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A deformed superalloy with γ′ content reaching 73% has been designed by ourselves. In this work, the problems of preparation and deformation caused by the high γ′ phase content were solved by the electron beam smelting layered solidification technique (EBS-LST) and hot extrusion. Initially, the superalloy with low segregation and fine microstructure was prepared by EBS-LST, followed by conducting hot deformation experiments at different temperatures and strain rates. The compression curves are corrected, and the constitutive model, recrystallization models and thermo-mechanical processing maps were established based on the corrected curves, and the recrystallization mechanisms were analyzed by TEM and EBSD. Finally, the suitable hot extrusion parameters were obtained indirectly through the hot processing map, and the designed alloy was hot extruded. The microstructure of the extruded alloy is free of cracks and is characterized by fine equiaxed grains.

Sonodynamic therapy (SDT) presents significant advantages, such as improved tissue penetration, non-invasiveness, and reduced susceptibility to drug resistance, positioning it as a promising modality in the biomedical domain. Recent advancements in the structural modification and component optimization of sonosensitizers have markedly enhanced the efficacy of SDT, especially in the production of reactive oxygen species (ROS). Additionally, sonosensitizers can be engineered into functional particles through various methodologies, thereby achieving enhanced biocompatibility and catalytic efficiency. This review concentrates on recent advancements in sonosensitizers, with a particular emphasis on piezoelectric materials and conjugated polymers (CPs). These innovations have shown promise in the treatment of pathogenic microbial infections, the targeting of cancer cells, and the enhancement of 3D bioprinting techniques for wound repair. Furthermore, the review discusses the primary challenges and prospective future directions for the biomedical applications of these materials.

Abstract Background A stable public health workforce plays an indispensable role in the realization of the goal of health for all. However, there is an exodus of public health workers from the Centers for Disease Control and Prevention (CDC). Given the limited evidence on the mechanisms shaping turnover intention (TI) among public health workers, the study aims to investigate the triggering mechanisms of high and low turnover intention by combining job demands, job resources, and personal resources through a set theory perspective based on the Job-Demand-Resources (JD-R) model. Methods The cross-sectional study was conducted from September 7 to 18, 2020 at district (county) level CDC in Liaoning Province, China. A total of 584 public health professionals were included. Overcommitment, effort, social respect, occupational identity, job rewards, self-efficacy, and psychological resilience were included in the study as configuration factors. The data were gathered through an online questionnaire and were analyzed using multiple regression and fuzzy-set Qualitative Comparative Analysis (fsQCA). Results Social respect (B = -0.682, P

Abstract Background The shortage of public health personnel and the uneven distribution between urban and rural areas are thorny issues in China. Master of public health (MPH) is an integral part of public health human resources in the future, and it is of far-reaching significance to discuss their work preferences. The present study wants to investigate the job preference of MPH, understand the relative importance of different job attributes, and then put forward targeted incentive measures. Methods Discrete choice experiment (DCE) was used to evaluate the job preference of MPHs in two medical colleges in Liaoning Province. Attributes include employment location, bianzhi, working environment, career development prospects, work value and monthly income. Thirty-six choice sets were developed using a fractional factorial design. Mixed logit models were used to analysis the DCE data. Results The final sample comprised 327 MPHs. All the attributes and levels included in the study are statistically significant. Monthly income is the most important factor for MPHs. For non-economic factors, they value career development prospects most, followed by the employment location. Respondents’ preferences are heterogeneous and influenced by individual characteristics. Subgroup analysis showed that respondents from different family backgrounds have different job preferences. Policy simulation suggested that respondents were most sensitive to a salary increase, and the combination of several non-economic factors can also achieve the same effect. Conclusions Economic factors and non-economic factors significantly affect the job preference of MPHs. To alleviate the shortage and uneven distribution of public health personnel, more effective policy intervention should comprehensively consider the incentive measures of the work itself and pay attention to the individual characteristics and family backgrounds of the target object.

Hypertension is a leading cause of morbidity and mortality worldwide and poses a major risk factor for cardiovascular diseases and chronic kidney disease. Research has shown that nitric oxide (NO) is a vasodilator that regulates vascular tension and the decrease of NO bioactivity is considered one of the potential pathogenesis of essential hypertension. The L-arginine-nitric oxide synthase (NOS) pathway is the main source of endogenous NO production. However, with aging or the onset of diseases, the function of the NOS system becomes impaired, leading to insufficient NO production. The nitrate–nitrite–NO pathway allows for the generation of biologically active NO independent of the NOS system, by utilizing endogenous or dietary inorganic nitrate and nitrite through a series of reduction cycles. The oral cavity serves as an important interface between the body and the environment, and dysbiosis or disruption of the oral microbiota has negative effects on blood pressure regulation. In this review, we explore the role of oral microbiota in maintaining blood pressure homeostasis, particularly the connection between nitrate-reducing bacteria and the bioavailability of NO in the bloodstream and blood pressure changes. This review aims to elucidate the potential mechanisms by which oral nitrate-reducing bacteria contribute to blood pressure homeostasis and to highlight the use of oral nitrate-reducing bacteria as probiotics for oral microbiota intervention to prevent hypertension.

Photodynamic therapy (PDT) is an effective method for treating microbial infections by leveraging the unique photophysical properties of photosensitizing agents, but issues such as fluorescence quenching and the restricted generation of reactive oxygen species (ROS) under hypoxic conditions still remain. In this study, we successfully synthesized and designed a coumarin-based aggregation-induced emission luminogen (AIEgen), called ICM, that shows a remarkable capacity for type I ROS and type II ROS generation. The 1O2 yield of ICM is 0.839. The ROS it produces include hydroxyl radicals (HO•) and superoxide anions (O2•−), with highly effective antibacterial properties specifically targeting Staphylococcus aureus (a Gram-positive bacterium). Furthermore, ICM enables broad-spectrum fluorescence imaging and exhibits excellent biocompatibility. Consequently, ICM, as a potent type I photosensitizer for eliminating pathogenic microorganisms, represents a promising tool in addressing the threat posed by these pathogens.

