Organic near‐infrared (NIR) luminogens have attracted intensive attention considering their vast potential applications in areas like bioimaging, organic light‐emitting diodes (OLEDs) and ...night‐vision telecommunication. However, organic NIR luminogens with high solid quantum efficiencies are scarce, limiting their applications. Here, we reported an electron‐deficient acceptor, BSM, based on dithiafulvalene and benzothiadiazole, which could work as a strong acceptor to produce highly efficient NIR emitters with aggregation‐induced emission (AIE) property. One of the AIEgens, TBSMCN emitted at 820 nm with a solid quantum yield of 10.7 %. When applied to solution‐processed OLEDs, an outstanding external quantum efficiency (EQE) of 9.4 % was achieved with a peak wavelength at 728 nm. Moreover, its non‐doped device could achieve an extraordinary EQE of 2.2 % peaking at 804 nm. In the further optimized configuration, when an extra sensitizer was added to harvest triplet excitons, the EQE unprecedentedly soared up to 14.3 % with a peak wavelength of 750 nm.
A new acceptor core, obtained by fusing dithiafulvalene with benzothiadiazole, was utilized to construct near‐infrared AIEgen luminophores, in which TBSMCN emitted at 820 nm in the solid state and featured a high quantum yield of 10.7 %. The doped and non‐doped NIR OLEDs achieved excellent external quantum efficiencies of 14.3 % and 2.2 % peaking at 750 and 804 nm, respectively.
We present the improved constraints on couplings of solar axions and more generic bosonic dark matter particles using 737.1 kg days of data from the CDEX-1B experiment. The CDEX-1B experiment, ...located at the China Jinping Underground Laboratory, primarily aims at the direct detection of weakly interacting massive particles using a p-type point-contact germanium detector. We adopt the profile likelihood ratio method for analysis of data in the presence of backgrounds. An energy threshold of 160 eV was achieved, much better than the 475 eV of CDEX-1A with an exposure of 335.6 kg days. This significantly improves the sensitivity for the bosonic dark matter below 0.8 keV among germanium detectors. Limits are also placed on the coupling gAe < 2.48 × 10−11 from Compton, bremsstrahlung, atomic-recombination, and deexcitation channels and geffAN × gAe < 4.14 × 10−17 from a 57Fe M1 transition at 90% confidence level.
The CDEX-1 experiment conducted a search of low-mass (< 10GeV/c super(2)) weakly interacting massive particles dark matter at the China Jinping Underground Laboratory using a p-type point-contact ...germanium detector with a fiducial mass of 915 g at a physics analysis threshold of 475 eVee. We report the hardware setup, detector characterization, data acquisition, and analysis procedures of this experiment. No excess of unidentified events is observed after the subtraction of the known background. Using 335.6 kg-days of data, exclusion constraints on the weakly interacting massive particle-nucleon spin-independent and spin-dependent couplings are derived.
Multiple death signals influence mitochondria during apoptosis, yet the critical initiating event for mitochondrial dysfunction in vivo has been unclear. tBID, the caspase-activated form of a ..."BH3-domain-only" BCL-2 family member, triggers the homooligomerization of "multidomain" conserved proapoptotic family members BAK or BAX, resulting in the release of cytochrome c from mitochondria. We find that cells lacking both Bax and Bak, but not cells lacking only one of these components, are completely resistant to tBID-induced cytochrome c release and apoptosis. Moreover, doubly deficient cells are resistant to multiple apoptotic stimuli that act through disruption of mitochondrial function: staurosporine, ultraviolet radiation, growth factor deprivation, etoposide, and the endoplasmic reticulum stress stimuli thapsigargin and tunicamycin. Thus, activation of a "multidomain" proapoptotic member, BAX or BAK, appears to be an essential gateway to mitochondrial dysfunction required for cell death in response to diverse stimuli.
Somatic mutations of mitochondrial DNA (mtDNA) have been extensively identified mainly by traditional Sanger sequencing technology in various cancer types. However, low detection sensitivity of ...traditional methods greatly limits the comprehensive profiling of mtDNA somatic mutations in cancers, especially in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Moreover, the functional roles of mtDNA mutation in HBV-related hepatocarcinogenesis have not been systematically revealed.
Next-generation sequencing (NGS) platform was applied to profile the somatic mtDNA mutations of HCC and paired paratumor (non-HCC) tissues from a large cohort of 156 HBV-HCC patients.
Our data revealed the common existence of mtDNA mutation in both inflammatory and cancer tissues with significantly different mutation pattern. The mutation density (mutation number/region length) of D-loop region was much higher than that of other regions in both HCC and non-HCC tissues. Unexpectedly, the average mutation number in D-loop region of HCC tissues was significantly less than that of non-HCC tissues. In contrast, the heteroplasmy level of D-loop region mutations was significantly increased in HCC tissues, implying that the D-loop mutations might be positively selected in HCC tissues. Furthermore, our results indicated that the patients with D-loop mutations had a significantly lower mtDNA copy number and were more likely to relapse. In vitro experiments demonstrated that proliferation, invasion and metastasis ability of HCC cells with D-loop region mutations were significantly higher than those without D-loop region mutations.
These results emphasize the critical contributing role of somatic mtDNA D-loop mutations in HBV-related hepatocarcinogenesis.
This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at ...Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.
A colorimetric and surface-enhanced Raman scattering (SERS) signal amplification platform based on 2-step aggregation of gold nanoparticles (AuNP) was constructed for the sensitive detection of ...melamine. In this study, the positively charged SYBR Green I was used for the first step of aggregation of AuNP, via charge neutralization, to obtain small-sized AuNP aggregates. The positively charged SYBR Green I decreased the negative charges of the surface of AuNP, which was beneficial to the aggregation of AuNP. In addition, the melamine could aggregate AuNP by decreasing the negative charges of the surface of AuNP and self-assemble with each other on the surface of AuNP by hydrogen bonds. Therefore, the second efficient aggregation of small-sized AuNP aggregates could be achieved with melamine at low concentration, resulting in significant signal changes of color and SERS. The sensitivity of a colorimetric (0.60 mg/L) and SERS (0.089 mg/L) platform, based on 2-step aggregation of AuNP, was 15 and 2.2 times higher than that based on 1-step aggregation of AuNP for detecting melamine.