A review of fused-ring carbazole derivatives as emitter and/or host materials in organic light emitting diode (OLED) applications

This review focuses on fused-ring carbazole derivatives, their molecular design, electronic and photophysical properties, and in particular their applications as the emitter and/or the host material in the emitting layer of organic light emitting diodes (OLEDs), with emphasis on recent developments. This review is timely because of the rapidly expanding research into fused-ring carbazoles, predominantly indolocarbazole, indenocarbazole, benzofurocarbazole, benzothienocarbazole and diindolocarbazole derivatives. To our knowledge this class of materials has not been reviewed previously. The appeal of fused-ring carbazoles is their extended π-electron systems with good thermal stability, tunable frontier orbital energies that enable a wide gamut (red, green, blue and white) emission colour, high photoluminescence quantum yields, and versatility for chemical functionalisation at different sites, leading to outstanding OLED efficiencies. This review is divided into sections according to the molecules’ role in OLEDs: namely, as conventional luminescent emitters – especially in the deep-blue region; as state-of-the-art hosts for phosphorescent iridium-based emitters; as thermally activated delayed fluorescence (TADF) emitters with high external quantum efficiency; and as multiresonance (MR) emitters with unprecedented high colour purity. We conclude by highlighting the challenges and the great opportunities for fused-ring carbazole derivatives in OLEDs and other optoelectronic applications

FDA Drug Regulation: Investigational New Drug Applications

The Food and Drug Administration (FDA)’s primary objective is to ensure safety. Investi­gational New Drugs (INDs) are focused mainly on safety, and therefore, if applicable, preclinical toxicology, manufacturing, and pharmacology data are very important. Take advantage of the FDA’s accelerated programs, where applicable, to expedite commercialization. Engage with the FDA early on to guide your development program and develop relation­ships with the FDA. Consider global opportunities and plan ahead to meet relevant health authority regulations. Academic institutions can offer guidance and regulatory support to faculty investigators

Does the Spine Surgeon’s Experience Affect Fracture Classification, Assessment of Stability, and Treatment Plan in Thoracolumbar Injuries?

Study Design: Prospective survey-based study. Objectives: The AO Spine thoracolumbar injury classification has been shown to have good reproducibility among clinicians. However, the influence of spine surgeons’ clinical experience on fracture classification, stability assessment, and decision on management based on this classification has not been studied. Furthermore, the usefulness of varying imaging modalities including radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) in the decision process was also studied. Methods: Forty-one spine surgeons from different regions, acquainted with the AOSpine classification system, were provided with 30 thoracolumbar fractures in a 3-step assessment: first radiographs, followed by CT and MRI. Surgeons classified the fracture, evaluated stability, chose management, and identified reasons for any changes. The surgeons were divided into 2 groups based on years of clinical experience as \u3c10 years (n = 12) and \u3e10 years (n = 29). Results: There were no significant differences between the 2 groups in correctly classifying A1, B2, and C type fractures. Surgeons with less experience hadmore correct diagnosis in classifyingA3 (47.2% vs 38.5%in step 1, 73.6% vs 60.3% in step 2 and 77.8% vs 65.5% in step 3), A4 (16.7% vs 24.1% in step 1, 72.9% vs 57.8% in step 2 and 70.8% vs 56.0%in step3) and B1 injuries (31.9% vs 20.7% in step 1, 41.7% vs 36.8% in step 2 and 38.9% vs 33.9% in step 3). In the assessment of fracture stability and decision on treatment, the less and more experienced surgeons performed equally. The selection of a particular treatment plan varied in all subtypes except in A1 and C type injuries. Conclusion: Surgeons’ experience did not significantly affect overall fracture classification, evaluating stability and planning the treatment. Surgeons with less experience had a higher percentage of correct classification in A3 and A4 injuries. Despite variations between them in classification, the assessment of overall stability and management decisions were similar between the 2 groups. © The Author(s) 2017

The Development of a Universally Accepted Sacral Fracture Classification: A Survey of AOSpine and AOTrauma Members.

