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Cancer nanovaccine is a frontier immunotherapy strategy, in which the delivery carrier can protect antigen and adjuvant from degradation, increase blood circulation half-life, and improve antigen permeability and presentation, thus enhancing the security and potency of nanovaccine. To address the barriers of antigen delivery, we design and fabricate a kind of intracellular pH-sensitive glycopolypeptide coordinated nanovaccine (OVA-HPGM-Mn) with ∼30% loading capacity of ovalbumin (OVA). The nanovaccine OVA-HPGM-Mn could specifically deliver antigen to dendritic cells (DCs) and effectively escape from endolysosomes to cytoplasm after 6 h of incubation, while the blank counterpart HPGM-Mn acted as an adjuvant to promote DCs maturation and increase the percentage of maturated cells to 26.5% from 11.8% in vitro. Furthermore, the mannosylated polypeptide nanovaccine prolonged the retention time of OVA for 72 h to facilitate 29.5% DCs maturation in lymph nodes, activated 48.8% CD8+T cells in spleen, increased the CD8+/CD4+T cell ratio twice to 1.06, and upregulated the levels of pro-inflammatory cytokines including TNF-α, IFN-γ, and IL-6, thus inhibiting the tumor growth of ∼80%. Consequently, this work provides a versatile strategy for the fabrication of glycosylated polypeptide coordinated nanomaterials for antigen delivery and cancer immunotherapy.

The collapse of goaf is one of the most serious geological disasters in cities where underground mineral resources are mined. The ground subsidence caused by the goaf limits the social and economic development of the area, while also endangering the safety of residents and property near the mining area. At present, support and grouting treatment methods are commonly used for the treatment of goaf. The cost of support treatment is relatively high, and it is difficult to control the collapse of the deeper goaf. Grouting treatment is suitable for conducting detailed investigations of underground spaces. The cost of complete grouting is high, and the timing of grouting termination is difficult to control. This paper aims to explore the optimization of grouting efficiency in the treatment of underground subsidence in goaf areas using the reserved pillar mining method. Through the stability calculation of the goaf pillars and roof, it can be concluded that the goaf pillars are unstable pillars under current conditions and are prone to damage under load interference. At present, surface subsidence has occurred in the goaf and requires treatment. Consider the comparison between the collapse control effect under different grouting rates and the complete grouting, and ultimately select the condition of 90% grouting rate to achieve the control effect. This conclusion can provide a certain theoretical reference basis for the treatment of similar goaf collapse, and has certain practical significance.

Abstract Infectious disease outbreaks transcend the medical and public health realms, triggering widespread panic and impeding socio-economic development. Considering that self-limiting diarrhoea of sporadic cases is usually underreported, the Salmonella outbreak (SO) study offers a unique opportunity for source tracing, spatiotemporal correlation, and outbreak prediction. To summarize the pattern of SO and estimate observational epidemiological indicators, 1,134 qualitative reports screened from 1949 to 2023 were included in the systematic review dataset, which contained a 506-study meta-analysis dataset. In addition to the dataset comprising over 50 columns with a total of 46,494 entries eligible for inclusion in systematic reviews or input into prediction models, we also provide initial literature collection datasets and datasets containing socio-economic and climate information for relevant regions. This study has a broad impact on advancing knowledge regarding epidemic trends and prevention priorities in diverse salmonellosis outbreaks and guiding rational policy-making or predictive modeling to mitigate the infringement upon the right to life imposed by significant epidemics.

The toppling deformation in bank slope of V-shaped Gorge reservoirs in Southwest China is very common. After the impoundment of the reservoir, geological disasters such as collapse and landslide may occur in toppling bank slope, which poses a threat to the normal operation of hydropower projects and personnel safety. Therefore, it is of great engineering significance to study its genetic mechanism and development law. The trenching of river valley is one of the main factors of bank slope toppling deformation. In the process of river action, the free face is formed on the slope, and the rock mass is unloaded to the free face, resulting in toppling. Taking the bank slope of a reservoir in the V-shaped Gorge area on the edge of the Qinghai Tibet Plateau in Southwest China as an example, this paper studies the relationship between river action and the development of toppling. According to the seven terraces formed on both banks of the river, the trenching of the river valley is divided into seven stages. The toppling development characteristics of each stage are analyzed by discrete element method. According to the development characteristics of toppling deformation category, the toppling deformation is divided into five stages, they are initial toppling deformation stage, toppling development stage, intensified toppling deformation stage, temporary stability stage and failure stage. The research results can help to determine the development type and stage of bank slope toppling deformation in V-shaped Gorge area, so as to predict its further development deformation characteristics.

Abstract Glutamate, the major excitatory neurotransmitter in the central nervous system, has also been found to play a role in embryonic stem (ES) cells. However, the exact mechanism and function of glutamatergic signaling in ES cells remain poorly understood. In this study, we identified a glutamatergic transmission circuit in ES cells that operates through an autocrine mechanism and regulates cell proliferation. We performed biological analyses to identify the key components involved in glutamate biosynthesis, packaging for secretion, reaction, and reuptake in ES cells, including glutaminase, vesicular glutamate transporter, glutamate N-methyl-d-aspartate (NMDA) receptor, and cell membrane excitatory amino-acid transporter (EAAT). We directly quantified the released glutamate signal using microdialysis-high performance liquid chromatography-tandem mass spectrometry (MD–HPLC–MS–MS). Pharmacological inhibition of endogenous glutamate release and the resulting tonic activation of NMDA receptors significantly affected ES cell proliferation, suggesting that ES cells establish a glutamatergic autocrine niche via releasing and responding to the transmitter for their own regulation.

Underground coal gasification (UCG) is an efficient method for the conversion of deep coal resources into energy. The scope of this work is to model the subsidence of four gasification cavities with a size of 30 m × 30 m × 15 m, separated by 15 m wide pillars. Two scenarios of gasification sequence are modelled, one with the gasification of cavities 1 and 2 followed by 3 and 4, and the other one with the sequence of cavities 1 and 3, followed by 2 and 4. The results show that the final surface subsidence after gasification of four cavities is 9.8 mm and the gasification sequence has an impact only on the subsidence at the intermediate stage but has no impact on the final subsidence after all four cavities are formed, when only the elasticity regime is considered. Additionally, the maximum surface subsidence for the studied cavities of different sizes ranges from 0.016 mm to 7.14 mm, and the relationship between the subsidence and the cavity volume is approximately linear. Finally, a prediction model of surface subsidence deformation is built up using the elastic plate theory, and the formula of surface deformation at a random point is given. The maximum difference between measured and calculated deformation is 4.6%, demonstrating that the proposed method can be used to predict the ground subsidence induced by UCG.

