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Broad-area 976 nm semiconductor lasers have garnered widespread attention for their applications in generating high-power 488 nm blue laser light and as pump sources for solid-state and ytterbium-doped fiber lasers. Nevertheless, these lasers exhibit a wide gain bandwidth, short cavity length, and usually use the natural cleavage surface as the output window, resulting in a broad emitting spectrum in free-running state. We investigated a high-power narrow-linewidth 976 nm edge emitting broad area semiconductor laser (EEL) through external cavity feedback technology by employing a transmission grating as the dispersive element. This configuration achieved a high output power of 11 W and a spectral linewidth of 0.36 nm at 976 nm, corresponding to an intracavity power of 15.7 W. It provided a more flexible cavity structure for direct frequency doubling of the semiconductor laser to generate a high power of 488 nm blue laser.

Abstract During the past few decades, pyroelectric sensors have attracted extensive attention due to their prominent features. However, their effectiveness is hindered by low electric output. In this study, the laser processed lithium niobate (LPLN) wafers are fabricated to improve the temperature–voltage response. These processed wafers are utilized to construct pyroelectric sensors as well as human–machine interfaces. The laser induces escape of oxygen and the formation of oxygen vacancies, which enhance the charge transport capability on the surface of lithium niobate (LN). Therefore, the electrodes gather an increased quantity of charges, increasing the pyroelectric voltage on the LPLN wafers to a 1.3 times higher voltage than that of LN wafers. For the human–machine interfaces, tactile information in various modes can be recognized by a sensor array and the temperature warning system operates well. Therefore, the laser modification approach is promising to enhance the performance of pyroelectric devices for applications in human–machine interfaces.

Due to continuous plantation of poplar, its growth and biomass accumulation may be negatively affected by the accumulation of allelochemicals such as para-hydroxybenzoic acid (pHBA) in soil. As photosynthesis is the most fundamental process in plants, it can be negatively impacted by pHBA stress. Therefore, it is crucial to improve photosynthetic capacity under pHBA stress to facilitate poplar plant growth. The mitogen-activated protein kinase (MAPK) cascade pathway is widely involved in environmental stress responses in plants. However, the regulation mechanisms of photosynthesis-related pathways by MAPK pathway genes under pHBA stress are still unclear. In this study, through transcriptome analysis and weighted gene co-expression network analysis, we observed that PeMPK7 overexpression in poplar can regulate the expression of photosynthesis-related genes and transcription factor genes, namely, WRKY1, WRKY33, and ERF3, during the early stage of pHBA stress. In addition, PeMPK7 can improve photosynthesis in poplar under long-term pHBA stress. Moreover, yeast two-hybrid and pull-down assays confirmed the interaction between PeMPK7 and PeMKK7/10. Based on these results, a schematic diagram of the pathways involved in the regulation of photosynthesis by PeMPK7 was constructed. This study provided novel insights into the molecular mechanisms of regulation of pHBA stress via MAPK cascade pathway.

Abstract Defect‐assisted heteroatom doping can effectively enhance the intrinsic transfer characteristics of carriers in the crystal structure, which advantages over fast and efficient charge storage. In this work, a three‐dimensional self‐supporting titanium dioxide nanoparticle rich in bulk vacancies (L‐TiOx) on titanium substrate is synthesized by pulsed laser. Different from the surface vacancies, the bulk oxygen defects of L‐TiOx cause a uniform and bulk phosphorus (P) doping with a high concentration of ~5.71 at %, which endows the elevated electronic conductivity, and accelerates the transport of Na+. The obtained P‐doped L‐TiOx (LP‐TiOx) as an anode material in sodium‐ion batteries (SIBs) provides a reversible capacity of 400 mAh g−1 at 200 mA g−1, outstanding rate capability of 196 mAh g−1 at 10,000 mA g−1, and maintains stable performance over 1000 cycles. In situ X‐ray diffraction and ex situ high‐resolution transmission electron microscopy show that LP‐TiOx exhibits robust mechanical behavior with almost no lattice change under (de)sodiation. This work supplies a novel idea for high‐concentration bulk heteroatoms doping to enhance the electrochemical performance of SIBs.

Abstract In response to genotoxic stress‐induced DNA damage, TopBP1 mediates ATR activation for signaling transduction and DNA damage repair. However, the detailed molecular mechanism remains elusive. Here, using unbiased protein affinity purification and RNA sequencing, it is found that TopBP1 is associated with pre‐ribosomal RNA (pre‐rRNA). Pre‐rRNA co‐localized with TopBP1 at DNA double‐strand breaks (DSBs). Similar to pre‐rRNA, ribosomal proteins also colocalize with TopBP1 at DSBs. The recruitment of TopBP1 to DSBs is suppressed when cells are transiently treated with RNA polymerase I inhibitor (Pol I‐i) to suppress pre‐rRNA biogenesis but not protein translation. Moreover, the BRCT4‐5 of TopBP1 recognizes pre‐rRNA and forms liquid–liquid phase separation (LLPS) with pre‐rRNA, which may be the molecular basis of DSB‐induced foci of TopBP1. Finally, Pol I‐i treatment impairs TopBP1‐associated cell cycle checkpoint activation and homologous recombination repair. Collectively, this study reveals that pre‐rRNA plays a key role in the TopBP1‐dependent DNA damage response.

