211 research outputs found

    Pathogen Transmission Techniques and Genotypic Resistance to Disease in the Threatened Coral, Acropora cervicornis

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    Unprecedented population losses of the staghorn coral, Acropora cervicornis, since the 1970s have been attributed primarily to disease. Although a positive linear relationship between disease prevalence and increased water temperature has been described, the pathogen(s) causing disease and whether they are spread through the water or vectors is still poorly understood. Additionally, an increase in disease outbreaks and severity has provided an urgent need to identify natural genotypic resistance to disease in Caribbean acroporids. Studies to date have explored a variety of pathogen transmission methods, but prior to this study, there has been no examination of differences among common techniques. I investigated pathogen transmission and resistance to development of the disease known as rapid-tissue loss (RTL) in 11 different genotypes by comparing two common transmission methods (direct contact vs. waterborne). Additionally, I investigated changes in tissue condition over a 9-day acclimation period to determine the potential effect of acclimation on disease susceptibility. Overall, disease was significantly higher in the direct contact treatment, though resulting disease varied greatly by genotype, with only one genotype appearing resistant to developing disease. Acclimation time influenced tissue condition with a significant decline in condition occurring from day zero to day two, but significant improvements in surface body wall parameters were observed from days two to nine. These results highlight the differences between disease transmission methods and demonstrate the importance of selecting an appropriate transmission method and acclimation period for future studies

    IceSat 2 ATLAS Photon-Counting Receiver - Initial On-Orbit Performance

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    Photon-counting receivers are deployed on the NASA Ice, Cloud and land Elevation Satellite-2 (ICESat2) Advance Topographic Laser Altimeter System (ATLAS). The ATLAS laser altimeter design has total six ground tracks with three strong and three weak tracks. The strong track has nominally 4 times more laser power than the weak track. The receiver is operated in photon counting mode. There are 16 photon-counting channels for each strong track and 4 photon-counting channels for each weak track. Hamamatsu photomultiplier with a 4x4-array anode was used as photon counting detector. This receiver design has high counting efficiency (>15%) at 532 nm, low dark count rate (<400 counts per second), low jitter (less than 285ps), short dead time (<3 ns), long lifetime under large solar background radiation, radiation harden for space operation, and ruggedized for survives the harsh vibration during the launch. In this paper, we will present the initial on-orbit performance of this photon-counting receiver

    A measurement of the millimetre emission and the Sunyaev–Zel'dovich effect associated with low-frequency radio sources

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    We present a statistical analysis of the millimetre-wavelength properties of 1.4 GHz-selected sources and a detection of the Sunyaev–Zel'dovich (SZ) effect associated with the haloes that host them. We stack data at 148, 218 and 277 GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4 GHz. The thermal SZ effect associated with the haloes that host the AGN is detected at the 5σ level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass haloes (average M_(200) ≈ 10^(13) M⊙ h^(−1)_(70) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous haloes. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyse the contribution of radio sources to the angular power spectrum of the cosmic microwave background

    Robotic Sacral Colpopexy Using Autologous Fascia Lata Compared with Mesh

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    Objective: The objective is to compare robotic sacral colpopexy (RSC) utilizing autologous fascia lata with RSC with synthetic mesh in the treatment of pelvic organ prolapse (POP). Methods: We performed a prospective nonrandomized case comparison trial at a single institution. We compared RSC utilizing either synthetic mesh or autologous fascia lata in women with symptomatic POP, stages II through IV. The primary outcome was anatomic prolapse recurrence determined by the Pelvic Organ Prolapse Quantification (POP-Q) examination. Secondary outcomes included patient-reported outcomes such as the Urogenital Distress Inventory-6 (UDI-6) and Incontinence Impact Questionnaire-7 (IIQ-7). Complications were also recorded and categorized using the Clavien–Dindo (CD) system. The hypothesis is that autologous fascia lata would provide equivalent anatomic and patient-reported outcomes compared with mesh while eliminating mesh-related complications. Results: Sixty-four women underwent RSC with 19 (29.7%) receiving fascia lata graft. The overall operative time was greater in the fascia lata group with mean fascia lata harvest time of 24.8 ± 7.4 minutes. Intragroup comparisons of the fascia and mesh groups demonstrated significant improvement in pelvic measurements as well as patient-reported outcomes. Intergroup comparison demonstrated equivalent success rates at 12.1 ± 8.7 months follow-up. There was one apical failure in the fascia lata RSC group; however, the difference was not statistically significant (p = 0.30). Significant complications in the fascia lata harvest group included two CD-II and one CD-IIIb. In the mesh group there was one mesh erosion requiring surgical excision (CD-IIIb). Conclusion: This is the first comparison between RSC with autologous fascia lata and mesh. Short-term anatomic outcomes were similar with autologous fascia lata use without the risk of mesh erosion. Morbidity from graft harvest site was not trivial. These results emphasize the need for a randomized controlled trial

    Vitamin D in the prevention of exacerbations of asthma in preschoolers (DIVA): Protocol for a multicentre randomised placebo-controlled triple-blind trial

