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Objective·To study the alterations in vestibular hair cell morphology and function of ATPase plasma membrane Ca2+ transporting 2 oblivion (Atp2b2 Oblivion) heterozygous mice at different ages.Methods·Atp2b2 Oblivion heterozygous male mice aged 2 months and 8 months were selected with ten in each kind and C57BL/6J wild-type mice with the same gender, age and number were selected as the control group. Expression patterns of ATP2B2 in vestibular hair cells and numbers of hair cells in the striola zone and the extra striola zone in the two groups of mice at different ages were observed and calculated respectively through immunofluorescence assay. Hair bundle structures were detected by scanning electron microscopy (SEM), and mitochondria and ribbon synapse structures were observed by transmission electron microscopy (TEM). Vestibular evoked potential (VsEP), vestibular evoked myogenic potential (VEMP), rotarod rod test, and balance beam test were adopted for the evaluation of vestibular functions.Results·ATP2B2 was mainly expressed in the hair bundle of vestibular hair cells in the two groups of mice. Hair cell numbers in the striola zone and the extra-striola zone did not exhibit any differences between Atp2b2 Oblivion heterozygous mutant mice and wild-type mice of 2-month-old and 8-month-old. No visible structural abnormality in the hair bundle could be seen through SEM. TEM results implied no morphological abnormality in mitochondria or ribbon synapses in the 2-month-old heterozygous mutant mice, while vacuolar degeneration was discovered in the mitochondria under the cuticular plate in the 8-month-old heterozygous mutant mice with the normal ribbon synapses and the normal mitochondria near the innervation site. VsEP and VEMP thresholds of 2-month-old and 8-month-old Atp2b2 Oblivion heterozygous mutant mice were significantly elevated compared with the wild-type mice. Analysis of VsEP waveform manifested prolonged P1 latency and declined P1N1 amplitude in heterozygous mutant mice (P

Aiming at the problem that the sequence recommendation models based on the self-attention mechanism ignore all kinds of auxiliary information, which makes the model unable to use them to capture multi-level sequence relationship patterns, a recommendation algorithm integrating time context and feature-level information is proposed (ITFR). Firstly, the item representation is connected with each of its attribute representations and input into an attention network. After attention is weighted, an attribute-based item representation is obtained. Then, ITFR applies the self-attention block of the perception time interval and the self-attention block based on the item-attribute to capture the relationship pattern between the item and the interaction sequence time interval and the implicit relationship between the item and the attribute, respectively. Finally, the output representations of the two self-attention blocks are connected, and the joint output representation is input to the fully connected layer for the recommendation of the next item. Experiments are conducted on two public datasets, and two performance indicators of hit rate (HR) and normalized discounted cumulative gain (NDCG) are used for evaluation. In the Beauty dataset, compared with the optimal baseline method, HR@10 and NDCG@10 are increased by 4.6% and 5.1%, respectively. In the Movie-1M dataset, HR@10 and NDCG@10 are increased by 1.7% and 1.5%, respectively. Experimental results show that the method of incorporating auxiliary information to enhance sequence representation can improve recommendation performance.