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Background: Chicken coccidiosis is a protozoan disease that leads to considerable economic losses in the poultry industry. Live oocyst vaccination is currently the most effective measure for the prevention of coccidiosis. However, it provides limited protection with several drawbacks, such as poor immunological protection and potential reversion to virulence. Therefore, the development of effective and safe vaccines against chicken coccidiosis is still urgently needed. Methods: In this study, a novel oral vaccine against Eimeria tenella was developed by constructing a recombinant Lactobacillus plantarum (NC8) strain expressing the E. tenella RON2 protein. We administered recombinant L. plantarum orally at 3, 4 and 5 days of age and again at 17, 18 and 19 days of age. Meanwhile, each chick in the commercial vaccine group was immunized with 3 × 102 live oocysts of coccidia. A total of 5 × 104 sporulated oocysts of E. tenella were inoculated in each chicken at 30 days. Then, the immunoprotection effect was evaluated after E. tenella infection. Results: The results showed that the proportion of CD4+ and CD8+ T cells, the proliferative ability of spleen lymphocytes, inflammatory cytokine levels and specific antibody titers of chicks immunized with recombinant L. plantarum were significantly increased (P < 0.05). The relative body weight gains were increased and the number of oocysts per gram (OPG) was decreased after E. tenella challenge. Moreover, the lesion scores and histopathological cecum sections showed that recombinant L. plantarum can significantly relieve pathological damage in the cecum. The ACI was 170.89 in the recombinant L. plantarum group, which was higher than the 150.14 in the commercial vaccine group. Conclusions: These above results indicate that L. plantarum expressing RON2 improved humoral and cellular immunity and enhanced immunoprotection against E. tenella. The protective efficacy was superior to that of vaccination with the commercial live oocyst vaccine. This study suggests that recombinant L. plantarum expressing the RON2 protein provides a promising strategy for vaccine development against coccidiosis. [ABSTRACT FROM AUTHOR]

The dispersion of respiratory droplets is strongly influenced by the complex airflow induced by human activities, such as walking in a queue. Understanding the relationship between local airflow disturbances during queue walking and droplet dispersion is crucial. This study investigates the effects of following distance (1.0, 1.5, 2.0, and 2.5 m), walking speed (0.8, 1.0, 1.2, and 1.4 m/s), and droplet diameter (1, 10, 50, 80, and 120 μm) on droplet dispersion. The findings reveal that the interaction between wake vortex and forward airflow provides a foundation for cross-infection among individuals. An increased following distance leads to an initial rise and subsequent decrease in the concentration in the breathing zone of the susceptible individual. The social distances of 1.0 and 1.5 m are insufficient to mitigate the risk of cross-infection, warranting a recommended following distance of at least two meters. The effect of walking speed on droplet dispersion varies depending on the scenario. In cases involving standing and walking cycles, the infection risk of the susceptible individual gradually increases with higher walking speeds. Conversely, when individuals walk continuously in a queue, the infection risk of the susceptible individual decreases with increased walking speed. Moreover, intermediate-sized droplets play a critical role in the transmission of respiratory infectious diseases and demand heightened attention. This study expounds the intricate airflow dynamics during queue walking and emphasizes the significance of following distance, walking speed, and droplet diameter in minimizing the risk of cross-infection. [ABSTRACT FROM AUTHOR]

A variable geometry auxiliary inlet for a wide-body aircraft environmental control system with moveable deflectors operating in a large mass flow rate range is studied through numerical simulation and wind tunnel tests, which yields a design method for the variable geometry auxiliary inlet with high performance. The characteristics of the flow field are studied by numerical simulation. The results show that the favorable pressure gradient and the roll-up vortices are the major impetus that inhales the incoming flow into the inlet. The law of regulation and the performance variation under different conditions are obtained by wind tunnel test. The flow coefficient increases first but then decreases with the increase in the inlet opening, and the pressure rise ratio and total pressure recovery coefficient increase first and then decrease with the increase in the mass flow rate. In general, under the condition of a high Mach number (Ma > 0.4), the inlet opening of this test configuration should not exceed 50%. The deflectors can maintain the normal work of the environmental control system by moving properly to control the mass flow rate of the auxiliary inlet. [ABSTRACT FROM AUTHOR]