Droop control is widely used in multi-terminal flexible DC (VSC-MTDC) transmission systems by virtue of the advantage of multi-station cooperative unbalanced power dissipation, however, the essence of the droop control strategy is to change the DC current to realize the unbalanced power dissipation, and the resulting DC voltage deviation will affect the normal operation of the system. Firstly, this paper theoretically analyses the working characteristics of the conventional droop control and proposes a control method to realize the quasi-differential-free regulation of DC voltage by translating the droop curve. Second, according to the power margin of the converter station, the feedforward compensation amount of each converter station is reasonably set to avoid the power impact on the converter station. Finally, for the problem that the actual value of DC voltage still deviates from the rated value, a control strategy containing secondary regulation of DC voltage is proposed to further restore the DC voltage to the initial value on the basis of ensuring the effect of power regulation, which improves the stability of the operation of the VSC-MTDC system. The final simulation results verify the effectiveness of the proposed method.

Extracellular vesicles (EVs) are tiny lipid bilayer-enclosed membrane particles released from a variety of cell types into the surrounding environment. These EVs have massive participated in cell-to-cell communication and interspecies communication. In recent years, plant-derived extracellular vesicles (PDEVs) and “exosome-like” EVs populations found in distinct plants have attracted widespread attention. Especially, research on medicinal plant-derived extracellular vesicles (MPDEVs) are increasing, which are considered a kind of promising natural compound. This review summarizes current knowledge on MPDEVs in terms of bioactive compounds, including small RNA, protein, lipid, and metabolite, have been found on the surface and/or in the lumen of MPDEVs. Moreover, both in vitro and in vivo experiments have shown that MPDEVs exert broad biomedical functions, such as anti-inflammatory, anticancer, antioxidant, modulate microbiota, etc. MPDEVs may be a better substitute than animal-derived extracellular vesicles (ADEVs) because of safety and biocompatibility in the future.

Abstract Background Early studies have shown a relationship between activities of daily living (ADL) disability and depressive symptoms in older people. However, discussions on the direction of this relationship are insufficient. The study’s objective was to assess the reciprocal relationship between ADL disability and depressive symptoms among middle-aged and older Chinese people. Method Data was collected in four waves of a nationwide survey, the China Health and Retirement Longitudinal Study (CHARLS), which was carried out in 2011, 2013, 2015, and 2018. In total, this study included 4,124 participants aged ≥ 45 years at baseline. A summing score of the eleven items for basic activities of daily living (BADL) and instrumental activities of daily living (IADL) was calculated to indicate the degree of ADL disability. The 10-item Centre for Epidemiological Studies Depression Scale (CESD-10) was adopted to measure depressive symptoms. The reciprocal relationship between ADL disability and depressive symptoms was tested by cross-lagged models. Result At baseline, 911 (22.1%) participants were classified as having difficulties with ADL, and the prevalence of depressive symptoms was 34.4% (1,418). Among middle-aged and older people in China, there was a significant reciprocal and longitudinal relationship between ADL disability and depressive symptoms. People who had difficulty with ADL faced a higher risk of depressive symptoms, and those who suffered from depressive symptoms were accompanied by an increase in ADL disability in the following years. The subgroup analysis on age also showed that ADL disability was reciprocally and longitudinally related to depressive symptoms. However, only women showed similar results in the subgroup analysis on gender. Conclusion This study shows that ADL disability is bi-directionally related to depressive symptoms in middle-aged and older Chinese people over time. The results suggest we should identify ADL disability and bad psychological conditions in time to prevent subsequent mutual damage among middle-aged and older Chinese people, a vulnerable group rising in the future.

Summary: The efficient conversion of CO2 is considered to be an important step toward carbon emissions peak and carbon neutrality. Presently, great efforts have been devoted to the study of efficient nanocatalysts, electrolytic cell, and electrolytes to achieve high reactivity and selectivity in the electrochemical reduction of CO2 to mono- and multi-carbon (C2+) compounds. However, there are very few reviews focusing on highly reactive and selective ethylene production and application in the field of electrochemical carbon dioxide reduction reaction (CO2RR). Ethylene is a class of multi-carbon compounds that are widely applied in industrial, ecological, and agricultural fields. This review focuses especially on the convertibility of CO2 reduction to generate ethylene technology in practical applications and provides a detailed summary of the latest technologies for the efficient production of ethylene by CO2RR and suggests the potential application of CO2RR systems in food science to further expand the application market of CO2RR for ethylene production.

As a zoonotic parasite, Cryptosporidium spp. could cause severe diarrhea mainly in calves and children globally. Monitoring and prevention of Cryptosporidium spp.’s prevalence is of great significance in both economy and public health aspects. In this study, specific primers and probes were designed within the conserved region of 18S rRNA gene for Cryptosporidium spp. and recombinase polymerase amplification assays based on the fluorescence monitoring (real-time RPA) as well as combined with a lateral flow strip (LFS RPA) were developed. Both of the two RPA assays allowed the exponential amplification of the target fragment within 20 min. After incubation on a metal bath at 42 °C, the LFS RPA results were displayed on the lateral flow strip within 5 min while real-time RPA allowed the real-time observation of the results in Genie III at 39 °C. The RPA assays showed high specificity for Cryptosporidium spp. without any cross-reaction with other tested pathogens causing diarrhea in cattle. With the recombinant plasmid DNA containing the 18S rRNA gene of Cryptosporidium spp. serving as a template, the limit of detection for real-time RPA and LFS RPA assays were 14.6 and 12.7 copies/reaction, respectively. Moreover, the RPA assays were validated by testing diarrheic cattle fecal samples and compared with a real-time PCR. The positive ratio of Cryptosporidium spp. was 24.04 % (44/183) and 26.23 % (48/183) in both RPA assays and real-time PCR assay, respectively, and the kappa coefficient value was 0.942. The diagnostic specificity and diagnostic sensitivity of both RPA assays were 100 % and 91.67 %, respectively. Forty-one of 48 positive samples were successfully sequenced and four Cryptosporidium species were detected, including C. parvum (n = 20), C. andersoni (n = 17), C. bovis (n = 3) and C. ryanae (n = 1). The developed RPA assays are easy to operate and faster to obtain the detection results, and they are suiting for the point-of-care detection and facilitating the prevention and control of Cryptosporidium spp. infections.

