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Underwater optical communication is a new and feasible underwater communication technology, which has developed rapidly in recent years. To build a high-performance and practical underwater optical communication system, it is necessary to consider and optimize the design from the device to the system, from the internal modulation to the external environment. This paper summarizes the current problems of underwater optical communication from the aspects of underwater optical communication system transmitter and receiver, modulation format and underwater channel. The paper also classifies and summarizes the three key technologies of improving underwater optical communication distance, communication rate and communication stability, and gives the possible solutions. It provides reference for the follow-up system design and experimental research.

People's livelihood issues are related to their basic needs and interests, and the use of information and communication technologies (ICTs), which enable citizens to actively participate in the governance of people's livelihood issues, has revolutionized the paradigm of managing and regulating affairs and issues in the city. Although livelihood issues are different from physical objects, they occur in a specific space, are still affected by many geospatial factors, and should also exhibit specific spatial characteristics. To investigate the spatial characteristics and influencing factors of livelihood issues in the main urban areas of Chengdu City, the study was based on the data of livelihood issues in Chengdu City's online governance platform. First, it explored the spatial and temporal distribution characteristics of livelihood issues in the main urban areas of Chengdu City by using spatial analysis. It then analyzed the influencing factors of the spatial differentiation of livelihood issues by using text analysis and Geodetectors, and finally put forward the countermeasures for governance of livelihood issues. The results show that holidays and temperature changes may affect the intensity of people's daily activities and regulate the periodicity of production and life, causing the number of livelihood issues to change with the seasons, showing an increase in the number of livelihood issues in spring and fall, and a decrease in the number of livelihood issues in summer and winter. The cold spots and hot spots of livelihood issues are characterized by marginalization and concentration in space. The livelihood issues in the categories of residents' life, road traffic, housing and land, social service, city environment, and building production are spatially clustered, with the kernel density values decreasing from the center to the periphery, and the high-value areas dispersed in the form of small clusters. The overall explanatory power of commercial conditions and public service conditions in explaining the spatial differentiation of livelihood issues surpasses that of demographic conditions and traffic conditions. This study expands the research path of livelihood issues, enriches the data sources, and supplements the research on livelihood issues at small scales with subdistricts as the research unit. The study's findings can aid in identifying the spatial and temporal patterns of livelihood issues, and serve as a foundation for devising strategies to prevent and address livelihood issues. Practical Applications: In the context of the digital era, the application of an online governance platform makes urban governance more intelligent and efficient. As a critical component of urban governance, livelihood issues are inextricably linked to people's daily lives. The majority of current research focuses on the governance of livelihood issues; nevertheless, there is still a lack of research into whether livelihood issues have specific spatial characteristics and what variables influence their spatial distribution. We collected data on livelihood issues with spatial attributes using an online governance platform. After conducting spatial analysis, we discovered that the characteristics of the spatial distribution of livelihood issues show the marginalization and concentration of subdistricts with low rates of livelihood issues and notably concentrated livelihood issues, and that livelihood issues are more frequent at the junction of subdistricts. The density of commercial and public service facilities has a stronger influence on the distribution of livelihood issues than the density of transportation and demographic conditions. This study takes a novel approach to studying livelihood issues by conducting in-depth analyses of spatial and temporal distribution characteristics, as well as influencing factors, and can serve as a foundation for the development of urban governance countermeasures, thereby improving the effectiveness of urban governance and urban development quality. [ABSTRACT FROM AUTHOR]

Noble metal-loaded semiconductor photocatalysts have attracted extensive attention in the field of photocatalytic two-electron oxygen reduction to generate H2O2 due to their high atomic utilization rate. However, the rareness and high cost of materials significantly hinder their industrial application. Here, we introduce phosphate as an electron bridge in carbon nitride (C3N5)-cobalt phthalocyanine (CoPc) (C3N5-YP-XCoPc) to enable the accurate transmission of photogenerated electrons to the metal Co atoms, and then excite them as catalytic centers to achieve the efficiency of a noble metal-like loaded semiconductor photocatalyst. The photocatalytic H2O2 yield of C3N5-8P-0.9CoPc is as high as 3080.3 μmol g−1 h−1, which is 8.3 and 4.4 times higher than C3N5 and C3N5-0.9CoPc, respectively. Experimental and theoretical calculations demonstrate that photogenerated electrons are precisely transported to Co atoms via phosphate molecules, exciting the Co 3d orbitals to higher energy levels, thereby making the Co atoms catalytic centers and enhancing their ability to adsorb and activate O2. Meanwhile, phosphate passivated the adsorption of H2O2 on C3N5-8P-0.9CoPc and inhibited the in situ decomposition of H2O2. This work opens up new perspectives for the development of efficient photocatalysts, while demonstrating the potential of small molecules as bridging mediators. [ABSTRACT FROM AUTHOR]

