Fluorescent molecular rotors (FMRs) can act as viscosity sensors in various media including subcellular organelles and microfluidic channels. In FMRs, the rotation of rotators connected to a ...fluorescent π‐conjugated bridge is suppressed by increasing environmental viscosity, resulting in increasing fluorescence (FL) intensity. In this minireview, we describe recently developed FMRs including push–pull type π‐conjugated chromophores, meso‐phenyl (borondipyrromethene) (BODIPY) derivatives, dioxaborine derivatives, cyanine derivatives, and porphyrin derivatives whose FL mechanism is viscosity‐responsive. In addition, FMR design strategies for addressing various issues (e.g., obtaining high FL contrast, internal FL references, and FL intensity‐contrast trade‐off) and their biological and microfluidic applications are also discussed.
Spinning around: This minireview discusses recently developed fluorescent molecular rotors (FMRs), which act as viscosity sensors in various media including subcellular organelles and microfluidic channels. In addition, the mechanism of viscosity‐responsive fluorescence, design strategy of FMRs for addressing remarkable issues, and their various biological and microfluidic applications, are also discussed.
Metal halide perovskites are attracting a lot of attention as next-generation light-emitting materials owing to their excellent emission properties, with narrow band emission
. However, perovskite ...light-emitting diodes (PeLEDs), irrespective of their material type (polycrystals or nanocrystals), have not realized high luminance, high efficiency and long lifetime simultaneously, as they are influenced by intrinsic limitations related to the trade-off of properties between charge transport and confinement in each type of perovskite material
. Here, we report an ultra-bright, efficient and stable PeLED made of core/shell perovskite nanocrystals with a size of approximately 10 nm, obtained using a simple in situ reaction of benzylphosphonic acid (BPA) additive with three-dimensional (3D) polycrystalline perovskite films, without separate synthesis processes. During the reaction, large 3D crystals are split into nanocrystals and the BPA surrounds the nanocrystals, achieving strong carrier confinement. The BPA shell passivates the undercoordinated lead atoms by forming covalent bonds, and thereby greatly reduces the trap density while maintaining good charge-transport properties for the 3D perovskites. We demonstrate simultaneously efficient, bright and stable PeLEDs that have a maximum brightness of approximately 470,000 cd m
, maximum external quantum efficiency of 28.9% (average = 25.2 ± 1.6% over 40 devices), maximum current efficiency of 151 cd A
and half-lifetime of 520 h at 1,000 cd m
(estimated half-lifetime >30,000 h at 100 cd m
). Our work sheds light on the possibility that PeLEDs can be commercialized in the future display industry.
This study reports a new nonfullerene electron transporting material (ETM) based on naphthalene diimide (NDI) small molecules for use in high‐performance perovskite solar cells (PSCs). These solar ...cells simultaneously achieve high power conversion efficiency (PCE) of over 20% and long‐term stability. New NDI‐ID (N,N′‐Bis(1‐indanyl)naphthalene‐1,4,5,8‐tetracarboxylic diimide) consisting of an N‐substituted indane group having simultaneous alicyclic and aromatic characteristics is synthesized by a low‐cost, one‐step reaction, and facile purification method. The partially flexible characteristics of an alicyclic cyclopentene group on indane groups open the possibility of low‐temperature solution processing. The conformational rigidity and aromaticity of phenyl and alicyclic groups contribute to high temporal stability by strong secondary bonds. NDI‐ID has herringbone packed semiconducting NDI cores that exhibit up to 0.2 cm2 V−1 s−1 electron mobility in field effect transistors. The inverted PSCs based on CH(NH2)2PbI3–xBrx with NDI‐ID ETM exhibit very high PCEs of up to 20.2%, which is better than that of widely used PCBM (phenyl‐C61‐butyric acid methyl ester) ETM‐based PSCs. Moreover, NDI‐ID‐based PSCs exhibit very high long‐term temporal stability, retaining 90% of the initial PCE after 500 h at 100 °C with 1 sun illumination without encapsulation. Therefore, NDI‐ID is a promising ETM for highly efficient, stable PSCs.
A new nonfullerene electron transporting material based on naphthalene diimide with indane groups having simultaneous alicyclic and aromatic characteristics is developed for low‐temperature solution‐processable perovskite solar cells, and it shows up to 20.2% power conversion efficiency and long‐term temporal stability.
A new type of cellular material named Shellular, in which cells are composed of a continuous, smooth‐curved shell according to the minimal surface theory, is proposed. Shellular specimens are ...fabricated using 3D lithography with negative templates and hard coating, and exhibit superb strength and stiffness at densities lower than 10−2 Mg m−3, incorporating benefits from hierarchical structures and constituent materials with nanosized grains.
