Nicotiana benthamiana and mulberry, resulting in no visible disease symptoms. However, systemic movement of the virus was only observed in mulberry seedlings, suggesting that it has a host-specific pattern of movement. Our findings provide a valuable reference for further studies on QMV and related viruses, contributing to the understanding of viral evolution and biodiversity in mulberry.In this study, we discovered a new virus named Quanzhou mulberry virus (QMV), which was identified from the leaves of an ancient mulberry tree. This tree is over 1300 years old and is located at Fujian Kaiyuan Temple, a renowned cultural heritage site in China. We obtained the complete genome sequence of QMV using RNA sequencing followed by rapid amplification of complementary DNA ends (RACE). The QMV genome is 9256 nucleotides (nt) long and encodes five open reading frames (ORFs). Its virion was made of icosahedral particles. Phylogenetic analysis suggests that it belongs to the unclassified Riboviria. An infectious clone for QMV was generated and agroinfiltrated into  Morus alba) is a deciduous tree belonging to the genus Morus in the family Moraceae and has been cultivated in China for centuries due to its economic significance [Mulberry  [Diospyros kaki) [Cajanus cajan) [N. benthamiana and mulberry, but systemic movement was only observed in mulberry seedlings. This host-specific movement feature of QMV suggests that it may have evolved to specifically infect and move within mulberry plants, making it a potential candidate for targeted delivery of transgenes or for use as a biological control agent against mulberry pests or diseases. In addition, further research is needed to explore the molecular mechanisms behind QMV’s host-specific movement and to investigate its potential as a tool for genetic modification and disease management in the mulberry industry.Recently, several symptomless viruses have been reported in various crops, including Blueberry latent virus (BBLV) in blueberry (ymbosum) , Persimmos kaki) , and Arhs cajan) . In the s cajan) . TherefoThe present study examined mulberry leaves that were collected from Fujian Kaiyuan temple, Quanzhou, Fujian Province, China , which were asymptomatic at the time of collection. Following their removal, the leaves were immediately placed in liquid nitrogen for rapid freezing and then stored at −80 °C until further analysis.https://www.ncbi.nlm.nih.gov/orffinder/, accessed on 10 January 2023), and conserved domains were searched using the CDD/SPARCLE web tool  provided by NCBI  [The sample underwent transcriptome sequencing and analysis at Majorbio Corporation . A standard non-strand-specific cDNA library was prepared, followed, and subjected to RNA sequencing  on an Illumina HiSeq 2500 platform . Raw data trimming and contig assembly were conducted using Trimmomatic (Version 3.90)  and Trin® RACE 5′/3′ kit .Total RNA was extracted from leaf tissues using the MiniBEST Universal RNA Extraction Kit , and the complete genome of QMV was obtained through rapid amplification of cDNA ends (RACE) technology using the SMARTer® Plus High-Fidelity DNA Polymerase , along with a universal primer mix  and gene-specific primers  for the unknown 5′ and 3′-terminal sequences. The purified 5′ and 3′-terminal products were concatenated with a pESI-T vector , followed by transformation into DH5α competent cells. Positive clones were identified via colony PCR using detection primers  and sequenced at Youkang Corporation . Finally, the full-length genome sequence was assembled using DNAMAN software (version 9.0).The kit-specific primers were used to synthesize cDNAs for amplification of the 5′ and 3′ end sequences. Amplification was performed using Hieff CanaceIn this study, we performed phylogenetic analysis using the ORF1 and ORF2 amino acid sequences from the QMV full-length genomic sequence . These shttps://www.takarabio.com/learning-centers/cloning/primer-design-and-other-tools/, accessed on 15 February 2023). Two fragments covering the full-length genomic RNA of QMV were amplified and inserted into the pCB301 vector  using the seamless cloning technique.To construct a QMV infectious clone, two primer pairs  with homology arms were designed using the Takara primer design website . PCR amplifications were performed with Hieff Canace® Plus High-Fidelity DNA Polymerase  using a reaction mixture containing 25 μL 2×Canace® Plus PCR buffer, 1 μL cDNA, 2 μL forward/reverse primer (10 μM), 1 μL Hieff Canace® Plus High-Fidelity DNA Polymerase (1 U/μL), and 19 μL distilled water. The PCR amplification procedure was as follows: (1) 3 min denaturation at 98 °C; (2) 30 cycles, each consisting of 10 s at 98 °C, 20 s at 65 °C, and 2.5 min at 72 °C; and (3) 5 min final extension at 72 °C. The purified PCR fragments and linearized pCB301 vector were mixed in proportion with 2×MultiF Seamless Assembly Mix , incubated at 50 °C for at least 30 min, and transformed into DH5α competent cells. Positive clones were screened by colony PCR using specific pCB301 vector detection primers  and sequenced commercially.Total RNA was extracted from leaf tissues using the MiniBEST Universal RNA Extraction Kit  and reverse transcribed into cDNA using HifairAgrobacterium tumefaciens strain GV3101 for agroinfiltration. The transformed agrobacteria were infiltrated into the abaxial surface of Nicotiana benthamiana seedling leaves and the cotyledon of mulberry leaves. For N. benthamiana, inoculated leaves were collected at 3 days post-infection (dpi), and systemic leaves (the second and third leaves at the top of inoculated leaves) were collected at 10 dpi. Cotyledon and true leaves were collected from mulberry seedlings at 10 and 20 dpi. The virus accumulation was detected by RT-PCR using QMV-RdRP primers , and the reaction procedure was as follows: (1) 94 °C for 3 min; (2) 30 cycles, each consisting of 94 °C for 30 s, 55 °C for 30 s, and 72 °C for 1 min; and (3) 72 °C for 5 min. The PCR products were analyzed by electrophoresis on a 1.2% (w/v) agarose gel with nucleic acid dye , and the visualization of DNA molecules was obtained using a BIO-RAD instrument .The pCB301-QMV plasmid was introduced into N. benthamiana and mulberry leaves were infected by QMV at 3 and 10 dpi. The infected leaf samples were cut into small pieces measuring 1 × 3 mm and fixed with 2.5% (v/v) glutaraldehyde and 2% (v/v) osmic acid, respectively. After each incubation for 2 h at room temperature, samples were washed three times with 0.1 M phosphate-buffered (PB) buffer.The v/v) for 15 min. Then, samples were dehydrated with 100% (v/v) ethanol twice for 20 min, and with 100% (v/v) acetone all night.After fixation, the plant samples were dehydrated in ethanol at 50%, 70%, 80%, 90%, and 95% (v/v), a mixture of spurr and acetone in the ratio of 3:1 (v/v) for 3 h, and in 100% spurr embedding agent all night. The sections to be cut were placed at the bottom of the tube and then polymerized at 70 °C for 24 h. Thin sections were subsequently cut and observed under a transmission electron microscope  [The dehydrated samples were immersed in a mixture of spurr and acetone in the ratio of 1:1  .We conducted a virome analysis by analyzing the transcriptome sequencing data from old mulberry leaves collected in the Kaiyuan Temple district of Quanzhou, Fujian Province . Through this analysis, we discovered a new virus that infects mulberry trees, which we named Quanzhou mulberry virus (QMV), a potentially unclassified virus. To obtain the complete genome sequence of QMV, we utilized the RACE method. The 5′ and 3′-terminal PCR products were analyzed by electrophoresis on an agarose gel with nucleic acid dye. The visualization of DNA molecules is obtained using a BIO-RAD instrument A,B and sThe QMV genome consists of 9256 nucleotides (nt) and includes five putative open reading frames (ORFs). ORF1, located at positions 3–1377 nt in the full-length genome, is predicted to encode a viral methyltransferase  with a molecular weight of approximately 35.4 kDa. A blastx search of this sequence revealed the first three results to be 92% coverage and 29.93% sequence identity for Tohsystermes virus , 86% coverage and 31.99% sequence identity for Solenopsis invicata virus 17 , and 96% coverage and 29.31% sequence identity for Wuhan insect virus 8  .ORF2, located at position 1288–6993 nt in the full-length genome, is predicted to encode a viral RNA helicase  and an RNA-dependent RNA polymerase 2 domain . The first three results from a blastx search were the following: 47% coverage and 31.31% sequence identity for Fasciogiga virus , 46% coverage and 32.06% sequence identity for Beihai barnacle virus 2 , and 48% coverage and 30.16% sequence identity for Cordoba virus  .The GenBank accession numbers used are as follows: Tohsystermes virus, QQM16332; Solenopsis invicta virus 17, QRK69406; Wuhan insect virus 8, YP_009344994; Fasciogiga virus, DAZ87875; Beihai barnacle virus 2, YP_009333216; and Cordoba virus, AQM55308. NS means no significant similarity sequences were found in the nr database.ORF3 and ORF4 are located at positions 7015–8115 nt and 8113–8480 nt in the genome, respectively. The protein they encode is unknown. ORF5 is located at positions 8706–9104 nt in the genome and is predicted to encode a 133 aa SP24 protein . HoweverAfter conducting a blastx search on the full-length genomic sequence of QMV, it was found that 33.93% of the sequence showed similarity to unclassified viruses and 32.04% similarity to unclassified Riboviria. The first phylogenetic tree is based on the QMV ORF1 sequence and part of representative members, whose sequences were downloaded from the blastx search results. The phylogenetic analysis shows that the virus ORF1 falls in the clade with Daeseongdong virus 1  and Negevirus nona 1 , Megastigmus ssRNA virus , and Hibiscus green spot virus 2  .Additionally, when performing a blastx search on the ORF3, ORF4, and ORF5 sequences, no significant similarity with known proteins in the nr databases was found. Based on these findings, it can be concluded that QMV should be classified as a member of the unclassified Riboviria.w/v) agarose gel with nucleic acid dye , using transcriptome sequencing of mulberry leaves collected in Kaiyuan Temple, Quanzhou, Fujian Province, China. Phylogenetic analysis revealed QMV as an unclassified Riboviria. The complete QMV genome was successfully amplified, and an infectious clone was generated. Agroinoculation assays were used to investigate QMV infectivity in Based on QMV biological properties, developing a QMV vector for expressing foreign genes in mulberry appears feasible. In recent years, several virus vectors have demonstrated successful use in expressing foreign genes for controlling and researching gene function in fruit trees. Previous studies on virus vectors have shown their ability to effectively express foreign proteins. For instance, since citrus leaf blotch virus (CLBV) infections are symptomless in most citrus species, CLBV-based vectors were successfully used to analyze citrus gene function by silencing or overexpressing these genes in citrus trees ,29,30. COryctes rhinoceros, Coleoptera: Scarabaeidae) has been a successful example of classical biocontrol with a virus, resulting in a significant reduction in palm damage in numerous regions throughout the Asia/Pacific area [Previous studies have proposed that weakened strains of plant viruses can be utilized in viral biocontrol techniques to protect plants from more severe strains of the same species . The appfic area . Similarfic area . Given tN. benthamiana plants suggest specific interactions between the virus and its plant hosts, which could be further investigated for important insights into the interactions between QMV and its plant hosts. Overall, this study expands our knowledge of the diversity and evolution of plant viruses and provides valuable tools and insights for future investigations into QMV and related viruses.Transcriptome sequencing and infectious clone technology have been valuable tools for discovering and characterizing novel plant viruses. Further research into the ecology, evolution, and molecular biology of plant viruses will be essential for understanding their impact on plant health and global food security. The differing abilities of QMV to move within mulberry and


