[Research progress on the mechanism of pain related neural pathways above the spinal cord].

Pain is a multi-dimensional emotional experience, and pain sensation and pain emotion are the two main components. As for pain, previous studies only focused on a certain link of the pain transmission pathway or a certain key brain region, and there is a lack of evidence that connectivity of brain regions is involved in pain or pain regulation in the overall state. The establishment of new experimental tools and techniques has brought light to the study of neural pathways of pain sensation and pain emotion. In this paper, the structure and functional basis of the neural pathways involved in the formation of pain sensation and the regulation of pain emotion in the nervous system above the spinal cord level, including thalamus, amygdala, midbrain periaqueductal gray (PAG), parabrachial nucleus (PB) and medial prefrontal cortex (mPFC), are reviewed in recent years, providing clues for the in-depth study of pain.

Stable Bifunctional Perylene Imide Radicals for High-Performance Organic-Lithium Redox-Flow Batteries.

The search for high-performance organic redox-active materials for non-aqueous redox-flow batteries remains a key challenge. Organic radicals and aromatic imides are two promising classes of redox-active materials with complementary advantages, such as the specific capacity, operating voltage, and stability, etc. Herein, this work reports two stable bifunctional radicals synthesized by the C-C coupling of redox-active phenoxyl radicals and perylene diimides (PDIs, 1. ) or benzo[ghi]perylene triimides (BPTIs, 2. ). The incorporation of electron-deficient PDIs or BPTIs into phenoxyl radicals is desired, to not only increase the number of redox-active groups per molecule and, thus, improve their specific capacities, but also to increase the redox potential and the stability of the phenoxyl radicals and, thus, enhances their battery voltages and cycle lives. When serving as the redox-active species in the catholyte of a non-aqueous static redox-flow battery, both radicals 1. and 2. exhibited a cooperatively enhanced performance with an unprecedented initial discharge voltage up to 3.12 V versus Li+ /Li, which is the hitherto most presentable potential for imide- and radical-based energy storage materials in redox-flow batteries.

Molecular Engineering of Perylene Imides for High-Performance Lithium Batteries: Diels-Alder Extension and Chiral Dimerization.

The search for high-performance electrode materials in organic rechargeable batteries remains a key challenge. Reported herein is a molecular structural modification of perylene imides, a promising class of redox-active electrode materials, for improved battery performance. The Diels-Alder extension of perylene imides at the lateral position led to the simultaneous incorporation of two electron-withdrawing carbonyl groups and extension of the π system, which is supposed to favor high specific capacity, operating voltage, and electronic conductivity. After the chiral dimerization of the extended species with 1,2-diaminocyclohexane, it was anticipated that the porosity and coulombic interactions with lithium ions would be promoted, which would be beneficial for fast reaction kinetics and long cycling life. As expected, in lithium batteries, the obtained chiral and π-extended tweezer, which features six imide groups and a porous solid-state network of 42.2 % accessible cell volume, was found to deliver a reversible capacity of 92.1 mA h g-1 at a charge/discharge rate of 1 C within an operating voltage window of 1.60-2.80 V versus Li+ /Li, around 75 and 50 % of which was maintained after 100 and 300 galvanostatic cycles, respectively, much better than those of unmodified species.

Further clarification of cognitive processes of prospective memory in schizophrenia by comparing eye-tracking and ecologically-valid measurements.

