High-fidelity imaging of a tumour-associated lysosomal enzyme with an acceptor engineering-boosted near-infrared fluorescent probe.

To facilitate the understanding of the dynamic distribution and activity of lysosomal enzymes, it is highly desirable to develop high-fidelity near-infrared (NIR) activatable fluorescent probes. Here, we propose a general acceptor engineering strategy to construct NIR probes with lysosome-targeting capability. Upon isosteric replacement and additional functionalization, the ß-gal-activatable probe OELyso-Gal exhibited excellent lysosome-targeting capability and favorable responsive performance to the enzyme of interest. Notably, the steric hindrance effect from acceptor engineering is modest, which renders the probe unprecedented affinity to enzymes. Upon the introduction of acceptor engineering, the lysosome-targeting probe became more sensitive to ß-gal in cells and tissues, boosting the discrimination of high ß-gal-expressing ovarian cancer tumours from low ß-gal-expressing tissues. Furthermore, the superiority of OELyso-Gal was validated in real-time visualization of ovarian cancer in tumour-bearing mice. This elegant acceptor engineering strategy provides inspirational insights into the development of customized fluorescent probes for monitoring disease-associated biomarkers within subcellular organelles.

4-Octyl itaconate inhibits inflammation via the NLRP3 pathway in neuromyelitis optica spectrum disorders.

OBJECTIVE: Neuromyelitis optica spectrum disorders (NMOSD) are rare inflammatory astrocytic diseases of the central nervous system (CNS). The roles of immune response gene-1 (IRG1) and the IRG1-itaconic acid-NLRP3 inflammatory pathway in the pathogenesis of NMOSD and the effects of 4-octyl itaconate (4-OI) on the NLRP3 inflammatory pathway in NMOSD are unclear. This study aimed to determine the role of IRG1 and the activation status of the NLRP3 inflammatory pathway in acute-onset NMOSD and to investigate the inhibitory effects of 4-OI on NLRP3 inflammasome activation via the IRG1-itaconic acid-NLRP3 pathway in monocytes and macrophages by using in vitro models. METHODS: Peripheral blood mononuclear cells (PBMCs) and serum were collected from patients with acute NMOSDs and healthy controls (HC), followed by monocyte typing and detection of the expression of NLRP3-related inflammatory factors. Subsequently, the effects of 4-OI on the IRG1-itaconic acid-NLRP3 pathway were investigated in peripheral monocytes from patients with NMOSD and in macrophages induced by human myeloid leukemia mononuclear cells (THP-1 cells) via in vitro experiments. RESULTS: Patients with acute NMOSD exhibited upregulated IRG1 expression. In particular, the upregulation of the expression of the NLRP3 inflammasome and proinflammatory factors was notable in monocytes in acute NMOSD patients. 4-OI inhibited the activation of the IRG1-itaconic acid-NLRP3 inflammatory pathway in the PBMCs of patients with NMOSD. INTERPRETATION: 4-OI could effectively inhibit NLRP3 signaling, leading to the inhibition of proinflammatory cytokine production in patients with NMOSD-derived PBMCs and in a human macrophage model. Thus, 4-OI and itaconate could have important therapeutic value for the treatment of NMOSD in the future.

Exploring the Link Between Autophagy-Lysosomal Dysfunction and Early Heterotopic Ossification in Tendons.

Heterotopic ossification (HO), the pathological formation of bone within soft tissues such as tendon and muscle, is a notable complication resulting from severe injury. While soft tissue injury is necessary for HO development, the specific molecular pathology responsible for trauma-induced HO remains a mystery. The previous study detected abnormal autophagy function in the early stages of tendon HO. Nevertheless, it remains to be determined whether autophagy governs the process of HO generation. Here, trauma-induced tendon HO model is used to investigate the relationship between autophagy and tendon calcification. In the early stages of tenotomy, it is observed that autophagic flux is significantly impaired and that blocking autophagic flux promoted the development of more rampant calcification. Moreover, Gt(ROSA)26sor transgenic mouse model experiments disclosed lysosomal acid dysfunction as chief reason behind impaired autophagic flux. Stimulating V-ATPase activity reinstated both lysosomal acid functioning and autophagic flux, thereby reversing tendon HO. This present study demonstrates that autophagy-lysosomal dysfunction triggers HO in the stages of tendon injury, with potential therapeutic targeting implications for HO.

