Investigating the Factors Governing the Efficiency and the Electroluminescence Stability in Simplified Phosphorescent Organic Light-Emitting Devices Utilizing One Material for Both Hole Transport and Emitter Host

Organic Light-Emitting Devices (OLEDs) have reached industrial maturity in display technology, since OLEDs provide salient advantages such as high brightness, fast response, wide viewing angle, mechanical flexibility, and low cost manufacturing. Due to the ability of electroluminescence (EL) from triplet excited states as well as singlet excited states, phosphorescent OLEDs (PHOLEDs) have a potential to achieve 100% internal quantum efficiency. Therefore, PHOLEDs can offer a competitive external quantum efficiency. However, the operational stability of PHOLEDs is relatively poor. Several mechanisms have been proposed to address the chemical and physical phenomena associated with intrinsic degradation of PHOLEDs, nevertheless, the reasons behind voltage rise and luminance loss accompanying PHOLEDs long term operation are not yet well understood. The state of the art p-i-n PHOLEDs offer relatively high efficiency and low efficiency roll-off. However, this technology is characterized by structure complexity. Therefore, much of the current research on PHOLEDs focuses on the development of the simplest possible and most easily processed architecture that can deliver the optimal combination of device properties. Simplified PHOLEDs, utilizing one material for both hole transport and emitter host, can be a good candidate for replacement of p-i-n technology. Simplified PHOLEDs offer higher efficiency than the p-i-n PHOLEDs , yet, their EL stability is found to be poor. In this thesis, the role of the ITO/organic interface on simplified PHOLEDs efficiency will be investigated. Furthermore, possible degradation mechanisms at the ITO/organic interface will be explored. Moreover, we will correlate degradation at the ITO/organic interface to PHOLEDs operational stability. Eventually, organic layers modifications including but not limited to emissive layer (EML) will be examined. By studying the indium tin oxide (ITO)/organic interface in simplified PHOLEDs, it was found that this interface is critical to PHOLEDs performance. The study shows that, this interface is critical to the PHOLED overall stability and is considered as one of the limiting factors of the long term operational stability of simplified PHOLEDs. The effect of optical excitation on the ITO/organic interface stability in hole-only devices was investigated. It was found that the ITO/organic interface is susceptible to exciton-induced degradation. This degradation affects the device stability severely compared to current-induced degradation. The exciton-induced degradation can be prevented by doping the hole transport layer (HTL), at the interface with an exciton quencher layer or by blocking the electrons from leaking to the ITO/organic interface that may further recombine with holes to form excitons. Further studies showed that upon combining both electrical stress and optical excitation, the device degradation is even more pronounced which is most likely due to interactions between charges and excitons. By using exciton life-time measurements, a new role of molybdenum trioxide (MoO3) in the electrical stability of PHOLEDs, as an exciton quencher layer, is introduced. Delayed EL (DEL) measurements showed that the simplified PHOLEDs are susceptible to triplet-triplet annihilation (TTA) and triplet-polaron quenching (TPQ) which might affect the operational stability of simplified PHOLEDs. Finally, EML modifications showed that the recombination zone of simplified PHOLEDs is located near the HTL/EML interface

The Value of Pharmacogenomics for White and Indigenous Americans after Kidney Transplantation

Background: There is a paucity of evidence to inform the value of pharmacogenomic (PGx) results in patients after kidney transplant and how these results differ between Indigenous Americans and Whites. This study aims to identify the frequency of recommended medication changes based on PGx results and compare the pharmacogenomic (PGx) results and patients’ perceptions of the findings between a cohort of Indigenous American and White kidney transplant recipients. Methods: Thirty-one Indigenous Americans and fifty White kidney transplant recipients were studied prospectively. Genetic variants were identified using the OneOme RightMed PGx test of 27 genes. PGx pharmacist generated a report of the genetic variation and recommended changes. Pre- and post-qualitative patient surveys were obtained. Results: White and Indigenous American subjects had a similar mean number of medications at the time of PGx testing (mean 13 (SD 4.5)). In the entire cohort, 53% received beta blockers, 30% received antidepressants, 16% anticoagulation, 47% pain medication, and 25% statin therapy. Drug–gene interactions that warranted a clinical action were present in 21.5% of patients. In 12.7%, monitoring was recommended. Compared to the Whites, the Indigenous American patients had more normal CYP2C19 (p = 0.012) and CYP2D6 (p = 0.012) activities. The Indigenous American patients had more normal CYP4F2 (p = 0.004) and lower VKORC (p = 0.041) activities, phenotypes for warfarin drug dosing, and efficacy compared to the Whites. SLC6A4, which affects antidepressant metabolism, showed statistical differences between the two cohorts (p = 0.017); specifically, SLC6A4 had reduced expression in 45% of the Indigenous American patients compared to 20% of the White patients. There was no significant difference in patient perception before and after PGx. Conclusions: Kidney transplant recipients had several drug–gene interactions that were clinically actionable; over one-third of patients were likely to benefit from changes in medications or drug doses based on the PGx results. The Indigenous American patients differed in the expression of drug-metabolizing enzymes and drug transporters from the White patients