Enzymatic-based proximity labeling approaches based on activated esters or phenoxy radicals have been widely used for mapping subcellular proteome and protein interactors in living cells. However, activated esters are poorly reactive which leads to a wide labeling radius and phenoxy radicals generated by peroxide treatment may disturb redox-sensitive pathways. Herein, we report a photoactivation-dependent proximity labeling (PDPL) method designed by genetically attaching photosensitizer protein miniSOG to a protein of interest. Triggered by blue light and tunned by irradiation time, singlet oxygen is generated, thereafter enabling spatiotemporally-resolved aniline probe labeling of histidine residues. We demonstrate its high-fidelity through mapping of organelle-specific proteomes. Side-by-side comparison of PDPL with TurboID reveals more specific and deeper proteomic coverage by PDPL. We further apply PDPL to the disease-related transcriptional coactivator BRD4 and E3 ligase Parkin, and discover previously unknown interactors. Through over-expression screening, two unreported substrates Ssu72 and SNW1 are identified for Parkin, whose degradation processes are mediated by the ubiquitination-proteosome pathway. Methods to identify protein interaction networks often suffer from poor spatiotemporal resolution. Here the authors present a light-activated proximity labeling method where the protein of interest is fused to the photosensitizer protein miniSOG, allowing temporally resolved labeling of interactors. [ABSTRACT FROM AUTHOR]

Thermal fatigue caused by turbulent thermal mixing in tee pipes is always one of the failure factors of industrial pipes. At present, computational fluid dynamics (CFD) is still the main research method to study the thermal fatigue mechanism. Due to the limitations of the large eddy simulation (LES) model and the classical Reynolds Averaged Navier–Stokes (RANS) model in simulating thermal mixing, an advanced Embedded LES (ELES) model was developed. By comparing the model with data in the open literature, the validity of the ELES model to iso-thermal mixing was evaluated and proven. After that, the flow characteristics of the backflow upstream with different momentum ratios (MR) were studied using the ELES method, as well as the temperature characteristics near the wall where the backflow appears. It was found that the characteristics of the backflow and the temperature distribution upstream in the tee were different with different MR values and some regions under specified MR values are found to be more prone to thermal fatigue at the intersection of the tee upstream. Moreover, the frequency analysis at specified points near the wall under three different MR values was estimated to evaluate thermal fatigue and the results showed that long-period fluctuations of lower frequencies than 6 Hz upstream were observed. This work helps form a comprehensive understanding of the backflow in thermal mixing and the relationship between fatigue and backflow in the tee. [ABSTRACT FROM AUTHOR]

In this study, influence factors of liquid nitrogen spray cooling, including the parameters of the nozzle, the area of the heat sink, and the flow rate of liquid nitrogen, were investigated experimentally. On the basis of experimental data, experimental dimensionless correlations were obtained. It was shown that the error of correlation with only the Reynolds number (Re) and Prandtl number (Pr) was too low to predict the Nusselt number (Nu). With Re, Pr, the boiling number (Bg), and the Jacob number (Ja), while the error of correlation decreased, the experimental data deviated considerably from the fitting line by the correlation, which was still not suitable for prediction. The reasons for the experimental data's deviation were that the uniformity of the droplet distribution varied with the nozzle aperture, a change in the heat exchange area resulted in the formation of a local gas film, the droplet splash caused by a change in the flow rate influenced the heat exchange. The correlation obtained with Re, Pr, Bg, Ja, and the effective of spray mass flow flux η which was determined as the ratio of the liquid nitrogen mass flow rate involved in heat transfer to the uniform mass flow on the heat surface could be used to accurately predict Nu. [ABSTRACT FROM AUTHOR]

An experimental bench was constructed for liquid nitrogen spray cooling in an open loop system, and the combined effect of the spray height, heat sink surface diameter, and spray mass flow on the heat transfer characteristics of liquid nitrogen spray cooling was studied by comparing 50 sets of experimental data. In general, the heat transfer performance decreased with an increase in the spray height and heat sink surface diameter, with the latter's influence being more dominant. In the experiment, when the heat sink surface diameter increased to 24 mm, the influence of the spray height on the heat transfer performance decreased. The maximum critical heat flux and maximum heat transfer coefficient were 191.90 W·cm−2 and 16.67 W·cm−2·K−1. [ABSTRACT FROM AUTHOR]

