Aims. A hard X-ray shortage, implying the cooling of the corona, was observed during bursts of IGR J17473-272, 4U 1636-536, Aql X-1, and GS 1826-238. Apart from these four sources, we investigate here an atoll sample, in which the number of bursts for each source is larger than 5, to explore the possible additional hard X-ray shortage during Rossi X-ray timing explorer (RXTE) era. Methods. According to the source catalog that shows type-I bursts, we analyzed all the available pointing observations of these sources carried out by the RXTE proportional counter array. We grouped and combined the bursts according to their outburst states and searched for the possible hard X-ray shortage while bursting. Results. We found that the island states of KS 1731-260 and 4U 1705-44 show a hard X-ray shortage at significant levels of 4.5 and 4.7σ and a systematic time lag of 0.9 ± 2.1 s and 2.5 ± 2.0 s with respect to the soft X-rays, respectively. While in their banana branches and other sources, we did not find any consistent shortage.

Background Trucks play a vital role in promoting regional freight transportation and economic development, but truck-involved collisions often have more severe consequences and create greater losses for society. Research purpose This study examined the relationships between injury severity and various explanatory factors in truck-involved collisions to identify preventive countermeasures for safety improvement. Data Los Angeles’ collision records from 2010 to 2018 were analyzed. Method A cumulative link mixed model was applied, where the heterogeneities among drivers were highlighted. Result Our findings confirmed that various driving mistakes, such as speeding, improper driving, and drinking alcohol, contributed to severe injuries. Male drivers were more likely to be severely injured, while female occupants were more likely to be severely injured. The use of safety equipment always helped mitigate injury severity. Collisions at night on dark roads with no streetlights and collisions on slippery road surfaces had higher risks of causing severe injuries. In addition, collisions on ramps were more likely to result in severe injuries. Drivers in old trucks were also at a higher risk of suffering from severe injuries. Conclusions Freight companies are encouraged to monitor drivers’ performance using remote cameras. Policy-wise, local agencies should regulate improper driving behavior and safety equipment use for truck drivers. Improving lighting conditions, periodically testing the skid resistance of road surfaces, adjusting speed limits, and applying weigh-in-motion technologies may greatly help mitigate injury severity. Old trucks should be brought in for frequent tests or abandoned after many years of usage.

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Risk Analysis and Crisis Response under the Background of the Belt and Road (RAC-18