In coastal erosion studies, the erosion and accretion index is a vital research tool for analyzing types of erosion and accretion. This index is primarily empirical or semi-empirical and is usually validated through tank experiments or open beach datasets, resulting in significant variation across different beach environments. In this study, 11 beach profiles of eight beaches measured along the Qiongzhou Strait in China, measured from 2018 to 2021, were analyzed to quantitatively determine coastal erosion or accretion by calculating each profile's volume change per unit width. Additionally, sediment and wave data were used to calculate five erosion and accretion indices monthly to determine erosion and accretion conditions. These conditions were then compared with actual beach erosion and accretion data to evaluate the applicability of various discriminant indices. Furthermore, optimizing the threshold values of discriminant indices. The results show that: (1) Overall annual erosion and accretion are minimal, but seasonal variation is significant for beaches on both sides of the Qiongzhou Strait; (2) The five discriminant indices have some limitations in this study area, necessitating careful consideration when applying them to headland bay arc-shaped beaches with fetch-limited environments like the Qiongzhou Strait; (3) The selection of discriminant index parameters and their respective contribution degree of each parameter affects the formula's applicability, with two-parameter formulas proving superior to the three-parameter formula in the study area; (4) Beach environmental factors, particularly those influenced by headlands and fetch-limited environments, impact the indices' applicability; (5) Increasing the threshold value to a certain extent can improve the formula's applicability. [ABSTRACT FROM AUTHOR]

Summary: Background and Aims: Extracorporeal shock wave lithotripsy for pancreatic stones (P‐ESWL) and endoscopic retrograde cholangiopancreatography (ERCP) are the preferred therapeutic approaches for painful chronic pancreatitis (CP) with pancreatic stones. This study aimed to report the short‐ and long‐term outcomes following P‐ESWL and ERCP in a large cohort with CP. Methods: Patients with painful CP and pancreatic stones >5 mm in size, who underwent P‐ESWL and subsequent ERCP between March 2011 and June 2018, were included in this retrospective‐prospective mixed observational study. The total stone clearance rates were recorded. All patients were followed up until the end of March 2024, with the visual analogue scale (VAS) for pain, pain type, quality‐of‐life scores and other relevant information recorded. Results: A total of 2071 patients underwent P‐ESWL, and 93.1% of them subsequently underwent ERCP during the study period. Patients were followed up for an average of 11.8 years from the onset of CP and 6.7 years from the first P‐ESWL procedure. Complete stone clearance was achieved in 73.7% of the patients. At the end of the follow‐up period, 70.1% of the patients achieved complete pain remission. Significant pain type conversion and lower VAS scores were observed in the patients after treatment. Quality‐of‐life scores and body mass indices increased after P‐ESWL and ERCP. Conclusions: P‐ESWL and ERCP are effective and minimally invasive treatments for pancreatic stones in patients with painful CP. Most patients achieved complete pain relief, and pain‐type conversion was common after treatment. (ClinicalTrials.gov: NCT05916547). [ABSTRACT FROM AUTHOR]

Background: Evidence linking air pollutants and the risk of schizophrenia remains limited and inconsistent, and no studies have investigated the joint effect of air pollutant exposure and genetic factors on schizophrenia risk. Aims: To investigate how exposure to air pollution affects schizophrenia risk and the potential effect modification of genetic susceptibility. Method: Our study was conducted using data on 485 288 participants from the UK Biobank. Cox proportional hazards models were used to estimate the schizophrenia risk as a function of long-term air pollution exposure presented as a time-varying variable. We also derived the schizophrenia polygenic risk score (PRS) utilising data provided by the UK Biobank, and investigated the modification effect of genetic susceptibility. Results: During a median follow-up period of 11.9 years, 417 individuals developed schizophrenia (mean age 55.57 years, s.d. = 8.68; 45.6% female). Significant correlations were observed between long-term exposure to four air pollutants (PM2.5; PM10; nitrogen oxides, NOx; nitrogen dioxide, NO2) and the schizophrenia risk in each genetic risk group. Interactions between genetic factors and the pollutants NO2 and NOx had an effect on schizophrenia events. Compared with those with low PRS and low air pollution, participants with high PRS and high air pollution had the highest risk of incident schizophrenia (PM2.5: hazard ratio = 6.25 (95% CI 5.03–7.76); PM10: hazard ratio = 7.38 (95% CI 5.86–9.29); NO2: hazard ratio = 6.31 (95% CI 5.02–7.93); NOx: hazard ratio = 6.62 (95% CI 5.24–8.37)). Conclusions: Long-term exposure to air pollutants was positively related to the schizophrenia risk. Furthermore, high genetic susceptibility could increase the effect of NO2 and NOx on schizophrenia risk. [ABSTRACT FROM AUTHOR]

