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The multicore fiber amplifier, as a key component in spatial division multiplexing (SDM) communication systems, presents higher technical difficulty compared to traditional multi-channel single core fiber amplifiers, which has sparked widespread attention. To achieve balance, efficiency, miniaturization, and cost-effectiveness in the performance of multi-core optical fiber amplifiers, we propose an innovative triple cladding 13-core Er/Yb co-doped microstructured fiber (13CEYDMOF). The proposed fiber features an outer cladding with peanut-shaped air holes, which enables uniform excitation of the 13 cores using a single multimode laser pump source within the inner cladding. This approach also prevents damage or aging of the fiber’s outer coating due to the pump laser. Furthermore, the design of Peanut-Shaped Air Holes effectively increases the numerical aperture (NA) of the inner cladding while reducing the outer diameter of the fiber, enhancing the fiber’s mechanical flexibility. To address the coupling difficulties caused by air holes, we bi-directionally pump the 13CEYDMOFA by utilizing a combined technique of the side winding and end pumping. The experimental results show that the 13CEYDMOFA can achieve an average gain of 23.8 dB, a noise figure (NF) of ∼4.6 dB, and an inter-core gain difference of less than 2 dB in the wavelength range of 1529–1565 nm. The in-line amplified transmission experiment demonstrates that the 13CEYDMOFA is well suited for the 13 spatial channels transmission. To the best of our knowledge, this is the first time to realize high performance telecommunication band amplification in a multicore microstructure fiber.

Objective: To investigate the clinical features, endoscopic manifestations, and genetic characteristics of a child with Wiskott-Aldrich syndrome(WAS) and Crohn′s disease, so as to provide reference for clinical diagnosis. Methods: The clinical manifestations, biological indicators, endoscopic characters, therapy, and follow-up of a child with Crohn′s disease combined with WAS were analyzed retrospectively. And literature was searched from PubMed, Wanfang Data, and CNKI. Results: A 6-year-old boy had recurrent abdominal pain, hematochezia for one month, and had perianal abscess for about half a month. He also had thrombocytopenia since infancy. Complete blood cell count showed moderate anemia (Hb 70 g/L) and decreased platelets (77×109/L). The boy had elevated erythrocyte sedimentation rate (71 mm/h) and fecal calprotectin (>1 800 μg/g). Colonoscopy showed multiple ulcers in colon and the pathological examination revealed chronic inflammation in mucosa of the terminal ileum and colon, some of which were accompanied by microabscess and crypt abscesses. The child was diagnosed with Crohn's disease. A splicing mutation (c.777+3_777+6 del GAGT) was identified in the exon 8 of WAS gene by next-generation sequencing. Consequently, the child was definitely diagnosed as WAS combined with Crohn′s disease. There were 9 relevant articles, showing that all 16 patients had childhood-onset inflammatory bowel disease (IBD) (1 day to 14.9 years old), and 10 of them were accompanied by thrombocytopenia. Various treatments, including drugs, surgery, and bone marrow transplantation were required. Seven patients were followed up, and three of them died. Conclusions: For children with IBD, particularly those with very early-onset inflammatory bowel disease, the possibility of monogenic diseases should be taken into account. If a male child with IBD have thrombocytopenia since childhood, the WAS gene should be detected.

Analyzing the current trends and causes of carbon storage changes and accurately predicting future land use and carbon storage changes under different climate scenarios is crucial for regional land use decision-making and carbon management. This study focuses on Beijing as its study area and introduces a framework that combines the Markov model, the Patch-based Land Use Simulation (PLUS) model, and the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model to assess carbon storage at the sub-district level. This framework allows for a systematic analysis of land use and carbon storage spatiotemporal evolution in Beijing from 2000 to 2020, including the influence of driving factors on carbon storage. Moreover, it enables the simulation and prediction of land use and carbon storage changes in Beijing from 2025 to 2040 under various scenarios. The results show the following: (1) From 2000 to 2020, the overall land use change in Beijing showed a trend of "Significant decrease in cropland area; Forest increase gradually; Shrub and grassland area increase first and then decrease; Decrease and then increase in water; Impervious expands in a large scale". (2) From 2000 to 2020, the carbon storage in Beijing showed a "decrease-increase" fluctuation, with an overall decrease of 1.3 Tg. In future carbon storage prediction, the ecological protection scenario will contribute to achieving the goals of carbon peak and carbon neutrality. (3) Among the various driving factors, slope has the strongest impact on the overall carbon storage in Beijing, followed by Human Activity Intensity (HAI) and Nighttime Light Data (NTL). In the analysis of carbon storage in the built-up areas, it was found that HAI and DEM (Digital Elevation Model) have the strongest effect, followed by NTL and Fractional Vegetation Cover (FVC). The findings from this study offer valuable insights for the sustainable advancement of ecological conservation and urban development in Beijing. [ABSTRACT FROM AUTHOR]

Excavating highly efficient and cost‐effective non‐noble metal single‐atom catalysts for electrocatalytic CO2 reduction reaction (CO2RR) is of paramount significance. However, the general and universal strategy for designing atomically dispersed metals as accessible active sites is still in its infancy. Herein, we reported a general sol–gel pore‐confined strategy for preparing a series of isolated transition metal single atoms (Fe/Co/Ni/Cu) anchored on nitrogen‐doped carbon matrix. Benefiting from synergistic effect of M‐N4 coordination and neighboring N doping, the Fe‐N4‐C catalyst exhibited superior capability with a Faradaic efficiency of 96.9%, achieving highly stable electrocatalytic activity for more than 20 h. Density functional theory (DFT) calculations further revealed the changes in the dxz orbital of Fe, with a decrease in the out‐of‐plane component. Thus, a lower free energy barrier (ΔG) in thermodynamic pathway and the accelerated proton transfer to *COOH in kinetic pathway both enhanced electrocatalytic process. [ABSTRACT FROM AUTHOR]

The utilization of the photo catalytic activation of permonosulfate (PMS) for the combined breakdown of pollutants has become a focal point in research. Layered double hydroxides (LDHs) have a unique layered structure which is conducive to the adsorption and diffusion of reactants, and can provide more active sites for photocatalytic reactions. The anions between the layers can be exchanged with a variety of substances so that specific catalytically active species can be introduced as needed. LDHs themselves have certain catalytic activity, which can produce synergistic catalysis between LDHs and the supported photocatalytic active substances, and further improve the degradation effect of antibiotics. In actual wastewater treatment, LDHs as a catalyst carrier have a good application prospect. However, the poor activation effect is attributed to the low separation efficiency of catalyst carriers and insufficient active sites. In this study, a dual active site system consisting of Co and Fe, known as CoFe-LDHs@MoS2, was developed as a catalyst to facilitate the synergistic degradation of norfloxacin (NOF) by PMS under visible light. The findings demonstrate that the material possesses an effective capacity for the synergistic degradation of NOF. A comprehensive investigation was conducted to assess the impact of different catalysts, PMS dosage, degradation systems (Vis, PMS, or Vis PMS), catalyst dosage, NOF concentration, pH, and cycle times on the degradation performance. The active free radicals, degradation pathways, and intermediate toxicity were elucidated through capture experiments, Electron Paramagnetic Resonance Spectrometer (ESR) analysis, a liquid mass spectrometry (LC-MS) toxicity assessment, and theoretical calculations. This research offers a novel approach for designing catalysts with exposed high activity sites for the effective removal of NOF from environmental water. [ABSTRACT FROM AUTHOR]