Monkeypox, or mpox, is a disease that has recently resurfaced and spread across the globe. Despite the availability of an FDA-approved vaccine (JYNNEOS) and an effective drug (tecovirimat), concerns remain over the possible recurrence of a viral pandemic. Like any other virus, mpox virus must overcome the immune system to replicate. Viruses have evolved various strategies to overcome both innate and adaptive immunity. Poxviruses possess an unusual nuclease, poxin, which cleaves 2'-3'-cGAMP, a cyclic dinucleotide, which is an important second messenger in the cGAS-STING signaling pathway. Here, we present the crystal structure of mpox poxin. The structure reveals a conserved, predominantly β-sheet fold and highlights the high conservation of the cGAMP binding site and of the catalytic residues His17, Tyr138, and Lys142. This research suggests that poxin inhibitors could be effective against multiple poxviruses.The online version contains supplementary material available at 10.1007/s00705-023-05824-4. Mpox, previously known as monkeypox, is a disease that has recently re-emerged . It was Poxviridae) already in the late 1970s [Mpox virus (MPXV), like any other virus, must overcome the immune system to successfully replicate . Innate te 1970s . Furtherte 1970s . Howeverte 1970s .Interestingly, poxviruses possess a nuclease that is rather unusual and was named after them – poxin , 14. ItsIn this study, we successfully determined the crystal structure of the poxin protein from mpox virus. We have identified a conserved hotspot that serves as the binding site for cGAMP and is a potential target for inhibitor design. Novel strategies based on inhibition of poxin, can be developed to combat mpox virus infections.1 spacegroup and diffracted to 1.7Å resolution. The structure was solved by molecular replacement using the vaccinia virus (VACV) poxin as a search model [work = 21.36%, Rfree = 22.84%) and good geometry  and a C-terminal domain (CTD) Fig. , similarHowever, to form an active enzyme, poxin needs to form a dimer , 15, whiThe mpox poxin shares 91% identity with the VACV poxin . We analyzed the conservation of the catalytic residues. The cGAMP binding site is localized at the dimer interface, and His17 from one monomer and Tyr138 with Lys142 from the other were identified as the residues responsible for poxin-catalyzed cleavage of cGAMP, as in the case of the VACV poxin [Poxviridae. However, the effectiveness of using poxin as an antiviral target requires the development of potent inhibitors to confirm its potential. Tecovirimat, the only FDA-approved drug against mpox, is an inhibitor of the envelope protein p37 [These findings indicate that poxin is a promising target for the development of drugs that can effectively combat multiple members of the family tein p37 , 20, 21.tein p37 , 22–25, tein p37 . Interestein p37 , 28. Thetein p37 –32. Sometein p37 . We specSupplementary file1 (PDF 841 KB)Below is the link to the electronic supplementary material.


The role of vitamin E in blood pressure (BP) has been controversial. We aimed to investigate the relationship between gamma-tocopherol serum concentration (GTSC) and BPData from 15,687 US adults from the National Health and Nutrition Examination Survey (NHANES) were analyzed. The correlations of GTSC with systolic BP (SBP), diastolic BP (DBP), and prevalence of hypertension were investigated by multivariate logistic regression models, generalized summation models, and fitted smoothing curves. Subgroup analyses were performed to investigate possible effect modifiers between them.β 1.28, 95% CI 0.71–1.84) and 1.15 mmHg , respectively, both P for trend < 0.001; the prevalence of hypertension increased by 12% , P for trend 0.008. In subgroup analysis, in drinkers, with each natural log increase in GTSC, SBP, and DBP increased by 1.77 mmHg  and 1.37 mmHg , respectively, whereas they were not correlated in non-drinkers.With each natural log increase in GTSC, SBP, and DBP increased by 1.28 mmHg (GTSC was linearly and positively associated with SBP, DBP, and the prevalence of hypertension, and alcohol consumption may modify the relationship of GTSC with SBP and DBP. In the Many factors have been shown to be associated with BP increase, such as socio-demographic factors like gender, age, ethnicity, and environmental and behavioral factors. There are also many changeable exposure elements such as a high sodium diet, low potassium diet, obesity, and a sedentary lifestyle that could increase BP . In addiα, β, γ, and δ) and has two main dietary forms in the body, α-tocopherol (ATC) and γ-tocopherol (GTC), of which the most studied is ATC, because ATC is most bioactive and abundant in the blood, and vitamin E deficiency can be corrected by taking this supplement  database of 4 cycles with GTSC data to investigate the correlation between GTSC and BP, and possible modifiers of this relationship.2.2.1.https://www.cdc.gov/nchs/nhanes/index.htm.The data used in this study were all from four cycles in the NHANES database. The NHANES is a continuous representative survey of the U.S. national population that provides a wealth of data on the nutrition and health of adults and children in the U.S. using a complex, multi-stage, probability sampling design. The study was approved by the Ethics Review Committee of the National Center for Health Statistics and with the written consent of each participant. More information can be found at n = 23032) in the NHANES  study. Exclusion criteria are as follows: participants with cancer (n = 2000), patients with missing GTSC data (n = 2494), and participants with missing BP data or hypertension history (n = 2851). Finally, 15,687 participants were included in the statistical analysis  in the data analysis. The outcome variables were SBP, DBP, and the prevalence of hypertension. The SBP and DBP were defined respectively as the average of the SBP and DBP measured at three different times. Hypertension was defined as a self-reported diagnosis of hypertension, or SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg, or the use of antihypertensive medication.2.3.2), and waist (cm)), laboratory data (Albumin (g/L), blood urea nitrogen , uric acid , serum creatinine , estimated glomerular filtration rate , fasting blood glucose , glycated haemoglobin A1c , total cholesterol , triglycerides , high-density lipoprotein cholesterol ), and questionnaire data , coronary artery disease (CAD), smoking, and drinking). Diabetes was defined as a self-reported diagnosis of diabetes or having an HbA1c level ≥ 6.5%, or FPG ≥ 7 mmol/L. HF and CAD were defined as the self-reported diagnosis of HF and CAD, respectively.In our study, covariates included demographic data , examination data (weight (kg), height (cm), body mass index , CAD (yes vs. no), HF (yes vs. no), diabetes (yes vs. no), smoking status (yes vs. no), drinking status (yes vs. no), and eGFR (<60 vs. ≥60 ml/min/1.73 m2).Described continuous data by mean ± standard deviations (SDs) or median  and categorical data by number (%), respectively. Differences between the tertiles of Ln GTSC groups were compared using one-way ANOVA for continuous variables and the chi-square test for categorical variables. In multivariate logistic regression models, covariates were proven traditional or suspected risk factors for hypertension, or the Ln GTSC estimates for SBP, DBP, and hypertension changed by more than 10% . We invehttp://www.R-project.org) and EmpowerStats (http://www.empowerstats.com), with a P value <0.05 considered statistically significant.All analyses were conducted with package R  and a 1.15 mmHg increase in DBP , and a 12% increase in the prevalence of hypertension . We grouped GTSC in tertile groups and used the T1 group as the reference group to further evaluate the relationship between GTSC and BP values and the prevalence of hypertension. Compared with the T1 reference group, SBP increased by 0.71 mmHg  and 1.39 mmHg  in the T2 and T3 groups, respectively, P for trend <0.001; DBP increased by 0.53 mmHg  and 1.39 mmHg , respectively, P for trend <0.001; and the relative risk of hypertension incidence increased by 8%  and 17% , P for trend 0.008. In summary, SBP, DBP, and the prevalence of hypertension were all linearly and positively correlated with GTSC. The above findings are consistent with the results of the smoothed curve fitting  and an increase in diastolic BP of 1.37 mmHg . There was no statistically significant relationship between GTSC and BP (either diastolic or systolic) in individuals who did not consume alcohol. There may be an interaction between GTSC and alcohol consumption in terms of BP , but not in terms of hypertension incidence (P for interaction = 0.28)  . In indi = 0.28) .4.In this large sample cross-sectional study, we found that GTSC was positively associated with SBP, DBP, and the prevalence of hypertension, and this relationship remained significant after adjustment for confounders. Furthermore, we noted that alcohol consumption modifies the relationship of GTSC with SBP and DBP, but not the relationship with the incidence of hypertension.p < 0.05) (α-tocopherol group (500 mg/day for 6 weeks) increased SBP by 7.0 mmHg  and DBP by 5.3 mmHg ; the mixed tocopherol group  increased SBP by 6.8 mmHg  and DBP by 3.6 mmHg . Moreover, the prospective cohort study by Lai et al. including 684 pregnant women, and the cross-sectional study by Francis et al. both concluded that vitamin E (in either form) was not significantly associated with BP  and DBP (−12.5% in the vitamin E versus −6.2% in the placebo group) ( < 0.05) . Althoug < 0.05) , 22, 23. with BP , 25. A r with BP . The conBased on previous studies, the present study is the first to individually investigate the association of GTSC with BP using cross-sectional data from a large sample, adding more evidence to the field. Our study has several important findings. First, our study found that GTSC was linearly and positively correlated with SBP, DBP, and the prevalence of hypertension, with a trend toward higher BP and hypertension prevalence with higher GTC concentrations. It is not clear the specific mechanism by which GTSC increases SBP, DBP, and the prevalence of hypertension, but the following mechanisms might explain it. Firstly, GTC has a dual role in oxidative stress. GTC is known to have antioxidant and anti-inflammatory effects, but some studies indicated that excess GTC could promote the production of nitric oxide, an inflammatory mediator through its oxidation products, leading to an enhancement of cellular immune response and an increase of lipid peroxidation . StudiesSecond, we noted that alcohol consumption could modify the relationship of GTSC with both SBP and DBP. In participants who consumed alcohol, a potentiation of the GTC-driven increase in SBP and DBP was observed, but not in non-drinking participants. Numerous studies have demonstrated that alcohol consumption is positively associated with BP increase, even in small amounts –34. The Although our study is based on nationally representative U.S. general population data and has a large sample size that minimizes bias and has good extrapolation, we must also acknowledge several important limitations of this study. First, this study was a retrospective cross-sectional design, and thus no causal inferences could be made about the association of GTSC with SBP, DBP, and the prevalence of hypertension, which is an inherent drawback of all cross-sectional designs. Second, although we adjusted for numerous confounding factors, we still cannot exclude the interference of unknown confounders  on the study results. In this study, only a single blood test was performed to assess the status of GTC, and repeat sampling may be required to overcome the daily variability of individuals, but this process would become very complex and expensive. Fourth, our study was limited to adults in the United States, so generalization to other countries or age groups requires caution.5.In summary, this study investigated the relationship between GTSC and SBP, DBP, and the prevalence of hypertension in the general U.S. population and found that GTSC was linearly and positively associated with SBP, DBP, and the prevalence of hypertension, and found that this correlation of GTSC with SBP and DBP was more significant in those who consumed alcohol.