Abstract To efficiently combat viral infectious diseases, it is important to develop broadly applicable countermeasures, and efficient antiviral systems can be developed by elaborating the relationship of antiviral efficiency with the interactions between antiviral agents and viruses. In the present study, conjugated polymer (CP)-based photodynamic therapy was used to inhibit RNA virus infections. A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudotyped virus composed of an SARS-CoV-2 envelope coated with the S protein and luciferase RNA genome was employed to assess antiviral efficiency. Three cationic CPs with different backbone structures, fluorene-co-phenylene (PFP), thiophene (PMNT), and phenylene vinylene (PPV), exhibit different photoinactivation effects. The highly efficient photoinactivation of PPV and PMNT is derived from the complete photodegradation of spike proteins, nucleocapsid proteins and nucleic acids of SARS-CoV-2 after binding to the viral spike proteins. Although PFP showed the highest efficiency in the photodegradation of spike proteins due to its strong binding affinity, ineffective viral inhibition was observed, which occurred because the viral gene was partially damaged under light irradiation and the process of delivering the viral gene to cells received assistance. This work preliminarily reveals the effect of CP-virus interactions on their photoinactivation activity and should be beneficial for further research on the development of highly efficient antiviral PDT agents.

Duck is often used in meat fraud as a substitute for more expensive meats. Rapid detection of duck ingredient in meat products is of great significance for combating meat fraud and safeguarding the interests of consumers. Therefore, we aim to develop duck-specific recombinase polymerase amplification (RPA)-based assays for the rapid detection of duck ingredient in animal-derived foods. Using Cytb gene as target, the real-time RPA and RPA combined with lateral flow strips (LFS RPA) were developed successfully for the rapid detection of ducks in 20 min at 39 °C and 40 °C, respectively. The assays did not show cross-reactions with 6 other livestock and poultry. The developed RPA assays could detect 10 pg duck genomic DNA per reaction and 0.1 % (w/w) duck ingredient in duck and mutton mixed powder within 30 min, including a rapid nucleic acid extraction. Furthermore, duck ingredient could be detected in 30 different actual foods including heat-processed meats and blood products. Therefore, duck-specific real-time RPA and LFS RPA assays were successfully developed with good specificity and sensitivity, which could enable rapid detection of duck ingredient in the field and provide technical support for combating the meat fraud.

Abstract Background Bovine rotavirus A (BRVA) is considered to be the most common pathogen of severe diarrhea in cattle worldwide, which could lead to the death of newborn calves and cause the significant economic losses to the cattle industry. As a novel isothermal nucleic acid amplification technique, recombinase polymerase amplification (RPA) has been applied widely for the rapid detection of different important pathogens in human and animals. Results An RT-RPA assay based on the real time fluorescence monitoring (real-time RT-RPA) and an RT-RPA assay combined with a lateral flow strip (LFS RT-RPA) were successfully developed by targeting the VP6 gene of BRVA. The RT-RPA assays allowed the exponential amplification of the target fragment in 20 min. After incubation of the LFS RT-RPA on a metal bath at 40 °C, the results were displayed on the lateral flow strip within 5 min, while real-time RT-RPA allowed the real-time observation of the results in Genie III at 42 °C. Both of the two assays showed high specificity for BRVA without any cross-reaction with the other tested pathogens causing diarrhea in cattle. With the standard RNA of BRVA serving as a template, the limit of detection for real-time RT-RPA and LFS RT-RPA were 1.4 × 102 copies per reaction and 1.4 × 101 copies per reaction, respectively. In the 134 fecal samples collected from cattle with diarrhea, the BRVA positive rate were 45.52% (61/134) and 46.27% (62/134) in real-time RT-RPA and LFS RT-RPA, respectively. Compared to a previously published real-time PCR, the real-time RT-RPA and LFS RT-RPA showed a diagnostic specificity of 100%, diagnostic sensitivity of 98.39% and 100%, and a kappa coefficient of 0.985 and 1.0, respectively. Conclusions In this study, BRVA was successfully detected in cattle fecal samples by the developed real-time RT-RPA and LFS RT-RPA assays. The developed RT-RPA assays had great potential for the rapid detection of BRVA in under-equipped diagnostic laboratory and the point-of-need diagnosis at quarantine stations and farms, which is of great importance to control BRVA-associated diarrhea in cattle herds.

Infectious disease outbreaks have seriously endangered global health owing to the scarcity of testing materials and techniques. Diversified materials and methods should be urgently developed for rapid detection and discrimination of pathogenic microorganisms. Conjugated polymer (CP) materials are macromolecular compounds comprising numerous covalently bonded luminescent units. They have excellent light-harvesting and optical signal amplification capabilities owing to the transmission of excitation energy along their backbone. In recent years, CP materials have aroused research enthusiasm in the biosensors field because of their outstanding optoelectronic properties. This brief manuscript provides an overall review of recent progress achieved in CP-based systems for pathogen sensing.

The surface defect detection of automobile pipe joints based on computer vision faces technical challenges. The tiny-sized and smooth surfaces with processing textures will undermine the defect detection accuracy. In order to solve this problem, a new method was proposed, which combines wavelet decomposition and reconstruction with the canny operator to detect defects, and then uses the multi-channel fusion convolutional neural network to identify the types of defects. Firstly, illumination compensation technology is used to obtain a more uniform gray distribution of the original image. Then, the wavelet decomposition and reconstruction are used to remove noises and processing textures. Furthermore, the defect regions are segmented using the canny operator and hole filling from the image. Finally, the multi-channel fusion convolutional neural network of decision-level is used to identify the surface defect types. This method provides an idea for the surface defects detection of automobile pipe joints with serious interference, such as smooth surface, random noises, and processing textures. The experimental results reveal that the method can effectively eliminate the influence of uneven illumination, random noises, and processing textures and achieve high defect classification accuracy.