The aim of this study is to compare ecologically-valid measure (the Cambridge Prospective Memory Test, CAMPROMPT) and laboratory measure (eye-tracking paradigm) in assessing prospective memory (PM) in individuals with schizophrenia spectrum disorders (SSDs). In addition, eye-tracking indices are used to examine the relationship between PM and other cognitive domains in SSDs patients. Initially, the study sample was formed by 32 SSDs patients and 32 healthy control subjects (HCs) who were matched in sociodemographic profile and the performance on CAMPROMPT. An eye-tracking paradigm was employed to examine the differences in PM accuracy and key cognitive processes (e.g., cue monitoring) between the two groups. Additional 31 patients were then recruited to investigate the relationship between PM cue monitoring, other cognitive functions, and the severity of clinical symptoms within the SSDs group. The monitoring of PM cue was reflected in total fixation time and total fixation counts for distractor words. Cognitive functions were assessed using the Chinese version of the MATRICS Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was applied to assess psychopathology. SSDs patients exhibited fewer total fixation counts for distractor words and lower PM accuracy compared to HCs, even though they were priori matched on CAMPROMPT. Correlation analysis within the SSDs group (63 cases) indicated a negative correlation between PM accuracy and PANSS total score, and a positive correlation with working memory and attention/vigilance. Regression analysis within the SSDs group revealed that higher visual learning and lower PANSS total scores independently predicted more total fixation counts on distractor words. Impairment in cue monitoring is a critical factor in the PM deficits in SSDs. The eye-tracking laboratory paradigm has advantages over the ecologically-valid measurement in identifying the failure of cue detection, making it a more sensitive tool for PM deficits in patients with SSDs.

[Rapid determination of five halobenzoquinones in aquatic products by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry].

Halobenzoquinones (HBQs), which are emerging chlorinated disinfection byproducts (DBPs), have attracted increasing attention because they are frequently detected in treated tap water, entrainment water, etc. These compounds are mainly generated during the water treatment process using chlorine, chloramine, and chlorine dioxide as disinfectants, and display more toxic effects than regulated DBPs, such as trihalomethane and haloacetic acid. HBQs have been recognized as potential bladder carcinogens and are harmful to the nervous system. Additionally, they can exert genotoxic effects and cause oxidative damage to DNA and proteins. The risk of HBQs in aquatic products is expected to rise because the disinfection of public facilities has significantly increased in recent years. Therefore, developing a sensitive and accurate analytical method to detect HBQs in aquatic products is of great importance. Several analytical methods, including gas chromatography, gas chromatography-mass spectrometry, electrochemical methods, liquid chromatography, and liquid chromatography-tandem mass spectrometry, can be used to identify and quantify HBQs in water. However, to the best of our knowledge, no reports on the determination of HBQ levels in aquatic products are yet available. Further, pretreatment is essential for HBQ determination because of the complex matrix effects of aquatic products. Herein, a sensitive and accurate method based on the QuEChERS technique coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of five HBQs in aquatic products. For the QuEChERS procedure, the pretreatment conditions, such as the extraction solvent and adsorbent species, were systematically optimized. The sample was extracted with 10 mL of 10% methanol acetonitrile solution (containing 0.1% formic acid), dehydrated, and centrifuged with sodium chloride and anhydrous magnesium sulfate. The supernatant was purified using a QuEChERS packing material consisting of 50 mg N-propylethylenediamine (PSA), 30 mg of graphitized carbon black (GCB), and 30 mg of neutral alumina (Al2O3), dried with nitrogen, and concentrated. The five HBQs were separated on a Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm) using 0.25% acetonitrile formate solution and 0.25% formic acid aqueous solution as the mobile phase under a gradient elution program and then detected using UPLC-MS/MS with negative electrospray ionization (ESI-) under multiple reaction monitoring (MRM) mode. Quantitative analysis was performed using a matrix-matched external standard method. The five HBQs achieved rapid separation within 6 min, indicating that the proposed method has a much shorter separation time compared with previous studies. The matrix effect was evaluated by establishing a matrix-matched calibration curve. The results showed that 2,5-dichloro-1,4-benzoquinone (2,5-DCBQ) presented a matrix-enhancing effect, whereas the other HBQs displayed matrix-inhibiting effects. In particular, tetrachlorobenzoquinone (TCBQ) exhibited strong inhibitory effects. Under the optimized experimental conditions, the five HBQs demonstrated good linear relationships in the range of 1.0-50.0 µg/L, with correlation coefficients (r)≥0.9992. The detection limits of the method were 0.15-0.8 µg/kg, and the recoveries of the target compounds were 85.9%-116.5%. The relative standard deviations were 1.4%-8.2%, which indicates good reproducibility. The proposed method was successfully applied to actual sample detection, and 2,6-dichloro-3-methyl-1,4-benzoquinone (2,6-DCMBQ) was detected in grass carp. The proposed method is convenient, sensitive, accurate, and suitable for the simultaneous determination of five HBQs in aquatic products. Moreover, the developed method provides a reliable reference for the routine monitoring of trace HBQs in food samples.

