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The dengue virus, the primary cause of dengue fever, dengue hemorrhagic fever, and dengue shock syndrome, is the most widespread mosquito-borne virus worldwide. In recent decades, the prevalence of dengue fever has increased markedly, presenting substantial public health challenges. Consequently, the development of an efficacious vaccine against dengue remains a critical goal for mitigating its spread. Our research utilized Celcradle™, an innovative tidal bioreactor optimized for high-density cell cultures, to grow Vero cells for dengue virus production. By maintaining optimal pH levels (7.0 to 7.4) and glucose concentrations (1.5 g/L to 3.5 g/L) during the proliferation of cells and viruses, we achieved a peak Vero cell count of approximately 2.46 × 109, nearly ten times the initial count. The use of Celcradle™ substantially decreased the time required for cell yield and virus production compared to conventional Petri dish methods. Moreover, our evaluation of the immunogenicity of the Celcradle™-produced inactivated DENV4 through immunization of mice revealed that sera from these mice demonstrated cross-reactivity with DENV4 cultured in Petri dishes and showed elevated antibody titers compared to those from mice immunized with virus from Petri dishes. These results indicate that the dengue virus cultivated using the Celcradle™ system exhibited enhanced immunogenicity relative to that produced in traditional methods. In conclusion, our study highlights the potential of the Celcradle™ bioreactor for large-scale production of inactivated dengue virus vaccines, offering significant promise for reducing the global impact of dengue virus infections and accelerating the development of effective vaccination strategies.

A 2 μm wavelength band spot size converter (SSC) based on a trident structure is proposed, which is coupled to a lensed fiber with a mode field diameter of 5 μm. The cross-section of the first segment of the tapered waveguide structure in the trident structure is designed as a right-angled trapezoidal shape, which can further improve the performance of the SSC. The coupling loss of the SSC is less than 0.9 dB in the wavelength range of 1.95~2.05 μm simulated by FDTD. According to the experimental results, the lowest coupling loss of the SSC is 1.425 dB/facet at 2 μm, which is close to the simulation result. The device is compatible with the CMOS process and can provide a good reference for the development of 2 μm wavelength band integrated photonics.

Antibiotic resistance poses a significant threat to the public health domain. A favorable platform for generating and disseminating antibiotic-resistant genes (ARGs) and antibiotic-resistant bacteria (ARB) is provided by landscaped fish ponds created by urbanization. This research delved into the effects exerted by different concentrations of specific antibiotics, namely tetracycline and ciprofloxacin, on the microbial community composition present in water samples obtained from a landscape pond. Additionally, we analyzed the abundance of ARGs and the class 1 integron-integrase gene (intI1), and identified potential hosts of ARGs. The results indicated that the consistent administration of antibiotics significantly influenced the microbial community structure, resulting in variations within both bacterial communities and functionalities. Furthermore, the absolute quantities of ARGs, including tetA, tetC, qnrA, and qnrS, as well as the integrase gene intI1, exhibited augmentation in response to varying types and concentrations of antibiotics. Notably, the regular input of low concentrations of antibiotics produced higher levels of abundance of ARGs than the regular input of higher concentrations of antibiotics. The use of different types of antibiotics led to diverse host bacteria structures.

The integration of unmanned aerial vehicles (UAVs) and the Internet of Things (IoT) has opened up new possibilities in various industries. However, with the increasing number of Internet of Drones (IoD) networks, the risk of network attacks is also rising, making it increasingly difficult to identify malicious attacks on IoD systems. To improve the accuracy of intrusion detection for IoD and reduce the probability of false positives and false negatives, this paper proposes a Q-learning-based two-layer cooperative intrusion detection algorithm (Q-TCID). Specifically, Q-TCID employs an intelligent dynamic voting algorithm that optimizes multi-node collaborative intrusion detection strategies at the host level, effectively reducing the probability of false positives and false negatives in intrusion detection. Additionally, to further reduce energy consumption, an intelligent auditing algorithm is proposed to carry out system-level auditing of the host-level detections. Both algorithms employ Q-learning optimization strategies and interact with the external environment in their respective Markov decision processes, leading to close-to-optimal intrusion detection strategies. Simulation results demonstrate that the proposed Q-TCID algorithm optimizes the defense strategies of the IoD system, effectively prolongs the mean time to failure (MTTF) of the system, and significantly reduces the energy consumption of intrusion detection.

