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Objective To assess and compare the performance of fluorine-18-labeled fluorodeoxyglucose positron emission tomography (18 F-FDG-PET/ CT) and gallium-68-labeled tetraazacyclododecanetetraacetic acid-DPhe1-Tyr3-octreotate (68 Ga- DOTATATE) PET/CT in the targeted imaging of culprit tumors causing osteomalacia. Methods This was a clinical retrospective analysis. We analyzed 13 patients (five men, eight women; mean age, 49 years; range, 19-55 years) with suspicion of tumor-induced osteomalacia (TIO) between March 2017 and October 2019. All patients underwent two functional imaging methods to locate the culprittumors. Studies were performed on a PET/CT scanner. The injection doses of 18 F- FDG and 68 Ga-DOTATATE were 0.5mCi/kg and approximately 5.0mCi, respectively. In the two scans, the whole body was captured from head to toe 45 to 60 min after intravenous tracer injection. 68 Ga-DOTATATE PET/CT and 18 F-FDG PET/CT imaging results locate culprit tumors according to the following criteria: (i) abnormal foci uptake concentration was observed locally, and the uptake level was higher than the background level of the right lobe of the liver; (ii) combined CT showed or did not have obvious abnormal density changes; and (iii) non-specific ingestion lesions due to fracture, arthritis, necrosis of femoral head are excluded. Compared with the results of pathological examination and clinical follow-up, the sensitivity, specificity and accuracy of 68 Ga-DOTATATE PET/CT imaging and 18 F-FDG PET/CT imaging for TIO were analyzed. Results All patients had symptoms of osteomalacia and hypophosphatemia. The lag time (symptoms to PET diagnosis) ranged from 2 to 12 years. There were eight cases of TIO patients and five cases of non-TIO patients confirmed by surgery, pathology and follow-up. Among the eight TIO patients, there were six cases (75.0%) of PMTs, one case (12.5%) of giant cell tumor, one case (12.5%) of hemangiopericutoma. Most (n = 6, 75.0%) of the confirmed tumors in our patient population were in the lower extremities, followed by craniofacial regions (n = 1, 12.5%), and torso (n = 1, 12.5%), respectively. Among the five non-TIO patients, there were two cases of Fanconi syndrome, one case of rickets, and two cases of sporadic osteomalacia hypophosphorus. The culprit tumors could be located either in the bone (n = 5, 62.5%) or the soft tissue (n = 3, 37.5%). 18 F-FDG PET/CT was able to localize the tumor in six (6/13, 46.1%) patients. 68 Ga-DOTATATE PET/CT detected tumor in 8 (83.3%) of 13 patients. The sensitivity of 68 Ga-DOTATATE PET/CT imaging and 18 F-FDG PET/CT imaging in the evaluation of TIO in our patient population were 100% (8/8) vs 75% (6/8). The specificity of the two different methods was 80% (4/5). The overall accuracy was 92.3% (12/13) vs 76.9% (10/13). Conclusions 68 Ga-DOTATATE PET/CT is very effective in assessing hypophosphatemia patients with TIO typical symptoms compared with 18 F-FDG. Therefore, in clinically suspected cases of hypophosphatemic osteomalacia, 68 Ga-DOTATATE PET/CT should be preferred as an imaging modality investigation to avoid delay in the treatment of this disease.

Structural defects and chemical impurities exist in organic semiconductors acting as trap centers for the excited states. This work presents a novel analytical model to calculate the trapping and detrapping rates between two Gaussian density of states. Miller-Abrahams rate and Fermi-Dirac statistics are employed in this model. The introduction of effective filled and empty sites for correlated bands greatly simplifies the expression of recombination rate. A technology computer-aided design simulator was used to simulate the donor-like traps in an organic semiconductor DPP-DTT based thin-film transistor, showing good agreement with the measured transfer characteristic.

The current meta-analysis was conducted aiming to explore the association between pre-therapy CRP and DLBCL survival outcomes. We retrieved previously published studies available from PubMed, EMBASE, Web of Science, The Cochrane Library, Wanfang databases, and China National Knowledge Infrastructure databases by June 2017. A total of 12 studies composed of 3000 patients were included in this study according to our selection criteria. The pooled HRs of elevated pre-therapy CRP were 2.66 (95% CI = 1.95-3.64, p

That the energy of triplet exciton in Rubrene is about half of its singlet leads to energy resonance. This resonance not only allows two triplets to annihilate into a singlet, but also makes a singlet probably fission into two triplets in different molecules. On the other hand, the π-π conjugation of two Rubrene molecules could be formed during molecules stacking, and this spatial relationship will affect the charge transport property enormously. In this article, we use organic magnetic-field effect as a convenient approach to explore the influence of the energy resonant excited states in the Rubrene molecules and the π-π conjugation between the different molecules on the luminescence property of Rubrene. Firstly, we fabricate organic light emitting diodes based on pure Rubrene and modulate the thickness of Rubrene. Experimental measurements of these devices at room temperature exhibit that the thickness can affect the devices' magneto-electroluminescence (MEL) curves substantially. Values of high-field MEL increase with the thickness of Rubrene and gradually saturate after reaching 30 nm. This can be attributed to the fact that the ratio of π-π conjugation in Rubrene molecules to the stacking will grow with increasing thickness, and then saturate at a proper thickness. Subsequently, we modulate the concentration of Rubrene by doping Buthocuproine (BCP) in the active layer. Experimental results at room temperature show that the values of high-field MEL decrease as the concentration of Rubrene decreases. These results verify that the influence of π-π conjugation is not only on the MEL curves, but also on the singlet fission. Furthermore, all the MEL curves exhibit a high-field decay at low temperatures since the endothermic fission process in the Rubrene molecules becomes weaker as the temperature decreases, and the longer triplet lifetime at lower temperatures also enhances the process of triplet annihilation. Besides, the extensively existent intersystem crossing between singlet and triplet polaron pairs may affect these devices as well. Finally, the MEL curves of 20% Rubrene device at room temperature changing with various currents are successfully fitted through the combination of two exponential functions and a Lorentzian function. By means of the fitting, we confirm that the singlet exciton fission, the triplet-triplet exciton annihilation, and the intersystem crossing between singlet and triplet polarons coexist in the devices. Therefore, the varieties of these MEL curves can be attributed to the competition of these processes. The fittings reveal that the triplet-triplet exciton annihilation rate increases more obviously than the singlet exciton fission rate with increasing current. Compared with the rates of the two bimolecular interactions given before, the change of the intersystem crossing rate could be neglected because of its small magnitude. This work is helpful to expand the understanding of the internal mechanism of organic optoelectronic devices.