Identification of arginine-vasopressin receptor 1a (Avpr1a/AVPR1A) as a novel candidate gene for chronic visceral pain sheds light on the potential role of enteric neurons in the development of visceral hypersensitivity.

Chronic abdominal pain in the absence of ongoing disease is the hallmark of disorders of gut-brain interaction (DGBIs), including irritable bowel syndrome (IBS). While the etiology of DGBIs remains poorly understood, there is evidence that both genetic and environmental factors play a role. In this study, we report the identification and validation of Avpr1a as a novel candidate gene for visceral hypersensitivity (VH), a primary peripheral mechanism underlying abdominal pain in DGBI/IBS. Comparing two C57BL/6 (BL/6) substrains (C57BL/6NTac and C57BL/6J) revealed differential susceptibility to the development of chronic VH following intrarectal zymosan (ZYM) instillation, a validated preclinical model for post-inflammatory IBS. Using whole genome sequencing, we identified a SNP differentiating the two strains in the 5' intergenic region upstream of Avpr1a, encoding the protein arginine-vasopressin receptor 1A (AVPR1A). We used behavioral, histological, and molecular approaches to identify distal colon-specific gene expression and neuronal hyperresponsiveness covarying with Avpr1a genotype and VH susceptibility. While the two BL/6 substrains did not differ across other gastrointestinal (GI) phenotypes (e.g., fecal water retention), VH-susceptible BL/6NTac mice had higher colonic Avpr1a mRNA and protein expression. These results parallel findings that patients' colonic Avpr1a mRNA expression corresponded to higher pain ratings. Moreover, neurons of the enteric nervous system were hyperresponsive to the AVPR1A agonist AVP, suggesting a role for enteric neurons in the pathology underlying VH. Taken together, these findings implicate differential regulation of Avpr1a as a novel mechanism of VH-susceptibility as well as a potential therapeutic target specific to VH. PERSPECTIVE: This article presents evidence of Avpr1a as a novel candidate gene for visceral hypersensitivity in a mouse model of irritable bowel syndrome. Avpr1a genotype and/or tissue-specific expression represents a potential biomarker for chronic abdominal pain susceptibility.

A stacking-based algorithm for antifreeze protein identification using combined physicochemical, pseudo amino acid composition, and reduction property features.

Antifreeze proteins have wide applications in the medical and food industries. In this study, we propose a stacking-based classifier that can effectively identify antifreeze proteins. Initially, feature extraction was performed in three aspects: reduction properties, scalable pseudo amino acid composition, and physicochemical properties. A hybrid feature set comprised of the combined information from these three categories was obtained. Subsequently, we trained the training set based on LightGBM, XGBoost, and RandomForest algorithms, and the training outcomes were passed to the Logistic algorithm for matching, thereby establishing a stacking algorithm. The proposed algorithm was tested on the test set and an independent validation set. Experimental data indicates that the algorithm achieved a recognition accuracy of 98.3 %, and an accuracy of 98.5 % on the validation set. Lastly, we analyzed the reasons why numerical features achieved high recognition capabilities from multiple aspects. Data dimensionality reduction and the analysis from two-dimensional and three-dimensional views revealed separability between positive and negative samples, and the protein three-dimensional structure further demonstrated significant differences in related features between the two samples. Analysis of the classifier revealed that Hr*Hr, HrHr, and Sc-PseAAC_1, 188D(152,116,57,183) were among the seven most important numerical features affecting algorithm recognition. For Hr*Hr and HrHr, supportive sequence level evidence for the reduction dictionary was found in terms of conservation area analysis, multiple sequence alignment, and amino acid conservative substitution. Moreover, the importance of the reduction dictionary was recognized through a comparative analysis of importance before and after the reduction, realizing the effectiveness of the dictionary in improving feature importance. A decision tree model has been utilized to discern the distinctions between dipeptides associated with the physical and chemical properties of His(H), Iso(I), Leu(L), and Lys(K) and other dipeptides. We finally analyzed the other seven features of importance, and data analysis confirmed that hydrophobicity, secondary structure, charge properties, van der Waals forces, and solvent accessibility are also factors affecting the antifreeze capability of proteins.

Research on improved YOLOv8n based potato seedling detection in UAV remote sensing images.