The aero ball joint is pivotal in aircraft duct systems due to its favorable properties, including displacement compensation and flexibility. In the stress assessment of air ducts, ball joints are usually simplified by using "Joints" connections to reduce the convergence problems caused by non-linearity, which requires a high degree of accuracy in the characteristic parameters of the ball joint. Accordingly, this paper builds a high temperature and pressure fatigue test platform to investigate the bending characteristics of the ball joint at different temperatures and pressures and points out the limitations of the current method. Then, a method combining finite element analysis (FEA) and the BP neural network is proposed to obtain the characteristic parameters of the ball joint. The results showed that the bending process of the ball joint tended to have two typically different stiffness properties, which were high rigidity and low rigidity. The bending characteristics were strongly influenced by pressure, but less influenced by temperature. The existing test platform increased the force reaction at the contact areas of the ball joint, resulting in errors in the measurement of characteristic parameters. The BP neural network prediction method could effectively alter the ball joint properties and reduce errors. [ABSTRACT FROM AUTHOR]

COVID-19 is a respiratory infectious disease that spreads readily between people, and an urgent issue of passengers' exposure risk assessment in commercial aircraft has been raised because an aircraft cabin as a confined space may carry and transmit the disease worldwide. In this study, the droplets transmission process under different ventilation systems in a twin-aisle wide-body aircraft was studied using CFD simulations and the infection risk of passengers was assessed by the improved Wells–Riley model. Numerical results found that the transmission mechanism of droplets in the aircraft cabin was different depending on the type of ventilation systems and the location of the infectious source. Annular airflow could effectively enhance the ability of droplets transmission, while direct airflow, represented by displacement ventilation, could significantly inhibit droplets transmission. Accordingly, a new type of ventilation system was proposed based on the concept that the overall space is organized by annular airflow and the local area is direct airflow. Compared with sidewall mixing ventilation system, the infection risk of the new ventilation system presented in this study is reduced by 27%. [ABSTRACT FROM AUTHOR]

The type I interferon (IFN-I) signaling pathway is an important part of the innate immune response and plays a vital role in controlling and eliminating pathogens. African swine fever virus (ASFV) encodes various proteins to evade the host's natural immunity. However, the molecular mechanism by which the ASFV-encoded proteins inhibit interferon production remains poorly understood. In the present study, ASFV MGF360-11L inhibited cGAS, STING, TBK1, IKKε, IRF7 and IRF3-5D mediated activation of the IFN-β and ISRE promoters, accompanied by decreases in IFN-β, ISG15 and ISG56 mRNA expression. ASFV MGF360-11L interacted with TBK1 and IRF7, degrading TBK1 and IRF7 through the cysteine, ubiquitin–proteasome and autophagy pathways. Moreover, ASFV MGF360-11L also inhibited the phosphorylation of TBK1 and IRF3 stimulated by cGAS-STING overexpression. Truncation mutation analysis revealed that aa 167-353 of ASFV MGF360-11L could inhibit cGAS-STING-mediated activation of the IFN-β and ISRE promoters. Finally, the results indicated that ASFV MGF360-11L plays a significant role in inhibiting IL-1β, IL-6 and IFN-β production in PAM cells (PAMs) infected with ASFV. In short, these results demonstrated that ASFV MGF360-11L was involved in regulating IFN-I expression by negatively regulating the cGAS signaling pathway. In summary, this study preliminarily clarified the molecular mechanism by which the ASFV MGF360-11L protein antagonizes IFN-I-mediated antiviral activity, which will help to provide new strategies for the treatment and prevention of ASF. [ABSTRACT FROM AUTHOR]

