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The South China Sea (SCS) coastlines are particularly vulnerable to tsunamis due to rapid urbanization and dense infrastructures. However, whether the SCS has experienced ocean-wide tsunamis is still under debate. Some geological records from the offshore islands inside the SCS imply a regional tsunami event may have occurred approximately 1000-yr-ago. We address these questions for the first time using forward numerical simulations in the SCS: what source could be responsible for such deposits, how the deposits were formed and at what conditions do the deposits could be preserved? Here, we assume the validity of the tsunami deposit hypothesis and use the forward model COMCOT-SED to investigate if these tsunami deposits can be linked to potential seismogenic tsunami sources inside the SCS, including megathrust earthquakes (Mw8.8–9.2) from the Manila subduction zone (MSZ) and the 1918 Mw7.5 Nan'ao earthquake from the Littoral Fault Zone (LFZ) in the northern continental shelf of the SCS. We also utilize a reported tsunami deposit from Qing'ao Embayment, Nan'ao Island, China, to exemplify the deposit formation process in a typical barrier-low coastal plain system. Quantitative analysis suggests large earthquakes from the MSZ may account for the reported geological deposits. The full-rupture earthquake scenario could best explain the depositions if such extreme case is geophysically and geologically plausible. If not, earthquakes (∼ Mw 9.0) covering the northern (16–23.5°N) or southern portion (14–19°N) of the MSZ could also be suitable candidates. Such great earthquakes can generate large tsunami waves (>7 m) that inundate the Qing'ao Embayment, transporting sediments and leaving tsunami deposits in low-lying areas. Conversely, tsunamis triggered by nearshore earthquakes in the LFZ cannot cause deposition in Qing'ao Embayment. The barrier-low coastal plain system is well-suited for preserving tsunami deposits, which remain unaltered by subsequent tsunami waves. Our findings offer a quantitative reference for paleo-tsunami research in the SCS and enhance global understanding of the tsunami deposition process in barrier-low coastal plain systems. • The full-rupture earthquake (Mw 9.0) from the MSZ best explains the reported plausible tsunami deposits in the South China Sea. • Tsunami waves >7 m generated by MSZ earthquakes could inundate the Qing'ao Embayment anddeposit sediments in low-lying areas. • The barrier-low coastal plain system in Qing'ao Embayment forms favorable conditions to preserve overwash tsunami deposits. [ABSTRACT FROM AUTHOR]

Objectives: The prevention of mother‐to‐child transmission of HIV has been a global success. But little is known about the growth parameters of infants delivered by mothers with HIV or the drug resistance of infants with HIV in China. The study aimed to assess growth parameters and drug resistance in Chinese infants exposed to HIV. Methods: We conducted an 18‐month longitudinal follow‐up study of 3283 infants (3222 without HIV; 61 with HIV) born to mothers with HIV in the Guangxi Zhuang Autonomous Region between January 2015 and December 2021. The weight and length of all participants was recorded. In addition, genetic subtypes and drug resistance analysis were performed for infants with HIV. Results: Compared with infants without HIV, those with HIV had significantly lower weight/length Z‐scores, except at 18 months of age. The length/age Z‐scores of infants with HIV was significantly reduced, except at 1 month of age. The weight/age Z‐scores of infants with HIV were significantly lower at all follow‐up time points. The weight/length Z‐scores of male infants without HIV were significantly lower than for female infants without HIV at all follow‐up time points. Male infants without HIV had lower length/age and weight/age Z‐scores than female infants at the remaining follow‐up points, except at 1 month of age. Of a total of 61 infants with HIV, subtype and drug‐resistance data were obtained from 37 (60.66%) samples. Infants with HIV were dominated by the CRF01_AE genotype and showed a diversity of mutation sites dominated by non‐nucleoside reverse transcriptase inhibitor resistance. Conclusion: Our study demonstrates the growth of infants exposed to HIV in southwest China and provides detailed information on subtype distribution and drug resistance of those with HIV. Nutritional support and drug‐resistance surveillance for infants exposed to HIV need to be strengthened. [ABSTRACT FROM AUTHOR]

In recent years, the occurrence of fowl adenovirus 2 (FAdV-2) has been on the rise in China, posing a significant threat to the poultry industry. This study aimed to investigate the epidemiology, phylogenetic relationship, genomic characteristics, and pathogenicity of FAdV-2. The epidemiological analysis revealed the detection of multiple FAdV serotypes, including FAdV-1, FAdV-2, FAdV-3, FAdV-4, FAdV-8a, FAdV-8b, and FAdV-11 serotypes. Among them, FAdV-2 exhibited the highest proportion, accounting for 21.05% (8/38). The complete genomes of these 8 FAdV-2 strains were sequenced. Genetic evolution analysis indicated that these FAdV-2 strains formed a separate branch within the FAdV-D group, sharing 94.60 to 97.90% nucleotide similarity with the reference FAdV-2 and FAdV-11 strains. Notably, the recombination analysis revealed that 5 out of the 8 FAdV-2 strains, exhibited recombination events between FAdV-2 and FAdV-11. The recombination regions involved Hexon, Fiber, ORF19 genes and 3′ end. Furthermore, pathogenicity experiments demonstrated that recombinant FAdV-2 XX strain is capable of inducing mortality rate of 66.70% and causing more severe hepatitis hydropericardium syndrome (HHS) in 6-wk-old specific-pathogen-free chickens. These findings contribute to our understanding of the prevalence, genomic characteristics, and the pathogenicity of FAdV-2, providing foundations for FAdV-2 vaccine development. [ABSTRACT FROM AUTHOR]

The Lianfeng fault zone is located at the junction of the Daliangshan subblock and the South China block and is the southern boundary of the Daliangshan subblock. It is a very active tectonic area, which is of great significance to understanding its seismogenic environment. However, there are relatively little existing data on its activity and the timing of its latest activity. In the Jinyang-Ningnan segment of the Lianfeng fault zone along the Jinsha River, remote sensing image interpretation, field geologic surveys, high-precision drone measurements, and sample dating indicate that the river terraces T1 (the lowest, 15–40 m above the local river level) and T2 (60–90 m above the local river level) developed in the mid-Holocene and late Pleistocene. This indicates that the Jinsha River basin has been strongly downcutting since the Late Pleistocene. The fault profiles are mainly exposed in the T1 and T2 terraces of the Jinsha River. Based on this information in combination with the fault characteristics of the sedimentary profile and stratigraphic dating, it is believed that the Lianfeng fault zone was active at least along the Jinyang-Ningnan segment, with the latest activity occurring no earlier than the early to mid-Holocene. [ABSTRACT FROM AUTHOR]