Introduction: Accurate detection of potato seedlings is crucial for obtaining information on potato seedlings and ultimately increasing potato yield. This study aims to enhance the detection of potato seedlings in drone-captured images through a novel lightweight model. Methods: We established a dataset of drone-captured images of potato seedlings and proposed the VBGS-YOLOv8n model, an improved version of YOLOv8n. This model employs a lighter VanillaNet as the backbone network in-stead of the original YOLOv8n model. To address the small target features of potato seedlings, we introduced a weighted bidirectional feature pyramid network to replace the path aggregation network, reducing information loss between network layers, facilitating rapid multi-scale feature fusion, and enhancing detection performance. Additionally, we incorporated GSConv and Slim-neck designs at the Neck section to balance accuracy while reducing model complexity. Results: The VBGS-YOLOv8n model, with 1,524,943 parameters and 4.2 billion FLOPs, achieves a precision of 97.1%, a mean average precision of 98.4%, and an inference time of 2.0ms. Comparative tests reveal that VBGS-YOLOv8n strikes a balance between detection accuracy, speed, and model efficiency compared to YOLOv8 and other mainstream networks. Specifically, compared to YOLOv8, the model parameters and FLOPs are reduced by 51.7% and 52.8% respectively, while precision and a mean average precision are improved by 1.4% and 0.8% respectively, and the inference time is reduced by 31.0%. Discussion: Comparative tests with mainstream models, including YOLOv7, YOLOv5, RetinaNet, and QueryDet, demonstrate that VBGS-YOLOv8n outperforms these models in terms of detection accuracy, speed, and efficiency. The research highlights the effectiveness of VBGS-YOLOv8n in the efficient detection of potato seedlings in drone remote sensing images, providing a valuable reference for subsequent identification and deployment on mobile devices.

Extraction, characterization and intestinal anti-inflammatory and anti-oxidative activities of polysaccharide from stems and leaves of Chuanminshen violaceum M. L. Sheh & R. H. Shan.

ETHNOPHARMACOLOGICAL RELEVANCE: Chuanminshen violaceum M. L. Sheh & R. H. Shan (CV) is used as a medicine with roots, which have the effects of benefiting the lungs, harmonizing the stomach, resolving phlegm and detoxifying. Polysaccharide is one of its main active components and has various pharmacological activities, but the structural characterization and pharmacological activities of polysaccharide from the stems and leaves parts of CV are still unclear. AIM OF THE STUDY: The aim of this study was to investigate the optimal extraction conditions for ultrasound-assisted extraction of polysaccharide from CV stems and leaves, and to carry out preliminary structural analyses, anti-inflammatory and antioxidant effects of the obtained polysaccharide and to elucidate the underlying mechanisms. MATERIALS AND METHODS: The ultrasonic-assisted extraction of CV stems and leaves polysaccharides was carried out, and the response surface methodology (RSM) was used to optimize the extraction process to obtain CV polysaccharides (CVP) under the optimal conditions. Subsequently, we isolated and purified CVP to obtain the homogeneous polysaccharide CVP-AP-I, and evaluated the composition, molecular weight, and structural features of CVP-AP-I using a variety of technical methods. Finally, we tested the pharmacological activity of CVP-AP-Ⅰ in an LPS-induced model of oxidative stress and inflammation in intestinal porcine epithelial cells (IPEC-J2) and explored its possible mechanism of action. RESULTS: The crude polysaccharide was obtained under optimal extraction conditions and subsequently isolated and purified to obtain CVP-AP-Ⅰ (35.34 kDa), and the structural characterization indicated that CVP-AP-Ⅰ was mainly composed of galactose, galactose, rhamnose and glucose, which was a typical pectic polysaccharide. In addition, CVP-AP-Ⅰ attenuates LPS-induced inflammation and oxidative stress by inhibiting the expression of pro-inflammatory factor genes and proteins and up-regulating the expression of antioxidant enzyme-related genes and proteins in IPEC-J2, by a mechanism related to the activation of the Nrf2/Keap1 signaling pathway. CONCLUSION: The results of this study suggest that the polysaccharide isolated from CV stems and leaves was a pectic polysaccharide with similar pharmacological activities as CV roots, exhibiting strong anti-inflammatory and antioxidant activities, suggesting that CV stems and leaves could possess the same traditional efficacy as CV roots, which is expected to be used in the treatment of intestinal diseases.