Mitogen-activated protein kinase (MAPK) plays a crucial role in plant stress response. Poplar is one of the most important afforestation and timber species and inevitably encounters allelopathy effects during continuous cropping. para-hydroxybenzoic acid (pHBA) is a primary soil allelochemical, which can restrict the growth and biomass of poplar. However, the involvement of MAPKs in the underlying physiological and molecular regulatory mechanisms in response to pHBA stress remains unclear. In this study, PeMPK17, a gene encoding a group D MAPK, was cloned from Populus × euramericana. PeMPK17 protein was localized in both nucleus and plasma membrane. Quantitative real-time polymerase chain reaction analysis demonstrated that PeMPK17 expression in poplar increased when treated with pHBA, PEG, and H2O2. Exogenous pHBA and H2O2 induced PeMPK17 expression mediated by reactive oxygen species (ROS). The transgenic poplar plants overexpressing PeMPK17 demonstrated attenuated phenotypic injury, higher relative water content in leaves, and lower ion leakage under pHBA stress. In transgenic poplar, the activity and expression of antioxidant enzymes including superoxide dismutase, peroxidase, and catalase increased, while the content of H2O2, O2·-, and malondialdehyde decreased. These results suggested that PeMPK17 protects cell membranes from oxidative damage by removing excess ROS. In addition, overexpression of PeMPK17 promoted osmoprotectant accumulation including soluble sugar and free proline, which may aid in the regulation of ROS balance under pHBA treatment. Furthermore, the interaction between PeMPK17 and PeMKK7 was confirmed. Collectively, these data identify the molecular mechanisms and signal pathways associated with PeMPK17 that regulate pHBA response in poplar.

To assess the diversity of bacterial taxa in Antarctic soils and obtain novel microbial resources, 15 samples from 3 sampling sites (DIS5, GWS7, FPS10) of South Shetland Islands and 2 sampling sites (APS18, CIS17) of Antarctic Peninsula were collected. High-throughput sequencing (HTS) of 16S rRNA genes within these samples was conducted on an Illumina Miseq platform. A total of 140,303 16S rRNA gene reads comprising 802 operational taxonomic units (OTUs) were obtained. After taxonomic classification, 25 phyla, 196 genera, and a high proportion of unidentified taxa were detected, among which seven phyla and 99 genera were firstly detected in Antarctica. The bacterial communities were dominated by Actinomycetota (40.40%), Pseudomonadota (17.14%), Bacteroidota (10.55%) and Chloroflexota (10.26%). Based on the HTS analyses, cultivation-dependent techniques were optimized to identify the cultivable members. A total of 30 different genera including 91 strains were obtained, the majority of which has previously been reported from Antarctica. However, for the genera Microterricola, Dyadobacter, Filibacter, Duganella, Ensifer, Antarcticirhabdus and Microvirga, this is the first report in Antarctica. In addition, seven strains represented novel taxa, two of which were psychropoilic and could be valuable resources for further research of cold-adaptability and their ecological significance in Antarctica.

Syn-subduction basins bear significant implications to understand tectonic evolution of any fossil subduction zone. The late Paleozoic to early Mesozoic (Paleo-Tethyan) tectonics of the eastern and southeastern Tibetan Plateau (i.e., the Sanjiang Orogenic Belt) is featured by ocean-continent subduction systems. A huge pile of volcanic-absent sedimentary succession developed in the middle segment of the Sanjiang orogenic belt, its age and tectonic nature remain unclear. Detailed geological mapping and zircon U-Pb dating results demonstrate that the early Late Triassic volcanic-absent succession comprises the nonmarine Maichuqing Formation in the lower part and the shallow marine Sanhedong Formation in the upper part. The Maichuqing Formation consists of coarse to fine-grained sandstone, siltstone and mudstone with abundant basal erosional surfaces, trough and planar cross-beddings, ripples, mudcracks, and plant fragments. The Sanhedong Formation comprises predominantly bioclastic limestones interlayered with marl, calcareous-muddy siltstone, and calcareous sandstone with abundant bivalve fossils. Syn-sedimentation deformation structures, such as slump folds and associated normal faults are common, suggesting intense tectonism during deposition. Synthesizing sedimentary data, paleocurrent and provenance results, combined with other available data, demonstrate that the volcanic-absent succession deposited within a retro-foreland basin along the rear part of the Permian-Triassic Jomda-Weixi-Yunxian arc in response to flat-subduction of the Paleo-Tethyan Ocean during the early Late Triassic time.