Background: To evaluate the clinical efficacy and safety of the modified laparoscopic inverted triangle model for extended lesion resection in treating dysmenorrhea focal adenomyosis in women who have completed childbirth. Methods: A total of 52 patients with dysmenorrhea focal adenomyosis treated in the Department of Gynecology of the Affiliated Changzhou Second People’s Hospital of Nanjing Medical University from July 2014 to August 2020 were retrospectively analyzed. They underwent the modified laparoscopic inverted triangle model for extended lesion resection. The scope of resection included the focal adenomyosis lesions and along with part of the surrounding normal myometrial tissue and endometrium in order to ensure full resection of adenomyosis lesions without residual. Surgical outcome and adverse effects on ovarian functions were evaluated through the retrospective analysis compared the changes of dysmenorrhea visual analog scale (VAS) score changes, uterine volume changes, changes in serum CA125 level, and serum anti-mullerian hormone (AMH) level changes prior to surgery as well as 3, 6, 12, and 24 months after surgery. Results: All operations were completed by laparoscopy without conversion to laparotomy. No serious complications occurred during or after surgery. The dysmenorrhea VAS score, uterine volume, and serum CA125 level at 3, 6, 12, and 24 months after surgery were significantly lower than baseline and the difference was statistically significant. The serum AMH level showed a downward trend 3 months after surgery compared with the pre-surgery level, but the difference was not statistically significant (p = 0.27). The response rates at 3, 6, 12, and 24 months after surgery were 98.1%, 98.1%, 96.1%, and 88.5%, respectively, and the complete response rates were 30.8%, 34.6%, 34.6%, and 21.1%, respectively. Conclusions: Modified laparoscopic inverted triangle model for extended lesion resection is a safe and effective conservative surgical method for treating dysmenorrhea focal adenomyosis.

BackgroundRecent evidence suggests that enhancer RNAs (eRNAs) play key roles in cancers. Identification of immune-related eRNAs (ireRNAs) in melanoma can provide novel insights into the mechanisms underlying its genesis and progression, along with potential therapeutic targets.AimTo establish an ireRNA-related prognostic signature for melanoma and identify potential drug candidates.MethodsThe ireRNAs associated with the overall survival (OS-ireRNAs) of melanoma patients were screened using data from The Cancer Genome Atlas (TCGA) via WGCNA and univariate Cox analysis. A prognostic signature based on these OS-ireRNAs was then constructed by performing the least absolute shrinkage and selection operator (LASSO) Cox regression analysis. The immune landscape associated with the prognostic model was evaluated by the ESTIMATE algorithm and CIBERSORT method. Finally, the potential drug candidates for melanoma were screened through the cMap database.ResultsA total of 24 OS-ireRNAs were obtained, of which 7 ireRNAs were used to construct a prognostic signature. The ireRNAs-related signature performed well in predicting the overall survival (OS) of melanoma patients. The risk score of the established signature was further verified as an independent risk factor, and was associated with the unique tumor microenvironment in melanoma. We also identified several potential anti-cancer drugs for melanoma, of which corticosterone ranked first.ConclusionsThe ireRNA-related signature is an effective prognostic predictor and provides reliable information to better understand the mechanism of ireRNAs in the progression of melanoma.

Hepatitis E virus (HEV) is a zoonotic pathogen that causes global hepatitis E. Outbreaks of hepatitis E are directly linked to the consumption of pork liver products. Herein reverse transcription recombinase polymerase amplification assays targeting the ORF2 gene were developed for the rapid detection of HEV by integrating the fluorescence detection platform (qRT-RPA) and the visible lateral flow biosensor by naked eyes (LFB RT-RPA). The qRT-RPA assay effectively detected HEV RNA with a limit of detection (LOD) of 154 copies/μl (95%CI: 126–333 copies/µl) in Genie III at 41°C for 20 min. Besides this, the LFB RT-RPA detected the HEV RNA with a LOD of 24 copies/μl (95%CI: 20–57 copies/µl) in an incubator block at 41°C for 20 min. The developed RT-RPA assays also showed good specificity for HEV, with no cross-reactions with any of the other important swine pathogens examined in this work. The performance of the developed RT-RPA assays was validated on 14 HEV RNA-positive and 66 HEV RNA-negative raw pork liver samples identified by a previously described qRT-PCR. Consequently, 11 and 12 samples were HEV RNA-positive as detected by the qRT-RPA and the LFB RT-RPA, respectively. Compared to qRT-PCR, the qRT-RPA and LFB RT- RPA assays revealed a coincidence rate of 96.3 and 97.5% as well as a Kappa value of 0.858 and 0.908, respectively. These results ascertain that the developed RT-RPA assays are effective diagnostic tools for the point-of-care detection of HEV in resource-limited settings.

BackgroundEndometrioid adenocarcinoma (EAC) is the most common subtype of endometrial cancer (EC) and is an estrogen-related cancer. In this study, we sought to investigate the expressions and mechanism of action of 17β-estradiol (E2) and long noncoding RNA (lncRNA) LINC01541 in G1/G2 EAC samples.MethodsThe expressions of estrogen receptor β (ESR2), LINC01541, miR-200s, and VEGFA were evaluated using real-time PCR in human EAC tissues (n = 8) and adjacent normal tissues (n = 8). Two EC cell lines (Ishikawa and RL95-2) were selected for validation in vitro. Bioinformatics analyses and luciferase reporter analyses were performed to verify potential binding sites. qRT-PCR, Western blot, and CCK-8 were used to identify the regulatory mechanisms of related genes in cell biological behavior.ResultsCompared with adjacent normal tissues, LINC01541 and miR-200s family (except miR-200c) were highly expressed in EAC tissues (n=8), while ESR2 and VEGFA were lowly expressed in EAC tissues (* P < 0.05; ** P < 0.01). In vitro: E2 inhibited the expression of LINC01541 and miR-429 in both cell lines, and estrogen antagonist (PHTPP) could reverse this effect, in addition, PHTPP could promote the proliferation of these two cancer cells, cell transfection LINC01541 also had this effect after overexpression of plasmid and miR-429 mimic. E2 promotes the expression of VEGFA in both cell lines, and PHTPP can also reverse this effect. LINC01541 interacts with miR-429 to promote the expression of each other, and both inhibit the synthesis of VEGFA in EAC cells after overexpression. Through the double validation of bioinformatics analysis and dual fluorescein reporter gene, it was confirmed that miR-429 targets the regulation of VEGFA expression (* P < 0.05; ** P < 0.01).ConclusionE2 promotes the synthesis of VEGFA by altering the expression levels of LINC01541 and miR-429 in EAC, thereby affecting the angiogenesis process of EAC. Also, E2-mediated LINC01541/miR-429 expression may affect cell migration in EAC. In addition, we identified a reciprocal promotion between LINC01541 and miR-429.

