Simultaneous enhancement of out-coupling efficiency, internal quantum efficiency, and color purity in thermally activated delayed fluorescence (TADF) emitters is highly desired for the practical ...application of these materials. We designed and synthesized two isomeric TADF emitters, 2DPyM-mDTC and 3DPyM-pDTC, based on di(pyridinyl)methanone (DPyM) cores as the new electron-accepting units and di(tert-butyl)carbazole (DTC) as the electron-donating units. 3DPyM-pDTC, which is structurally nearly planar with a very small ΔE ST, shows higher color purity, horizontal ratio, and quantum yield than 2DPyM-mDTC, which has a more flexible structure. An electroluminescence device based on 3DPyM-pDTC as the dopant emitter can reach an extremely high external quantum efficiency of 31.9% with a pure blue emission. This work also demonstrates a way to design materials with a high portion of horizontal molecular orientation to realize a highly efficient pure-blue device based on TADF emitters.
An ideal material has yet to be discovered that can completely treat dentin hypersensitivity; however, calcium phosphate precipitation has exhibited potential value for the treatment of dentin ...hypersensitivity by the occlusion of dentinal tubules. We hypothesized that a novel mesoporous silica biomaterial (nano CaO@mesoporous silica, NCMS) containing nano-sized calcium oxide particles mixed with 30% phosphoric acid can efficiently occlude dentinal tubules and significantly reduce dentin permeability, even with the presence of pulpal pressure. This highly supersaturated Ca2+-and HPO4
2−ion-containing NCMS paste was brushed onto dentin surfaces, and the ions diffused deeply into the dentinal tubules and formed a CaHPO4·2H2O precipitation with a depth of 100 μm. The results of the dentin permeability tests showed that the novel mesoporous material exhibited a significant reduction in dentin permeability (p < 0.05), even under simulated pulpal pressure, as compared with our previously developed material, DP-bioglass, and a commercial desensitizing material, Seal & Protect®.
Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes
. Their physical origin remains unknown, but dozens of possible models have been postulated
. Some FRB sources exhibit repeat ...bursts
. Although over a hundred FRB sources have been discovered
, only four have been localized and associated with a host galaxy
, and just one of these four is known to emit repeating FRBs
. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source
, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure
further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.
We report on the discovery of eight repeating fast radio burst (FRB) sources found using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. These sources span a dispersion measure ...(DM) range of 103.5-1281 pc cm−3. They display varying degrees of activity: six sources were detected twice, another three times, and one 10 times. These eight repeating FRBs likely represent the bright and/or high-rate end of a distribution of infrequently repeating sources. For all sources, we determine sky coordinates with uncertainties of ∼10′. FRB 180916.J0158+65 has a burst-averaged DM = 349.2 0.3 pc cm−3 and a low DM excess over the modeled Galactic maximum (as low as ∼20 pc cm−3); this source also has a Faraday rotation measure (RM) of −114.6 0.6 rad m−2, which is much lower than the RM measured for FRB 121102. FRB 181030.J1054+73 has the lowest DM for a repeater, 103.5 0.3 pc cm−3, with a DM excess of ∼70 pc cm−3. Both sources are interesting targets for multi-wavelength follow-up due to their apparent proximity. The DM distribution of our repeater sample is statistically indistinguishable from that of the first 12 CHIME/FRB sources that have not yet repeated. We find, with 4 significance, that repeater bursts are generally wider than those of CHIME/FRB bursts that have not repeated, suggesting different emission mechanisms. Many of our repeater events show complex morphologies that are reminiscent of the first two discovered repeating FRBs. The repetitive behavior of these sources will enable interferometric localizations and subsequent host galaxy identifications.
Objective
PANSS‐8 and PANSS‐6 are derived from the 30‐item Positive and Negative Syndrome Scale (PANSS‐30). We investigate whether PANSS‐8 or PANSS‐6 is a reliable, valid, sensitive to change ...measure, and scalable, and whether early improvement using them can predict response/remission.
Method
Data were from 3 trials for 270 schizophrenia inpatients receiving antipsychotics. Internal consistency, validity, sensitivity to change, and scalability using PANSS‐30, PANSS‐8, and PANSS‐6 at each assessment were examined. Early improvement was defined as at least 20% reduction of PANSS‐30, PANSS‐8, or PANSS‐6 scores at week 2. Response was defined as at least 40% reduction of PANSS‐30 and remission as a score of PANSS‐8 ≤ 3 on each item at endpoint. Receiver operating characteristic analysis was used to determine which rating scale had better discriminative capacity.
Results
PANSS‐8 and PANSS‐6 showed acceptable internal consistency, were highly correlated with PANSS‐30, and had sensitivity to change. PANSS‐8 and PANSS‐6 were scalable at each assessment, except for PANSS‐6 at baseline. Early improvement using PANSS‐8 or PANSS‐6 had comparable predictive values with that of PANSS‐30 for response/remission.
