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Global climate change, particularly rising CO2 concentration, has significantly impacted insect growth, development, and reproduction. Agasicles hygrophila (Coleoptera: Chrysomelidae) is a specialist natural enemy of the invasive weed Alternanthera philoxeroides (Amaranthaceae: Alternanthera). Methoprene-tolerant (Met), the Juvenile hormone (JH) receptor, regulates development, metamorphosis, and reproduction in insects. While Met gene has been characterized in several insect species, its role in A. hygrophila remains unclear. This study investigated the function of Met gene (AhMet) and its effects on A. hygrophila reproduction under elevated CO2. The AhMet transcript was first cloned and sequenced, and sequence analysis revealed that the AhMet gene contained conserved bHLH, PAS-A, and PAS-B domains. AhMet expression was highest in adults and significantly upregulated in the elevated CO2 treatment (eCO2) on day 1 after female emergence. RNA interference (RNAi) of dsMet reduced AhMet expression in both the ambient CO2 treatment (a-dsMet) and the elevated CO2 treatment (e-dsMet) groups within 25 days. Interestingly, after 12 days of silencing, AhMet expression in the e-dsMet treatment remained higher than in the a-dsMet treatment. In addition, RNAi-mediated AhMet knockdown inhibited ovary development, oviposition, and reduced survival. However, the e-dsMet treatment displayed significantly higher ovary development, survival rates, and oviposition compared to e-dsGFP and a-dsMet treatments. These results demonstrate that AhMet is essential for ovary development and reproduction in A. hygrophila, and support its role in promoting reproduction under elevated CO2. [ABSTRACT FROM AUTHOR]

The distribution network line loss rate is a crucial factor in improving the economic efficiency of power grids. However, the traditional prediction model has low accuracy. This study proposes a predictive method based on data preprocessing and model integration to improve accuracy. Data preprocessing employs dynamic cleaning technology with machine learning to enhance data quality. Model integration combines long short-term memory (LSTM), linear regression, and extreme gradient boosting (XGBoost) models to achieve multi-angle modeling. This study employs regression evaluation metrics to assess the difference between predicted and actual results for model evaluation. Experimental results show that this method leads to improvements over other models. For example, compared to LSTM, root mean square error (RMSE) was reduced by 44.0% and mean absolute error (MAE) by 23.8%. The method provides technical solutions for building accurate line loss monitoring systems and enhances power grid operations. [ABSTRACT FROM AUTHOR]

The effect of nine constant temperatures on developmental time of Oligota flavicornis (Boisduval and Lacordaire) preying on Tetranychus cinnabarinus (Boisduval) (Acari: Tetranychidae) eggs was determined under laboratory conditions of 75 ± 5% RH and a 16:8 (L:D) h photoperiod. O. flavicornis survival rates were highest between 18 and 30°C, although O. flavicornis eggs developed successfully to adults at 12–32°C, and the developmental durations to adult at the seven temperatures (12, 15, 18, 20, 25, 30, and 32°C) were 114.41, 51.66, 33.45, 23.21, 13.43, 11.54, and 17.18 d, respectively. Two linear and seven nonlinear models (Logan-6 and Logan-10, Taylor, Lactin-1 and Lactin-2, and Brière-1 and Brière-2) were fit to the developmental rates of the immature predatory stages to estimate the thermal constant (K) and critical temperatures. The lower temperature threshold (T0) and K for the immature stages using the common linear model were 9.96°C and 225.73 degree-days and Ikemoto–Takai linear model were 11.01°C and 167.14 degree-days, respectively. The upper temperature threshold values estimated by the Logan-6 and Lactin-1 models were both 34.86°C. The T0 values estimated by the Brière-1 and Brière-2 models were 10.67 and 9.32°C for all immature stages, respectively, and the estimated optimal temperature according to the Brière-2 model was 29.59°C. Therefore, the two linear models and Brière-2 model estimates approximated the actual relationship between the temperature and developmental rate of immature O. flavicornis. [ABSTRACT FROM AUTHOR]

The presence of microystins (MCs) in water has the potential to harm people's health. In the MCs various isomers, MC-LR has the strongest toxicity and is the most harmful one. At present, several kinds of pre-oxidants, which are commonly used in water treatment process, are effective to remove MC-LR. However, it is still not clear about their degeneration mechanisms. Chlorine and potassium permanganate were selected in the present work since they are used worldwide for preoxidation treatment. Using the testing method of HPLC-MS, studies on the degeneration of MC-LR were conducted. The results indicate that HPLC-MS is creditable and sensitive. It was also found that linear relationship between concentration of MC-LR and peak area holds in the range of 5-500 μg·L-1 on the calibration curves, the correlation coefficient (R 2) is 0.9993. Under the general condition of oxidant dose and reaction time, MC-LR was degraded rapidly. With active chlorine and potassium permanganate the degradation reaction followed the mode of first-order kinetics. The molecular weight of the degradation product was determined through analyzing the full-scan mass spectrum of MC-LR. And the oxidative degradation mechanism of MC-LR was discussed as well. [ABSTRACT FROM AUTHOR]

Regular MgO nanoflowers were synthesized via a simple chemical route. The as-synthesized nanoflowers are single crystalline and consist of MgO nanofibers which have lengths up to several micrometers and diameters in the range of 20–80 nm, with an average of 50 nm. The frequency spectra of the relative dielectric constant and the dielectric loss were measured in the frequency range of 50 Hz to 5 MHz. Temperature spectra of the relative dielectric constant were also measured and the experimental results showed that MgO nanoflowers have a much higher relative dielectric constant as compared with MgO micropowders, especially at low frequencies at room temperature. [ABSTRACT FROM AUTHOR]

Ordered Ni/Au multilayer nanowire arrays are successfully fabricated inside the nanochannels of anodic aluminum oxide template by pulse electrodeposition method. The thickness of the alternating layers is controlled to examine the magnetostatic interaction in Ni/Au multilayer nanowires. The magnetic easy axis parallel to the nanowires indicates that here the magnetostatic coupling along the wire axis dominates over the interactions perpendicular to the nanowires. However, the magnetostatic interaction between adjacent nanowires with larger magnetic layers is enhanced, leading to the existence of an optimum coercivity value. [ABSTRACT FROM AUTHOR]

A novel hollow urchin-like hierarchical structure of ZnO nanorods grown on hollow MgO microspheres has been prepared through a simple one-step chemical vapor deposition method. Photoluminescence property and possible growth mechanism of the ZnO/MgO hierarchical structures have also been discussed. [ABSTRACT FROM AUTHOR]

Using a simple assistant thermal decomposition method, metal cadmium nanowires were large-scale fabricated from CdS powders in an argon atmosphere. Investigation results demonstrate that the Cd nanowires have lengths of several microns and diameter of about 70-150 nm. [ABSTRACT FROM AUTHOR]

The hollow porous MgO microspheres have been synthesized through a simple in situ chemical vapor deposition method, and the investigations reveal that Zn in raw source is key and possibly acts as an interim template in the formation of MgO hollow-sphere morphology. [ABSTRACT FROM AUTHOR]