ABSTRACT Pseudorabies virus (PRV) is the causative pathogen of Aujeszky’s disease. It causes high mortality and miscarriage rates in the infected swine, leading to tremendous economic losses in the global swine industry. PRV has also been demonstrated to trigger viral encephalitis in humans. The eradication policy and large-scale vaccination have been adopted globally as the most effective strategy against PRV. A simple, fast, and sensitive diagnostic method is highly demanded to differentiate between vaccinated and infected swine. Herein, we designed a detection system combining multienzyme isothermal rapid amplification (MIRA) and CRISPR-Cas12a (termed MIRA-Cas12a), characterized by high sensitivity and specificity, low cost, less equipment, and convenient visualization. By targeting the gB, gE, and TK genes of PRV, the MIRA-Cas12a assay is able to distinguish the infected, uninfected, and vaccinated swine by the naked eyes in 40 min (from DNA extraction to result readout) and with comparable sensitivity to conventional quantitative PCR. A 37°C heater and a source of blue light are all the equipment required to detect PRV. Thus, the MIRA-Cas12a detection will facilitate PRV surveillance and minimize the financial losses to the swine industry. IMPORTANCE Pseudorabies virus (PRV) causes high mortality and miscarriage rates in the infected swine, and the eradication policy coupled with large-scale vaccination of live attenuated vaccines has been adopted globally against PRV. Differential diagnosis of the vaccinated and infected swine is highly demanded. Our multienzyme isothermal rapid amplification (MIRA)-Cas12a detection method described in this study can diagnose PRV with a superior sensitivity comparable to the quantitative PCR (qPCR) and a competitive detection speed (only half the time as qPCR needs). The portable feature and the simple procedure of MIRA-Cas12a make it easier to deploy for clinical diagnosis, even in resource-limited settings. The MIRA-Cas12a method would provide immediate and accurate diagnostic information for policymakers to respond promptly.

Objective Olecranon osteotomy and paratricipital approaches were widely used in the treatment of type C distal humerus fracture but some disadvantages exist, so a combined medial and lateral approach was designed. The objective of this study was to investigate and compare the clinical outcomes of combined medial and lateral approach with the paratricipital approach in open reduction and internal fixation of type C distal humerus fractures. Methods From May 2018 to April 2020, 37 patients with type C distal humerus fracture who accepted open reduction and internal fixation in our hospital were enrolled in this study. All cases were randomly divided into two groups according to the surgical approach: combined medial and lateral approach group (19 cases), paratricipital approach group (18 cases). All of the patients received open reduction and double vertical plates fixation. The operation and follow‐up indexes, including operation time, blood loss, incision length, triceps muscle strength, flexion‐extension arc of elbow and forearm rotation arc, were recorded and compared. Caja score was used to assess the quality of fractures reduction. Mayo Elbow Performance Score (MEPS) was used to evaluate the elbow function in the follow‐up. Complications such as incision infection, ulnar nerve injury, degenerative osteoarthritis, and heterotopic ossification were analyzed. Results The differences in age, gender, and AO classification of fractures between two groups were not statistically significant (p > 0.05). The sum of medial and lateral incision length of combined approach group was longer than the midline incision of paratricipital approach group (15.4 ± 0.8 vs. 14.6 ± 0.8, p 0.05), blood loss (71.3 ± 24.5 vs. 72.8 ± 24.6, p > 0.05), and Caja score (16.05 ± 5.67 vs. 15.56 ± 5.66, p > 0.05). During the follow‐up, the MEPS of combined approach group was higher than that of paratricipital approach group at 3 months postoperatively (80.5 ± 5.7 vs. 68.9 ± 8.1, p 0.05) and at the last follow‐up (86.8 ± 7.1 vs. 86.9 ± 7.7, p > 0.05) between the two groups. There was no significant difference in triceps muscle strength (p > 0.05), flexion‐extension arc (126.8 ± 5.3 vs. 128.9 ± 6.0, p > 0.05), and forearm rotation arc (163.2 ± 5.3 vs. 163.6 ± 4.8, p > 0.05) at the last follow‐up. Although the incidence of complication of combined approach group (15.8%) was lower than that of paratricipital approach group (22.2%), the difference was not statistically significant (p > 0.05). Conclusions The combined medial and lateral approach was an effective and safe way of open reduction and internal fixation for type C distal humerus fractures. Compared with the paratricipital approach, the combined medial and lateral approach could restore the elbow function more quickly postoperatively, and the long‐term results were comparable.

Air-borne pollutants in particulate matter (PM) form, produced either physically during industrial processes or certain biological routes, have posed a great threat to human health. Particularly during the current COVID-19 pandemic, effective filtration of the virus is an urgent matter worldwide. In this review, we first introduce some fundamentals about PM, including its source and classification, filtration mechanisms, and evaluation parameters. Advanced filtration materials and their functions are then summarized, among which polymers and MOFs are discussed in detail together with their antibacterial performance. The discussion on the application is divided into end-of-pipe treatment and source control. Finally, we conclude this review with our prospective view on future research in this area.

ABSTRACT Mobile genetic elements (MGEs) or mobilomes promote the mobilization and dissemination of antimicrobial resistance genes (ARGs), serving as critical drivers for antimicrobial resistance (AMR) accumulation, interaction, and persistence. However, systematic and quantitative evaluations of the role of mobilome in spreading resistome in a bacterial pathogen remain unaddressed, partially due to the lack of closed genomes. Here, we examined MGEs across 1,817 Salmonella isolates with complete genomic sequences from 58 countries between 1911 and 2022. We found the plasmid harboring 69.8% ARGs to be the largest ARG reservoir, correlated with serovar-based evolution in most Salmonella lineages. Prophages, specifically RCS47 and SJ46, play a crucial role in the plasmids’ plasticity and the acquisition of ARGs. Furthermore, distinct ARG accumulation, including resistance toward last-resort antibiotics, exhibited an MGE-favored manner. Certain socioeconomic and ecological factors, as additional layers of mediators, are associated with the preferential distribution of MGE-mediated ARGs in Salmonella. Collectively, this study demonstrated an uncharted knowledge of the segmentation of Salmonella resistome driven by mobilome, elucidating dynamic drivers and distinct mediators for resistome development that are of immediate relevance for targeted interventions.IMPORTANCEAntimicrobial resistance (AMR) has become a significant global challenge, with an estimated 10 million deaths annually by 2050. The emergence of AMR is mainly attributed to mobile genetic elements (MGEs or mobilomes), which accelerate wide dissemination among pathogens. The interaction between mobilomes and AMR genes (or resistomes) in Salmonella, a primary cause of diarrheal diseases that results in over 90 million cases annually, remains poorly understood. The available fragmented or incomplete genomes remain a significant limitation in investigating the relationship between AMR and MGEs. Here, we collected the most extensive closed Salmonella genomes (n = 1,817) from various sources across 58 countries. Notably, our results demonstrate that resistome transmission between Salmonella lineages follows a specific pattern of MGEs and is influenced by external drivers, including certain socioeconomic factors. Therefore, targeted interventions are urgently needed to mitigate the catastrophic consequences of Salmonella AMR.