RIG-I plays important roles in pathogen sensing and activation of antiviral innate immune responses in response to RNA viruses. RIG-I-mediated signaling must be precisely controlled to maintain innate immune signaling homeostasis. Previous studies demonstrated that lysine 63 (K63)-linked polyubiquitination of RIG-I is vital for its activation, but the mechanisms through which RIG-I is deubiquitinated to control innate immune responses are not well understood. Here we identified USP27X as a negative regulator of antiviral signaling in response to RNA viruses through siRNA library screening. Further functional studies indicated that USP27X negatively modulated RIG-I-mediated antiviral signaling in a deubiquitinase-dependent manner. Mechanistically, we found that USP27X removed K63-linked polyubiquitin chains from RIG-I to negatively modulate type I interferon signaling. Collectively, these studies uncover a novel negative regulatory role of USP27X in targeting RIG-I to balance innate immune responses.

Successive indentations of Eurasia by India have led to the Tibet-Himalaya E–W orthogonal collision belt and the SE Tibetan Plateau N–S oblique collision belt along the frontal and eastern edges of the indenter, respectively. The belts exhibit distinctive lithospheric structures and tectonic evolutions. A comprehensive compilation of available geological and geophysical data reveals two sudden tectonic transitions in the early Eocene and the earliest Miocene, respectively, of the tectonic evolution of the orthogonal belt. Synthesizing geological and geochronological data helps us to suggest a NEE–SWW trending, ~450 km-long, ~250 km-wide magmatic zone in SE Tibet, which separates the oblique collision belt (eastern and SE Tibet) into three segments of distinctive seismic structures including the mantle and crust anisotropies. The newly identified Yongping basin is located in the central part of the magmatic zone. Geochronological and thermochronological data demonstrate that (1) this basin and the magmatic zone started to form at ~48 Ma likely due to NNW–SSE lithosphere stretching according to the spatial coincidence of the concentrated mantle-sourced igneous rocks on the surface with the seismic anomalies at depth; and (2) its fills was shortened in the E–W direction since ~23 Ma. These two dates correspond to the onset of the first and second tectonic transitions of the orthogonal collision belt. As such, both the orthogonal and oblique belts share a single time framework of their tectonic evolution. By synthesizing geological and geophysical data of both collision belts, the indenting process can be divided into three stages separated by two tectonic transitions. Continent–continent collision as a piston took place exclusively during the second stage. During the other two stages, the India lithosphere underthrust beneath Eurasia.

Syndecans are transmembrane proteoglycans implicated in diverse cellular activities. Here the authors show that Syndecan-4 via its cytosolic domain negatively regulates antiviral immunity by enhancing RIG-I interaction with a deubiquitinating enzyme CYLD, thus inhibiting the activating K63-linked RIG-I ubiquitination.

Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses1. The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset2-5. Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed.

Background: Posttraumatic stress disorder (PTSD) is associated with the development of dementia. However, the link between PTSD and preclinical Alzheimer's disease pathology (amyloid β [Aβ]) remains controversial. Moreover, the correlation between the severity of PTSD with Aβ levels remains unknown. Methods: This cross-sectional study sought to investigate the associations of PTSD symptoms with global and regional brain Aβ burden. To this end, data were obtained from participants in the Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) Study. In addition, we explored the association between the severity of PTSD symptoms and Aβ levels. Results: A total of 4,228 participants aged 65 to 85 years were included in the final analysis. The results showed that PTSD symptoms were significantly associated with higher global Aβ levels (1.15 ± 0.20 vs. 1.09 ± 0.19; β = 0.056; p < 0.001), after adjusting for covariates. The association between PTSD symptoms and Aβ levels was not affected by sex, age, ApoE genotype, or psychiatric diseases. Similarly, PTSD symptoms were significantly associated with Aβ levels in all subregions, including the anterior cingulate, posterior cingulate, parietal cortex, precuneus, temporal cortex, and frontal cortex. In addition, the group with severe PTSD symptoms (1.22 ± 0.24) exhibited higher global Aβ levels than the groups with moderate (1.14 ± 0.19) or mild (1.12 ± 0.20) symptoms or the control (1.08 ± 0.18), with p < 0.001. Conclusion: The findings imply a close relationship between PTSD and brain Aβ levels, irrespective of sex, age, ApoE genotype, or psychiatric diseases. More well-designed studies are needed to further explore the relationship and mechanism underlying the association between PTSD and Aβ burden. [ABSTRACT FROM AUTHOR]