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Abstract Thermochromic hydrogels exhibit a smart capacity for regulating solar spectrum transmission, enabling automatically change their transmissivity in response to the ambient temperature change. This has great importance for energy conservation purposes. Military and civilian emergency thermochromic applications require rapid visible-light stealth (VLS); however, concurrent smart solar transmission and rapid VLS is yet to be realized. Inspired by squid-skin, we propose a micropatterned thermochromic hydrogel (MTH) to realize the concurrent control of smart solar transmittance and rapid VLS at all-working temperatures. The MTH possesses two optical regulation mechanisms: optical property regulation and optical scattering, controlled by temperature and pressure, respectively. The introduced surface micropattern strategy can arbitrarily switch between normal and diffuse transmission, and the VLS response time is within 1 s compared with previous ~180 s. The MTH also has a high solar-transmission regulation range of 61%. Further, the MTH preparation method is scalable and cost-effective. This novel regulation mechanism opens a new pathway towards applications with multifunctional optical requirements.

Abstract Background To date, carbohydrate antigen 19‐9 (CA19‐9) and carcinoembryonic antigen (CEA) have been widely used for the screening, diagnosis and prediction of biliary tract cancer (BTC) patients. However, few studies with large sample sizes of carbohydrate antigen 50 (CA50) were reported in BTC patients. Methods A total of 1121 patients from the Liver Cancer Clin‐Bio Databank of Anhui Hepatobiliary Surgery Union between January 2017 and December 2022 were included in this study (673 in the training cohort and 448 in the validation cohort): among them, 458 with BTC, 178 with hepatocellular carcinoma (HCC), 23 with combined hepatocellular‐cholangiocarcinoma, and 462 with nontumor patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the diagnostic efficacy and clinical usefulness. Results ROC curves obtained by combining CA50, CA19‐9, and AFP showed that the AUC value of the diagnostic MODEL 1 was 0.885 (95% CI 0.856–0.885, specificity 70.3%, and sensitivity 84.0%) in the training cohort and 0.879 (0.841–0.917, 76.7%, and 84.3%) in the validation cohort. In addition, comparing iCCA and HCC (235 in the training cohort, 157 in the validation cohort), the AUC values of the diagnostic MODEL 2 were 0.893 (95% CI 0.853–0.933, specificity 96%, and sensitivity 68.6%) in the training cohort and 0.872 (95% CI 0.818–0.927, 94.2%, and 64.6%) in the validation cohort. Conclusion The model combining CA50, CA19‐9, and AFP not only has good diagnostic value for BTC but also has good diagnostic value for distinguishing iCCA and HCC.

BackgroundOur study aimed to develop a nomogram incorporating cytokeratin fragment antigen 21–1 (CYFRA21–1) to assist in differentiating between patients with intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC).MethodsA total of 487 patients who were diagnosed with ICC and HCC at Qilu Hospital of Shandong University were included in this study. The patients were divided into a training cohort and a validation cohort based on whether the data collection was retrospective or prospective. Univariate and multivariate analyses were employed to select variables for the nomogram. The discrimination and calibration of the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC) and calibration plots. Decision curve analysis (DCA) was used to assess the nomogram’s net benefits at various threshold probabilities.ResultsSix variables, including CYFRA21–1, were incorporated to establish the nomogram. Its satisfactory discriminative ability was indicated by the AUC (0.972 for the training cohort, 0.994 for the validation cohort), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) values. The Hosmer–Lemeshow test and the calibration plots demonstrated favorable consistency between the nomogram predictions and the actual observations. Moreover, DCA revealed the clinical utility and superior discriminative ability of the nomogram compared to the model without CYFRA21–1 and the model consisting of the logarithm of alpha-fetoprotein (Log AFP) and the logarithm of carbohydrate antigen 19–9 (Log CA19–9). Additionally, the AUC values suggested that the discriminative ability of Log CYFRA21–1 was greater than that of the other variables used as diagnostic biomarkers.ConclusionsThis study developed and validated a nomogram including CYFRA21–1, which can aid clinicians in the differential diagnosis of ICC and HCC patients.

