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Objective To analyze the mechanism that Hcp1 protein in type Ⅵ secretion system of Burkholderia pseudomallei (B. pseudomallei) mediates the formation of multinucleated giant cells (MNGCs) when host cells are infected by the bacterium. Methods The mutant strain (BPC006 Δhcp1) and complementation strain (BPC006 Δhcp1:: hcp1) were constructed by homologous recombination and plasmid complement technology, respectively. After RAW264.7 cells were infected with B. pseudomallei, the localization of Hcp1 in host cells was analyzed by immunofluorescence staining. The localization was further verified by cytoplasmic-membrane isolation in 293T cells after transfecting pCDNA4.1-Hcp1. The biological significance and effect of Hcp1 were explored by the anti-Hcp1 polyclonal antibody blocking and the formation of MNGC was detected by Giemsa staining. Results Western blotting showed that BPC006 Δhcp1 could not express Hcp1, while BPC006 Δhcp1:: hcp1 restored Hcp1 expression. The above results proved that the mutant and complement strains were successfully constructed. Both cellular immunofluorescence co-localization and cytoplasmic-membrane isolation experiments showed that Hcp1 localized to host cell membranes. Last but not least, compared with the control group, anti-Hcp1 polyclonal antibodies inhibited the formation of MNGC (P < 0.01). Conclusion Hcp1 protein in type Ⅵ secretion system of B. pseudomallei is able to translocate to the RAW264.7 cell membranes and plays an important role in the formation of MNGCs.

Abstract Purpose Percutaneous transhepatic one-step biliary fistulation (PTOBF) is used to treat choledocholithiasis and biliary stricture. This study aimed to evaluate the safety and efficacy of ultrasound-guided PTOBF combined with rigid choledochoscopy in the treatment of recurrent hepatolithiasis. Materials and methods The clinical data of 37 consecutive patients who underwent PTOBF combined with rigid choledochoscopy for RHL from March 2020 to March 2022 at our hospital were retrospectively analyzed. Results A total of 68 percutaneous transhepatic punctures were performed in 37 patients, with a puncture success rate of 85.29% (58/68) and a dilatation success rate of 100.00% (58/58). The mean blood loss of operation was 9.84 ± 18.10 mL, the mean operation time was 82.05 ± 31.92 min, and the mean length of postoperative hospital stay was 5.59 ± 3.26 days. The initial stone clearance rate was 40.54% (15/37) and the final stone clearance rate was 100% (37/37). The incidence of postoperative complications was 10.81% (4/37), including 2 cases of pleural effusion, 1 case of hemorrhage, and 1 case of cholangitis, which recovered after treatment. During a mean follow-up period of 23 months (range 12 to 36 months), only 1 patient experienced stone recurrence. Conclusion Ultrasound-guided PTOBF combined with rigid choledochoscopy in the treatment of RHL based on skilful manipulation seems to be a safe, effective and minimally invasive method with clinical application value. Further comparative studies with large sample sizes are needed in the future to confirm the reliability of its therapeutic results.

Background: To compare the efficacy of Three-scope combined (laparoscopic, rigid choledochoscopy and electronic choledochoscopy, TS) with laparoscopic hepatectomy (LH) for patients with hepatolithiasis (HL). Methods: Between January 2019 and January 2020, 118 consecutive patients with HL treated with TS (TS group, n = 57) or LH (LH group, n = 61) were analyzed in this study. Perioperative and long-term outcomes, including operative time, intraoperative blood loss, blood transfusion, postoperative bowel function recovery time, postoperative hospital stay, complication rate, stone removal rate, and stone recurrence rate, were compared and analyzed between the two groups. Results: Compared with the LH group, the TS group had significantly lower intraoperative blood loss and transfusions, significantly shorter operative time and hospital stay, and fewer complications (P 0.05 for all). Conclusion: TS is a safe and effective treatment for HL and is superior to LH in terms of overall treatment outcome and complications.

