High-quality and millimeter-sized perovskite single crystals of CsPbBr and CsPbBr were prepared in organic solvents and studied for correlation between photocurrent generation and photoluminescence (PL) emission. The CsPbBr crystals, which have a 3D perovskite structure, showed a highly sensitive photoresponse and poor PL signal. In contrast, CsPbBr crystals, which have a 0D perovskite structure, exhibited more than 1 order of magnitude higher PL intensity than CsPbBr, which generated an ultralow photoresponse under illumination. Their contrasting optoelectrical characteristics were attributed to different exciton binding energies, induced by coordination geometry of the [PbBr] octahedron sublattices. This work correlated the local structures of lead in the primitive perovskite and its derivatives to PL spectra as well as photoconductivity.

Improving the stability and tuning the optical properties of semiconducting perovskites are vital for their applications in advanced optoelectronic devices. We present a facile synthetic method for hybrid composites of perovskites and metal–organic frameworks (MOFs). A simple two-step solution-based method without organic surfactants was employed to make all-inorganic lead-halide perovskites (CsPbX3; X = Cl, Br, I, or mixed halide compositions) form directly in the pores of MIL-101 MOF. That is, a polar organic solution of lead halide (PbX2) was impregnated into the MOF pores to give PbX2@MIL-101, which was then subjected to a perovskite-formation reaction with cesium halide (CsX) dissolved in methanol. The compositions of the halogen anions in the perovskites can be modulated with various halide precursors, leading to CsPbX3@MIL-101 composites with X3 = Cl3, Cl2Br, Br2Cl, Br3, Br2I, I2Br, and I3 that exhibit gradual variation of band gap energies and tuned emission wavelengths from 417 to 698 nm.

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Background:Positional change affects the cuff pressure of an endotracheal tube (ETT) in treacheally intubated patients. We compared the cuff pressure of a TaperGuard ETT and a cylindrical ETT after lateral rotation of head during middle ear surgery.Methods:Fifty-two patients aged 18–70 years underwent a tympanomastoidectomy under general anesthesia were randomly allocated to receive endotracheal intubation with cylindrical (group C, n = 26) or TaperGuard ETTs (group T, n = 26). After endotracheal intubation, the ETT cuff pressure was set at 22 cmH2O in the neutral position of head. After lateral rotation of head, the cuff pressure was measured again and readjusted to 22 cmH2O. In addition, the change of distance from the carina to the tip of the ETT was measured before and after the positional change. The incidence of cough, sore throat, and hoarseness was assessed at 30 minutes, 6 hours, and 24 hours after surgery.Results:There was no difference in demographic data between groups. After lateral rotation of head, the cuff pressure significantly increased in group T (11.9 ± 2.3 cmH2O) compared with group C (6.0 ± 1.9 cmH2O) (P < 0.001). The incidence of a cuff pressure >30 cmH2O was higher in group T (96.2%) than in group C (30.8%) (P < 0.001). In addition, the degree of displacement of an ETT was greater in group T (11.0 ± 1.7 mm) than in group C (7.2 ± 2.6 mm) (P < 0.001). The overall incidences of postoperative sore throat, hoarseness, and cough at 30 minutes, 6 hours, and 24 hours after surgery were comparable between two groups.Conclusion:The cuff pressure was higher in the TaperGuard ETT than in the cylindrical ETT after positional change of head from neutral to lateral rotation. In addition, after a positional change, the extent of displacement of ETT was greater in the TaperGuard ETT than in the cylindrical ETT.

-We present a feasible modeling method to estimate the proper curvature for large-sized curved TVs. We especially focused on two factors -preference and perceived distortion -to be considered to determine the proper curvature. The preference includes a number of advantages that people expect to fulfill the possibilities of a more immersive image and sense of realism from curved display. On the other hand, the perceived distortion means the side effects that people can notice uncomfortable feeling caused by the shape of a curved one. In order to find out how two factors would be different as a number of conditions like curvature, size, and viewing angle change, a series of subjective assessments were conducted. The evaluation results show that both the preference and perceived distortion vary with the conditions considerably. We performed the statistical analysis based on the results and proposed the quantification model of proper curvature, which has higher preference and less perceived distortion, for various-sized curved TVs.Keywords -curved display, curvature. DOI # 10.1002/jsid.3481 Objective and background TV manufacturers have come out with curved TVs, which have various sizes and curvatures on the market over the last year or so. Because the field of view of a curved screen is larger than that of a flat one as shown in Fig. 1, the TV manufactures have assured that curved one can give better visual experiences.Earlier studies have reported the effect of curved screen, which seems to support the opinion of the TV manufacturers. The study of Schulte-Pelkum and coworkers 1 shows that curved screen enhances the human perception compared with a flat one. Park et al.2 conducted the ergonomic evaluation to investigate the influences of curvature on legibility and visual fatigue. The experiment results imply that curved display can lead to better legibility compared with a flat one; on the other hand, physiological visual fatigue is also induced with curved display. Shupp et al.3 presented that curved displays improve the performance of tasks over flat displays. The interesting point of these studies is that they regarded a curved display as a tool for information acquisition, not a device for entertainment like TV. However, our previous work 4 has conducted a series of evaluations to explore the preferred curvature of curved TVs in consideration of ergonomics and TV viewing conditions. The evaluations were performed using curved screens that have three sizes (65, 86, and 120 in.) and four curvatures (flat, 3000R, 4000R, and 5000R). We asked participants both positive and negative aspects that people can find out important factors from curved displays, namely, preference and perceived distortion. The results of evaluations show that preference of each curvature is not a distinct difference among the same-sized screens; on the other hand, test subject group perceived the distortion significantly as the curvature of screen increases (Fig. 2).From the experiment results, we found that not only preference but ...