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Cs2LiLaBr6: Ce (CLLB) scintillator with the size of Φ 21mm × 25 mm coupled with PMT was used to detect neutron and gamma rays. The pulse shape discrimination (PSD) of neutrons and gamma rays by charge comparison method, the neutrons and gamma rays from AmBe source and fast neutron beam can be separated with figure-of-merit (FOM) values of 0.9 and 1.3, respectively. However, some neutron and gamma rays are difficult to distinguish, so new algorithms need to be investigated to improve the PSD performance of neutron and gamma. Artificial neural networks (ANN) have a very good image recognition capability, thus the ANN model was constructed to discriminate the waveforms of neutron and gamma rays. After ANN model training, the neutron and gamma signals of the CLLB detector were recognized with an accuracy of 98%, and the FOM value of the ANN method was calculated to be 19.4. This result is much higher than the charge comparison method, indicating better discrimination between neutrons and gamma rays with the ANN method.

Abstract Changes of membrane lipids in cisplatin-sensitive A549 and cisplatin-resistant A549/DDP cells during the apoptotic process induced by a clinical dose of cisplatin (30 μM) were detected by 1H and 31P-NMR spectroscopy and by membrane fluidity measurement. The apoptotic phenotypes of the two cell lines were monitored with flow cytometry. The assays of apoptosis showed that significant apoptotic characteristics of the A549 cells were induced when the cells were cultured for 24 hours after treatment with cisplatin, while no apoptotic characteristic could be detected for the resistant A549/DDP cells even after 48 hours. The results of 1H-NMR spectroscopy demonstrated that the CH2/CH3 and Glu/Ct ratios of the membrane of A549 cells increased significantly, but those in A549/DDP cell membranes decreased. In addition, the Chol/CH3 and Eth/Ct ratios decreased for the former but increased for the latter cells under the same conditions. 31P-NMR spectroscopy indicated levels of phosphomonoesters (PME) and ATP decreased in A549 but increased in A549/DDP cells after being treated with cisplatin. These results were supported with the data obtained from 1H-NMR measurements. The results clearly indicated that components and properties of membrane phospholipids of the two cell lines were significantly different during the apoptotic process when they were treated with a clinical dose of cisplatin. Plasma membrane fluidity changes during cisplatin treatment as detected with the fluorescence probe TMA-DPH also indicate marked difference between the two cell lines. We provided evidence that there are significant differences in plasma membrane changes during treatment of cisplatin sensitive A549 and resistant A549/DDP cells.

The functional and biological significance of selected CASP13 targets are described by the authors of the structures. The structural biologists discuss the most interesting structural features of the target proteins and assess whether these features were correctly reproduced in the predictions submitted to the CASP13 experiment.

The conserved coat protein complex II (COPII) mediates the initial steps of secretory protein trafficking by assembling onto subdomains of the endoplasmic reticulum (ER) in two layers to generate cargo-laden transport carriers that ultimately fuse with an adjacent ER-Golgi intermediate compartment (ERGIC). Here, we demonstrate that Trk-fused gene (TFG) binds directly to the inner layer of the COPII coat. Specifically, the TFG C terminus interacts with Sec23 through a shared interface with the outer COPII coat and the cargo receptor Tango1/cTAGE5. Our findings indicate that TFG binding to Sec23 outcompetes these other associations in a concentration-dependent manner and ultimately promotes outer coat dissociation. Additionally, we demonstrate that TFG tethers vesicles harboring the inner COPII coat, which contributes to their clustering between the ER and ERGIC in cells. Together, our studies define a mechanism by which COPII transport carriers are retained locally at the ER/ERGIC interface after outer coat disassembly, which is a prerequisite for fusion with ERGIC membranes.

