Prebiotic Formation of Peptides Through Bubbling and Arc Plasma.

The abiotic synthesis of peptides, widely regarded as one of the key chemical reactions on the prebiotic Earth, is thermodynamically constrained in solution. Herein, a simulation of the lightning phenomenon on the sea surface using bubble bursting and arc plasma under ambient conditions enables dipeptide formation of six amino acids with conversion ratios ranging from 2.6% to 25.5%. Additionally, we observed the formation of biologically active tripeptides and investigated the stereoselectivity of the dipeptide formation reaction. By utilizing a mixture of 20 amino acids in the reaction, 102 possible dipeptides were generated. These results establish experimental constructions to mimic achievable prebiotic conditions and provide a credible pathway for endogenous biopolymer synthesis on prebiotic Earth.

Communication Strategies in Human-Autonomy Teams During Technological Failures.

OBJECTIVE: This study examines low-, medium-, and high-performing Human-Autonomy Teams' (HATs') communication strategies during various technological failures that impact routine communication strategies to adapt to the task environment. BACKGROUND: Teams must adapt their communication strategies during dynamic tasks, where more successful teams make more substantial adaptations. Adaptations in communication strategies may explain how successful HATs overcome technological failures. Further, technological failures of variable severity may alter communication strategies of HATs at different performance levels in their attempts to overcome each failure. METHOD: HATs in a Remotely Piloted Aircraft System-Synthetic Task Environment (RPAS-STE), involving three team members, were tasked with photographing targets. Each triad had two randomly assigned participants in navigator and photographer roles, teaming with an experimenter who simulated an AI pilot in a Wizard of Oz paradigm. Teams encountered two different technological failures, automation and autonomy, where autonomy failures were more challenging to overcome. RESULTS: High-performing HATs calibrated their communication strategy to the complexity of the different failures better than medium- and low-performing teams. Further, HATs adjusted their communication strategies over time. Finally, only the most severe failures required teams to increase the efficiency of their communication. CONCLUSION: HAT effectiveness under degraded conditions depends on the type of communication strategies enacted by the team. Previous findings from studies of all-human teams apply here; however, novel results suggest information requests are particularly important to HAT success during failures. APPLICATION: Understanding the communication strategies of HATs under degraded conditions can inform training protocols to help HATs overcome failures.

Radical-Induced Dissociation for Oligonucleotide Sequencing by TiO2/ZnAl-Layered Double Oxide-Assisted Laser Desorption/Ionization Mass Spectrometry.

De novo sequencing of oligonucleotides remains challenging, especially for oligonucleotides with post-transcriptional or synthetic modifications. Mass spectrometry (MS) sequencing can reliably detect and locate all of the modification sites in oligonucleotides via m/z variance. However, current MS-based sequencing methods exhibit complex spectra and low ion abundance and usually require coupled instrumentation. Herein, we demonstrate a method of oligonucleotide sequencing using TiO2/ZnAl-layered double oxide (LDO)-assisted laser desorption/ionization (LDI)-MS based on radical-induced dissociation (RID). ·CH2OH radicals can be produced on the surface of a TiO2/ZnAl-LDO matrix via ultraviolet light, inducing an attack on the active site of the oligonucleotide phosphate skeleton to create typical "a-, a-B-, c·-, d-, w-, and y"-type fragments. Compared with the spectra obtained via collision-based methods, such as collision-induced dissociation and higher-energy collisional dissociation, the LDI-MS spectra based on RID exhibit single-charged signals, fewer types of fragments, and a lower proportion of unknown noise peaks. We demonstrate full sequence coverage for a 6-mer 2'-O-methyl-modified oligonucleotide and a 21-mer small interfering RNA and show that RID can sequence oligonucleotides with modifications. Importantly, the mechanism responsible for the RID of the oligonucleotide phosphate skeleton was investigated through offline experiments, demonstrating consistent results with density functional theory calculations.

How Do Child ADHD Symptoms and Oppositionality Impact Parent-Child Interactions When Crossing Virtual Roads?