Multi-UAV relay network can provide information relay and forwarding services for ground users who cannot communicate directly with the help of building reliable connectivity links. Software Defined Networking (SDN), a new network architecture, provides a promising solution for addressing problems such as load balancing, topology changes, and information sharing in multi-UAV relay network. Aiming at the load balancing problem of multi-UAV relay based on SDN, a dynamic migration algorithm based on load balancing and delay (DMA-LBD) is proposed by using the idea of dynamic migration. This ensures that users within the coverage area of UAVs with larger loads are migrated to other UAVs, thereby establishing new connection relationships that balance the load between all UAVs within the relay network. Experimental results demonstrated that, in comparison to other methods, the proposed algorithm makes a suitable compromise between the relay load balancing and the average delay of relay link. It can avoid the single optimization situation of an imbalanced UAV relay load or an excessive average delay, providing a more effective solution to the problem of relay load balancing of multi-UAV relay network.

By relaying messages between users, unmanned aerial vehicles (UAVs), which are frequently utilized in the communication industry, can be used as airborne communication relays to resolve connectivity problems. In order to effectively connect a large number of heterogeneous users dispersed on the ground, we deploy a large number of UAVs for reliable relay coverage and message transmission between users. We initially put forth a relay coverage algorithm that continuously optimizes the position of UAVs and the cell division of ground users in order to provide users with full coverage. Second, we study several relay message forwarding methods between UAVs while taking into account the features of heterogeneous users. A relay selection method, which takes the relay link throughput as the optimization goal, is proposed to ensure full connectivity between UAVs. Finally, we contrast and analyze how various relay forwarding methods affect the effectiveness of the relay network. The experimental results demonstrate that the proposed relay coverage algorithm can balance the UAV relay load better and reduce transmission delay, while the suggested relay selection strategy can minimize the number of isolated UAVs and maximize the throughput of UAV relay links.

Objective To construct the fluorescence-labeled Burkholderia pseudomallei (B. pseudomallei) to study the pathogenesis of the interaction between the bacteria and host cells. Methods Gene recombination technique was carried out to recombine the green fluorescent protein (GFP), red fluorescent protein (RFP) and blue fluorescent protein (BFP) genes into the prokaryotic expression vector pUCP28T, respectively, in order to obtain the fluorescence-labeled B. pseudomallei. Furthermore, the biological characteristics of fluorescence-labeled bacteria were detected in bacterial culture in vitro, and inflammatory factor IL-8 was detected to evaluate the changes in the ability of fluorescence-labeled bacteria infecting host cells. Then, the dynamic process of fluorescent-labeled B. pseudomallei being enveloped by host cell autophagosome was observed with aid of living cell workstation. Results Three fluorescence-labeled B. pseudomallei were constructed respectively, and were stably expressed in 20 passages in vitro. The expression of exogenous fluorescent proteins did not affect the growth of B. pseudomallei and infection of host cells. Meanwhile, the dynamic changes of co-localization between RFP-labeled B. pseudomallei and GFP-LC3 were observed by live cell imaging system. Conclusion Three different fluorescence-labeled B. pseudomallei are successfully constructed. And they are important practical tools for the pathogenesis of the bacteria and the screening of antimicrobial agents of melioidosis.

BackgroundThe kilowatt reactor using stirling technology (KRUSTY) is a heat-pipe-cooled reactor experimental system that uses a Stirling engine to convert thermal energy to electricity, it is the only one published experimental data for heat-pipe-cooled reactor systems. The KRUSTY experimental data under different working scenarios include the cold startup and load change processes, heat pipe failure, reactivity insertion, and heat sink loss.PurposeThis study aims to validate the self-developed system transient analysis code named TAPIRS-D for the heat-pipe-cooled reactor concept using KRUSTY experimental data.MethodsFirstly, an in-house system code for a heat-pipe-cooled reactor named TAPIRS-D was introduced, with the main theoretical module briefly explained, including the reactor power calculation module, heat transfer module for fuel assembly, and heat pipes. Then, the TAPIRS-D was applied for the first time to the simulation of the key processes of the KRUSTY prototypic reactor test under normal operation and accident conditions. Finally, comparison between the simulation data and experimental data was conducted for the validation of this analysis code.ResultsComparison results demonstrate that the maximum relative prediction error for the fuel temperature is less than 2%, and the reactor power average prediction error is less than 10%.ConclusionsThe prediction trend of the numerical simulation by TAPIRS-D fits well with the experimental data on key parameters such as core power and the temperature of fuel and heat pipes, which indicates that TAPIRS-D is well developed and is capable of conducting safety analysis for heat pipe cooled reactor concepts. The validation of this system analysis code provides a good reference for other newly developed system codes for heat pipe reactors.

