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关键词： Small for gestational age   Short stature   Insulin-like growth factor 1 receptor   Cluster analysis  

摘要： Children born small for gestational age (SGA) who fail to experience catch-up growth often remain short-statured with heterogeneous etiologies, including genetic factors. This study aimed to investigate Insulin-like Growth Factor 1 Receptor (IGF1R) gene alterations and their clinical relevance in 66 Korean children born SGA with persistent short stature. All the subjects underwent detailed phenotyping and molecular analyses. Two patients carried heterozygous deletions encompassing the entire IGF1R gene, as confirmed by chromosomal microarray analysis. Both patients exhibited advanced bone age, with one showing a favorable response to growth hormone therapy. Additionally, 14 variants of uncertain significance were identified, with one rare missense variant (c.158C>T, ***53Met) showing a high predicted pathogenicity. Subgroup analysis showed that severe SGA was associated with lower mid-parental height, and those with an insulin-like growth factor 1 standard deviation score of >= 0 had less bone age delay, but no clear auxological differences were observed between subgroups. These patterns, although not definitive, may help to identify SGA-short children who warrant further evaluation for IGF1R-related growth impairment. Exploratory clustering revealed two subgroups but failed to show distinct phenotypic separation. Although no strong genotype-phenotype correlations were observed, this study highlights the potential clinical value of identifying IGF1R deletions and suggests that molecular and phenotypic profiling may offer hypothesisgenerating insights into SGA-related growth disorders. Our findings underscore the importance of integrating genetic screening into the diagnostic workup for children born SGA with unexplained growth failure, and the need for future studies to functionally characterize rare IGF1R variants.

关键词： Immune response   Large yellow croaker   PAAR-1   Pathogenicity   Pseudomonas plecoglossicida  

摘要： Pseudomonas plecoglossicida is a pathogen bacterium responsible for visceral white spot disease (VWND) in Large Yellow Croakers (Larimichthys crocea), causing significant economic losses in commercial fish farms. The proline-alanine-alanine-arginine repeats protein (PAAR) is a core component of the spike structure in the type VI secretion system (T6SS), which injects toxic effectors into host and contributes to bacterial virulence. However, the role of the PAAR gene in P. plecoglossicida and its impact on bacterial infection and host immune responses remain unexplored. In this study, PAAR-1 was identified for the first time in P. plecoglossicida as an effector gene within the T6SS-1 gene cluster, which is regulated and secreted by T6SS-1. The P. plecoglossicida mutant strain (ΔPAAR-1) and its complementary strain (C-ΔPAAR-1) were constructed for subsequent investigation. Compared to the wild-type strain, ΔPAAR-1 exhibited reduced biofilm formation, adhesion, total antioxidant capacity, and secretion of T6SS core protein Hcp-1. In vitro, ΔPAAR-1 showed decreased survival rates in Large Yellow Croaker macrophage cell line (LYC-FM) due to impaired oxidative stress tolerance. In vivo, infection with ΔPAAR-1 led to a significant reduction in mortality, bacterial colonization, and the formation of spleen nodules in Large Yellow Croakers. Comparative transcriptome analysis revealed that PAAR-1 predominantly influences the host Toll-like receptor (TLR) signaling pathway and apoptosis by upregulating the expression of plasma membrane-associated TLRs, including TLR1, TLR2, and TLR5, while downregulating the expression of endosomal TLRs like TLR3, TLR7, TLR8, and TLR9, along with its downstream molecules such as MyD88 and TRAF3. Additionally, knockout PAAR-1 downregulates a

关键词： Aeromonas hydrophila   Colonization   Fibroblast-like cells   Green fluorescent protein   Pelodiscus sinensis  

摘要： The Chinese soft-shelled turtle (Pelodiscus sinensis) is a crucial economically significant aquatic species, yet its aquaculture is severely impacted by disease-related challenges. Among these, Aeromonas hydrophila stands out as one of the most prevalent pathogenic bacteria, responsible for the highest diversity of disease manifestations and detection rates in farmed P. sinensis. In this study, a pathogenic strain A. hydrophila PS-1 from diseased P. sinensis was isolated and identified. A green fluorescent protein (GFP) labeled PS-1 (PS-1/GFP) was constructed with the pAPR-EGFP plasmid. The growth, motility, and pathogenicity of PS-1/GFP showed no difference from that of the wild type strain. After artificial infection, green fluorescence was only observed in the intestine and liver in a paraffin section at 72 h of infection, which indicated that PS-1 infection exhibited tissue specificity. Accordingly, the colonization sites of PS-1 in P. sinensis were intestine and liver, with bacterial loads reaching as high as 5 × 10⁹ CFU/g and 7 × 10⁸ CFU/g, respectively. Moreover, PS-1 could internalize into intestinal fibroblast-like cells and induce similar cell morphological changes akin to pyroptosis. This work established methodological tools and fundamental insights for investigating diseases in P. sinensis, and laid the groundwork for further elucidation of the pathogen-host interaction mechanisms between A. hydrophila and P. sinensis.

