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The use of microscale heat generating or heat transfer equipment with higher capacity and smaller dimensions requires more accurate management and better disposal of their produced heat. This makes the necessity of designing and manufacturing superconductors completely clear. In the meantime, the nano-grooved flat plate heat pipes (FPHP) have gained the industry's attention. Due to the provision of the conditions for manufacturing devices on a micro scale, it is possible to integrate this type of heat pipe with other microscale devices. In the meantime, understanding their behavior on small scales requires more studies. In this paper, the effect of using barriers to improve the thermal performance of a nano FPHP (1050 × 220 × 95 Å) is evaluated. Simulations are performed on a molecular scale through molecular dynamics (MD) simulations using LAMMPS® software. Platinum (Pt), copper (Cu), and aluminum (Al) are used for HP's body. In addition, argon (Ar), water (H2O), and ethanol (EtOH) are used as working fluids. The results show that increasing the number of barriers leads to improved thermal performance. Different cases include different teeth called barriers augmented inside HP are simulated. The combination of Cu-EtOH showed the best thermal performance (about 18 % better than other cases). Cubical barriers have more heat flux improvement than conical ones (from 3.5 % up to about 10.7 %). Among the three fluids used, EtOH leads to a better heat flux (about 6 % for Pt and up to 15 % for Cu). Using 24 barriers, a very favorable result of 1992 W/cm2 heat flux is achieved. In this case, the minimum heat flux is obtained by using Pt and Ar and is 1609 W/cm2. Using Ar and the cub shape barriers, the highest mass transfer rates for Pt, Cu, and Al are about 35.2 %, 38.9 %, and 38 %, respectively.

Abstract Tumor organoids, especially patient-derived organoids (PDOs) exhibit marked similarities in histopathological morphology, genomic alterations, and specific marker expression profiles to those of primary tumour tissues. They are applied in various fields including drug screening, gene editing, and identification of oncogenes. However, CAR-T therapy in the treatment of solid tumours is still at an exploratory stage. Tumour organoids offer unique advantages over other preclinical models commonly used for CAR-T therapy research, which the preservation of the biological characteristics of primary tumour tissue is critical for the study of early-stage solid tumour CAR-T therapies. Although some investigators have used this co-culture model to validate newly targeted CAR-T cells, optimise existing CAR-T cells and explore combination therapy strategies, there is still untapped potential in the co-culture models used today. This review introduces the current status of the application of tumour organoid and CAR-T cell co-culture models in recent years and commented on the limitations of the current co-cultivation model. Meanwhile, we compared the tumour organoid model with two pre-clinical models commonly used in CAR-T therapy research. Eventually, combined with the new progress of organoid technologies, optimization suggestions were proposed for the co-culture model from five perspectives: preserving or reconstructing the tumor microenvironment, systematization, vascularization, standardized culture procedures, and expanding the tumor organoids resource library, aimed at assisting related researchers to better utilize co-culture models.

BackgroundFungal infections are associated with high morbidity and mortality in the intensive care unit (ICU), but their diagnosis is difficult. In this study, machine learning was applied to design and define the predictive model of ICU-acquired fungi (ICU-AF) in the early stage of fungal infections using Random Forest.ObjectivesThis study aimed to provide evidence for the early warning and management of fungal infections.MethodsWe analyzed the data of patients with culture-positive fungi during their admission to seven ICUs of the First Affiliated Hospital of Chongqing Medical University from January 1, 2015, to December 31, 2019. Patients whose first culture was positive for fungi longer than 48 h after ICU admission were included in the ICU-AF cohort. A predictive model of ICU-AF was obtained using the Least Absolute Shrinkage and Selection Operator and machine learning, and the relationship between the features within the model and the disease severity and mortality of patients was analyzed. Finally, the relationships between the ICU-AF model, antifungal therapy and empirical antifungal therapy were analyzed.ResultsA total of 1,434 cases were included finally. We used lasso dimensionality reduction for all features and selected six features with importance ≥0.05 in the optimal model, namely, times of arterial catheter, enteral nutrition, corticosteroids, broadspectrum antibiotics, urinary catheter, and invasive mechanical ventilation. The area under the curve of the model for predicting ICU-AF was 0.981 in the test set, with a sensitivity of 0.960 and specificity of 0.990. The times of arterial catheter (p = 0.011, OR = 1.057, 95% CI = 1.053–1.104) and invasive mechanical ventilation (p = 0.007, OR = 1.056, 95%CI = 1.015–1.098) were independent risk factors for antifungal therapy in ICU-AF. The times of arterial catheter (p = 0.004, OR = 1.098, 95%CI = 0.855–0.970) were an independent risk factor for empirical antifungal therapy.ConclusionThe most important risk factors for ICU-AF are the six time-related features of clinical parameters (arterial catheter, enteral nutrition, corticosteroids, broadspectrum antibiotics, urinary catheter, and invasive mechanical ventilation), which provide early warning for the occurrence of fungal infection. Furthermore, this model can help ICU physicians to assess whether empiric antifungal therapy should be administered to ICU patients who are susceptible to fungal infections.