ABSTRACT Typhoid fever, caused by Salmonella Typhi (S. Typhi), is a life-threatening disease, usually food-borne and commonly associated with international travel. The disease transmission remains endemic in many low- and middle-income countries, representing further hotspots for seeding new global outbreaks. China has historically been affected by typhoid fever, but the respective roles of local transmission and importation remain unknown. Here, we generated a nationwide map of the typhoid burden in China and investigated the associations between typhoid disease, climate and various socioeconomic parameters. To assess transmission dynamics, we sub-sampled S. Typhi isolated within China over five decades and sequenced their genomes. The resulting 705 new genomes, placed in context with 5,190 global isolates from 87 countries on six continents, led to the discovery of several predominant inland Chinese clones belonging to the clades 2.1/2.3/3.2/4.3. These clones were associated with multiple introductions from overseas, followed by local expansion. Notably, 4.3.1 isolates from eastern China were not genetically close to those from northwestern China but to the international isolates, indicating their association with international travel. Additional in vitro assays showed that 4.3.1 elaborated better intracellular survival, acid tolerance, and desiccation tolerance than other lineages, partially explaining its success. For the first time, we have probed typhoid transmission in China, finding local transmission and importation, which could guide the policy for typhoid control. IMPORTANCE Typhoid fever is a life-threatening disease caused by Salmonella enterica serovar Typhi, resulting in a significant disease burden across developing countries. Historically, China was very much close to the global epicenter of typhoid, but the role of typhoid transmission within China and among epicenter remains overlooked in previous investigations. By using newly produced genomics on a national scale, we clarify the complex local and global transmission history of such a notorious disease agent in China spanning the most recent five decades, which largely undermines the global public health network.

Abstract Background Most Non‐small cell lung cancer (NSCLC) patients tend to have metastases at the initial diagnosis. However, limited knowledge has been established regarding which factors, are associated with its metastases. This study aims to identify more biomarkers associated with its organ tropism metastasis and to establish models for prediction of its metastatic organs. Methods We performed targeted next‐generation sequencing (NGS) to detect genes related to lung cancer in 272 patients with primary advanced NSCLC from Northeast China. We adopted Fisher test, multivariate logistic regression analysis to identify metastasis‐related gene mutations and to establish prediction models. Results Mutations of EGFR (p = 0.0003, OR = 2.554) (especially EGFR L858R [p = 0.02, OR = 2.009]), ATM (p = 0.008, OR = 11.032), and JAK2 (p = 0.009, OR = Inf) were positively and of TP53 exon4mut (p = 0.001, OR = 0.173) was negatively correlated with lung metastasis, and those of CSF1R (p = 0.01, OR = Inf), KIT (p = 0.03, OR = 4.746), MYC (p = 0.05, OR = 7.938), and ERBB2 (p = 0.02, OR = 2.666) were positively correlated with pleural dissemination; those of TP53 (p = 0.01, OR = 0.417) was negatively, while of SMAD4 (p = 0.03, OR = 4.957) was positively correlated with brain metastasis of NSCLC. Additionally, smoking history (p = 0.004, OR = 0.004) was negatively correlated with pleural dissemination of NSCLC. Furthermore, models for prediction of lung metastasis (AUC = 0.706), pleural dissemination (AUC = 0.651), and brane metastasis (AUC = 0.629) were established. Conclusion Taken together, this study revealed nine mutant genes and smoking history associated with organ tropism metastases of NSCLC and provided three models for the prediction of metastatic organs. This study enables us to predict the organs to which non‐small cell lung cancer metastasizes before it does develop.

Remote sensing images (RSIs) contain important information, such as airports, ports, and ships. By extracting RSI features and learning the mapping relationship between image features and text semantic features, the interpretation and description of RSI content can be realized, which has a wide range of application value in military and civil fields, such as national defense security, land monitoring, urban planning, and disaster mitigation. Aiming at the complex background of RSIs and the lack of interpretability of existing target detection models, and the problems in feature extraction between different network structures, different layers, and the accuracy of target classification, we propose an object detection and interpretation model based on gradient-weighted class activation mapping and reinforcement learning. First, ResNet is used as the main backbone network to extract the features of RSIs and generate feature graphs. Then, we add the global average pooling layer to obtain the corresponding feature weight vector of the feature graph. The weighted vectors are superimposed to output class activation maps. The reinforcement learning method is used to optimize the generated region generation network. At the same time, we improve the reward function of reinforcement learning to improve the effectiveness of the region generation network. Finally, network dissecting analysis is used to obtain the interpretable semantic concept in the model. Through experiments, the average accuracy is more than 85%. Experimental results in the public RSI description dataset show that the proposed method has high detection accuracy and good description performance for RSIs in complex environments.

To further enhance the security of image encryption, a new chaos-based image encryption algorithm (IEA) based on discrete Fourier transform and Joseph traversal is proposed to encrypt the plain image in both the frequency domain and space domain simultaneously. In the proposed IEA, the logistic map is used to generate the appropriate chaotic sequence, and the improved Joseph traversal is used to scramble the image in different starting positions and variable step sizes. Then, block diffusion is performed at the end. The main finding concerning the proposed IEA is that the combination of discrete Fourier transform and Joseph traversal can enhance the security of the image information, which has been validated by measuring the performance in resisting the common types of attacks.

The extensive usage of fossil fuels has caused significant environmental pollution, climate change and energy crises. The significant advantages of hydrogen, such as cleanliness, high efficiency, and a wide range of sources, make it quite promising. Hydrogen is prone to material damage, which may lead to leakage. High-pressure leaking hydrogen is highly susceptible to spontaneous combustion due to its combustion characteristics, which may cause jet fire or explosion accidents, resulting in serious casualties and property damage. This paper presents a detailed review of the research progress on hydrogen leak diffusion characteristics, leak spontaneous combustion mechanisms and material hydrogen damage mechanisms from the perspectives of theoretical analysis, experiments and numerical simulations. This review points out that although a large number of research results have been obtained on the safety characteristics of hydrogen, there are still some deficiencies and limitations. Further research topics are clarified, such as further optimizing the kinetic mechanism of the high-pressure hydrogen leakage reaction and turbulence model, exploring the expansion and dilution law of hydrogen clouds after liquid hydrogen flooding, further studying the spontaneous combustion mechanism of leaked hydrogen and the interaction between mechanisms, and investigating the synergistic damage effect of hydrogen and other components on materials. The leakage spontaneous combustion process in open space, the development process of the bidirectional effect of hydrogen jet fuel and crack growth under the impact of high-pressure hydrogen jet fuel on the material may need to be explored next.