Integrating the graded index (GRIN) waveguide with the 2-D inversely-tapered waveguide, a new design of spot size converter (SSC) has been proposed to couple the light beam between the cleaved single-mode fiber (SMF) and the silicon (Si) wire waveguide on the silicon-on-insulator (SOI) platform. The device demonstrates a low coupling loss of 0.27 dB when it is coupled to a cleaved SMF. The polarization-dependent loss (PDL) is less than 0.25 dB, and the 1-dB alignment tolerance is about −2.0~2.0 µm for both vertical and horizontal directions. At the same time, the starting tip width of the tapered waveguide is kept at the level of the lithography limitation at the current commercial silicon photonics fab. This integrated SSC could be an improved design for reducing the coupling loss between the cleaved SMF and the Si waveguide.

Single Snorkel Furnace (SSF) vacuum refining furnace is a novel external refining equipment for high clean steel production. RH is a molten steel refining technology developed by Rheinstahl-Heraeus company. Compared with the traditional RH furnace, the SSF furnace has the advantages of a simple structure, high refining efficiency, and low production cost. However, because the upward flow and the downward flow are in a single snorkel, the flow phenomenon is more complex than that in the RH device. Therefore, the gas–liquid two-phase flow law in SSF furnaces plays an important role in improving equipment efficiency and accurate control. In addition, the evolution and movement behavior of bubbles have an important influence on the two-phase flow. In this study, the Population Balance Model (PBM) model is employed to study the bubble properties, taking into account the effect of bubble coalescence and breakup on the flow field. The simulation results with this model are consistent with the experimental values, and the comparison with the results of the model without the PBM is revealed to be closer with less error. The results show that with the PBM model the flow field is more homogeneously distributed, the flow velocity is more stable, and the area distribution of the upward flow and downward flow in the snorkel is more symmetrical. In the case of this study, as the fluid level rises, the bubble diameter will increase due to the decrease in hydrostatic pressure.

Gabion has been extensively used in retaining walls and slope protection. This study carries out a safety risk analysis of a new structure combining basalt fiber reinforcement (BFR) and the traditional gabion structure. The micro-parameters of BFR and soil were calibrated by using the 3D discrete element method after the tensile test of BFR was completed. The mechanical property of the gabion unit was investigated by using a refined model and a numerical test of uniaxial compression. This work developed a simplified method to simulate the seepage effect. The stress condition and sliding displacement between gabions were also investigated. Deformation, stress, and porosity were all used to evaluate the stability of the new type of gabion slope. According to this study, BFR has a tensile strength of 68.22 MPa, and the safety factor increased by 25.68% after using these BFR gabions. The damage is mainly manifested by bending the BFRs and the dislocation of the gabion units, as the slope does not slip. It is indicated this novel gabion structure has a lower safety risk compared to traditional ones, and thus can be popularized and used in retaining walls and slope protection.

A high-throughput layered decoder for quasi-cyclic (QC) low-density parity-check (LDPC) codes is required for communication systems. The preferred way to improve the throughput is to insert pipeline stages and increase the operating frequency, which suffers from pipeline conflicts at the same time. A priority-based layered schedule is proposed to keep the updates of log-likelihood ratios (LLRs) as frequent as possible when pipeline conflicts happen. To reduce pipeline conflicts, we also propose double update queues for layered decoders. The proposed double update queues improve the percentage of updated LLRs per iteration. Benefitting from these, the performance loss of the proposed decoder for the fifth generation (5G) new radio (NR) is reduced from 0.6 dB to 0.2 dB using the same quantization compared with the state-of-the-art work. As a result, the throughput of the proposed decoder improved up to 2.85 times when the signal-to-noise ratio (SNR) was equal to 5.9 dB.

