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Real-time stress sensing based on mechanoluminescence materials has been widely studied for structural health monitoring of bridges, buildings, high-pressure vessels, and other infrastructure surfaces. However, this approach is difficult to detect the stress information of closed mechanical structures. Here, we propose a delayed stress memory strategy to record the stress information of closed mechanical structure by the flexible film composed with CaAl2O4:Eu2+,Sm3+ phosphor. After the force is applied, the optical information on the film can be read out by the near-infrared laser after a period of time without real-time monitoring, and the stress distribution information of bearings and gears in the engine can be obtained. Furthermore, the regulation of trap depth from 0.662 to 1.042 eV allows the captured carriers to remain in the traps for a long time without being released as long persistent luminescence, which is beneficial to the delayed stress memory. Therefore, this work promotes the application prospect of mechanoluminescence materials in stress sensing, and provides a new idea to record the stress information of closed mechanical structures.

Heritage crimes can result in the significant loss of cultural relics and predicting them is crucial. To address the issues of inconsistent textual information format and the challenge of preventing and combating heritage crimes, this paper develops a system that extracts crime elements and predict heritage crime occurrences. The system comprises two deep-learning models. The first model, Bi-LSTM + CRF, is constructed to automatically extract crime elements and perform spatio-temporal analysis of crimes based on them. By integrating routine activity theory, social disorder theory, and practical field experience, the research reveals that holidays and other special days (SD) perform a critical role as influential factors in heritage crimes. Building upon these findings, the second model, LSTM + SD, is constructed to predict excavation-type heritage crimes. The results demonstrate that the model with the introduction of the holiday factor improves the RMSE and MAE by 6.4% and 47.8%, respectively, when compared to the original LSTM model. This paper presents research aimed at extracting crime elements and predicting excavation-type heritage crimes. With the ongoing expansion of data volume, the practical significance of the proposed system is poised to escalate. The results of this study are expected to provide decision-making support for heritage protection departments and public security authorities in preventing and combating crimes.

Due to the implementation of the climate change agreement, negative environmental impacts caused by some traditional refrigerants have been spotlighted. A large number of environmental- friendly refrigerants with near-zero ozone depleting potential (ODP) and low global warming potential (GWP), such as R1234yf, R1233zd(E), R1270, R600a, are synthesized and proposed to replace traditional ones. These refrigerants' boiling heat transfer characteristic plays a crucial role in evaporator design and refrigeration cycle configuration. Thus, this review aimed to bring the state-of-the-art literature review on the boiling heat transfer characteristics of environmental-friendly refrigerants with ODP close to 0 and GWP below 2000. In addition to describing the effects of heat flux, mass flow, saturation temperature, and mass transfer resistance on the heat transfer coefficient and pressure drop, this review also analyzed the heat transfer mechanism. Moreover, a detailed review of the correlation of boiling heat transfer and pressure drop was provided which might benefit practical applications. Furthermore, prospects and challenges to be addressed were also identified for future research. This paper benchmarks the recent progress on boiling heat transfer characteristics of single and mixed environmental-friendly refrigerants and presents insights into scientific research gaps that need to be addressed.

A phosphor has a red LPL at 250 K. The photoluminescence is white at a low temperature (4–84 K) and gradually turns red as the temperature increases. The blue luminescence of the matrix is quenched during the increase in temperature.

Proper defect states are demonstrated to be beneficial to overcome thermal quenching of the corresponding phosphors. In this work, a cyan-emitting KGaGeO

Background. This work used bioinformatic analysis to identify the relationship between periodontitis (PD) and aging, which could lead to new treatments for periodontal disease in the elderly. Method. Four microarray datasets were obtained from the Gene Expression Omnibus (GEO) database and analyzed in R language to identify differentially expressed genes (DEGs). The common DEGs of PD and aging were evaluated as key genes in this investigation by a Venn diagram. These common DEGs were analyzed through additional experiments and analysis, such as pathway analysis and enrichment analysis, and a network of protein-protein interactions (PPIs) was constructed. Cytoscape was used to visualize hub genes and critical modules based on the PPI network. Interaction of TF-genes and miRNAs with hub genes is identified. Result. 84 common DEGs were found between PD and aging. Cytohubba was performed on the PPI network obtained from STRING tool, and the top 10 genes (MMP2, PDGFRB, CTGF, CD34, CXCL12, VIM, IL2RG, ACTA2, COL4A2, and TAGLN) were selected as hub genes. VIM may be a potential biomarker in the analysis of linked hub gene regulatory networks, and hsa-mir-21 and hsa-mir-125b are predicted to be associated in PD and aging. Conclusion. This study investigated the key genes and pathways interactions between PD and aging, which may help reveal the correlation between PD and aging. The current research results are obtained by prediction, and follow-up biological experiments are required for further verification.

