The world\'s largest green tide, caused by the nuisance green algae Ulva prolifera, has occurred in the southern Yellow Sea for 16 consecutive years. It is puzzling why the extensive floating green tide occurs exclusively in the southern Yellow Sea, rather than other waters. We speculate that the transition of U. prolifera from a sessile state to a surface-floating one is the underlying cause of the floating green tide. Here we founded that the floating of U. prolifera was attributed to detachment from substrata and appropriate desiccation. The convergence of unreasonable green algae disposal, geographical features and farming patterns of Porphyra (economic red algae) in Subei Shoal contributed to mass production of floating U. prolifera, resulting in the exclusive occurrence of the floating green tides. Inducing the natural inactivation of green algae to prevent the floating of U. prolifera may effectively mitigate the extensive Ulva bloom at zero cost.

Aspergillus niger (A. niger) spores can induce numerous health problems. Once the airflow-imposed drag force on an A. niger spore exceeds its binding force with the colony, the spore is detached. Turbulent flow may considerably increase the spore detachment. No method is currently available for prediction of the drag force on a spore and its detachment in turbulent flows. This investigation measured the turbulent velocities and detachment of A. niger colonies in a wind tunnel. Computational fluid dynamics (CFD) was employed to model an A. niger unit subjected to turbulent flow blowing. The top 1 % quantile instantaneous velocity of the turbulent flow was specified as the steady entry flow boundary condition for solving the peak velocity distribution and the peak drag forces onto spores. The predicted spore detachment ratios were compared with the measurement data for model validation. The results revealed that the spore detachment ratios with a turbulence intensity of 17 % to 20 % can be twice to triple the ratio with a turbulence intensity of approximately 1 %, when the average velocity for blowing remains the same. The proposed CFD model can accurately predict the detachment ratios of the A. niger spores. ENVIRONMENTAL IMPLICATION: Some people are sensitive to the Aspergillus niger (A. niger) spores, and excessive exposure can cause nasal congestion, skin tingling, coughing, and even asthma. Turbulent flow can considerably increase the spore detachment, due to the increased airflow-imposed drag force on the spores during turbulence. This investigation developed a numerical model to solve for the peak velocity distribution and the peak drag forces onto spores in turbulent flows to predict the spore detachment. With the numerical tool, the airborne fungal spore concentrations would be predictable, which paves a way for intelligent and precise control of fungal aerosol pollution.

Environmental stressors such as salinity fluctuations can significantly impact the ecological dynamics of mussel beds. The present study evaluated the influence of hyposalinity stress on the detachment and survival of attached mussels by simulating a mussel farming model in a laboratory setting. Byssus production and mechanical properties of thread in response to varying salinity levels were assessed, and histological sections of the mussel foot were analyzed to identify the changes in the byssus secretory gland area. The results showed that hyposalinity stress (20 and 15 psu) led to a significant decrease in mussel byssus secretion, delayed initiation of new byssus production, and reduced plaque adhesion strength and breaking force of byssal threads compared to the control (30 psu) (p < 0.05). The complete suppression of byssal thread secretion in mussels under salinity conditions of 10 and 5 psu, leading to lethality, indicates the presence of a blockade in byssus secretion when mussels are subjected to significant physiological stressors. Histological analysis further demonstrated a decrease in the percentage of foot secretory gland areas in mussels exposed to low salinities. However, contrary to expectations, the study found that mussels did not exhibit marked detachment from ropes in response to the reduced salinity levels during one week of exposure. Hyposalinity stress exposure reduced the byssal secretion capacity and the mechanical properties of threads, which could be a cause for the detachment of suspension-cultured mussels. These results highlight the vulnerability of mussels to hyposalinity stress, which significantly affects their byssus mechanical performance.

