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Low-grade gliomas are one of the most common brain tumors in children, where they frequently form within the optic pathway (optic pathway gliomas; OPGs). Since many OPGs occur in the context of the Neurofibromatosis Type 1 (NF1) cancer predisposition syndrome, we have previously employed Nf1 genetically-engineered mouse (GEM) strains to study the pathogenesis of these low-grade glial neoplasms. In the light of the finding that human and mouse low-grade gliomas are composed of Olig2+ cells and that Olig2+ oligodendrocyte precursor cells (OPCs) give rise to murine high-grade gliomas, we sought to determine whether Olig2+ OPCs could be tumor-initiating cells for Nf1 optic glioma. Similar to the GFAP-Cre transgenic strain previously employed to generate Nf1 optic gliomas, Olig2+ cells also give rise to astrocytes in the murine optic nerve in vivo. However, in contrast to the GFAP-Cre strain where somatic Nf1 inactivation in embryonic neural progenitor/stem cells (Nf1flox/mut; GFAP-Cre mice) results in optic gliomas by 3 months of age in vivo, mice with Nf1 gene inactivation in Olig2+ OPCs (Nf1flox/mut; Olig2-Cre mice) do not form optic gliomas until 6 months of age. These distinct patterns of glioma latency do not reflect differences in the timing or brain location of somatic Nf1 loss. Instead, they most likely reflect the cell of origin, as somatic Nf1 loss in CD133+ neural progenitor/stem cells during late embryogenesis results in optic gliomas at 3 months of age. Collectively, these data demonstrate that the cell of origin dictates the time to tumorigenesis in murine optic glioma.

New 2D materials with low‐symmetry structures aroused great interest in developing monolithic polarization‐sensitive photodetectors with small volumes, which can provide a new degree of freedom for more information in night, fog, and smoke environments. However, at least half of them presented a small anisotropy with an anisotropic factor (≈2) of photocurrent up to now. Herein, after systematic investigation of the optical anisotropies of GeSe nanosheets, a novel self‐driven polarization‐sensitive imaging photodetector with excellent performance based on a Top‐MoSe2/GeSe/Bottom‐MoSe2 (T‐MoSe2/GeSe/B‐MoSe2) van der Waals dual‐heterojunction is proposed. Benefitting from the effective separation and shortening transmission distance of photocarriers by fully depleted Van der Waals dual‐heterojunction on both sides of in‐plane anisotropy of GeSe, the anisotropic photocurrent ratio (Imax/Imin) of T‐MoSe2/GeSe/B‐MoSe2 photodetector can reach as high as 12.5 (635 nm, 0 V). This value is 3.5‐fold higher than that of MoSe2/GeSe photodetector, and 7‐fold higher than that of the pristine GeSe photodetector in this work. The responsivity of the T‐MoSe2/GeSe/B‐MoSe2 photodetector (206 mA W−1, 0 V) is 5 times higher than that of the MoSe2/GeSe photodetector. In addition, the T‐MoSe2/GeSe/B‐MoSe2 photodetector exhibited a high light on/off ratio of 4 × 104 at 0 V. This work provides novel insights for developing high‐performance polarization‐sensitive imaging photodetectors. [ABSTRACT FROM AUTHOR]

Reducing power consumption has always been a pressing issue for integrated circuits. Currently, there is a strong interest in the development of self‐powered photodetectors with low power consumption, high quantum efficiency, and high integration. In this work, a novel GaInP/AlGaAs photodetector is developed, where the photovoltaic effect of the Schottky junction is enhanced by the assistance of underneath GaInP/AlGaAs heterojunction, achieving near unity quantum efficiency, high integration, and ultrafast response speed. A single device exhibits a responsivity (R) of 467 mA W−1 in photovoltaic mode, a specific detectivity (D*) of 1.43 × 1011 Jones, a power conversion efficiency (PCE) of 14.5%, and an external quantum efficiency (EQE) of 96.56%. Further, an interconnect integration technique is used to integrate 81 individual detector units onto a 5 × 5 mm2 chip, resulting in a detector array that significantly improves the optical response. The device array has a high frequency feature with a fast response of 19 µs and a −3 dB bandwidth of 21.34 kHz. The interconnect chip is further integrated with a STM32 chip to realize an automotive speed measurement system. This work provides a novel technological solution for a high‐frequency, highly integrated photodetector array using heterojunction‐assisted enhanced GaInP Schottky junctions. [ABSTRACT FROM AUTHOR]