The widespread and complex formation of saline soils in China significantly affects the sustainable development of regional ecosystems. Intense climate changes and regional land use further exacerbate the uncertainties faced by ecosystems in saline areas. Therefore, studying the distribution characteristics of typical halophytic vegetation under the influence of climate change and human activities, and exploring their potential distribution areas, is crucial for maintaining ecological security in saline regions. This study focuses on Tamarix chinensis, Tamarix austromongolica, and Tamarix leptostachya, integrating geographic information systems, remote sensing, species distribution models, and landscape ecological risk (LER) theories and technologies. An optimized MaxEnt model was established using the ENMeval package, incorporating 143, 173, and 213 distribution records and 13 selected environmental variables to simulate the potential suitable habitats of these three Tamarix species. A quantitative assessment of the spatial characteristics and the area of their potential geographical distribution was conducted. Additionally, a landscape ecological risk assessment (LERA) of the highly suitable habitats of these three Tamarix species was performed using land use data from 1980 to 2020, and the results of the LERA were quantified using the Landscape Risk Index (LERI). The results showed that the suitable areas of Tamarix chinensis, Tamarix austromongolica, and Tamarix leptostachya were 9.09 × 105 km2, 6.03 × 105 km2, and 5.20 × 105 km2, respectively, and that the highly suitable habitats for the three species were concentrated in flat areas such as plains and basins. Tamarix austromongolica faced increasing ecological risk in 27.22% of its highly suitable habitat, concentrated in the northern region, followed by Tamarix chinensis in 16.70% of its area with increasing ecological risk, concentrated in the western and northern highly suitable habitats; Tamarix chinensis was the least affected, with an increase in ecological risk in only 1.38% of its area. This study provides valuable insights for the protection of halophytic vegetation, represented by Tamarix, in the context of China's national land development. [ABSTRACT FROM AUTHOR]

Offshore wind energy is one of the most important clean energy sources developing in China in recent years. As a new type of offshore wind turbine foundation, the wide-shallow bucket foundation with large diameter has a good ability to withstand moments. It is thus suitable for offshore region in China with soft clay deposits. Moreover, this type of foundation has advantages of onshore prefabrication, foundation-tower-turbine integrated floating transportation and suction installation, resulting in a good benefit for cost reduction. To better understand the bearing capacity of the wide-shallow bucket foundation in clay, numerical analyses are conducted to study the monotonic ultimate bearing behavior. The horizontal and moment ultimate bearing capacities and corresponding failure mechanisms are obtained. By building the velocity field based on the failure mechanisms of the bucket foundations, combined with the virtual work equation and the internal energy loss rate function, the upper bound solutions for the horizontal and moment ultimate bearing capacities of the bucket foundations are established and programmed using mathematical software. The results of the upper bound limit analysis have a good agreement with the calculation of the numerical analyses.

Objective To study the role of matrix vesicles bodies (MVBs) and interleukin-1β (IL-1β) in the vascular calcification of type 2 diabetic rats. Methods In vivo and in vitro vascular calcification models were developed by streptozotocin (STZ) plus vitamin D3 in rats with high-fat diet and β-glycerophosphate and high-glucose medium in vascular smooth muscle cells (VSMCs), respectively. Calcium deposition was detected by PET/CT, Von Kossa staining or alizarin red S staining. The expression of runt-related transcription factor 2 (RUNX 2), annexin-Ⅵ and IL-1β were detected by immunofluorescence staining, real-time quantitative PCR or Western blot. Results The aortic artery of calcified rats and the in vitro VSMCs both showed obvious calcium deposits. Compared to the control group, the expressions of bone morphogenetic protein-2 (BMP-2) and RUNX 2 significantly increased in the calcification group (P＜0.01, P＜0.05). At the same time, the expression of annexin-Ⅵ and IL-1β was also significantly up-regulated (P＜0.01, P＜0.05) and there was a co-localization between them. Rapamycin reduced expression of RUNX-2, annexin-Ⅵ and IL-1β in the calcification group (P＜0.01). After the treatment of chloroquine, the expression of RUNX 2 weas slightly up-regulated and annexin-Ⅵ was high-expressed(P＜0.01). Conclusions Autophagy reduces the release of MVBs and the expression of inflammatory factor IL-1β and so thereby reduces aortic calcification in type 2 diabetic rats.