This study presents newly developed yellow‐colored organic electro‐optic crystals to provide high terahertz (THz) wave generation efficiency. Compared with currently existing red‐ or orange‐colored ...electro‐optic crystals, which are used for most benchmark organic THz sources, yellow‐colored crystals have additional superior advantages for THz wave generation, e.g., higher transparency in the visible wavelength range with accompanying different phase‐matching possibilities. The new yellow‐colored crystals consist of a highly nonlinear optical 4‐(4‐hydroxystyryl)‐1‐methylpyridinium (OHP) cation, with a relatively short wavelength of maximal absorption at 390 nm in solution, and various halogen‐substituted benzenesulfonate anions, with strong secondary‐bonding ability. OHP 4‐chlorobenzenesulfonate (OHP‐CBS) crystals exhibit large off‐resonant macroscopic optical nonlinearity and high transparency, with a cut‐off wavelength for solid‐state absorption near 490 nm. OHP‐CBS crystals provide excellent THz wave generation characteristics based on optical rectification. A 0.53 mm thick OHP‐CBS crystal delivers ≈27 times higher optical‐to‐THz conversion efficiency and a much broader spectrum bandwidth compared with the standard 1.0 mm thick ZnTe at 1300 nm pumping. Particularly, compared with a benchmark organic quinolinium crystal with a similar thickness of 0.55 mm, OHP‐CBS crystals exhibit 1.7 times higher optical‐to‐THz conversion efficiency, and show a significantly different THz spectral shape.
Yellow‐colored electro‐optic salt crystals possessing large macroscopic optical nonlinearity with wide transparency exhibit excellent THz wave generation characteristics with significantly different THz spectral shapes compared with red‐ or orange‐colored benchmark organic electro‐optic crystals.
Atopic dermatitis (AD) is a heterogeneous disease that manifests with a wide variety of clinical symptoms and signs. Due to the lack of definitive biomarkers for AD, it is very difficult to set up ...standard diagnostic criteria for AD which cover the entire spectrum of AD patients. Various instruments have been proposed for AD diagnosis, and they can be classified into a hospital setting or a community setting. From the preventive medicine viewpoint, questionnaire‐based diagnostic criteria in a community setting are important to detect and manage childhood AD patients properly. In this article, various diagnostic criteria for AD in hospital and community settings will be reviewed. Additionally, the Reliable Estimation of Atopic Dermatitis in Childhood (REACH), a new full questionnaire‐based diagnostic tool for childhood AD, will be reviewed.
Switching to the atomic scaleFerroelectric materials are attractive because they provide a way to change electrical resistance by using an electric field. Lee et al. used simulations to explain the ...persistence of ferroelectric behavior in very thin films of hafnium oxide (see the Perspective by Noheda and Íñiguez). The authors' calculations show that ferroelectric properties should be found in films below 1 nanometer thick. This makes the material very attractive for the next generation of random access memory.Science, this issue p. 1343; see also p. 1300Discovery of robust yet reversibly switchable electric dipoles at reduced dimensions is critical to the advancement of nanoelectronics devices. Energy bands flat in momentum space generate robust localized states that are activated independently of each other. We determined that flat bands exist and induce robust yet independently switchable dipoles that exhibit a distinct ferroelectricity in hafnium dioxide (HfO2). Flat polar phonon bands in HfO2 cause extreme localization of electric dipoles within its irreducible half-unit cell widths (~3 angstroms). Contrary to conventional ferroelectrics with spread dipoles, those intrinsically localized dipoles are stable against extrinsic effects such as domain walls, surface exposure, and even miniaturization down to the angstrom scale. Moreover, the subnanometer-scale dipoles are individually switchable without creating any domain-wall energy cost. This offers unexpected opportunities for ultimately dense unit cell–by–unit cell ferroelectric switching devices that are directly integrable into silicon technology.
