Woofer-tweeter adaptive optics scanning laser ophthalmoscopic imaging based on Lagrange-multiplier damped least-squares algorithm

We implemented a Lagrange-multiplier (LM)-based damped least-squares (DLS) control algorithm in a woofer-tweeter dual deformable-mirror (DM) adaptive optics scanning laser ophthalmoscope (AOSLO). The algorithm uses data from a single Shack-Hartmann wavefront sensor to simultaneously correct large-amplitude low-order aberrations by a woofer DM and small-amplitude higher-order aberrations by a tweeter DM. We measured the in vivo performance of high resolution retinal imaging with the dual DM AOSLO. We compared the simultaneous LM-based DLS dual DM controller with both single DM controller, and a successive dual DM controller. We evaluated performance using both wavefront (RMS) and image quality metrics including brightness and power spectrum. The simultaneous LM-based dual DM AO can consistently provide near diffraction-limited in vivo routine imaging of human retina

No disk needed around HD 199143 B

We present new, high angular resolution images of HD 199143 in the Capricornus association, obtained with the adaptive optics system ADONIS+SHARPII at the ESO 3.6m Telescope of La Silla Observatory. HD 199143 and its neighbour star HD 358623 (separation 5'away) have previously been imaged with adaptive optics. For each star, a companion has been detected in the J and K bands at respective separations of 1.1'' and 2.2'' (Jayawardhana & Brandeker 2001). Our new photometry of HD 199143 B suggests that it is a M2 star and that the presence of circumstellar dust proposed by Van den Ancker et al. (2000) is no longer necessary. We show that the 12 microns flux detected by IRAS previously interpreted as an IR excess, can be explained by the presence of the late-type companion.Comment: 5 pages, 4 figure

The Biology of Canadian Weeds. [#]. Daphne laureola L.

Daphne (Daphne laureola L.) is a perennial evergreen shrub native to Eurasia and Northern Africa. Introduced to North America as an ornamental shrub, the plant has readily absconded gardens and can now be found throughout suitable habitats on both the east and west coasts of the continent. In Canada, daphne has naturalized in southwestern British Columbia including Vancouver, southern Vancouver Island, and the Gulf Islands. Daphne is of particular concern to the endangered Garry oak (Quercus garryana Douglas) because it invades shady woodland areas, forming dense mono-specific stands that can suppress and inhibit native vegetation. The berries and all other parts of the daphne plant contain a mixture of toxic chemicals that can be fatal to humans or animals if ingested. Removal teams suggest using gloves for elimination and handling of daphne because of its corrosive sap and oil. Widespread planting combined with a lack of public knowledge regarding the speciesâ invasiveness has created great concern over its potential to spread. Various methods of control (chemical, manual, and biological) have been developed. The most commonly applied approach in Canada is manual control, but care must be taken to avoid contact with skin and follow-up monitoring and control is advised. A promising biocontrol agent is the fungus Phomopsis sp. Nov., which has been observed to cause high levels of mortality in D. laureola under both laboratory and field conditions.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Beyond the Cut Hunter: A Historical Epidemiology of HIV Beginnings in Central Africa

International audienceIn the absence of direct evidence, an imagined ''cut hunter'' stands in for the index patient of pandemic HIV/AIDS. During the early years of colonial rule, this explanation goes, a hunter was cut or injured from hunting or butchering a chimpanzee infected with simian immunodeficiency virus, resulting in the first sustained human infection with the virus that would emerge as HIV-1M. We argue here that the ''cut hunter'' relies on a historical misunderstanding and ecological oversimplification of human-chimpanzee (Pan Tro-glodytes troglodytes) interactions that facilitated pathogenic transmission. This initial host shift cannot explain the beginnings of the HIV/AIDS pandemic. Instead, we must understand the processes by which the virus became transmissible, possibly between Sangha basin inhabitants and ultimately reached Kinshasa. A historical epidemiology of the late nineteenth and twentieth centuries, provides a much-needed corrective to the major shortcomings of the cut hunter. Based on 62 oral historical interviews conducted in southeastern Cameroon and archival research, we show that HIV emerged from ecological, economic, and socio-political transformations of the late nineteenth and twentieth centuries. The gradual imposition of colonial rule built on and reoriented ecologies and economies, and altered older patterns of mobility and sociality. Certain changes may have contributed to the initial viral host shift, but more importantly, facilitated the adaptation of HIV-1M to human-to-human transmission. Our evidence suggests that the most critical changes occurred after 1920. This argument has important implications for public health policy, underscoring recent work emphasizing alternative pathways for zoonotic spillovers into human beings