Zearalenone Decreases Food Intake by Disrupting the Gut-Liver-Hypothalamus Axis Signaling via Bile Acids.

Zearalenone (ZEN) is a mycotoxin that is harmful to humans and animals. In this study, female and male rats were exposed to ZEN, and the results showed that ZEN reduced the farnesoid X receptor (FXR) expression levels in the liver and disrupted the enterohepatic circulation of bile acids (BAs). A decrease in food intake induced by ZEN was negatively correlated with an increase in the level of total BAs. BA-targeted metabolomics revealed that ZEN increased glycochenodeoxycholic acid levels and decreased the ratio of conjugated BAs to unconjugated BAs, which further increased the hypothalamic FXR expression levels. Preventing the increase in total BA levels induced by ZEN via Lactobacillus rhamnosus GG intervention restored the appetite. In conclusion, ZEN disrupted the enterohepatic circulation of BAs to decrease the level of food intake. This study reveals a possible mechanism by which ZEN affects food intake and provides a new approach to decrease the toxic effects of ZEN.

Standardized ileal digestibility of amino acids in Chinese fermented soybean meal from different sources fed to mid and late-gestating sows.

We determined apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of crude protein (CP) and amino acids (AA) in fermented soybean meal from five different sources (FSBM 1 to 5) in China when fed to mid and late-gestating sows. Twenty-four parity four sows (12 at 30 d in gestation and 12 at 80 d in gestation) were fitted with a T-cannula in the distal ileum and used in this experiment. Sows were randomly assigned to a replicated 6 × 3 Youden square design including six diets and three periods. Six diets were provided for sows in mid and late gestation, including a nitrogen-free diet and five test diets containing 26% FSBM from different sources. Results showed that there were differences in AID and SID of CP among the different FSBM samples, but no differences between sow physiological stages were observed. Specifically, when mid-gestating sows were fed FSBM 2, the AID of CP was the lowest, whereas FSBM 3 exhibited a greater AID of CP when compared to the other FSBM samples (P < 0.01). Furthermore, during late gestation, FSBM 3 consistently had greater SID of CP when compared to other FSBM samples (P < 0.01). The ileal digestibility of most AA varied with different FSBM samples. In both mid and late gestation, differences (P < 0.05) were observed for AID of lysine, tryptophan, histidine, and arginine across different FSBM samples. Similarly, the AID of dispensable AA (cysteine, glutamine, and serine) also exhibited differences (P < 0.05) across different FSBM samples in both mid and late-gestating sows. For mid-gestating sows, SID differences relating to lysine, phenylalanine, tryptophan, threonine, and arginine were observed among different diets (P < 0.05). In late-gestating sows, SID values for lysine, tryptophan, leucine, and arginine differed across diets (P < 0.05). Furthermore, the ileal digestibility of some dispensable AA was influenced by physiological stage, as evidenced by greater AID and SID values for glycine, glutamine, cysteine, and serine in late-gestating sows when compared to mid-gestating sows (P < 0.01). In summary, our study determined AA ileal digestibility of different FSBM fed to mid and late-gestating sows. We observed that the AA ileal digestibility differed among five FSBM samples, but the physiological stage of sows did not affect the ileal digestibility of CP and most AA. Additionally, when formulating diets for sows, it is crucial to consider the nutritional value differences of FSBM.

Fermented soybean meal (FSBM) is obtained from the microbial fermentation of soybean meal, which reduces anti-nutritional factor levels and enhances other nutrient content. Substituting soybean meal with FSBM in piglet and growing pig diets improves nutrient digestibility. However, its nutritional value for sows remains unclear. Therefore, five sources of FSBM were fed to sows in mid and late gestation to evaluate apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of amino acids (AA). We found that different FSBM samples impacted the SID value of AA when fed to gestating sows. Additionally, sow physiological stage influenced the SID of some dispensable AA. These findings provide valuable insights into the incorporation of FSBM into sow diets.

Bioactive α-Pyrone Analogs from the Endophytic Fungus Diaporthe sp. CB10100: α-Glucosidase Inhibitory Activity, Molecular Docking, and Molecular Dynamics Studies.

