Occurrence of multiphoton resonances in five-level systems by large-amplitude driving fields

The multiphoton resonances are investigated in a five-level system in which two states are coupled strongly with two large-amplitude symmetric driving fields and both are periodically swept via other levels with the energy splitting E. Near the resonance condition in which the interdot charge transitions take place, the asymmetry at odd or even multiples of photon is found, being in agreement with experimental observations in GaAs and InAs double quantum dots. We calculate the transition rates with resonant traits through making all the energy levels time-dependent. Interestingly, the different behavior of resonances remains deep in the strong dephasing regime on the two driven energy levels. Because of the interaction between two fields such resonances take place at the third order of the energy level couplings for the first time and for higher orders as well. We investigate the strong detuning dependence of current steady-state and its complete agreement with the experiments based on calculating current in the spin blockade region via modeling the energy level structure double quantum dots and using numerical simulations. Finally, it is shown that the obtained results have all main features of the experimental data

Attitude of Nurses toward the Patient Safety Culture: A Cross-Sectional Study of the Hospitals in Tehran, Iran

Introduction: Patient safety is a major component of healthcare quality, which is defined as the avoidance of causing harm to patients in providing healthcare services. The present study aimed to investigate the attitude of nurses toward the patient safety culture in the teaching general hospitals affiliated to Tehran University of Medical Sciences, Iran. Materials and Methods: This cross-sectional study was conducted in 2014. Data were collected using the adapted version of the safety attitude questionnaire (SAQ). Sample size consisted of 385 nurses, who were selected randomly. In total, 325 participants completed the questionnaire. Data analysis was performed in SPSS Version 19 using descriptive statistics, t-test, and analysis of variance (ANOVA). Results:Mean age of the participants was 36.21±6.9 years, and 92% and 8% of the respondents were female and male, respectively. In terms of the occupational status, 92.1% of the participants had a contractual job or permanent official employment. Mean percentage of the positive attitude toward the patient safety culture was 59.2±18.1, 55.6±17.0, 53.8±24.2, 49.5±16.5, and 43.0±22.4 in the dimensions of management perception, teamwork, job satisfaction, safety climate, and work conditions, respectively. In addition, a significant difference was observed in the dimension of management perception and employment status of the nurses (F=4.4; P=0.01). Conclusion: According to the results, attitude of the nurses in the selected hospitals was poor toward the dimensions of the patient safety culture. Therefore, it is strongly recommended that specific training interventions be performed to enhance the work conditions and safety climate in these hospital