49 research outputs found

    Valorisation de la Carte des Sols dans un cadre inattendu - Le tourisme à caractère scientifique

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    Patrimoine géologique et pédologique en Province de Namur - 500 millions d'années de façonnement de notre paysag

    Complete mitochondrial genome of the speckled dace \u3ci\u3eRhinichthys osculus\u3c/i\u3e, a widely distributed cyprinid minnow of western North America

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    The speckled dace Rhinichthys osculus (order Cypriniformes), also known as the carpita pinta, is a small cyprinid minnow native to western North America. Here, we report the sequencing of the full mitochondrial genome (mitogenome) of R. osculus from a male fish collected from the Amargosa River Canyon in eastern California, USA. The assembled mitogenome is 16 658 base pair (bp) nucleotides, and encodes 13 protein-coding genes, and includes both a 12S and a 16S rRNA, 22 tRNAs, and a 985 bp D-loop control region. Mitogenome synteny reflects that of other Ostariophysian fishes with the majority of genes and RNAs encoded on the heavy strand (H-strand) except nd6, tRNA-Gln, tRNA-Ala, tRNA-Asn, tRNA-Cys, tRNA-Tyr, tRNA-Ser, tRNA-Glu, and tRNA-Pro. The availability of this R. osculus mitochondrial genome – the first complete mitogenome within the lineage of Rhinichthys riffle daces – provides a foundation for resolving evolutionary relationships among morphologically differentiated populations of R. osculus

    Numerical optimization of integrating cavities for diffraction-limited millimeter-wave bolometer arrays

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    Far-infrared to millimeter-wave bolometers designed to make astronomical observations are typically encased in integrating cavities at the termination of feedhorns or Winston cones. This photometer combination maximizes absorption of radiation, enables the absorber area to be minimized, and controls the directivity of absorption, thereby reducing susceptibility to stray light. In the next decade, arrays of hundreds of silicon nitride micromesh bolometers with planar architectures will be used in ground-based, suborbital, and orbital platforms for astronomy. The optimization of integrating cavity designs is required for achieving the highest possible sensitivity for these arrays. We report numerical simulations of the electromagnetic fields in integrating cavities with an infinite plane-parallel geometry formed by a solid reflecting backshort and the back surface of a feedhorn array block. Performance of this architecture for the bolometer array camera (Bolocam) for cosmology at a frequency of 214 GHz is investigated. We explore the sensitivity of absorption efficiency to absorber impedance and backshort location and the magnitude of leakage from cavities. The simulations are compared with experimental data from a room-temperature scale model and with the performance of Bolocam at a temperature of 300 mK. The main results of the simulations for Bolocam-type cavities are that (1) monochromatic absorptions as high as 95% are achievable with <1% cross talk between neighboring cavities, (2) the optimum absorber impedances are 400 Ω/sq, but with a broad maximum from ~150 to ~700 Ω/sq, and (3) maximum absorption is achieved with absorber diameters ≥1.5λ. Good general agreement between the simulations and the experiments was found

    Bolocam: a millimeter-wave bolometric camera

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    We describe the design of Bolocam, a bolometric camera for millimeter-wave observations at the Caltech Submillimeter Observatory. Bolocam will have 144 diffraction-limited detectors operating at 300 mK, an 8 arcminute field of view, and a sky noise limited NEFD of approximately 35 mJy Hz^(-1/2) per pixel at λ = 1.4 mm. Observations will be possible at one of (lambda) equals 1.1., 1.4, or 2.1 mm per observing run. The detector array consists of sensitive NTD Ge thermistors bonded to silicon nitride micromesh absorbers patterned on a single wafer of silicon. This is a new technology in millimeter-wave detector array construction. To increase detector packing density, the feed horns will be spaced by 1.26 fλ (at λ = 1.4 mm), rather than the conventional 2fλ . DC stable read out electronics will enable on-the-fly mapping and drift scanning. We will use Bolocam to map Galactic dust emission, to search for protogalaxies, and to observe the Sunyaev- Zel'dovich effect toward galaxy clusters

    Current status of Bolocam: a large-format millimeter-wave bolometer camera

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    We describe the design and performance of Bolocam, a 144-element, bolometric, millimeter-wave camera. Bolocam is currently in its commissioning stage at the Caltech Submillimeter Observatory. We compare the instrument performance measured at the telescope with a detailed sensitivity model, discuss the factors limiting the current sensitivity, and describe our plans for future improvements intended to increase the mapping speed

    Women’s sexual scripting in the context of universal access to antiretroviral treatment—findings from the HPTN 071 (PopART) trial in South Africa

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    Background HIV treatment-based prevention modalities present new opportunities for women to make decisions around sex, intimacy, and prevention. The Universal test and treat (UTT) strategy, where widespread HIV testing is implemented and all people with HIV can access treatment, has the potential to change how sex is understood and HIV prevention incorporated into sexual relationships. We use the frame of sexual scripting to explore how women attribute meaning to sex relative to UTT in an HIV prevention trial setting. Exploring women’s sexual narratives, we explored how HIV prevention feature in the sexual scripts for women who had access to UTT in South Africa (prior to treatment guideline changes) and increased HIV prevention messaging, compared to places without widespread access to HIV testing and immediate access to treatment. Methods We employed a two-phased thematic analysis to explore longitudinal qualitative data collected from 71 women (18–35 years old) between 2016 and 2018 as part of an HIV prevention trial in the Western Cape Province, South Africa. Of the participants, 58/71 (82%) were from intervention communities while 13/71 (18%) lived in control communities without access to UTT. Twenty participants self-disclosed that they were living with HIV. Results We found no narrative differences between women who had access to UTT and those who did not. HIV and HIV prevention, including treatment-based prevention modalities, were largely absent from women’s thinking about sex. In their scripts, women idealised romantic sex, positioned sex as ‘about relationships’, and described risky sex as ‘other’. When women were confronted by HIV risk (for example, when a partner disclosed his HIV-positive status) this created a point of disjuncture between this new perception of risk and their accepted relationship scripts. Conclusion These findings suggest that HIV-negative women did not include their partners’ use of antiretroviral therapy in their sexual partnership choices. For these women, the preventive benefits of UTT are experienced passively—through community-wide viral suppression—rather than through their own behaviour change explicitly related to the availability of treatment as prevention. We propose that prevention-based modalities should be made available and supported and framed as an intervention to promote relationship well-being

    Current status of Bolocam: a large-format millimeter-wave bolometer camera

    Get PDF
    We describe the design and performance of Bolocam, a 144-element, bolometric, millimeter-wave camera. Bolocam is currently in its commissioning stage at the Caltech Submillimeter Observatory. We compare the instrument performance measured at the telescope with a detailed sensitivity model, discuss the factors limiting the current sensitivity, and describe our plans for future improvements intended to increase the mapping speed
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