The lake water surface temperature (LWST) is a critical parameter influencing lake ecosystem dynamics and addressing challenges posed by climate change. Traditional point measurement techniques exhibit limitations in providing comprehensive LWST data. However, the emergence of satellite remote sensing and unmanned aerial vehicle (UAV) Thermal Infrared (TIR) technology has opened new possibilities. This study presents an approach for retrieving plateau lake LWST (p-LWST) from UAV TIR data. The UAV TIR dataset, obtained from the DJI Zenmuse H20T sensor, was stitched together to form an image of brightness temperature (BT). Atmospheric parameters for atmospheric correction were acquired by combining the UAV dataset with the ERA5 reanalysis data and MODTRAN5.2. Lake Water Surface Emissivity (LWSE) spectral curves were derived using 102 hand-portable FT-IR spectrometer (102F) measurements, along with the sensor’s spectral response function, to obtain the corresponding LWSE. Using estimated atmospheric parameters, LWSE, and UAV BT, the un-calibrated LWST was calculated through the TIR radiative transfer model. To validate the LWST retrieval accuracy, the FLIR Infrared Thermal Imager T610 and the Fluke 51-II contact thermometer were utilized to estimate on-point LWST. This on-point data was employed for cross-calibration and verification. In the study area, the p-LWST method retrieved LWST ranging from 288 K to 295 K over Erhai Lake in the plateau region, with a final retrieval accuracy of 0.89 K. Results demonstrate that the proposed p-LWST method is effective for LWST retrieval, offering technical and theoretical support for monitoring climate change in plateau lakes.

BackgroundDieulafoy’s lesion is an uncommon cause of hemorrhage of the digestive tract. It often presents with urgent and massive bleeding usually leading to shock, even death. Dieulafoy’s lesions have been reported throughout the digestive tract but which occurred on duodenal papilla were particularly rare and presented challenges in the choice of hemostasis.Case presentationA 66-year-old man with melena for 2 days was admitted. Gastrointestinal endoscopy revealed blood clots covering the duodenal papilla with oozing blood. During the procedure of trying to place a plastic stent into the duodenal papilla first, the hemorrhage began to present pulsating bleeding. The patient went into shock. With consent, two titanium clips were inserted to clamp the bleeding site to stop the bleeding. The patient complained of epigastric pain 14 h after the endoscopy. An abdominal CT scan showed signs of acute pancreatitis. Endoscopy was performed to remove the titanium clips and showed a vessel stump on the duodenal papilla. The patient was discharged from the hospital on the 14th day and followed for 6 months with no recurrence.ConclusionThis case was diagnosed with a Dieulafoy’s lesion on the duodenal papilla, which has rarely been reported. Hematemesis was stopped by clamping the vessel stump with titanium clips but caused acute pancreatitis. Reviewing the treatment, electrocoagulation might be a better choice, and life support treatment, including central vena catheterization and an adequate supply of blood products, should be prepared in advance to provide extra time for the stent placement or vascular intervention treatment.

Abstract This letter proposes an interleaved hybrid control for parallel three‐level (TL) LLC converters in battery charging applications. The duty cycle and the switching frequency are used to adjust the voltage gain; the phase shift control is adopted to realize voltage sharing of the divided capacitors. A virtual equivalent frequency‐gain control is adopted to coordinate multiple control variables. And the current ripples are reduced for the interleaved structure. Based on the performance analysis, an upper optimizer is proposed to update the upper limit frequency and interleaving arrangement in real time. Accordingly, it achieves a wide range of output voltage, and it further improves the system efficiency under light load and low output voltage conditions. A prototype is presented to verify the effectiveness of the proposed method.