The CHinense Exoplanet Searching Program from Antarctica is a ground-based wide-field photometric survey using the AST3 and CSTAR telescopes located at Dome A, Antarctica. Blessed with the unparalleled observing conditions on the highest point of the Antarctic plateau, three remotely controlled, fully automatic telescopes (AST3-I, AST3-II, and CSTAR-II) carried out continuous high-precision photometric surveys through the polar nights of 2016 and 2017. During the observing seasons of 2016, a total of 26,578 light curves were obtained for stars within the area of the southern continuous viewing zone of TESS, covering an i-band magnitude range from 7.5 to 15. At m(i) = 10, photometric precision reaches similar to 2 mmag, allowing possible discoveries of sub-Jupiter-size exoplanets. Here we report 20 stellar flares with i-band energies larger than 10(34) erg detected in the 2016 data set of AST3-II, all from different sources. We model the stellar flares and calculate the durations, amplitudes, energies, and skewnesses. The flare properties and the stellar properties of their sources are presented in this work.

Luminous z Luminous z >= 7 quasars provide direct probes of the evolution of supermassive black holes (SMBHs) and the intergalactic medium (IGM) during the epoch of reionization (EoR). The Ly alpha damping wing absorption imprinted by neutral hydrogen in the IGM can be detected in a single EoR quasar spectrum, allowing the measurement of the IGM neutral fraction toward that line of sight. However, damping wing features have only been detected in two z > 7 quasars in previous studies. In this paper, we present new high-quality optical and near-infrared spectroscopy of the z = 7.00 quasar DES J025216.64-050331.8 obtained with Keck/Near-Infrared Echellette Spectrometer and Gemini/GMOS. By using the Mg II single-epoch virial method, we find that it hosts a (1.39 +/- 0.16) x 10(9) M-circle dot SMBH accreting at an Eddington ratio of lambda(Edd) = 0.7 +/- 0.1, consistent with the values seen in other luminous z similar to 7 quasars. Furthermore, the Lya region of the spectrum exhibits a strong damping wing absorption feature. The lack of associated metal absorption in the quasar spectrum indicates that this absorption is imprinted by a neutral IGM. Using a state-of-the-art model developed by Davies et al., we measure a volumeaveraged neutral hydrogen fraction at z = 7 of < x(H I)> = 0.70(-0.23)(+0.20)

X-ray emission from quasars has been detected up to redshift z = 7.5, although only limited to a few objects at z > 6.5. In this work, we present new Chandra observations of five z > 6.5 quasars. By combining with archival Chandra observations of six additional z > 6.5 quasars, we perform a systematic analysis on the X-ray properties of these earliest accreting supermassive black holes (SMBHs). We measure the black hole masses, bolometric luminosities (L-bol), Eddington ratios (lambda(Edd)), emission line properties, and infrared luminosities (L-IR) of these quasars using infrared and submillimeter observations. Correlation analysis indicates that the X-ray bolometric correction (the factor that converts from X-ray luminosity to bolometric luminosity) decreases with increasing L-bol, and that the UV/optical-to-X-ray ratio, alpha(ox), strongly correlates with L-2500 A, and moderately correlates with lambda(Edd) and blueshift of C iv emission lines. These correlations are consistent with those found in lower-z quasars, indicating quasar accretion physics does not evolve with redshift. We also find that L-IR does not correlate with L2-10 keV in these luminous distant quasars, suggesting that the ratio of the SMBH growth rate and their host galaxy growth rate in these early luminous quasars are different from those of local galaxies. A joint spectral analysis of the X-ray detected z > 6.5 quasars yields an average X-ray photon index of Gamma = 2.32(-0.30)(+0.31), steeper than that of low-z quasars. By comparing it with the Gamma - lambda(Edd) relation, we conclude that the steepening of Gamma for quasars at z > 6.5 is mainly driven by their higher Eddington ratios.

Carbohydrates (sugars) are an essential energy-source for all life forms. They take a significant share of our daily consumption and are used for biofuel production as well. However, sugarcane and sugar beet are the only two crop plants which are used to produce sugar in significant amounts. Here, we have discovered and fine-tuned a phenomenon in rice which leads them to produce sugary-grain. We knocked-out GCS1 genes in rice by using CRISPR technology, which led to fertilization failure and pollen tube-dependent ovule enlargement morphology (POEM) phenomenon. Apparently, the POEMed-like rice ovule ('endosperm-focused') can grow near-normal seed-size unlike earlier observations in Arabidopsis in which gcs1 ovules ('embryo-focused') were aborted quite early. The POEMed-like rice ovules contained 10-20% sugar, with extremely high sucrose content (98%). Trancriptomic analysis revealed that the osgcs1 ovules had downregulation of starch biosynthetic genes, which would otherwise have converted sucrose to starch. Overall, this study shows that pollen tube content release is sufficient to trigger sucrose unloading at rice ovules. However, successful fertilization is indispensable to trigger sucrose-starch conversion. These findings are expected to pave the way for developing novel sugar producing crops suited for diverse climatic regions.

Background Certain membrane-associated arabinogalactan-proteins (AGPs) with lysine-rich sub-domains participate in plant growth, development and resistance to stress. To complement fluorescence imaging of such molecules when tagged and introduced transgenically to the cell periphery and to extend the groundwork for assessing molecular structure, some behaviours of surface-spread AGPs were visualized at the nanometre scale in a simplified electrostatic environment.

Gene expression data from isolated endodermal cells after roots were treated with 140 mM NaCl for 32 hour Data quality was examined using the signal distribution of Affymetrix built-in controls (Spike-in and hybridization controls) using Expression Console software (Affymetrix) and AffyQCReport. GCRMA in R/Bioconductor was used for data normalization.

Gene expression data from isolated endodermal cells after roots were treated with 140 mM NaCl for 8 hour Data quality was examined using the signal distribution of Affymetrix built-in controls (Spike-in and hybridization controls) using Expression Console software (Affymetrix) and AffyQCReport. GCRMA in R/Bioconductor was used for data normalization.

Gene expression data from isolated stele cells after roots were treated with 140 mM NaCl for 3 hour Data quality was examined using the signal distribution of Affymetrix built-in controls (Spike-in and hybridization controls) using Expression Console software (Affymetrix) and AffyQCReport. GCRMA in R/Bioconductor was used for data normalization.

Gene expression data from isolated endodermal cells after roots were treated with 140 mM NaCl for 48 hour Data quality was examined using the signal distribution of Affymetrix built-in controls (Spike-in and hybridization controls) using Expression Console software (Affymetrix) and AffyQCReport. GCRMA in R/Bioconductor was used for data normalization.