Intercostal nerve transfer for biceps reinnervation in obstetrical brachial plexus palsy : a preferred reporting items for systematic reviews and meta-analysis for individual patient data systematic review using individualized fusion and comparison to supraclavicular exploration and nerve grafting

Introduction: The objective of this study was to search existing literature on nerve reconstruction surgery in patients with obstetric brachial plexus palsy to determine whether treatment with supraclavicular exploration and nerve grafting produced better elbow flexion outcomes compared to intercostal nerve transfer. Methods: This study was a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Individual Patient Data guidelines. A systematic search was conducted using multiple databases. An ordinal regression model was used to analyze the effect of using supraclavicular exploration and nerve grafting or intercostal nerve on elbow flexion with the two scores measured: elbow flexion Medical Research Council scores and Toronto active movements scale scores for elbow flexion. Results: A final patient database from 6 published articles consisted of 83 supraclavicular exploration and nerve grafting patients (73 patients with Medical Research Council and 10 patients with Toronto score) and 7 published articles which consisted of 131 intercostal nerve patients (84 patients with Medical Research Council and 47 patients with Toronto scores). Patients who underwent supraclavicular exploration and nerve grafting presented with an average Medical Research Council score of 3.9 ± 0.72 and an average Toronto score of 6.2 ± 2.2. Patients who underwent intercostal nerve transfer presented with an average Medical Research Council score of 3.9 ± 0.71 and an average Toronto score of 6.4 ± 1.2. There was no statistical difference between supraclavicular exploration and nerve grafting and intercostal nerve transfer when utilizing Medical Research Council elbow flexion scores (ordinal regression: 0.3821, standard error: 0.4590, p = 0.2551) or Toronto Active Movement Scale score for elbow flexion (ordinal regression: 0.7154, standard error: 0.8487, p = 0.2188). Conclusion: Regardless of surgical intervention utilized (supraclavicular exploration and nerve grafting or intercostal nerve transfers), patients had excellent outcomes for elbow flexion following obstetric brachial plexus palsy when utilizing Medical Research Council or Toronto scores for elbow flexion. The difference between these scores was not statistically significant. Type of study/Level of evidence: Therapeutic Study: Investigating the Result of Treatment/level III

PPAR agonists as effective adjuvants for COVID-19 vaccines, by modifying immunogenetics: a review of literature

Abstract Background Several coronavirus vaccine have been fast-tracked to halt the pandemic, the usage of immune adjuvants that can boost immunological memory has come up to the surface. This is particularly of importance in view of the rates of failure of seroconversion and re-infection after COVID-19 infection, which could make the vaccine role and response debatable. Peroxisome proliferator-activated receptors (PPARs) have an established immune-modulatory role, but their effects as adjuvants to vaccination have not been explored to date. Main body of the abstract It is increasingly recognized that PPAR agonists can upregulate the levels of anti-apoptotic factors such as MCL-1. Such effect can improve the results of vaccination by enhancing the longevity of long-lived plasma cells (LLPCs). The interaction between PPAR agonists and the immune system does not halt here, as T cell memory is also stimulated through enhanced T regulatory cells, antagonizing PD-L1 and switching the metabolism of T cells to fatty acid oxidation, which has a remarkable effect on the persistence of T memory cells. What is even of a more significant value is the effect of PPAR gamma on ensuring a profound secretion of antibodies upon re-exposure to the offending antigen through upregulating lipoxin B4, therefore potentially assisting the vaccine response and deterring re-infection. Short conclusion In view of the above, we suggest the use of PPAR as adjuvants to vaccines in general especially the emerging COVID-19 vaccine due to their role in enhancing immunologic memory through DNA-dependent mechanisms