EMDR versus waiting list in individuals at clinical high risk for psychosis with post-traumatic stress symptoms: A randomized controlled trial.

BACKGROUND: Post-traumatic stress disorder (PTSD) is highly prevalent in the individuals at clinical-high risk for psychosis (CHR). The aim of this study was to examine the efficacy and safety of Eye Movement Desensitization and Reprocessing (EMDR) in individuals at CHR with comorbid PTSD or subthreshold PTSD in a randomized controlled trial. METHODS: Fifty-seven individuals at CHR with PTSD or subthreshold PTSD formed the study sample. The eligible participants were randomly assigned to a 12 weeks EMDR treatment (N = 28) or a waiting list condition (WL, N = 29). The structured interview for psychosis risk syndrome (SIPS), the clinician administered post-traumatic stress disorder scale (CAPS) and a battery of self-rating inventories covering depressive, anxiety and suicidal symptoms were administered. RESULTS: Twenty-six participants in the EMDR group and all the participants in the WL group completed the study. The analyses of covariance revealed greater reduction of the mean scores on CAPS (F = 23.2, Partial η2 = 0.3, P < 0.001), SIPS positive scales (F = 17.8, Partial η2 = 0.25, P < 0.001) and all the self-rating inventories in the EMDR group than in the WL group. Participants in the EMDR group were more likely to achieve remission of CHR compared to those in the WL group at endpoint (60.7 % vs. 31 %, P = 0.025). CONCLUSIONS: EMDR treatment not only effectively improved traumatic symptoms, but also significantly reduced the attenuated psychotic symptoms and resulted in a higher remission rate of CHR. This study highlighted the necessity of adding a trauma-focused component to the present approach of early intervention in psychosis.

[Determination of kojic acid in fermented foods by solid-phase extraction coupled with ultra performance liquid chromatography-tandem mass spectrometry].

Kojic acid naturally appears in fermented foods and can be formed during the aerobic fermentation process induced by Aspergillus and Penicillium fungi. It is widely used in the food industry because it exhibits antibacterial and antifungal properties and does not affect food taste. However, recent studies indicate that kojic acid may be a potential carcinogen. Therefore, assessing the health risks of kojic acid in fermented foods are of great importance, and developing a sensitive and accurate analytical method for this compound is a significant endeavor. Much efforts have been devoted to the detection of kojic acid using electrochemistry, high performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). HPLC and HPLC-MS/MS are the analytical techniques most often employed for this purpose. Of these two methods, HPLC-MS/MS displays excellent sensitivity and is the optimal selective technique. Pretreatment is usually necessary for kojic acid determination because of the complex matrix effects of fermented foods. However, few researches on the determination of kojic acid in food are available, and, to the best of our knowledge, the determination of kojic acid using solid-phase extraction (SPE) pretreatment has not been reported yet. Herein, a convenient, sensitive, and accurate method was developed to determine kojic acid in fermented foods using solid-phase extraction-ultra performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS). The pretreatment conditions, such as the extraction solvent, cartridge, rinse solvent, and eluent, were systematically optimized. The samples, including soy sauce, vinegar, liquor, sauce, fermented soya bean, and fermented bean curd, were extracted with 0.1% formic acid-absolute ethyl alcohol and purified using a PRiME HLB cartridge. Kojic acid was separated using an ACQUITY UPLC® BEH C18 column (100 mm×2.1 mm, 1.7 µm) with formic acid-acetonitrile (1∶999, v/v) and formic acid-5 mmol/L ammonium acetate (1∶999, v/v) solutions as the mobile phases under gradient elution mode. MS was performed in electrospray positive ionization (ESI+) and multiple reaction monitoring (MRM) modes. An internal standard method was used for quantification. Under optimized conditions, good linearity was achieved at mass concentrations of 5.0-100.0 µg/L, with a correlation coefficient (r) of 0.9994. The limits of detection and quantification of the method for kojic acid were 2-5 µg/kg and 6-15 µg/kg, respectively. Good recoveries of 86.8%-111.7%, intra-day precisions of 1.0%-7.9% (n=6), and inter-day precisions of 2.7%-10.2% (n=5) were also obtained. The matrix effect was evaluated by establishing a matrix-matching calibration curve, and weak inhibitory effects were found in vinegar and liquor; moderate inhibitory effects in fermented bean curd, fermented soya bean, and soy sauce; and a strong inhibitory effect in sauce. The developed method was used to detect kojic acid in 240 fermented foods, and the results showed that the detection rate of vinegar was the highest, followed by liquor, sauce, soy sauce, fermented soya bean, and fermented bean curd, the contents were 5.69-2272 µg/kg. Matrix interferences can be significantly reduced by optimizing the pretreatment and detection procedures. The proposed method is sensitive, accurate, and can be used to analyze kojic acid in fermented foods.