Respiratory pathogens transmit primarily through particles such as droplets and aerosols. Although often overlooked, the resuspension of settled droplets is also a key facilitator of disease transmission. In this review, we discuss the three main mechanisms of aerosol generation: direct generation such as coughing and sneezing, indirect generation such as medical procedures, and resuspension of settled droplets and aerosols. The size of particles and environmental factors influence their airborne lifetime and ability to cause infection. Specifically, humidity and temperature are key factors controlling the evaporation of suspended droplets, consequently affecting the duration in which particles remain airborne. We also suggest material‐based approaches for effective prevention of disease transmission. These approaches include electrostatically charged virucidal agents and surface coatings, which have been shown to be highly effective in deactivating and reducing resuspension of pathogen‐laden aerosols. Virus dissemination through droplets or aerosols is a predominant transmission mode of respiratory infections. This review summarizes direct and indirect mechanisms of aerosol generation with an emphasis on infection risks presented by the resuspension of settled droplets. Material‐based approaches, including nanotechnology, to contain bioaerosol‐mediated virus transmission are highlighted in this review. The World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) classify particles with an aerodynamic diameter greater than 5 µm as droplets, while particles less than or equal to 5 µm are termed aerosols or droplet nuclei. As shown in Figure Bacillus anthracis spores was promptly removed after it was opened. However, reports later showed that airborne anthrax was detected in the suite even after 25 days. This was explained by the resuspension of spores that had settled onto surfaces during the initial incident. A greater understanding of bioaerosol resuspension is therefore critical to assess the transmissibility of pathogens. It can provide critical insights into the prevalence and dominance of certain viruses, such as the Delta and Omicron variants of SARS‐CoV‐2, which have more positively charged spike proteins that can lead to longer survival time in aerosols. Notably, positive charge is speculated to increase the interaction of these variants with the negatively charged glycoproteins of mucin found in the droplets. Mucin can therefore form a thin, cross‐linked network that encapsulates and protects the virus in aerosol, leading to longer survival times and posing a greater risk for resuspension.Respiratory infections are one of the most common diseases globally, owing to the ease of transmission through respiratory droplets and aerosols . The ability of bioaerosols to travel long distances and linger in air for a long duration enables dissemination of disease, causing outbreaks such as the COVID‐19 pandemic. Viruses embedded in mucus and saliva are expelled while talking, breathing, coughing, and sneezing. A large number of evidence‐based studies during the COVID‐19 pandemic have demonstrated the transmission of SARS‐CoV‐2 via bioaerosols.1, 2In this review, we discuss different mechanisms of bioaerosol generation with an emphasis on sources of bioaerosol, critical factors that impact their trajectories and transmissibility, and the associated epidemiological risk. Finally, we discuss countermeasures to prevent viral infections via bioaerosol. In particular, we discuss virucidal materials which can be grafted onto different substrates, painted onto surfaces, or applied as a coating to personal protective equipment (PPE), such as medical masks. Given the risk posed by bioaerosol resuspension, measures and materials that can reduce the viability of deposited pathogens could be instrumental in preventing the further spread of respiratory infections. The scope of this review also underlines the significance of bioaerosol resuspension, which is often overlooked as a mode of transmission. We envision that this review will reignite material scientists to develop broad‐spectrum antiviral technologies to combat future outbreaks.2 Coughing and sneezing generate 3000 droplet nuclei and 40,000 droplets, respectively, but coughing expels the highest concentration of droplet nuclei smaller than 1 µm. The number of viral particles found in a droplet can range from 102 to 1011 copies/mL. Theoretically, viral load in the droplets depends on the cube of droplet diameter; however, some studies suggest that smaller droplets may be virus‐enriched. The widely used assumption is that the pathogenic particle distribution in a droplet follows a Poisson distribution. Using a Monte‐Carlo simulation, Wang et al. estimated that a person with a viral load of 2.35 × 109 copies/mL could generate 1.23 × 105 copies of airborne virus by a single cough. The viral load required to trigger an infection depends upon the type of virus. Alford et al. conducted a study to determine the minimum infectious aerosol dose of influenza A2/Bethesda/10/63 in 23 volunteers aged between 21 and 40 years. Volunteers were subject to inhalation of 10 L of aerosolized virus suspensions by face mask. Subjects free of serum neutralizing antibodies were infected by a dose of approximately three tissue culture infectious dose 50 (TCID50), which enumerates 1.95 × 103 viral copies based on subsequent studies estimating 300–650 copies of human influenza viruses in 1 TCID50. A separate survey by Memoli et al. sought to determine the dose of influenza A(H1N1)pdm09 needed to induce mild to moderate infection in 46 healthy volunteers following intranasal exposure. In this study, an amount of 107 TCID50 induced influenza infection in 69% of participants. More recently, there has been an interest in establishing the relationship between viral load and infectivity in SARS‐CoV‐2. A mathematical model by Goyal et al. estimates infectious dose 50 (ID50) of SARS‐CoV‐2 to be 107 viral RNA copies.Pathogen‐laden bioaerosols are generated directly from infected individuals during expiratory activities such as breathing, talking, sneezing, and coughing. These activities generate respiratory droplets varying in both size and viral load. Prior research suggests regular nasal breathing and exhalation discharge submicron and larger droplets.7 Coug In contrast, large droplets (greater than 100 µm) settle down rapidly, contaminating the zone around the host. The relationship between droplet size, duration of suspension in air, and trajectory is shown in Figure  At a height of 1.5 m, larger droplets travel no farther than 1 m before settling down. The terminal velocity of respiratory droplets also affects the horizontal distance they can travel. In contrast to large droplets, the low terminal velocity of small droplets lesser than 5 µm allows them to be suspended in air for more extended periods in conjunction with air currents. Therefore, airflow can facilitate small droplets to reach high altitudes, such as ventilation systems, thereby increasing the incidence of airborne transmission. A recent report validated this by showing the existence of SARS‐CoV‐2 droplets from the ventilation systems in hospital rooms of infected patients.Besides viral load, horizontal distance traveled and time of flight are important factors in determining the transmissibility of aerosols. Studies have revealed that droplets expelled from breathing and coughing can travel distances up to 3–6 feet with speeds less than 10 m/s, while droplets generated from sneezing can propagate 20 feet or more at 50 m/s.18 In  This is further exemplified in another study where the size reduction of a droplet from 50 µm to 10 µm experiences a decrease in terminal velocity from 6.8 cm/s to 0.35 cm/s. Apart from temperature, the evaporation rate is also determined by the differential vapor pressure between the droplet surface and the surrounding air. The magnitude of droplet size reduction during evaporation depends on the nonvolatile solute composition, typically electrolytes, deoxyribonucleic acid, sugar molecules, enzymes, and fragments of desiccated epithelial and white blood cells. The weight percentage of these non‐volatile substances in respiratory fluids ranges from 1% to 5%. Upon exposure to low relative humidity, aerosols composed of salt and organic material encounter liquid–liquid phase partition, resulting in a core–shell assembly. Hence, the amount of droplet evaporation and the concentration of the viral particles in the aerosol are influenced by humidity, as depicted in Table Evaporation also impacts the travel distance and transmission of virus‐laden respiratory droplets. A recent study demonstrated that droplets in the range of 12–21 µm, generated during a loud speech, evaporated to produce droplet nuclei or aerosols (1 µm) within 15 min in an indoor setting. The decrease in size of evaporated droplets is accompanied by a slow terminal velocity and they remain airborne for longer durations.23 Thi In one study, an enveloped virus ϕ6 was uniformly distributed in a desiccated droplet after rapid evaporation at low relative humidity. Viability experiments revealed that the high relative humidity favored adenovirus and rhinovirus stability in aerosols, whereas respiratory syncytial virus (RSV) exhibited dual‐mode stability at 20% and 40% to 60% RH. Dissemination of influenza virus under different RHs and ambient temperatures was studied in a guinea pig model. Higher transmission was observed at 5°C but reduced significantly at 30°C. High humidity (80% RH) was noticeably unsuitable for the transmission of influenza virus, although arid conditions of 20% and 35% RH were perceived as favorable. A few studies have also explored the critical role of absolute humidity in the survival of influenza virus and its transmission efficiency. Low absolute humidity levels during winter strengthen the virus survival and transmission. SARS‐CoV‐2 can survive for several days at moderately low temperatures (less than 20°C) and low absolute humidity. One mathematical study modeled the settling time, transport, and dehydration of SARS‐CoV‐2 containing droplets generated by cough under various RH and air velocities. Results showed that droplet size expanded due to the hygroscopic effect at high relative humidity (>80%) and enhanced droplets' deposition on the ground, whereas respiratory droplets evaporated at 40% RH to form droplet nuclei and persisted in the air. In another study, droplet lifetime was evaluated at different temperature and relative humidity conditions, and an exponential surge in droplet lifetime was observed at 30°C and 55.7% RH. Ultraviolet (UV) light exposure is also known to have a detrimental effect on virus viability, primarily mediated through damage to the viral genome, as described in Table Multiple reports have substantiated the influence of humidity and temperature on droplet lifetime and pathogen stability.29 In 3 These procedures include bronchoscopy, non‐invasive ventilation (NIV), cardiopulmonary resuscitation, manual ventilation, and autopsy. Procedures such as NIV are categorized as AGP as they result in aerosolization of patient expirations due to high velocity gas flows. A study by Lavoie et al. investigated aerosol generation during bronchoscopy and showed a significant increase in aerosol production during the procedure compared to an empty room. However, risk of disease transmission from these AGPs is not well studied. A retrospective study on the nosocomial transmission risk factors of SARS showed that health workers caring for patients treated with NIV had two times increased risk of infection compared to medical staff who had no interaction with NIV‐treated patients. Despite this, the role of AGP