Bovine kobuvirus (BKV) is a novel kobuvirus considered to be closely related to calf diarrhea and has become a worldwide epidemic. Currently, the BKV lacks an efficient and convenient detection method to assist the research on BKV prevalence. In this study, a new and specific TaqMan-based real-time RT-PCR for the detection of BKV was developed using the conserved region of the 3D gene. The assay was highly specific for BKV, without cross-amplification with other non-targeted pathogens. The limit of detection of this assay was 102 copies. Standard curves showed a strong linear correlation from 102 to 106 copies of BKV standard RNA per reaction, and the parameters revealed as a slope of −3.54, efficiency of 91.64%, and regression coefficients (R2) of 0.998. The assay was also reproducible, with the intra-assay and inter-assay coefficient of variation

The pulse-jet cleaning process is a critical part of the bag filter workflow. The dust-cleaning effect has a significant impact on the operating stability of bag filters. Aiming at the multi-parameter optimization problem involved in the pulse-jet cleaning process of bag filters, the construction method of hybrid surrogate models based on second-order polynomial response surface models (PRSMs), radial basis functions (RBFs), and Kriging sub-surrogate models is investigated. With four sub-surrogate model hybrid modes, the corresponding hybrid surrogate models, namely PR-HSM, PK-HSM, RK-HSM, and PRK-HSM, are constructed for the multi-parameter optimization involved in the pulse-jet cleaning process of bag filters, and their objective function is the average pressure on the inner side wall of the filter bag at 1 m from the bag bottom. The genetic algorithm is applied to search for the optimal parameter combination of the pulse-jet cleaning process. The results of simulation experiments and optimization calculations show that compared with the sub-surrogate model PRSM, the evaluation indices RMSE, R2, and RAAE of the hybrid surrogate model RK-HSM are 9.91%, 4.41%, and 15.60% better, respectively, which greatly enhances the reliability and practicability of the hybrid surrogate model. After using the RK-HSM, the optimized average pressure F on the inner side wall of the filter bag at 1 m from the bag bottom is −1205.1605 Pa, which is 1321.4543 Pa higher than the average pressure value under the initial parameter condition set by experience, and 58.4012 Pa to 515.2836 Pa higher than using the three sub-surrogate models, verifying its usefulness.

The linear motor feed system has been in service in complex working conditions for a long time, thus causing the nonuniform distribution of the temperature field distribution. Thus, the thermal error has become a key factor affecting system motion accuracy. In order to maximize the accuracy and efficiency of thermal error compensation for linear motor feed systems, an improved modeling method for the thermal error of the linear motor feed system based on Bayesian neural networks is proposed in combination with the strong generalization performance and avoidance of overfitting of Bayesian neural networks. And the specific modeling ideas are as follows: Firstly, the X-Y cross-type two-axis linear motor feed system is taken as the test object. Due to the traditional neural network’s slow convergence, overfitting, and underfitting problems, the Bayesian neural network is used to model the thermal error of the linear motor feed system. Secondly, to avoid the influence of multicollinearity data on the final results, the grey relation analysis method is used to screen the temperature measuring points. The data with a large relation degree is selected for modeling to ensure the prediction accuracy of the neural network. Thirdly, the temperature variables of sensitive points and thermal positioning errors are taken as data input samples. Fourthly, a Bayesian neural network model is established. Fifthly, the hyperparameters of the Bayesian neural network are determined by a calculating method of Hessian matrix by Gauss-Newton approximation. And finally, a thermal error prediction model is established. The comparison and analysis with the neural network constructed by the ordinary Levenberg-Marquardt algorithm after a series of experimental demonstrations see that the prediction accuracy of the proposed method can be enhanced by up to 10%. It also shows that the prediction model has the advantages of high precision, strong generalization ability, anti-disturbance solid ability, and strong robustness, etc. Therefore, the prediction model is expected to be widely used in predicting and compensating thermal error of the feed system of high-speed CNC machine tools in practical machining occasions.

Objective To establish a real-time recombinase-aid amplification (RAA) method for rapid detection of Pseudomonas aeruginosa. Methods Specific primers and exo probes based on ecfX gene of P. aeruginosa were designed in this study, and the validity of the method was evaluated by sensitivity, specificity and suspected strains detection. Results Real-time RAA was performed successfully at 39℃ for 20 min. Only the P. aeruginosa strains but not other bacteria were amplified, showing the good specificity. The limit of detection was 3.0×103 fg genomic DNA per reaction, and 1.0×103 CFU P. aeruginosa pure culture per reaction. The developed real-time RAA was further evaluated on 36 suspected of P. aeruginosa, which were identified successfully to be P. aeruginosa.The detection result were the same with those of a real-time PCR assay and the VITEK 2 Compact. Conclusion The developed real-time RAA assay is a rapid, simple and reliable tool for accurate detection of P. aeruginosa of diverse origins.

Abstract Background Mycoplasmal pneumonia is an important infectious disease that threatens sheep and goat production worldwide, and Mycoplasma ovipneumoniae is one of major etiological agent causing mycoplasmal pneumonia. Recombinase polymerase amplification (RPA) is an isothermal nucleic acid amplification technique, and RPA-based diagnostic assays have been described for the detection of different types of pathogens. Results The RPA assays using real-time fluorescence detection (real-time RPA) and lateral flow strip detection (LFS RPA) were developed to detect M. ovipneumoniae targeting a conserved region of the 16S rRNA gene. Real-time RPA was performed in a portable florescence scanner at 39 °C for 20 min. LFS RPA was performed in a portable metal bath incubator at 39 °C for 15 min, and the amplicons were visualized with the naked eyes within 5 min on the lateral flow strip. Both assays were highly specific for M. ovipneumoniae, as there were no cross-reactions with other microorganisms tested, especially the pathogens involved in respiratory complex and other mycoplasmas frequently identified in ruminants. The limit of detection of LFS RPA assay was 1.0 × 101 copies per reaction using a recombinant plasmid containing target gene as template, which is 10 times lower than the limit of detection of the real-time RPA and real-time PCR assays. The RPA assays were further validated on 111 clinical sheep nasal swab and fresh lung samples, and M. ovipneumoniae DNA was detected in 29 samples in the real-time RPA, 31 samples in the LFS RPA and 32 samples in the real-time PCR assay. Compared to real-time PCR, the real-time RPA and LFS RPA showed diagnostic specificity of 100 and 98.73%, diagnostic sensitivity of 90.63 and 93.75%, and a kappa coefficient of 0.932 and 0.934, respectively. Conclusions The developed real-time RPA and LFS RPA assays provide the attractive and promising tools for rapid, convenient and reliable detection of M. ovipneumoniae in sheep, especially in resource-limited settings. However, the effectiveness of the developed RPA assays in the detection of M. ovipneumoniae in goats needs to be further validated.