The deficient cue monitoring and the facilitating effect of prosocial intention on prospective memory in patients with schizophrenia spectrum disorders.

The study aimed to investigate the cognitive processing of prospective memory (PM) in patients with schizophrenia spectrum disorders (SSDs) by using an eye-tracking paradigm. In addition, the facilitating effects of prosocial intention (the desire to help others) on PM in SSDs were also examined. In phase 1, 26 patients (group1) and 25 healthy controls (HCs) were compared in an eye-tracking PM paradigm in terms of the PM accuracy and eye-tracking indices. In phase 2, 21 more patients (group2) were recruited, and a prosocial intention was introduced in the eye-tracking PM paradigm. Their PM accuracy and eye-tracking indices were compared with those in group1. The PM cue monitoring was indicated by the total fixation counts and fixation time on distractor words. In phase 1, group1 showed lower PM accuracy, fewer fixation counts and less fixation time on distractor words than HCs. In phase 2, group2 (with prosocial intention) performed significantly better than group1 (with typical instruction) on both PM accuracy and fixation time on distractor words. In both groups of SSDs, the PM accuracy was significantly correlated with both the fixation counts and the fixation time of distractor words. After controlling for the cue monitoring indices, the difference in PM accuracy remained significant between group1 and HCs but disappeared between group1 and group2. The cue monitoring deficit contributes to the PM impairment in SSDs. The facilitating effect of prosocial intention disappears after the control of cue monitoring, also indicating its critical role in PM.

[Revision total hip arthroplasty using a cementless prosthesis].

OBJECTIVE: To assess the operative technique and results with the usage of cementless prosthesis in hip revision. METHODS: Retrospective study was done on revision of total hip arthroplasty with cementless prosthesis in 72 patients (41 males and 31 females) with an average age of 65.7 years (28-82 years) from January 2004 to December 2009. The reason for revision was 2 infection, 54 aseptic loosening, 4 periprosthetic fractures, 5 fracture of femoral stems and 7 cases of acetabular abrasion after hemi-arthroplasty. The operation time, bleeding loss, complications of infection, dislocation, periprosthetic fractures and loosening were evaluated. The Harris score were used for hip function evaluation. RESULTS: The average operation time was (146±47) minutes (70-280 minutes) and bleeding loss during the operation was (970±540) ml (200-2500 ml). Bacterium cultivation during operation demonstrated infection in 2 patients. Bone windows at the lateral femoral were opened in 4 patients and extend trochanteric osteotomy was done in 7 patients. Fracture of the proximal femur occurred in 8 cases. Twenty-nine patients were treated with bone graft including 18 autografts and 11 allografts. Sixty-seven patients were followed up for an average time of 66 months (20-92 months). Additional revisions were performed in 3 cases including 2 dislocations and 1 infection. There were no death, no damage of major blood vessels and nerves. The bone graft healed during 3-5 months. The survival rates of the femoral prosthesis and the acetabulum prostheses were 95.5% and 98.4%. The mean Harris score was 86±8 (55-95 points). Osteolysis were seen in 13 hips but migration was seen in only 1 patient. CONCLUSIONS: The cementless prosthesis is useful in revision total hip arthroplasty and the perfect clinical results are related to the reliable primary fixation.