Two α-pyrone analogs were isolated from the endophytic fungus Diaporthe sp. CB10100, which is derived from the medicinal plant Sinomenium acutum. These analogs included a new compound, diaporpyrone F (3), and a known compound, diaporpyrone D (4). The structure of 3 was identified by a comprehensive examination of HRESIMS, 1D and 2D NMR spectroscopic data. Bioinformatics analysis revealed that biosynthetic gene clusters for α-pyrone analogs are common in fungi of Diaporthe species. The in vitro α-glucosidase inhibitory activity and antibacterial assay of 4 revealed that it has a 46.40% inhibitory effect on α-glucosidase at 800 µM, while no antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), Mycolicibacterium (Mycobacterium) smegmatis or Klebsiella pneumoniae at 64 µg/mL. Molecular docking and molecular dynamics simulations of 4 with α-glucosidase further suggested that the compounds are potential α-glucosidase inhibitors. Therefore, α-pyrone analogs can be used as lead compounds for α-glucosidase inhibitors in more in-depth studies.

Prediction of tumor origin in cancers of unknown primary origin with cytology-based deep learning.

Cancer of unknown primary (CUP) site poses diagnostic challenges due to its elusive nature. Many cases of CUP manifest as pleural and peritoneal serous effusions. Leveraging cytological images from 57,220 cases at four tertiary hospitals, we developed a deep-learning method for tumor origin differentiation using cytological histology (TORCH) that can identify malignancy and predict tumor origin in both hydrothorax and ascites. We examined its performance on three internal (n = 12,799) and two external (n = 14,538) testing sets. In both internal and external testing sets, TORCH achieved area under the receiver operating curve values ranging from 0.953 to 0.991 for cancer diagnosis and 0.953 to 0.979 for tumor origin localization. TORCH accurately predicted primary tumor origins, with a top-1 accuracy of 82.6% and top-3 accuracy of 98.9%. Compared with results derived from pathologists, TORCH showed better prediction efficacy (1.677 versus 1.265, P < 0.001), enhancing junior pathologists' diagnostic scores significantly (1.326 versus 1.101, P < 0.001). Patients with CUP whose initial treatment protocol was concordant with TORCH-predicted origins had better overall survival than those who were administrated discordant treatment (27 versus 17 months, P = 0.006). Our study underscores the potential of TORCH as a valuable ancillary tool in clinical practice, although further validation in randomized trials is warranted.

Association of dietary zinc consumption with periodontitis in diabetes mellitus patients: A cross-sectional study of national health and nutrition examination surveys database (2009-2014).

Background/purpose: Periodontitis is an independent risk factor for diabetes mellitus (DM), and DM patients had an increased risk in susceptibility to periodontitis. And serum zinc (Zn) levels were low in patients with periodontitis combined with DM. Herein, this study aimed to explore the association between dietary Zn intake and the risk of periodontitis in DM patients, in order to provide some scientific references for the prevention and treatment for periodontitis clinically. Materials and methods: Demographic and clinical data of DM patients were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2009-2014 in this cross-sectional study. Weighted univariate logistic regression and backward regression analyses were used for covariates screening. Weighted univariate and multivariate logistic regression analyses were used to explore the association between Zn and periodontitis with odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses of age and gender were also performed. Results: Of the eligible participants, 1281 had moderate or severe periodontitis. After adjusting for the covariates, we found that comparing to DM patients who had not reach the recommended Zn intake level, those who reached had low odds for periodontitis [OR = 0.76, 95% CI: (0.58-0.99)]. In patients who aged ≥65 years old [OR = 0.59, 95% CI: (0.36-0.97)] and were female [OR = 0.71, 95% CI: (0.51-0.99)], reaching the recommended level of Zn intake was related to low odds of periodontitis. Conclusion: Sufficient dietary Zn intake antagonized the risk of periodontitis, which may provide some references for diet management in DM patients to reduce the risk of periodontitis.