BackgroundLoss of Coolant Accidents (LOCAs) is a crucial research topic for nuclear reactor safety analysis, and understanding the thermal–hydraulic behavior of the rod bundle channels during the reflooding stage of a LOCA is essential.PurposeThis study aims to develop theoretical models of the reflooding stage in addition to providing benchmark data for evaluating the safety analysis code for LOCAs in a reactor and for the design of the residual heat removal system.MethodsA series of bottom reflooding tests were conducted on a 5×5 rod bundle in the film boiling test facility at the nuclear safety and operation laboratory (NUSOL) of Xi'an Jiaotong University using uniformly heated rods. The experimental results were analyzed in detail, and the surface parameters of the heated rod bundle were obtained by solving a one-dimensional transient inverse heat conduction problem. The effects of different experimental conditions on the velocity of the quench front propagation were investigated. Furthermore, the experimental results were compared and calculated using the thermal safety analysis code, and the problems with the thermal safety analysis code RELAP5 reflooding simulation are summarized.ResultsOur results indicate that a high inlet flow rate, high inlet subcooling degree, and low power density are favorable for the propagation of the cold front during the reflooding process. Additionally, the root mean square (RMS) error of the simulated quench time and peak cladding temperature (PCT) are 40.994 s and 61.465 K, respectively. However, the simulation results have a relatively large error compared with the experimental results in the post-critical heat flux (CHF) heat transfer stage, primarily owing to the issues with the boiling mode judgment and membrane boiling heat transfer model.ConclusionsThe experimental data of this study can serve as new verification data for flow and heat transfer prediction models during the reflooding process; it can also be used to evaluate and optimize the thermal-hydraulic safety analysis code. Loss of Coolant Accidents (LOCAs) is a crucial research topic for nuclear reactor safety analysis, and understanding the thermal-hydraulic behavior of the rod bundle channels during the reflooding stage of a LOCA is essential.

High fluoride water is a crucial driving factor for endemic fluorosis. As an important research content of hydrogeochemistry, the enrichment of fluorine in alkaline water has received a fair amount of scholarly attention, but the understanding of the migration and enrichment of fluorine in acid mine drainage (AMD) in karst area remains very limited. An analysis of 13 consecutive periods of hydrochemical samples (312 samples in total) revealed that the weathering of carbonates and sulfide-rich coal measures induced a pH as low as 2.29 in the Chetian River in Jinsha, Southwest China. The highest content of fluorine in AMD was 23.8 mg/L, and the average content in the basin was 1.4 mg/L. In terms of the seasonal variation in the whole basin, the fluorine content were higher in the rainy season than in the dry season. The mineral saturation index shows that the dissolution of fluorapatite and fluorite is an important source of fluorine. The chloro-alkaline indices displayed a strong ion exchange process in the basin, promoting the release of fluorine in silicate minerals. In comparison, the contribution of external inputs, such as atmospheric deposition, was less. Additionally, evaporation was shown to have a limited influence on fluorine enrichment. Meanwhile, pH was an essential factor driving the dynamic transformation of the mode of occurrence of fluorine in water. In the upstream alkaline water, the main occurrence form of fluorine was free F−, while the F/Al ratio for most of the acidic samples was ≤ 1.0, indicating the main occurrence form of fluorine was likely AlF2+. The conclusion of this study provides a new understanding for deepening the geochemical characteristics of fluorine in karst surface water.

