Unique orientation of 1D and 2D nanoparticle assemblies confined in smectic topological defects.

New collective optical properties have emerged recently from organized and oriented arrays of closely packed semiconducting and metallic nanoparticles (NPs). However, it is still challenging to obtain NP assemblies which are similar everywhere on a given sample and, most importantly, share a unique common orientation that would guarantee a unique behavior everywhere on the sample. In this context, by combining optical microscopy, fluorescence microscopy and synchrotron-based grazing incidence X-ray scattering (GISAXS) of assemblies of gold nanospheres and of fluorescent nanorods, we study the interactions between NPs and liquid crystal smectic topological defects that can ultimately lead to unique NP orientations. We demonstrate that arrays of one-dimensional - 1D (dislocations) and two-dimensional - 2D (grain boundaries) topological defects oriented along one single direction confine and organize NPs in closely packed networks but also orient both single nanorods and NP networks along the same direction. Through the comparison between smectic films associated with different kinds of topological defects, we highlight that the coupling between the NP ligands and the smectic layers below the grain boundaries may be necessary to allow for fixed NP orientation. This is in contrast with 1D defects, where the induced orientation of the NPs is intrinsically induced by the confinement independently of the ligand nature. We thus succeeded in achieving the fixed polarization of assemblies of single photon emitters in defects. For gold nanospheres confined in grain boundaries, a strict orientation of hexagonal networks has been obtained with the 〈10〉 direction strictly parallel to the defects. With such closely packed and oriented NPs, new collective properties are now foreseen.

The Effect of Using Olive Oil and Fish Oil Prophylactic Dressings on Heel Pressure Injury Development in Critically Ill Patients.

INTRODUCTION AND AIM: Prevention of pressure injuries in patients hospitalized in intensive care units is significantly important. Therefore, in the present study, the effect of using olive oil and fish oil prophylactic dressings on the development of heel pressure injuries was investigated. METHODS: The present study was a clinical trial conducted in the intensive care unit of Shahid Beheshti Hospital, in Yasuj. Fifty patients, who were at moderate to high risk of pressure injuries development, were randomly divided into two groups based on the mean score of the Braden scale. In one group, patients' heels were dressed using olive oil prophylactic dressing, and in the other group, patients' heels were dressed using fish oil prophylactic dressing. The dressings were changed 3 times a day. Collected data were then analyzed using SPSS v16. RESULTS: No significant difference was determined in demographic variables among the two groups (p<0.05). In terms of the development of heel pressure injuries, none of the patients in the olive oil and fish oil groups had pressure injuries. CONCLUSION: There were no statistically significant differences in either treatment group related to heel pressure injuries outcomes during the 7 days observed in the study. Additionally, both dressings had the same effects. Further studies are recommended in this regard.

Effect of eye movement desensitization and reprocessing (EMDR) on severity of stress in emergency medical technicians.

Background and objectives: People working in health care centers and hospitals, especially the emergency departments, often experience severe stresses due to the nature of their jobs. The current study was aimed at determining the effect of eye movement desensitization and reprocessing (EMDR) on severity of stress of medical emergency technicians. Materials and methods: In the current field trial, 50 emergency medical technicians working in emergency medical centers were selected by convenience sampling method and randomly assigned to either the intervention or control group; each group had 25 subjects. In the intervention group, EMDR training was provided during five consecutive sessions, while in the control group the subjects did not receive any intervention. The data collection instrument in the study, in addition to the demographic questionnaire, was the Alken stress scale. Data had normal distribution and were analyzed using independent t, the Mann-Whitney, or chi-squared tests, and their within-group comparisons were performed by paired t and marginal homogeneity tests. Results: The mean score of stress before and after the intervention in the intervention and control groups was 32.2±7.8 and 33.6±13.8, respectively. However, after EMDR implementation, the intensity of stress in the intervention and control groups was 25.9±7.3 and 33±13.1, respectively and the difference between the groups was statistically significant (P<0.05). Chi-squared test showed that after the intervention, the degree of stress intensity in the experimental group was lower than that of the control group, and there was a significant difference between the groups in terms of stress intensity (P<0.05). Conclusion: The current study results indicated that EMDR technique significantly reduced the intensity of stress in the intervention group and can be helpful to control stress experienced by emergency medical staff.