9 research outputs found
Charge transport mechanisms in monovalent doped mixed valent manganites
Abstract In this communication, we report the results of the studies on structural and transport properties of monovalent Na + doped La 1-x Na x MnO 3 (LNMO; x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) manganites synthesized by conventional ceramic method. X-ray diffraction (XRD) and Rietveld refinements reveal the single phasic nature of LNMO manganites without any detectable impurity within the measurement range. Temperature dependent resistivity, under different applied magnetic fields, has been performed on LNMO samples. Samples understudy exhibit metal to insulator (semiconductor) transition at temperature T P which is strongly influenced by the substitution of Na + at La 3+ site. -T plots also exhibit resistivity upturn behavior at low temperature well below 40K under all the applied fields. Variation in T P and resistivity has been discussed in the context of the competition between the transport favoring tolerance factor and zener double exchange (ZDE) mechanism and transport degrading Jahn-Teller (JT) and size variance effects. In order to understand the mechanisms responsible for the charge transport in metallic and semiconducting regions and to explore the possible electronic processes responsible for the observed low temperature resistivity minima in all the presently studied LNMO manganites, various models have been employed. It has been found that VRH mechanism gets successfully fitted to the resistivity data in the semiconducting region while ZDE polynomial law is responsible for the charge conduction in metallic region for all the presently studied LNMO samples. A strong dependence of activation energy on the Na + -content as well as applied magnetic field has been discussed in the context of variation and interrelations between the structural parameters. Charge conduction in metallic region has been discussed in the light of electron-phonon interactions which is influenced by the Na + -content and applied magnetic field. Electrostatic blockade model has been employed to understand the low temperature resistivity minima behavior. Blocking energy for the charge carriers shows a dependence on the magnetic energy provided to the charge carriers. Present study can be useful to understand and to control the charge conduction in the manganites and hence to design the manganite based thin film devices for various spintronic applications
Impact of Intensive Care Unit Discharge Delay on Liver Transplantation Outcomes
Background: For general intensive care unit (ICU) patients, ICU discharge delay (ICUDD) has been associated with an increased hospital length of stay (LOS) and the acquisition of multi-resistant organism (MRO) infections. The impact of ICUDD on liver transplant (LT) recipients is unknown. Methods: We retrospectively studied consecutive adult LT between 2011 and 2019. ICUDD was defined as >8 h between a patient being cleared for discharge to ward and the patient leaving the ICU. Results: 550 patients received LT and the majority (68.5%) experienced ICUDD. The median time between clearance for ward and the patient leaving the ICU was 25.6 h. No donor or recipient variables were associated with ICUDD. Patients cleared for discharge early in the week (Sunday-Tuesday) and those discharged outside routine work hours were more likely to experience ICUDD (p = 0.001 and p < 0.001, respectively). The median hospital LOS was identical (18 days, p = 0.96) and there were no differences in other patient outcomes. Patients who became colonized with MRO in the ICU spent a longer time there compared to those who remained MRO-free (9 vs. 6 days, p < 0.001); however, this was not due to ICUDD. Conclusion: ICUDD post-LT is common and does not prolong hospital LOS. ICUDD is not associated with adverse patient outcomes or MRO colonization
Adolescents and young adults communicating with gastroenterologists: Variation in inflammatory bowel disease clinical communication
Objectives: This study explored the variation in emerging adults\u27 communication with gastroenterologists around the management of inflammatory bowel disease (IBD). Methods: Nineteen emerging adults with IBD aged 18-25 and seven gastroenterologists participated in the study. Outpatient specialist consultations of consenting participants were audio-recorded and transcribed. Transcribed consultations were analysed in terms of the linguistic structure of the consultations and the gastroenterologist-patient role relationship. Results: Variations in the emerging adults\u27 communication with their gastroenterologists stem partly from variation in their ability, opportunity, or need to contribute to the different phases of the consultation and partly from variations in the gastroenterologists\u27 style of communication. Gastroenterologists differed in the construction of their role relationship with the patient, resulting in variations in employing empowering strategies including eliciting, exploring, and clarifying the patient\u27s concerns, sharing clinical reasoning, and validating the patient experience. Variations were also observed in the length of appointments and the gastroenterologists\u27 assessment and addressing of adherence issues. Techniques used by the gastroenterologist varied (1) from simply confirming adherence, to a comprehensive assessment of the patient\u27s understanding of their management plan and their feedback, and (2) from use of persuasion to values calibration. Conclusions: Evidence-based consumer interventions and communication guidelines for clinicians are needed to address the identified variations in providing care to emerging adults living with chronic conditions