All-multimode fiber spatiotemporal mode-locked figure-eight laser based on multimode gain fiber.

In this paper, we report for the first time on an all-multimode fiber spatiotemporal mode-locked figure-eight laser operating at 1.0 µm. This laser utilizes a multimode gain fiber and a nonlinear amplifying loop mirror mechanism. It can generate mode-locked noise-like pulses at different central wavelengths. Additionally, we observed the presence of a multi-soliton state within the cavity by reducing intracavity gain. This study contributes to a broader investigation of various pulse phenomena in spatiotemporal mode-locked lasers and provides valuable insights into further exploring the evolution of spatiotemporal dynamics in such systems.

Decoding river pollution trends and their landscape determinants in an ecologically fragile karst basin using a machine learning model.

Karst watersheds accommodate high landscape complexity and are influenced by both human-induced and natural activity, which affects the formation and process of runoff, sediment connectivity and contaminant transport and alters natural hydrological and nutrient cycling. However, physical monitoring stations are costly and labor-intensive, which has confined the assessment of water quality impairments on spatial scale. The geographical characteristics of catchments are potential influencing factors of water quality, often overlooked in previous studies of highly heterogeneous karst landscape. To solve this problem, we developed a machining learning method and applied Extreme Gradient Boosting (XGBoost) to predict the spatial distribution of water quality in the world's most ecologically fragile karst watershed. We used the Shapley Addition interpretation (SHAP) to explain the potential determinants. Before this process, we first used the water quality damage index (WQI-DET) to evaluate the water quality impairment status and determined that CODMn, TN and TP were causing river water quality impairments in the WRB. Second, we selected 46 watershed features based on the three key processes (sources-mobilization-transport) which affect the temporal and spatial variation of river pollutants to predict water quality in unmonitored reaches and decipher the potential determinants of river impairments. The predicting range of CODMn spanned from 1.39 mg/L to 17.40 mg/L. The predictions of TP and TN ranged from 0.02 to 1.31 mg/L and 0.25-5.72 mg/L, respectively. In general, the XGBoost model performs well in predicting the concentration of water quality in the WRB. SHAP explained that pollutant levels may be driven by three factors: anthropogenic sources (agricultural pollution inputs), fragile soils (low organic carbon content and high soil permeability to water flow), and pollutant transport mechanisms (TWI, carbonate rocks). Our study provides key data to support decision-making for water quality restoration projects in the WRB and information to help bridge the science:policy gap.

The effect of inhibition of endoplasmic reticulum stress on lipolysis in white adipose tissue in a rat model of chronic kidney disease.

AIM: Lipolysis in fat tissue plays an important role in the development of metabolic disturbances, a characteristic feature of chronic kidney disease (CKD). In the present study, we tested the hypothesis that the inhibition of endoplasmic reticulum (ER) stress could alleviate lipolysis in white adipose tissue in a rat model of CKD. METHODS: A rat model of CKD was established by a method of reduced renal mass (RRM). Lipolysis was measured as the release of glycerol in ex vivo fat pads and cultured primary adipocytes. The activity of lipases and markers of ER stress were measured by Western blotting and immunoprecipitation. RESULTS: Our data showed that lipolysis in visceral white adipose tissue was increased in RRM rats compared with control rats. In addition, increased phosphorylation of hormone-sensitive lipase (HSL) and binding of adipose triglyceride lipase (ATGL) to comparative gene identification-58 (CGI-58) protein were observed in the RRM rats. The phosphorylation of ER stress markers, including IRE1α, PERK, and eukaryotic initiation factor (eIF) 2α, and the expression of ER stress marker 78 kDa glucose-regulated protein (GRP78) were significantly increased in RRM rats. Treatment with an inhibitor of ER stress partially but significantly alleviated lipolysis, and this alleviation was accompanied by reduced binding of ATGL to CGI-58. CONCLUSION: Our results showed that enhanced lipolysis and ER stress occurred in visceral white adipose tissue in a rat model of CKD. Moreover, inhibition of ER stress significantly alleviated lipolysis. These findings suggest that ER stress is a potential therapeutic target for the metabolic disturbances associated with CKD.

Safety and Efficacy of CT-Guided Central Venous Catheter Gastric Insufflation in Percutaneous Gastrostomy.

Gastric insufflation for computed tomography (CT)-guided percutaneous gastrostomy is currently performed via a nasogastric tube or a Chiba needle. However, nasogastric tube placement requires patient pharynx and esophagus, and Chiba needle use is associated with an increased risk of organ damage and prolonged operation time. Herein, we introduce a new method of gastric insufflation via a central venous catheter and explore its safety and efficacy by retrospective analysis of the clinical data of patients who underwent percutaneous gastrostomy using this method in our hospital from April 2021 to March 2022. The extracted data included the following: success rate, operation time, gastric insufflation time, radiation dose, postoperative pain score, and complications. We also compared the preoperative levels of several nutritional indicators (body mass index, hemoglobin, albumin, creatinine, and blood urea nitrogen) with those obtained 1 month postoperatively. A total of 12 patients underwent percutaneous gastrostomy under CT guidance using central venous catheter gastric insufflation. The surgery and gastric insufflation success rates were 100% both. The average operation time, gastric insufflation time, and effective radiation dose were 24.08 ± 5.25 min, 5.08 ± 2.50 min, and 14.16 ± 3.63 mSv, respectively. Based on the World Health Organization scale for pain assessment, five patients reported no postoperative pain and seven patients had mild pain. There were no serious complications, such as stoma infection, peritonitis, gastrointestinal perforation and bleeding, or embedding syndrome. All evaluated nutritional indicators showed improvement at 1 month postoperatively, with statistically significant differences compared to the preoperative values (p < 0.05 for all). In conclusion, CT-guided percutaneous gastrostomy with central venous catheter gastric insufflation is a safe, effective, and feasible minimally invasive treatment.