Organic room-temperature long-persistent luminescent materials are promising light-emitting materials for encryption, architectural decoration, organic solar cells, and biomedical applications. However, their unstable structures and thermal- and humidity-induced emission quenching have greatly limited their utility and reliability. Here, we report a metal-free nonconjugated copolymer that possesses stable photoluminescence at both high temperature and humidity. The room-temperature long-persistent luminescence (LPL) of this copolymer lasts for more than 15 s and can be recovered in high humidity conditions by heating to remove moisture. Copolymer LPL can be achieved with various excitation wavelengths, ranging from ultraviolet to near-infrared, and the LPL color can be adjusted accordingly. The high initial LPL intensity and ultrafast filling time of the copolymer makes it suitable for low flicker alternating current-driven light-emitting diodes (AC-LEDs).

We see the world with two eyes. Binocular vision provides more ample information through interocular interaction. Previous studies have shown that aging impairs a variety of visual functions, but how aging affects binocular vision is still unclear. In this study, we measured three typical binocular functions-binocular combination, binocular rivalry, and stereo vision-to investigate aging-related effects on binocular vision in a relatively large sample (48 younger adults and 27 older adults) with normal or corrected-to-normal distance vision and no ophthalmological and mental diseases. We found that there were no consistent aging-related declines in binocular vision, with the worst effect on alternation frequency in binocular rivalry and no effect on binocular phase combination and stereo vision tested by Titmus. In addition, aging changed the correlation pattern among some of these binocular functions. These results reflected (at least partially) different aging-related mechanism(s) in binocular vision.

To study the impact of manufacturer information referral on the decision-making of supply chain members, a Stackelberg model is constructed based on a manufacturer, a professional retailer and a store brand retailer. The optimal price and profit of the manufacturer and both retailers when manufacturer refers consumers to the professional retailer or not are solved and compared. Besides, the effect of the manufacturer’s information referral on the members of the supply chain is analyzed. The results show that the referral of manufacturer benefits both manufacturer and the referred retailer if the referral level meets certain conditions, otherwise it may reduce the profit of both parties, and the referral level is affected by the market size of the professional retailer. Meanwhile, under the influence of the professional retailer’s market size and the intensity of market competition, the store brand retailer will continue to operate only when the referral level stays in a certain range, but the profit of its store brand is damaged. However, if the referral level exceeds a certain threshold, the store brand product’s profit will increase with free riding.

Retinal segmentation is a prerequisite for quantifying retinal structural features and diagnosing related ophthalmic diseases. Canny operator is recognized as the best boundary detection operator so far, and is often used to obtain the initial boundary of the retina in retinal segmentation. However, the traditional Canny operator is susceptible to vascular shadows, vitreous artifacts, or noise interference in retinal segmentation, causing serious misdetection or missed detection. This paper proposed an improved Canny operator for automatic segmentation of retinal boundaries. The improved algorithm solves the problems of the traditional Canny operator by adding a multi-point boundary search step on the basis of the original method, and adjusts the convolution kernel. The algorithm was used to segment the retinal images of healthy subjects and age-related macular degeneration (AMD) patients; eleven retinal boundaries were identified and compared with the results of manual segmentation by the ophthalmologists. The average difference between the automatic and manual methods is: 2-6 microns (1~2 pixels) for healthy subjects and 3-10 microns (1~3 pixels) for AMD patients. Qualitative method is also used to verify the accuracy and stability of the algorithm. The percentage of “perfect segmentation” and “good segmentation” is 98% in healthy subjects and 94% in AMD patients. This algorithm can be used alone or in combination with other methods as an initial boundary detection algorithm. It is easy to understand and improve, and may become a useful tool for analyzing and diagnosing eye diseases.

