Single-mode lasing of CsPbBr perovskite NWs enabled by the Vernier effect.

Inorganic lead halide perovskite (CsPbX3, X = Cl, Br, I) NWs (NWs) have been employed in lasers due to their intriguing attributes of tunable wavelength, low threshold, superior stability, and easy preparation. However, current CsPbX3 NW lasers usually work in a multi-mode modal, impeding their practical applications in optical communication due to the associated false signaling. In this work, high-performance single-mode lasing has been demonstrated by designing and fabricating coupled cavities in the high-quality single-crystal CsPbBr3 NWs via the focused ion beam (FIB) milling approach.

Ultrathin and Conformable Lead Halide Perovskite Photodetector Arrays for Potential Application in Retina-Like Vision Sensing.

Solution-processed lead halide perovskites are considered one of the promising materials for flexible optoelectronics. However, the array integration of ultrathin flexible perovskite photodetectors (PDs) remains a significant challenge limited by the incompatibility of perovskite materials with manufacturing techniques involving polar liquids. Here, an ultrathin (2.

Two Photon-Pumped Whispering-Gallery Mode Lasing and Dynamic Regulation.

Realizing the dynamic regulation of nonlinear optical signals has a great scientific significance for the development of new-type nonlinear optoelectronic devices and expands its application in the field of laser technology, spectroscopy, material structure analysis, etc. Here, two photon absorption-induced whispering-gallery mode lasing from a single ZnO microresonator with a relatively low lasing threshold (15 µW) and high quality factor ( ≈ 3200) under ambient conditions is demonstrated. Furthermore, success is achieved in obtaining the dynamic regulation of two photon-pumped lasing mode in the UV gain region.

Crystal-Orientation-Related Dynamic Tuning of the Lasing Spectra of CdS Nanobelts by Piezoelectric Polarization.

Realizing dynamic wavelength tunability could bring about tremendous impacts in laser technology, pressure nanosensing, and lab-on-a-chip devices. Here, we demonstrate an original strategy to operate the lasing mode shift through reversible length changes of a CdS nanobelt, which is determined by the direction of piezoelectric polarization. The relationships between the direction of applied strain, the lasing mode shift, and the tunable effective refractive index are elaborated in detail.

Influence of orthodontic treatment with fixed appliances on enamel color: a systematic review.

Background: The purposes of this systematic review were to identify and review the orthodontic literature with regard to enamel color alterations after orthodontic treatment with fixed appliances. The effects of clean-up procedures on the surface of enamel were also investigated.

Methods: We searched the following electronic databases: Medline (1950 to 6 July 2014), EMBASE via OVID (1980 to 6 July 2014), Google Scholar, Web of Science (1950 to 6 July 2014), CENTRAL (The Cochrane Library, 2014, Issue 7).

The effects of incisor inclination changes on the position of point A in Class II division 2 malocclusion using three-dimensional evaluation: a long-term prospective study.

Objective: The aim of this study was to evaluate change in the sagittal position of point A due to orthodontic treatment by orthodontic community-cone beam computed tomography (CBCT).

Materials And Methods: 40 subjects (22 males and 18 females) who had Class II division 2 malocclusion were recruited, and 40 subjects (23 males and 17 females) who had minor crowding in the beginning of the treatment and required no or minimal maxillary anterior tooth movement were served as control. The changes in maxillary incisor inclination, sagittal position of point A, SNA angle, and movement of incisor root apex and incisal edge were calculated before and after CBCT treatment.

Orthodontic treatment of severe anterior open bite and alveolar bone defect complicated by an ankylosed maxillary central incisor: a case report.

Incisor trauma is common in children, and can cause severe complications during adolescent growth and development. This report describes the treatment of a 16-year-old patient with severe anterior open bite due to ankylosis of the maxillary left incisor after dental trauma as an 8-year-old. No examination or active treatment was undertaken until he was 16 years old.