OBJECTIVE: This study examined how parents and children interact when crossing virtual roads together. We examined (1) whether children's inattention/hyperactivity and oppositionality and children's failure to jointly perform the task interfered with parents' efforts to scaffold children's road-crossing skill and (2) whether experience with the joint road-crossing task impacted children's subsequent performance in a solo road-crossing task. METHODS: Fifty-five 8- to 10-year-old children with and without attention-deficit/hyperactivity disorder and their parents first jointly crossed a lane of traffic in an immersive pedestrian simulator. Children then completed the same road-crossing task alone. Parents completed questionnaires about children's symptoms of inattention/hyperactivity and oppositionality. RESULTS: Analyses of the joint road-crossing task showed that when parents and children crossed different gaps, parents suggested and opposed more gaps and were less likely to use a prospective gap communication strategy (i.e., communicating about a crossable gap prior to its arrival). Crossing different gaps was also associated with increased expressions of negative affect among parents and children and an increase in collisions among children. Children's level of parent-reported oppositionality also predicted an increase in child defiance and parental redirection of child behavior. Analyses of children's subsequent crossing performance indicated that parents' use of a prospective gap communication strategy during the joint road-crossing task predicted selection of larger gaps during the solo crossing task. CONCLUSIONS: Not crossing through the same gap and increased levels of child oppositionality interfered with the scaffolding process, potentially informing future parent-based intervention efforts for increasing children's road-crossing safety.

Photocatalytic reduction-based liquid microjunction surface sampling-mass spectrometry for rapid in situ analysis of aromatic amines originating from azo dyes in packaging papers.

A rapid in situ analytical method was developed for the detection of generated carcinogenic aromatic amines from banned azo dyes utilizing a photocatalytic reduction-based liquid microjunction surface sampling (LMJSS)-mass spectrometry (MS) system. We utilized photocatalytic reduction under UV irradiation with TiO2 as catalyst to have rapid and mild reduction of azo dyes. The reaction conditions were optimized to have complete photocatalytic reduction within 2-5 min in pure methanol at room temperature. TiO2 was immobilized in the inner wall of the capillaries in the LMJSS system to achieve in situ sampling-online rapid reduction-MS detection for aromatic amines originating from azo dyes in packaging surface. The yields of in-tube photocatalytic reduction were near 100% by delivering the azo dye extracts through the capillary at 1 µL/min under UV irradiation. With this design, in situ analysis was completed within 2 min via direct MS detection and 7 min via liquid chromatography (LC)-MS detection. The detection limits for five aromatic amines originating from four different azo dyes were in the range of 1-17 mg/kg with relative standard deviations (RSDs) < 8.5%. In the application of the new method, four carcinogenic aromatic amines were detected and identified in three commercial packaging materials, and the quantitation results were comparable with those obtained by the conventional chemical reduction-LC-MS method (relative recovery, 81-121%). Moreover, due to the spatial resolution of the present method with a flow probe, MS imaging was achieved demonstrating clear azo dye patterns of a lab-made sample.

Bufadienolides from the Eggs of the Toad Bufo bufo gargarizans and Their Antimelanoma Activities.

Toads produce potent toxins, named bufadienolides, to defend against their predators. Pharmacological research has revealed that bufadienolides are potential anticancer drugs. In this research, we reported nine bufadienolides from the eggs of the toad Bufo bufo gargarizans, including two new compounds (1 and 3). The chemical structures of 1 and 3, as well as of one previously reported semisynthesized compound (2), were elucidated on the basis of extensive spectroscopic data interpretation, chemical methods, and X-ray diffraction analysis. Compound 1 is an unusual 19-norbufadienolide with rearranged A/B rings. A biological test revealed that compounds 2 and 4-8 showed potent cytotoxic activities toward human melanoma cell line SK-MEL-1 with IC50 values less than 1.0 µM. A preliminary mechanism investigation revealed that the most potent compound, 8, could induce apoptosis via PARP cleavage, while 5 and 6 significantly suppressed angiogenesis in zebrafish. Furthermore, an in vivo biological study showed that 5, 6, and 8 inhibit SK-MEL-1 cell growth significantly.

Let's Cross the Next One: Parental Scaffolding of Prospective Control Over Movement.

This investigation examined parental scaffolding of children's prospective control over decisions and actions during a joint perception-action task. Parents and their 6-, 8-, 10-, and 12-year-old children (N = 128) repeatedly crossed a virtual roadway together. Guidance and control shifted from the parent to the child with increases in child age. Parents more often chose the gap that was crossed and prospectively communicated the gap choice with younger than older children. Greater use of an anticipatory gap selection strategy by parents predicted more precise timing of entry into the gap by children. This work suggests that social interaction may serve as an important experiential mechanism for the development of prospective control over decisions and actions in the perception-action domain.

