Search results for "yellow"

Mitochondrial Dna Variation in Rhopalosiphum padi (Homoptera: Aphididae) Populations from four Spanish Localities

1992

In total, 35 clones of the bird cherry-oat aphid, Rhopalosiphum padi (L.) established from samples collected in four distant localities of Spain during fall 1989 and spring 1990 were examined for mitochondrial DNA variation using 20 restriction endonucleases. Individual parthenogenetic adults were used to establish clonal lines on wheat (‘Talento’) seedlings. Restriction site polymorphism was detected only with endonuclease Rsa I, but no statistical treatment of data could be done until more polymorphic endonucleases are found. Length variation of the mitochondrial DNA molecule, however, was extensive among R. padi clones. Distribution among populations of this size polymorphism was used to…

Invasion biology and host specificity of the grapevine yellows disease vector Hyalesthes obsoletus in Europe

2008

Within the past 10 years, the yellows disease ‘bois noir’ (BN) has become one of the commercially most important diseases of grapevine [ Vitis vinifera L. (Vitaceae)] in Europe. Infection pressure is caused by phytoplasmas of the stolbur 16SrXII-A group that are transmitted by a planthopper vector, Hyalesthes obsoletus Signoret (Homoptera: Auchenorrhyncha). Infestation happens as an accidental side-effect of the feeding behaviour of the vector, as vector and pathogen proliferation is dependent on other plants. In Germany, the increase of BN is correlated with the use of a new host plant by the vector, increase in abundance of the vector on the new host plant, and dissemination of host plant…

Dendritic pattern development of the honeybee antennal lobe neurons: a laser scanning confocal microscopic study

1999

The processing of odorant signals is performed, in the olfactory bulb of vertebrates or in the antennal lobe of insects, by different types of neurons which display specific morphological and functional features. The present work characterizes the morphogenesis of the main neuronal types which participate in olfactory discrimination in the adult honeybee (Apis mellifera). Neurons were stained intracellularly with Lucifer yellow at different stages of pupal development and in the adult, and imaged by laser scanning confocal microscopy. Attending to branching patterns, all pupal neurons could be attributed to morphological types previously established in the adult. Given the functional import…

Hepatitis Due to Non-A-E Viruses

2011

VLTI/AMBER spectro-interferometry of the late-type supergiants V766 Cen (=HR 5171 A), σ Oph, BM Sco, and HD 206859

2017

Aims. We add four warmer late-type supergiants to our previous spectro-interferometric studies of red giants and supergiants. Methods. We measure the near-continuum angular diameter, derive fundamental parameters, discuss the evolutionary stage, and study extended atmospheric atomic and molecular layers. Results. V766 Cen (=HR 5171 A) is found to be a high-luminosity (log L/L = 5.8 ± 0.4) source of effective temperature 4290 ± 760 K and radius 1490 ± 540 R, located in the Hertzsprung-Russell (HR) diagram close to both the Hayashi limit and Eddington limit; this source is consistent with a 40 M evolutionary track without rotation and current mass 27-36 M. V766 Cen exhibits Na i in emission a…

Portable Spectroscopic Techniques for the Non-invasive Identification of two historical yellow pigments: Applications and Practical Challenges

2022

Abstract Decades of technological advances in instrumental analysis have transformed many techniques from laboratory in portable analytical tools with increasing their applicability in situ to the study of cultural heritage. It is known that the painting realisation varies from artist to artist, and the identification of the pigments provides a decisive contribution to trace their authenticity and to support an appropriate restoration work. However, in some cases, due to the complexity of painting composition, it is difficult to distinguish between pigments having a similar chemical composition and colour. Here, a systematic study through combined use of portable non-invasive spectroscopic …

“Curious Victories”: The Famous Murder Case of Maria Barbella and Italian-American Women in the Press Between the 1890s and 1910s

2019

Immigrant women during the period of mass migration received little public attention. However, when some of them became protagonists in sensational murder cases, they burst into the public sphere. Analyzing the representation of Maria Barbella's trial in the mainstream, yellow and the Italian-American press shows how some of these invisible women were able to assert themselves in the public sphere and achieve a degree of agency despite their tragic circumstances. These women, represented as degenerate and genetically inferior in the early coverage of their cases and trials, were, over time, essentially rehabilitated in the press as “proper” American subjects as a result of the convergence o…

Infection of Bois-Noir tuf-type-I stolbur phytoplasma inHyalesthes obsoletus(Hemiptera: Cixiidae) larvae and influence on larval size

2009

Recent dramatic spread of the grapevine yellows disease Bois Noir (BN) in Germany is above all explained by highly increased abundances of the vector Hyalesthes obsoletus (Hemiptera: Cixiidae) associated to the plant Urtica dioica, the reservoir of the BN pathogen stolbur tuf-type-I. The vector acquires BN-phytoplasma as larvae whilst feeding on the roots of infected U. dioica. To understand the dynamics of the Urticacycle, we tested at what instar larvae become infected and whether infection affects larvae size (i.e. growth) at two sites in the Mosel Valley, Germany. Larvae were tested from infected plants and collected at instar-stages 3, 4 and 5. Larvae at stage 3 were already infected b…

Yellow (577 nm) micropulse laser versus half-dose verteporfin photodynamic therapy in eyes with chronic central serous chorioretinopathy: results of …

2018

PurposeTo compare the functional and anatomical outcomes of eyes with chronic central serous chorioretinopathy treated with yellow micropulse (MP) laser versus half-dose verteporfin photodynamic therapy (PDT).MethodsThis is a multicentre, retrospective comparative study of 92 eyes treated with yellow MP laser (duty cycle of 5%, zero spacing between spots, spot size varied from 100 to 200 µm, power varied from 320 to 660 mW, and the pulse burst duration was 200 ms) and 67 eyes treated with PDT (half-dose verteporfin (3 mg/m2) infused over 10 min), followed by laser activation for 83 s. Spot sizes varied from 400 to 2000 µm.ResultsIn the MP group, at 12 months of follow-up, the mean best corr…

Formation of two-dimensional crystals of icosahedral RNA viruses.

2007

International audience; The formation of 2D arrays of three small icosahedral RNA viruses with known 3D structures (tomato bushy stunt virus, turnip yellow mosaic virus and bromegrass mosaic virus) has been investigated to determine the role of each component of a negative staining solution containing ammonium molybdate and polyethylene glycol. Virion association was monitored by dynamic light scattering (DLS) and virus array formation was visualised by conventional transmission electron microscopy and cryo-electron microscopy after negative staining. The structural properties of viral arrays prepared in vitro were compared to those of microcrystals found in the leaves of infected plants. A…