Edge computing provides off-load computing and application services close to end-users, greatly reducing cloud pressure and communication overhead. However, wireless edge networks still face the risk of network attacks. To ensure the security of wireless edge networks, we present Federated Learning-based Attention Gated Recurrent Unit (FedAGRU), an intrusion detection algorithm for wireless edge networks. FedAGRU differs from current centralized learning methods by updating universal learning models rather than directly sharing raw data among edge devices and a central server. We also apply the attention mechanism to increase the weight of important devices, by avoiding the upload of unimportant updates to the server, FedAGRU can greatly reduce communication overhead while ensuring learning convergence. Our experimental results show that, compared with other centralized learning algorithms, FedAGRU improves detection accuracy by approximately 8%. In addition, FedAGRU's communication cost is 70% less than other federated learning algorithms, and it exhibits strong robustness against poisoning attacks.

In the late stage of the ultra-high water cut development, the untabulated reservoir (not included in the submitted reserve sheet) is considered an important part of production sustainability in the X oilfield. According to the coring well data of 5 wells in the eastern district, the untabulated reservoir is associated with higher heterogeneity. Specifically, it develops not only the conventional low and ultra-low permeability sands but also medium-high permeability sands with thickness below 0.2 m. Given this, the research investigates the sedimentary models, spatial distribution, and heterogeneity of the different types of untabulated sand bodies, based on the core analysis. Moreover, the physical model water flooding experiments are carried out and the production characteristics of the different sand bodies in the untabulated reservoir with the different recovery approaches are clarified. The findings of this research effectively solve the development contradictions of the untabulated reservoir and lay down the foundation for the further potential tapping of the untabulated reservoir.

An automotive seat is a key component which not only provides restraint and support for its occupant, but also mitigates vibration. Since an automotive seat is in constant contact with the vehicle occupant, its dynamic comfort is of great importance in automotive seat designs. In this study, three automotive seats with different foam firmnesses were evaluated to understand how the foam firmness, through different foam formulations, affected the seat vibration performance and perceived dynamic comfort in a laboratory (study 1) and field setting (study 2). In a repeated-measures laboratory based study, whole-body vibration (per ISO 2631-1), self-reported body discomfort, and seating comfort were measured and compared among the three automotive seats while participants were exposed to tri-axial, field-measured, automotive vibration and X-Y-Z axis 1–30 Hz sine sweeps. In a subsequent ride-and-drive field study, the two seats that received the highest comfort ratings from the laboratory study were installed in two identical vehicles and whole body vibration (WBV) and self-reported seating comfort were evaluated by the participants. The results showed that the foam firmness significantly affected WBV measures and self-reported comfort (p < 0.05). This study demonstrated that altering foam formulation can be an effective way of further improving dynamic vibration and seat comfort performance.

Objective The current study investigated the effect of c-Jun NH2-terminal kinase (JNK) expression on the growth of transplanted breast cancer tumors in mice. Methods A breast cancer transplantation model was established in BALB/c mice, which were then treated with SP600125 (30 mg/kg) for 24 days. After sacrificing the mice, the inhibitory effects of SP600125 on breast cancer growth were calculated by weighing tumors. Moreover, vascular endothelial growth factor (VEGF) expression and the tumor microvascular density (MVD) were evaluated via immunohistochemistry. Cell apoptosis was also examined using a TUNEL kit. Results Compared with the findings in the control group, SP600125 treatment (30 mg/kg) obviously suppressed tumor growth during the 15-day observation period. SP600125 treatment markedly inhibited JNK mRNA expression. Furthermore, VEGF protein expression (50% vs. 100%) and MVD (18.27 ± 1.70 vs. 23.17 ± 4.02) were also significantly decreased by SP600125 treatment, whereas the apoptosis index was significantly higher in the treatment group (10.23 ± 1.97% vs. 4.53 ± 1.40%). Conclusion Inhibition of JNK signaling can significantly suppress the growth of transplanted breast tumors in mice.

