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As an important component of sea cucumber viscera, sea cucumber ovum contains polypeptides, polysaccharides, saponins, and so on, which has biological activities such as enhancing immunity, antioxidant, antitumor, and improving reproductive function, and has high protein, polysaccharide and phospholipid contents. Although rich in nutrition, sea cucumber ovum is discarded as a byproduct of sea cucumber processing. In this article, the nutritional components, the composition, extraction and purification of bioactive substances in sea cucumber ovum are summarized. The biological activities and the current status of the development and utilization of sea cucumber ovum are reviewed, which will provide a scientific basis for the comprehensive utilization of sea cucumber ovum.

The brine‐seawater interface (BSI) is a unique type of groundwater‐seawater interface (GSI) characterized by the higher density of underground brine compared to seawater. This study focuses on characterizing the bay‐scale BSI morphology and identifying submarine‐groundwater discharge windows using a comprehensive in‐situ geophysical detection on the south bank of Laizhou Bay. Our findings reveal that the BSI forms an extensive mixing zone (15–20 km) without distinct contours between waters of varying salinities. The discharge windows for underground brine are located in nearshore areas with fine sand distribution and offshore pockmark areas. Hydraulic and salinity gradients drive the underground brine discharge through these windows. The aquitard window is the primary area for shallow and deep brine exchange, likely evolved from paleochannels, ancient tidal creeks, or ancient underwater barriers. These findings provide crucial modeling support for analyzing environmental evolution mechanisms and theoretical basis for planning the underground brine mining in similar coastal regions. Plain Language Summary: This study investigates a unique interface where underground brine meets seawater, known as the brine‐seawater interface (BSI). Unlike regular groundwater‐seawater interfaces, the BSI features brine that is denser than seawater. The research focused on characterizing the BSI's morphology and identifying locations where brine discharges into the sea along the south bank of Laizhou Bay. By using advanced detection methods and analyzing samples, the study found that the BSI forms a broad mixing zone of about 15–20 km. There are no clear boundaries between water of different salinities within this zone. The study also identified specific areas near the shore with fine sand and offshore pockmarks where brine discharges occur. These areas are recognized by the presence of suspended fine sediment on the seabed. The movement of brine through these discharge areas is driven by differences in water pressure and salinity. The study suggests that ancient channels and barriers underwater play a significant role in these discharge processes. Understanding these dynamics can help us manage coastal environments and predict how changes in sea and land interactions may affect them. Key Points: The bay‐scale brine‐seawater interface (BSI) is a long mixing zone with underground water salinity ranging from high to low from land to seaThe nearshore seabed fine sand area and offshore pockmarked area are the main windows for underground brine dischargeThe BSI morphology and submarine groundwater discharge/exchange windows can be identified by comprehensive geophysical detection results [ABSTRACT FROM AUTHOR]

In coastal plains, saline water intrusion (SWI) and potentially hazardous pollutants are harmful to local human health. The southern Laizhou Bay has become a typical representative of the northern silty coast due to its extensive silt sedimentation and the significant impact of human activities. This research focuses on a portion of the southern Laizhou Bay, using GIS-based spatial analysis, water quality index methods and health risk assessments to evaluate the impact of saltwater intrusion and potential hazardous pollutants. The results show that the groundwater in the study area is significantly impacted by saline water intrusion, leading to major ion concentrations that far exceed World Health Organization (WHO) standards. The groundwater chemical types of brine and brackish water in the study area are mainly Cl-Na, and the main chemical types of fresh water are HCO3-Ca·Na. The average concentration sequence of the main ions in groundwater is K+ > HCO3− > Cl− > Na+ > SO42− > Ca2+ > Mg2+. The average hazard quotient (HQ) sequence in typical pollutants is Cl− > F− > NO3-N > Se > Mn > NO2-N > Cu > Pb > Zn > Fe, and the carcinogenic risk (CR) sequence caused by carcinogenic heavy metals is Cd > As > Cr. The noncarcinogenic health risk area is mainly distributed in the northwest of the study area, while the potential carcinogenic risk area is in the central region. The Cl is the greatest noncarcinogenic risk to adults and children. The mean HQ values for adults and children were 95.69 and 146.98, indicating a significant noncarcinogenic risk. The mean CR values for adults and children were 0.00037 and 0.00057, suggesting a relatively low carcinogenic risk. SWI is the main influencing factor on human health; therefore, it is necessary to prevent and control SWI. Moreover, potentially hazardous pollutants are carcinogenic and noncarcinogenic risks and are caused by agriculture, industry and other human activities. The findings of this research offer scientific insights for groundwater pollution control and saline water intrusion management in similar coastal areas. [ABSTRACT FROM AUTHOR]