Study Design Survey study. Objective To determine the global perspective on controversial aspects of sacral fracture classifications. Methods While developing the AOSpine Sacral Injury Classification System, a survey was sent to all members of AOSpine and AOTrauma. The survey asked four yes-or-no questions to help determine the best way to handle controversial aspects of sacral fractures in future classifications. Chi-square tests were initially used to compare surgeons\u27 answers to the four key questions of the survey, and then the data was modeled through multivariable logistic regression analysis. Results A total of 474 surgeons answered all questions in the survey. Overall 86.9% of respondents felt that the proposed hierarchical nature of injuries was appropriate, and 77.8% of respondents agreed that that the risk of neurologic injury is highest in a vertical fracture through the foramen. Almost 80% of respondents felt that the separation of injuries based on the integrity of L5-S1 facet was appropriate, and 83.8% of surgeons agreed that a nondisplaced sacral U fracture is a clinically relevant entity. Conclusion This study determines the global perspective on controversial areas in the injury patterns of sacral fractures and demonstrates that the development of a comprehensive and universally accepted sacral classification is possible

AOSpine—Spine Trauma Classification System: The Value of Modifiers: A Narrative Review With Commentary on Evolving Descriptive Principles

Study Design: Narrative review. Objectives: To describe the current AOSpine Trauma Classification system for spinal trauma and highlight the value of patient-specific modifiers for facilitating communication and nuances in treatment. Methods: The classification for spine trauma previously developed by The AOSpine Knowledge Forum is reviewed and the importance of case modifiers in this system is discussed. Results: A successful classification system facilitates communication and agreement between physicians while also determining injury severity and provides guidance on prognosis and treatment. As each injury may be unique among different patients, the importance of considering patient-specific characteristics is highlighted in this review. In the current AOSpine Trauma Classification, the spinal column is divided into 4 regions: the upper cervical spine (C0-C2), subaxial cervical spine (C3-C7), thoracolumbar spine (T1-L5), and the sacral spine (S1-S5, including coccyx). Each region is classified according to a hierarchical system with increasing levels of injury or instability and represents the morphology of the injury, neurologic status, and clinical modifiers. Specifically, these clinical modifiers are denoted starting with M followed by a number. They describe unique conditions that may change treatment approach such as the presence of significant soft tissue damage, uncertainty about posterior tension band injury, or the presence of a critical disc herniation in a cervical bilateral facet dislocation. These characteristics are described in detail for each spinal region. Conclusions: Patient-specific modifiers in the AOSpine Trauma Classification highlight unique clinical characteristics for each injury and facilitate communication and treatment between surgeons

Sacral Fractures and Associated Injuries.

STUDY DESIGN: Literature review. OBJECTIVE: The aim of this review is to describe the injuries associated with sacral fractures and to analyze their impact on patient outcome. METHODS: A comprehensive narrative review of the literature was performed to identify the injuries associated with sacral fractures. RESULTS: Sacral fractures are uncommon injuries that result from high-energy trauma, and that, due to their rarity, are frequently underdiagnosed and mistreated. Only 5% of sacral fractures occur in isolation. Injuries most often associated with sacral fractures include neurologic injuries (present in up to 50% of sacral fractures), pelvic ring disruptions, hip and lumbar spine fractures, active pelvic/ abdominal bleeding and the presence of an open fracture or significant soft tissue injury. Diagnosis of pelvic ring fractures and fractures extending to the lumbar spine are key factors for the appropriate management of sacral fractures. Importantly, associated systemic (cranial, thoracic, and abdominopelvic) or musculoskeletal injuries should be promptly assessed and addressed. These associated injuries often dictate the management and eventual outcome of sacral fractures and, therefore, any treatment algorithm should take them into consideration. CONCLUSIONS: Sacral fractures are complex in nature and often associated with other often-missed injuries. This review summarizes the most relevant associated injuries in sacral fractures and discusses on their appropriate management

Comments on Sweeny and Gliozzi dynamics for simulations of Potts models in the Fortuin-Kasteleyn representation

We compare the correlation times of the Sweeny and Gliozzi dynamics for two-dimensional Ising and three-state Potts models, and the three-dimensional Ising model for the simulations in the percolation prepresentation. The results are also compared with Swendsen-Wang and Wolff cluster dynamics. It is found that Sweeny and Gliozzi dynamics have essentially the same dynamical critical behavior. Contrary to Gliozzi's claim (cond-mat/0201285), the Gliozzi dynamics has critical slowing down comparable to that of other cluster methods. For the two-dimensional Ising model, both Sweeny and Gliozzi dynamics give good fits to logarithmic size dependences; for two-dimensional three-state Potts model, their dynamical critical exponent z is 0.49(1); the three-dimensional Ising model has z = 0.37(2).Comment: RevTeX, 4 pages, 5 figure