At 2 µm wavelengths (149.9 THz), hollow-core photonics band gap fibers have higher light power damage thresholds, stable polarization states, and lower losses of 0.1 dB/km. Additionally, a thulium-doped fiber amplifier can provide a gain of >35 dB. Specifically, an indium-rich InGaAs photodetector shows a naturally higher photoresponsivity at 2 µm wavelengths than the C-band. Therefore, using tunable photo-generated microwave technology at 2 µm wavelengths could achieve higher photo-to-electric power conversion efficiencies for higher RF output power applications using the same method at the same frequency. Here, a double sideband with the carrier suppression modulation method was experimentally applied on 2 µm wavelengths to generate tunable and stable microwave carriers. Comparison experiments were also applied on the 1.55 µm (193.4 THz)/1.31 µm wavelengths (228.8 THz) based on the same indium-rich InGaAs photodetector. Through normalization on the wavelength-corresponded squared external quantum efficiency to visualize the photo-to-electric power conversion efficiency at different wavelengths under the same input optical signal power, the ratio between the results at 2 µm wavelengths and C/O-band is abstracted as 1.31/1.98, approaching theoretical estimations. This corresponds to a power conversion efficiency increasement of ~1.16 dB/~2.98 dB. To our knowledge, this is the first study on 2 micron wavelengths that proves the corresponding high efficiency power conversion property.

2D layered MXene (Ti3C2Tx) with high conductivity and pseudo-capacitance properties presents great application potential with regard to electrode materials for supercapacitors. However, the self-restacking and agglomeration phenomenon between Ti3C2Tx layers retards ion transfer and limits electrochemical performance improvement. In this study, a 3D porous structure of Ti3C2Tx was obtained by adding alkali to a Ti3C2Tx colloid, which was followed by flocculation. Alkaline-induced flocculation is simple and effective, can be completed within minutes, and provides 3D porous networks. As 3D porous network structures present larger surface areas and more active sites, ions transfer accelerates, which is crucial with regard to the improvement of the superior capacitance and rate performance of electrodes. The sample processed with KOH (K-a-Ti3C2Tx) exhibited a high capacity of approximately 300.2 F g−1 at the current density of 1 A g−1. The capacitance of the samples treated with NaOH and LiOH is low. In addition, annealing is essential to further improve the capacitive performance of Ti3C2Tx. After annealing at 400 °C for 2 h in a vacuum tube furnace, the sample treated with KOH (K-A-Ti3C2Tx) exhibited an excellent specific capacitance of approximately 400.7 F g−1 at a current density of 1 A g−1, which is considerably higher than that of pristine Ti3C2Tx (228.2 F g−1). Furthermore, after 5000 charge–discharge cycles, the capacitance retention rate reached 89%. This result can be attributed to annealing, which can further remove unfavourable surface groups, such as –F or –Cl, and then improve conductivity capacitance and rate performance. This study can provide an effective approach to the preparation of high-performance supercapacitor electrode materials.

Shrimp aquaculture environments are a natural reservoir of multiple antibiotic resistance genes (ARGs) due to the overuse of antibiotics. Nowadays, the prevalence of these kinds of emerging contaminants in shrimp aquaculture environments is still unclear. In this study, high-throughput sequencing techniques were used to analyze the distribution of ARGs and mobile genetic elements (MGEs), bacterial communities, and their correlations in water and sediment samples in two types of typical shrimp (Procambarus clarkii and Macrobrachium rosenbergii) freshwater aquaculture environments. A total of 318 ARG subtypes within 19 ARG types were detected in all the samples. The biodiversity and relative abundance of ARGs in sediment samples showed much higher levels compared to water samples from all ponds in the study area. Bacitracin (17.44–82.82%) and multidrug (8.57–49.70%) were dominant ARG types in P. clarkii ponds, while sulfonamide (26.33–39.59%) and bacitracin (12.75–37.11%) were dominant ARG types in M. rosenbergii ponds. Network analysis underlined the complex co-occurrence patterns between bacterial communities and ARGs. Proteobacteria, Cyanobacteria, and Actinobacteria exhibited a high abundance in all samples, in which C39 (OTU25355) and Hydrogenophaga (OTU162961) played important roles in the dissemination of and variation in ARGs based on their strong connections between ARGs and bacterial communities. Furthermore, pathogens (e.g., Aeromonadaceae (OTU195200) and Microbacteriaceae (OTU16033)), which were potential hosts for various ARGs, may accelerate the propagation of ARGs and be harmful to human health via horizontal gene transfer mediated by MGEs. Variation partitioning analysis further confirmed that MGEs were the most crucial contributor (74.76%) driving the resistome alteration. This study may help us to understand the non-ignorable correlations among ARGs, bacterial diversity, and MGEs in the shrimp freshwater aquaculture environments.