Abstract The radar and infrared (IR) compatible stealth technology is an important technology in the military field. Inspired by the special triangular‐shaped hairs from the Saharan silver ants, a bionic structure with IR wavelength‐selective emission and large microwave transmission simultaneously is presented. An algorithm based on the combination of Bayesian optimization and finite different time domain method is proposed for optimal design. The proposed structure is an indium tin oxide (ITO)‐hairs/ITO‐film/PET‐substrate structure. The IR wavelength‐selectivity is reached by the hair covered ITO film, and the microwave transmission is realized by patterning gap arrays on continuous films. After optimal calculation, the optimal bionic structure is obtained. The change of the structural parameters of the meta‐atom will lead to a change in microwave transmission. When p = 0.1 mm and w = 0.9 mm, the maximum and minimum transmittivity of the infrared stealth layer (IRSL) in 2–20 GHz are 0.972 and 0.764, respectively, while the estimated emissivity in 3–5, 5–8, and 8–14 µm wavebands are 0.592, 0.730, and 0.373, respectively. It illustrates that the IRSL maintains IR wavelength‐selective emission while maintaining high microwave transmission. This study provides a strategy for bionic structure applied in compatible stealth.

The burning of fossil fuels in industry results in significant carbon emissions, and the heat generated is often not fully utilized. For high-temperature industries, thermophotovoltaics (TPVs) is an effective method for waste heat recovery. This review covers two aspects of high-efficiency TPV systems and industrial waste heat applications. At the system level, representative results of TPV complete the systems, while selective emitters and photovoltaic cells in the last decade are compiled. The key points of components to improve the energy conversion efficiency are further analyzed, and the related micro/nano-fabrication methods are introduced. At the application level, the feasibility of TPV applications in high-temperature industries is shown from the world waste heat utilization situation. The potential of TPV in waste heat recovery and carbon neutrality is illustrated with the steel industry as an example.

ObjectiveNon-invasive methods for hemoglobin (Hb) monitoring can provide additional and relatively precise information between invasive measurements of Hb to help doctors' decision-making. We aimed to develop a new method for Hb monitoring based on mask R-CNN and MobileNetV3 with eye images as input.MethodsSurgical patients from our center were enrolled. After image acquisition and pre-processing, the eye images, the manually selected palpebral conjunctiva, and features extracted, respectively, from the two kinds of images were used as inputs. A combination of feature engineering and regression, solely MobileNetV3, and a combination of mask R-CNN and MobileNetV3 were applied for model development. The model's performance was evaluated using metrics such as R2, explained variance score (EVS), and mean absolute error (MAE).ResultsA total of 1,065 original images were analyzed. The model's performance based on the combination of mask R-CNN and MobileNetV3 using the eye images achieved an R2, EVS, and MAE of 0.503 (95% CI, 0.499–0.507), 0.518 (95% CI, 0.515–0.522) and 1.6 g/dL (95% CI, 1.6–1.6 g/dL), which was similar to that based on MobileNetV3 using the manually selected palpebral conjunctiva images (R2: 0.509, EVS:0.516, MAE:1.6 g/dL).ConclusionWe developed a new and automatic method for Hb monitoring to help medical staffs' decision-making with high efficiency, especially in cases of disaster rescue, casualty transport, and so on.

Objective: Meets the requirements of no overshoot in the response of the liquor blending control system, and eliminate the influence of system time lag on its control effect. Methods: An algorithm of liquor blending control based on variable universe fuzzy-Smith was proposed. Analyzed the control process and characteristics of the system and establish an approximate mathematical model. Quoting Smith predictor to compensate for the time lag in the system, utilizing the characteristics of fuzzy control to solve the problem of inaccurate system mathematics model, combined with the variable universe method to eliminate the shortcomings of conventional fuzzy control method with steady-state errors due to the poor accuracy. The algorithm was simulated by Matlab. Results: Compared with PID-Smith and fuzzy-Smith control algorithm, on the premise of ensuring that there was no overshoot in the system response, and the proposed algorithm had faster adjustment speed and better robustness. Conclusion: The variable universe fuzzy-Smith algorithm can realize the precise control of the flow of the liquor blending control system.

