113 research outputs found
Misexpression of a transcriptional repressor candidate provides a molecular mechanism for the suppression of awns by Tipped 1 in wheat.
Awns are bristle-like structures formed at the tip of the lemma on the florets of some cereal grasses. Wild-type wheat is awned, but awnletted and awnless variants have been selected and nowadays all forms are cultivated. In this study, we dissected the genetic control underlying variation of this characteristic feature by association mapping in a large panel of 1110 winter wheat cultivars of worldwide origin. We identified the B1 (Tipped 1) locus on chromosome 5A as the major determinant of awnlessness globally. Using a combination of fine-mapping and expression analysis, we identified a putative C2H2 zinc finger protein with an EAR domain, characteristic of transcriptional repressors, as a likely candidate for Tipped 1. This gene was found to be up-regulated in awnless B1 compared with awned b1 plants, indicating that misexpression of this transcriptional regulator may contribute to the reduction of awn length in B1 plants. Taken together, our study provides an entry point towards a better molecular understanding of the evolution of morphological features in cereals through selection and breeding
Standardizing data reporting in the research community to enhance the utility of open data for SARS-CoV-2 wastewater surveillance
SARS-CoV-2 RNA detection in wastewater is being rapidly developed and adopted as a public health monitoring tool worldwide. With wastewater surveillance programs being implemented across many different scales and by many different stakeholders, it is critical that data collected and shared are accompanied by an appropriate minimal amount of meta-information to enable meaningful interpretation and use of this new information source and intercomparison across datasets. While some databases are being developed for specific surveillance programs locally, regionally, nationally, and internationally, common globally-adopted data standards have not yet been established within the research community. Establishing such standards will require national and international consensus on what meta-information should accompany SARS-CoV-2 wastewater measurements. To establish a recommendation on minimum information to accompany reporting of SARS-CoV-2 occurrence in wastewater for the research community, the United States National Science Foundation (NSF) Research Coordination Network on Wastewater Surveillance for SARS-CoV-2 hosted a workshop in February 2021 with participants from academia, government agencies, private companies, wastewater utilities, public health laboratories, and research institutes. This report presents the primary two outcomes of the workshop: (i) a recommendation on the set of minimum meta-information that is needed to confidently interpret wastewater SARS-CoV-2 data, and (ii) insights from workshop discussions on how to improve standardization of data reporting
Atmospheric hydrogen sulfide over the equatorial Pacific (SAGA 3)
Atmospheric H2S concentrations were measured over the equatorial Pacific on leg 1 of the third Soviet-American Gases and Aerosols (SAGA 3) cruise during February and March 1990. Five N-S transects were made across the equator between Hawaii and American Samoa. The concentrations ranged from below the detection limit of 0.4 ± 0.5 (1 σ) to 14.4 ppt with an average value of 3.6 ± 2.3 ppt (1σ, n= 72). The highest concentrations were found on the easternmost two transects just south of the equator. The average concentration of 3.6 ppt observed on this cruise is the lowest reported value for background atmospheric H2S over the tropical oceans. A lack of correlation between 222Rn and H2S rules out a significant continental source. Model calculations indicate that the oceanic source of H2S in this region is in the range of 9 to 21 × 10−8 mol m−2 d−1. From this flux the concentration of free sulfide (H2S + S= ) in the surface mixed layer of the ocean is estimated to be in the range of 32 to 67 pmol L−1. In the atmosphere the oxidation of H2S produces SO2 at a rate of 2.1 to 4.4 × 10−11 mol m−3 d−1 which is only a small fraction of that estimated from the oxidation of dimethyl sulfide (DMS) in this region. A diurnal cycle was not observed in the H2S data recorded during this cruise
The James Webb Space Telescope Mission: Optical Telescope Element Design, Development, and Performance
The James Webb Space Telescope (JWST) is a large, infrared space telescope
that has recently started its science program which will enable breakthroughs
in astrophysics and planetary science. Notably, JWST will provide the very
first observations of the earliest luminous objects in the Universe and start a
new era of exoplanet atmospheric characterization. This transformative science
is enabled by a 6.6 m telescope that is passively cooled with a 5-layer
sunshield. The primary mirror is comprised of 18 controllable, low areal
density hexagonal segments, that were aligned and phased relative to each other
in orbit using innovative image-based wavefront sensing and control algorithms.
This revolutionary telescope took more than two decades to develop with a
widely distributed team across engineering disciplines. We present an overview
of the telescope requirements, architecture, development, superb on-orbit
performance, and lessons learned. JWST successfully demonstrates a segmented
aperture space telescope and establishes a path to building even larger space
telescopes.Comment: accepted by PASP for JWST Overview Special Issue; 34 pages, 25
figure
- …