Low‐dimensional copper‐based halide single crystals are considered excellent scintillators for indirect X‐ray detection, but their potential in direct X‐ray detection has not been investigated. Herein, high‐quality pure Cs3Cu2I5 and Li‐doped Cs3Cu2I5:Li single crystals are grown by the Bridgman method. The Li+ dopant enhances the photoelectric properties of the Cs3Cu2I5 single crystal by extending the carrier lifetime, improving the carrier mobility from 6.49 to 9.52 cm2 V−1 s−1, and increasing the mobility‐lifetime (µτ) product from 1.4 × 10−4 to 2.9 × 10−4 cm2 V−1. The sensitive direct X‐ray detector with a vertical device configuration of Au/Cs3Cu2I5:Li single crystal/PCBM/Au is fabricated and demonstrated to have a high sensitivity of 831.1 µC Gyair−1 cm−2 and low detection limit of 34.8 nGyair s−1. Furthermore, the detector shows negligible baseline current drift and excellent stability upon X‐ray radiation. [ABSTRACT FROM AUTHOR]

Halide perovskites are among the most attractive research hotspots in optoelectronic applications due to their excellent luminescence properties. In this paper, Li+ was successfully incorporated into a one-dimensional perovskite CsCu2I3 host and constructed as a novel neutron/gamma detection scintillator via the Bridgman method. XRD and ICP-MS were carried out, and the results were discussed. The Li-doped CsCu2I3 crystal exhibits a main emission peak at 575 nm originating from strongly localized 1D exciton emission and a high photoluminescence quantum efficiency of 18.7%. The CsCu2I3:Li crystal has a light yield of 10 900 photons per MeV and an energy resolution of 11.5% under 137Cs irradiation. The figure-of-merit (FoM) of the CsCu2I3:Li crystal has been estimated (about 0.8) under 252Cf radiation source. The crystal has a potential application for dual gamma–neutron detection. [ABSTRACT FROM AUTHOR]

Recently, the all-inorganic metal halide Cs3Cu2I5 has attracted extensive attention because of its potential use in X-ray and gamma ray detection. Herein, a high-quality and efficient Li+-doped Cs3Cu2I5 single crystal with good air stability was grown and utilized for dual gamma ray and neutron detection for the first time. X-ray diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma optical emission spectrometry, and nuclear magnetic resonance were employed to prove that Li+ was successfully introduced into Cs3Cu2I5, and the lattice sites of Li+ were investigated. The photoluminescence quantum efficiency of the Cs3Cu2I5 crystal was improved from 83.4% to 88.6% via Li+ doping. The photoluminescence and X-ray results showed that the emission peak of Cs3Cu2I5:Li was located at 445 nm and was ascribed to the self-trapped exciton emission. The light yield and energy resolution of the Cs3Cu2I5 crystal were significantly improved under 137Cs irradiation after Li+ doping. The effects of the Li+ doping on the performance were also investigated. In particular, the Cs3Cu2I5:Li crystal achieved an excellent figure-of-merit of 2.25, which showed its significant potential for dual gamma-ray and neutron detection applications. [ABSTRACT FROM AUTHOR]

Phosphatidylinositol 3,4,5-triphosphate (PIP3) plays a key role in neuronal polarization and axon formation. PIP3-containing vesicles are transported to axon tips by the kinesin KIF13B via an adaptor protein, centaurin [alpha]1 (CENTA1). KIF13B interacts with CENTA1 through its forkhead-associated (FHA) domain. We solved the crystal structures of CENTA1 in ligand-free, KIF13B-FHA domain-bound, and PIP3 head group (IP4)-bound conformations, and the CENTA1/ KIF13B-FHA/IP4 ternary complex. The first pleckstrin homology (PH) domain of CENTA1 specifically binds to PIP3, while the second binds to both PIP3 and phosphatidylinositol 3,4-biphosphate (PI(3,4)[P.sub.2]). The FHA domain of KIF13B interacts with the PH1 domain of one CENTA1 molecule and the ArfGAP domain of a second CENTA1 molecule in a threonine phosphorylation-independent fashion. We propose that full-length KIF13B and CENTA1 form heterotetramers that can bind four phosphoinositide molecules in the vesicle and transport it along the microtubule. kinesin | forkhead-associated domain | vesicle transport | phosphatidylinositol triphosphate | neuronal development doi/ 10.1073/pnas.1009008107