Flash evaporation processes are widely used in petroleum, food, chemical, power, and other industries to separate products or extract heat. The liquid is often entrained by non-condensing gas components. This study develops a multiphase, multicomponent, and pressure-driven phase-change-coupled model to numerically study water flash evaporation with non-condensing CO2. The model includes the mass, momentum, energy, volume of fluid (VOF), species transport, turbulence (RNG k-ε), modified phase-change Lee, and non-condensing CO2 release governing equations. The steam generation rate and mechanism for pure water and different concentrations of CO2 are considered. The results show that the numerical model can accurately predict the flash evaporation process and has high accuracy compared with the experimental data. Both the dissolved and entrained CO2 that are released can severely disturb the flow field, leading to an increase in the steam generation rate. Under a 1–10% volume concentration of dissolved CO2 and 0.0661–0.1688% mass concentration of entrained CO2, the maximum increase ratio of steam generation can reach 20%.

Finite-time leader-following consensus problem of second-order multi-agent system (MAS) with nonlinear dynamics under directed communication topology is investigated in this paper. Based on the event triggered mechanism, a novel finite-time integral sliding mode control strategy is proposed to guarantee that the consensus stability of MAS can be reached within the upper limit of the time, which can be predicted according to the initial state of MAS. The event-triggered condition on the basis of the defined novel measurement error effectively reduces the energy dissipation of the system and the update frequency of the controller, and the deduced lower bound expression of the event-triggered time interval avoids the occurrence of zeno behavior. Numerical simulation results illustrate the effectiveness and feasibility of the proposed algorithm.

Understanding the hydrogen (H) capacity, which represents the tritium capacity in Li2TiO3 crystal has become an important aspect of the tritium release process of nuclear fusion. In this work, a systematic density-functional-theory (DFT) study is performed to investigate the trapping and accumulation of H in Li2TiO3 crystal. In perfect crystal, the H adsorption properties are investigated and the maximum number of trapped H atoms are obtained. In the defect models, by calculating the trapping energy and Bader charge, we find that a Li vacancy can capture four H atoms while the capacity of a Ti vacancy is seven and then other H atoms tend to be trapped by interstitial sites outside the vacancy. Then the H capacity both inside and outside the vacancy in the defect models is studied and analyzed. According to our calculations, crystals containing a vacancy present stronger H trapping abilities than perfect crystals, especially for the crystal with a Ti vacancy. In addition, the increase of H atoms in the vacancy facilitates the formation of the neighboring vacancy so that more H atoms can be accommodated in the crystal with vacancy. Our results reveal the H capacity of different Li2TiO3 models, which provide theoretical support for related tritium release experiments. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the clinical efficacy of avatrombopag, an oral thrombopoietin receptor agonist, versus subcutaneous recombinant human thrombopoietin (rh-TPO) in the treatment of severe thrombocytopenia (TCP) associated with chronic liver disease (CLD).Methods: Clinical data of 250 patients with severe TCP associated with CLD were collected in a single hospital from January 2019 to January 2022. The main parameters measured were the therapeutic response rate, changes in platelets (PLTs), and adverse events. Propensity score matching (PSM) was used to avoid possible selection bias.Results: After PSM, a total of 154 patients were enrolled in the study: 77 in the avatrombopag group and 77 in the rh-TPO group. There was no statistically significant difference between the two groups in the effect of increasing the PLT count (Waldχ2 = 1.659, p = 0.198; Waldχ2 = 0.220, p = 0.639). In addition, no interaction between time and different medications was found (Waldχ2 = 0.540, p = 0.910; Waldχ2 = 1.273, p = 0.736). Interestingly, in the subgroup analysis, both before and after PSM, avatrombopag showed better clinical efficacy than rh-TPO in the treatment of TCP associated with CLD in Child‒Pugh Class A (88.89% vs. 63.41%, p =0.003; 81.33% vs. 61.76%, p = 0.043). Fewer patients reported dizziness in the avatrombopag group than in the rh-TPO group both before and after PSM (7.8% vs. 25.0%; 7.8% vs. 24.7%, p < 0.05).Conclusion: Both before and after PSM, avatrombopag showed better clinical efficacy than rh-TPO in the treatment of TCP associated with CLD in Child‒Pugh Class A and showed a lower incidence of dizziness in all patients.