is unclear; as the exact transmission route was not determined, the increased infection risk could instead be attributed to close contact with SARS patients. Given the infectious nature of bioaerosols generated from ill patients, there is an understandable concern among physicians and other healthcare workers performing AGPs. Further study into their transmission potential is warranted to ensure that appropriate personal protective equipment is used for these procedures.Primary bioaerosols can also be generated indirectly during medical procedures termed as aerosol‐generating procedures (AGPs).41 The It is also important to note that the aerosols produced by toilet flushing are within the respirable size range (<5 µm). In one study, a toilet bowl was seeded with Serratia marcescens and Escherichia coli to mimic bacterial shedding in stool. A significant number of airborne bacteria were detected after subsequent flushing. Likewise, norovirus persists in the air after toilet flushing and can be a secondary source of infection in closed environments. In another instance, virus particles were detected on floor surfaces from toilet stalls used by patients positive for SARS‐CoV‐2. These studies indicate that indirectly generated bioaerosols remain viable and can disperse in the air for up to 12 h, eventually settling on bathroom surfaces such as walls, floor, flush handle, sink, and cabinet. This underlines the importance of decontamination strategies in hospitals, houses, and other public areas to eradicate secondary sources of infection.Other indirect events of bioaerosol generation include toilet flushing. Toilet plumes have been studied previously in disseminating infectious diseases. The high speed of water flow from the tank creates a centripetal force that expels aerosols from the surface of the bowl, posing infection risks.43 It 4 A study conducted to evaluate the stability of SARS‐CoV‐2 on different surfaces showed that SARS‐CoV‐2 was stable in aerosols for at least 3 h and remained viable on surfaces such as plastic and stainless steel for up to 3 days, thereby posing a high probability for the presence of infectious resuspended droplets.Respiratory droplets settled on surfaces have a propensity to detach and resuspend in air through various mechanisms, as shown in Figure 47 A s The first phase involves the detachment of bioaerosol from the substrate, induced by hydrodynamic lift and vibrational forces leading to inceptive motions such as sliding, rolling, and liftoff. Several experiments reveal the dominance of rolling motion as the primary mechanism of particle detachment. The second phase involves resuspension of particles into bulk air streams. Not all dissociated particles become aerosolized; some detached particles transiently settle down due to the opposing gravitational force. In addition to gravitational force, van der Waals interactions, capillary forces, and electrostatic forces counteract resuspension forces to prevent detachment and secondary aerosolization of droplet particles.Resuspension of a settled droplet occurs through a two‐phase process.49 The4.1 Stemming from the 2001 anthrax attacks, numerous studies have investigated the resuspension of B. anthracis spores. In one instance, wiped samples and surface dust were collected to quantify viable resuspended spores under simulated office conditions for 25 days after the initial outbreak. A remarkable increase was observed in the resuspension by events such as active foot trafficking, mail sorting, and moving of trash boxes. An airborne concentration of 100–11000 CFUs m–3 of B anthrax spores within the respirable range of 0.95–3.5 µm was identified. In another study, bioaerosol resuspension was assessed from personnel activity while maintaining a contaminated aerosol sampler. Air samples and swabs from the technician's clothing were investigated, and a significant concentration of 73 CFU/Lair was detected from the air and clothing. Another report revealed the resuspension of spores from mechanical sorting of contaminated envelopes, which led to the infection of employees. These studies demonstrate the substantial risk of resuspended B. anthracis spores by human activity. Resuspension of respiratory droplets also disseminated influenza virus by air turbulences produced during walking. In a previous report, the magnitude of air turbulence was measured in eddy diffusion coefficients. The eddy diffusion coefficients, determined experimentally, were applied to a simulated atmospheric transport model to estimate the concentration of resuspended influenza virus. Eddy diffusion coefficients were highest at 1 m from the floor. Therefore, around 40% of resuspended virus‐laden droplets were highly dispersed at the same height. Moreover, the study interpreted the possibility of different exposure levels of individuals to resuspended aerosols based on body height. People with a height of less than 1 m were more prone to exposure to resuspended viruses. In general, the influenza virus has superior stability and remains viable in outdoor or indoor environments for hours to days. Therefore, resuspension of settled influenza virus droplets could be a potential secondary disease transmission mode. In addition, the resuspension of norovirus has also been recognized as one of the transmission modes of gastrointestinal illness. For example, one study investigated the determinant factors of a norovirus outbreak in a concert hall. Here, the resuspension of contaminated droplets by air vortices generated from walking across the contaminated zone was speculated to be the primary transmission mode of norovirus.A critical contributing factor to bioaerosol resuspension is sporadic air perturbances from human activities in indoor and outdoor settings Figure .51]51[5 An increased concentration of airborne SARS‐CoV‐2 was observed in staff areas due to resuspension of virus‐laden droplets. It was hypothesized that airflow generated from personnel movements propagated aerosols from patient rooms to staff areas. The highest airborne concentrations, 18 to 42 copies m–3 of SARS‐CoV‐2 viral RNA, were detected in the protective apparel changing rooms. This was attributed to the resuspension of settled virus‐laden aerosols by vibrational forces induced by doffing of protective equipment by medical staff who had been in close proximity to infected patients  tested positive for viral RNA. Scientists attributed these observations to the resuspension of aerosols by air vortices generated from a door opening as shown in Figure Resuspension of SARS‐CoV‐2 containing droplets due to human activity has also been investigated. A field report from Wuhan, China, quantified aerosol samples from medical staff areas in hospitals.56 An s Figure . Similar Surface roughness also determines the initial rolling of droplets during the first phase of resuspension. In a study, the resuspension of droplets was compared between different substrate surfaces such as glass, hardwood, and ceramic. Particles deposited on glass, and ceramic surfaces experienced a longer rolling motion and required high energy to resuspend from the smooth surfaces in contrast to hardwood.Surface roughness is a critical factor that influences the adhesion of a droplet to the substrate. Smooth surfaces increase the contact area at the droplet–surface interface and lead to strong adhesion. Conversely, droplets settled on rougher surfaces experience weak adhesion forces, allowing them to resuspend more effortlessly.59 Sur However, these coatings can promote resuspension of settled droplets due to tiny air currents or mechanical forces generated by activities such as vacuum cleaning, as shown in Figure Surface coatings can modulate substrate properties such as surface energy and wettability and therefore determine the fate of resuspension. Floor carpets are usually coated with fluorocarbon and linoleum to reduce the surface energy and the wettability of the fibers to facilitate easy removal of dust or dirt.60 How4.2 However, the presence of water can still enhance virus spread indirectly by disrupting air filtration. For example, Kim et al. showed that the time required to remove particulate matter (PM) from a chamber increased noticeably in wet semi‐HEPA filters compared to dry filters. Additionally, dust‐borne transmission has been established as an important route for disseminating avian viruses. Although avian influenza outbreaks have been primarily associated with poultry and bird migrations, outbreaks in Japan, South Korea, and Taiwan have coincided with Asian dust storm (ADS) seasons. Chen et al. quantified airborne virus concentration during ADS and non‐ADS days and found 20‐ to 30‐fold higher virus concentration on ADS days compared to background days. This result further implicates dust as an important vector for long‐distance transmission. Moreover, a group of scientists studied the epidemiological factors contributing to the outbreak of B. anthracis and concluded that windborne resuspension of anthrax pathogen was one of the supplementary causes of the outbreak. In an indoor environment, heating, ventilation, and air conditioning (HVAC) systems are usually considered to improve air quality by diluting, filtering, and removing dust and contaminants. However, recent studies suggest that HVAC systems may enable the infiltration, entrapment, and distribution of respiratory pathogens  filters are used to ensure higher air quality. HEPA filters are regulated by US government standards to be able to remove 99.97% of 0.3 µm particles. A NASA study shows that typical HEPA filters are nearly 100% efficient at capturing larger and smaller particles than 0.3 µm. However, the capture efficiency declines to 99.97% at the 0.3 µm mark. This is known as the most penetrating particle size (MPPS). The particle sizes of the coronavirus family, which includes SARS‐CoV‐2 and MERS‐Cov, range from 0.06 to 0.2 µm, which is well under the MPPS for commercial HEPA filters. However, viral particles may adhere to aggregates and dust particles to give a final size of 0.3 µm. Therefore, these particles still have a 0.03% probability of escaping HEPA filters. The penetration of viral particles through HEPA filters has been demonstrated by Heimbuch et al. in a laboratory setting. Thus, indoor spaces such as airplanes and hospitals are susceptible to virus entry and redistribution even when equipped with HEPA filters, and appropriate decontamination strategies must be adopted to reduce transmission risk.Installation of portable air cleaners and equipping furnace and HVAC systems with filters have been suggested as strategies to remove dust and contaminants from indoor air.68 Fil5 This section provides a high‐level overview of the material perspective on current applications of antiviral agents in PPE, medical equipment, consumer products, and public settings. A broad array of natural and synthetic materials, including polymer and metals, that can be utilized as surface coatings to deactivate and prevent resuspension of viable virus‐laden droplets is discussed.Both primary and resuspended aerosols serve as sources of respiratory infection and necessitate effective approaches to prevent further transmission. A myriad of innovative materials with antiviral properties have been studied recently, driven in part by the COVID‐19 pandemic.72 Thi5.1 and polyamides, post‐modified with alkyl groups to form the quaternary center, and homo‐ or co‐polymerized diallyl quaternary amines. Natural biopolymer dextran sulfate and other polysaccharide‐based or non‐polysaccharide‐based sulfated polymers such as carrageenan and alginic acid have long been known for their antiviral property. The polysulfates bind to the positively charged gp120 envelope protein of HIV to intercept