Tungsten-copper (W–Cu) composites are widely used as electrical contact materials, resistance welding, electrical discharge machining (EDM), and plasma electrode materials due to their excellent arc erosion resistance, fusion welding resistance, high strength, and superior hardness. However, the traditional preparation methods pay little attention to the compactness and microstructural uniformity of W–Cu composites. Herein, W–Cu composite coatings are prepared by pulse electroplating using nano-W powder as raw material and the influence of forward-reverse duty cycle of pulse current on the structure and mechanical properties is systematically investigated. Moreover, the densification mechanism of the W–Cu composite coating is analyzed from the viewpoints of forward-pulse plating and reverse-pulse plating. At the current density (J) of 2 A/dm2, frequency (f) of 1500 Hz, forward duty cycle (df) of 40% and reverse duty cycle (dr) of 10%, the W–Cu composite coating rendered a uniform microstructure and compact structure, resulting in a hardness of 127 HV and electrical conductivity of 53.7 MS/m.

In the present study, high-purity ternary-phase nitride (Ti2AlN) powders were synthesized through microwave sintering using TiH2, Al, and TiN powders as raw materials. X-ray diffraction (XRD), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were adopted to characterize the as-prepared powders. It was found that the Ti2AlN powder prepared by the microwave sintering of the 1TiH2/1.15Al/1TiN mixture at 1250 °C for 30 min manifested great purity (96.68%) with uniform grain size distribution. The formation mechanism of Ti2AlN occurred in four stages. The solid-phase reaction of Ti/Al and Ti/TiN took place below the melting point of aluminum and formed Ti2Al and TiN0.5 phases, which were the main intermediates in Ti2AlN formation. Therefore, the present work puts forward a favorable method for the preparation of high-purity Ti2AlN powders.

In this work, accumulative pack-roll bonding successfully manufactured the Ni/Ti/Nb multilayer composite. The microstructure evolution and mechanical properties of the composite during the accumulative roll bonding (ARB) process were investigated by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), micro-hardness test, and tensile tests. The results showed that the deformation of each layer was relatively uniform in the initial stage of the ARB process. After the fourth pass, the Ni/Ti interface was still relatively straight, while the Ti/Nb interface was unevenly deformed. After the fourth pass, the microstructure of the Ni layer was equiaxed grains with a decreased grain size of 200 nm, and finer equiaxed grains were observed at the interface. No dynamic recrystallization occurred in the Ti and Nb layers. The laminar structure of the Nb layer was observed, and the grains were oriented parallel to the rolling direction. Moreover, the tensile strength and micro-hardness significantly increased as the number of ARB increased. After five passes of the ARB process, the tensile strength of the composite reached 792.3 MPa, and the micro-hardness of Ni, Ti, and Nb were increased to 270.2, 307.4, and 243.4 HV, respectively.

In recent years, power grid accidents have occurred frequently and higher requirements have been placed on their safety operation. In current safety management in the world, there is an effective practice that uses a unified standard for structuring an accident case database and based on that database, conducts quantitative analysis to cope with accident risks. However, that is not the case for power safety management. Case-based reasoning (CBR) is such a process that solves new problems based on the solutions to similar past problems. It works by matching a current problem with historical cases and solutions in a database, in order to obtain similar case solutions or inspirations. In the matching process, if necessary, such past solutions may be modified in order to better adapt to the current actual problems. Based on the CBR method, this paper proposes how to construct a case database of power grid operational accidents, provide data support for management of power grid risks and provide knowledge services for accurate grasping of grid accident development dynamics and making quick decisions to rapidly response to the emergencies. First, it designs an operational accident case database after considering the following three aspects: case features, power grid features and accident features based on safety management theory. Secondly, in terms of how to use the power grid operational accident case database, it proposed a two-level search strategy, as well as the corresponding similarity calculation methods for different feature attributes of the case. Finally, it carried out a demonstration to verify the model by selecting four typical grid accidents. The grid database and CBR strategy proposed in this article could help China’s power grids practice intelligent analysis of grid operational accidents and improve digitalization in safety management.