Both insect ecdysone receptors and ultraspiracle belong to the nuclear receptor family. They form a nanoscale self-assembling complex with ecdysteroids in cells, transit into the nucleus, bind with genes to initiate transcription, and perform specific biological functions to regulate the molting, metamorphosis, and growth processes of insects. Therefore, this complex is an important target for the development of eco-friendly insecticides. The diamondback moth (Plutella xylostella) is a devastating pest of cruciferous vegetable crops, wreaking havoc worldwide and causing severe economic losses, and this pest has developed resistance to most chemical insecticides. In this study, highly pure EcR and USP functional domains were obtained by constructing a prokaryotic expression system for the diamondback moth EcR and USP functional domain genes, and the differences between EcR and USP binding domain monomers and dimers were analyzed using transmission electron microscopy and zeta potential. Radioisotope experiments further confirmed that the binding affinity of PonA to the EcR/USP dimer was enhanced approximately 20-fold compared with the binding affinity to the PxGST−EcR monomer. The differences between PonA and tebufenozide in binding with EcR/USP were examined. Molecular simulations showed that the hydrogen bonding network formed by Glu307 and Arg382 on the EcR/USP dimer was a key factor in the affinity enhancement. This study provides a rapid and sensitive method for screening ecdysone agonists for ecdysone receptor studies in vitro.

With the development of wearable electronic devices, conductive polymer composites (CPCs) based flexible strain sensors are gaining tremendous popularity. In recent years, the applications of additive manufacturing (AM) technology (also known as 3D printing) in fabricating CPCs based flexible strain sensors have attracted the attention of researchers due to their advantages of mold-free structure, low cost, short time, and high accuracy. AM technology, based on material extrusion, photocuring, and laser sintering, produces complex and high-precision CPCs based wearable sensors through layer-by-layer stacking of printing material. Some high-performance CPCs based strain sensors are developed by employing different 3D printing technologies and printing materials. In this mini-review, we summarize and discuss the performance and applications of 3D printed CPCs based strain sensors in recent years. Finally, the current challenges and prospects of 3D printed strain sensors are also discussed to provide an insight into the future of strain sensors using 3D printing technology.

Abstract Cationic conjugated polymers (CCPs) have been attracting a lot of attention in biomedical applications because of their good photoelectric properties and good cell viability. However, positively charged components may reduce the electrostatic repulsion among red blood cells (RBCs) and induce RBC aggregation, which may lead to thrombus. Herein, in this work, we prepared the complexes of CCPs and outer membrane vesicles (OMVs) to inhibit RBC aggregation induced by CCPs and improve the biocompatibility of CCPs. A poly(fluorene-co-phenylene) derivative (PFP), a poly(p-phenylenevinylene) derivative (PPV), and a poly(thiophene) derivative (PMNT) were chosen as the model CCPs, and OMVs were used as the representative of a cell membrane. The CCP–OMV complexes were formed mainly driven by electrostatic interactions. Besides, the electrostatic CCP–OMV complexes were proved to be able to prevent the RBC aggregation induced by CCPs while maintaining the hydrophobic interactions between CCPs and RBCs.

Abstract Background Vibrio parahaemolyticus (V. parahaemolyticus) is a leading cause of food poisoning and is of great importance to public health due to the frequency and seriousness of the diseases. The simple, timely and efficient detection of this pathogen is a major concern worldwide. In this study, we established a simple and rapid method based on recombinase polymerase amplification (RPA) for the determination of V. parahaemolyticus. According to the gyrB gene sequences of V. parahaemolyticus available in GenBank, specific primers and an exo probe were designed for establishing real-time recombinase polymerase amplification (real-time RPA). Results The real-time RPA reaction was performed successfully at 38 °C, and results were obtained within 20 min. The method only detected V. parahaemolyticus and did not show cross-reaction with other bacteria, exhibiting a high level of specificity. The study showed that the detection limit (LOD) of real-time RPA was 1.02 × 102 copies/reaction. For artificially contaminated samples with different bacteria concentrations, V. parahaemolyticus could be detected within 5–12 min by real-time RPA in oyster sauce, codfish and sleeve-fish at concentrations as low as 4 CFU/25 g, 1 CFU/25 g and 7 CFU/25 g, respectively, after enrichment for 6 h, but were detected in a minimum of 35 min by real-time PCR (Ct values between 27 and 32). Conclusion This study describes a simple, rapid, and reliable method for the detection of V. parahaemolyticus, which could potentially be applied in the research laboratory and disease diagnosis.

The present study investigated the role and mechanism of SUMO2/3 in the protection of vascular endothelial cells by propofol. An ischemia-reperfusion (I/R) injury model of human umbilical vein endothelial cells (HUVECs) was constructed. After treatment with propofol, we determined the expression of SUMO2/3 proteins by Western blotting, cell proliferation by CCK-8 assay, cell migration by Transwell assay and apoptosis by flow cytometry. After interference of SUMO2/3, the biological functions of HUVECs were observed. Using Western blotting and laser scanning confocal microscopy, the autophagy of HUVECs was examined. Using immunoprecipitation, the SUMO modification site of Beclin1 was examined. The results showed that I/R injury decreased the proliferation and migration and promoted the apoptosis of HUVECs, and propofol restored the normal biological functions to HUVECs. I/R injury inhibited the expression of SUMO2/3 in HUVECs, and propofol increased the expression of SUMO2/3 in HUVECs. Interference of SUMO2/3 expression suppressed the proliferation and migration, and promoted the apoptosis of HUVECs. Propofol exerted its protective effect on HUVECs via autophagy mediated by SUMO2/3 proteins. Beclin1 was modified by SUMO2/3 at the K26 site. SUMO modification of the K26 site in Beclin1 was involved in the regulation of autophagy of HUVECs, and K26R Beclin1 had reduced effect in activating autophagy of HUVECs compared with wild-type Beclin1. These results demonstrate that SUMO2/3 participates in regulating the protective effect of propofol on HUVECs. SUMO2/3 activates the autophagy activity of cells by modifying the K26 site of Beclin1, thus inhibiting I/R injury to vascular endothelial cells.

