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China's Danxia landforms are characterized by their indicative red color. Portable ground object spectrometers are widely used owing to their small size, ease of operation in the field, rapid measurements, and simple operation. In this study, we analyzed the characteristic parameters of the reflection spectra of the Danxia rock wall surfaces (i.e., red surfaces, orange surfaces, and pure white spots) and different types of plant cover, as well as their quantitative relationships with color tones, using the visible-near-infrared (VNIR) reflectance spectra of the rock walls. The results indicate that the absorption depths and areas of the red and orange surface samples were highly correlated at 525 and 500 nm, as were the redness and orangeness of the samples. The redness and orangeness of the indoor and outdoor samples were relatively consistent with the absorption depth and area growth rates; however, the indoor samples had larger absorption depth and area values. The absorption depth and area of the pure white spots at 530 nm was highly correlated with redness, but the red surface and pure white spot spectra exhibited considerably different redness values, absorption depths, and absorption areas at 525–530 nm. Thus, these are advantageous parameters for distinguishing between the two surface types. The absorption positions of the red surfaces, orange surfaces, and pure white spots in the visible spectrum differed considerably, which is likely related to changes in the iron mineral types and contents present in the strata. Compared to the red surface absorption position at 525 nm, that of the orange surface shifted in the shortwave direction to 500 nm, which may be related to lower hematite and higher goethite contents. The absorption of the pure white spots at 430 nm may be caused by their pyrite content. The absorption depths of black, blocky, and green plants at 670 nm were considerably correlated with Normalized Difference Vegetation Index(NDVI). The NDVI values and absorption depths of the three plant types had widely differing range distributions, which can serve as a basis for distinguishing among the three plant types. The absorption depths of non-white spot and white spot plant coverings at 670 nm also increased with increasing NDVI values. The absorption positions of pure white spots in the visible spectrum were 430, 530, and 690 nm. After plants attached to the white spots, the 430 nm absorption position disappeared while that at 530 nm shifted in the shortwave direction. The absorption position at 690 nm was converted into that of chlorophyll. This study provides a reference for quantitatively investigating the color tones of the Danxia rock walls using VNIR reflectance spectroscopy.

Marine geothermal energy is rich in China but have not been well developed. Integrating marine geothermal energy with other marine resources is crucial for ensuring China’s energy security, realizing the carbon peak and carbon neutrality goals, strengthening the country’s energy sector, building a new energy system, and promoting island and deep-sea development. This study reviews the current status of marine geothermal energy utilization in China and abroad, analyzes the challenges faced by China in marine geothermal energy utilization, and clarifies the key development directions of marine geothermal energy utilization in China: (1) core technologies and key equipment for the exploration and development of marine geothermal energy, (2) core technologies and key equipment for marine geothermal energy utilization, and (3) marine geothermal energy industry and industrial chain construction. Moreover, the study expounds on the staged development goals and proposed two typical models for marine geothermal energy utilization in China: integrated development with offshore heavy oil and with marine natural gas hydrate. Future development strategies are further proposed: (1) coordinating marine function zoning and incorporating marine geothermal energy and offshore oil and gas blocks into unified national planning; (2) pinpointing the distribution of marine geothermal energy in South China Sea and its overlapping advantages with other marine resources; (3) accelerating research on core technologies and key equipment for the development and utilization of marine geothermal energy; (4) increasing financial support and providing subsidies and preferential fiscal and tax policies to fully mobilize the enthusiasm of enterprises; and (5) conducting pilot tests in marine geothermal energy enrichment areas to explore the demonstrations of integrated development with other marine resources.

To strengthen its energy sector and realize the carbon peaking and carbon neutrality goals, China needs to accelerate the construction of a modern energy system, transform its energy development mode, and improve its energy production support capabilities. The integration and complementarity of multiple energy sources is an effective concept and scheme to solve the separation of energy subsystems, optimize the energy pattern, and improve the efficiency of clean energy utilization. Based on the analysis of the existing modes of multi-energy integration, this study summarizes the development status and bottlenecks of multi-energy integration in China and the development trend of multi-energy integration in other countries. Considering existing models, a new multi-energy integration model that integrates energy conversion, complementarity, reuse, and zero-carbon production is proposed to achieve the clean and efficient utilization of energy. To promote the planning, construction, and practice of multi-energy integration in China, we further propose a basic development path and the following suggestions: (1) formulating a medium- and long-term plan to support multienergy integration based on resource endowment, (2) accelerating the breakthroughs in key core technologies for multi-energy

