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We consider the following nonlinear nonlocal elliptic problem: −a+b∫R3∣∇ψ∣2dxΔψ+λψ=∫R3G(ψ(y))∣x−y∣αdyG′(ψ),x∈R3,-\left(a+b\mathop{\int }\limits_{{{\mathbb{R}}}^{3}}{| \nabla \psi | }^{2}{\rm{d}}x\right)\Delta \psi +\lambda \psi =\left(\mathop{\int }\limits_{{{\mathbb{R}}}^{3}}\frac{G\left(\psi (y))}{{| x-y| }^{\alpha }}{\rm{d}}y\right)G^{\prime} \left(\psi ),\hspace{1em}x\in {{\mathbb{R}}}^{3}, where a,b>0a,b\gt 0 are constants, λ>0\lambda \gt 0 is a parameter, α∈(0,3)\alpha \in \left(0,3), and G∈C1(R,R)G\in {{\mathcal{C}}}^{1}\left({\mathbb{R}},{\mathbb{R}}). By using variational methods, we establish the existence of least energy solutions for the above equation under conditions on the nonlinearity GG we believe to be almost necessary. Some qualitative properties of the least energy solutions are also obtained

Objective To explore the risk factors of mortality for children with Streptococcus pneumococcal meningitis. Methods A retrospective analysis was conducted on the clinical data of 41 hospitalized children diagnosed as Streptococcus pneumoniae menigitis in Jiangxi Children‘s Hospital from January 2016 to December 2018. According to the prognosis of disease, the patients were divided into the death group (n=10) and the survival group (n=31). The clinical characteristics, laboratory indicators and treatment effect were compared between two groups, and the risk factors of mortality were analyzed by multivariate logistic regression analysis. Results The case fatality rate of Streptococcus pneumoniae menigitis was 24.4%. The proportions of convulsions, platelet count500 U/L) and cerebrospinal fluid (>3 g/L) and undergoing mechanical ventilation were the influencing factors of the death for children with Streptococcus pneumoniae menigitis. Multivariate analysis showed that high level of lactate dehydrogenase (>500 U/L, OR=27.874, 95%CI：1.253-619.966) and mechanical ventilation (OR=30.591, 95%CI：1.097-853.089) were the risk factors for the death in children with PM (P

Insecticide resistance in Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) is a major constraint on the global production of cruciferous crops. For effective management of insecticide resistance, it is necessary to develop a molecular detection tool for predicting insecticide resistance levels based on the mutation frequency of target sites. In this study, a susceptible strain (SHggt) of P. xylostella was subjected to chlorantraniliprole and tetraniliprole selection under laboratory conditions to obtain the CHLSel and TETSel strains, respectively, to determine their resistance development, cross-resistance and mutation frequencies of the P. xylostella ryanodine receptor (Px RyR). In addition, the tetraniliprole resistance and the mutation frequencies of the Px RyR from 7 field populations were evaluated. Continuous selection over 30 generations resulted in resistance ratios (RRs) of 7,073.2-fold and 6,971.0-fold for the CHLSel and TETSel strains, respectively, and thousandfold increases in cross-resistance to unexposed diamides, e.g. cyantraniliprole and flubendiamide, were observed. For the field populations, three out of seven populations have developed more than thousandfold resistance to tetraniliprole. Among the three investigated target site mutations in Px RyR, only I4790K was detected in both laboratory-selected strains. However, 2 mutations, I4790K and G4946E, were detected in field populations. A positive correlation between RRs and K allele frequencies was observed in the laboratory-selected/relaxed strains and field populations of P. xylostella. These results suggest a possible link between the development of anthranilic diamide resistance and the frequency of the Px RyR I4790K mutation, which can be used to develop effective strategies for diamide resistance management in P. xylostella. [ABSTRACT FROM AUTHOR]

BACKGROUND: Aedes aegypti is a widespread mosquito in tropical and subtropical regions that causes significant mortality and morbidity in humans by transmitting diseases, such as dengue fever and Zika virus disease. Synthetic insecticides, such as pyrethroids, have been used to control Ae. aegypti, but these insecticides can also affect nontarget organisms and contaminate soil and water. This study aimed to investigate the mosquitocidal activity of Pseudomonas mosselii isolated from pond sludge against larvae of Ae. aegypti. RESULTS: Based on the initial results, similar time‐course profiles were obtained for the mosquitocidal activity of the bacterial culture and its supernatant, and the pellet resuspended in Luria–Bertani (LB) medium also showed delayed toxicity. These results imply that the toxic component can be released into the medium from live bacteria. Further research indicated that the toxic component appeared in the supernatant approximately 4 h after a 3‐mL stock was cultured in 200 mL of LB medium. The stabilities of the P. mosselii culture and supernatant stored at different temperatures were also evaluated, and the best culture stability was obtained at 28 °C and supernatant stability at 4 °C. The bacterial culture and supernatant were toxic to larvae and pupae of not only susceptible Ae. aegypti but also pyrethroid‐resistant strains. CONCLUSION: This study highlights the value of the mosquitocidal activity of P. mosselii, which has potential as an alternative insecticide to control pyrethroid‐resistant Ae. aegypti in the field. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The online detection of liquid flow rate in gas-liquid two-phase flow has become an important factor in ensuring the safe operation of gas wells. In this paper, the real-time measurement of liquid holdup in gas-liquid two-phase flow is carried out by analyzing the characteristics of vibration signals excited by gas-liquid two-phase flow impacting on the pipe wall. Firstly, an acceleration sensing detection and processing system is constructed to obtain the vibration signals excited by gas-liquid two-phase flow impacting on the pipe wall. Then, the pure airflow vibration signals at different flow velocities and the gas-liquid two-phase flow excitation vibration signals at different liquid flow rates are tested, respectively, and the time-frequency characteristics analysis based on STFT is implemented. The practice shows the following: firstly, the frequency band of 6.5−15 Hz is identified as the characteristic frequency band of liquid flow rate in gas-liquid two-phase flow. Secondly, the liquid holdup is positively correlated with the vibration energy in its characteristic frequency band. Thirdly, a mathematical model of the relationship between liquid flow rate and vibration energy is constructed. Finally, the measurement error of liquid holdup is within 10%. This research method has laid a good foundation for the subsequent detection of characteristic parameters of each phase in gas-solid-liquid complex multiphase flow fluids, and it has certain application and promotion value.

A built-in wave energy converter (BI-WEC) is a type of WEC that is fully encapsulated within a floating body that is easy to integrate and promotes reliability. Significant advantages in integration and reliability make BI-WECs a promising pathway to achieve an in situ power supply for massive distributed marine equipment (such as ships, buoys, or USVs). A comprehensive review of the recent advances in built-in wave energy converters can help address the most relevant issues in BI-WEC development. This study enumerates recent progress on BI-WECs (energy capture, power take-off, and control) and summarizes the characteristics of various designs. Different design philosophies and technical pathways can be better understood through the classification and analysis offered by this study. This review helps to form a basic understanding of BI-WEC development to achieve in situ power sustainability for a large amount of distributed marine equipment in long-term sustained marine operations. [ABSTRACT FROM AUTHOR]