Metal halide perovskite light-emitting diodes (PeLEDs) have gained significant interest for next-generation optoelectronic devices, since PeLEDs exhibit narrow emission bandwidth that allows for vivid and clear images based on their high color purity. [1][2][3][4][5][6] The emission color of PeLEDs is tunable in the visible and near-infrared (NIR) spectral regions and they offer low operating and turn-on voltages, along with promising efficiency values. [3,4,[7][8][9] In addition, thin films have shown nearunity photoluminescence quantum yield (PLQY) and population inversion at room temperature, [10][11][12][13][14] potentially allowing for electrically pumped lasers with various emission colors.There has recently been rapid growth in the external quantum efficiency (EQE) of PeLEDs, to values of over 20%, [9,[15][16][17][18][19][20][21][22][23][24][25][26][27] since early reports of PeLEDs in 2014 with efficiency below 0.25%. [28] Numerous strategies to improve the EQE of PeLEDs are being actively pursued in order to bring their performance in line with other, more established, LED technologies. [8] However, a disparity of refractive index (n) between organic transport layers (typically in the range of 1.6-1.8) and the perovskite emissive layer (≈2.3 near the emission wavelength) holds back performance. [29][30][31][32] Due to the high n of the perovskite layer, the maximum EQE of PeLEDs is limited by outcoupling efficiency and restricted to ≈20%, with the remainder of light being trapped within the thin film and substrate materials, as well as parasitic absorption. [31,32] Therefore, it is necessary to investigate alternative device architectures that are able to enhance outcoupling efficiency and realize direct benefits to EQE.In this study, we demonstrate EQE of 14.6% in methylammonium lead iodide (MAPbI 3 ) based red/NIR LEDs using a randomly distributed nanohole array (NHA) embedded in a SiN layer between the indium tin oxide (ITO) anode and glass substrate. The SiN layer with a high n of 2.02 at the peak emission wavelength possesses a high-index contrast with the voids of the NHA with n of 1.0. This layer effectively compensates for the high n of the perovskite emissive layer and aids outcoupling of waveguided and substrate modes. As a result, PeLEDs with NHAs show 1.64 times higher light extraction than PeLEDs without NHAs. Figure 1a displays the device structure of PeLEDs with and without NHAs, as well as the molecular structures of transport Organic-inorganic hybrid perovskite light-emitting diodes (PeLEDs) are promising for next-generation optoelectronic devices due to their potential to achieve high color purity, efficiency, and brightness. Although the external quantum efficiency (EQE) of PeLEDs has recently surpassed 20%, various strategies are being pursued to increase EQE further and reduce the EQE gap compared to other LED technologies. A key point to further boost EQE of PeLEDs is linked to the high refractive index of the perovskite emissive layer, leading to optical losses of more than 70% of ...

The electrochromic mechanism of IrO 2 thin films was investigated with electrochemical quartz crystal microbalance and surface analyses such as X-ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy. Prior to pulsed anodic current electrodeposition of IrO 2 thin film on indium-tin oxide substrate ͑total anodic charge 100 mC/cm 2 ͒, IrO 2 islands, which work as good adhesive seeds, were prepared by cyclic voltammetry. In phosphate buffered saline solution, IrO 2 exhibited blue and black anodic electrochromic behavior at two oxidation potentials of ϩ0.5 and ϩ0.9 V ͑vs. a saturated calomel electrode͒. Surface analysis and mass variations of IrO 2 thin film indicated that the ejection of H ϩ and the injection of Na ϩ caused the cracks in the film and resulted in coloring behaviors.Electrochromism is the reversible color change of electrochromic materials by applying a small voltage or current and, thus, it has drawn interest for optical devices such as smart windows, automotive mirrors, and light shutters. In electrochromic devices ͑ECDs͒, the selection of electrochromic materials is an important factor for effective coloration bleaching. Two typical electrochromic materials are metal oxides ͑e.g., IrO 2 , 1,2 WO 3 , 3,4 NiO, 5 and V 2 O 5 6 ͒ and conducting polymers ͑e.g., polypyrrole and polythiophene͒. 7,8 Among electrochromic metal oxides, iridium oxide shows a remarkably fast response to anodic coloration and cathodic bleaching, but its electrochromic characteristics have not been studied intensively compared with other metal oxides.Until now, three possible mechanisms of electrochromic reactions on iridium oxides have been reported ͓injection/ejection of ͑1͒ cation or ͑2͒ anion or ͑3͒ small alkali ions 9 ͔In these electrochromic reactions, mention the injection/ejection of H ϩ has been explained as the most reasonable mechanism on electrochromic iridium oxides.Due to the chemically/mechanically unstable features of iridium oxides, electrochromic properties of IrO 2 thin films are dependent on the preparation conditions and the chemical composition of coating solutions. Five different methods of preparing IrO 2 are as follows: ͑i͒ anodically electrodeposited metal oxide films like PbO 2 ; 1,10 (ii) cathodically electrodeposited metal oxide films ͑e.g., Cu 2 O, ZnO, Y 2 O 3 ); 11-14 (iii) activation of iridium metal by potential cycling to form activated iridium oxide films; 15 (iv) reactive sputtering to form sputtered iridium oxide films; 16 and (v) thermal decomposition of iridium salt solution to form thermal iridium oxide films. 17 In this work, we investigated the electrochromism mechanism of electrodeposited IrO 2 thin films via electrochemical and surface characterization using cyclic voltammetry ͑CV͒, pulsed potential method, in situ electrochemical quartz crystal microbalance ͑EQCM͒ measurement, scanning electron microscope ͑SEM͒, augerelectron spectroscopy ͑AES͒, and X-ray photoelectron spectroscopy ͑XPS͒ analysis. ExperimentalElectrochemical preparation of IrO ...