Harnessing Vehicle-to-Pedestrian (V2P) Communication Technology: Sending Traffic Warnings to Texting Pedestrians.

OBJECTIVE: We examined how sending mobile-device warnings to texting pedestrians when they initiate an unsafe road crossing influences their decisions and actions. BACKGROUND: Pedestrian texting has been identified as a key risk factor in pedestrian-vehicle collisions. Advances in sensing and communications technology offer the possibility of providing pedestrians with information about traffic conditions to assist them in safely crossing traffic-filled roadways. However, it is unclear how this information can be most effectively communicated to pedestrians. METHOD: We examined how texting and nontexting pedestrians crossed roads with continuous traffic in a large-screen, immersive pedestrian simulator using a between-subjects design with three conditions: texting, warning, and control. Texting participants in the warning condition received an alarm on their cell phone when they began to cross a dangerously small gap. RESULTS: The results demonstrate the detrimental influence of texting on pedestrians' gap selection, movement timing, and gaze behavior, and show the potential of warnings to improve decision making and safety. However, the results also reveal the limits of warning texting participants once they initiate a crossing and possible overreliance on technology that may lead to reduced situation awareness. CONCLUSION: Mobile devices and short-range communication technologies offer enormous potential to assist pedestrians, but further study is needed to better understand how to provide useful information in a timely manner. APPLICATION: The technology for communicating traffic information to pedestrians via mobile devices is on the horizon. Research on how such information influences all aspects of pedestrian behavior is critical to developing effective solutions.

Isolation and identification of l/d-lactate-conjugated bufadienolides from toad eggs revealing lactate racemization in amphibians.

Three pairs of bufadienolide l/d-lactate epimers (1-6) were isolated from the eggs of the toad Bufo bufo gargarizans. The structures were elucidated by using spectroscopic methods, X-ray diffraction analysis and a modified Mosher's method. Compounds 1-6 represent the first occurrence of lactate-conjugated bufadienolides in nature, and illustrate the existence of an enzyme-controlled epimerization from l- to d-lactate in amphibians. The biosynthetic pathways, in which two key enzymes might be involved (i.e., lactate racemase and acyltransferase), were proposed. In addition, the biological assays revealed that compounds 1-4 are potent cytotoxic agents against human gastric cancer cells BGC-823 and human lung cancer cells A549 with IC50 values in a range of 8.0 to 80.0 nM.

Neoantimycins A and B, Two Unusual Benzamido Nine-Membered Dilactones from Marine-Derived Streptomyces antibioticus H12-15.

An actinomycete strain (H12-15) isolated from a sea sediment in a mangrove district was identified as Streptomycesantibioticus on the basis of 16S rDNA gene sequence analysis as well as the investigation of its morphological, physiological, and biochemical characteristics. Two novel benzamido nonacyclic dilactones, namely neoantimycins A (1) and B (2), together with the known antimycins A1ab (3a,b), A2a (4), and A9 (5), were isolated from the culture broth of this strain. Compounds 1 and 2 are the first natural modified ATNs with an unusual benzamide unit. The structures of these new compounds, including their absolute configuration, were established on the basis of HRMS, NMR spectroscopic data, and quantum chemical ECD calculations. Their cytotoxicities against human breast adenocarcinoma cell line MCF-7, the human glioblastoma cell line SF-268, and the human lung cancer cell line NCI-H460 were also tested. All compounds exhibited mild cytotoxic activity. However, Compounds 1 and 2 showed no activity against C. albicans at the test concentration of 1 mg/mL via paper disc diffusion, while the known antimycins showed obvious antifungal activity.

Hyperoside ameliorates glomerulosclerosis in diabetic nephropathy by downregulating miR-21.