Cavitation inception generally originates from gaseous nuclei in a liquid, either as an air pocket on a solid wall or freely suspended gaseous contaminants. In this work, the impact of nanoscale nuclei, typically around 100 nm in diameter, on laser-induced cavitation is explored. The experimental results indicate that the presence of these nanoscale entities can readily trigger multiple optical breakdowns, resulting in a spark column with essentially discrete character and a train of primary cavitation bubbles nucleating along the laser-focusing path. The investigation further reveals a nuanced relationship between laser pulse energy and cavitation bubble size, moderated by nanoscale nuclei concentration, which ultimately caps the maximal bubble size to approximately 300 μ m. The study also delves into the aftermath of initial breakdowns, elucidating the genesis of secondary cavitation through the expansion of both pre-existing and laser-excited nanoscale gaseous nuclei, facilitated by a transient negative pressure field that is formed by the reflection of shock waves on adjacent bubbles' surface. Molecular dynamics simulations demonstrate the scenario at a smaller scale and reveal that the presence of nanobubbles is more conducive to the rupture of the surrounding water under the action of tension waves to generate cavities. This work may lay a foundational framework for future explorations aimed at decrypting the thresholds of cavitation inception, thereby enriching the academic discourse on the control and manipulation of cavitation phenomena within liquid mediums. [ABSTRACT FROM AUTHOR]

Bulk nanobubbles, nanoscopic gaseous domains in aqueous solutions, exhibit surprising long-term stability and unique properties under varying environmental conditions. This study investigates the effects of external pressure on nanobubble stability and behavior through three experimental setups: pressurization at room temperature, pressurization at elevated temperatures, and constant pressure loading. Our findings reveal that increasing external pressure reduces nanobubble concentration and reshapes the bubble size distribution. Larger nanobubbles either disappeared or transformed into microbubbles, while smaller ones expanded, significantly narrowing the size distribution. These changes were found to be irreversible. Additionally, nanobubble stability is influenced by both the magnitude and duration of the applied pressure. Elevated temperatures further narrowed the size distribution at atmospheric pressure, and subsequent pressurization caused these nanobubbles to shrink, showing different response characteristics compared to room temperature. This research highlights the complex interplay between pressure, temperature, and nanobubble stability, offering valuable insight for practical applications in fields such as drug delivery, water treatment, and nanomaterial synthesis. [ABSTRACT FROM AUTHOR]

Aiming at the intelligent demand for tomato picking operation in plant factories, in order to overcome the problems of low recognition accuracy and low speed caused by different sizes and overlapping of tomato fruits during picking operation, an improved target recognition model of YOLOX-L-TN was proposed, in which a TN module containing residual structure was designed according to the internal structure and principle of channel and spatial attention mechanism of feature graph, and integrated into the backbone network of YOLOX-L. This model improved the speed and accuracy of model recognition while maintaining the lightweight of the network. Compared with YOLOX-L, the AP value of YOLOX-L-TN was increased by 4.81 percentage points, and the recognition time of single image is increased by 0.141 7 s, and the optimal position of TN module was between the input and the backbone network. Furthermore, TN module was compared with similar modules SENet, CAM, CBAM and CAM, and the results showed that AP value was increased by 0.53, 4.19, 6.12 and 6.34 percentage points, respectively, and the recognition time of single image is increased by 0.019 1, 0.025 0, 0.021 1, 0.018 9 s, respectively. In conclusion, the proposed YOLOX-L-TN model had the advantages of high precision, fast identification speed and high robustness, which provided technical support for the intelligent picking of tomatoes in the later stage. [ABSTRACT FROM AUTHOR]