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The biological early warning system with fish behavior as the detection index is an efficient and rapid early warning technology for the ecological damage caused by water pollutants. However, the attempt to apply the scototaxis (dark preference) behavior of fish to biological early warning is still relatively lacking. In this study, we delved into the dark and light preferences of the rare minnows (Gobiocypris rarus), employing three distinct tank configurations. Additionally, we systematically examined the modulating effects of environmental illumination, nutritional status, and the number of test subjects on this behavior, aiming to establish optimal experimental parameters for its observation. Furthermore, cadmium ions [Cd2+], tricaine methanesulfonate [MS222], and p-chloroaniline were employed as representative heavy metal ions, neuroactive agents, and organic toxicants, respectively, to test the impact of chemicals on scototaxis in gradient concentrations. The results demonstrated that the rare minnow exhibited a clear scototaxis (dark preference), and this behavior was not affected by the nutritional status of the test fish, the illumination, or the number of subjects. While the dark chamber was consistently the preferred location of rare minnows during the chemical exposure tests, the degree of scototaxis by the rare minnow significantly decreased at Cd2+ ≥ 3 mg/L, MS222 ≥ 11 mg/L, and p-chloroaniline ≥ 29 mg/L, suggesting a potential disruption of their innate behavioral patterns by these chemicals. These findings underscore the sensitivity of rare minnows to water pollutants. Therefore, the scototaxis behavior of rare minnows can be a potential and useful behavioral indicator for biological early warning, which can be used for early biological warning of sudden water pollution caused by chemicals such as Cd2+, MS222, and p-chloroaniline. [ABSTRACT FROM AUTHOR]

The use of distributed energy systems (DES) can utilize local resources to achieve flexible and efficient energy production and supply. However, this aspect of pollutant emission reduction has not been sufficiently investigated in current related studies. On this basis, this study establishes a DES system that integrates a ground-source heat pump, a gas turbine, a photovoltaic device and an energy storage device. An Improved Zebra Optimization Algorithm (IZOA) is proposed for optimizing the capacity of DES devices and the energy supply ratio of the ground-source heat pump. Using the economic cost saving rate (ECSR), pollutant emission reduction rate (PERR) and energy saving rate (ESR) as the optimization objectives, the study builds a DES configuration optimization model. By analyzing the arithmetic example of a large hotel building, the study verifies the effectiveness of the IZOA algorithm in solving the DES configuration optimization problem. This study provides useful research ideas in promoting the development of distributed energy systems, environmental protection and energy conservation. [ABSTRACT FROM AUTHOR]

There was a large amount of dredged materials produced stably in the Yangtze waterway each year. How to dispose these dredged materials was a major technical problem in the field of port and waterway engineering. The dredged materials were valuable resource, and the utilization of dredged materials in landscape can be an important direction in the future. To analyze the feasibility of dredging for landscaping, the waterway dredged sediments from middle and lower reaches of the Yangtze River basin, such as Dongting Lake, Chenglingji section, Zhenjiang section, Nantong section and Taihu Lake were collected, and the nutrient characteristics, heavy metal content and pollution degree were analyzed. The results showed that the pH, moisture content, petroleum hydrocarbons, organic matter and available P in Yangtze River waterway dredging sediments were 7.28~7.74, 3.75~28.27%, 14.21~121.84 ppm, 1.88~5.29% and 16.96~65.38 ppm respectively, which were moderate pollution and suitable for plants growth. The content of available N and available K content were 67.12~87.97 ppm and 2.78~20.11 ppm, which were too low to meet the needs of plant growth. Extra sources of nitrogen and potassium should be added into the sediments when reused. Dredged sediments were contaminated by heavy metals Cu, Pb and Zn, the evaluation results showed that their enrichment effect was not obvious, which won’t affect the sediment utilization. Dredged sediments were widely contaminated by Cd (0.05~2.68 mg/kg), and there was a certain enrichment effect, so some Cd hyperaccumulators should be planted to remediate Cd in dredged sediments.

Windbreaks projects are constructed in order to reduce the dusting in port bulk storage yards. The assessment of wind environment and dust suppression effects are important in the planning or preliminary design of such projects. This paper takes a large port bulk storage yard with 853m x 966m area as an example, velocity measurement wind tunnel tests were carried out. The wind velocity reduction ratio and dust suppression rate were used to access the wind environment and the dust suppression effect. The influence of windbreak height was investigated. The comprehensive wind speed reduction rate and dust suppression rate vary with windbreak height nearly linearly. And combined with spraying system, the dust suppression rate can reach beyond 95%, which provides reference and assessment method for relative engineering applications.

With the increasing requirements of environmental protection, a large number of new wet dust suppression technologies are used in the port in recent years, such as watering at the bottom of the Dumper Shed, etc. So the moisture content of coal is more than 10% often appear. Relevant studies show that the amount of dust from coal (conventional moisture content) pile is directly proportional to the high power of wind speed. But studies on high moisture content coal are rare. In this study, Wind tunnel test was carried out to study the dust emission behavior of coal with high moisture content (13.7% and 14.3%). The results show that the relationship between coal dust and wind speed tends to be linear under high moisture content. The study can provide a basis research for the estimation of coal dust emission in port.