The size and shape of the foveal avascular zone (FAZ) have a strong positive correlation with several vision-threatening retinovascular diseases. The identification, segmentation and analysis of FAZ are of great significance to clinical diagnosis and treatment. We presented an adaptive watershed algorithm to automatically extract FAZ from retinal optical coherence tomography angiography (OCTA) images. For the traditional watershed algorithm, “over-segmentation” is the most common problem. FAZ is often incorrectly divided into multiple regions by redundant “dams”. This paper analyzed the relationship between the “dams” length and the maximum inscribed circle radius of FAZ, and proposed an adaptive watershed algorithm to solve the problem of “over-segmentation”. Here, 132 healthy retinal images and 50 diabetic retinopathy (DR) images were used to verify the accuracy and stability of the algorithm. Three ophthalmologists were invited to make quantitative and qualitative evaluations on the segmentation results of this algorithm. The quantitative evaluation results show that the correlation coefficients between the automatic and manual segmentation results are 0.945 (in healthy subjects) and 0.927 (in DR patients), respectively. For qualitative evaluation, the percentages of “perfect segmentation” (score of 3) and “good segmentation” (score of 2) are 99.4% (in healthy subjects) and 98.7% (in DR patients), respectively. This work promotes the application of watershed algorithm in FAZ segmentation, making it a useful tool for analyzing and diagnosing eye diseases.

Regarding the control strategy of the permanent magnet synchronous motor, the field-oriented control based on the PI controller have the instability of the output torque. In order to stabilize the output torque of the permanent magnet synchronous motor, this paper adopts reinforcement learning to improve traditional PI controller. Finally, in the MATLAB/Simulink simulation environment, a new control method based on reinforcement learning is established. The simulation results show that the reinforcement learning control method used in this paper can improve the stability of the output torque.

Background: Soybean meal is used in animal feeds as a protein supplement but contains significant amounts of anti-nutritional factors such as trypsin inhibitor that directly inhibit digestion, absorption and utilization of nutrients. Results: Herein, we used solid state batch fermentation of soybean meal using Lactobacillus plantarum, Bacillus subtilis and Saccharomyces cerevisiae alone and in combination to alter the content of anti-nutritional compounds in the meal. A systematic analysis identified a temperature of 40℃, water content of 40 % in a 48 h fermentation that optimized the fermentation according to our goals. The digestibility of the meal increased within 36 h and by 48 h, the free amino acid content increased while glycinin, β-conglycinin and trypsin inhibitor significantly decreased and the indigestible sugars stachyose and raffinose were reduced to undetectable levels. These processes correlated with high levels of lactic acid that were responsible for an overall pH decrease. Conclusions: Bacterial and mixed fermentations increased nutritional content while eliminating anti-nutritional factors and significantly improved the nutritional quality of the soybean meal.

The progression of ischemic cerebral edema (CE) is closely related to the level of cerebral blood perfusion (CBP) and affects each other. Simultaneous detection of CBP and CE is helpful in understanding the mechanisms of ischemic CE development. In this article, a wide field of view swept-source optical coherence tomography system was used to detect CE status and CBP levels simultaneously in middle cerebral artery occlusion rats. Images reflecting these two physiological states can be reconstructed with only one C-scan. We quantify these two physiological states into four parameters, which contain two vascular parameters (vascular displacement distance and vascular perfusion density) and two edema parameters (optical attenuation coefficient and edema area). The association between the two vascular parameters and the two edema parameters was analyzed. The results show that there is a strong linear relationship between blood flow parameters and edema parameters. This work provides a new option for CE in vivo detection, and is very likely to play an important role in the development of relevant drugs or in selection of treatment options.

The occurrence and development of ischemic stroke are closely related to cerebral blood flow. Real-time monitoring of cerebral perfusion level is very useful for understanding the mechanisms of the disease. A wide field of view (FOV) is conducive to capturing lesions and observing the progression of the disease. In this paper, we attempt to monitor the whole-brain microcirculation in middle cerebral artery occlusion (MCAO) rats over time using a wide FOV swept-source OCT (SS-OCT) system. A constrained image registration algorithm is used to remove motion artifacts that are prone to occur in a wide FOV angiography. During ischemia, cerebral perfusion levels in the left and right hemispheres, as well as in the whole brain were quantified and compared. Changes in the shape and location of blood vessels were also recorded. The results showed that the trend in cerebral perfusion levels of both hemispheres was highly consistent during MCAO, and the position of the blood vessels varied over time. This work will provide new insights of ischemic stroke and is helpful to assess the effectiveness of potential treatment strategies.