Production and digital image correlation analysis of titanium foams with different pore morphologies as a bone-substitute material

Ti foams are mesoporous structured materials that are characterized by their high surface area and interconnected porosity with a huge potential for biomedical applications. In this study, we investigated the production of titanium foams with different pore morphologies as a bone-substitute material via the addition of different amounts, shapes, and sizes of the space holder. Furthermore, we also carried out strain analysis using digital image correlation (DIC) in order to analyse the strain distribution across the porous samples. In addition, the nature of the relationship between the amount of the space holder added and final amount of porosity in the foams produced was also examined. The results demonstrated that the relationship between the space holder amount and porosity in the samples follows a complex one-phase exponential decay function in an increasing form. Our findings also suggest that the shape of the space holder does not play a significant role in dictating the porosity of the foams produced in the current study. However, the space holder’s shape does have a substantial role in dictating the mechanical properties of the foams produced, where Ti foams produced using a cubic or irregular space holder were found to have a lower yield stresses than those made with the spherical space holder

3D segmentation of intervertebral discs: from concept to the fabrication of patient-specific scaffolds

Aim: To develop a methodology for producing patient-specific scaffolds that mimic the annulus fibrosus (AF) of the human intervertebral disc (IVD) by means of combining magnetic resonance imaging (MRI) and 3D bioprinting. Methods: In order to obtain the AF 3D model from patientâ s volumetric MRI dataset, the RheumaSCORE segmentation software was used. Polycaprolactone scaffolds with three different internal architectures were fabricated by 3D bioprinting, and characterized by micro-computed tomography. Results: The demonstrated methodology of a geometry reconstruction pipeline enabled to successfully obtain an accurate AF model and 3D print patient-specific scaffolds with different internal architectures. Conclusion: The results guide us towards patient-specific IVD tissue engineering as demonstrated a way of manufacturing personalized scaffolds using patient's MRI data.The authors would like to acknowledge the financial support provided by the Portuguese Foundation for Science and Technology (FCT) through the project EPIDisc (UTAPEXPL/BBB-ECT/0050/2014), funded in the Framework of the ‘International Collaboratory for Emerging Technologies, CoLab’, UT justin|Portugal Program. FCT is also acknowledged for the PhD scholarship attributed to IF Cengiz (SFRH/ BD/99555/2014) and the financial support provided to J Silva-Correia (SFRH/BPD/100590/2014 and IF/00115/2015). JM Oliveira also thanks the FCT for the funds provided under the program Investigador FCT (IF/00423/2012 and IF/01285/2015). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.info:eu-repo/semantics/publishedVersio

Surgical Decision Making for Unstable Thoracolumbar Spine Injuries: Results of a Consensus Panel Review by the Spine Trauma Study Group

Objectives: The optimal surgical approach and treatment of unstable thoracolumbar spine injuries are poorly defined owing to a lack of widely accepted level I clinical literature. This lack of evidence based standards has led to varied practice patterns based on individual surgeon preferences. The purpose of this study was to survey the leaders in the field of spine trauma to define the major characteristics of thoracolumbar injuries that influence their surgical decision making. In the absence of good scientific data, expert consensus opinions may provide surgeons with a practical framework to guide therapy and to conduct future research. Methods: A panel of 22 leading spinal surgeons from 20 level I trauma centers in seven countries met to discuss the indications for surgical approach selection in unstable thoracolumbar injuries. Injuries were presented to the surgeons in a case scenario survey format. Preferred surgical approaches to the clinical scenarios were tabulated and comments weighed. Results: All members of the panel agreed that three independent characteristics of thoracolumbar injuries carry primary importance in surgical decision making: the injury morphology, the neurologic status of the patient, and the integrity of the posterior ligaments. Six clinical scenarios based on the neurologic status of the patient (intact, incomplete, or complete) and on the status of the posterior ligamentous complex (intact or disrupted) were created, and consensus treatment approaches were described. Additional circumstances capable of altering the treatments were acknowledged. Conclusions: Decision making for the surgical treatment of thoracolumbar injuries is largely dependent on three patient characteristics: injury morphology, neurologic status, and posterior ligament integrity. A logical and practical decision-making process based on these characteristics may guide treatment even for the most complicated fracture patterns