关键词： Chinese soft-shelled turtles Pelodiscus sinensis   Hibernation   Intestine   Proline  

摘要： The object of this study was to assess the impact of proline (Pro) supplementation on mediating hibernation induced intestinal barrier dysfunction in turtle and to explore the underling mechanisms. Pelodiscus sinensis were given a simulated hibernation experiment for 4 weeks, followed by feeding the control (Con) diet and Pro diet for 4 weeks. Results showed that the turtles fed of Pro diet significantly enhanced the feed intake and intestinal Pro deposition, while increased the villus height, crypt depth and the ratio of villus height to crypt depth in intestine of turtles. Pro significantly facilitated the conversion of intestinal type II and III goblet cells to type I goblet cells, and markedly upregulated the expression of muc-2, zo-1, claudin-1, claudin-3, the key gene associated with the intestinal barrier, as well as restrained the expression of mlck. Moreover, Tunel-immunohistochemical analysis showed that Pro diet significantly reduced the number of intestinal late apoptotic cell, and levels of pro-apoptosis and pro-inflammation related genes in Pro treatment were significantly lowered than those in Con treatment. Furthermore, Nf-κB p65 serves as a pivotal transcription factor in activating apoptosis and inflammation, and its expression can be regulated by Nrf2/HO-1. Pro significantly upregulated the protein levels of total-Nrf2, nuclear-Nrf2, and HO-1, while simultaneously suppressing the phosphorylation of NF-κB p65 in the intestine of turtles. These findings revealed the underling mechanism of action of Pro in hibernation stress of P. sinensis, confirming that Pro increased Nrf2 and HO-1 that, which subsequently suppresses the Nf-κB p65 in intestine thereby reducing inflammation and apoptosis, and thus alleviated intestinal tight junction dysfunction and barrier damage of P. sinensis caused by hibernation.

摘要： It was recently proved that every claw-free cubic graph admits a $(1,1,2,2)$-packing coloring—that is, its vertex set can be partitioned into two 1-packings and two 2-packings. This result was established by Brešar et al. (2025). In this paper, we provide a simpler and shorter proof.

关键词： Half thresholding algorithms   Inverse problem   L1/2 regularization   Preconditioning technique  

摘要： The L_1/2 regularization plays a crucial role in promoting sparsity of the solution in the optimization models. The half thresholding algorithm, which is derived based on the threshold representation theorem, serves as an efficient solver for the non-convex L_1/2 regularization problem. However, an excessively large matrix norm leads to an excessively small threshold, thereby impeding the convergence rate of half thresholding algorithm. In this study, we introduce two preconditioning matrices in the L_1/2 regularization model. One matrix enhances convergence by improving the algebraic properties of the matrix, while another adjusts the threshold and value of the regularization parameter automatically in every iteration. In particular, when the sparsity of the solution is unknown, the exact number of nonzero components can be approached iteratively. Furthermore, we expedite the half thresholding iterative algorithm using the Nesterov acceleration technique and provide the corresponding convergence results. We validate both the effectiveness and efficiency of our proposed algorithm through the examples in computational spectrometer reconstruction.

关键词： Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine   Phase transition   Rapid compression   Time-resolved Raman spectroscopy  

摘要： We present time-resolved Raman spectroscopy measurements to study the structural response of $\beta$-HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) up to 20 GPa and over compression rates ranging from 0.03 to 1.07 GPa/s using a dynamic diamond anvil cell. Similar to previous static high pressure results, two phase transitions of $\beta \to \zeta$ and $\zeta \to \varepsilon$ were observed at approximately 5.7 and 9.5 GPa, respectively, regardless of the compression rate. This can be attributed to the fast transition kinetics of a displacive transition mechanism. Further, when decompressed to ambient pressure, all the phase transitions are reversible and there is no chemical reaction. Our results clearly indicate that little effect of the investigated compression rates on the structural response of $\beta$-HMX, suggesting the behavior of $\beta$-HMX during manufacture, transport or handling can be molded using the existing static high pressure data, which will contribute to the prediction of the safety of $\beta$-HMX based explosives and development of kinetic initiation models.