As a high-efficiency hydrogen energy carrier, ammonia has the significant advantages such as high energy density, low storage and transportation cost, high safety and carbon-free energy storage. It can effectively solve the problems of high-pressure storage and transportation of hydrogen energy, which is of great significance to open up a featured storage and transportation roadmap for hydrogen energy correponding to the characteristics of energy structure in China and achieve the goals of carbon peaking and carbon neutrality. Based on the fact that ammonia is easier to store and transport than hydrogen, the development status of ammonia-hydrogen green energy roadmap and the research progress of the transportation process system, safety technology and design standard of liquid ammonia pipeline relying on the roadmap were reviewed. In view of the problems that the safe pipeline transportation technology of liquid ammonia needs further research and the design experience of liquid ammonia pipeline is immature in China, the following 4 suggestions were proposed: (1) Studies should be conducted on the basic physical properties of liquid ammonia containing impurities and the phase change characteristics, as well as the thermo-hydraulic behaviors, of different pipeline transportation technologies through the combination of experiments and simulation methods. (2) The mature experience of oil and gas pipelines can be referred to liquid ammonia pipelines, but comprehensive fitness-for-service evaluation should be performed before transferring in-service oil and gas pipelines to liquid ammonia transportation ones, if any. (3) The leakage monitoring system should be improved based on the leakage and diffusion characteristics of liquid ammonia pipeline, and the effect of protection technologies should be verified and optimized. (4) The construction, operation and management standards of liquid ammonia pipelines should be improved from the perspectives of pipeline materials, equipment, safety and corrosion prevention, etc.

Proteoglycans (PGs), also known as a viscous lubricant, is the main component of the cartilage extracellular matrix (ECM). The loss of PGs is accompanied by the chronic degeneration of cartilage tissue, which is an irreversible degeneration process that eventually develops into osteoarthritis (OA). Unfortunately, there is still no substitute for PGs in clinical treatments. Herein, we propose a new PGs analogue. The Glycopolypeptide hydrogels in the experimental groups with different concentrations were prepared by Schiff base reaction (Gel-1, Gel-2, Gel-3, Gel-4, Gel-5 and Gel-6). They have good biocompatibility and adjustable enzyme-triggered degradability. The hydrogels have a loose and porous structure suitable for the proliferation, adhesion, and migration of chondrocytes, good anti-swelling, and reduce the reactive oxygen species (ROS) in chondrocytes. In vitro experiments confirmed that the glycopolypeptide hydrogels significantly promoted ECM deposition and up-regulated the expression of cartilage-specific genes, such as type-II collagen, aggrecan, and glycosaminoglycans (sGAG). In vivo, the New Zealand rabbit knee articular cartilage defect model was established and the hydrogels were implanted to repair it, the results showed good cartilage regeneration potential. It is worth noting that the Gel-3 group, with a pore size of 122 ​± ​12 ​μm, was particularly prominent in the above experiments, and provides a theoretical reference for the design of cartilage-tissue regeneration materials in the future.

To investigate the toppling displacement evolution characteristics of anti-dip rock slopes, the Xiaodongcao-Zhengjiadagou bank slope is taken as an engineering case, and firstly, the geological geometric distribution characteristics of the slope are obtained by superimposing the lithology, slope, and elevation raster layers of the slope through ArcGIS, and the geological partition with the largest area is the Lower Triassic Daye Formation, bottom elevation, and medium slope; based on the actual surface displacement monitoring data, the spatio-temporal evolution nephogram of toppling displacement of bank slope every half year is interpolated by Inverse Distance Weight method, and then the last displacement nephogram is assigned to the thousandth and superimposed with the geological geometric partition to obtain the displacement superposition characteristics. The results show that: the obvious zone of horizontal displacement deformation mainly occurs in the front and middle of the bank slope, mainly shear deformation, vertical displacement is primarily in the front and the back edge of the bank slope and the total displacement deformation is more similar to the horizontal displacement; the horizontal displacement value is larger than the vertical displacement value, the horizontal displacement deformation controls the overall deformation of the bank slope; through the analysis of the geometric superposition evolution of the anti-dip rock slope, the displacement superposition strong deformation zone is located at the boundary between the Triassic Jialingjiang Formation (T1j) and the Triassic Daye Formation (T1d).

The wax deposits of diesel may be formed at low environment temperature during the batch transportation of products pipeline, which will contaminate the subsequent gasoline, resulting in the loss of oil mixing. Therefore, researches on wax deposition of diesel are significant to ensure the economic and efficient operation of products pipelines. Herein, the existing theories on wax deposition were reviewed, and the status of experimental study on wax deposition of diesel was clarified from perspectives of static and dynamic experiments. In addition, the prediction models of wax deposition rate of diesel based on the theories of molecular diffusion and shear dispersion were summarized. Thereby, it is pointed out that strengthening the research on wax deposition mechanism, establishing wax deposition model, and quantitatively characterizing the change rules of quality parameters of the subsequent gasoline with the wax dissolved, are the key direction of research on batch transportation of products pipeline. Besides, by systematically representing the progress of researches on wax deposition of diesel, some reference is provided for the relevant deep researches that may be performed in the future.

Abstract Streptococcus suis has been well-recognized as a zoonotic pathogen worldwide, and the diversity and unpredictable adaptive potential of sporadic human strains represent a great risk to the public health. In this study, S. suis LSM178, isolated from a patient in contact with pigs and raw pork, was assessed as a hyper-virulent strain and interpreted for the virulence based on its genetic information. The strain was more invasive for Caco-2 cells than two other S. suis strains, SC19 and P1/7. Sequence analysis designated LSM178 with serotype 2 and a novel sequence type 1005. Phylogenetic analysis showed that LSM178 clustered with highly virulent strains including all human strains and epidemic strains. Compared with other strains, these S. suis have the most and the same virulent factors and a type I-89 K pathogenicity island. Further, groups of genes were identified to distinguish these highly virulent strains from other generally virulent strains, emphasizing the key roles of genes modeling transcription, cell barrier, replication, recombination and repair on virulence regulation. Additionally, LSM178 contains a novel prophage conducive potentially to pathogenicity.

In the process of hydrogen storage and transportation, if the high-pressure hydrogen in the storage tanks is released suddenly into the downstream pipelines, spontaneous ignition may occur, which can result in jet fire or explosion accidents. The obstacles such as the valves and welding slags inside the pipelines may affect the process and mechanism of spontaneous ignition of the leaked hydrogen. Therefore, a Computational Fluid Dynamics (CFD) model for the spontaneous ignition as a result of the high-pressure hydrogen leakage was developed and its reliability was validated by the experimental data. Subsequently, simulation analysis was performed for the spontaneous ignition process resulted from the high-pressure hydrogen leakage under the effect of obstacles at different locations in the pipelines. The results show that, the presence of obstacles has a significant influence on the shock wave propagation process in the pipelines, the variation of shock waves shows sensitivity to the obstacles, and the presence of obstacles in the pipelines will promote the flame propagation. In addition, the presence of obstacles increases the possibility of hydrogen spontaneous ignition in the pipelines, and the reflected shock waves generated by the obstacles will significantly change the spontaneous ignition mechanism of hydrogen. Generally, the research results could provide useful references for the design and safe operation of hydrogen pipelines.