Aquatic plant restoration is an important technique for the treatment of eutrophic water bodies. There are significant differences in pollutant removal efficiency among different combinations of aquatic plant species in eutrophic water bodies. Therefore, further research on the selection of suitable combinations of aquatic plant species is of great significance for the restoration of eutrophic water bodies. This study investigated the pollutant removal efficiency and bacterial community structure of three novel combinations of aquatic plants, including Lythraceae, Nymphaea, and Myriophyllum (LNM group), Lythraceae, Nymphaea, and Hydrilla verticillata (LNH group), and Lythraceae, Nymphaea, and Vallisneria (LNV group), as well as a control group (CK group). The components of the CK group were only sediment and culture water without any plants. The results show that on one hand, the LNH group had the highest removal rate of COD (90.29%); the LNV group exhibited the highest removal rates for NH4+-N and TN, with removal rates of 61.20% and 82.94%, respectively; and there was no significant difference in the removal rate of TP among the experimental groups, except for the LNH group, which showed higher initial removal efficiency for TP. On the other hand, plant combinations had different impacts on the top 13 dominant microflora at the phylum level. Proteobacteria and Actinobacteria showed the highest removal efficiency for COD in the LNH group, while Verrucomicrobi, Chloroflex, and Acidobacteria showed higher removal efficiency for NH4+-N and TN in the LNV and LNH groups. In summary, the three different combinations of aquatic plants exhibited distinct pollutant removal characteristics, significantly altered the structure of the microbial community, and provided a theoretical basis for their practical application in the restoration of eutrophic water bodies. [ABSTRACT FROM AUTHOR]

Equivalent Static Wind Loads (ESWL) are desired in structural design to consider peak dynamic wind effects. Conventional ESWLs are for structures without control. For flexible structures with vibration control devices, the investigation of ESWL is required. Inerter-based Vibration Absorbers (IVAs), due to the light weight and high performance, gained much research attention recently. This paper established a generic analytical framework of ESWL for structures with IVAs. The analytical optimal design formulas for IVAs with different configurations and installation locations are provided. Subsequently, the solutions to uncontrolled and controlled wind-induced responses are derived based on the filter approach. Finally, the ESWL for controlled structures are presented with a gust response factor approach. The ESWL estimation for a tall chimney controlled by IVAs is illustrated, and the results revealed a significant ESWL reduction effect of the IVAs, particularly for the cross-wind vortex resonance. In the presented framework, the conventional uncontrolled ESWL can be converted to the controlled one with a control ratio. The closed form solution of the control ratio is provided, which enables a quick estimation of ESWL for controlled structures particularly in the preliminary design stage. The presented approach has the potential to be extended to more complex structures and vibration control devices. [ABSTRACT FROM AUTHOR]

Strong wind has caused damage to group-arranged quayside container cranes in terminals and ports in recent years. Interference may amplify the wind loads in some cases. However, the interference effect among cranes has rarely been studied. In this study, high-frequency force balance tests were conducted to obtain the wind load of isolated and group-arranged container cranes. The results of the computational fluid dynamics simulation were validated by wind tunnel tests and provided the mean wind loads of all 15 types of member cranes. According to the results from wind tunnel tests, the fluctuating wind loads of each member were generated using the weighted amplitude wave superposition method. Based on dynamic finite element methods, the wind-induced responses were obtained considering the interference effect. It was found that the interference effect is the combined effects of both the shielding effect and the amplification of turbulence. Although in some cases the fluctuating and peak wind loads can increase by up to 16% and 6%, respectively, those in the most unfavorable cases are reduced by the interference effect. The interference factor for extreme nodal deformation is 0.56 and 0.69. The interference effect in container cranes mainly appears as a shielding effect, reducing the wind loads and response of the structures in unfavorable cases. [ABSTRACT FROM AUTHOR]

Grasslands in the Qinghai–Tibet Plateau play an important role in preserving ecological security and high biodiversity in this region. However, the distribution of the composition and structure of plant community and the mechanism by which it maintains itself in this region are still poorly understood. Here, we designed 195 grassland plots in 39 grassland sites along an approximately 1700 m elevation gradient on the Northeastern Qinghai–Tibet Plateau. We found that the grassland community height decreased significantly with increasing elevation, whereas community coverage did not significantly change. With increasing elevation, plant species richness (α diversity) increased significantly, but the community variability (β diversity) decreased significantly. The constrained clustering analysis suggested that the α- and β-diversity in the grasslands transformed gradually with elevation, and that three discontinuous points (based on community structure) were observed at elevation of 3640, 4252 and 4333 m. Structural equation modeling (SEM) indicated that the increase in precipitation and the decrease in temperature significantly positively influenced α diversity, which was negatively correlated with β diversity. These results demonstrate a quantitative-to-qualitative change in the community composition and structure along this elevational gradient on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