Conclusion
PANSS‐8 and PANSS‐6 are clinically useful measures. Early improvement, regardless of whether PANSS‐30, PANSS‐8, or PANSS‐6 is used, is a statistically significant predictor of response/remission.
The 3D printed bulk samples fabricated by selective laser melting (SLM) of the additive manufacturing technique are usually considered to be 3D isotropic in microstructures and mechanical responses. ...This study systematically investigates the anisotropic responses in terms of hardness and electrochemical resistance for the X-, Y- and Z-planes of the SLM Ti-6Al-4V bulk samples fabricated with the zigzag laser path strategy. Results show that all SLM planes exhibit no significant difference in Young's modulus compared to the mechanically rolled plate. However, the X-plane, referred to the cross-sectional plane perpendicular to the laser moving direction, is found ~20% lower hardness and the lowest corrosion resistance compared to the Y- and Z-planes. The underlying reasoning is researched and discussed. The microstructure observations indicate that artifact holes are induced in the X-plane due to un-uniform laser intensity distribution between two neighboring printing lines. Alternatively, the Y- and Z-planes exhibit dense morphology due to multiple heating while zigzag scanning. Experimental results also indicate that the SLM materials exhibit higher corrosion resistance than the commercial rolled materials.
The nuclear pore complex (NPC) serves as the sole bidirectional gateway of macromolecules in and out of the nucleus. Owing to its size and complexity (∼1,000 protein subunits, ∼110 MDa in humans), ...the NPC has remained one of the foremost challenges for structure determination. Structural studies have now provided atomic-resolution crystal structures of most nucleoporins. The acquisition of these structures, combined with biochemical reconstitution experiments, cross-linking mass spectrometry, and cryo-electron tomography, has facilitated the determination of the near-atomic overall architecture of the symmetric core of the human, fungal, and algal NPCs. Here, we discuss the insights gained from these new advances and outstanding issues regarding NPC structure and function. The powerful combination of bottom-up and top-down approaches toward determining the structure of the NPC offers a paradigm for uncovering the architectures of other complex biological machines to near-atomic resolution.
Four 2-(styryl)triphenylene derivatives (TSs) were synthesized for deep-blue dopant materials. By using a pyrene-containing compound, DMPPP, as the host, the TS-doped devices exhibited significant ...delayed fluorescence via triplet-triplet annihilation, providing the highest quantum efficiency of 10.2% and a current efficiency of 12.3 cd A(-1).
We report the detection of a single burst from the first-discovered repeating fast radio burst (FRB) source, FRB 121102, with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope, ...which operates in the frequency band 400-800 MHz. The detected burst occurred on 2018 November 19 and its emission extends down to at least 600 MHz, the lowest frequency detection of this source yet. The burst, detected with a significance of 23.7 , has fluence 12 3 Jy ms and shows complex time and frequency morphology. The 34 ms width of the burst is the largest seen for this object at any frequency. We find evidence of subburst structure that drifts downward in frequency at a rate of −3.9 0.2 MHz ms−1. Our best fit tentatively suggests a dispersion measure of 563.6 0.5 pc cm−3, which is 1% higher than previously measured values. We set an upper limit on the scattering time at 500 MHz of 9.6 ms, which is consistent with expectations from the extrapolation from higher-frequency data. We have exposure to the position of FRB 121102 for a total of 11.3 hr within the FWHM of the synthesized beams at 600 MHz from 2018 July 25 to 2019 February 25. We estimate on the basis of this single event an average burst rate for FRB 121102 of 0.1-10 per day in the 400-800 MHz band for a median fluence threshold of 7 Jy ms in the stated time interval.
Metabolic syndrome (MS) was conceptualized to identify people at risk for cardiovascular disease and type 2 diabetes; however, the epidemiology of MS and its combinations of components in older ...adults remains unclear. Data from the Senior Health Examination Program of the New Taipei City Government in Taiwan in 2014 were obtained for this study. All participants aged 65 years or older and those with a prior history of cardiovascular disease, cerebrovascular disease, or diabetes mellitus were excluded. 29,164 senior citizens were retrieved for this study, and 12,331 (41.28%) of the participants were male. Female participants were more likely to have MS (42.7% vs.31.3%, p <0.001). Female participants with MS were older than those without MS (73.15±6.5 vs. 72.10±6.14 years, p <0.001). Conversely, male participants with MS were younger than those without MS (72.93±6.70 vs. 73.52±6.98 years, p <0.001). The most common combination of MS components was the triad of high blood glucose, high blood pressure and central obesity (25.2% of all participants with MS). Age-related changes in MS component combinations were noted only when central obesity was present. The strongest MS component combination for new-onset diabetes mellitus was high blood glucose, hypertriglyceridemia, reduced HDL-C and central obesity (HR: 5.42, P<0.001). In conclusion, not all component combinations of MS were of the same prognostic impact or the risk for new-onset diabetes mellitus. Further study is needed to develop individualized intervention programs for MS based on risk profiles of older adults is needed.