Venous ulcers are chronic transcutaneous wounds common in the lower legs. They are resistant to healing and have a 78% chance of recurrence within 2 years. It is commonly accepted that venous ulcers are caused by the insufficiency of the calf muscle pump, leading to blood pooling in the lower legs, resulting in inflammation, skin oedema, tissue necrosis and eventually skin ulceration. However, the detailed physiological events by which inflammation contributes to wound formation are poorly understood. We therefore sought to develop a model that simulated the inflammation, using it to determine the internal stresses and pressure on the skin that contribute to venous ulcer formation. A three-layer finite-element skin model (epidermis, dermis and hypodermis) was developed to explore the roles in wound formation of two inflammation identifiers: glycosaminoglycans (GAG) and sodium. A series of parametric studies showed that increased GAG and sodium content led to oedema and increased tissue stresses of 1.5 MPa, which was within the reported range of skin tissue ultimate tensile stress (0.1–40 MPa). These results suggested that both the oedema and increased fluid pressure could reach a threshold for tissue damage and eventual ulcer formation. The models presented here provide insights to the pathological events associated with venous insufficiency, including inflammation, oedema and skin ulceration.

OBJECTIVES:The goal of this research was to evaluate how material curl, package structure and handling of pouches containing medical devices affect rates of contact between non-sterile surfaces and sterile devices during aseptic transfer. METHODS:One hundred and thirty-six individuals with practical experience in aseptic technique were recruited. Participants were asked to present the contents of four different pouch designs (a standard, one designed to curl in, another to curl out and one that incorporated a tab) using two transfer techniques. During the first block of trials "standard technique" was used; participants presented using their typical methods to the sterile field. Trials in the second block employed "modified technique"; participants were instructed to grab the package at the top center and present package contents using a single, fluid motion. The outside of the pouch and the backs of the participants' hands were coated using a simulated contaminant before each trial. The simulant was undetectable in the visible spectrum, but fluoresced under a black light. The dependent variable was recorded in a binary fashion and analyzed using a generalized linear mixed model. RESULTS:Participants were between 20-57 and the averaged year 5.1 years of experience in aseptic technique. The data analysis was based on generalized linear mixed effects (GLMM) model, which accommodates the repeated measurements within the same participant. The effect of the pouch design was significant (P‹0.001), but the effect of aseptic technique did not suggest significance (P = 0.088). Specifically, pouches designed with the material curled outward resulted in significantly fewer contacts with non-sterile surfaces than the other styles, including the inward, tab, and standard styles; this was true regardless of the used aseptic technique, standard (P = 0.0171, P = 0.0466, P = 0.0061, respectively) or modified (P‹0.0001 for all comparisons)). CONCLUSION:Results presented here contribute to a growing body of knowledge that investigates packaging as a potential route of contamination for sterile devices during aseptic presentation. Specifically, we provide insights regarding how both package design and opening technique can be informed in ways that build safety into the healthcare system.

An important task in facilitating the development of thermally conducting graphene/polymer nanocomposites is to suppress the intrinsically strong intersheet π-π stacking of graphene, and thereby to improve the exfoliation and dispersion of graphene in the matrix. Here, a pre-programmed intercalation approach to realize the in situ growth of graphene nanosheets at the inorganic template is demonstrated. Specifically, microsized MgO granules with controlled geometrical size were synthesized using a precipitation method, allowing the simultaneous realization of high surface activity. In the presence of a carbon and nitrogen source, the MgO granules were ready to induce the formation of graphene nanosheets (G@MgO), which allowed for the creation of tenacious linkages between graphene and template. More importantly, the incorporation of G@MgO into polymer composites largely pushed up the thermal conductivity, climbing from 0.39 W/m∙K for pristine polyethylene to 8.64 W/m∙K for polyethylene/G@MgO (60/40). This was accompanied by the simultaneous promotion of mechanical properties (tensile strength of around 30 MPa until 40 wt % addition of G@MgO), in contrast to the noteworthy decline of tensile strength for MgO-filled composites with over 20 wt.% fillers.