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Since 2013, a total of 167 human infections with swine-origin (variant) influenza A viruses of A(H1N1)v, A(H1N2)v, and A(H3N2)v subtypes have been reported in the United States. Analysis of 147 genome sequences revealed that nearly all had S31N substitution, an M2 channel blocker-resistance marker, whereas neuraminidase inhibitor–resistance markers were not found. Two viruses had a polymerase acidic substitution (I38M or E199G) associated with decreased susceptibility to baloxavir, an inhibitor of viral cap-dependent endonuclease (CEN). Using phenotypic assays, we established subtype-specific susceptibility baselines for neuraminidase and CEN inhibitors. When compared with either baseline or CEN-sequence–matched controls, only the I38M substitution decreased baloxavir susceptibility, by 27-fold. Human monoclonal antibodies FI6v3 and CR9114 targeting the hemagglutinin’s stem showed variable (0.03 to >10 µg/mL) neutralizing activity toward variant viruses, even within the same clade. Methodology and interpretation of laboratory data described in this study provide information for risk assessment and decision-making on therapeutic control measures.

With the increasing burden of hypertension in Chinese adults, the detection rate of hypertension among children and adolescents continued to rise, drawing increasing attention to the impact of pubertal timing on blood pressure. In recent years, many scholars have evaluated the association between pubertal development and blood pressure at different stages using various methods of assessing pubertal timing. To understand the correlation between pubertal timing and blood pressure in adolescents, this study reviews the associations between pubertal timing and blood pressure and their underlying mechanisms. The relationship between earlier female pubertal development and the risk of hypertension in adulthood shows positive, negative, and U-shaped correlations, with varying results. Earlier female pubertal development may lead to a higher detection rate of hypertension during adolescence. Most of the studies focus on the correlation between pubertal timing and adult blood pressure, with less research on adolescent blood pressure, indicating a need for further research to reveal underlying patterns.

As a sustainable alternative to using virgin polymer, we propose the use of recycled polymer for the fabrication of passive radiative cooling materials to tackle both the increasing demand for cooling systems and to upcycle plastic waste. Using recycled acrylic sheets as the binder for BaSO4 thorough sol–gel method, a sustained 1.2 °C sub-ambient temperature during daytime and 3 °C sub-ambient temperature during nighttime was achieved under the hot and humid conditions of the tropical climate. The coating achieved 97.7 % solar reflectance and 95 % infrared emittance. Separately, when porosity is introduced to recycled acrylic sheets through a phase inversion method, a near-ambient temperature during noontime and sustained sub-ambient temperature of 2.5 °C during nighttime was achieved (with 96.7 % solar reflectance). Comparable performances are also obtained using recycled polyvinyl chloride (PVC) pipe and expanded polystyrene (EPS) foam.

Plastic bronchitis (PB) constitutes a life-threatening pulmonary disorder, predominantly attributed to Mycoplasma pneumoniae (MP) infection. The pathogenic mechanisms involved remain largely unexplored, leading to the absence of reliable approaches for early diagnosis and clear treatment. Thus, the present investigation aimed to develop an MP-induced mouse model of PB, thereby enhancing our understanding of this complex condition. In the first stage, healthy BALB/c mice were utilized to investigate the optimal methods for establishing PB. This involved the application of nebulization (15–20 min) and intratracheal administration (6–50 μL) with 2-chloroethyl ethyl sulfide (CEES) concentrations ranging from 4.5% to 7.5%. Subsequently, the MP model was induced by administering an MP solution (2 mL/kg/day, 108 CFU/50 μL) via the intranasal route for a duration of five consecutive days. Ultimately, suitable techniques were employed to induce plastic bronchitis in the MP model. Pathological changes in lung tissue were analyzed, and immunohistochemistry was employed to ascertain the expression levels of vascular endothelial growth factor receptor 3 (VEGFR-3) and the PI3K/AKT/mTOR signaling pathway. The administration of 4.5% CEES via a 6 µL trachea was the optimal approach to establishing a PB model. This method primarily induced neutrophilic inflammation and fibrinous exudate. The MP-infected group manifested symptoms indicative of respiratory infection, including erect hair, oral and nasal secretions, and a decrease in body weight. Furthermore, the pathological score of the MP+CEES group surpassed that of the groups treated with MP or CEES independently. Notably, the MP+CEES group demonstrated significant activation of the VEGFR-3 and PI3K/AKT/mTOR signaling pathways, implying a substantial involvement of lymphatic vessel impairment in this pathology. This study successfully established a mouse model of PB induced by MP using a two-step method. Lymphatic vessel impairment is a pivotal element in the pathogenetic mechanisms underlying this disease entity. This accomplishment will aid in further research into treatment methods for patients with PB caused by MP.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into numerous lineages with unique spike mutations and caused multiple epidemics domestically and globally. Although COVID-19 vaccines are available, new variants with the capacity for immune evasion continue to emerge. To understand and characterize the evolution of circulating SARS-CoV-2 variants in the U.S., the Centers for Disease Control and Prevention (CDC) initiated the National SARS-CoV-2 Strain Surveillance (NS3) program and has received thousands of SARS-CoV-2 clinical specimens from across the nation as part of a genotype to phenotype characterization process. Focus reduction neutralization with various antisera was used to antigenically characterize 143 SARS-CoV-2 Delta, Mu and Omicron subvariants from selected clinical specimens received between May 2021 and February 2023, representing a total of 59 unique spike protein sequences. BA.4/5 subvariants BU.1, BQ.1.1, CR.1.1, CQ.2 and BA.4/5 + D420N + K444T; BA.2.75 subvariants BM.4.1.1, BA.2.75.2, CV.1; and recombinant Omicron variants XBF, XBB.1, XBB.1.5 showed the greatest escape from neutralizing antibodies when analyzed against post third-dose original monovalent vaccinee sera. Post fourth-dose bivalent vaccinee sera provided better protection against those subvariants, but substantial reductions in neutralization titers were still observed, especially among BA.4/5 subvariants with both an N-terminal domain (NTD) deletion and receptor binding domain (RBD) substitutions K444M + N460K and recombinant Omicron variants. This analysis demonstrated a framework for long-term systematic genotype to antigenic characterization of circulating and emerging SARS-CoV-2 variants in the U.S., which is critical to assessing their potential impact on the effectiveness of current vaccines and antigen recommendations for future updates.

