Dust in the host galaxies of gamma-ray bursts (GRBs) dims and reddens their afterglow spectra. Knowledge of the nature of this dust is crucial for correcting for extinction, providing clues to the nature of GRB progenitors, and probing the interstellar medium of high-redshift galaxies as well as the nature of cosmic dust when the universe was much younger and galaxies were much less evolved. The dust and extinction properties of GRB host galaxies are still poorly known. Unlike previous work, we derive in this Letter the extinction curves for 10 GRB host galaxies without a priori assumption of any specific extinction types (such as those of the Milky Way or Small/Large Magellanic Clouds). It is found that there appear to exist two different types of extinction curves: one is relatively flat and gray, and the other displays a steeper dependence on inverse wavelength, closely resembling that of the Milky Way but with the 2175 feature removed.

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BackgroundWe intended to investigate the long-term clinical characteristics, responses to therapy and survival in patients with lightchain multiple myeloma (MM).MethodsNinety-six patients were enrolled into the study. There were 42 κ-chain MM patients and 54 λ-chain MM patients. All the patients werestage III in the Durie-Salmonstaging system. Among them, 66 patients received Velcade (bortezomib) treatment and the other 30 did not.ResultsThe main symptoms of these patients included bone pain (77.1%), weakness and fatigue (12.5%), foamy urine (8.3%) and extramedullaryplasmocytomas (33.3%). The overall response rate (ORR) was 95.5% in patients treated with Velcade and 60%in the patients without. The median survival times were 23 months in patients treated with Velcade and 12 months in patients without. The median time of progression-free survival (PFS) was nine months in patients treated with Velcade and five months in patients without. The one-year PFS and two-year PFS were 37% and 25%, 27% and 9% for patients treated with Velcade, or without, respectively. The three-year overall survival (OS) and five-year OS were 33% and 24%, 28% and 9% for patients treated with Velcade, or without, respectively. There was no significance in OS between the two groups (P = 0.335). But there was significant difference in PFS between the two groups (P = 0.036).ConclusionsOur long-term study demonstrated that patients with lightchain myeloma appeared to have more aggressive disease courses and poor outcomes, which could be improved by treatment with Velcade.

bioRxiv preprint 23 impacted many aspects of human society. Here, we analyzed genetic variation of SARS- 24 CoV-2 and its related coronavirus and found the evidence of intergenomic recombination. 25 After correction for mutational bias, analysis of 137 SARS-CoV-2 genomes as of 2/23/2020 26 revealed the excess of low frequency mutations on both synonymous and nonsynonymous 27 sites which is consistent with recent origin of the virus. In contrast to adaptive evolution 28 previously reported for SARS-CoV in its brief epidemic in 2003, our analysis of SARS-CoV-29 2 genomes shows signs of relaxation of selection. The sequence similarity of the spike 30 receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably 31 due to an ancient intergenomic introgression. Therefore, SARS-CoV-2 might have cryptically 32 circulated within humans for years before being recently noticed. Data from the early 33 outbreak and hospital archives are needed to trace its evolutionary path and reveal critical 34 steps required for effective spreading. Two mutations, 84S in orf8 protein and 251V in orf3 35 protein, occurred coincidentally with human intervention. The 84S first appeared on 1/5/2020 36 and reached a plateau around 1/23/2020, the lockdown of Wuhan. 251V emerged on 37 1/21/2020 and rapidly increased its frequency. Thus, the roles of these mutations on 38 infectivity need to be elucidated. Genetic diversity of SARS-CoV-2 collected from China was 39 two time higher than those derived from the rest of the world. In addition, in network analysis, 40 haplotypes collected from Wuhan city were at interior and have more mutational connections, 41 both of which are consistent with the observation that the outbreak of cov-19 was originated 42 from China. SUMMARY 44In contrast to adaptive evolution previously reported for SARS-CoV in its brief 45 epidemic, our analysis of SARS-CoV-2 genomes shows signs of relaxation of selection. The 46 sequence similarity of the spike receptor binding domain between SARS-CoV-2 and a 47 sequence from pangolin is probably due to an ancient intergenomic introgression. Therefore, 48 SARS-CoV-2 might have cryptically circulated within humans for years before being 49 recently noticed. Data from the early outbreak and hospital archives are needed to trace its 50 evolutionary path and reveal critical steps required for effective spreading. Two mutations, 51 84S in orf8 protein and 251V in orf3 protein, occurred coincidentally with human 52 intervention. The 84S first appeared on 1/5/2020 and reached a plateau around 1/23/2020, the 53 lockdown of Wuhan. 251V emerged on 1/21/2020 and rapidly increased its frequency. Thus, 54 the roles of these mutations on infectivity need to be elucidated. 55 56 57 A newly emerging coronavirus was detected in patients during an outbreak of 58 respiratory illnesses starting in mid-December of 2019 in Wuhan, the capital of Hubei 59 Province, China [1 , 2, 3]. Due to the similarity of its symptoms to those induced by the 60 severe acute respiratory syndro...

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