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Abamectin resistance was selected in the vegetable leafminer, Liriomyza sativae (Blanchard) (Diptera: Agromyzidae) under laboratory conditions, and cross-resistance patterns and possible resistance mechanisms in the abamectin-resistant strains (AL-R, AF-R) were investigated. Compared with the susceptible strain (SS), strain AL-R displayed 39-fold resistance to abamectin after 20 selection cycles during 25 generations, and strain AF-R exhibited 59-fold resistance to abamectin after 16 selection cycles during 22 generations. No cross-resistance to cyromazine was found in both abamectin-resistant strains. However, we failed to select for cyromazine resistance in L. sativae under laboratory conditions by conducting 17 selection cycles during 22 generations. However, moderate levels of cross-resistance to abamectin (6-9 fold) were observed in strains which received cyromazine treatments. Biochemical analysis showed that glutathione S-transferase (GST) activity in both abamectin-resistant strains (AL-R, AF-R) was significantly higher than in the susceptible strain (SS), suggesting metabolically driven resistance to abamectinin L. sativae. Recommendations of mixtures or rotation of cyromazine and abamectin should be considered carefully, as consecutive cyromazine treatments may select for low-level cross-resistance to abamectin. [ABSTRACT FROM AUTHOR]

The time-resolved photoluminescence spectra of ordered and disordered Ga0.52In0.48P alloys were studied at room temperature and at 77 K liquid nitrogen, respectively. The ordered samples have well fitted two exponential processes decay curves and the time constants are sample dependent and have little relationship with the ordering degree. The decay curve of disordered sample shows that it has single exponential process and its lifetime has a tendency of reduction with the decrease of excitation intensity. The photoluminescence spectra with different delay time at 77 K show that the ordered samples exhibit about 6 ∼ 10 meV blue-shift of PL peak energy with the delay time. [ABSTRACT FROM AUTHOR]

Professor Li was strong-willed and always worked hard.3 Although we are not able to see him anymore, his legacy, not only his scientific contributions but his great integrity, his noble character and his life of service to agrochemistry, will live on in each of us - his family, his friends, his colleagues and his students. GRAPH Professor Zheng-Ming Li, a remarkable educator and chemist, passed away at the age of 90 on October 4th, 2021 in Tianjin, China. He pioneered pesticide chemistry research for world food security and science, making outstanding contributions.2 In the early 1990s, Professor Li, leading his team, carried out systematic basic research on sulfonylurea herbicides. [Extracted from the article]

Background: The potato tuber moth (PTM), Phthorimaea operculella, is an economically important pest of potato crops worldwide. So far, the application of chemical pesticides is the major measure to manage PTM, but it induces serious deleterious impacts on the environment and human health. Here, we screened the entomopathogenic fungi that are lethal to PTM, and tested their sublethal impacts on PTM development, mortality, and reproduction as well as that of ectoparasitic mite Pyemotes zhonghuajia, a natural enemy of PTM., Results: Among 13 tested entomopathogenic fungal strains in three genera, Beauveria Vuillemin, Cordyceps Fries, and Talaromyces Benjamin, Cordyceps fumosorosea (strain KY1136) and Beauveria bassiana (strain KY1115) caused a significantly higher mortality in PTM eggs, larvae, and pupae. Median lethal concentration (LC 50 ) of both strains prolonged PTM immature development, shortened adult longevity, and reduced fecundity and life table parameters in terms of intrinsic rate of increase (r m ), net reproductive rate (R 0 ), and finite rate of increase (λ). The LC 50 value of KY1136 (1.9 × 10 6 spores/mL) was lower than that of KY1115 (9.0 × 10 6 spores/mL), indicating the greater potential for biological control of PTM by KY1136. Both strains had no significant impact on P. zhonghuajia survival and reproduction. Increasing P. zhonghuajia density reduced PTM feeding and pupation rate, while the combined application of P. zhonghuajia and entomopathogenic fungi had no additional effect in inhabiting PTM feeding and pupation., Conclusion: Entomopathogenic fungal strains Cordyceps fumosorosea KY1136 and Beauveria bassiana KY1115 are the potential biological control agents of PTM, but do not impose a negative impact on the natural enemy. Our study provides insights into the integrated pest management of PTM by combining the entomopathogenic fungi and an ectoparasitic mite. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Background: The treatment of postoperative anastomotic stenosis after excision of rectal cancer is challenging. Endoscopic balloon dilation and radial incision are not effective in all patients. We present a new endoscopy-assisted magnetic compression technique (MCT) for the treatment of rectal anastomotic stenosis. We successfully applied this MCT to a patient who developed an anastomotic stricture after radical resection of rectal cancer., Case Summary: A 50-year-old man had undergone laparoscopic radical rectal cancer surgery at a local hospital 5 months ago. A colonoscopy performed 2 months ago indicated that the rectal anastomosis was narrow due to which ileostomy closure could not be performed. The patient came to the Magnetic Surgery Clinic of the First Affiliated Hospital of Xi'an Jiaotong University after learning that we had successfully treated patients with colorectal stenosis using MCT. We performed endoscopy-assisted magnetic compression surgery for rectal stenosis. The magnets were removed 16 d later. A follow-up colonoscopy performed after 4 months showed good anastomotic patency, following which, ileostomy closure surgery was performed., Conclusion: MCT is a simple, non-invasive technique for the treatment of anastomotic stricture after radical resection of rectal cancer. The technique can be widely used in clinical settings., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

The degradation of AlGaN-based UVC LEDs under constant temperature and constant current stress for up to 500 hrs was analyzed in this work. During each degradation stage, the two-dimensional (2D) thermal distributions, I-V curves, optical powers, combining with focused ion beam and scanning electron microscope (FIB/SEM), were thoroughly tested and analyzed the properties and failure mechanisms of UVC LEDs. The results show that: 1) the opto-electrical characteristics measured before/during stress indicate that the increased leakage current and the generation of stress-induced defects increase the non-radiative recombination in the early stress stage, resulting in a decrease in optical power; 2) the increase of temperature caused by the deterioration of the Cr/Al layer of p-metal after 48 hrs of stress aggravates the optical power in UVC LEDs. The 2D thermal distribution in conjunction with FIB/SEM provide a fast and visual way to precisely locate and analyze the failure mechanisms of UVC LEDs.