The ship exhaust sniffing unmanned aerial vehicle (UAV) system can be applied to monitor vessel emissions in emission control areas (ECAs) to improve the efficiency of maritime law enforcement and reduce ship pollution. To solve the problems of large size, heavy weight and high cost of ship exhaust sniffing sensors, in this paper, a unique diffused mini-sniffing sensor was designed, which provides a low-cost, lightweight, and highly adaptable solution for ship exhaust sniffing UAV. To verify the measurement accuracy of the system, a large number of on-site tests were performed based in the mouth of the Yangtze River, and some cases of violation of the fuel sulfur content (FSC) were verified and punished. Maritime law enforcement officers boarded the ship to take oil samples from eight suspected ships and sent them to the laboratory for testing. The results showed that the FSCs of the eight ships in chemical inspection were all greater than the regulatory limit 0.5% (m/m) of the International Maritime Organization (IMO). The system enables authorities to monitor emissions using rotary UAVs equipped with diffused mini-sniffing sensors to measure the FSC of navigating ships, which couple hardware and operational software with a dedicated lab service to produce highly reliable measurement results. The system offers an effective tool for screening vessel compliance. [ABSTRACT FROM AUTHOR]

Based on the demand of vehicle emission research and control, this paper presents the development of a portable vehicle measurement system (PEMS) based on SEMTECH-DS and ELPI+, the vehicle emission tests carried out on actual roads, and the data obtained for the establishment and validation of a vehicle emission model. Based on the results of the vehicle emission test, it was found that vehicle driving conditions (speed, acceleration, vehicle specific power (VSP), etc.) had a significant impact on the pollutant emission rate. In addition, local driving cycles were generated and the frequency distribution of VSP-bin under different cycles was analyzed. Then, through the establishment of an emission rate database, calculation of emission factors and validation of the emission model, a vehicle emission model based on actual road driving conditions was developed by taking VSP as the "surrogate variables". It showed that the emission factor model established in this study could better reflect the vehicle transient emissions on the actual road with high accuracy and local adaptability. Through this study, it could be found that due to the great differences in traffic development modes and vehicle driving conditions in different cities in China, the emission model based on driving conditions was a better choice to carry out the research on vehicle emission in Chinese cities. Compared with directly applying international models or quoting the recommended values of relevant macroscopic guidelines, the emission factor model established in this study, using actual driving conditions, could better reflect the vehicle transient emissions on the actual road with high accuracy and local adaptability. In addition, due to the rapid development of China's urban traffic and the rapid change of driving conditions, it was of great significance to regularly update China's urban conditions to improve the accuracy of the model, no matter which model was chosen. [ABSTRACT FROM AUTHOR]

The wind-induced damages on quayside container cranes happen occasionally in recent years, which is mostly sliding and overturning caused by transient gusty wind (particularly the "short-rise-time gust"). Therefore, studies on the stochastic dynamic transient gusty wind effect on the sliding and overturning of quayside container cranes are required. Based on aerodynamic data obtained from wind tunnel tests, dynamic transient gusty wind-induced sliding force and overturning moment responses of quayside container cranes were analyzed in the present study. Through Monte Carlo simulation based on quasi-stationary assumption, the stochastic characteristics (including statistics and probabilistic distributions) of the peak dynamic wind-induced responses of transient gusty wind and corresponding stationary gust wind were analyzed. The influences of different transient gusty wind parameters (accelerations, wind velocity change ratios) on the dynamic impact effects were discussed. As a result, the critical "start-up" acceleration was formulated. The transient gusty wind amplification factors on the dynamic responses were quantified. And the peak dynamic transient gusty wind-induced responses with a certain non-exceedance probability can be determined. [ABSTRACT FROM AUTHOR]

The presence of hypertension (HTN) in type 2 diabetes mellitus (DM) is a common phenomenon in more than half of the diabetic patients. Since HTN constitutes a predictor of vascular complications and cardiovascular disease in type 2 DM patients, it is of significance to understand the molecular and cellular mechanisms of type 2 DM binding to HTN. This review attempts to understand the mechanism via the perspective of the metabolites. It reviewed the metabolic perturbations, the biological function of perturbated metabolites in two diseases, and the mechanism underlying metabolic perturbation that contributed to the connection of type 2 DM and HTN. DM-associated metabolic perturbations may be involved in the pathogenesis of HTN potentially in insulin, angiotensin II, sympathetic nervous system, and the energy reprogramming to address how perturbated metabolites in type 2 DM affect the pathogenesis of HTN. The recent integration of the metabolism field with microbiology and immunology may provide a wider perspective. Metabolism affects immune function and supports immune cell differentiation by the switch of energy. The diverse metabolites produced by bacteria modified the biological process in the inflammatory response of chronic metabolic diseases either. The rapidly evolving metabolomics has enabled to have a better understanding of the process of diseases, which is an important tool for providing some insight into the investigation of diseases mechanism. Metabolites served as direct modulators of biological processes were believed to assess the pathological mechanisms involved in diseases. [ABSTRACT FROM AUTHOR]