Survival and safety analysis of COVID-19 vaccine in Chinese patients with non-small cell lung cancer.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 disease (COVID-19) has caused a worldwide challenging and threatening pandemic. We aimed to assess the safety and efficacy of the COVID-19 vaccines in Non-Small Cell Lung Cancer (NSCLC) patients. METHODS: Patient self-reported adverse events related to vaccines were recorded by follow-up through a uniform questionnaire. Survival analysis was performed by Kaplan-Meier method. A multivariate analysis was performed by the Cox proportional hazard regression model to determine the effect of each variable on the survival of lung cancer patients. RESULTS: A total of 860 patients with NSCLC on treatment were enrolled. Mean age was 57 years in patients with early stage group and 62 years in advanced stage group. The vaccination rate was 71.11% for early-stage patients and 19.48% for advanced-stage patients; most of them (86.5%) received the COVID-19 inactivated virus (Vero cell) vaccine (Coronavac; Sinovac). The most common systemic adverse reaction was weakness. The main reason for vaccine refusal in those unvaccinated patients was concern about the safety of vaccination in the presence of a tumor and undergoing treatment (56.9% and 53.4%). The 1-year disease-free survival (DFS) rate was 100% for vaccinated and 97.4% for unvaccinated early-stage patients. Then we compared the progression-free survival (PFS) of vaccinated (median PFS 9.0 months) and unvaccinated (median PFS 7.0 months) advanced stage patients (p = 0.815). Advanced NSCLC patients continued to be divided into groups receiving radio-chemotherapy, immunotherapy, and targeted therapy, with no statistical difference in PFS between the groups (p > 0.05). The median overall survival (OS) of vaccinated patients was 20.5 months, and that of unvaccinated patients was 19.0 months (p = 0.478) in advanced NSCLC patients. CONCLUSIONS: COVID-19 vaccination is safe for Chinese NSCLC patients actively receiving different antitumor treatments without increasing the incidence of adverse reactions, and vaccination does not affect cancer patient survival.

Surgical treatment for pelvic haemophilic pseudotumour: a retrospective analysis of 21 cases.

Background: Due to the rarity of pelvic haemophilic pseudotumour (PHPT) and demanding surgical technique for PHPT excision, no study reports the mid-term follow-up outcomes of surgical treatment of PHPT in a relatively large cohort. PHPT with varying degrees of bony pelvic involvement and infection status necessitates different operative procedures, yet there is currently no classification system for PHPT based on surgical practice. Methods: The study was conducted between June 25, 2004 and July 18, 2023, in Peking Union Medical College Hospital and Nanfang Hospital in China. We performed a retrospective analysis involving 21 patients with 24 PHPTs with a mean follow-up period of 7.1 years. The demographic information, PHPT characteristics, surgical data, and perioperative complications were analysed. Findings: 21 consecutive male patients with 24 PHPTs (21 primary PHPTs and three recurrent PHPTs) that underwent surgical treatment were involved in the study. A classification system including four subtypes was introduced as (I) PHPT confined to soft tissue; (II) PHPT involving bony pelvic without pelvic discontinuity; (III) PHPT causing pelvic discontinuity; (IV) Infectious PHPT. Of the 24 PHPTs, 11 (45.8%) were identified as Type I, five (20.8%) as Type II, three (12.5%) as Type III, and five (20.8%) as Type IV. At the time of surgery, the patients had a mean age of 37.0 ± 9.5 years (Range, 24-52 years). The mean maximum diameter of PHPTs upon surgery was 17.0 ± 7.7 cm (Range, 4.3-40.0 cm). The mean surgical duration was 192 ± 77 min (Range, 60-330 min) and the median intraoperative blood loss was 400 mL (IQR, 225-950 mL, Range, 100-3000 mL). One patient (4.8%) underwent intraoperative cardiopulmonary arrest and expired the following week. Four PHPTs (16.7%) presented postoperative wound infections and poor wound healing. During the follow-up period, five PHPTs (20.8%) experienced pseudotumour recurrence. Interpretation: Our findings suggest that surgical treatment for PHPTs is feasible and relatively safe. Symptomatic and progressive PHPTs should undergo surgical intervention as early as possible to minimise the surgical risks. Intraoperative use of abundant gelatin sponges in PHPT excision draws attention to severe embolism complications. Funding: There are no sources of funding for this manuscript.

High-efficiency fourth harmonic generation and polarization smoothing based on an orthogonal cascade of DKDP crystals: publisher's note.

This publisher's note corrects an error in Appl. Opt.63, 1411 (2024)APOPAI0003-693510.1364/AO.512229.

High-efficiency fourth harmonic generation and polarization smoothing based on an orthogonal cascade of DKDP crystals.