heparan sulfate, the host cell target. The wide application of anionic polysulfates extends to other enveloped and non‐enveloped viruses, including influenza and rhinoviruses, suggesting that they may bind to viral glycoproteins. In particular, carrageenan and alginic acid have shown applications as virucidal coatings in other settings, including dip‐coating for fresh food to prevent viral and bacterial entry. Anionic, nonionic, cationic, and zwitterionic surfactants have exhibited antiviral activity. This is attributed to the interaction between the surfactants’ hydrophobic tails and the phospholipid bilayers of the viral envelopes, leading to disintegration and viral deactivation. This mechanism is especially important in enveloped viruses, including influenza and SARS‐CoV‐2. Rhamnolipids, sophorolipids, and similar biosurfactants are of particular interest owing to their biodegradability and low ecotoxicity. Recently, two rhamnolipid products, 222A and 222B, were investigated and demonstrated excellent viral deactivation. Although surfactants are primarily used to disinfect surfaces, they may also be embedded in fibers to deactivate viruses that come in contact.Electrostatically charged materials with virucidal properties have been commonly applied as a surface coating. Both cationic and anionic materials appear to be effective, albeit with distinct mechanisms. Cationic materials usually act via viral capsid destruction, while anionic materials bind to the virus and neutralize their spike proteins. Synthetic polymer‐based antiviral materials often consist of N‐alkylated quaternary amine structures with a positive charge to electrostatically attract viruses and disrupt the protein capsid. This category of virucidal polymers involves derivatives of polyethyleneimine and other existing polymers containing nitrogen, such as polyurethanes73 and Cellulose non‐woven layers were modified by Catel‐Ferreira et al. through conjugation of catechin polyphenol to impart antiviral properties in wipes and mask filters. Compared to the control, the use of chemically modified wipes decreased the bacteriophage population by 2‐log against a T4D bacteriophage suspension. Additionally, virus filtration experiments were performed to test the viability of catechin polyphenol modified filter‐based applications against an aerial suspension of T4D bacteriophage virus. The study results highlighted antiviral properties of polyphenols and potential applications of their presence on polymeric materials.Surfaces of polymeric materials have also been shown to achieve antiviral properties through the use of polyphenols. Polyphenols have previously been shown to display antimicrobial activity against human pathogens through direct action against bacteria and suppression of microbial virulence factors.83 CelNanomaterials have also been explored as virucidal agents, as summarized in Table  Metal nanoparticles interfere with viruses’ ability to locate and bind to host cells either by modification or competitive inhibition of specific recognition sites on the capsid. These approaches either utilize the metal's inherent properties or act through grafted pendant functionality. Unmodified gold naturally cleaves disulfide bonds in hemagglutinin, an influenza surface protein, preventing the virus attachment to host cells. In particular, silver nanoparticles have been extensively used and reviewed elsewhere and can both inactivate and capture viruses. Similar disulfide interactions occur between silver nanoparticles and dengue virus. Although metal nanoparticles do not exhibit specific interaction with viruses, grafting functional groups can be used to impart specificity. For instance, mercaptoethanesulfonate is widely used as a mimic for heparan sulfate and has been employed against the herpes simplex virus, coronaviruses, and arteriviruses. Although pristine gold cleaves disulfide bonds, gold nanoparticles were reported to attenuate the antiviral activity against influenza. However, grafting of sialic acid to gold nanoparticles impedes the binding of virus hemagglutinin to sialic acid receptors of the host, thereby reinstating the antiviral property.Metal nanoparticles, including silver, copper, and gold, have previously shown antiviral efficacy over a range of enveloped viruses.85 Met2 and Zn, which generate excess reactive oxygen species (ROS). Multiple studies have demonstrated the virucidal properties of ROS either by direct oxidative damage leading to virus disintegration or various other non‐oxidative pathways. SARS‐CoV‐2 is susceptible to reactive oxygen‐mediated photodegradation by TiO2 and Zn nanoparticles. Park et al. evaluated the virucidal efficacy of surface coatings formulated from photo‐activated fluorinated TiO2 against human norovirus and showed effective inhibition of MS2  when exposed to residual ultraviolet A (UVA). These findings highlight the potential use of TiO2 and Zn nanoparticle surface coatings to sterilize surfaces outdoors in sunlit areas or indoors under fluorescents.Another strategy of viral deactivation is the use of metal oxides such as TiOpathways.91 SAR However, the virucidal property of nanoparticles may be compromised depending on the nature of the coating material. Iron oxide nanoparticles bind and interfere with sulfur‐bearing residues on proteins presented in viral–host cell entry. Silver, iron, other metal nanoparticles, or the combination bind in vulnerable disulfide regions of SARS‐CoV‐2 spike protein and thus inactivate the virus. A hybrid coating containing metal cations such as copper, iron, and zinc displayed a strong broad‐spectrum antibacterial effect against nosocomial infections. These coatings can be applied in healthcare settings to protect frequently touched surfaces.Additionally, pristine metallic nanoparticles have been used against both enveloped and non‐enveloped viruses.94 How Graphene composites with antimicrobial and antiviral metals have been investigated as surface coatings. Jana et al. demonstrated the efficacy of copper–graphene nanocomposites as an antiviral coating by dip‐coating tempered glass in a copper–graphene solution. Another study demonstrated that surfaces modified with graphene using plasma‐enhanced chemical vapor deposition (CVD) prevented biofilm formation through the vertical orientation of the graphene nanosheets. The nanosheets protrude from the surface, penetrating bacterial cells and thereby preventing their attachment.Graphene‐based nanomaterials have also been widely explored for antiviral applications. Graphene oxide (GO) and reduced graphene oxide (rGO) nanosheets contain negatively charged groups which contribute to their antiviral properties. Specifically, these groups bind to virions through electrostatic interactions and subsequently deactivate them through their nanoscale sharp edges.98 Gra However, a prominent disadvantage of these 3D printed surfaces is that they exhibit high virus attachment and stability for up to 72 h. The incorporation of virucidal nanoparticles in the polymer matrix used for 3D printing can help overcome this challenge. The functionality imparted by the nanoparticles will depend on the number of nanoparticles added and printing homogeneity. For example, antimicrobial medical devices can be engineered using copper nanocomposite additives in the polymer solution to produce an antimicrobial PLA filament. 3D printing technology can also be used to fabricate facemasks with anti‐viral activity. Incorporation of nanoparticles such as TiO2 and graphene could potentially impart photothermal functionality, thereby allowing for the effective manufacturing of self‐sterilizing PPE.The use of nanoparticles as virucidal agents would be advantageous in PPE, such as face masks and face shields. Notably, the use of nanoparticles such as copper and gold as additives in 3D printing carries a significant potential to produce more antiviral PPE. 3D printing has been realized as a vital technology in the fight against COVID‐19, during which conventional production chain and distribution systems for PPE faced significant challenges in ramp‐up. To meet supply demands, 3D printing, also known as additive manufacturing, emerged as a means to fill the gap.101 Ho Further development of such biosensors could allow for early detection of virus exposure and alert healthcare workers to decontaminate the PPE before doffing. Fabrication of PPE with both self‐cleaning and sensing capabilities could prove an effective way to protect against respiratory viruses and merits further study.Integration of wearable biosensors with PPE is another effective approach to enhance virus mitigation. For example, Kinnamon et al. developed a screen‐printed graphene oxide biosensor to detect environmental exposure to influenza A that could be incorporated with clothing, gloves, and other textiles.104 Fu5.2 Similar coating techniques have also been effective on hard polyethylene and soft polyester, polyacrylonitrile, and cellulosic materials. Notably, the application of polyethyleneimine coating onto cellulose fibers has given rise to new designs for low‐cost, high‐efficacy medical masks with anti‐viral properties. It is of note that most of the known polymeric coatings with antiviral properties are synthetic cationic polymers. However, there is evidence that the antiviral effect of the coating may be enhanced by complementing the antiviral layer with an anionic antibacterial polymer in a layer‐by‐layer approach. Polymeric materials may be directly grafted onto the substrate. Natechin, a simple polyphenol, has also been grafted onto sanitary wipes to confer virucidal capability. Similarly, polyethyleneimine was directly polymerized onto silica particles to confer antiviral activity. Other virucidal materials such as metals are more challenging to apply on surfaces than polymers. The most straightforward approach is to formulate these materials as a solution or emulsion with polymers that can be used as a surface coating. This approach has been demonstrated with simple antiviral compounds such as chlorine dioxide. Solutions of silver ions and polymer have also been electrospun into polymeric fibers containing silver particles. For materials that cannot be stably contained in a solution or emulsion, nanoparticles can be used first to encapsulate the antiviral agent. In a recent paper by Hodek et al., silver, copper, and zinc were encapsulated in a solution of methyl methacrylate, which was then coated onto a substrate and polymerized into a poly(methyl methacrylate) (PMMA) film containing the metals. Yet another approach is the covalent modification of the coating polymer to attach the antiviral material. For example, quaternary ammonium compounds can be immobilized onto hyperbranched polymers and applied to glass and plastic surfaces. Bioaerosols deposited on the surface may either become immobilized and unable to resuspend if bound to cell‐mimicking structures on the nanoparticles or become inactivated before leaving the surface.Compared to other virucidal materials, polymeric materials have superior practicality due to their rheological properties, which allow deposition by a simple dip‐coating process. This was recently demonstrated by Haldar et al. using N,N‐dodecyl methyl‐polyethyleneimine (PEIs), and derivatives, which were painted onto a glass surface that deactivated influenza viruses with nearly 100% efficiency.105 Sico‐ethylene) generated reactive oxygen species in daylight active vitamin K moiety. This surface coating on PPE exhibited excellent antiviral activity and deactivated pathogens in deposited droplets, hence preventing secondary infection. Recently, a dual functioning hydrophilic surface coating was developed to capture incoming pathogen‐laden droplets and prevent the