In measuring the flame temperature and radiative properties, the light field camera is subject to the visible bands of the spectral snapshot measurement in a single shot. In this paper, the infrared light field camera is proposed to improve the spectral range of detection. The effects of the participating media on the infrared light field imaging are clarified. The temperature detection ranges of visible, near-infrared, and mid-infrared spectral bands are analyzed. The coupling effects of radiative properties of gas and soot on the mid-infrared light field imaging are compared. The light field imaging results show that the temperature detection range in the mid-infrared band is twice as much as that in the visible band. The gas and soot radiative properties have recognizable effects on the mid-infrared light field images. The absorption coefficient takes the primary role, while the scattering effects by 0.275. The mid-infrared light field camera is used to take snapshots of the flame. The temperature detection range is wider than the visible band, the gas and soot laden changes the flame structure. This work can be used as theoretical support for the design and application of infrared light field camera to diagnose the flame temperature and radiation properties.

Spray cooling has been considered one of the most promising thermal control methods of high-heat flux devices. Most of the spray cooling research focuses on electronic components as the main application object to achieve higher heat dissipation heat flow in ambient temperature regions for small areas. Water is the most common cooling medium. This paper investigates the application of spray cooling thermal control over large areas. In this study, the heat-transfer characteristics of liquid nitrogen (LN2) for large areas was investigated by conducting experiments. The test surface is 500 mm × 500 mm, which was cooled by a nine-nozzle array. The spray nozzles used in the experiment were conical nozzles with an orifice diameter of 1.6 mm, a spray angle of 120°, and a spray height of 42 mm. Liquid nitrogen was forcefully ejected from nozzles by the high pressure of a liquid storage tank to cool the test surface. According to the cooled surfaces, spray directions, and spray pressures, three groups of experiments were conducted. The results showed that the smooth flat surface has the best heat-transfer performance in three kinds of surface structures, which are macro surface, porous surface, and smooth flat surface. The heat-transfer coefficient varied by ±20% with different spray directions, and the surface heat-transfer coefficient increased linearly with increasing spray pressure. Most of the spray cooling research focuses on heat dissipation in the ambient temperature region for equipment over small areas. The results can benefit thermal control application in various fields. The research in this paper can provide a reference for the application of large-area spray cooling, and the application areas mainly include metal manufacturing processing cooling, aircraft skin infrared radiation characteristics modulation, and laser weapon equipment cooling.

Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes. During the casting filling process, many filling-related defects form easily at the confluences of liquid metal streams. The main filling-related defects are cold shut defects. To calculate the positions of casting defects, the characteristics of liquid metal confluences were analyzed. The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field, which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams. To distinguish small confluences from the main confluences, the concept of confluent scale was developed, which was used to filter the small confluences based on a threshold. The calculation process was demonstrated through the post-processing of numerical simulation. A “W” shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study. The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams. The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting. The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan.

Background: To date, carbohydrate antigen 19‐9 (CA19‐9) and carcinoembryonic antigen (CEA) have been widely used for the screening, diagnosis and prediction of biliary tract cancer (BTC) patients. However, few studies with large sample sizes of carbohydrate antigen 50 (CA50) were reported in BTC patients. Methods: A total of 1121 patients from the Liver Cancer Clin‐Bio Databank of Anhui Hepatobiliary Surgery Union between January 2017 and December 2022 were included in this study (673 in the training cohort and 448 in the validation cohort): among them, 458 with BTC, 178 with hepatocellular carcinoma (HCC), 23 with combined hepatocellular‐cholangiocarcinoma, and 462 with nontumor patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the diagnostic efficacy and clinical usefulness. Results: ROC curves obtained by combining CA50, CA19‐9, and AFP showed that the AUC value of the diagnostic MODEL 1 was 0.885 (95% CI 0.856–0.885, specificity 70.3%, and sensitivity 84.0%) in the training cohort and 0.879 (0.841–0.917, 76.7%, and 84.3%) in the validation cohort. In addition, comparing iCCA and HCC (235 in the training cohort, 157 in the validation cohort), the AUC values of the diagnostic MODEL 2 were 0.893 (95% CI 0.853–0.933, specificity 96%, and sensitivity 68.6%) in the training cohort and 0.872 (95% CI 0.818–0.927, 94.2%, and 64.6%) in the validation cohort. Conclusion: The model combining CA50, CA19‐9, and AFP not only has good diagnostic value for BTC but also has good diagnostic value for distinguishing iCCA and HCC. [ABSTRACT FROM AUTHOR]

