Volumetric microvascular imaging of human retina using optical coherence tomography with a novel motion contrast technique

Phase variance-based motion contrast imaging is demonstrated using a spectral domain optical coherence tomography system for the in vivo human retina. This contrast technique spatially identifies locations of motion within the retina primarily associated with vasculature. Histogram-based noise analysis of the motion contrast images was used to reduce the motion noise created by transverse eye motion. En face summation images created from the 3D motion contrast data are presented with segmentation of selected retinal layers to provide non-invasive vascular visualization comparable to currently used invasive angiographic imaging. This motion contrast technique has demonstrated the ability to visualize resolution-limited vasculature independent of vessel orientation and flow velocity

Spectral radiometry and tropospheric aerosols: Report of panel

The term aerosols, as used here, refers to the haze, smoke, and dust that appear in the troposphere. The term does not refer to the hydrometeors in cumulus and stratus clouds but does include the sulfuric acid-water droplets which are assumed to predominate in the stratospheric aerosol layer. The aerosol properties that were measured from satellites and those which can be made in the near term (up to 1992) will be reviewed. The capabilities that will exist in the years 1992 to 2000, with implementation of EOS, are then discussed. Finally, a few words will be said concerning the potential for aerosol measurements for the decade after 2000

Algorithm for Atmospheric Corrections of Aircraft and Satellite Imagery

A simple and fast atmospheric correction algorithm is described which is used to correct radiances of scattered sunlight measured by aircraft and/or satellite above a uniform surface. The atmospheric effect, the basic equations, a description of the computational procedure, and a sensitivity study are discussed. The program is designed to take the measured radiances, view and illumination directions, and the aerosol and gaseous absorption optical thickness to compute the radiance just above the surface, the irradiance on the surface, and surface reflectance. Alternatively, the program will compute the upward radiance at a specific altitude for a given surface reflectance, view and illumination directions, and aerosol and gaseous absorption optical thickness. The algorithm can be applied for any view and illumination directions and any wavelength in the range 0.48 micron to 2.2 micron. The relation between the measured radiance and surface reflectance, which is expressed as a function of atmospheric properties and measurement geometry, is computed using a radiative transfer routine. The results of the computations are presented in a table which forms the basis of the correction algorithm. The algorithm can be used for atmospheric corrections in the presence of a rural aerosol. The sensitivity of the derived surface reflectance to uncertainties in the model and input data is discussed

Selective Tooth Clipping in the Management of Low-Birth-Weight Piglets

A study was designed to test the potential benefits of selective tooth clipping (the practice of leaving the eye teeth intact in the smallest piglets of a litter to make them more competitive) under commercial conditions. A total of 346 litters were assigned to either the control treatment where all piglets had their teeth clipped, or the experimental treatment where one or more piglets of low birth weight had their teeth left intact. Piglets were weighed within 24 h of birth and at 7, 21 and 56 d. In litters of 12-14 animals, but not in smaller litters, the lower-birth-weight piglets had lower mortality in experimental than in control litters (32.0 vs. 39.8%), whereas higher-birth-weight piglets showed a trend in the opposite direction, with 14.4% mortality in experimental vs. 13.2% in control litters (P = 0.05. The weight gain of lower-birth-weight piglets was greater (166 vs. 143 g d‒1) in experimental than in control litters of 9-11 piglets, but the heavier piglets competing against the small litter-mates with intact teeth had lower weight gains than the controls (177 vs. 187 g d‒1) (P \u3c 0.02). Within-litter variance of 21-d weights was about 15% smaller (P \u3c 0.005) in experimental than in control litters. Thus, selective tooth-clipping does not improve overall growth and survival, but it contributes to more uniform weaning weights and may help the most vulnerable piglets to remain alive until fostering or other intervention can be accomplished

Creation of orbital angular momentum states with chiral polaritonic lenses

Controlled transfer of orbital angular momentum to exciton-polariton Bose-Einstein condensate spontaneously created under incoherent, off-resonant excitation conditions is a long-standing challenge in the field of microcavity polaritonics. We demonstrate, experimentally and theoretically, a simple and efficient approach to generation of nontrivial orbital angular momentum states by using optically-induced potentials -- chiral polaritonic lenses.Comment: 5 pages, 5 figure