Because the linear motor feeding system always runs in complex working conditions for a long time, its performance and state transition have great randomness. Therefore, abnormal detection is particularly significant for predictive maintenance to promptly discover the running state degradation trend. Aiming at the problem that the abnormal samples of linear motor feed system are few and the samples have time-series features, a method of abnormal operation state detection of a linear motor feed system based on normal sample training was proposed, named GANomaly-LSTM. The method constructs an encoding-decoding-reconstructed encoding network model. Firstly, the time-series features of vibration, current and composite data samples are extracted by the long short-term memory (LSTM) network; Secondly, the three-layer fully connected layer is employed to extract potential feature vectors; Finally, anomaly detection of the system is completed by comparing the potential feature vectors of the two encodings. An experimental platform of the X-Y two-axis linkage linear motor feeding system is built to verify the rationality of the proposed method. Compared with other classical methods such as GANomaly and GAN-AE, the average AUROC index of this method is improved by 17.5% and 9.3%, the average accuracy is enhanced by 11.6% and 15.5%, and the detection time is shortened by 223 ms and 284 ms, respectively. GANomaly-LSTM has successfully proved its superiority for abnormal detection for running state of linear motor feeding systems.

This study aimed to detetct Mycoplasma bovis (M. bovis) in bovine milk quickly and directly by developing and validating isothermal recombinase polymerase amplification (RPA) assays. Targeting the uvrC gene of M. bovis, an RPA assay based on the fluorescence monitoring (real-time RPA) and an RPA assay combined with a lateral flow strip (LFS RPA) were conducted. It took 20 min for the real-time RPA to finish in a Genie III at 39°C, and 15 min were required to perform the LFS RPA in an incubator block at 39°C, followed by the visualization of the products on the lateral flow strip within 5 min. Both of the two assays showed high specificity for M. bovis without any cross-reaction with the other tested pathogens. With the standard recombinant plasmid pMbovis-uvrC serving as a template, both RPA assays had a limit of detcion of 1.0 × 101 copies per reaction, equivalent to that of a real-time PCR assay. In the 65 milk samples collected from cattle with mastitis, the M. bovis genomic DNA was detected in 24 samples by both the real-time RPA and the LFS RPA assays. The developed RPA assays could detect M. bovis in bovine milk in an efficient, convenient, and credible manner as attractive and promising tools, and the assays would be helpful in the rapid response to M. bovis infection causing bovine mastitis.

Advanced oxidation process (AOP), with a high oxidation efficiency, fast reaction speed (relatively no secondary pollution), has become one of the core technologies of industrial wastewater and advanced drinking water treatment. Heterogeneous Fenton-like oxidation process (HFOP) is a kind of AOP, which developed rapidly in recent years in such a way to overcome the disadvantages of traditional Fenton reaction. Metal-organic frameworks (MOFs) and their derivatives become essential heterogeneous catalysts for organics mineralization due to the large specific surface area, abundant active sites, and ease of structural regulation. However, the knowledge gap on the mechanism and the fate of heterogeneous catalyst species during organics degradation activities by MOFs presents considerable impediments, particularly for a wide application and scaling up the process. This work has the potential to provide guidance and ideas for researchers and engineers in the fields of environmental remediation, environmental catalysis and functional materials. This review focuses on clarifying the critical mechanism of •OH production from MOFs and derivatives as well as its action on the organic’s degradation process. The recent developments in MOF based HFOP are compared, and more attention is paid for the following aspects in this review: (1) classifies systematically progressive modification methods of MOFs by chemical and physical treatments; (2) analyzes the fate of catalytic species during treating organic wastewater; (3) proposes design ideas and principles for improving the performance of MOFs catalysts; (4) discusses the main factors influencing the catalytic properties and practical application; (5) summarizes the possible research challenges and directions for MOFs and their derivatives as catalysts applied to wastewater treatment in the future.

Abstract Background Foot-and-mouth disease (FMD), which is caused by foot-and-mouth disease virus (FMDV), is a highly contagious tansboundary disease of cloven-hoofed animals and causes devastating economic damages. Accurate, rapid and simple detection of FMDV is critical to containing an FMD outbreak. Recombinase polymerase amplification (RPA) has been explored for detection of diverse pathogens because of its accuracy, rapidness and simplicity. A visible and equipment-free reverse-transcription recombinase polymerase amplification assay combined with lateral flow strip (LFS RT-RPA) was developed to detect the FMDV using primers and LF probe specific for the 3D gene. Results The FMDV LFS RT-RPA assay was performed successfully in a closed fist using body heat for 15 min, and the products were visible on the LFS inspected by the naked eyes within 2 min. The assay could detect FMDV serotypes O, A and Asia1, and there were no cross-reactions with vesicular stomatitis virus (VSV), encephalomyocarditis virus (EMCV), classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus 2 (PCV2) and pseudorabies virus (PRV). The analytical sensitivity was 1.0 × 102 copies in vitro transcribed FMDV RNA per reaction, which was the same as a real-time RT-PCR. For the 55 samples, FMDV RNA positive rate was 45.5% (25/55) by LFS RT-RPA and 52.7% (29/55) by real-time RT-PCR. For the LFS RT-RPA assay, the positive and negative predicative values were 100% and 80%, respectively. Conclusions The performance of the LFS RT-RPA assay was comparable to real-time RT-PCR, while the LFS RT-RPA assay was much faster and easier to be performed. The developed FMDV LFS RT-RPA assay provides an attractive and promising tool for rapid and reliable detection of FMDV in under-equipped laboratory and at point-of-need facility, which is of great significance in FMD control in low resource settings.

Abstract Background Canine parvovirus 2, a linear single-stranded DNA virus belonging to the genus Parvovirus within the family Parvoviridae, is a highly contagious pathogen of domestic dogs and several wild canidae species. Early detection of canine parvovirus (CPV-2) is crucial to initiating appropriate outbreak control strategies. Recombinase polymerase amplification (RPA), a novel isothermal gene amplification technique, has been developed for the molecular detection of diverse pathogens. In this study, a real-time RPA assay was developed for the detection of CPV-2 using primers and an exo probe targeting the CPV-2 nucleocapsid protein gene. Results The real-time RPA assay was performed successfully at 38 °C, and the results were obtained within 4–12 min for 105–101 molecules of template DNA. The assay only detected CPV-2, and did not show cross-detection of other viral pathogens, demonstrating a high level of specificity. The analytical sensitivity of the real-time RPA was 101 copies/reaction of a standard DNA template, which was 10 times more sensitive than the common RPA method. The clinical sensitivity of the real-time RPA assay matched 100% (n = 91) to the real-time PCR results. Conclusion The real-time RPA assay is a simple, rapid, reliable and affordable method that can potentially be applied for the detection of CPV-2 in the research laboratory and point-of-care diagnosis.

