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An unusual diastereodivergent stereoselective allylation reaction is presented. It consists of a palladium-catalyzed allylation reaction of an organocatalytically generated amino isobenzofulvene, where the diastereoselectivity is controlled by the electronic properties of a monodentate, achiral ligand on palladium. One major diastereoisomer is formed using triarylphosphines substituted with neutral or electron-donating substituents of the aryl group, while those with electron-withdrawing substituents favor the other diastereoisomer. The diastereoselectivity correlates with the Taft inductive parameter of substituents on the triarylphosphine ligand on palladium. The synergistic reaction involves both a catalytic secondary amine catalyst for the indene-aldehyde activation and the monodentate phosphine ligands on palladium, affording a highly enantioselective reaction with up to 98 % enantiomeric excess. Based on computational investigations, the role of the monodentate phosphine ligand on the diastereoselectivity is discussed.

Objective: Bedtime procrastination is a type of unhealthy sleep behavior, but whether it affects sleep quality remains unknown. The current study aimed to examine the relationship between bedtime procrastination and poor sleep quality among Chinese college students. Participants: A total of 1550 Chinese undergraduates participated and effectively completed the study. Methods: This cross-sectional study collected information on bedtime procrastination and self-reported sleep quality via the Bedtime Procrastination Scale and the Pittsburgh Sleep Quality Index. Results: The prevalence of poor sleep quality was 39.42% among Chinese undergraduates. Age, education, and bedtime procrastination independently predicted the prevalence of poor sleep quality. Bedtime procrastination was a unique contributor to the severity of poor sleep quality. Conclusions: This study highlighted the independent associations between bedtime procrastination and the prevalence and severity of self-reported poor sleep quality. These findings may be helpful in designing effective measures to improve the sleep quality of college students.

With the large-scale integration of distributed new energy sources into power grids and the wide application of power electronics， the power grid’s risk of oscillation has reached epidemic proportions and is resolving into broadband domain oscillation. Given the lack of effective means to monitor the broadband domain characteristics of the power grid on the dispatching side， a grid-oriented broadband monitoring system is developed. First， the hardware and software architectures of the system are introduced， and a broadband monitoring model is designed based on two mainstream extended versions of harmonic communication specifications. Then， a unified broadband data acquisition architecture and a unified broadband data service technology are proposed. Functional modules such as harmonic/interharmonic overrun alarm， historic broadband data query， and broadband oscillation alarm forwarding are developed to realize distributed acquisition， centralized monitoring， and analysis of high-capacity and high-rate broadband signals. Finally， it is shown through engineering practice that the broadband monitoring system provides powerful data support for dynamic monitoring， risk identification， prevention， and control in the more broadband domains in power grids.

ObjectiveTo investigate the resistance to pyrethroids， beta-cyhalothrin and fenitrothion as well as the frequencies of kdr and ace⁃1 alleles in Anopheles sinensis from three geographical populations in Chongming District， Shanghai.MethodsThe contact tube method recommended by WHO was used to determine mosquito resistance. The frequencies of kdr and ace⁃1 alleles in adult mosquitoes were determined by PCR amplification. The correlation between the frequencies of kdr alleles and insecticide resistance was analyzed by linear regression method.ResultsThe mosquito population near natural reserve （NF） was sensitive to deltamethrin， and the mortality rate was 100.00% at 24 h. The mosquito population with intensive breeding farms （HX） showed resistance to deltamethrin and beta-cyhalothrin， and the 24 h mortality was 48.00 % and 57.50 %， respectively. The 24 h mortality rate of the mosquito population with urban-rural integration area （AS） with suspected resistance to deltamethrin and beta-cyhalothrin was 84.40% and 86.00%. The 24 h mortality rate to Fenitrothion was 55.67%. There were 3 mutations in kdr gene locus 1014， and 7 mutated genotypes were detected， mainly L1014/L1014F and L1014F/L1014F. The mutation frequency of kdr allele in HX population was the highest （52.68%）. There was one mutation at site 119 of ace⁃1 gene， and three genotypes were detected， most of which were G119S mutation. There was a significant negative correlation between the frequency of kdr resistance allele and the mortality rate of beta-cypermethrin in An.sinensis populations （r2=0.930，P=0.036）. There was a significant negative correlation between the frequency of ace⁃1 resistance allele and the mortality rate of fenitrothion in An. sinensis populations from four habitats （r2=0.996，P=0.038）.ConclusionThe mutation frequency of insecticide resistance allele is associated with the development of mosquito resistance level. Therefore， comprehensive monitoring of resistance levels of An.sinensis in Chongming area should be continued to provide a basis for local mosquito resistance management.

The ability to reversibly and non-invasively modulate region-specific brain activity in vivo suggests Low Intensity Focused Ultrasound (LIFU) as potential therapeutics for neurological dysfunctions such as epilepsy and Parkinson's disease. While in vivo studies provide evidence of the bioeffects of LIFU on neuronal activity, they merely hint at potential mechanisms but do not fully explain how this technology achieves these effects. One potential hypothesis is that LIFU produces local membrane depolarization by mechanically perturbing the neuronal cell membrane, or activating channels or other proteins embedded in the membrane. Proteins that sense mechanical perturbations of the membrane, such as those gated by membrane tension, are prime candidates for activating in response to LIFU and thus leading to the neurological responses that have been measured. Here we use the bacterial mechanosensitive channel MscL, which has been purified and reconstituted in liposomes, to determine how LIFU may affect the activation of this membrane-tension gated channel. Two bacterial voltage-gated channels, KvAP and NaK2K F92A channels were also studied. Surprisingly, the results suggest that ultrasound modulation and membrane perturbation does not induce channel gating, but rather induces pore formation at the membrane protein-lipid interface. However, in vesicles with high MscL mechanosensitive channel concentrations, apparent decreases in pore formation are observed, suggesting that this membrane-tension-sensitive protein may serve to increase the elasticity of the membrane, presumably because of expansion of the channel in the plane of the membrane independent of channel gating.