BackgroundWith the widespread use of next-generation sequencing (NGS) in clinical practice, an increasing number of biomarkers that predict a response to anti-tumor therapy in non-small cell lung cancer (NSCLC) has been identified. However, validated biomarkers that can be used to detect a response to platinum-based chemotherapy remain unavailable. Several studies have suggested that homologous recombination deficiency (HRD) may occur in response to platinum-based chemotherapy in ovarian cancer and breast cancer. However, currently there is a lack of proven and reliable HRD markers that can be used to screen for patients who may benefit from platinum-based chemotherapy, especially in NSCLC.MethodsNGS was used to screen for gene mutations, including homologous recombination (HR) genes and common driver gene mutations in NSCLC. Cox regression analysis was performed to identify potential clinicopathological or gene mutation factors associated with survival in patients receiving platinum-based chemotherapy, while Kaplan–Meier analysis with the log-rank test was performed to assess the effect of HR gene mutations on progression-free survival (PFS).ResultsIn a retrospective cohort of 129 patients with advanced NSCLC, 54 who received platinum-based chemotherapy with or without anti-angiogenic therapy were included in the analysis. Univariate and multivariate Cox proportional hazard regression analyses showed that HR gene mutations were associated with platinum-based chemotherapy sensitivity. Efficacy results indicated that the objective response rates (ORR) for patients with BRCA1/2 mutations and BRCA1/2 wild type were 75% and 30.4% (p=0.041), while the median PFS was 7.5 and 5.5 months (hazard ratio [HR], 0.52; 95% CI, 0.27–1.00; p=0.084), respectively. The ORRs of patients with HR gene mutations and HR gene wild type were 60% and 23.6% (p=0.01), and the median PFS was 7.5 and 5.2 months (HR, 0.56; 95% CI, 0.32–0.97; p=0.033), respectively.ConclusionsHR gene mutations show potential as promising biomarkers that may predict sensitivity to platinum-based chemotherapy in advanced and metastatic NSCLC.

Abstract Invasive nontyphoidal Salmonella (iNTS) causes extraintestinal infections with ~15% case fatality in many countries. However, the mechanism by which iNTS emerged in China remains unaddressed. We conducted clinical investigations of iNTS infection with recurrent treatment failure, caused by underreported Salmonella enterica serovar Livingstone (SL). Genomic epidemiology demonstrated five clades in the SL population and suggested that the international animal feed trade was a likely vehicle for their introduction into China, as evidenced by multiple independent transmission incidents. Importantly, isolates from Clade‐5‐I‐a/b, predominant in China, showed an invasive nature in mice, chicken and zebrafish infection models. The antimicrobial susceptibility testing revealed most isolates (> 96%) in China are multidrug‐resistant (MDR). Overall, we offer exploiting genomics in uncovering international transmission led by the animal feed trade and highlight an emerging hypervirulent clade with increased resistance to frontline antibiotics.

Objective To investigate the factors, surgical treatment methods and clinical effect of internal fixation failure of intertrochanteric and subtrochanteric fractures. Methods From June 2015 to May 2019, arthroplasty and internal fixation revision were used to treat 18 cases of internal fixation failure of intertrochanteric and subtrochanteric fractures. There were 10 males and eight females, with an average age of 67.3 years (38–92 years). The 16 cases of initial intertrochanteric fractures were classified according to AO/OTA:13 cases of A2 and 3 cases of A3, the other 2 cases were subtrochanteric fractures (Seinsheimer type IV). The internal fixation failure was treated with total hip arthroplasty (6 cases), bipolar hemiarthroplasty (4 cases), revision with proximal femoral lockingplate (4 cases) and extend intramedullary nail (4 cases). Results All patients were followed up for an average of 24.7 months (range, 12 to 36 months). The average operative time was 111.4 min (range, 72 to 146 min) and the average intraoperative blood loss was 403.6 mL (range, 200 to 650 mL). The average time of fracture union was 6.9 months (range, 5 to 9 months) for cases of internal fixation revision. The operative time of the arthroplasty group was shorter than the revision group (P

The current technological world is growing rapidly and each aspect of life is being transformed toward automation for human comfort and reliability. With autonomous vehicle technology, the communication gap between the driver and the traditional vehicle is being reduced through multiple technologies and methods. In this regard, state-of-the-art methods have proposed several approaches for advanced driver assistance systems (ADAS) to meet the requirement of a level-5 autonomous vehicle. Consequently, this work explores the role of textual cues present in the outer environment for finding the desired locations and assisting the driver where to stop. Firstly, the driver inputs the keywords of the desired location to assist the proposed system. Secondly, the system will start sensing the textual cues present in the outer environment through natural language processing techniques. Thirdly, the system keeps matching the similar keywords input by the driver and the outer environment using similarity learning. Whenever the system finds a location having any similar keyword in the outer environment, the system informs the driver, slows down, and applies the brake to stop. The experimental results on four benchmark datasets show the efficiency and accuracy of the proposed system for finding the desired locations by sensing textual cues in autonomous vehicles.

We, the Publisher, have retracted the following article: Yin Lyu, Lin Teng (2022). Parallax information fusion-based for dance moving image posture extraction. EAI Endorsed Scal Inf Syst. http://dx.doi.org/10.4108/eai.16-12-2021.172437 The authors submitted the article to the Special Issue on “Real-time image information processing with deep neural networks and data mining technologies”, edited by the Guest Editors Dr Prof. Hang Li (Northeastern University, China) and Dr Prof. Jochen Schiewe, HafenCity Universität Hamburg, Germany. From our Research Integrity Team, we performed auditing of the editorial process of this Special Issue, and we identified misconduct during the review process. The generated reviews were simple, generalistic, without rigour, and the same for every submission. Following the COPE guidelines, we decided to RETRACT this article because “Peer review manipulation suspected after publication”. We informed the authors about this decision. The retracted article will remain, and it has been watermarked as “RETRACTED”.

We, the Publisher, have retracted the following article: Dianhuai Shen, Xueying Jiang, Lin Teng (2022). A novel Gauss-Laplace operator based on multi-scale convolution for dance motion image enhancement. EAI Endorsed Scal Inf Syst. http://dx.doi.org/10.4108/eai.17-12-2021.172439 The authors submitted the article to the Special Issue on “Real-time image information processing with deep neural networks and data mining technologies”, edited by the Guest Editors Dr Prof. Hang Li (Northeastern University, China) and Dr Prof. Jochen Schiewe, HafenCity Universität Hamburg, Germany. From our Research Integrity Team, we performed auditing of the editorial process of this Special Issue, and we identified misconduct during the review process. The generated reviews were simple, generalistic, without rigour, and the same for every submission. Following the COPE guidelines, we decided to RETRACT this article because “Peer review manipulation suspected after publication”. We informed the authors about this decision. The retracted article will remain, and it has been watermarked as “RETRACTED”.