It is important to optimize the structure of inlet due to the increasing demand of ram air. In this paper, structural optimization of the submerged inlet is pursued using a hybrid model by integrating least squares support vector machines (LS-SVM) prediction model and improved genetic algorithm-particle swarm optimization (GA-PSO). Inlet shape is controlled by changing three-dimensional geometric parameters. Ramp angle, width to depth ratio and ramp length play significant parts in this optimization process. Ram efficiency and mass flow are the main objectives of the performance evaluation. Results show that the prediction error of the mass flow and ram efficiency is 2.31% and 0.54%, respectively. Comparison with the original geometry is used to prove the optimization capabilities of the proposed optimization method. The mass flow and ram efficiency are increased by 29.2% and 10.0%, respectively. In addition, the characteristics of the optimized submerged inlet geometry are numerically investigated. The numerical results are compared to the optimization results and indicate that this optimization method has high validity. The error of ram efficiency and mass flow is 0.30% and 0.66%, respectively. Consequently, this optimization method can be valuable to aircraft engineers-by providing a novel approach for the design of the submerged inlet. [ABSTRACT FROM AUTHOR]

Some protozoa (Plasmodium falciparum, Toxoplasma gondii, etc) are used to treat cancer because they can improve tumour‐induced immunosuppression. This study aims to evaluate the antitumour effect of Eimeria stiedae oocyst soluble protein (ESSP). ESSP was extracted, and mice were injected with 5 × 105 CT26 cells in the right axilla, and then, 50 μg of ESSP was intraperitoneally injected for 5 continuous days. The effect of ESSP on tumour immunity was detected by flow cytometry 25 days after the CT26 inoculation. The results showed that ESSP can inhibit the growth of CT26 subcutaneous tumours; significantly increase the expression of MHC I, MHC II, CD80 and CD86 on the surface of splenic dendritic cells; and enhance the level of IL‐12 secretion. ESSP induced an increase in the number of NK cells in the mouse spleen, and the levels of IFN‐γ and CD107 were upregulated in the NK cells and CD8+ T cells. The number of metastatic nodules in the lung tumours in the mice was significantly reduced, and the number of tubes, area of the loops and total length of the tubes were significantly reduced. ESSP enhances the antitumour immune response and inhibits tumour growth, metastasis and angiogenesis. [ABSTRACT FROM AUTHOR]

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In recent years, the problem of heat dissipation in airborne directed energy weapons has attracted considerable research interest. Spray cooling can be applied to cool airborne directed energy weapons, owing to its several advantages such as a large heat transfer coefficient, absence of boiling hysteresis and uniform surface temperature. To examine the potential of an airborne spray cooling system, the typical high heat flux dissipation methods were compared, and the state of the art research on spray cooling was reviewed. This review was focused on studies related to the spray cooling hydrodynamic mechanism, experimental studies of closed loop spray cooling, numerical simulation studies about spray cooling and the identification of the factors influencing spray cooling systems, and investigations related to the multiple nozzle spray cooling technology and heat transfer correlation predictions. Overall, there is a need for further research to investigate the failure phenomenon after the critical state, matching operation of the total system and microscopic characteristics of airborne specific parameters. [ABSTRACT FROM AUTHOR]

Forced convection heat transfer is a significant factor for the thermal control of a stratospheric airship. However, most of researches were conducted without considering the influence of flight state causing serious errors. In order to accurately predict the forced convection heat transfer of the stratospheric airship at an angle of attack, firstly, an empirical correlation of Nusselt number (Nu) as function of Reynolds number (Re) andlength to diameter ratio (e) is developedunder horizontal state based on a validated computational fluid dynamic (CFD) method. Then, a correction factor K, considering its angle of attack (α), is proposed to modify this correlation. The results show that: (1) Nusselt number increases with the increase of Reynolds number, decreases as the length to diameter ratio changes from 2 ~ 6, and increases as the angle of attack changes from 0° ~ 20°. (2) At higher Reynolds number, the calculated results are 30 percent higher than those of previous studies with α = 20°. (3) Compared with α and e, the effect of Re on correction factor K can be ignored, and K is a strong equation of α and e. The efficiency of heat transfer is increased by 6 percent with α = 20°. The findings of this paper provide a technical reference for the thermal control of a stratospheric airship. [ABSTRACT FROM AUTHOR]