BACKGROUND: There are very few cases of cardiac occluder detachment, and it is rare to completely remove the occluder using interventional methods without undergoing thoracotomy surgery after detachment. This case innovatively used ultrasound guidance combined with digital subtraction angiography (DSA) to completely remove the occluder, accumulating some experience.
METHODS: The patient underwent left atrial appendage occlusion surgery in our hospital due to atrial fibrillation. After the surgery, the occluder fell off and became free in the left ventricle, which is very dangerous. We innovatively used ultrasound guidance, combined with DSA, and interventional surgery to successfully capture the free occluder using a catcher, completely remove it, and then re implant a new left atrial appendage occluder. After the surgery, the patient recovered very well.
CONCLUSIONS: The size selection of the occluder is slightly conservative, and the shape of the left atrial appendage opening is irregular.

Detachment of fungal spores from growing colonies results in human exposure. Thus far, the distribution of the binding forces of the spores in a fungal unit is unknown, so that precise prediction of the spores detachment is quite challenging. This investigation used centrifugal separation to measure the binding forces of the spores. Aspergillus niger (A. niger) colonies on a culture plate were placed in a centrifuge, the detached spores were counted, and this number was used to obtain the distribution of binding forces. Next, the air-blowing of an A. niger unit was modeled by computational fluid dynamics (CFD). A spore was judged to be detached if the air-imposed drag force was greater than the binding force. For model validation, the predicted spore detachment ratios were compared with the ratios measured in a wind tunnel test. The results revealed that the binding forces of the spores obeyed the log-normal distribution. The binding forces of the distal spores from colonies with a growth age of 66 h ranged from 0 nN to 4.0 nN and had a mean of 0.65 nN. The CFD modeling predicted the detachment ratios of the distal spores with good accuracy.

Microbubble generation and manipulation play critical roles in diverse applications such as microfluidic mixing, pumping, and microrobot propulsion. However, existing methods are typically limited to lateral movements on customized substrates or rely on specific liquids with particular properties or designed concentration gradients, thereby hindering their practical applications. To address this challenge, this paper presents a method that enables robust vertical manipulation of microbubbles. By focusing a resonant laser on hydrophilic silica-coated gold nanoparticle arrays immersed in water, plasmonic microbubbles are generated and detach from the substrates immediately upon cessation of laser irradiation. Using simple laser pulse control, it can achieve an adjustable size and frequency of bubble bouncing, which is governed by the movement of the three-phase contact line during surface wetting. Furthermore, it demonstrates that rising bubbles can be pulled back by laser irradiation induced thermal Marangoni flow, which is verified by particle image velocimetry measurements and numerical simulations. This study provides novel insights into flexible bubble manipulation and integration in microfluidics, with significant implications for various applications including mixing, drug delivery, and the development of soft actuators.

The adsorption and detachment processes of n-dodecane (C12H26) molecules were studied on silica surfaces with variable surface chemistry (Q2, Q3, Q4 environments), using molecular dynamics simulations. The area density of the silanol groups varied from 9.4 to 0 per nm2. The shrinking of the oil-water-solid contact line was a key step for the oil detachment, due to water diffusion on the three-phase contact line. The simulation results showed that oil detachment was easier and faster on a perfect Q3 silica surface which had (≡Si(OH))-type silanol groups, due to the H-bond formation between the water and silanol groups. When the surfaces contained more Q2 crystalline type which had (≡Si(OH)2)-type silanol groups, less oil detached, due to the formations of H-bonds among the silanol groups. There were no silanol groups on the Si-OH 0 surface. Water cannot diffuse on the water-oil-silica contact line, and oil cannot detach from the Q4 surface. The detachment efficiency of oil from the silica surface not only depended on the area density, but also on the types of silanol groups. The density and type of silanol groups depend on the crystal cleavage plane, particle size, roughness, and humidity.