resuspension of droplets from the surface. The polymer‐based coating constitutes a mixture of polyelectrolyte PAAm‐DDA and non‐ionic surfactant alkyl polyglycosides. The study demonstrated the versatility of the coating, with the ability to be applied to substrates with different material compositions, wettability, roughness, and geometries. Moreover, the incorporation of Cu2+ ions renders an antiviral property to the coating. Similarly, coatings and chemical modification of fibers have enhanced the HEPA filter efficiency. HEPA and HVAC filters can be covered with hydrophilic coatings to improve the capture of virus‐laden aerosols and thus prevent the escape and redistribution of pathogens into airstreams. In another study, functionalization of polyphenols like tannic acid on filters exhibited superior capture efficiency of influenza virus up to 2723 pfu/mm2 in 10 min compared to the non‐functionalized HEPA filter. In general, indoor floor carpets exhibit a high resuspension rate of pathogen‐laden aerosols. Studies have shown that floors covered with polyvinyl chloride significantly reduce the resuspension of Bacillus atrophaeus spores from the surface. Moreover, addition of fluorosurfactants to the floor finishing materials can enhance the surface wettability by reducing its interfacial tension. These surface coatings are speculated to increase the adhesion force between the settled respiratory droplet and the floor, minimizing resuspension.The advancements of self‐sterilizing materials can also be applied as coatings on the protective personal equipment clothing of health care workers. In one study, a photosensitive antiviral layer of a nanofibrous membrane with polyacrylonitrile and poly films. GNEC was produced by ultra‐sonic extrusion and then distributed on melt‐blown fibers of thermoplastics, including polypropylene. The surface demonstrated superhydrophobicity and could inactivate any remaining virus due to its photosterilizing ability when exposed to sunlight. With an improved understanding of the risk posed by resuspension, careful selection of materials and surface modifications should be considered an instrumental strategy in minimizing secondary infection sources.Superhydrophobicity has also been explored as a means to prevent adhesion of viral particles onto a surface. Superhydrophobic surfaces, characterized by high water contact angles, replace solid–liquid contact with liquid–air interfaces, thereby lessening contact of the surface with the viral‐laden droplets. In a study by Zhu et al., a coating solution of 2.5 w/w% hydrophobic silica nanoparticle dispersed in ethanol was prepared and applied by dip coating onto different substrates, including glass, plastic, and face masks. In these coated surfaces, SARS‐CoV‐2 attachment was decreased by 99.99995% compared to the bare surfaces.117 Si62O2), which is unsustainable and leads to environmental toxicity. Self‐cleaning materials based on photothermal or photochemical properties provide an alternative to the conventional means of sterilization and significantly reduce chemical waste due to their reusability. Superhydrophobic coatings that prevent adhesion of respiratory droplets on surfaces also prove to be effective strategies in hindering fomite transmission and infection risk by the resuspension of viral‐laden aerosols.Respiratory infections are mainly transmitted via virus‐laden droplets and aerosols. Our review examined the key mechanisms of aerosol generation, ranging from direct mechanisms such as coughing and sneezing to more indirect mechanisms such as medical procedures and toilet plumes. We have also discussed secondary aerosolization, which is influenced by human activities and environmental factors such as temperature and humidity. A wide range of material technologies can be implemented to prevent viral transmission via bioaerosols. We have discussed recent trends and breakthroughs in materials‐based approaches for countering disease transmission through bioaerosols. For example, metal nanoparticles have shown excellent virucidal properties and are particularly effective in surface layer applications, immobilizing bioaerosols and preventing further resuspension. The emerging use of nanotechnology and other virucidal materials in the fight against COVID‐19 and other respiratory diseases dominated by airborne transmission is of notable interest. While current PPE provides some level of protection to users, transmission is yet made possible by contact, for example, touching mucosal surfaces after removing a mask. The resuspension of aerosols from droplets that were previously deposited on surfaces poses a significant risk of disseminating infection. This is especially the case with SARS‐CoV‐2, which demonstrates long survival times on surfaces. Therefore, the use of virucidal coatings and different nanomaterials can be an effective strategy for mitigating transmission. The current strategy of prevention rely on the use of single‐use PPE or sterilization by chemical means (e.g., bleach, HThe use of nanoparticles with virucidal properties can be coupled with advancements in additive manufacturing. The addition of virucidal nanocomposites into the polymer matrix used for 3D printing can lead to the production of self‐sterilizing PPE, which will be pivotal in mitigating virus transmission. The integration of electrospun nanofibers in indoor air filters can be an effective approach to improving the filtration efficiency of virus‐laden aerosols. The small diameter and layer thickness of nanofibers reduce the airflow resistance and increase the inertial impaction of the particles across the filter. However, a significant drawback of these fibers is their reduced filtering capacity. Increasing the filter surface area by adopting different shapes over flat filters in HEPA can bypass this challenge. The functionalization of electrospun nanofibers with antiviral materials in HEPA or HVAC filters by dip coating or chemical crosslinking can deactivate the captured virus‐laden droplets. Therefore, installing such filters can effectively improve filtration efficiency and attenuate the transmission risks in indoor spaces such as airplanes and hospitals. Careful consideration of the existing and emerging technologies will allow for effective countermeasures to prevent the resuspension of viral droplets. These technologies can prove instrumental in preventing virus dissemination and hold potential against pandemic outbreaks. Overall, we expect this review to offer a roadmap for preventing respiratory viral infections by providing a greater understanding of bioaerosol‐based transmission mechanisms and suggesting effective countermeasures.The authors declare no conflict of interest.


Cypovirus (Reoviridae); the strain was isolated from Dendrolimus sibiricus, possessing attractive features as a candidate for mass production of biological agents for lepidopteran-pest control. We describe the morphological, molecular, and ecological features of the new Cypovirus strain. This strain was found to be highly virulent to D. sibiricus  and to have a relatively wide host range . The virus strain showed a strong interaction with a nontoxic adjuvant , which decreased the lethal dose for both main and alternative hosts, decreased lethal time, and may expand the host range. Moreover, we demonstrated that the insecticidal features were preserved after passaging through the most economically suitable host. By providing strong arguments for the possible use of this strain in pest control, we call on virologists, pest control specialists, and molecular biologists to give more attention to the Cypovirus genus, which may lead to new insights in the field of pest control research and may provide significant advantages to compare with baculoviruses and Bacillus thuringiensis products which are nowadays main source of bioinsecticides.Now more than ever researchers provide more and more evidence that it is necessary to develop an ecologically friendly approach to pest control. This is reflected in a sharp increase in the value of the biological insecticide market in recent decades. In our study, we found a virus strain belonging to the genus IMPORTANCE In this article, we describe a newly discovered cypovirus strain that displays features ideally suited for the development of a modern biological insecticide: high potency, relatively broad host range, true regulating effect, flexible production (possibility to choose host species for production), interaction with enhancing adjuvants, and ecologically friendly. Based on an alignment of CPV genomes, we suggest that the enhanced host range of this new strain is the sequence of evolutionary events that occurred after coinfections involving different CPV species within the same host. These findings suggest that we need to positively reconsider CPVs as prospective agents as biocontrol products. The market size of agricultural biologicals was estimated to be $8.8 billion in 2019 and is projected to grow at a CAGR of 13.6% and reach $18.9 billion by 2025 . Detailed analysis of the structure of this market reveals unequivocal dominance of Bacillus thuringiensis (Bt) based on the offered products  are free from this disadvantage owing to vertical transmission via survival of some hosts after infection  genus (Reoviridae family), which has been shown to possess important features in terms of its effectiveness, productivity, host range, production prospects, interaction with an adjuvant, and overall good potential for the organic-food industry. CPVs have segmented double-stranded RNA genomes  that are about 20 to 30 kbp in size. Cypovirus virions are single-shelled capsids and have icosahedral shapes  structures, polyhedra, during the late stages of infection . Such intense research attention has given rise to a new scientific field related to baculoviruses: baculovirus-based in vitro expression systems, which enable investigators to produce target proteins in appreciable amounts  (DsCPV-1), which is a major forest pest in boreal forests of Asia. D. sibiricus is an economically important pest that has attracted much attention, not only from scientists where this pest occurs naturally  in 2020. Light microscopic analysis of the dead larvae revealed many polyhedral occlusion bodies with a size of 1.5 to 2.0 μm (D. sibiricus) showed LD50 of 25 polyhedra per larva at 12 days . The genome encodes 10 proteins, including four structural capsid proteins , two constituents of transcription enzyme complex (RNA-dependent RNA Polymerase and NTPase/VP4), and four putative nonstructural proteins . Phylogenetic trees obtained independently for each of the proteins from a wide range of CPVs assigned the virus to the CPV 1 group . Nevertheless, substantial variation in the topology of some CPV groups across the inferred trees was observed.D. punctatus CPV-1 (DpCPV1), because all their proteins, except A-spike protein, share more than 99% identity (Table S1). Interestingly, A-spike protein, which is implicated in receptor binding and membrane penetration . The same mosaicism is clearly observable in multiple sequence alignment of five available complete CPV-1 genomes: e.g., the third segment of DsCPV-1 is much closer to LdCPV-1 than to DpCPV-1 (P = 3e-276).DsCPV-1 seems to be the closest relative of etration , is most DpCPV-1 . Togethe DpCPV-1 ; Fig. S2P. brassicae, M. brassicae, H. cunea, L. dispar, and M. sexta are susceptible to DsCPV-1 infection, whereas O. nubilalis, G. mellonella, L. sticticalis, and H. armigera are not affected by the virus challenge  revealed that even at a dose as low as 0.5 polyhedra per larva , the virus can kill half of the treated population. This high level of infectivity could be a consequence of the high sensitivity of the main