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We present a numerical study of the plasmonic properties of Au core-semishell. Symmetry breaking in semishell results in a dipole–quadrupole Fano resonance without the offset of the Au core. The plasmon hybridization theory is applied to interpret the origin of the localized hybrid plasmon modes and Fano resonances. The multiple hybrid plasmon modes resonance can be excited for the extreme core offset inducing high order dark modes visible. The Fano resonances can be tuned by changing the size of the Au core, the degree of symmetry breaking of the semishell, and the dielectric properties of local environment. The tunability of the plasmon resonances and Fano resonances in Au core-semishell provides potential application for tunable nanophotonic devices, such as filters and sensors.

Recent studies have shown that some serine protease family members may play an important role in antibacterial activity. Chymotrypsin, a major member of the serine protease family, was used in our study to investigate whether it has a similar function. Optical absorbance, broth microdilution and scanning electron microscopy (SEM) assays were carried out to investigate the direct effect of chymotrypsin on bacteria. A disk diffusion test and LC-MS spectrometry were then used to investigate the effect of chymotrypsin on antibacterial activity of ampicillin. Chymotrypsin exhibited potentially antimicrobial properties to two kinds of Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis). However, the existence of chymotrypsin could also hinder the antibacterial activity of ampicillin, in part because chymotrypsin could degrade ampicillin in a dose-dependent manner. These results could be helpful in guiding current commercial usages of chymotrypsin and devising better strategies of clinical applications.

The complete sequence of transferrin has been cloned from cypermethrin-resistant strain of Culex pipiens pallens(Cr-C strain). Quantitative reverse transcription PCR analysis indicated that the transferrin transcription level was 12.6 times higher in Cr-C strain than in susceptible strain at fourth instar larvae. The transferrin expression was also found to be consistently higher throughout the life cycle of Cr-C strain. A protein of predicted size 90.8 kDa has been detected by Western blotting in transferrin-transfected mosquito C6/36 cells. These transferrin-transfected cells also showed enhanced cypermethrin resistance compared to null-transfected or plasmid vector-transfected cells as determined by methyl tritiated thymidine((3)H-TdR) incorporation. These results indicate that transferrin is expressed at higher levels in Cr-C strain and may confer some insecticide resistance in C. pipiens pallens.

Delineating neurons that underlie complex behaviors is of fundamental interest. Using adeno-associated virus 2, we expressed the Drosophila allatostatin receptor in somatostatin (Sst)-expressing neurons in the preBötzinger Complex (preBötC). Rapid silencing of these neurons in awake rats induced a persistent apnea without any respiratory movements to rescue their breathing. We hypothesize that breathing requires preBötC Sst neurons and that their sudden depression can lead to serious, even fatal, respiratory failure.