Emerging SARS-CoV-2 variants raise concerns on immune evasion. Here, the authors evaluate the neutralization efficiency of COVID-19 mRNA vaccinee sera against representative viruses of 13 WHO-designated SARS-CoV-2 variants of concern/interest.

The emergency door on the wing of a civil aircraft has particularity,and its fault is somewhat concealed,so it is particularly important to analyze its safety reasonably.The evaluation and selection principles of the latent failure of the emergency door are defined,and the exposure time of the latent failure is considered in the solution procedure of the failure probability of the bottom event.The fault tree of accidental opening of emergency door in flight is established.The bottom event of“the latch axis movement being not in place caused by tolerance accumulation”,which is generally constructed,is considered as the mechanism movement not being in place caused by the joint action of tolerance accumulation and structural wear.The modeling technology of fault tree bottom event is refined,and its safety is analyzed.The results of reliability analysis before and after fault tree refinement are compared.The results show that the refined fault tree is more in line with the engineering practice,and the reliability analysis result of emergency door is more accurate.

Carrier reuse technology is an important method to reduce the cost of Passive Optical Networks (PON) and multiplexing technology is the main method to improve the transmission capacity of PON. A PON system is designed in this paper. By combing the Subcarrier Multiplexing (SCM) and Wavelength Division Multiplexing (WDM) technology, the transmission capacity of PON is increased significantly. The passive reflection filter is used in the system to realize carrier reuse, which greatly reduces the system cost. In the SCM/WDM-PON system, the carrier reuse is achieved by the reflection filter, which is built in the Optisystem software. Using 3 and 6 GHz radio frequency signals as subcarriers in the SCM system, 8 wavelengths signal with a wavelength interval of 200 GHz ranging from 193.1~194.5 THz are used as optical carriers in WDM, and the data rate of users for uplink and downlink transmission is 1 Gbit/s. The effects of the reflection coefficient, optical carrier power and transmission distance on uplink and downlink data transmission performance are studied. When the reflection coefficient of the reflection filter is 97%, the overall system performance is optimal with the optical carrier power of 5 dBm and the transmission distance less than 27.2 km.

In order to generate high-frequency millimeter-wave, this paper proposes a scheme of generating 16-tupling millimeter wave signal with 4 polarization modulators in parallel, using the different polarities of optical sideband to merely reserve optical carrier and the 8nth-order sidebands. By properly selecting the modulation index, we can get the±8th-order optical sideband signal with carrier suppressed. Finally, after the composite optical signals beaten on the photodetector, the 16-tupling millimeter-wave signal is achieved. The principle of generating 16-tupling millimeter-wave signal is theoretically analyzed. The optical sideband suppression ratio of the obtained±8th-order sideband signal is 61.72 dB, and the radio frequency stray suppression ratio of the 16-tupling millimeter-wave signal is 55.70 dB. The optical sideband suppression ratio and the radio frequency stray suppression ratio obtained from the simulation are 60 dB and 53 dB, respectively. The effects of phase offset and modulation index on sidebands suppression ratio are also analyzed. The experimental results are consistent with the theoretical analysis, which can verify the feasibility of the proposed scheme.

The human OAS1 (hOAS1) gene produces multiple possible isoforms due to alternative splicing events and sequence variation among individuals, some of which affect splicing. The unique C-terminal sequences of the hOAS1 isoforms could differentially affect synthetase activity, protein stability, protein partner interactions and/or cellular localization. Recombinant p41, p42, p44, p46, p48, p49 and p52 hOAS1 isoform proteins expressed in bacteria were each able to synthesize trimer and higher order 2′-5′ linked oligoadenylates in vitro in response to poly(I:C). The p42, p44, p46, p48 and p52 isoform proteins were each able to induce RNase-mediated rRNA cleavage in response to poly(I:C) when overexpressed in HEK293 cells. The expressed levels of the p42 and p46 isoform proteins were higher than those of the other isoforms, suggesting increased stability in mammalian cells. In a yeast two-hybrid screen, Fibrillin1 (FBN1) was identified as a binding partner for hOAS1 p42 isoform, and Supervillin (SVIL) as a binding partner for the p44 isoform. The p44-SVIL interaction was supported by co-immunoprecipitation data from mammalian cells. The data suggest that the unique C-terminal regions of hOAS1 isoforms may mediate the recruitment of different partners, alternative functional capacities and/or different cellular localization.