Joint biomarker responses, oxidative stress and membrane systems, were determined for nano-metal-oxides (nMeO, i.e., nCeO2, nMgO, and nFe3O4) and sulfadiazine (SDZ) exposed at relevant low concentrations to two freshwater microalgae Scenedesmus obliquus and Chlorella pyrenoidosa. The impacts of dissolved organic matter (DOM) on the joint biomarker responses were also investigated. Results indicated that the presence of SDZ significantly decreased the level of intercellular reactive oxygen species (ROS) in the algal cells exposed to each nMeO. Reduction of cell membrane permeability (CMP) and mitochondrial membrane potential (MMP) in the algal cells was observed when the algae were exposed to the mixture of SDZ and the nMeO. The degree of reduction of the ROS level, CMP, and MMP significantly went down with the addition of DOM to a certain extent. Changes in cellular oxidative stress and membrane function depended on the types of both nMeO and algal species. This contribution provides an insight into the hazard assessment of a mixture consisting of emerging contaminants and DOM, as they can coexist in the aquatic environment.

Diacylglycerol kinase (DGK) is an enzyme that plays a pivotal role in abiotic and biotic stress responses in plants by transforming the diacylglycerol into phosphatidic acid. However, there is no report on the characterization of soybean DGK genes in spite of the availability of the soybean genome sequence. In this study, we performed genome-wide analysis and expression profiling of the DGK gene family in the soybean genome. We identified 12 DGK genes (namely GmDGK1-12) which all contained conserved catalytic domains with protein lengths and molecular weights ranging from 436 to 727 amino acids (aa) and 48.62 to 80.93 kDa, respectively. Phylogenetic analyses grouped GmDGK genes into three clusters—cluster I, cluster II, and cluster III—which had three, four, and five genes, respectively. The qRT-PCR analysis revealed significant GmDGK gene expression levels in both leaves and roots coping with polyethylene glycol (PEG), salt, alkali, and salt/alkali treatments. This work provides the first characterization of the DGK gene family in soybean and suggests their importance in soybean response to abiotic stress. These results can serve as a guide for future studies on the understanding and functional characterization of this gene family.

Metal-based nanoparticles (NPs) are the most widely used engineered nanomaterials. The individual toxicities of metal-based NPs have been plentifully studied. However, the mixture toxicity of multiple NP systems (n ≥ 3) remains much less understood. Herein, the toxicity of titanium dioxide (TiO2) nanoparticles (NPs), silicon dioxide (SiO2) NPs and zirconium dioxide (ZrO2) NPs to unicellular freshwater algae Scenedesmus obliquus was investigated individually and in binary and ternary combination. Results show that the ternary combination systems of TiO2, SiO2 and ZrO2 NPs at a mixture concentration of 1 mg/L significantly enhanced mitochondrial membrane potential and intracellular reactive oxygen species level in the algae. Moreover, the ternary NP systems remarkably increased the activity of the antioxidant defense enzymes superoxide dismutase and catalase, together with an increase in lipid peroxidation products and small molecule metabolites. Furthermore, the observation of superficial structures of S. obliquus revealed obvious oxidative damage induced by the ternary mixtures. Taken together, the ternary NP systems exerted more severe oxidative stress in the algae than the individual and the binary NP systems. Thus, our findings highlight the importance of the assessment of the synergistic toxicity of multi-nanomaterial systems.