The Unique Contribution of Past Bullying Experiences to the Presence of Psychosis-Like Experiences in University Students.

Objectives: Both bullying and psychosis-like experiences (PLEs) have gained much attention in recent years, but their interactions are not fully unraveled. The aim of the current study was to validate the Chinese version of Bullying Scale for Adults (C-BSA), and to investigate whether past bullying experiences independently predict the presence of PLEs in university students. Methods: The validity and reliability of the C-BSA were determined in two independent samples. A battery of psychological inventories was also administered to assess the presence of PLEs, maltreatment history in the family, and current depression and anxiety, including the 15-item positive subscale of the community assessment of psychic experiences (CAPE-p15), the Chinese version of the Childhood Trauma Questionnaire (CTQ), Self-Rating Depression Scale (SDS), and Self-Rating Anxiety Scale (SAS). Results: In the construction sample (N = 629), a Cronbach's α of 0.921 indicated a good internal consistency of C-BSA. The exploratory factor analysis (EFA) yielded a four-factor model and a three-factor model, and both were verified by using the confirmatory factorial analysis (CFA) in the validation sample (N = 629). The total scores of C-BSA were significantly correlated with that of CTQ, CAPE-p15, SDS, and SAS. Multivariate logistic regression revealed that bullying was associated with 2.0 or 3.7 times of risk for the presence of PLEs (numbers of bullying types < = 3 or > 3, respectively) after controlling for CTQ, SDS, and SAS scores. Conclusions: C-BSA has shown good psychometric properties in college students. The contribution of past bullying experiences to the present PLEs seems to be independent of other childhood trauma, current depression, and anxiety.

Association between deep vein thrombosis and the temperature at the popliteal fossa during cement curing in total knee arthroplasty.

The temperature at the popliteal fossa during cement curing and its relationship with deep vein thrombosis (DVT) in total knee arthroplasty (TKA) has not been investigated. Fifty-six consecutive patients who underwent primary TKA were recruited. The temperatures at the popliteal fossa were measured during bone cement exothermic polymerization. Postoperative operated leg ascending venographies were performed 5 days after TKA for screening of DVT. The maximum temperatures were 32.5°C ± 1.0°C at the popliteal fossa during cement curing. No significant difference was found of the maximum temperatures in the popliteal fossa between the non-DVT and DVT groups. The present study indicated that the heat resulting from polymerization of the cement may not be a possible cause of damage to the veins surrounding the knee, and it may have no relationship with DVT.

Performance of age-adjusted D-dimer values for predicting DVT before the knee and hip arthroplasty.

PURPOSE: To compare the specificity and sensitivity of preoperative D-dimer and age-adjusted D-dimer value for predicting the incidence of the DVT preoperatively in total joint arthroplasty (TJA) patients. METHODS: We enrolled 406 patients finally above 50 years old. Everyone had done ultrasonography bedside, and D-dimer concentrations were collected before surgery. The D-dimer and age-adjusted D-dimer cut-off was calculated by multiple logistic regression and receiver operating curve (ROC) analyses. RESULTS: A total of 39 patients had found asymptomatic deep vein thrombosis (DVT) by ultrasonography. The age (odds ratio [OR] 1.067; p = 0.003) and D-dimer (OR 1.331; p = 0.025) were related to the existence of DVT. For conventional D-dimer and age-adjusted D-dimer value, the area under the curves (AUCs) were 0.685 (0.499-0.696) and 0.795 (0.611-0.881), respectively. CONCLUSION: Compared to traditional D-dimer, age-adjusted D-dimer showed better performance in screening DVT, which was useful clinically.