关键词： Antiferromagnetic transition   Electrical transport   High pressure   Phase transition   Raman spectroscopy  

摘要： Single -crystal Co_1/3NbS₂ was successfully synthesized under high-pressure and high-temperature conditions and was systematically characterized via structural, component, and magnetic measurements. Magnetization measurements revealed a paramagnetic to antiferromagnetic (PM-AFM) phase transition at 28.4 K. Electrical conductivity, Raman spectroscopy and X-ray diffraction measurements were performed on Co_1/3NbS₂ at high pressures (up to 46.1 GPa). We observed an anomaly (an inflection) in the temperature dependence of the resistivity at 4.4 GPa, and the inflection point shifted towards higher temperatures with increasing pressure. The abnormal resistivity above 2.1 GPa was closely related to the complete suppression of magnetic order. The electrical resistivity tended to change with increasing pressure at 9.0 and 15.0 GPa. The spectroscopic and crystallographic results demonstrated a redshift in the v₁’ and v₂ peaks, indicating a potential topological phase transition at approximately 9.7 GPa. Moreover, an isostructural phase transition occurred in the material at 15.3 GPa, accompanied by the splitting of several Raman peaks. Above 23.1 GPa, the Raman spectrum exhibited an abrupt change, which was associated with a pressure-induced volume change in the material.

关键词： 1,1,4,4-tetracyanobutadiene   Dicyanoquinodimethane   Infrared photoresponsivity   Organic photodetector   Triphenylamine  

摘要： In this study, the effect of electron-withdrawing electron accepting groups, i.e. 1,1,4,4-tetracyanobutadiene and dicyanoquinodimethane, on the optoelectrical properties of four newly developed derivatives of triphenylamine having methoxy and ethynylbenzene groups is investigated. The molecular structure–property relationships are analyzed from the perspective of potential applications of the compounds as non-fullerene absorbers in near-infrared organic photodetectors. The developed molecular design enables to tune the optical band gaps from 1.24 to 2.0 eV, spanning various red and near-infrared regions. Charge-extracting properties are influenced by various energy levels, with ionization potentials ranging from 5.69 to 6.07 eV and electron affinities varying from 4.07 to 4.74 eV. Either hole or electron mobility values estimated by the tools of time-of-flight and charge carrier extraction by linearly increasing voltage are in the wide range of 8 × 10⁻⁶-4.6 × 10⁻⁴ cm² Vs at the electric field of 9.6 × 10⁵ V/cm. The solitary and binary organic photodetectors are fabricated to demonstrate the potential of the compounds for photodetection. The photoresponsivity value of 5.5 × 10⁻³ A/W and shot-noise-limited specific detectivity of 0.93 × 10¹¹ Jones at 850 nm are achieved using the developed non-fullerene low-molar-mass acceptors as red/near-infrared absorbers. The use of hosts with high hole mobility values decreased the rising and falling times of the photo-responses to under 10 μs in binary organic photodetectors.

关键词： Excited state intramolecular proton transfer   High-lying reverse intersystem crossing   OLEDs   TD-DFT  

摘要： Materials that simultaneously enable excited-state intramolecular proton transfer (ESIPT) and high-lying reverse intersystem crossing (hRISC) can effectively circumvent the energy transfer challenges in white organic light-emitting diodes (WOLEDs) while offering high exciton utilization, making them ideal candidates for multi-emissive layers in WOLEDs. This study systematically investigates the ESIPT and hRISC properties of 2-(benzo[d]thiazol-2-yl)-4-(pyren-1-yl)phenol (PyHBT) and their solvent effects using density functional theory/time-dependent DFT (DFT/TD-DFT). Solvents exert a minor influence on this process, but fluorescence intensity is positively correlated with polarity. Hole-electron analysis indicates that the charge transfer characteristics of Enol*-form emission result in lower fluorescence intensity compared to Keto*-form emission, and the Enol* forms are more conducive to reverse intersystem crossing (RISC). The pronounced separation of HOMO-LUMO further confirms its hRISC potential. The smaller Enol*-form singlet-triplet energy gap indicates that hRISC occurs between S₁ and T₃ states, with its rate decreasing as solvent polarity increases. Collectively, this study deepens the comprehension of synergistic ESIPT-hRISC mechanism and offers valuable guidelines for designing next-generation WOLED materials.