Highly efficient nonlinear optical organic crystals are very attractive for various photonic applications including terahertz (THz) wave generation. Up to now, only two classes of ionic crystals ...based on either pyridinium or quinolinium with extremely large macroscopic optical nonlinearity have been developed. This study reports on a new class of organic nonlinear optical crystals introducing electron‐accepting benzothiazolium, which exhibit higher electron‐withdrawing strength than pyridinium and quinolinium in benchmark crystals. The benzothiazolium crystals consisting of new acentric core HMB (2‐(4‐hydroxy‐3‐methoxystyryl)‐3‐methylbenzodthiazol‐3‐ium) exhibit extremely large macroscopic optical nonlinearity with optimal molecular ordering for maximizing the diagonal second‐order nonlinearity. HMB‐based single crystals prepared by simple cleaving method satisfy all required crystal characteristics for intense THz wave generation such as large crystal size with parallel surfaces, moderate thickness and high optical quality with large optical transparency range (580–1620 nm). Optical rectification of 35 fs pulses at the technologically very important wavelength of 800 nm in 0.26 mm thick HMB crystal leads to one order of magnitude higher THz wave generation efficiency with remarkably broader bandwidth compared to standard inorganic 0.5 mm thick ZnTe crystal. Therefore, newly developed HMB crystals introducing benzothiazolium with extremely large macroscopic optical nonlinearity are very promising materials for intense broadband THz wave generation and other nonlinear optical applications.
A new class of nonlinear optical crystals introducing benzothiazolium exhibit large macroscopic optical nonlinearity with optimal molecular ordering and suitable crystal characteristics for intense terahertz (THz) wave generation. This results in one order of magnitude higher THz wave generation efficiency with considerably broader bandwidth than inorganic standard ZnTe crystal when pumped at the technologically important wavelength of 800 nm.
Abstract
Calcium flux regulating intracellular calcium levels is essential and modulated for efficient efferocytosis. However, the molecular mechanism by which calcium flux is modulated during ...efferocytosis remains elusive. Here, we report that Orai1, a Crbn substrate, is upregulated via its attenuated interaction with Crbn during efferocytosis, which increases calcium influx into phagocytes and thereby promotes efferocytosis. We found that Crbn deficiency promoted phagocytosis of apoptotic cells, which resulted from facilitated phagocytic cup closure and was nullified by a CRAC channel inhibitor. In addition, Orai1 associated with Crbn, resulting in ubiquitination and proteasomal degradation of Orai1 and alteration of SOCE-mediated calcium influx. The association of Orai1 with Crbn was attenuated during efferocytosis, leading to reduced ubiquitination of Orai1 and consequently upregulation of Orai1 and calcium influx. Collectively, our study reveals a regulatory mechanism by which calcium influx is modulated by a Crbn-Orai1 axis to facilitate efferocytosis.
Abstract Background Context Little is known about the effect of rod stiffness as a risk factor for proximal junctional kyphosis (PJK) after adult spinal deformity (ASD) surgery. Purpose The aim of ...this study was to compare radiographical outcomes after the use of cobalt chrome multiple-rod constructs (CoCr MRC) and titanium alloy two-rod constructs (Ti TRC) for the ASD) surgery with minimum 1-year follow-up. Study Design Retrospective case-control study in two institutes. Patients Sample We included 54 patients who underwent ASD surgery with fusion to sacrum in two academic institutes between 2002 and 2015. Outcome Measures Radiographical outcomes were measured on the standing lateral radiographs before surgery, 1 month postoperatively and at ultimate follow-up. They were composed of pre-and postoperative sagittal vertical axis (SVA), pre-and postoperative lumbar lordosis (LL), pre-and postoperative thoracic kyphosis (TK)+ LL+ pelvic incidence (PI), pre-and postoperative PI minus LL, level of upper instrumented level (UIV), evaluation of fusion after surgery, the presence of proximal junctional kyphosis (PJK), and the occurrence of rod fracture. Methods We reviewed the medical records of 54 patients who underwent ASD surgery. Of these, 20 patients had CoCr MRC and 34 patients had Ti TRC. Baseline data and radiographical measurements were compared between two groups. . The Mann-Whitney U test, the chi square test, and the Fisher exact test were used to compare outcomes between groups. Results Patients of the groups were similar in terms of age, gender, diagnosis, number of three column osteotomy, levels fused, bone mineral density, preoperative TK, pre-and postoperative TK+LL+PI, SVA difference, LL change, pre-and postoperative PI minus LL and the location of UIV (upper-or lower thoracic). However, there were significant differences in the occurrence of PJK and rod breakage (PJK : CoCr MRC: 12 (60%) vs Ti TRC: 9 (26.5%), P =0.015; the occurrence of rod breakage : CoCr MRC: 0 (0%) vs Ti TRC: 11 (32.4%), P =0.004). The time of PJK was less than 12 months after surgery in CoCr MRC group. However, 55.5% (5/9) of PJK developed over 12 months after surgery in Ti TRC group. Conclusions Increasing the rod stiffness by use of CoCr and MRC can prevent rod breakage, however, adversely affects the occurrence and the time of PJK.
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