Abstract Background Canine distemper, caused by Canine distemper virus (CDV), is a highly contagious and fatal systemic disease in free-living and captive carnivores worldwide. Recombinase polymerase amplification (RPA), as an isothermal gene amplification technique, has been explored for the molecular detection of diverse pathogens. Methods A real-time reverse transcription RPA (RT-RPA) assay for the detection of canine distemper virus (CDV) using primers and exo probe targeting the CDV nucleocapsid protein gene was developed. A series of other viruses were tested by the RT-RPA.Thirty-two field samples were further tested by RT-RPA, and the resuts were compared with those obtained by the real-time RT-PCR. Results The RT-RPA assay was performed successfully at 40 °C, and the results were obtained within 3 min–12 min. The assay could detect CDV, but did not show cross-detection of canine parvovirus-2 (CPV-2), canine coronavirus (CCoV), canine parainfluenza virus (CPIV), pseudorabies virus (PRV) or Newcastle disease virus (NDV), demonstrating high specificity. The analytical sensitivity of RT-RPA was 31.8 copies in vitro transcribed CDV RNA, which is 10 times lower than the real-time RT-PCR. The assay performance was validated by testing 32 field samples and compared to real-time RT-PCR. The results indicated an excellent correlation between RT-RPA and a reference real-time RT-PCR method. Both assays provided the same results, and R2 value of the positive results was 0.947. Conclusions The results demonstrated that the RT-RPA assay offers an alternative tool for simple, rapid, and reliable detection of CDV both in the laboratory and point-of-care facility, especially in the resource-limited settings.

This study examined the mediating effects of cognitive empathy and affective empathy in the relationship between dispositional awe and prosocial behaviour in medical students, and whether perceived stress moderated this association. A total of 631 medical students from two medical tertiary institutions in Liaoning Province, China, participated in this survey. The findings revealed that (1) dispositional awe was positively associated with prosocial behaviour; (2) the positive association between dispositional awe and prosocial behaviour was partially mediated by cognitive empathy and affective empathy; (3) perceived stress significantly attenuated the association between dispositional awe and cognitive empathy, and the association between cognitive empathy and prosocial behaviour. The findings yield practical implications for the improvement strategies of prosocial behaviour among medical students and provide suggestions for future educational interventions.

Most online tool condition monitoring (TCM) methods easily cause machining interference. To solve this problem, we propose a method based on the analysis of the spindle motor current signal of a machine tool. Firstly, cutting experiments under multi-conditions were carried out at a Fanuc vertical machining center, using the Fanuc Servo Guide software to obtain the spindle motor current data of the built-in current sensor of the machine tool, which can not only apply to the actual processing conditions but, also, save costs. Secondly, we propose the variational mode decomposition (VMD) algorithm for feature extraction, which can describe the tool conditions under different cutting conditions due to its excellent performance in processing the nonstationary current signal. In contrast with the popular wavelet packet decomposition (WPD) method, the VMD method was verified as a more effective signal-processing technique according to the experimental results. Thirdly, the most indicative features that relate to the tool condition were fed into the ensemble learning (EL) classifier to establish a nonlinear mapping relationship between the features and the tool wear level. Compared with existing TCM methods based on current sensor signals, the operation process and experimental results show that using the proposed method for the monitoring signal acquisition is suitable for the actual processing conditions, and the established tool wear prediction model has better performance in both accuracy and robustness due to its good generalization capability.

In this paper we investigated the microstructure and phase transition of atomized Fe-(1.3, 7.9, 11.7 wt.%) Mn alloy powders. The results show that the main phases of Fe-1.3Mn, Fe-7.9Mn and Fe-11.7Mn powders are ferrite, α’-martensite+austenite, α’-martensite+ε-martensite+austenite, respectively. The δ-ferrite in the Fe-1.3Mn powder is the high-temperature δ-ferrite directly formed from liquid, companying by a small number of nanometer sized austenite particles precipitated from the ferrite matrix. In the Fe-11.7Mn powder, the γ-austenite, ε-martensite and α’-martensite are found in the same region and have the K-S orientation relationship, suggesting phase transitions of γ-austenite → ε-martensite → α’-martensite and γ → α’-martensite.

Feline herpesvirus 1 (FHV-1), an enveloped dsDNA virus, is one of the major pathogens of feline upper respiratory tract disease (URTD) and ocular disease. Currently, polymerase chain reaction (PCR) remains the gold standard diagnostic tool for FHV-1 infection but is relatively expensive, requires well-equipped laboratories and is not suitable for field tests. Recombinase polymerase amplification (RPA), an isothermal gene amplification technology, has been explored for the molecular diagnosis of infectious diseases. In this study, an exo-RPA assay for FHV-1 detection was developed and validated. Primers targeting specifically the thymidine kinase (TK) gene of FHV-1 were designed. The RPA reaction was performed successfully at 39°C and the results were obtained within 20 min. Using different copy numbers of recombinant plasmid DNA that contains the TK gene as template, we showed the detection limit of exo-RPA was 102 copies DNA/reaction, the same as that of real time PCR. The exo-RPA assay did not cross-detect feline panleukopenia virus, feline calicivirus, bovine herpesvirus-1, pseudorabies virus or chlamydia psittaci, a panel of pathogens important in feline URTD or other viruses in Alphaherpesvirinae, demonstrating high specificity. The assay was validated by testing 120 nasal and ocular conjunctival swabs of cats, and the results were compared with those obtained with real-time PCR. Both assays provided the same testing results in the clinical samples. Compared with real time PCR, the exo-RPA assay uses less-complex equipment that is portable and the reaction is completed much faster. Additionally, commercial RPA reagents in vacuum-sealed pouches can tolerate temperatures up to room temperature for days without loss of activity, suitable for shipment and storage for field tests. Taken together, the exo-RPA assay is a simple, fast and cost-effective alternative to real time PCR, suitable for use in less advanced laboratories and for field detection of FHV-1 infection.