The purpose of this study was to investigate the therapeutic effects of hyperoside (Hyp) on glomerulosclerosis in diabetic nephropathy and its underlying mechanisms. Blood glucose, kidney mass, and renal function of mice were measured. Renal morphology was observed using hematoxylin and eosin, periodic acid - Schiff's, and Masson's trichrome stain. Fibronectin (FN) and collagen IV (COL IV) in kidney were determined by Western blot and immunohistochemical studies. Matrix metalloproteinases (MMP)-2 and -9 and tissue inhibitors of metalloproteinase (TIMP)-1 in renal tissues were detected on both the mRNA and protein levels. miRNA expression and artificial alterations by miRNA agomir transfection were evaluated to investigate the protective mechanism of Hyp in mesangial cells. Hyp effectively improved renal function and physiologic features of db/db mice. Hyp also ameliorated glomerulosclerosis by suppressing FN, COL IV, and TIMP-1 expressions and promoting MMP-9 and MMP-2 expressions. The change in MMP-9 mRNA expression was inconsistent with that in protein levels in kidney, indicating that there was a post-transcriptional regulation. Further exploration in vitro showed that miR-21 was downregulated by Hyp, increasing expression of its target, MMP-9. These results suggest that Hyp can ameliorate glomerulosclerosis in diabetic nephropathy by downregulating miR-21 to increase expression of its target, MMP-9.

Effectiveness of problem-based learning in Chinese pharmacy education: a meta-analysis.

BACKGROUND: This review provides a critical overview of problem-based learning (PBL) practices in Chinese pharmacy education. PBL has yet to be widely applied in pharmaceutical education in China. The results of those studies that have been conducted are published in Chinese and thus may not be easily accessible to international researchers. Therefore, this meta-analysis was carried out to review the effectiveness of PBL. METHODS: Databases were searched for studies in accordance with the inclusion criteria. Two reviewers independently performed the study identification and data extraction. A meta-analysis was conducted using Revman 5.3 software. RESULTS: Sixteen randomized controlled trials were included. The meta-analysis revealed that PBL had a positive association with higher theoretical scores (SMD = 1.17, 95% CI [0.77, 11.57], P < 0.00001). The questionnaire results show that PBL methods are superior to conventional teaching methods in improving students' learning interest, independent analysis skills, scope of knowledge, self-study, team spirit, and oral expression. CONCLUSIONS: This meta-analysis indicates that PBL pedagogy is superior to traditional lecture-based teaching in Chinese pharmacy education. PBL methods could be an optional, supplementary method of pharmaceutical teaching in China. However, Chinese pharmacy colleges and universities should revise PBL curricula according to their own needs, which would maximize the effectiveness of PBL.

Sequence-based identification of recombination spots using pseudo nucleic acid representation and recursive feature extraction by linear kernel SVM.

BACKGROUND: Identification of the recombination hot/cold spots is critical for understanding the mechanism of recombination as well as the genome evolution process. However, experimental identification of recombination spots is both time-consuming and costly. Developing an accurate and automated method for reliably and quickly identifying recombination spots is thus urgently needed. RESULTS: Here we proposed a novel approach by fusing features from pseudo nucleic acid composition (PseNAC), including NAC, n-tier NAC and pseudo dinucleotide composition (PseDNC). A recursive feature extraction by linear kernel support vector machine (SVM) was then used to rank the integrated feature vectors and extract optimal features. SVM was adopted for identifying recombination spots based on these optimal features. To evaluate the performance of the proposed method, jackknife cross-validation test was employed on a benchmark dataset. The overall accuracy of this approach was 84.09%, which was higher (from 0.37% to 3.79%) than those of state-of-the-art tools. CONCLUSIONS: Comparison results suggested that linear kernel SVM is a useful vehicle for identifying recombination hot/cold spots.

Isolation, identification, molecular and pathogenicity characteristics of an infectious laryngotracheitis virus from Hubei province, China.

Multiple outbreaks of avian infectious laryngotracheitis (ILT) in chickens, both domestically and internationally, have been directly correlate to widespread vaccine use in affected countries and regions. Phylogenetic and recombination event analyses have demonstrated that avian infectious laryngotracheitis virus (ILTV) field strains are progressively evolving toward the chicken embryo-origin (CEO) vaccine strain. Even with standardized biosecurity measures and effective prevention and control strategies implemented on large-scale farms, continuous ILT outbreaks result in significant economic losses to the poultry industry worldwide. These outbreaks undoubtedly hinder efforts to control and eradicate ILTV in the future. In this study, an ILTV isolate was successfully obtained by laboratory PCR detection and virus isolation from chickens that exhibited dyspnea and depression on a broiler farm in Hubei Province, China. The isolated strain exhibited robust propagation on chorioallantoic membranes of embryonated eggs, but failed to establish effective infection in chicken hepatocellular carcinoma (LMH) cells. Phylogenetic analysis revealed a unique T441P point mutation in the gJ protein of the isolate. Animal experiments confirmed the virulence of this strain, as it induced mortality in 6-wk-old chickens. This study expands current understanding of the epidemiology, genetic variations, and pathogenicity of ILTV isolates circulating domestically, contributing to the elucidate of ILTV molecular basis of pathogenicity and development of vaccine.

