A black hole X-ray binary produces hard X-ray radiation from its corona and disk when the accreting matter heats up. During an outburst, the disk and corona co-evolves with each other. However, such an evolution is still unclear in both its geometry and dynamics. Here we report the unusual decrease of the reflection fraction in MAXI J1820+070, which is the ratio of the coronal intensity illuminating the disk to the coronal intensity reaching the observer, as the corona is observed to contrast during the decay phase. We postulate a jet-like corona model, in which the corona can be understood as a standing shock where the material flowing through. In this dynamical scenario, the decrease of the reflection fraction is a signature of the corona’s bulk velocity. Our findings suggest that as the corona is observed to get closer to the black hole, the coronal material might be outflowing faster.

Supplementary data are available at Bioinformatics online.

Abstract. The Taklimakan Desert is a main and continuous source of Asian dust particles causing significant direct radiative effects, which are commonly quantified by the aerosol solar radiative forcing (ASRF). To improve the accuracy of estimates of dust ASRF, the Dust Aerosol Observation-Kashi (DAO-K) campaign was carried out near the Taklimakan Desert in April 2019. The objective of the DAO-K campaign is to provide crucial parameters needed for the calculation of ASRF, such as dust optical and microphysical properties, vertical distribution, and surface albedo. The ASRF was calculated using radiative transfer (RT) simulations based on the observed aerosol parameters, additionally considering the measured atmospheric profiles and diurnal variations of surface albedo. As a result, daily average values of ASRF of −19 W m−2 at the top of the atmosphere and −36 W m−2 at the bottom of the atmosphere were derived from the simulations conducted during the DAO-K campaign. Furthermore, the Weather Research and Forecasting model with Chemistry (WRF-Chem), with assimilation of measurements of the aerosol optical depth and particulate matter (PM) mass concentrations of particles with aerodynamic diameter smaller than 2.5 µm (PM2.5) and 10 µm (PM10), is employed to estimate the dust ASRF for comparison. The results of the ASRF simulations (RT and WRF-Chem) were evaluated using ground-based downward solar irradiance measurements, which have confirmed that the RT simulations are in good agreement with simultaneous observations, whereas the WRF-Chem estimations reveal obvious discrepancies with the solar irradiance measurements.

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Butterflies use multiple signals, including visual, olfactory and tactile cues, to identify same- and opposite-sex individuals during courtship. In this study of the sexually dimorphic butterfly Cethosia cyane cyane, we explored the roles of visual and olfactory cues in conspecific mate recognition during courtship. Our results showed that males took the initiative in actively chasing females during courtship using only visual cues. Males could distinguish the gender of conspecifics using visual cues alone. The size and color of the wings differ significantly between the sexes. Behavioral assays showed that males visually recognized females not by wing size, but by their sexually specific wing color. The movement pattern of the model also exerted some influence on male courtship chasing behavior. A total of 21 volatiles were detected in the bodies of adults, but only cedrol played a role in the process of male recognition of females at close range. Therefore, males rely on both visual and olfactory cues to distinguish females during courtship. Visual cues play a major role in attracting males at the beginning of the courtship chase, while olfactory cues play a role in accurately identifying partners at close range.

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When attacked by herbivores, plants emit volatiles to attract parasitoids and predators of herbivores. However, our understanding of the effect of plant volatiles on the subsequent behaviour of conspecific parasitoids when herbivores on plants are parasitized is limited. In this study, rice plants were infested with gravid females of the brown planthopper (BPH) Nilaparvata lugens for 24 hr followed by another 24 hr in which the BPH eggs on plants were permitted to be parasitized by their egg parasitoid, Anagrus nilaparvatae; volatiles from rice plants that underwent such treatment were less attractive to subsequent conspecific parasitoids compared to the volatiles from plants infested with gravid BPH females alone. Chemical analysis revealed that levels of JA and JA‐Ile as well as of four volatile compounds—linalool, MeSA, α‐zingiberene and an unknown compound—from plants infested with BPH and parasitized by wasps were significantly higher than levels of these compounds from BPH‐infested plants. Laboratory and field bioassays revealed that one of the four increased chemicals—α‐zingiberene—reduced the plant's attractiveness to the parasitoid. These results suggest that host plants can fine‐tune their volatiles to help egg parasitoids distinguish host habitats with parasitized hosts from those without.

The pathway mediated by jasmonic acid (JA), biosynthesized via 13‐lipoxygenases (LOX), plays a central role in both plant development and defense. In rice, there are at least fourteen 13‐LOXs. Yet, only two 13‐LOXs have been known to be involved in the biosynthesis of JA and plant defenses in rice. Here we cloned a chloroplast‐localized 13‐LOX gene from rice, OsRCI‐1, whose transcripts were upregulated following infestation by brown planthopper (BPH, Nilaparvata lugens), one of the most important pests in rice. Overexpression of OsRCI‐1 (oeRCI lines) increased levels of BPH‐induced JA, jasmonate‐isoleucine, trypsin protease inhibitors and three volatile compounds, 2‐heptanone, 2‐heptanol and α‐thujene. BPHs showed a decreased colonization, fecundity and mass, and developed slowly on oeRCI plants compared with wild‐type (WT) plants. Moreover, BPH‐infested oeRCI plants were more attractive to the egg parasitoid of BPH, Anagrus nilaparvatae than equally treated WT plants. The decreased attractiveness to BPH and enhanced attractiveness to the parasitoid of oeRCI plants correlated with higher levels of BPH‐induced 2‐heptanone and 2‐heptanol, and 2‐heptanone, respectively. Compared with oeRCI plants, WT plants had higher plant height and 1000‐grain weight. These results indicate that OsRCI‐1 is involved in herbivore‐induced JA bursts and plays a role in plant defense and growth.