild species in improving rice cultivars using both conventional methods and marker-assisted selection. The degree of polymorphism found in crosses of wild species with O. sativa was much higher (90%) than that found in crosses of indica x japonica cultivars (46%). In conclusion, the use of new exotic germplasm in rice improvement can have a substantial impact on rice productivity, its resistance to several biotic and abiotic stresses, and its nutritional and agroindustrial quality. National rice programs of Latin America can access the genetic variability thus generated in the CIAT-ION nurseries. Programs in Bolivia, Panama, and Nicaragua, for example, identified several lines derived from crosses between O. sativa x O. glaberrima and between O. sativa x O. rufipogon that show good yield potential, tolerance to major pests and diseases, good-quality grain, and good adaptability. Some of these lines were launched as commercial varieties in 2009 and 2010.En 1994, el Proyecto de Arroz del CIAT inició un programa de pre-mejoramiento en el que se tomaron las especies Oryza rufipogon, O. barthii y O. glaberrima (recientemente se introdujo O. latifolia) para cruzarlas con variedades comerciales de arroz de riego y de secano, mediante un esquema de retrocruzamientos que incorpora genes de interés de las especies silvestres en el arroz cultivado. Los resultados subrayan la importancia de las especies silvestres en el mejoramiento de los cultivares de arroz, tanto por el método convencional como mediante la selección asistida por marcadores. El grado de polimorfismo encontrado en los cruces de especies silvestres con O. sativa fue mucho mayor (90%) que el encontrado en los cruces de cultivares índica x cultivares japónica (46%). En conclusión, el uso del nuevo germoplasma exótico en el mejoramiento del arroz puede tener un impacto sustancial en la productividad del arroz, en su resistencia a varias limitantes bióticas y abióticas, y en su calidad nutricional y agroindustrial. La variabilidad genética así generada está a disposición de los programas nacionales de arroz de América Latina en los viveros CIAT-ION. Los programas de Bolivia, Panamá y Nicaragua, por ejemplo, identificaron algunas líneas derivadas de cruces entre O. sativa x O. glaberrima y entre O. sativa x O. rufipogon, con buen potencial de rendimiento, tolerancia a las principales plagas y enfermedades, producción de grano de buena calidad y buena capacidad de adaptación. Algunas de estas líneas fueron liberadas como variedades comerciales en 2009 y 2010

Determining science teachers’ ideas about the science process skills: a case study

AbstractThe aim of this study is to investigate science teachers’ ideas about the science process skills (SPS) using qualitative analysis. This study was carried out at the first term of 2008- 2009 academic year. A case study research methodology was used. The sample of this study consisted of 10 science teachers (ST), who has been working at Giresun center elementary schools in Turkey. A semi-structured interview procedure was used to collect data. The collected data were analyzed with Nvivo 8 program. The results indicate that the majority of sample have not had widespread theoretical knowledge on SPS

Identification of new sources of resistance to RHBV- rice hoja blanca virus

With the aim to find new sources of resistance to rice hoja blanca (white leaf) disease, transmitted by the insect Tagosodes orizicolus, 660 genotypes were evaluated under greenhouse and field conditions. Seven resistant genotypes were identified, and genomic studies were performed to demonstrate that the resistance in these sources is genetically different from that of Fedearroz 2000, which is currently the variety with the most resistance to hoja blanca. These new resistance sources constitute a resource that can be used to sustainably extend hoja blanca disease management throughout all of the rice-growing regions of tropical America. This is the first report of hoja blanca resistance in indica rice and different from that of Fedearroz 2000.Con el objetivo de encontrar nuevas fuentes de resistencia a la enfermedad de la hoja blanca del arroz, transmitida por el insecto Tagosodes orizicolus, se evaluaron 660 genotipos en condiciones de invernadero y campo. Se identificaron siete genotipos con resistencia a la enfermedad y se realizaron estudios del genoma para evidenciar que eran genéticamente diferentes a Fedearroz 2000, la variedad de mejor comportamiento ante el virus, en el momento. Estas nuevas fuentes de resistencia constituyen un recurso que puede utilizarse para extender un manejo sostenible de la enfermedad, en todas las regiones productoras de arroz en América tropical. Este es el primer reporte de fuentes de resistencia, tipo indica, diferentes a Fedearroz 2000

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

Impact of safety-related dose reductions or discontinuations on sustained virologic response in HCV-infected patients: Results from the GUARD-C Cohort

BACKGROUND: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. METHODS: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0-9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively. RESULTS: SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced 651 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with 651 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not 655. CONCLUSIONS: In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V