Extracorporeal shock wave treatment in nonunions of long bone fractures.

We reviewed the clinical results of the past 7 years in order to investigate the effect of extracorporeal shock wave therapy (ESWT) in nonunions of long bone fracture. Sixty-nine patients with 69 nonunions (22 femora, 28 tibiae, 13 humeri, 5 radii, and 1 ulna) were treated with extracorporeal shock waves. The technical parameters were 6,000 to 10,000 impulses at 28 kV (0.62 mJ/mm(2) energy flux density) for the femur and tibia, 4,000 impulses at 24 kV for the humerus (0.56 mJ/mm(2) energy flux density), and 3,000 impulses at 24 kV (0.56 mJ/mm(2) energy flux density) for the radius and ulna. Sixty-six patients were followed up. The total successful rate of bony union was 75.4%. ESWT was successful in hypertrophic nonunions and seemed to have no evident effect in atrophic nonunions. We believe that extracorporeal shock wave therapy may be a good choice for nonunions of long bone fracture especially in hypertrophic nonunions.

Anion-π interactions in lithium-organic redox flow batteries.

The anions in electrolytes are the carriers of lithium ions for lithium-organic redox flow batteries. Herein, we reported that the interactions between the electrolyte anions and electron-deficient redox-active organic molecules (anion-π interactions) have strong influences on the battery properties due to the anion-π-induced formation of radical anions or sandwich-like aggregates.

[Effects of intra-articular injection of p38 mitogen-activated protein kinase inhibitor on matrix metalloproteinase in articular cartilage of a rat model of osteoarthritis].

OBJECTIVE: To observe the effect of intra-articular injection of SB203580, a selective p38 mitogen-activated protein kinase inhibitor, on the expression of matrix metalloproteinase (MMP)-3, MMP-13 in a rat model of osteoarthritis (OA) and to explore the relationship between the MMP-3/MMP-13 expressions and the severity of OA. METHODS: Fourty SD rats underwent unilateral anterior cruciate ligament transection (ACLT) and then randomly divided into four groups, with 10 rats in each group. Group A received 0.1 ml intra-articular injection of SB203580 at a high concentration of 100 micromol/L (once a week) immediately after surgery, and group B were treated under the same condition using SB203580 with a low concentration of 10 micromol/ L Group C received 0.1 ml intra-articular normal saline, and group D were not injected as controls after ACLT. All rats were sacrificed seven weeks after the surgery. Macroscopic and immunohistochemical studies were performed on the cartilage. Protein expressions of MMP-3 and MMP-13 were determined by Western blot. RESULTS Cartilage degradation was significantly milder in group A and group B than in the control groups, as shown by morphological studies (P < 0. 05) and immunohistochemical studies (P < 0. 05). The protein expressions of MMP-3 and MMP-13 in cartilage were significantly lower in groups A and B than in groups C and D (P < 0.01). CONCLUSION: SB203580 can inhibit the expressions of MMP-3 and MMP-13 and thus protect the cartilage.

Research on the Determination of 10 Industrial Dyes in Foodstuffs.

An efficient method was developed for the simultaneous determination of 10 industrial dyes (basic orange 2, basic orange 21, basic orange 22, acid orange II, auramine, basic rhodamine B and Sudan I-IV) in the foodstuffs using high-performance liquid chromatography coupled with diode array detector. Samples were extracted with acetonitrile and cleaned up on a solid phase extraction cartridge using HLB. The chromatographic separation was achieved on a C18 column using a mobile phase consisting of methanol and 10 mmol/L ammonium acetate with 0.1% formic acid by gradient elution. Good linearity (r ≥ 0.9993) was observed between 0.050 and 5.0 µg/mL. The limits of detection were in the range of 0.007-0.01 mg/kg, high recoveries (80.6-104%) and good reproducibility (1.1-5.7%) were obtained. Such method is simple, feasible and accurate, which can be applied to the quantification of 10 dyes in food samples.