host or/and successful horizontal transmission of the virus between individuals owing to the presence of mature occlusion bodies in host feces, as we observed in this study and as reported earlier  even though this virus replicates only in midgut tissue –11, and – earlier . The vir earlier –29.M. sexta, the full range of host response  was observed within 1 order of magnitude of viral titer dilution, while this window was much wider for the initial host  by initiating normal pathogenesis in a susceptible host. We indicate the actual sensitive hosts within the lepidopteran evolutionary tree , and mosial host . Thus, tpphirina . Howeverpphirina . It is kunctatus , Bombyx byx mori , and L. . dispar ; howeverxpansion . The posxpansion , 34. Whein vivo in the most economically suitable inexpensive host species (the current problem with mass cultivation of entomopathogenic viruses in cell lines [the cost of the culture medium] is not solved yet). For example, in our study, M. sexta proved to be a better candidate for this purpose because it has large quickly developing larvae, does not have diapause, and can be reared on the relatively inexpensive standard diet. The passaging of DsCPV-1 via M. sexta  preserved the pathogenicity toward the main host. We did not quantitatively analyze the virulence against D. sibiricus after the passaging via M. sexta in this study because of the limited number of D. sibiricus larvae available for the study. Even though the passaging through an alternative host will decrease the virulence toward the main host or another susceptible lepidopteran species, the virulence will still be acceptable as long as the cost of virus propagation is attractive for its production. Thus, all the above findings about DsCPV-1 should considerably increase the flexibility of viral-insecticide production and are suggestive of good prospects of DsCPV-1 as a biological insecticide against lepidopteran pests with wide applicability because this virus has a true regulatory effect on pest population dynamics.This fundamental finding may form the basis for the following practical implications. First, the DsCPV-1 strain reported here may be considered an agent for population management of economically important lepidopterans pests with wide host susceptibility within the order. This means that a universal scheme of production of a viral insecticide may be implemented to create a viral product for a broad pest control market. This will positively affect the price of the insecticide and its profit margin. Second, it is possible to organize mass production of this strain 50 of the hosts, and this parameter is also important for the protective ability of pest control products. As mentioned in the Introduction, at present, there are microbial products on the pest control market that possess a similar set of features. These are dominant insecticides based on B. thuringiensis . This ability is crucial for the control of polyvoltine insect pest species.Our data are consistent with the results of another study , which i36–ngiensis . Accordingiensis , fairly ngiensis , relativngiensis , our newIn light of DsCPV-1’s broad host range, an important question is the potential risk of its use for nontarget species, including humans. Even though some genera of the family Reoviridae can infect vertebrate or even mammalian organisms , 11, rep9–In conclusion, we would like to draw virologists’ attention to CPVs in general and to the CPV-1 group in particular for research on the host range of these viruses , their safety for nontarget species  , 10, andOur experimental approach involved several steps: (i) isolate and describe the morphological and molecular features of the isolated virus; (ii) reinfect specimens of the initial host species to document the virus’ pathological features; (iii) study the potential host range of this new viral strain, focusing on species of economic importance; (iv) study the interaction between the virus and a nontoxic chemical adjuvant-enhancer when tested against the original host species and alternative host species; and (v) assess the possibility of successfully infecting the initial host species after passing the virus via alternative host species (in the context of mass production technology).(i) Virus isolation. The virus was isolated from dead D. sibiricus larvae collected in 2020 in fir-cedar forests located at the foothills of the Eastern Sayan . About 500 overwintered fourth/fifth-instar larvae were field-collected in the spring and brought to the laboratory. Then, during the rearing of postdiapause larvae, we monitored mortality and found that about 100 out of 500 were dead. The first identification of the virus was performed by microscopic analysis of a rough imprint of the content of dead larvae on a histological slide. For subsequent manipulations with the virus, 50 dead larvae with obvious viral infection symptoms  were crushed in distilled water, and then polyhedral occlusion bodies were separated from rough debris by filtration through gauze, with subsequent centrifugation at 20,000 × g for 20 min. The obtained virus samples were then used for microscopy, genomic sequencing, and bioassays. Only dead larvae were used for polyhedra isolation.(ii) Light microscopy. An aqueous suspension of polyhedral occlusion bodies was examined under a light microscope  with oil immersion at 1,000× magnification. Nomarski contrast was employed for better visualization of the shape of the occlusion bodies.(iii) Electron microscopy. The extracted occlusion bodies were fixed in suspension by the addition of an equal volume of an 8% paraformaldehyde solution. The mixture was incubated at 4°C for 24 h. Then the polyhedra were washed with Hanks’ solution, additionally fixed with a 1% osmic acid solution, dehydrated in increasing concentrations of ethanol and acetone, and embedded into the Epon–Araldite mixture. Semithin and ultrathin sections were obtained on a Reichert-Jung microtome (Austria). Semithin sections were stained with an azure-II solution, viewed under an AxioImager Z1 light microscope , and areas of interest were selected for subsequent ultrastructural analyses. Ultrathin sections were counterstained with uranyl acetate and lead citrate. Electron microscopy was carried out using a JEM 1400 electron microscope . Photos were taken with a Veleta digital camera . Image analysis was performed in the iTEM software .(iv) Complete genome sequencing. Nucleic acids were extracted from purified viral polyhedra using the ExtractRNA reagent  following the manufacturer's instructions. Two μL of aqueous glycogen (20 mg/mL) were used as a co-precipitator. The precipitate was dissolved in 30 μL of deionized water and utilized as a template in a reverse-transcription reaction to synthesize cDNA according to the SISPA protocol  and according to Djikeng et al.  assembler with default parameters. Multiple-sequence alignment of CPV genomes was performed using the MAFFT (v7.407) algorithm. Maximum likelihood trees were inferred using RAxML-NG  within tPrediction of recombination signals and evaluation of their statistical significance were conducted by the 3SEQ  algorithNCBI GenBank accession numbers for the complete genomes of type 1 CPVs used in the study are provided in Table S1.D. sibiricus.(v) A bioassay of DsCPV-1 against the main host species: (a) 5.1. Half-lethal dose and median lethal time. We used the population of D. sibiricus collected in fir-cedar forests located at the foothills of the Eastern Sayan. For the bioassay, we obtained the next generation  of the insects under lab conditions. The larvae were reared at 24°C and 40% to 60% relative humidity under the 16:8 light:dark regime and were fed 2-year-old shoots of the fir Abies sibirica Ledeb.7, 106, 105, 104, and 103 polyhedra per milliliter. Polyhedra were isolated as described above. To inoculate the larvae with the virus, the droplet feeding method was applied (50) of the inoculated larvae were determined using the drc software package  was determined by Kaplan–Meier survival analysis followed by the logrank test with Holm–Sidak adjustment.For infection, we conducted a serial dilution experiment. In particular, the following virus concentrations in aqueous suspensions were employed: 10 applied . Second- package . Differe(b) 5.2. DsCPV-1 productivity. For this assay, we used larvae collected in the larch forests of the Baikal region because the stock from the Sayan D. sibiricus population was limited in this study. The larvae were reared under the same conditions as described above (except for the host plant) and were fed the shoots of the larch Larix sibirica Ledeb.7 polyhedra/mL. The infected and control groups contained 30 individuals each. The polyhedra were isolated from dead larvae by crushing a larvae body in a fixed volume of water. Then, the suspension of the homogenate (without filtration to avoid the loss of occlusion bodies) was diluted, and the occlusion bodies were counted on a hemocytometer at 400× magnification. Viral productivity was determined as the number of polyhedra per larva.For infection, fifth-instar larvae were individually fed 2 μL of a suspension of the virus in a colored 10% aqueous sucrose solution. The virus concentration in the suspension was 2 × 10(vi) Determination of the host species range. The experiment involved larvae of nine species of Lepidoptera from six families (except for the main host). The choice of host species was based on two main principles: (i) the economic importance of the lepidopteran pest and (ii) the evolutionary distance between families (to estimate the coverage of susceptible host species). Peroral infection was carried out in two ways: drop-feeding and diet-incorporation. Drop-feeding consisted of feeding the insects a drop of a virus suspension  Lymantria dispar.L. dispar eggs were collected in the spring from wild birch stands in Novosibirsk Oblast, Russia. Next, the eggs were kept in a refrigerator at 4°C during winter diapause. The hatching of larvae was synchronized with the budburst of birch leaves (first third of May) according to Martemyanov et al.  Pieris brassicae. Its eggs were collected in a cabbage field (one of the untreated fields) on a farm in Novosibirsk Oblast, Russia. The lower leaves of white cabbage (Brassica oleracea L.), grown in the laboratory, served as feed for the insects. Larvae were reared at 24°С to 25°С and 50% to 60% humidity under the natural photoperiod.(c) Ostrinia nubilalis. We used insects from a lab population at the All-Russian Institute of Plant Protection . The rearing of larvae was performed on an artificial diet following the procedure of Frolov and coauthors (oauthors .(d) Hyphantria cunea. Larvae of the fall webworm H. cunea were collected on mulberry trees in Krasnodar Oblast (Russia) in August 2021 at the egg stage. Larvae were maintained in plastic 2-L containers and fed with mulberry leaves at 24°C under the natural light/dark regime.(e) Mamestra brassicae. In this experiment, larvae of the first (F1) generation of the laboratory population were used. The larvae of the parental population were collected in a cabbage field on a farms in Novosibirsk Oblast, Russia. Lower leaves of white cabbage (B. oleracea L.), grown in the laboratory, served as feed for the insects. The insects were reared at 24°С to 25°С and 50% to 60% humidity under the natural photoperiod.(f) Manduca sexta. Insect eggs together with artificial feed and the protocol of rearing were kindly provided by T-REX Co. (Russia). The insects were reared at 24°С to 25°С and 50% to 60% relative humidity under the 16:8 light:dark regime.