Light drinking in pregnancy and mid-childhood mental health and learning outcomes

OBJECTIVE: To investigate whether light drinking in pregnancy is associated with adverse child mental health and academic outcomes. DESIGN: Using data from the prospective, population-based Avon Longitudinal Study of Parents and Children (ALSPAC), we investigated the associations between light drinking in pregnancy (<1 glass per week in the first trimester) and child mental health (using both parent and teacher rated Strengths and Difficulties Questionnaires (SDQs)) and academic outcomes based on Key Stage 2 examination results at age 11 years. PARTICIPANTS: 11-year-old children from ALSPAC with parent (n=6587) and teacher (n=6393) completed SDQs and data from Key Stage 2 examination results (n=10 558). RESULTS: 39% of women had consumed <1 glass per week and 16% ≥1 glass per week of alcohol during the first trimester (45% abstaining). After adjustment, relative to abstainers, there was no effect of light drinking on teacher-rated SDQ scores or examination results. In girls, although there was a suggestion of worse outcomes (adjusted regression coefficient=0.38; 95% CI 0.01 to 0.74) on the parent-rated total SDQ score in those exposed to light drinking compared to abstainers, no dose-response relationship was evident. CONCLUSIONS: Although the pattern of findings involving parent ratings for girls exposed to light drinking is consistent with earlier findings from this cohort, the overall lack of any adverse effects of light drinking is similar to findings from other recent cohort studies. Light drinking in pregnancy does not appear to be associated with clinically important adverse effects for mental health and academic outcomes at the age of 11 years

“The waste that lies before me”: The Public and the Private Worlds of Robert Baldwin

Les auteurs nous proposent ici de jeter un nouveau regard sur le personnage de Robert Baldwin, l'un des grands promoteurs de l'instauration du principe de la responsabilité ministérielle au pays. L'image que l'on a connue de lui jusqu'à présent en est surtout une d'un politicien intègre, d'un gentilhomme accompli, d'un homme public d'une grande réserve qui donnait même souvent l'impression d'être un peu terne, voire sans grande passion.Or, l'étude de nouvelles sources le concernant nous le révèle plutôt comme ayant été un personnage tourmenté, inquiet et d'une grande sensibilité. Il conçut d'ailleurs très tôt une immense passion pour une jeune cousine qu'il épousa, en 1827, à l'âge de 23 ans. Les années qu'il vécut avec cette femme dont il était profondément épris - et qui, semble-t-il, le lui rendait bien - furent sans doute les seules années heureuses de sa vie. Ils eurent ensemble quatre enfants mais elle se releva difficilement de sa dernière grossesse dont elle avait été délivrée par césarienne et mourut, en 1836, après seulement neuf années de mariage.En dépit du chagrin et de la douleur qu'il en ressentit, Baldwin ne quitta pas la vie publique mais il vécut le reste de sa vie en se remémorant les années passées avec elle et en érigeant sa peine en une espèce de culte centré sur la célébration de leur amour. Gestes, objets et événements lui rappelaient les diverses étapes de leur vie commune et il poussa la dévotion jusqu'à prescrire par testament qu'on lui fasse, après sa mort, la même incision que sa femme avait dû subir lors de la naissance de leur dernier enfant. Sa mélancolie s'accentua d'ailleurs avec les années. Déjà, en 1850, il était réduit à l'incapacité pendant plusieurs mois et il mourut quelques années plus tard, au cours des derniers mois de 1858

Quantitative mapping of intracardiac blood flow in embryonic zebrafish

Using real-time in vivo imaging and digital particle image velocimetry (DPIV) we quantitatively described the intracardiac flow environment of early zebrafish (Danio rerio) embryos. Gross cardiac dynamics were defined for two embryonic stages: 4.5 days post fertilization (dpf) and 37 hours post fertilization (hpf) using high-speed transmitted light microscopy with valve dynamics visualized through high-speed laser-scanning microscopy on transgenic embryos expressing GFP