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Charge density wave (CDW) as a novel effect in two-dimensional transition metal dichalcogenides (TMDs) has obtained a rapid rise of interest for its physical nature and potential applications in oscillators and memory devices. Here, we report var der Waals epitaxial growth of centimeter-scale 1T-VTe2 thin films on mica by molecular beam epitaxy. The VTe2 thin films showed sudden resistance change at temperatures of 240 and 135 K, corresponding to two CDW phase transitions driven by temperature. Moreover, the phase transitions can be driven by an electric field due to local Joule heating, and the corresponding resistance states are nonvolatile and controllable, which could be applied to the memory device where the logic states can be switched by an electric field. The multistage CDW phase transitions in the VTe2 thin films could be contributed to electron–phonon coupling in the two-dimensional VTe2, which is supported by twice pronounced Raman blue shifts of the vibration modes associated with in-plane phonons at CDW phase transition temperature. The results open up a new platform for understanding the microscopic physical essence and electrical control of CDW phases of TMDs, expanding the functionalities of these materials for memory applications.

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Objectives This study aimed to explore the reporting of workplace violence against nurses and the reasons why they did not reported. Methods A self-designed questionnaire regarding workplace violence and reporting was used to conduct a cross-sectional survey on nurses who submitted a manuscript to a Chinese nursing journal from 2016 to 2017. A total of 324 nurses agreed to participate in this study and 266 participants from 165 hospitals in 72 cities returned questionnaires. Results A total of 172 nurses (64.7%) experienced violent incidents during the past year. Of these incidents, 45.5% were reported; and the reporting rate of physical assaults (69.0%) was higher than those of verbal abuse (36.9%), threatening behavior (51.7%), and sexual harassment (60.0%). Formal reporting accounted for 25.4% (15.4% in written form and 10.0% through a computer-assisted reporting system). Almost half of the nurses (49.6%) stated that the hospital had no reporting system or they were uncertain about the reporting system. For reasons of not reporting, 51.9% of the nurses were unware of how and what types of violence to report, and 50.6% of the nurses believed that the hospital paid greater attention to patients rather than staff. Conclusions A clear definition of workplace violence and reporting procedures, establishment of a facile system for reporting, and supervisory support following a reporting are urgently required.