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    Introduction Preschoolers have the highest rate of emergency visits and hospitalisations for asthma exacerbations of all age groups, with most triggered by upper respiratory tract infections (URTIs) and occurring in the fall or winter. Vitamin D insufficiency is highly prevalent in Canadian preschoolers with recurrent asthma exacerbations, particularly in winter. It is associated with more URTIs and, in patients with asthma, more oral corticosteroid (OCS) use. Although evidence suggests that vitamin D supplements significantly decrease URTIs and asthma exacerbations requiring OCS, there is insufficient data in preschoolers. This study aims to determine the impact of vitamin D 3 supplementation on exacerbations requiring OCS, in preschoolers with recurrent URTI-induced asthma exacerbations. Methods and analysis This is a phase III, randomised, triple-blind, placebo-controlled, parallel-group multicentre trial of vitamin D 3 supplementation in children aged 1-5 years, with asthma triggered by URTIs and a recent history of frequent URTIs and OCS use. Children (n=865) will be recruited in the fall and early winter and followed for 7 months. They will be randomised to either the (1) intervention: two oral boluses of 100 000 international unit (IU) vitamin D 3 (3.5 months apart) with 400 IU vitamin D 3 daily; or (2) control: identical placebo boluses with daily placebo. The primary outcome is the number of exacerbations requiring OCS per child, documented by medical and pharmacy records. Secondary outcomes include number of laboratory-confirmed viral URTIs, exacerbation duration and severity, parent functional status, healthcare use, treatment deintensification, cost and safety. Ethics and dissemination This study has received ethical approval from all sites. Results will be disseminated via international conferences and manuscripts targeting paediatricians and respirologists, and to families of asthmatic children via our Quebec parents-partners outreach programme. If proven effective, findings may markedly influence the management of URTI-induced asthma in high-morbidity preschoolers and could be directly implemented into practice with an update to clinical guidelines. Trial registration number NCT03365687

    Clinician perception of care at the end of life in a quaternary neonatal intensive care unit

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    IntroductionCare for neonates at the end of life (EOL) is often challenging for families and medical teams alike, performed suboptimally, and requires an experienced and compassionate clinician. Much literature exists on adult and pediatric EOL care, but limited studies examine the neonatal process.MethodsWe aimed to describe clinicians' experiences around EOL care in a single quaternary neonatal intensive care unit as we implemented a standard guideline using the Pediatric Intensive Care Unit-Quality of Dying and Death 20 tool.ResultsSurveys were completed by 205 multidisciplinary clinicians over three time periods and included 18 infants at EOL. While most responses were high, a meaningful minority were below goal (&lt;8 on 0–10 scale) for troubling symptom management, conflict between parents and staff, family access to resources, and parent preparation of symptoms. Comparison between Epochs revealed improvement in one symptom management and four communication categories. Satisfaction scores related to education around EOL were better in later Epochs. Neonatal Pain, Agitation, and Sedation Scale scores were low, with few outliers.DiscussionThese findings can guide those aiming to improve processes around neonatal EOL by identifying areas with the greatest challenges (e.g., conflict management) and areas that need further study (e.g., pain management around death)

    A measurement of the millimetre emission and the Sunyaev-Zel'dovich effect associated with low-frequency radio sources

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    We present a statistical analysis of the millimetre-wavelength properties of 1.4GHz-selected sources and a detection of the Sunyaev–Zel’dovich (SZ) effect associated with the haloes that host them. We stack data at 148, 218 and 277GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4GHz. The thermal SZ effect associated with the haloes that host the AGN is detected at the 5σ level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass haloes (average M 200 ≈ 10 13 M. h −1 70 ) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous haloes. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyse the contribution of radio sources to the angular power spectrum of the cosmic microwave background

    A Measurement of the Millimeter Emission and the Sunyaev-Zel'dovich Effect Associated with Low-Frequency Radio Sources

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    We present a statistical analysis of the millimeter-wavelength properties of 1.4 GHz-selected sources and a detection of the Sunyaev-Zel'dovich effect associated with the halos that host them. We stack data at 148, 218 and 277 GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4 GHz. The thermal Sunyaev-Zel'dovich (SZ) effect associated with the halos that host the AGN is detected at the 5 sigma level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass halos (average M(sub 200) approximately equals 10(sup 13) solar mass h(sub 70)(exp 1) ) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous halos. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyze the contribution of radio sources to the angular power spectrum of the cosmic microwave background

    A Measurement of the Millimeter Emission and the Sunyaev-zel'dovich Effect Associated with Low-frequency Radio Sources

    Get PDF
    We present a statistical analysis of the millimeter-wavelength properties of 1.4 GHz-selected sources and a detection of the Sunyaev-Zel'dovich Effect associated with the halos that host them. The Atacama Cosmology Telescope (ACT) has conducted a survey at 148 GHz, 218 GHz and 277 GHz along the celestial equator. Using samples of radio sources selected at 1.4 GHz from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) Survey and the National Radio Astronomy Observatory Very Large Array Sky Survey (NVSS), we measure the stacked 148, 218 and 277 GHz flux densities for sources with 1.4 GHz flux densities ranging from 5 to 200 mJy. At these flux densities, the radio source population is dominated by active galactic nuclei (AGN), with both steep and at spectrum populations, which have combined radio-to-millimeter spectral indices ranging from 0.5 to 0.95, reecting the prevalence of steep spectrum sources at high flux densities and the presence of at spectrum sources at lower flux densities. The thermal Sunyaev-Zelapos;dovich (SZ) eect associated with the halos that host the AGN is detected at the 5 level through its spectral signature. When we compare the SZ eect with weak lensing measurements of radio galaxies, we find that the relation between the two is consistent with that measured by Planck for local bright galaxies. We present a detection of the SZ eect in some of the lowest mass halos (average M(sub 200) approx. equals 10(exp 13) solar M h(sup-1) (sub 70) ) studied to date. This detection is particularly important in the context of galaxy evolution models, as it confirms that galaxies with radio AGN also typically support hot gaseous halos. With Herschel* observations, we show that the SZ detection is not significantly contaminated by dusty galaxies or by dust associated with the AGN or galaxies hosting the AGN. We show that 5 mJy < S(sub 1:4) < 200 mJy radio sources contribute l(l +1)C(sub l)/(2 pi ) = 0:37+/- 0:03 micro K(exp 2) to the angular power spectrum at l = 3000 at 148 GHz, after accounting for the SZ effect associated with their host halos
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