Research has suggested a contradictory effect between detachment and reinterpretation, two distinct tactics of cognitive reappraisal, in the regulation of negative emotion. The reasons for this contradictory effect remain unclear. The present study explored the differences between these tactics in terms of potential early processes and neural mechanisms, comparing psychophysiological differences using event-related potentials (ERPs) in the regulation of negative emotion. Thirty college students were required to perform an emotion regulation task, in which they naturally viewed or applied a given emotion regulation strategy towards negative pictures. The results demonstrated that both tactics reduced emotional experiences (decrease of arousal and increase of valence). Reinterpretation was associated with reductions in the late positive potential (LPP) in the late time window, while detachment was not. Detachment showed a lower amplitude in the N1 and N2 ERP components and a higher P2 amplitude than reinterpretation. The differences in early ERP components (N1, N2, and P2) predicted the reduction of LPP amplitude. These findings reveal the differential effects of these tactics on emotional experience and neural responses and highlight the significance of early processes on emotion across the time course of cognitive reappraisal.

UNASSIGNED: The study aims to investigate the functional outcome of the lateral approach for insertional Achilles tendinitis (IAT) with Haglund deformity.
UNASSIGNED: From January 2016 to September 2019, 14 cases of IAT with Haglund deformity that resisted conservative treatment received surgery in our department. A lateral approach was used to debride the bony and soft tissue and reattach the insertion of the Achilles tendon. The Visual Analog Scale (VAS), American Orthopedic Foot and Ankle Score (AOFAS), and Victorian Institute of Sport Tendon Study Group-Achilles Tendinopathy score (VISA-A) were used to evaluate clinical outcomes.
UNASSIGNED: The mean patient age was 39.57 years at the time of surgery. The mean follow-up was 14.74 months. The mean VAS score significantly decreased from 4.86 ± 0.86 preoperatively to 1.21 ± 1.58 postoperatively (P < 0.001). The mean AOFAS score significantly improved from 66.64 ± 6.23 preoperatively to 90.21 ± 11.50 postoperatively (P < 0.001). The mean preoperative and the last follow-up VISA-A were 66 (range 56.75-69.25) and 86 (range 75.75-97.00) points, respectively (P < 0.05).
UNASSIGNED: The lateral approach was effective and safe for IAT with Haglund deformity. Moreover, the mid-term functional outcome was promising.
UNASSIGNED: IV.

Quantitative assessment of the responses of biofilm structure to external hydrodynamics is critical for understanding biofilm detachment mechanisms. This study used multidimensional imaging and numerical simulation approaches to elucidate the complex relationships between biofilm detachment and hydrodynamics with Shewanella oneidensis MR-1. By integrating real-time confocal laser scanning microscopy (CLSM) images with image analysis tools, the three-dimensional structural changes occurring in thin MR-1 biofilms (<10 μm) under hydrodynamic treatment at a flow velocity of 0.42 × 10-3 to 3.3 × 10-3 m/s in the laminar flow regime were visualized in situ and quantified with single-cell resolution. Analyses of the imaging results revealed high spatial heterogeneity in the degree and intensity of biofilm detachment. Spots with thick and rough biofilm surfaces or high flow rates had high detachment rates, indicating that local biofilm morphology, including thickness and roughness, and hydrodynamic flow conditions collectively controlled the detachment rate. Numerical simulations revealed a significant correlation between local detachment events and the shear stress induced by hydraulic flow at the three-dimensional level. Compared to the even or thin biofilm, a thick or rough structure might induce a 2-fold increase in shear stress over local biofilm surfaces at a microscale dimension. The results provide quantitative and microscopic insights into biofilm detachment processes in subsurface environments, especially in domains under dynamic flow conditions, such as those in hyporheic zones. The relationship between biofilm detachment and hydrodynamics and biofilm structural factors can be integrated into reactive transport models used to describe microbial growth and transport in porous media. IMPORTANCE Detachment is an important process determining the structure and function of bacterial biofilm, which has significant implications for biogeochemical cycling of elements, biofilm application, and infection control in clinical settings. Quantifying the responses of biofilm structure to hydrodynamics is crucial for understanding biofilm detachment mechanisms in aquatic environments. In this work, the spatial and temporal changes occurring in biofilm structures in response to different hydrodynamic conditions were studied by using flow cell reactors. We established the quantitative relationships among detachment, biofilm morphology, and shear stress induced by changes in hydrodynamic conditions. This work provides a quantitative understanding of the complex relationship between biofilm detachment and hydrodynamics in natural environments.