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Skill competence is essential for nursing students and experiential teaching method has become increasingly popular in China's nursing education. To systematically evaluate the effects of experiential teaching method on the development of nursing students’ skill competence, and to provide evidence for nursing education.

Enhanced resistive switching phenomena of IrO/GdO/W cross-point memory devices have been observed as compared to the via-hole devices. The as-deposited GdO films with a thickness of approximately 15 nm show polycrystalline that is observed using high-resolution transmission electron microscope. Via-hole memory device shows bipolar resistive switching phenomena with a large formation voltage of -6.4 V and high operation current of >1 mA, while the cross-point memory device shows also bipolar resistive switching with low-voltage format of +2 V and self-compliance operation current of <300 μA. Switching mechanism is based on the formation and rupture of conducting filament at the IrO/GdO interface, owing to oxygen ion migration. The oxygen-rich GdO layer formation at the IrO/GdO interface will also help control the resistive switching characteristics. This cross-point memory device has also Repeatable 100 DC switching cycles, narrow distribution of LRS/HRS, excellent pulse endurance of >10,000 in every cycle, and good data retention of >10 s. This memory device has great potential for future nanoscale high-density non-volatile memory applications. [ABSTRACT FROM AUTHOR]

In order to reduce the high temperature of steel bridge deck pavement to improve its performance and delay its early destruction, temperature fields of steel bridge deck pavement were researched based on Fourier' s law and climatological data provided by competent meteorological departments using finite element method. Results indicate that the temperature of steel bridge deck pavement can be lowered, the duration of high-temperature action is reduced and the temperature distribution in deck pavement is changed by open steel box beam. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the outcome of endodontic microsurgery and analyze the potential prognostic factors, and to evaluate the value of surgical classification by Kim and Kratchman., Methods: Collecting clinical examination and radiographical examination of endodontic microsurgery cases (which were followed up at least 1 year), which were classified according to Kim and Kratchman, and we analyzed the outcome of endodontic microsurgery and its potential prognostic factors., Results: 302 patients (400 teeth) who received endodontic microsurgery were included. The one year success rate of endodontic microsurgery was 94.25%. Different classification had significant influences on the outcome of endodontic microsurgery ( P <0.05), and the success rate of class B and C were better than those of class D, E, and F. The position of teeth had significant influences on the outcome of endodontic microsurgery ( P <0.05). The success rate of maxillary teeth was higher than that of mandibular teeth. The success rate of anterior teeth was higher than that of posterior teeth ( P <0.05). The quality of root end filling and first or second surgery had no effect on the outcome ( P >0.05)., Conclusions: Endodontic microsurgery is an effective treatment method for saving affected teeth, and it can get a good result. Tooth position and classification are the potential prognostic factors. The surgical classification of Kim and Kratchman can help to predict the outcome of endodontic microsurgery.

Ample variations of the major histocompatibility complex (MHC) genes are essential for vertebrates to adapt to various environmental conditions. In this study, we investigated the genetic variations and evolutionary patterns of seven functional MHC class II genes (one DRA, two DRB, two DQA, and two DQB) of the giant panda. The results showed the presence of two monomorphic loci (DRA and DQB2) and five polymorphic loci with different numbers of alleles (seven at DRB1, six at DRB3, seven at DQA1, four at DQA2, six at DQB1). The presence of balancing selection in the giant panda was supported by the following pieces of evidence: (1) The observed heterozygosity was higher than expected. (2) Amino acid heterozygosity was significantly higher at antigen-binding sites (ABS) compared with non-ABS sequences. (3) The selection parameter omega (d(N)/d(S)) was significantly higher at ABS compared with non-ABS sequences. (4) Approximately 95.45% of the positively selected codons (P>0.95) were located at or adjacent to an ABS. Furthermore, this study showed that (1) The Qinling subspecies exhibited high omega values across each locus (all >1), supporting its extensive positive selection. (2) The Sichuan subspecies displayed small omega at DRB1 (omega<0.72) and DQA2 (omega<0.48), suggesting that these sites underwent strong purifying selection. (3) Intragenic recombination was detected in DRB1, DQA1, and DQB1. The molecular diversity in classic Aime-MHC class II genes implies that the giant panda had evolved relatively abundant variations in its adaptive immunity along the history of host-pathogen co-evolution. Collectively, these findings indicate that natural selection accompanied by recombination drives the contrasting diversity patterns of the MHC class II genes between the two studied subspecies of giant panda., (2009 Wiley-Liss, Inc.)