Ortho C-H Bond Activations in an Atmospheric Microwave Plasma Ion Source.

C-H bond ortho-substitution reaction has always been a significant and challenging topic in organic chemistry. We proposed a synthesis method based on microwave plasma torches. High-resolution mass spectrometry was used to monitor rapid reaction products. 2-Alkylbenzimidazole can be formed through the reaction of phenylnitrenium ion and nitriles on a millisecond scale. This reaction can achieve the one-step formation of benzimidazoles from benzene ring single-substituted compounds without the addition of external oxidants or catalysts. A similar C-H bond activation reaction can be accomplished with ketones. Meanwhile, the microwave plasma reactor was modified, and the resulting 2-methylbenzimidazole was successfully collected, indicating the device has good application potential in organic reactions such as C-H bond activation reaction.

Pleurotus ostreatus polysaccharide-mediated modulation of skin damage caused by microcystin-LR in tadpoles.

In this study, we aimed to evaluate the effect of dietary supplementation with edible mushroom (Pleurotus ostreatus)-derived polysaccharides on microcystin leucine-arginine (MC-LR)-induced skin damage in Pelophylax nigromaculatus tadpoles. Tadpoles were exposed to 1 µg/L daily MC-LR, with or without 5.0 g/kg of dietary P. ostreatus polysaccharides, for 30 days. P. ostreatus polysaccharide supplementation significantly increased the dermal collagen fibrils, increased tight junction protein gene expression, decreased the amount of MC-LR accumulation in skin tissues, attenuated oxidative stress, downregulated apoptosis-associated gene transcription, decreased eosinophil numbers, and downregulated transcription of inflammation-related genes (e.g. TLR4, NF-κB, and TNF-α). The composition of the skin commensal microbiota of MC-LR-exposed tadpoles supplemented with P. ostreatus polysaccharides was similar to that of the no-treatment control group. Lipopolysaccharide (LPS) content was positively correlated with the abundance of Gram-negative bacteria, including Chryseobacterium and Thauera. Therefore, P. ostreatus polysaccharides may alleviate MC-LR-induced skin barrier damage in tadpoles in two ways: 1) attenuation of oxidative stress-mediated apoptosis mediated by increased glutathione (GSH) content and total superoxide dismutase activity; and 2) alteration of the skin commensal microbiota composition to attenuate the LPS/Toll-like receptor 4 inflammatory pathway response. Furthermore, P. ostreatus polysaccharides may increase skin GSH synthesis by promoting glycine production via the gut microbiota and may restore the MC-LR-damaged skin resistance to pathogenic bacteria by increasing antimicrobial peptide transcripts and lysozyme activity. This study highlights for the first time the potential application of P. ostreatus polysaccharides, an ecologically active substance, in mitigating the skin damage induced by MC-LR exposure, and may provide new insights for its further development in aquaculture.

A PdPt nanoparticle-decorated thiol-functionalized MOF with high peroxidase-like activity for colorimetric sensing of D-glucose and chlorophenol isomers.

The peroxidase (POD)-like catalytic activity of various nanozymes was extensively applied in many significant fields. In this study, a thiol-functionalized MOF-loaded PdPt nanocomposite (UiO-66-(SH)2@PdPt) was fabricated, which possesses superior and selective POD-like activity with strong affinity towards H2O2 and 3,3',5,5'-tetramethylbenzidine under mild conditions. The POD-like property of UiO-66-(SH)2@PdPt was used to sensitively detect the concentration of D-glucose under near-neutral (pH = 6.5) conditions. The detection limit of D-glucose was as low as 2.7 µM, and the linear range of D-glucose was 5-700 µM. In addition, UiO-66-(SH)2@PdPt could accelerate the oxidative coupling chromogenic reaction of chlorophenol (CP) and 4-aminoantipyrine (4-AAP) in the presence of H2O2. Based on this phenomenon, a simple and visualized sensing array for the identification of chlorophenol contaminant isomers was further constructed to finally achieve the effective differentiation of three monochlorophenol isomers and six dichlorophenol isomers. Furthermore, a colorimetric detection method for 2-chlorophenol and 2,4-dichlorophenol was established. This work provides an effective means to improve the catalytic activity and selectivity of nanozymes by introducing an ideal carrier, which will be of significant value for the design of efficient nanozymes.