Electrode active materials are the foremost component for energy related electrocatalysis and storage. Rational design and controlled synthesis of hybrid nanostructures is essential to achieve high efficiency but still challenging. Herein, we reported the synthesis of CoS2 nanoparticles embedded in the hollow polyhedron of N‐doped carbon nanotubes (CoS2‐NCNHP), which shows improved electrocatalytic performance for hydrogen evolution reaction (HER) due to the strong synergy effect and the peculiar hollow polyhedral structure. It only needs 158 and 192 mV vs. RHE to arrive the current density to 10 mA cm−2 in 0.5 M H2SO4 and 1 M KOH, and the activity can be kept for at least of 24 h with negligible loss. Density Functional Theory (DFT) calculations suggest more electrons with quickly round‐trip transferred rate in CoS2‐NCNHP can undergo the HER process, CoS2‐NCNHP surface shows optimal interaction with H*, and greatly accelerates the dissociation of H2O molecules. Moreover, CoS2‐NCNHP worked as cathode sulfur host material for aluminum‐sulfur (Al−S) batteries, it exhibits a remarkable increase in the discharge specific capacity, the specific discharge capacity of the battery in the first circle is 515.46 mAh g−1 at 1 A g−1, and the specific discharge capacity can still be maintained at 110 mAh g−1 after 100 cycles, along with a notable reduction in battery polarization owning to the hollow structure enhanced sulfur utilization. [ABSTRACT FROM AUTHOR]

This study comprehensively analyzes type I X-ray bursts observed by Swift/BAT from 2005 to April 2024 to search for X-ray burst oscillations (XBOs) in neutron star low-mass X-ray binaries. XBOs, periodic signals detected within type I X-ray bursts, typically range from 11 to 620 Hz and are often observed in the soft X-ray data of these bursts. Using the high-sensitivity and precise timing capabilities of the Swift/BAT, we found 50 type I X-ray bursts from 37 neutron star low-mass X-ray binaries. We conducted a detailed timing analysis of these bursts. For sources with known burst oscillation frequencies, our findings largely corroborate previous studies. However, many sources displayed low confidence levels in the oscillation signals, with [sub [sup Z 1 2]] values between 10 and 20. For sources without known oscillation/spin frequencies, we utilized FFT analysis to search for signals across a broad frequency range. This approach revealed potential oscillation signals, with several bursts showing significance levels exceeding 3σ, including those from MAXI J1421-613, XTE J1701-407, XMM J174457-2850.3, Swift J1734.5-3027, IGR J17473-2721, Swift J174805.3-244637, Swift J181723.1-164300, and X 1832-330. [ABSTRACT FROM AUTHOR]

Understanding the spatiotemporal dynamics of formaldehyde (FA) is crucial for elucidating its pathophysiology. In this study, we designed a series of organelle-resolved probes to investigate FA dynamics. By incorporating various organelle anchors into a coumarin hydrazonate, we developed a series of probes with excellent organelle selectivity and FA specificity, enabling rapid and precise sensing of FA in an organelle-resolved way. Leveraging these probes, we captured the spatiotemporal dynamics of native FA in response to exogenous FA or oxidative stress challenges. In particular, we unveiled the distinct responses of various organelles to identical cellular stressors. Moreover, we observed the dynamic response within individual organelles when cells were exposed to stressors for varying durations. We envision these probes will serve as versatile tools for probing FA pathophysiology. [ABSTRACT FROM AUTHOR]

The Xinjiazui gold deposit marks a notable significance in prospecting within the Back-Longmenshan tectonic belt, located on the northwest margin of the Yangtze Block, China. Despite the extensive studies conducted on this deposit, the source of the ore-forming materials remains unclear, leading to ongoing debates regarding the genesis of this deposit. This study analyzed in situ (EPMA and LA-ICP-MS) trace elements and S-Pb isotopes of arsenopyrite, solely from the principal metallogenic stage and paragenetic with native gold. The results show that the gold in arsenopyrite occurs as invisible gold (Au3+), with an average concentration of 9.38 ppm, whereas the concentrations of magma-related elements, such as W, Sn, Mo, and Bi, are very low. The sulfur isotopes (34S) of arsenopyrite range from 8.32‰ to 10.16‰, aligning closely with the deep metamorphic basement (Pt3l). Meanwhile, the lead isotopes in arsenopyrite display characteristics typical of those found in orogenic belts. A comprehensive analysis of the abundance of gold indicated that the metallogenic materials (sulfur and gold) primarily originated from Pt3l. Additionally, the arsenopyrite thermobarometer indicated that the Xinjiazui gold deposit formed in a medium–low-temperature, medium metallogenic environment (5.57–8.69 km), with a sulfur fugacity (log f (S2)) below −8.4. Combined with previous research results, this study proposes that the Xinjiazui gold deposit is a subduction-related mesozonal orogenic gold deposit. In gold prospecting and exploration in the Back-Longmenshan tectonic belt, it is essential to focus on the distribution of brittle-ductile shear zones and location of the quartz veins associated with pyrite and arsenopyrite mineralization. [ABSTRACT FROM AUTHOR]