Because of the high efficiency of frequency conversion and beam-target coupling, a fourth harmonic (4ω) laser has a splendid application prospect in a high-power laser facility. The polarization smoothing (PS) crystal is preferably after the frequency conversion crystal to flexibly obtain the best uniformity illumination of the target. However, as a high irradiance 4ω laser beam propagates through the PS crystal, the transverse stimulated Raman scattering (TSRS) effect of the PS crystal will be stronger, resulting in significant energy dissipation and crystal damage. This paper proposes a novel, to the best of our knowledge, fourth harmonic generation (FHG) scheme based on an orthogonal cascade of the DKDP crystals. This orthogonal cascaded FHG (OC-FHG) scheme employs two cascaded FHG crystals with orthogonal optical axes, and the PS crystal is in the middle. The PS crystal can rotate the polarization direction of the 2ω laser by 90°, while the polarization direction of the 4ω laser is maintained to a great extent. This OC-FHG scheme realizes the FHG by two steps, and the laser intensity at the PS crystal cuts down nearly 50%. The output intensity of the 4ω laser can be increased from 1.8G W/c m 2 to about 3.6G W/c m 2 under the condition of effectively inhibiting the TSRS effect. Meanwhile, the output 4ω laser contains two orthogonal polarized beams realizing in-beam polarization smoothing instantaneously. In addition, the novel FHG scheme can also have a high conversion efficiency and bandwidth tolerance.

Dictyophora indusiata and Bacillus aryabhattai improve sugarcane yield by endogenously associating with the root and regulating flavonoid metabolism.

Introduction: Endophytes play a significant role in regulating plant root development and facilitating nutrient solubilization and transportation. This association could improve plant growth. The present study has uncovered a distinct phenotype, which we refer to as "white root", arising from the intricate interactions between endophytic fungi and bacteria with the roots in a sugarcane and bamboo fungus (Dictyophora indusiata) intercropping system. Methods: We investigated the mechanisms underlying the formation of this "white root" phenotype and its impact on sugarcane yield and metabolism by metabarcoding and metabolome analysis. Results and Discussion: Initial analysis revealed that intercropping with D. indusiata increased sugarcane yield by enhancing the number of viable tillers compared with bagasse and no input control. Metabarcoding based on second-generation and third-generation sequencing indicated that D. indusiate and Bacillus aryabhattai dominates the fungal and bacterial composition in the "white root" phenotype of sugarcane root. The coexistence of D. indusiata and B. aryabhattai as endophytes induced plant growth-promoting metabolites in the sugarcane root system, such as lysoPC 18:1 and dihydrobenzofuran, probably contributing to increased sugarcane yield. Furthermore, the association also enhanced the metabolism of compounds, such as naringenin-7-O-glucoside (Prunin), naringenin-7-O-neohesperidoside (Naringin)*, hesperetin-7-O-neohesperidoside (Neohesperidin), epicatechin, and aromadendrin (Dihydrokaempferol), involved in flavonoid metabolism during the formation of the endophytic phenotype in the sugarcane root system. These observations suggest that the "white root" phenotype promotes sugarcane growth by activating flavonoid metabolism. This study reports an interesting phenomenon where D. indusiata, coordinate with the specific bacteria invade, forms a "white root" phenotype with sugarcane root. The study also provides new insights into using D. indusiata as a soil inoculant for promoting sugarcane growth and proposes a new approach for improve sugarcane cultivation.

Nanoscale Localized Phonons at Al2O3 Grain Boundaries.

Nanoscale defects like grain boundaries (GBs) would introduce local phonon modes and affect the bulk materials' thermal, electrical, optical, and mechanical properties. It is highly desirable to correlate the phonon modes and atomic arrangements for individual defects to precisely understand the structure-property relation. Here we investigated the localized phonon modes of Al2O3 GBs by combination of the vibrational electron energy loss spectroscopy (EELS) in scanning transmission electron microscope and density functional perturbation theory (DFPT). The differences between GB and bulk obtained from the vibrational EELS show that the GB exhibited more active vibration at the energy range of <50 meV and >80 meV, and further DFPT results proved the wide distribution of bond lengths at GB are the main factor for the emergence of local phonon modes. This research provides insights into the phonon-defect relation and would be of importance in the design and application of polycrystalline materials.