Background: Avian coccidiosis posts a severe threat to poultry production. In addition to commercial attenuated vaccines, other strategies to combat coccidiosis are urgently needed. Lactobacillus plantarum has been frequently used for expression of foreign proteins as an oral vaccine delivery system using traditional erythromycin resistance gene (erm). However, antibiotic selection markers were often used during protein expression and they pose a risk of transferring antibiotic resistance genes to the environment, and significantly restricting the application in field production. Therefore, a food-grade recombinant L. plantarum vaccine candidate would dramatically improve its application potential in the poultry industry. Results: In this study, we firstly replaced the erythromycin resistance gene (erm) of the pLp_1261Inv-derived expression vector with a non-antibiotic, asd-alr fusion gene, yielding a series of non-antibiotic and reliable, food grade expression vectors. In addition, we designed a dual-expression vector that displayed two foreign proteins on the surface of L. plantarum using the anchoring sequences from either a truncated poly-γ-glutamic acid synthetase A (pgsA′) from Bacillus subtilis or the L. acidophilus surface layer protein (SlpA). EGFP and mCherry were used as marker proteins to evaluate the surface displayed properties of recombinant L. plantarum strains and were inspected by western blot, flow cytometry and fluorescence microscopy. To further determine its application as oral vaccine candidate, the AMA1 and EtMIC2 genes of E. tenella were anchored on the surface of L. plantarum strain. After oral immunization in chickens, the recombinant L. plantarum strain was able to induce antigen specific humoral, mucosal, and T cell-mediated immune responses, providing efficient protection against coccidiosis challenge. Conclusions: The novel constructed food grade recombinant L. plantarum strain with double surface displayed antigens provides a potential efficient oral vaccine candidate for coccidiosis. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate a novel means of treating piglet diarrhoea caused by enterotoxigenic Escherichia coli (ETEC) strain K88 using traditional Chinese medicine (TCM) fermented by selected probiotic strains. Six types of TCMs were determined to be efficient at inhibiting ETEC growth. In addition, two types of probiotics, Lactobacillus 0111 and 0115, were shown to be the most efficient at inhibiting ETEC. The results of studies with mice indicated that the administration of individual TCMs or probiotic strains increased the growth of mice to a different extent. Specifically, the fermentation of Fructus mume, Galla chinensis and Herba taraxaci by the Lactobacillus 0111 strain enhanced their antibacterial ability compared with traditional Jade screen, possibly due to the presence of a compound producing an absorption peak with a retention time of 19.5 min by HPLC. The fermentation of TCMs by probiotic strain provides a novel approach to relieve the effects of the ETEC strain K88. [ABSTRACT FROM AUTHOR]

Necrotic enteritis is an economically important poultry disease caused by the bacterium Clostridium perfringens. There are currently no necrotic enteritis vaccines commercially available for use in broiler birds, the most important target population. Salmonella-vectored vaccines represent a convenient and effective option for controlling this disease. We used a single attenuated Salmonella vaccine strain, engineered to lyse within the host, to deliver up to three C. perfringens antigens. Two of the antigens were toxoids, based on C. perfringens α-toxin and NetB toxin. The third antigen was fructose-1,6-bisphosphate aldolase (Fba), a metabolic enzyme with an unknown role in virulence. Oral immunization with a single Salmonella vaccine strain producing either Fba, α-toxoid and NetB toxoid, or all three antigens, was immunogenic, inducing serum, cellular and mucosal responses against Salmonella and the vectored C. perfringens antigens. All three vaccine strains were partially protective against virulent C. perfringens challenge. The strains delivering Fba only or all three antigens provided the best protection. We also demonstrate that both toxins and Fba are present on the C. perfringens cell surface. The presence of Fba on the cell surface suggests that Fba may function as an adhesin. [ABSTRACT FROM AUTHOR]

Based on the study of the duct overheat detection system of civil aircraft in existence, its shortage is pointed out. Therefore a modified overheat detection system is designed with heat-sensitive property material and combinational circuits, which owns the capabilities of alarm and location for the high-temperature and pneumatic duct overheat part. Some interrelated optimization methods are put forward as well. Also, the overheat detection experiment platform is built and the designed detection system is validated experimentally. The influences of the overheat length and the response time of internal air temperature on the system are conducted. The research results show that the response time of the detection system decreases with the increase of temperature of the internal air and the response time remains approximately constant when the temperature reaches a certain value. Meanwhile the response time of the detection system decreases with the increase of overheat length. [ABSTRACT FROM AUTHOR]