Objective To investigate the surgical approach, fixation, and clinical effect of comminuted coronal shear fracture of distal humerus. Methods From March 2017 to February 2019, we had used open reduction and internal fixation to treat 19 cases of comminuted distal humeral coronal shear fracture. There were 8 males and 11 females, with an average age of 44.6 years (19–72 years). There were 10 cases on left side and 9 cases on right side. All cases were closed fractures. According to Dubberley's classification, there were six cases of type 1, six cases of type 2, and seven cases of type 3. The lateral Kocher approach, extended Kocher approach, extended Kocher approach combined with a medial incision and the olecranon osteotomy approach were used for exposure. Headless screw, Kirschner wire, and suture were used to fix the fractures. Two cases were fixed with hinged elbow fixators additionally. The follow‐up was evaluated by Mayo Elbow Performance Score (MEPS). Results All patients were followed up for an average of 17.1 months (range, 12 to 30 months). The average time of fracture union was 8.8 ± 1.9 weeks. There were three cases of degenerative osteoarthritis of elbow and one case of heterotopic ossification after operation. A total of 10 patients underwent removal of implants. At the last follow‐up, the elbow flexion‐extension arc was 130.5° ± 10.5°. The forearm rotation arc was 167.4° ± 6.1°. The MEPS was 85.8 ± 8.5, the results were classified as excellent in nine cases, good in eight, and fair in two. The excellent and good rate was 89.5%. The time of fracture union of type 1 was shorter than type 3 (P = 0.024), the elbow flexion‐ extension arc of type 1 fracture was better than type 2 (P = 0.043) and type 3 (P = 0.012), the forearm rotation arc of type 1 fracture was better than type 3 (P = 0.006), the MEPS of type 1 fracture was better than type 2 (P = 0.009) and type 3 (P = 0.002). Conclusion Open reduction and internal fixation with headless screw, Kirschner wire, and suture can be used for the treatment of comminuted distal humeral coronal shear fractures. The elbow joint function can be restored satisfactorily.

The existence of back pressure at outlet has a direct impact on the separation performance of the separation separator. However, the influence of back pressure is not understood well due to the complicated interaction of the supersonic flow, condensation and shock waves. In this study, the condensation flow models of water vapor were established, the influence of back pressure on supersonic condensation properties of water vapor was investigated. The results show that when the back pressure exists, the position of the shock wave is more forward than that without condensation, and the strength of shock wave is weaker. The nucleation rate is generated around the position of x = 115 mm and increases sharply from 0 to 1025 m−3 s−1. The shock wave is generated at x = 145 mm and x = 122 mm when the outlet back pressure is 20 kPa and 30 kPa, respectively. The condensed droplets evaporate again with the effect of shock wave, and then the secondary condensation of droplets occurs owing to the cooling effect of nozzle. When the back pressure is higher than a certain value, the refrigeration environment in the nozzle is completely destroyed with the effect of shock wave, and the condensed droplets evaporate again.

Typhoid fever is a life-threatening disease caused by Salmonella enterica serovar Typhi (S. Typhi) and remains a significant public health burden in developing countries. In China, typhoid fever is endemic with a limited number of reported outbreaks. Recently, Chinese local Center for Disease Prevention and Control is starting to apply whole genome sequencing for tracking the source of outbreak isolates. In this study, we conducted a retrospective investigation into a community outbreak of typhoid fever in Lanling, China, in 2016. A total of 26 S. Typhi isolates were recovered from the drinking water (n = 1) and patients' blood (n = 24) and stool (n = 1). Phylogenetic analysis indicated the persistence of the outbreak isolates in drinking water for more than 3 months. The genomic comparison demonstrated a high similarity between the isolate from water and isolates from patients in their genomic content, virulence gene profiles, and antimicrobial resistance gene profile, indicating the S. Typhi isolate from drinking water was responsible for the examined outbreak. The result of pulsed-field gel electrophoresis (PFGE) revealed these isolates had identical PFGE pattern, indicating they are clonal variants. Additionally, phylogeographical analysis of global S. Typhi isolates suggested the outbreak isolates are evolutionarily linked to the isolates from the United Kingdom and Vietnam. Taken together, this study highlights the drinking water and international travel as critical control points of mitigating the outbreak, emphasizing the necessity of regular monitoring of this pathogen in China.

The present study used PFC numerical software to examine the mechanical properties and fracture propagation characteristics of the fractured rock mass under coupling of heavy rainfall infiltration and mining unloading. Based on the engineering background of the Dexing mine, the pore water pressure is set to 0, 0.5, 1.0, 1.5, and 2.0 mpa, the true triaxial lateral unloading rate is 0.3 mpa/level and 0.6 mpa/level, and the water content state of rock is dry, natural, and saturated. Then, the true triaxial compression numerical simulation test is carried out, and the results showed that with the increase of the water content, the rock compaction stage increases, the elastic stage shortens, and the yield stage becomes more obvious. The faster the unloading rate is, the greater the influence on the rock strain is. After unloading, the stress jump point appears and the strain increase rate becomes larger, the volume of the rock increases and occurs as large s in the unloading direction, and finally it leads to severe brittle failure of the rock. With the increase of rock pore water pressure, the compressive strength and the peak strain of the rock decrease, and the pore water pressure accelerates the process of rock failure.

A novel five-dimensional (5D) memristor-based symmetric circuit, which consists of two symmetric capacitors, two symmetric inductors and only one memristor is presented in this article. The multivariable first order and multivariable second order polynomial functions are used for the internal state function of the memristor respectively. Theoretical and simulation analyses of the novel memristive circuit are investigated using equilibrium points, phase portraits, bifurcation diagrams and Lyapunov exponent spectra, etc. Complex chaotic behaviors are observed and analyzed through simulation results. The first order internal state function memristor-based symmetric circuit system can only exhibit chaotic behavior whereas the second order internal state function memristor-based symmetric circuit system can generate not only chaotic attractors, but also hyperchaotic attractors in proper parameters.

This article has been retracted, and the retraction notice can be found here: http://dx.doi.org/10.4108/eai.8-4-2022.173797. Traditional image enhancement methods have the problems of low contrast and fuzzy details. Therefore, we propose a novel Gauss-Laplace operator based on multi-scale convolution for dance motion image enhancement. Firstly, multi-scale convolution is used to preprocess the image. Then, we improve the traditional Laplace edge detection operator and combine it with Gauss filter. The Gaussian filter is used to smooth the image and suppress the noise, and the edge detection is processed based on the Laplace gradient edge detector. The detail image extracted by Gauss-Laplace operator and the image with brightness enhancement are linearly weighted fused to reconstruct the image with clear detail edge and strong contrast. Experiments are carried out with detailed images in different scenes. It is compared with traditional methods to verify the effectiveness of the proposed method.

We, the Publisher, have retracted the following article: Yin Lyu, Lin Teng (2022). Parallax information fusion-based for dance moving image posture extraction. EAI Endorsed Scal Inf Syst. http://dx.doi.org/10.4108/eai.8-4-2022.173799 The existing motion image posture contour extraction results have low definition and serious detail loss. To solve this problem, we propose a novel dance moving image posture extraction method based on parallax information fusion. Firstly, the image with motion information is statistically analyzed by using the information fusion process to determine the position of the motion region. After the noise is reduced by morphological processing, the initial motion posture profile is obtained. The parallax between different control points and the center is used as the active contour model to shape the contraction force and expansion force, which can effectively assist the initial edge contour curve to gradually approach the real edge contour. Finally, the contour of the current moving image is extracted from the sequence image contour to obtain the attitude contour of the moving image. The experimental results show that the proposed method can extract the contour of the moving image clearly with less detail loss, which proves that the proposed method has strong practical performance and can effectively find the contour of the moving object.