[Arthroscopic treatment of tibial intercondylar eminence avulsion fractures using no absorbable suture fixation].

OBJECTIVE: To study the surgical skill and the clinical outcomes of arthroscopic treatment of tibial intercondylar eminence avulsion fractures using no absorbable suture fixation. METHODS: A total of 30 cases with avulsion fractures of the tibial intercondylar eminence were treated with no absorbable suture fixation from January 2001 to December 2004. All procedures were performed arthroscopically by the same surgeons. There were 8 cases of type II, 17 type III, 5 type IV based on the Meyers and McKeever classification and 26 cases were fresh fracture. The procedure was completed with the assistance from No. 18 spine needle and Kirschner wire (Ø2.0 mm and Ø1.0 mm) and director drill guide. Postoperative immobilization was not required. RESULTS: All patients were followed up for 3 to 24 months, average (15.0 +/- 4.7) months. Subjective results of all cases were uniformly excellent. The mean Lysholm score was 98.4 in 18 cases of fresh fracture, and 89.8 in 4 cases of old fracture. Mean KT2000 side-to-side difference was normal in all case. CONCLUSIONS: The technique is simple, safe, reproducible, minimal invasion and effective; postoperative immobilization is not required; knee joint function is excellent.

Isomeric Thermally Activated Delayed Fluorescence Emitters for Color Purity-Improved Emission in Organic Light-Emitting Devices.

To improve the color purity of thermally activated delayed fluorescence (TADF) emitters, two isomeric compounds, oPTC (5'-(phenoxazin-10-yl)-[1,1':3',1″-terphenyl]-2'-carbonitrile) and mPTC (2'-(phenoxazin-10-yl)-[1,1':3',1″-terphenyl]-5'-carbonitrile), were designed and synthesized with same skeleton but different molecular restrictions. Both compounds exhibit similar highest occupied molecular orbital and lowest unoccupied molecular orbital distributions and energy levels, photophysical properties in nonpolar cyclohexane solution, and high external quantum efficiencies (19.9% for oPTC and 17.4% for mPTC) in the devices. With the increased molecular space restriction induced by the additional phenyl substitutions at meta-position of the cyano group from mPTC to oPTC, much weaker positive solvatochromic effect is observed for mPTC. And the color purity of emission from mPTC (full width at half-maximum (fwhm) of 86 nm) is also improved contrasted with that of oPTC (fwhm of 97 nm) in the devices. These results prove that increased restriction of the molecular structure is a simple and effective method to improve the color purity of the TADF emitters.

High Performance All Fluorescence White Organic Light Emitting Devices with a Highly Simplified Structure Based on Thermally Activated Delayed Fluorescence Dopants and Host.

Thermally activated delayed fluorescence (TADF) emitters of different colors commonly need different hosts, which cause the complexed device structure and low efficiency of all fluorescence white organic light-emitting devices (F-WOLEDs). To solve this, novel concept of employing TADF exciplex as universal host of TADF emitters with different colors was proposed. All blue, green, and orange devices based on the TADF exciplex host show much lower turn-on voltages, and comparable and even higher efficiencies than corresponding devices based on conventional hosts. The two color F-WOLED with extremely simplified device structure was finally fabricated, achieving a white emission with the maximum current efficiency (CE), power efficiency (PE), and external quantum efficiency (EQE) respectively of 50.1 cd A-1, 63.0 lm W-1, and 19.0% in the forward-viewing direction without any light out-coupling technology, which is the best performance among reported F-WOLEDs, demonstrating the superiority of the novel concept.