Clostridium perfringens is an important Gram-positive pathogen responsible for food poisoning, necrotic enteritis, gas gangrene, and even death. Escherichia coli Nissle 1917 (EcN) is a well-characterized probiotic strain with demonstrated benefits. In this study, we evaluated the effects of EcN on growth, toxin production, biofilm formation, and inflammatory cytokine responses of C. perfringens. In vitro co-culture experiments demonstrated that EcN inhibited growth, gas production, and toxin production (α-toxin and NetB) of C. perfringens in a dose-dependent manner. The growth inhibition effect was not observed when C. perfringens was incubated with EcN cell-free supernatants (CFSE), suggesting that growth inhibition was caused by nutrition competition during co-incubation. In vitro studies demonstrated that pre-incubation with EcN did not inhibit C. perfringens attachment to Caco-2 cells, but did reduce C. perfringens total number, toxin production, and cytotoxicity after 24 h. The similar growth inhibition results were also observed during the formation of C. perfringens biofilm. Finally, pre-incubation of EcN with RAW264.7 cells significantly decreased the production of inflammatory cytokines caused by the introduction of C. perfringens. Our results indicate that EcN can inhibit many of the pathological effects of C. perfringens in vitro conditions. [ABSTRACT FROM AUTHOR]

In order to investigate the influence on heat transfer performance of heat pipe cold plate under vibration and acceleration conditions, ordinary copper-water heat pipe cold plate and micro-heat pipe array cold plate with different structures are chosen as the research objects, and the vibration test bed and acceleration test bed are established. The experimental results show that the Z-direction vibration and acceleration have the greater impact on heat transfer performance of the heat pipe cold plate than X-direction and Y-direction vibration and acceleration, but the effects of vibration can be ignored, and acceleration has more effect on micro-heat pipe array cold plate than on the double-U copper-water heat pipe cold plate. Also, the acceleration increase has little effect on the heat transfer characteristics of heat pipe cold plate. The double-U heat pipe cold plate has the best performance under vibration and acceleration conditions. [ABSTRACT FROM AUTHOR]

The classroom environment is of great significance for the health of primary and secondary school students, but a comfortable indoor environment often requires higher energy consumption. This paper presents a multi-objective optimization method based on an artificial neural network (ANN) model, which can help designers efficiently optimize the design of primary and secondary school classrooms in southern China. In this optimization method, first, the optimization objectives and variables are determined according to building characteristics, and the physical model is established through simulation software (EnergyPlus) to generate the sample space. Second, sensitivity analysis is carried out for each optimization variable, and the physical model is modified according to the results to regenerate the sample space. Third, the ANN model is trained by using the regenerated sample space, and the Pareto optimal solution is generated through the use of the non-dominated sorting genetic algorithm II (NSGA-II). Finally, the effectiveness of the multi-objective optimization method is proven through a typical case of primary and secondary school classrooms in Nanjing, China. The results show that, compared with the benchmark scheme, TES decreased by 810.8 kWh at most, PT increased by 47.8% at most and DI increased by 4.2% at most. [ABSTRACT FROM AUTHOR]

The Cre-recombinase mediated in vivo minicircle DNA vaccine platform (CRIM) provided a novel option to replace a traditional DNA vaccine. To further improve the immune response of our CRIM vaccine, we designed a dual promoter expression plasmid named pYL87 which could synthesize short HN protein under a prokaryotic in vivo promoter PpagC and full length HN protein of genotype VII Newcastle disease virus (NDV) under the previous eukaryotic CMV promoter at the same time. Making use of the self-lysed Salmonella strain as a delivery vesicle, chickens immunized with the pYL87 construction showed an increased serum haemagglutination inhibition antibody response, as well as an increased cell proliferation level and cellular IL-4 and IL-18 cytokines, compared with the previous CRIM vector pYL47. After the virus challenge, the pYL87 vector could provide 80% protection compared to 50% protection against genotype VII NDV in pYL47 immunized chickens, indicating a promising dual promoter strategy used in vaccine design. [ABSTRACT FROM AUTHOR]