Utilizing LNG cold energy in different temperature ranges with distinctive approaches is a promising option to achieve a high thermodynamic efficiency. This paper proposed a novel LNG cold energy cascade utilization (CES-ORC-DC-LNG) system by integrating cryogenic energy storage (CES), organic Rankine cycle (ORC), and direct cooling (DC) to recover LNG cold energy in the low, middle, and high temperature ranges, respectively. The optimal components and their respective fractions of the mixed working fluids in ORCs, and other key parameters were simultaneously determined by a simulation-based optimization approach which was developed in this study. Then, comprehensive energetic and exergetic analyses were conducted to compare the proposed system performance with the system in the literature to highlight the superior thermodynamic performance. The results indicated that the net power output of the CES-ORC-DC-LNG system was 103.30 kW, which was 22.48% higher than the base case. The optimal compositions of the mixed working fluids in ORC-1 (ethane: 23.73%, ethylene: 15.01%, R134a: 20.17%, and R152a: 41.09%) and ORC-2 (ethylene: 60.14%, R134a: 38.73%, R1270: 0.54%, and R134a: 0.59%) were distinctive with the net power output of 13.89 and 14.46 kW, respectively. The round trip efficiency of the proposed system was 141.88% with 19% increment compared with the base case. Furthermore, the exergetic efficiency of the CES-ORC-DC-LNG system was 73.92% which was 5.17% higher than the base case. Thus, the CES-ORC-DC-LNG system is an energy efficiency LNG cold energy cascade utilization system and can be a potential technology for large-scale cryogenic energy storage.

The type of Marx high-voltage pulse source design of avalanche transistors is introduced in this paper. There are seven stages; connection of avalanche transistors is adopted. Via the component parameters selecting, the output pulse has several nanoseconds front edges and KV level peak voltage, and extremely small trailing ringing. The results show that this circuit is simple, stable, and reliable, with a good output signal which is good at the ultra-wideband ground-penetrating radar application.

Cerebral edema is a severe complication of ischemic cerebrovascular disease, which can lead to microcirculation compression resulting in additional ischemic damage. Real-time and continuous in vivo imaging techniques for edema detection are of great significance to basic research on cerebral edema. We attempted to monitor the cerebral edema status in rats with middle cerebral artery occlusion (MCAO) over time, using a wide field-of-view swept-source optical coherence tomography (SS-OCT) system. Optical attenuation coefficients (OACs) were calculated by an optimized depth-resolved estimation method, and en face OAC maps covering the whole cortex were obtained. Then, the tissue affected by edema was segmented from the OAC maps, and the cortical area affected by edema was estimated. Both magnetic resonance image (MRI) and brain water content measurements were used to verify the presence of cerebral edema. The results showed that the average OAC of the ischemic area gradually decreased as cerebral edema progressed, and the edema area detected by SS-OCT had high similarity in position and shape to that obtained by MRI. This work extends the application of OCT and provides an option for detecting cerebral edema in vivo after ischemic stroke.

PurposeTo evaluate the effectiveness of Spot photoscreener and SW800 vision screener in detecting amblyopia risk factors in Chinese children between 4 and 6 years of age.MethodsOne hundred and thirteen children (226 eyes) underwent complete ophthalmologic examination, cycloplegic retinoscopy refraction, prism cover tests and photoscreen using both Spot (v2.1.4) and SW800 (v1.0.1.0) photoscreeners. The agreement of results obtained from photoscreener and retinoscopy was evaluated by paired t-test as well as Pearson correlation test. The sensitivity and specificity of detecting amblyopia risk factors were calculated based on the American Association of Pediatric Ophthalmology and Strabismus 2013 guidelines. The overall effectiveness of detecting amblyopia risk factors by using either photoscreener was analysed by receiver operating characteristic (ROC) curves.ResultsA strong linear agreement was observed between Spot and retinoscopy (pConclusionThe measurements of Spot and SW800 photoscreener showed a strong agreement with cycloplegic retinoscopy refraction and prism cover tests. The performance of both screeners in detecting individual amblyopia risk factors is satisfactory. ROC analysis indicates that the Spot and SW800 performed very similarly in detecting amblyopia risk factors.