(g) Loxostege sticticalis. Larvae of the second (F2) generation of the laboratory population were used. The larvae of the parental population were collected on a forest edge in Krasnoyarsk Krai (Russia). The larvae were reared at 24°C and a relative humidity of 40% to 60% under the 16 h:8 h light:dark regime and were fed burdock Arctium lappa L. leaves.(h)Galleria mellonella. Insect larvae were kindly provided by the insectarium of the Institute of Systematics and Ecology of Animals, the Siberian Branch of the Russian Academy of Sciences (Novosibirsk). Larvae were reared at 28°C and 60% relative humidity on a 12 h:12 h light:dark cycle and were fed an artificial nutrient medium. A detailed description is given by Dubovskiy et al. Helicoverpa armigera. Larvae of the first (F1) generation of the laboratory population were used. Pupae of the parental population were collected in Uzbekistan. The larvae were reared on an artificial diet under natural illumination conditions.D. sibiricus by the virus passaged through the M. sexta host.(vii) Challenging the main host (a) 7.1. Passaging and virus isolation from M. sexta. Middle-instar larvae of M. sexta we infected by the initial virus via diet-incorporation. The feed was supplemented at the concentration of 107 polyhedra/mL, 1 mL per 20 larvae. Dead larvae were harvested and crushed, and the virus was purified according to the procedure described in subsection (i) Virus isolation.(b) Challenging the main host D. sibiricus by the virus passaged through M. sexta. Second-instar larvae of D. sibiricus were employed for this purpose. We used larvae of a filial generation hatched in the laboratory from the parental population that was collected in fir-cedar forests located at the foothills of the Eastern Sayan. The larvae were reared at 24°C and 40% to 60% relative humidity under the 16 h:8 h light:dark regime and were fed 2-year-old shoots of the fir A. sibirica.4 polyhedra per larva following the protocol described above. Larvae of the control group consumed a virus-free solution of sucrose. The experiment involved 14 experimental and 14 control individuals. We could not use more larvae for this bioassay because of the limited number of insects. The highest dose was chosen to qualitatively confirm the effectiveness of the virus against the main host. Mortality was recorded daily until the last individual died.For infection, second-instar larvae were individually fed 10(viii) Increasing the effectiveness of the virus by optical brightener Blankophor. Larvae of three lepidopteran species were subjected to this experiment: D. sibiricus, L. dispar. Drop-feeding was utilized as the infection method to assess the effect of Blankophor  on larval mortality from the viral infection, we conducted experiments with the following groups of larvae: (i) a 10% sucrose solution; (ii) a solution containing 0.5% of Blankophor and 10% of sucrose; (iii) a series of 10-fold dilutions of virus suspensions from 103 to 107 polyhedra/(mL of the 10% sucrose solution); and (iv) virus suspensions in a solution containing 0.5% of Blankophor and 10% of sucrose. The data are presented together with data on infection of the same species without the optical brightener.


Cross-modal correspondence has been consistently evidenced between shapes and other sensory attributes. Especially, the curvature of shapes may arouse the affective account, which may contribute to understanding the mechanism of cross-modal integration. Hence, the current study used the functional magnetic resonance imaging (fMRI) technique to examine brain activity’s specificity when people view circular and angular shapes. The circular shapes consisted of a circle and an ellipse, while the angular shapes consisted of a triangle and a star. Results show that the brain areas activated by circular shapes mainly involved the sub-occipital lobe, fusiform gyrus, sub and middle occipital gyrus, and cerebellar VI. The brain areas activated by angular shapes mainly involve the cuneus, middle occipital gyrus, lingual gyrus, and calcarine gyrus. The brain activation patterns of circular shapes did not differ significantly from those of angular shapes. Such a null finding was unexpected when previous cross-modal correspondence of shape curvature was considered. The different brain regions detected by circular and angular shapes and the potential explanations were discussed in the paper. Plenty of literature has provided evidence that shapes’ curvilinearity (roundedness and angularity) may have consistent cross-modal correspondences with other sensory attributes . For insPeople generally prefer circular stimuli over angular ones . The geovia a skeletal structure located in V3 and lateral occipital cortex for perceptual organization and object recognition  can lead to different preferences and affective effects with cross-modal experiments . What brIn our experiment, a total of 12 subjects volunteered to participate in the experiment, including three males and nine females. The average age of the participants is 21.75 ± 0.62 (from 21 to 23) years old. All participants had normal or corrected to normal vision and reported no history of neurological or psychiatric disorder. All participants were well informed about the study’s procedures and provided informed written consent. The study was approved by the Ethics Committee of the No. 2 People’s Hospital of Changshu (license number 2018–68). All participants received payments for their time.The basic geometric shapes with different curvatures were applied. Circular shapes included a circle and an ellipse. Angular shapes contain triangles and stars. The two types of shapes are comparable in contrast, color, and size when presented on display .The experiment contained four blocks, and each block included six trials. In each trial, participants watched one geometric shape for 6 s, then rested for 14 s. Each block repeated, displaying the same shape six times and lasted 120 s. The whole experiment lasted around 8 min. The order of the blocks was balanced among the participants.3.Structural and functional MRI data were collected using the GE Discovery MR750W 3.0T scanning system. The scanner is with an 8-channel head coil. During the scanning process, the participants quietly lay on the back of the magnetic resonance examination bed, fixing the head inside the head coil with foam padding, and wearing earplugs to reduce machine noise. The participants watched the visual stimuli through a reflector mirror mounted on the head coil. Through the mirror, the visual stimuli were reflected from the projector screen, placed outside the gate of the MRI. For structural imaging, high-resolution T1 weighted scans were acquired. The 3D T1 BRAVO_SPM volume sequence was applied with TR = 8.5 ms, TE = 3.2 ms, flip angle = 12°, FOV = 24 cm, 256 × 256 matrix size, and 1 mm slice thickness. The MR sequence for T2-weighted functional imaging was acquired using TR = 2000 ms, TE = 30 ms, flip angle = 90°, scan resolution of 64 × 64, 33 slices, intervals of 2 mm with slice thickness = 3.6 mm, FOV = 24 cm, voxel size = 3.75 × 3.75 × 3.75 mm1 and DPAIBI toolbox 2 based on Matlab 2012b 3 platform.The preprocessing and statistical analysis of NMR data mainly used the SPM12 toolbox 3, and spatial smoothing . Among them, the sequences in which the translation amount of the head movement range exceeds 2 mm or the rotation amount exceeds 2° are eliminated (around 6% of sequences are eliminated).The preprocessing of functional image data includes head movement correction, tissue segmentation, spatial registration and spatial Standardization ) standard space established by Montreal Institute of Neurology , with a resolution of 3 × 3 × 3 mmAfter the pretreatment, in the first-order analysis, the design parameters of the three conditions are combined with Hemodynamic Response Function (HRF) to construct the parameter model of a unified general linear model (GLM), and the head movement parameters are included in the model as covariates. At the first-order individual level, four groups of comparative analysis were carried out, namely geometric shapes (circular + angular) > resting condition, circular condition > resting condition, angular condition > resting condition, and circular condition > angular condition.t-test was performed. In the group single sample t-test, the non-parametric permutation test method is used for treatment, the number of permutations is 5000, and the cluster-forming threshold is set to P < 0.001. Finally, voxels with P < 0.05 are presented. All the above comparisons were performed on a custom gray matter removal template. The whole brain activation map was rendered by BrainNet view software.At the second-order group level, the four groups for each participant were grouped and combined by DPABI software, and then the group single sample We compared circular shapes vs angular shapes first. However, no significant brain activation was detected . We obtained the three-dimensional brain map, as shown in As can be seen from According to the details of the activated voxel group in In order to further examine the brain regions excited by circular and angular shapes, the brain activation maps of the two shapes were obtained, respectively. As shown in It can be seen from As shown in It can be seen from To sum up, the brain activation of circular shapes is mainly positive, while the activation of angular shapes is mainly negative. Viewing circular shapes and angular shapes may involve different neural computations.Circular shapes tend to be perceived as positive, while angular shapes tend to be perceived as negative . PreviouThe results showed that the brain regions activated by geometric shapes were mainly in the cuneus and cerebellar VI region. Cuneus is involved in basic visual processing, and Cerebellar VI is related to motor planning and coordination . The cerFor the brain activation of circular and angular shapes, circular shapes are mainly positive, while angular shapes are mainly negative. These observations suggest that the brain’s basis of circular and angular shapes processing involves different computations. The different, often neighboring, brain regions are more active for round versus for sharp surface, which also supports the different computation theroy, or a gradient-of-representation theories . HoweverWe also hypothesized that geometry is processed in the primary visual cortex and brain areas such as higher emotion. The current study emphasizes the role of emotion processing in angular and curved correspondence, which is also supported by neuroscience evidence, which emphasizes the role of emotion in multisensory perception and shape perception . HoweverOne limitation of this study is that it adopts a simple shape-viewing task. Moreover, in the geometric sense, only two types of figures are simple and have the same topological properties. Other than the curvature of the shape, the spatial frequencies, inked size and local contrast should be considered in future experiment design. In further studies, we may consider adopting a more sensitive experimental paradigm to identify the brain activation of circular and angular shapes, and localize the ROI at amygdala and cuneus. Moreover, the number of subjects in this study is relatively small. More samples in the future study will guarantee better reliability and validity.The original contributions presented in this study are included in the article/The studies involving human participants were reviewed and approved by the Ethics Committee of the No. 2 People’s Hospital of Changshu. The patients/participants provided their written informed consent to participate in this study.LW, XL, LiH, QD, and PL conceived and designed the experiments and contributed to the writing of the manuscript. YL, LuH, and WS performed the experiments and analyzed the data. All authors contributed to the article and approved the submitted version.