•We determined the shape of Bennu from radar and lightcurve observations.•We used the Arecibo and Goldstone radars to select a spacecraft mission target.•Combining radar and lightcurve data makes ...shape modeling simpler and more robust.•Asteroid Bennu has a smoother surface than most spacecraft-visited asteroids.•Bennu has a shape similar to binary near-Earth asteroids.
We determine the three-dimensional shape of near-Earth Asteroid (101955) Bennu based on radar images and optical lightcurves. Bennu was observed both in 1999 at its discovery apparition, and in 2005 using the 12.6-cm radar at the Arecibo Observatory and the 3.5-cm radar at the Goldstone tracking station. Data obtained in both apparitions were used to construct a shape model of this object. Observations were also obtained at many other wavelengths to characterize this object, some of which were used to further constrain the shape modeling. The lightcurve data, along with an initial determination of the rotation period derived from them, simplified and improved the shape modeling.
Below we briefly describe the observations and shape modeling process. We discuss the shape model and the implications for the possible formation and evolution of this object. We also describe the importance and limitations of the shape model in view of the fact that this object is the target of the OSIRIS-REx spacecraft mission.
Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological ...niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.
In a prospective service evaluation of 125 consecutive patients with obstructive sleep apnea syndrome (apnea-hypopnea index 4, or >4% oxygen desaturation index, >7.5 events/h, and symptoms of daytime ...tiredness and hypersomnolence) offered continuous positive airway pressure (CPAP), ESS was measured at baseline and follow-up (3-months post-CPAP initiation). ...few patients reported deterioration in their daytime sleepiness; hence, our data estimate the minimum clinically important improvement rather than the true MCID of the ESS. A multicentre randomised controlled trial and economic evaluation of continuous positive airway pressure for the treatment of obstructive sleep apnoea syndrome in older people: PREDICT.
Brassinosteroids (BRs) regulate plant growth, development, and stress responses by activating the core transcription factor BRI1-EMS-SUPPRESSOR1 (BES1), whose degradation occurs through the ...proteasome and autophagy pathways. The E3 ubiquitin ligase(s) that modify BES1 for autophagy-mediated degradation remain to be fully defined. Here, we identified an F-box family E3 ubiquitin ligase named BES1-ASSOCIATED F-BOX1 (BAF1) in Arabidopsis thaliana. BAF1 interacts with BES1 and mediates its ubiquitination and degradation. Our genetic data demonstrated that BAF1 inhibits BR signaling in a BES1-dependent manner. Moreover, BAF1 targets BES1 for autophagic degradation in a selective manner. BAF1-triggered selective autophagy of BES1 depends on the ubiquitin binding receptor DOMINANT SUPPRESSOR OF KAR2 (DSK2). Sucrose starvation-induced selective autophagy of BES1, but not bulk autophagy, was significantly compromised in baf1 mutant and BAF1-ΔF (BAF1 F-box decoy) overexpression plants, but clearly increased by BAF1 overexpression. The baf1 and BAF1-ΔF overexpression plants had increased BR-regulated growth but were sensitive to long-term sucrose starvation, while BAF1 overexpression plants had decreased BR-regulated growth but were highly tolerant of sucrose starvation. Our results not only established BAF1 as an E3 ubiquitin ligase that targets BES1 for degradation through selective autophagy pathway, but also revealed a mechanism for plants to reduce growth during sucrose starvation.
We conducted a population-based case-control study to determine the magnitude of the excess risk of tuberculosis in those infected with the human immunodeficiency virus (HIV) in Seattle-King County, ...Washington. Patients were 39 of the 54 cases of tuberculosis in white and in black (including Hispanic) men aged 20 through 49 reported to the Seattle-King County Department of Public Health between January 1986 and June 1988. Controls were 34 white and black men of similar age who had tuberculin testing as a condition of employment. Eleven (28 percent) of the 39 patients with tuberculosis and 2 (6 percent) of the 34 controls tested positive for antibody to HIV (odds ratio adjusted for age and race = 6.2; 95 percent confidence interval 1.2 to 31.9). Calculation of the etiologic fashion indicated that 24 percent of the tuberculosis cases in this population of young black and white men were attributable to concurrent HIV infection.
The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events ...with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.
During an infection the immune system produces pathogen-specific antibodies. These antibody repertoires become specific to the history of infections and represent a rich source of diagnostic markers. ...However, the specificities of these antibodies are mostly unknown. Here, using high-density peptide arrays we examined the human antibody repertoires of Chagas disease patients. Chagas disease is a neglected disease caused by Trypanosoma cruzi, a protozoan parasite that evades immune mediated elimination and mounts long-lasting chronic infections. We describe a proteome-wide search for antigens, characterised their linear epitopes, and show their reactivity on 71 individuals from diverse human populations. Using single-residue mutagenesis we revealed the core functional residues for 232 of these epitopes. Finally, we show the diagnostic performance of identified antigens on challenging samples. These datasets enable the study of the Chagas antibody repertoire at an unprecedented depth and granularity, while also providing a rich source of serological biomarkers.
The SNO+ Experiment Anselmo, L; Arushanova, E; Asahi, S ...
arXiv.org,
08/2021
Paper, Journal Article
Odprti dostop
The SNO+ experiment is located 2 km underground at SNOLAB in Sudbury, Canada. A low background search for neutrinoless double beta (\(0\nu\beta\beta\)) decay will be conducted using 780 tonnes of ...liquid scintillator loaded with 3.9 tonnes of natural tellurium, corresponding to 1.3 tonnes of \(^{130}\)Te. This paper provides a general overview of the SNO+ experiment, including detector design, construction of process plants, commissioning efforts, electronics upgrades, data acquisition systems, and calibration techniques. The SNO+ collaboration is reusing the acrylic vessel, PMT array, and electronics of the SNO detector, having made a number of experimental upgrades and essential adaptations for use with the liquid scintillator. With low backgrounds and a low energy threshold, the SNO+ collaboration will also pursue a rich physics program beyond the search for \(0\nu\beta\beta\) decay, including studies of geo- and reactor antineutrinos, supernova and solar neutrinos, and exotic physics such as the search for invisible nucleon decay. The SNO+ approach to the search for \(0\nu\beta\beta\) decay is scalable: a future phase with high \(^{130}\)Te-loading is envisioned to probe an effective Majorana mass in the inverted mass ordering region.
A potentially productive triangular arrangement among Russia, Ukraine, and the United States emerged in 1994 from efforts to constrain nuclear weapons diffusion. By 2001, this promising initiative ...was nearly moribund, owing to the inability or unwillingness of the parties to fulfill the commitments of subsequent agreements. The domestic and external causes of this failure are many and clear. Yet the advantages to each of reengaging in a trilateral relationship are also plain. This means fulfilling their unfinished agenda by learning from past mistakes, adopting realistic premises and goals, and pursuing 'bottom up' as well as 'top down' strategies.
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