Based on the solidification heat transfer model and the CAFE model, the solidification behavior and structure of 2311 die steel, with a cross-section dimension of 415 × 2270 mm at different casting speeds, specific water flow and superheat, is numerically simulated. Nail-shooting and acid-etching experiments are carried out on the slab to verify the model’s macroscopic size. With the increase in casting speed, the slab’s central equiaxed grain ratio (ECR) decreases and the average grain size increases. The increase in superheat promotes the growth of columnar grains and inhibits the growth of central equiaxed grains. When the superheat increases from 23 to 38 K, the ECR decreases from 43.2 to 29.64%, and the average radius of grains increases from 0.89 to 1.01 mm. With the increase in specific water flow, the ECR decreases, and the average grain radius is the smallest when the specific water content is 0.32 L kg−1. Finally, the slab quality is improved by process optimization, and the central segregation index of carbon decreases from mean value of 1.15 to 1.05.

Spray cooling has demonstrated advantages in the thermal control of avionic devices. In this study, a spray cooling system is established using liquid nitrogen (LN2) as a working fluid to investigate the effect of heat transfer characteristics on a large heating surface. The temperature response measurement and experimental analysis of the heating surface of a large-area shell structure under the boundary conditions of different heat flux and temperature regions were carried out. The temperature response curves for the outer surface of the shell structure from the initial temperature to the set temperature were obtained under different heat flows and temperature zones. The results show that the thermal response time of the surface spray phase cooling is less than 2 s, the stability time for the cooling temperature of the covering layer is longer than 60 s, and the cooling state can be maintained for 30 min under different working conditions. This study can provide a technical reference for the application of spray systems in the field of aircraft cooling.

The obtainment of spectral radiation characteristics of semitransparent materials mainly includes the use of a theoretical method or experimental method. As the experimental method can better characterize the real radiation transmission results inside the material, it is generally considered more reliable and used as the basis for the verification of theoretical results. In this paper, the absorbing and scattering semitransparent materials are taken as the analysis object to illustrate the research status and future development direction in the field of measurement and identification of spectral radiation characteristics. According to the physical quantities measured and the temperature range, research status is discussed for the spectral radiation characteristic measurements of absorbing and scattering semitransparent materials, which specifically involves the measurement principle, measuring system, measuring physical quantity, identification model and application range. This research will have guiding significance for the following research directions in the field of the acquisition of spectral radiation characteristic parameters of other new materials in the future.

In this study, the effects of the maldistribution coefficient on the thermo-hydraulic performance of discontinuous fin printed circuit heat exchanger (DF-PCHE) entrance head and channels are numerically investigated. To improve the flow uniformity at the entrance head, the flow in the exchanger with three types of spoiler perforated boards (SPBs) having 3 × 3, 4 × 4, and 5 × 5 holes and three kinds of hole diameters (Φd = 30, 25, and 20 mm), respectively, are compared to the flow in an exchanger with no SPB. The results show that a small maldistribution coefficient for the inlet velocity field is beneficial for the thermo-hydraulic performance of the DF-PCHE channels, and a maldistribution coefficient of 0.7 is an acceptable velocity distribution for the PCHE channel inlet. Using the 3 × 3 SPB with Φd = 30 mm, the maldistribution coefficient becomes 0.7, the fastest among all the SPB application cases at ΔL = 150 mm. Moreover, its heat transfer coefficient and pressure drop increase by 22.46% and decreases by 47.2% compared to those of the exchanger without SPB, respectively.