Supercritical CO2 pipelines usually are used to link the CO2 capture system to the geological storage. There are severe hazards once the asphyxiating gas leaks from the long-distance pipeline. The uncertainty of near-field jet characteristics results in imprecise consequences assessment of accidental release of supercritical CO2. To improve the prediction of consequences of accidental release accuracy, the near-field mechanisms of flashing-spray jet was investigated. In this work, an experimental setup with multiple measurement instruments was developed to impose controllable CO2 release from a high-pressure vessel. The flashing-spray jet structures of supercritical CO2 from circular and rectangular orifices were recorded by a high-speed camera. Results indicate that the near-field structures of supercritical CO2 jet from circular and rectangular orifices are totally different, which causes the different dispersion consequences. The jet angle and shock waves were analyzed quantitatively. Lastly, the models of flashing-spray based on the two different phenomena from rectangular and circular orifices were discussed. The combination of macroscopic and microscopic data in the jet can help to understand the complex physics and improve discharge and dispersion model. This work provides a fundamental data to consequences assessment of accidental release of supercritical CO2.

Aiming at nonlinear flow in fractured porous media, based on the finite volume method, the discrete equations of Darcy flow in porous and Forchheimer flow in fracture were derived, and a solution method for coupling flow is proposed. The flow solution by the proposed method for single fracture and intersecting fracture is verified against Frih’s solution. Based on this method, nonlinear flow behavior for fractured rock deep-buried tunnels under high water heads was discussed. The results show that the hydraulic gradient of surrounding rock is characterized by “large at the bottom and small at the top”, with a maximum difference of 2.5 times. Therefore, the flow rate at the bottom of the tunnel is greater than that at the top. The fracture flow rate along the flow direction is also greater than that in the vertical flow direction, with a maximum difference of 60 times. The distribution homogeneity and density of fracture are the most important factors that affect the hydraulic behavior of fractured rock tunnels. The more fractures concentrated in the direction of water pressure and the greater the density, the greater the surrounding rock conductivity and the greater the flow rate of the tunnel. Under this condition, the water-inflow accident of the tunnel would be prone to occur. The research results provide a reference for the waterproof design and engineering practice of fractured rock tunnels.

The lack of hydrogen (H2) transportation infrastructure restricts the development of the H2 industry. Owing to the high investment of building specific facilities, using existing natural gas (NG) pipelines to transport a blend of H2 and NG (H2NG) is a viable means of transportation and approach for large-scale long-time storage. However, variation in the thermo-physical properties of an H2NG blend will impact the performance of pipeline appliances. To address the gaps in H2 transmission via an NG system in the context of energy consumption, in the present paper, a one-dimensional pipeline model is proposed to predict the blended flow in a real existing pipeline (Shan–Jing I, China). The data of NG components were derived from real gas fields. Furthermore, the influence of H2 fractions on pipeline energy coefficient and the layout of pressurization stations are comprehensively analyzed. In addition, the case of intermediate gas injection is investigated, and the effects of injection positions are studied. This study serves as a useful reference for the design of an H2NG pipeline system. The present study reveals that with the increasing in H2 fraction, the distance between pressure stations increases. Furthermore, when the arrangement of original pressure stations is maintained, overpressure occur. Intermediate gas injection results in the inlet pressure of subsequent pressurization stations reducing. Using existing pipeline network to transport H2NG, it is necessary to make appropriate adjustment.

The grain boundary (GB) plays a crucial role in dominating hydrogen-induced plastic deformation and intergranular failure in polycrystal metals. In the present study, molecular dynamics simulations were employed to study the effects of hydrogen segregation on dislocation plasticity of a series of symmetrical tilt grain boundaries (STGBs) with various hydrogen concentrations. Our study shows that hydrogen both enhances and reduces dislocation nucleation events from STGBs, depending on different GB structures. Specifically, for ⟨001⟩ STGBs, hydrogen does not affect the mode of heterogeneous dislocation nucleation (HDN), but facilitates nucleation events as a consequence of hydrogen disordering the GB structure. Conversely, hydrogen retards dislocation nucleation due to the fact that hydrogen segregation disrupts the transformation of boundary structure such as Σ9 (2 2 1¯) ⟨11¯0⟩ STGB. These results are helpful for deepening our understanding of GB-mediated hydrogen embrittlement (HE) mechanisms.

Mechanical pigging is a major wax removal technique in crude oil pipeline transportation. To lower the risk of pig stalling accidents in pigging, a superparamagnetic nanoparticle (SPM-NP) pigging system that consists of an electromagnetic pig and nanopaint is designed to soften the wax deposit and reduce the wax resistive force. During pigging, the induction coil on the pig generates an alternating magnetic field, which induces heat production of the nanopaint on the pipe wall. The COMSOL software is used to simulate the temperature distribution of the wax layer. Yield stress measurements reveal that the wax layer yield stress is nearly linearly correlated to temperature. Compared with a regular pig, the SPM-NP pigging system reduces the wax resistive force by up to 20~40%, with an acceptable electrical current intensity of about 20 A in the given cases. Multiple factors affecting the wax layer temperature were analyzed. SPM-NP heating could be a promising technique for wax remediation and hydrate prevention.

The tire pressure sensor is a wireless sensor that has been used in automobiles for many years, but the power supply has always been a bottleneck restricting the service life of the sensor. The article proposes a method for collecting heat energy in the environment, designs an energy harvesting circuit and achieves self-power supply of the tire pressure sensor. The thermoelectric generation(TEG) is used to convert the thermal energy accumulated inside the tire into electric energy. An ultra-low voltage electric energy collecting circuit is designed based on the LTC3108 power management chip. Experiments have shown that the designed circuit can collect energy as low as 100 mV, 10 mA, 1 mW, and successfully drive the tire pressure sensor after a period of accumulation.

As the continuous development of mobile social networks, the structure of the mobile social network increasingly becomes complex. It not only speeds up information transmission between people but also expands the scope of information exchange, which has become an essential and important social media in people's social life. How to effectively identify and classify these online communities has important practical significance for the study of social networks. Correctly detecting the community structure of mobile social networks can not only improve the accuracy of friend recommendation, link prediction, service user positioning, product marketing, and other aspects but also provide an important basis for the monitoring of online public opinion. But the traditional social network cluster method based on the trust degree mainly calculates the user trust by analyzing the interactive feedback information between users. This method cannot effectively solve the “cold start” problem in the trust calculation process, that is, for the new network node, the trust value of this node cannot be accurately measured due to the lack of interaction with other nodes. Focusing on this problem, we propose a Gaussian pigeon-oriented graph clustering algorithm for social networks' cluster in this paper. A graph model is first built. Then, an efficient K-medoid algorithm is utilized to search the user center in all groups. The Gaussian pigeon algorithm is used to search the similarity between each user and the central user. Users that meet the similarity threshold are divided into the same user group. Finally, the simulation results show that the proposed method has better cluster effect than other state-of-the-art social networks' clustering approaches.