α-Cyano-3-aminocinnamic acid: A novel reactive matrix for qualitative and quantitative analysis of plant N-glycans by MALDI-MS.

N-glycans have a diversity of crucial biological roles in organisms. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has become an indispensable analytical instrument for biomolecules. However, due to the inherent low abundance, high structural heterogeneity, and poor ionization efficiency of N-glycans, as well as the extremely inhomogeneous co-crystal property using traditional matrices, the qualitation and quantitation of N-glycans by MALDI-MS remains challenging. In the present study, α-cyano-3-aminocinnamic acid (3-CACA) was reasonably designed and synthesized as a novel reactive matrix for N-glycan analysis. Combining with traditional matrix α-cyano-4-hydroxycinnamic acid (CHCA) as an acidic catalyst, a combinational matrix 3-CACA/CHCA was obtained with homogeneous co-crystallization and high derivatization efficiency, achieving the sensitive qualitation with the limits of detection low to femtomole and reproducible quantitation with good linearity (R2 > 0.998). As a result, the established method was successfully applied to the on-target derivatization and high-throughput quantification of N-glycans in eight varieties of the peach complex system, indicating that N-glycan has the potential to become a new biomarker for food allergy, and elucidating the prospective correlation between N-glycan epitopes and allergic reactions.

Fast and bioluminescent detection of antibiotic contaminants by on-demand transcription of RNA scaffold arrays.

Cell-free biosensors have inspired low-cost and field-applicable methods to detect antibiotic contaminants. However, the satisfactory sensitivity of current cell-free biosensors is mostly achieved by sacrificing the rapidity, which prolongs turnaround time by hours. Additionally, the software-based result interpretation provides an obstacle for delivering these biosensors to untrained individuals. Here, we present a bioluminescence-based cell-free biosensor, termed enhanced Bioluminescence sensing of Ligand-Unleashed RNA Expression (eBLUE). The eBLUE leveraged antibiotic-responsive transcription factors to regulate the transcription of RNA arrays that can serve as scaffolds for reassembling and activating multiple luciferase fragments. This process converted target recognition into an amplified bioluminescence response, enabling smartphone-based quantification of tetracycline and erythromycin directly in milk within 15 min. Moreover, the detection threshold of eBLUE can be easily tuned according to the maximum residue limits (MRLs) established by government agencies. Owing to this tunable nature, the eBLUE was further repurposed as an on-demand semi-quantification platform, allowing for fast (∼20 min) and software-free identification of safe and MRL-exceeding milk samples only by glancing over the smartphone photographs. Overall, the sensitivity, rapidity and user-friendliness of eBLUE demonstrate its potentials for practical applications, especially in resource-limited and household settings.

Temporal-spatial risk assessment of COVID-19 under the influence of urban spatial environmental parameters: The case of Shenyang city.

Respiratory infection is the main route for the transmission of coronavirus pneumonia, and the results have shown that the urban spatial environment significantly influences the risk of infection. Based on the Wells-Riley model of respiratory infection probability, the study determined the human respiratory-related parameters and the effective influence range; extracted urban morphological parameters, assessed the ventilation effects of different spatial environments, and, combined with population flow monitoring data, constructed a method for assessing the risk of Covid-19 respiratory infection in urban-scale grid cells. In the empirical study in Shenyang city, a severe cold region, urban morphological parameters, population size, background wind speed, and individual behavior patterns were used to calculate the distribution characteristics of temporal and spatial concomitant risks in urban areas grids under different scenarios. The results showed that the correlation between the risk of respiratory infection in urban public spaces and the above variables was significant. The exposure time had the greatest degree of influence on the probability of respiratory infection risk among the variables. At the same time, the change in human body spacing beyond 1 m had a minor influence on the risk of infection. Among the urban morphological parameters, building height had the highest correlation with the risk of infection, while building density had the lowest correlation. The actual point distribution of the epidemic in Shenyang from March to April 2022 was used to verify the evaluation results. The overlap rate between medium or higher risk areas and actual cases was 78.55%. The planning strategies for epidemic prevention and control were proposed for the spatial differentiation characteristics of different risk elements. The research results can accurately classify the risk level of urban space and provide a scientific basis for the planning response of epidemic prevention and control and the safety of public activities.