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Abstract Inaccessibility of stored memory in ensemble cells through the forgetting process causes animals to be unable to respond to natural recalling cues. While accumulating evidence has demonstrated that reactivating memory-stored cells can switch cells from an inaccessible state to an accessible form and lead to recall of previously learned information, the underlying cellular and molecular mechanisms remain elusive. The current study used Drosophila as a model to demonstrate that the memory of one-trial aversive olfactory conditioning, although inaccessible within a few hours after learning, is stored in KCαβ and retrievable after mild retraining. One-trial aversive conditioning triggers protein synthesis to form a long-lasting cellular memory trace, approximately 20 days, via creb in KCαβ, and a transient cellular memory trace, approximately one day, via orb in MBON-α3. PPL1-α3 negatively regulates forgotten one-trial conditioning memory retrieval. The current study demonstrated that KCαβ, PPL1-α3, and MBON-α3 collaboratively regulate the formation of forgotten one-cycle aversive conditioning memory formation and retrieval.

A thin-film transistor (TFT) with a Ti-IGZO channel layer and Hf1-xAlxO gate dielectric is proposed to improve the performance and reliability of the device. The experimental results show that in three types of TFTs based on HfO2/IGZO, Hf1-xAlxO/IGZO and Hf1-xAlxO/Ti-IGZO gate dielectric/channel structures, the Hf0.88Al0.12O/Ti (2.0%)-IGZO TFT exhibits the best device performance with the subthreshold swing of 86 mV dec−1, field-effect mobility of 28.63 cm2∙V−1∙s−1 and on/off current ratio of 3.26 × 108. In particular, it shows a hysteresis voltage as low as 0.02 V and a threshold voltage shift after 1000 s positive/negative gate bias stress/white light illumination of 0.134 V/−0.089 V/−0.195 V, compared with 0.45 V and 0.612 V/−0.507 V/−0.657 V of the HfO2/IGZO TFT. These improvements are due to the incorporation of Ti into the IGZO channel, which reduces defect density, while adding Al to HfO2 improves surface roughness to inhibit surface scattering and charge capture during stress testing. [ABSTRACT FROM AUTHOR]

The nonstructural genes (NS1) of nine H9N2 subtype avian influenza viruses isolated from diseased chickens on different farms during 1998-2005 were amplified by RT-PCR and completely sequenced. The nucleotide and deduced amino acid sequences of NS1 genes of these isolates were compared. The results showed that NS1 genes of all H9N2 isolates contained 654 bp and encoded 217 amino acids. The homologies of the nucleotide and deduced amino sequences of the isolates were 95.4%-99.8% and 93.6%-100%, respectively. Comparison of the amino acid sequences of NS1 proteins of these isolates with other H9N2 viruses demonstrated that NS1 proteins of the nine strains had a deletion of 13 amino acid residues at the carboxyl terminus, which may be the molecule mark of the isolates in mainland China. Phylogenetic analysis revealed that the NS1 genes of these isolates fell into the same lineage and belonged to allele A. Eight out of nine isolates belonged to the CK/SH/F/98-like lineage while only Ck/HN/A3/98 strain belonged to the Ck/HK/Y280/97-like linease. All the isolates were derived from Ck/BJ/1/94 strain which was the first isolate is mainland China in 1994. The results indicated that H9N2 subtype AIV appeared differentiation following the passage of time and the viruses belonging to Ck/SH/F/98-like acquired an epidemic spread advantage in chicken population in mainland China.