Background: Eustachian tube dysfunction (ETD) is a common disorder causing ear pressure, pain, and hearing loss. Balloon Eustachian tuboplasty (BET) is an emerging technique for dilating the Eustachian tube and treating ETD. Whether adding myringotomy improves BET efficacy is controversial. Methods: This retrospective study included 95 ETD patients undergoing BET alone (n = 44) or BET with myringotomy (BET + M; n = 51) between June 2020 and August 2021 at a single medical center. The primary outcome was the change in ETDQ-7 symptom scores from baseline to 6 months after treatment. Secondary outcomes included audiometry, endoscopy, Valsalva maneuver, and complications. Results: The ETDQ-7 scores improved significantly after treatment in both groups (p < 0.001), without significant between-group differences (p = 0.417). No significant differences occurred in the audiometry, endoscopy, and Valsalva results or in most complications between groups. One BET + M patient had a persistent tympanic membrane perforation. Conclusions: Both BET alone and BET + M effectively and safely improved the subjective and objective ETD outcomes. However, adding myringotomy did not further improve the outcomes over BET alone, while it incurred risks such as persistent perforation. BET alone may sufficiently treat ETD without requiring myringotomy in this cohort. Further randomized controlled trials should identify optimal candidates for BET alone versus combined approaches.

Deregulation of the Wnt signaling pathway leads to colorectal cancer progression. Natural dietary compounds serve as promising candidates for development as chemopreventive agents by suppressing the Wnt/β-catenin signaling pathway. Physalis peruviana-derived 4βHWE showed a significant inhibitory activity with a calculated IC50 of 0.09 μΜ in a screening of novel inhibitors of Wnt signaling with the dual-luciferase reporter assay. This study investigated the anti-tumor effect of 4βHWE and the potential Wnt signaling inhibitory mechanism. Both the western blot analysis and immunofluorescence assay showed that 4βHWE promoted the phosphorylation and degradation of β-catenin and the subsequent inhibition of its nuclear translocation to attenuate the endogenous Wnt target gene expression in colorectal cancer (CRC) cells. The cell viability assay indicated that 4βHWE preferentially inhibited the proliferation of CRC compared with CCD-841-CoN, a normal human colonic epithelial cell line. 4βHWE-mediated G0/G1 cell cycle arrest and apoptosis induction contributed to the suppression of the proliferation of CRC in the cell cycle and Annexin V-FITC/Propidium Iodide apoptosis analysis. Moreover, in vivo, 4βHWE dramatically inhibited tumor growth in HCT116 xenografts by attenuating the Wnt/β-catenin signaling pathway. In conclusion, our study suggested that 4βHWE could be of potential use in anti-tumor agent development as a novel Wnt signaling inhibitor.

Toll-like receptor 4 (TLR4) has been proven to play a critical role in neuroinflammation and to represent an important therapeutic target following subarachnoid hemorrhage (SAH). Resveratrol (RSV), a natural occurring polyphenolic compound, has a powerful anti-inflammatory property. However, the underlying molecular mechanisms of RSV in protecting against early brain injury (EBI) after SAH remain obscure. The purpose of this study was to investigate the effects of RSV on the TLR4-related inflammatory signaling pathway and EBI in rats after SAH. A prechiasmatic cistern SAH model was used in our experiment. The expressions of TLR4, high-mobility group box 1 (HMGB1), myeloid differentiation factor 88 (MyD88), and nuclear factor-κB (NF-κB) were evaluated by Western blot and immunohistochemistry. The expressions of Iba-1 and pro-inflammatory cytokines in brain cortex were determined by Western blot, immunofluorescence staining, or enzyme-linked immunosorbent assay. Neural apoptosis, brain edema, and neurological function were further evaluated to investigate the development of EBI. We found that post-SAH treatment with RSV could markedly inhibit the expressions of TLR4, HMGB1, MyD88, and NF-κB. Meanwhile, RSV significantly reduced microglia activation, as well as inflammatory cytokines leading to the amelioration of neural apoptosis, brain edema, and neurological behavior impairment at 24 h after SAH. However, RSV treatment failed to alleviate brain edema and neurological deficits at 72 h after SAH. These results indicated that RSV treatment could alleviate EBI after SAH, at least in part, via inhibition of TLR4-mediated inflammatory signaling pathway.