Although hydrogen embrittlement (HE) behavior has been extensively studied in bulk materials, little is known about H-related deformation and the fracture of nanograined materials. In this study, H segregation and HE mechanisms of nanograined Fe with different grain sizes are unveiled, following the employment of classical molecular dynamics simulations. The H segregation ratio increased, but the local H concentration at the grain boundaries (GBs) decreased with decreases in the grain size at a given bulk H concentration. The results demonstrate that H atoms increased the yield stress of nanograined models irrespective of the grain size. Furthermore, it is revealed that brittle fractures were inhibited, and the resistance to HE increased as the grain size decreased, due to the fact that the small-grain models had a lower local H concentration at the GBs and an enhanced GB-mediated intergranular deformation. These results are a clear indication of the utility of grain refinement to resist H-induced brittle failure.

Salmonella is a group of bacteria that constitutes the leading cause of diarrheal diseases, posing a great disease burden worldwide. There are numerous pathways for zoonotic Salmonella transmission to humans; however, the role of companion animals in spreading these bacteria is largely underestimated in China. We aimed to investigate the prevalence of Salmonella in pet dogs and cats in Hangzhou, China, and characterize the antimicrobial resistance profile and genetic features of these pet-derived pathogens. In total, 137 fecal samples of pets were collected from an animal hospital in Hangzhou in 2018. The prevalence of Salmonella was 5.8% (8/137) in pets, with 9.3% (5/54) of cats and 3.6% (3/83) of dogs being Salmonella positive. By whole-genome sequencing (WGS), in silico serotyping, and multilocus sequence typing (MLST), 26 pet-derived Salmonella isolates were identified as Salmonella Dublin (ST10, n = 22) and Salmonella Typhimurium (ST19, n = 4). All of the isolates were identified as being multidrug-resistant (MDR), by conducting antimicrobial susceptibility testing under both aerobic and anaerobic conditions. The antibiotics of the most prevalent resistance were streptomycin (100%), cotrimoxazole (100%), tetracycline (96.20%), and ceftriaxone (92.30%). Versatile antimicrobial-resistant genes were identified, including floR (phenicol-resistant gene), blaCTX-M-15, and blaCTX-M-55 (extended-spectrum beta-lactamase genes). A total of 11 incompatible (Inc) plasmids were identified, with IncA/C2, IncFII(S), and IncX1 being the most predominant among Salmonella Dublin, and IncFIB(S), IncFII(S), IncI1, and IncQ1 being the most prevailing among Salmonella Typhimurium. Our study applied WGS to characterize pet-derived Salmonella in China, showing the presence of MDR Salmonella in pet dogs and cats with a high diversity of ARGs and plasmids. These data indicate a necessity for the regular surveillance of pet-derived pathogens to mitigate zoonotic diseases.

Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 is an enteric pathogen that causes life-threatening disease in humans, with cattle being major natural reservoirs. A group of STEC O157:H7 with a dramatic combination of high virulence potentials and super-shedder bovine origin have been isolated. Here, an STEC O157:H7 isolate, JEONG-1266, was analyzed by comparative genomics, stx genotyping, and phenotypic analyses. The phylogenetic typing and whole-genome comparison consistently showed that JEONG-1266 is genetically close to EC4115 (one of 2006 Spinach outbreak isolates) and SS17 (an isolate from super-shedder cattle) strains, all of which belong to lineage I/II and Clade 8. Both lineage I/II and Clade 8 are known to be mostly associated with clinical strains with high virulence and severe clinical symptoms. Further, JEONG-1266, like EC4115 and SS17, harbors stx2a/stx2c genes, and carries Stx-encoding prophages, specifically the φstx2a-γ subtype. Possession of the φstx2a-γ subtype of Stx-encoding prophages and production of Stx2a have been shown to be a key signature associated with hypervirulent STEC O157:H7 strains. In silico virulence typing elucidated JEONG-1266, EC4115, and SS17 shared a highly conserved profile of key virulence genes at the nucleotide sequence level. Consistently, phenotypic data showed that JEONG-1266 expressed a high level of Stx2 toxins and had the full capacity of adhesion in vitro. Taken together, our study suggests that JEONG-1266 may represent an emerging STEC O157:H7 group, which are hypervirulent strains that originate from super-shedders, that can be a threat to food safety and public health.

The emergence of extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase producing Escherichia coli represent a contemporary public health threat. ESBL and AmpC β-lactamase genes translocate between chromosomes and plasmids, facilitating rapid spread throughout the environment. In this study, ESBL/AmpC producing bacteria were isolated from beef cattle farms with seldom antibiotic use. Eleven farms out of 17 tested, had ESBL/AmpC producing E. coli in animals, soil, and forage samples. Fifty-nine CTX-M or CMY-2 positive E. coli isolates were further characterized with whole-genome sequencing. The isolates commonly carried CMY-2, TEM, or CTX-M genes, and over half encoded both CTX-M and TEM genes. Using comparative genomics, antimicrobial resistance genes from 12 classes of antimicrobial were identified and confirmed by antibiotic susceptibility test, revealing multidrug resistance against multiple classes of antibiotics. Virulence factors related to adherence, invasion, iron uptake, and bacterial secretion systems were shared by all isolates; some of which were identified as enteropathogenic E. coli. Phylogenetic analyses revealed a pattern of close genetic relatedness, suggesting that ESBL/AmpC producing E. coli were transmitted among farms as well as independent evolution within farms. Our results indicate that ESBL and AmpC β-lactamases prevail in food animal production system regardless antibiotic use and have the characteristics for zoonotic transmission.

Abstract Background As microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins, and other constituents, the detailed identification and discrimination of the growth phases of bacterial populations in batch culture is challenging. Cell analysis is indispensable for quality control and cell enrichment. Methods In this paper, we report the results of our investigation on the use of single-cell Raman spectrometry (SCRS) for real-time analysis and prediction of cells in different growth phases during batch culture of Lactobacillus (L.) casei Zhang. A targeted analysis of defined cell growth phases at the level of the single cell, including lag phase, log phase, and stationary phase, was facilitated by SCRS. Results Spectral shifts were identified in different states of cell growth that reflect biochemical changes specific to each cell growth phase. Raman peaks associated with DNA and RNA displayed a decrease in intensity over time, whereas protein-specific and lipid-specific Raman vibrations increased at different rates. Furthermore, a supervised classification model (Random Forest) was used to specify the lag phase, log phase, and stationary phase of cells based on SCRS, and a mean sensitivity of 90.7% and mean specificity of 90.8% were achieved. In addition, the correct cell type was predicted at an accuracy of approximately 91.2%. Conclusions To conclude, Raman spectroscopy allows label-free, continuous monitoring of cell growth, which may facilitate more accurate estimates of the growth states of lactic acid bacterial populations during fermented batch culture in industry.