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Surgical clipping of unruptured intracranial aneurysms in elderly group could get it as a favorable outcome in well selected cases.

The 0.25-mL French straw has been thoroughly studied and compared with the 0.5-mL French straw for about 40 yr. The 0.25-mL straw has some distinct advantages over the 0.5-mL straw in terms of storage efficiency and extender usage. The 0.25-mL straw is more sensitive to temperature change, which may be an advantage in some freezing systems with a slow freezing rate, but provides no advantage when the freezing rate is accelerated to optimize freezing in 0.5-mL straws. Disadvantages of the 0.25-mL straw include increased sensitivity to post-thaw temperature change, slightly more difficult handling, and inferior readability. Fertility of cattle inseminated with extended semen packaged in 0.25-mL straws assessed in 13 studies (>770,000 inseminations) had a weighted advantage of 0.9% (0.7% unweighted advantage) compared with semen packaged in 0.5-mL straws. In 2 studies in which palpated conception rates were obtained, the weighted advantage of the 0.25-mL versus the 0.5-mL straw was 0.2% (0.4% unweighted advantage). Paired t-tests did not detect a significant difference in pregnancy outcome between straw sizes. Logistic regression of all 15 studies (>780,000 inseminations) detected large variation among studies and tended to detect a small advantage for the 0.25-mL straw. Meta-analyses applied to fixed- or random-effect models of all 15 studies indicated the average odds of having a greater pregnancy outcome with the 0.25-mL straw were either 3 or 4% greater. Based on these odds ratios, the expected proportion of difference in pregnancy outcome translated into a difference of 0.74%. These small differences in pregnancy outcomes do not provide compelling evidence that a transition from 0.50- to 0.25-mL straws in the United States is warranted, especially given the added negative aspects of semen handling and the greater potential for technician x straw type interactions among herdsman inseminators.

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Metal halide perovskite light-emitting diodes (PeLEDs) are emerging as a promising candidate for next-generation optoelectronic devices. The efficiency of PeLEDs has developed explosively in a short time, but their overall efficiency is still low. This is strongly related to the high refractive indexes of indium-tin-oxide (ITO) and perovskite emitting layers. Various outcoupling strategies are being introduced to outcouple the light trapped inside the layers. However, the proposed methods have experimental challenges that need to be overcome for application to large-area electronics. Based on optical simulations, we demonstrate that the thicknesses of the ITO and perovskite layers are key parameters to improve the outcoupling efficiency of PeLEDs. In addition, the optical energy losses of PeLEDs can be reduced significantly by properly adjusting the thicknesses of the two layers. This leads to outstanding optical performance with a maximum EQE greater than 20% without using any other external outcoupling strategies.

Rationale:A 76-year-old female patient was diagnosed with an aneurysmal subarachnoid hemorrhage following rupture of a right posterior communicating artery aneurysm.Patient concerns:She was treated surgically with clipping of the aneurysmal neck. Six months after onset, when starting rehabilitation at our hospital, she showed no spontaneous movement or speech.Diagnoses:aneurysmal subarachnoid hemorrhage following rupture of a right posterior communicating artery aneurysm.Interventions:During 2 months’ rehabilitation, her AM did not improve significantly. As there was no apparent change, she underwent a ventriculo-peritoneal shunt operation for hydrocephalus 8 months after her stroke. After the surgery, she remained in the AM state, but participated in a comprehensive rehabilitative management program similar to that before shunt operation. During 1 month's intensive rehabilitation, her AM gradually improved. At 9 months after onset, she became able to perform some daily activities by herself including eating, washing, and dressing. In addition, she could speak with some fluency.Outcomes:On 6-month DTT, the neural connectivity of the caudate nucleus (CN) to the medial prefrontal cortex (PFC, Broadmann area [BA]: 10 and 12) and orbito-frontal cortex (BA 11 and 13) was low in both hemispheres. However, the neural connectivity of the CN to the medial PFC increased on both sides on 9-month DTT. The integrity of the arcuate fasciculus (AF) was preserved in both hemispheres on both 6- and 9-month DTTs.Lessons:Recovery of AM and injured PCTs was observed in a stroke patient.