Abstract Background Due to the increasing incidence of ischaemic cerebrovascular diseases, the accurate assessment of internal carotid artery (ICA) stenosis is crucial for the development of treatment plans. This systematic review and meta-analysis aimed to evaluate the diagnostic value of computed tomography angiography (CTA) for severe ICAstenosis, thereby providing support for clinical decision-making and promoting diagnostic updates. Methods The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database for Chinese Technical Periodicals (VIP), and Chinese Biomedical Literature (CBM) electronic databases were searched from inception to March 21, 2024, to identify publicly available research literature on the use of CTA to diagnose severe ICA stenosis. Literature screening, data extraction, and quality assessment were conducted based on the inclusion and exclusion criteria as well as the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) standards. Data analysis was performed using Stata 17.0 and Meta-Disc 1.4 software. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of the included studies were calculated using Stata 17.0 software, and forest plots and summary receiver operating characteristic (SROC) curves were generated. The area under the curve (AUC) was calculated, and funnel plots were constructed to assess publication bias. Results A total of 16 studies with 2368 vascular segments were included. The meta-analysis revealed that the combined sensitivity and specificity of CTA for severe ICA stenosis were 0.93 (95% CI: 0.88 ~ 0.96) and 0.99 (95% CI: 0.96 ~ 1.00), respectively. The combined positive likelihood ratio and negative likelihood ratio were 92.0 (95% CI: 24.2 ~ 349.6) and 0.07 (95% CI: 0.04 ~ 0.13), respectively. The diagnostic odds ratio was 1302 (95% CI: 257 ~ 6606), and the AUC of the SROC curve was 0.98. The Deeks funnel plot suggested no publication bias among the included studies. Conclusion CTA demonstrated high sensitivity and specificity for diagnosing severe ICA stenosis. Therefore, this study provided important evidence for the accurate diagnosis and treatment of severe ICA stenosis. However, there was considerable heterogeneity among the included studies, thus indicating the need for additional high-quality prospective studies to confirm the clinical applicability of CTA.

AIM: To review and summarize the mechanism hypothesis, influencing factors and possible consequences of macular retinal displacement after idiopathic macular hole (IMH) surgery. METHODS: PubMed and Web of Science database was searched for studies published before April 2023 on “Retinal displacement”, “Idiopathic macular holes”, and “Macular displacement”. RESULTS: Recently, more academics have begun to focus on retinal displacement following idiopathic macular holes. They found that internal limiting membrane (ILM) peeling was the main cause of inducing postoperative position shift in the macular region. Moreover, several studies have revealed that the macular hole itself, as well as ILM peeling method, will have an impact on the result. In addition, this phenomenon is related to postoperative changes in macular retinal thickness, cone outer segment tips line recovery, the occurrence of dissociated optic nerve fiber layer (DONFL) and the degree of metamorphopsia. CONCLUSION: As a subclinical phenomenon, the clinical significance of postoperative macular displacement cannot be underestimated as it may affect the recovery of anatomy and function.

This article aims to provide a novel image paradigm for camouflaged object detection, i.e., RGB-D images. To promote the development of camouflaged object detection tasks based on RGB-D images, we construct an RGB-D camouflaged object detection dataset, dubbed CODD. This dataset is obtained by converting the existing salient object detection RGB-D datasets by image-to-image translation techniques, which is comparable to the current widely used camouflaged object detection dataset in terms of diversity and complexity. In particular, in order to obtain high-quality translated images, we design a selection strategy that takes into account the structural similarity between pre- and post-conversion images, the similarity between the appearance of objects and their surroundings, as well as the ambiguity of object boundaries. In addition, we extensively evaluate the CODD dataset using existing RGB-D-based salient object detection methods to validate the challenge and usability of the dataset. The CODD dataset will be available at: https://github.com/zcc0616/CODD-Dateset.git.

In this paper, the similarity criterion and dimensionless conversion method combined with the elasticity condition and Hooke's law are used to derive the functional relationship of the maximum effective value of the vibration velocity between the prototype pump and the model pump. The seawater circulation pump of a nuclear power plant is used as the prototype pump, and the model pump is obtained by performance conversion and choosing the appropriate scale, and the vibration state of the model pump under different flow rates is measured and analyzed. The vibration data of the model pump through the function relationship to find out the vibration parameters of the prototype model pump, and compare with the vibration data of the seawater circulation pump in reality. It can be seen that with the increase of flow rate, the maximum effective value of the vibration velocity of both model and prototype decreases and then increases, and the relative error is small, the maximum value is 7.7757%. Therefore, it can be considered that the functional relationship of model pump converted to prototype pump derived in this paper can be used to analyze the vibration of the actual seawater circulation pump of coastal nuclear power plant.

BackgroundThe proliferation of mobile health apps has greatly changed the way society accesses the health care industry. However, despite the widespread use of mobile health apps by patients in China, there has been little research that evaluates the effect of mobile health apps on patient experience during hospital visits. ObjectiveThe purpose of our study was to examine whether the use of mobile health apps improves patient experience and to find out the difference in patient experience between users and nonusers and the characteristics associated with the users of these apps. MethodsWe used the Chinese Outpatient Experience Questionnaire to survey patient experience. A sample of 300 outpatients was randomly selected from 3 comprehensive public hospitals (3 tertiary hospitals) in Hubei province, China. Each hospital randomly selected 50 respondents from mobile health app users and 50 from nonusers. A chi-square test was employed to compare the different categorical characteristics between mobile health app users and nonusers. A t test was used to test the significance in continuous variables between user scores and nonuser scores. Multiple linear regression was conducted to determine whether the use of mobile health apps during hospital visits was associated with patient experience. ResultsThe users and nonusers differed in age (χ22=12.2, P=.002), education (χ23=9.3, P=.03), living place (χ21=7.7, P=.006), and the need for specialists (χ24=11.0, P=.03). Compared with nonusers, mobile health app users in China were younger, better educated, living in urban areas, and had higher demands for specialists. In addition, mobile health app users gave significantly higher scores than nonusers in total patient experience scores (t298=3.919, P