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Distributed plates have been proven effective in controlling the vortex shedding and reducing the drag force of a circular cylinder, but more studies on its effect on vortex-induced vibration (VIV) are needed. This paper presents a systematic study of the effect of distributed cross-plates on the suppression of the VIV of a flexible cylinder using wind tunnel experiments. The experiments are performed by changing the length (l), width (w), and number (N) of the cross-plates, the spacing (S) between the adjacent cross-plates, and the aspect ratio (λ) of the flexible cylinder. The flexible cylinder is allowed to vibrate in the transverse direction for a reduced velocity range of 3.0–9.5, corresponding to a Reynolds number of 10,000–49,000. The results show that the optimal configuration of the distributed cross-plates for suppressing VIV is (l / D, w / D, S / D) = (2.0, 0.5, 4), where D is the cylinder diameter. The maximum amplitude decreases monotonically with increasing length and width, respectively. The optimal spacing is independent of λ of the flexible cylinder. For the optimal configuration, the vibration can be fully suppressed in many cases, and the minimum reduction of the maximum amplitude is 14% depending on N and λ, demonstrating a potential application of the distributed cross-plates. [ABSTRACT FROM AUTHOR]

• Serum from breakthrough infections can induce broad neutralization. • Vaccines play a role by reducing viral load and attenuating infection symptoms. • Omicron XBB.1.16 exhibits a high potential for immune escape. To assess the levels of and neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its mutants in serum samples from patients with breakthrough infection. Sixty-four patients with breakthrough infections were recruited for this cross-sectional study. All samples were used to neutralizing antibodies (nAbs) against SARS-CoV-2 and its mutants using a focused reduction neutralization assay. A total of 512 serum samples were obtained from unvaccinated patients who received one dose of vaccine (n = 12), received two doses of vaccine (n = 15), and received three doses of vaccine (n = 37). The geometric mean titer (GMT) of neutralizing antibodies against the Omicron subvariant was significantly lower (GMT 66.8 and 56.1) compared to the original strain, regardless of whether two or three doses of vaccine were administered. This result highlights that sera from breakthrough infections induce broad neutralization, but Omicron XBB.1.16 exhibits high immune evasion potential. [ABSTRACT FROM AUTHOR]

Background. Noroviruses are the most frequent cause of epidemic acute viral gastroenteritis in China. Objectives. The aim of this study was to determine the molecular epidemiological characteristics of norovirus outbreaks and the molecular genetic features of norovirus in Zhejiang Province during 2021. Methods. First, the local Centers for Disease Control and Prevention in the outbreak area conducted on‐site epidemiologic investigations and collected samples from ill patients for initial testing. The general epidemiologic characteristics of the demographic information are presented through descriptive analysis. Positive samples were sent to the Microbiology Laboratory of Zhejiang Provincial Center for Disease Control and Prevention for further verification. The presence of norovirus genogroups I (GI) and II (GII), along with sapovirus, was detected. Subsequently, the specimens positive for norovirus were sequenced for genotyping purposes. Furthermore, the whole genomes of positive samples were sequenced, enabling the characterization of both nucleotide and amino acid differences within the virus. Finally, phylogenetic trees were constructed to further analyze and understand the genetic relationships among the detected viruses. Result. 227 norovirus outbreaks were reported in Zhejiang Province, China, during 2021. Schools were the main setting while January was the peak month for outbreaks. A total of 17 diverse genotypes of norovirus were identified in 2021, and GII.P16‐GII.2 was the most frequent genotype (30.19%). Seven genomes (five GI.P4‐GI.5 and two GII.P16‐GII.2) were obtained. Although GI.P4‐GI.5 is considered to be a rare genotype of norovirus, the prevalence might have been underestimated. Capsid microvariation of GII.2 displayed histo‐blood group antigen binding patterns compared to the GII.2 prototype, although VP1 sequences were considered to have a minimal impact on antigenicity. Conclusion. This study revealed the diversity of norovirus strains' genotypes circulating in Zhejiang Province in 2021. Continued molecular surveillance of noroviruses should be strengthened in our further efforts to the development of vaccines. [ABSTRACT FROM AUTHOR]