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Ambient pressure has a certain inhibiting effect on underwater welding droplet transfer and the stability of welding process. Good droplet transfer of underwater welding plays an important role in improving repairing quality of underwater structures. As an additional droplet separating force, laser provides effective means in improving the welding quality. For quantitative analysis and comparison of laser enhanced effect on droplet transfer, a high-speed camera system to shoot the process of welding droplet transfer was designed and by adopting the frequency domain operation, a filter aiming at image processing of welding droplet was also designed to filter the ambient noise and diffraction fringe. Through edge detection algorithm, edges of droplet images were detected, and the size of droplet was computed accurately with welding wire as the reference. At last, droplets’ statues under different welding parameters were compared. The results show that the clear images of GMAW droplet separated from the noise background can be acquired, which makes the high-precision quantitative analysis of laser enhanced effect possible. All of the results lay a foundation for further test of laser enhanced hyperbaric underwater welding.

Organic nucleation is an important source of atmospheric aerosol number concentration, especially in pristine continental regions and during the preindustrial period. Here, we improve on previous simulations that overestimate boundary layer nucleation in the tropics and add changes to climate and land use to evaluate climate forcing. Our model includes both pure organic nucleation and heteromolecular nucleation of sulfuric acid and organics and reproduces the profile of aerosol number concentration measured in the Amazon. Organic nucleation decreases the sum of the total aerosol direct and indirect radiative forcing by 12.5%. The addition of climate and land use change decreases the direct radiative forcing (-0.38 W m-2) by 6.3% and the indirect radiative forcing (-1.68 W m-2) by 3.5% due to the size distribution and number concentration change of secondary organic aerosol and sulfate. Overall, the total radiative forcing associated with anthropogenic aerosols is decreased by 16%.

Isoprene is a crucial non-methane biogenic volatile organic compound (BVOC) that exhibits the largest emissions globally. It is chemically reactive in the atmosphere and serves as the primary source of generating secondary organic aerosols (SOA) in terrestrial and remote marine regions. However, a comprehensive estimation of marine isoprene emissions is currently lacking. Here we built a module to present a 20-year (2001–2020) global hourly dataset for marine isoprene emissions, including phytoplankton-generated biological emissions (BIO emissions) and photochemistry-generated emissions in the sea surface microlayer (SML emissions) based on the latest advancements in biological, physical, and chemical processes, with high spatial resolutions. Our dataset suggests the annual global marine isoprene emissions amount to 1.097±0.009 Tg yr -1. Among these, the BIO emissions are 0.481±0.008 Tg yr -1 while SML emissions contribute 0.616±0.003 Tg yr -1. The ability of this module to estimate marine isoprene emissions was evaluated through comparison with a series of observations of marine isoprene concentrations and emission fluxes. The annual total isoprene emissions across the tropical ocean show a declining trend from 2001 to 2020. Most ocean regions exhibit a 1-year emission period, whereas a significant intraseasonal period is found in the tropical ocean. This dataset can be employed as input for the simulation of marine SOA formation in earth system models. This work provides the foundation for further studies into the impact of the air–sea system on marine SOA formation and its climate effect. The DOI link for the dataset is 10.11888/Atmos.tpdc.300521 (Cui and Zhu, 2023). [ABSTRACT FROM AUTHOR]

To investigate the prognostic value of N6-methyladenosine (m6A)-, 5-methylcytosine (m5C)-, and N1-methyladenosine (m1A)-related genes in cervical cancer (CESC) and predicting immunotherapy response. We downloaded cervical cancer mRNA expression profiles, clinical data, and m6A, m5C, m1A-related genes from public databases, and subjected them to serial bioinformatics analysis and clinical sample validation. Differential analysis revealed 106 methylation-related differential genes (MEDs), including 44 differentially downregulated and 62 upregulated genes. We then obtained methylation models containing 10 genes by univariate and multifactorial COX analysis. High risk genes with HR > 1 include IQGAP3, PTBP1, STAC3, CUX1, SLC2A1, and CA2, and low risk genes with HR < 1 include IGBP1, DUOX1, CHAF1A, and STAC3. We verified the accuracy of the model from inside TCGA and outside GSE39001 (AUC = 0.729). K-M analysis showed shorter survival times in the High-risk group, and Immunocytic infiltration analysis showed model genes closely associated with six immune cells. The high-risk group may benefit more effectively from immunosuppressive therapy, especially anti-CTLA-4 therapy (p <.05). We also screened nine drugs for potential treatment and verified the expression of three key genes SLC2A1, CUX1, and CA2 using immunohistochemistry and RT-qPCR experiments with clinical samples. We identified a prognostic model using m6A/m5C/m1A-related genes in cervical cancer, which can predict survival time and correlate with immune cell infiltration. Additionally, anti-CTLA-4 may be used as an immunotherapeutic agent for cervical cancer. Cervical cancer still has a high mortality rate, we aim to establish a strong prognostic index and new treatment goals for improving patient survival. The role of three types of RNA methylation modifications, m6A, m5C, and m1A, in cervical cancer, remains unknown. Therefore, it is essential to explore the potential molecular mechanisms of m6A, m5C, and m1A methylation regulation in cervical cancer. We also screened nine drugs for potential treatment and anti-CTLA-4 may be used as an immunotherapeutic agent for cervical cancer. We verified the expression of three key genes SLC2A1, CUX1, and CA2 [ABSTRACT FROM AUTHOR]

The sea‐land breeze (SLB) occurs regularly in coastal areas and influences the local climate and atmospheric environment. Fifteen‐year observations (2005–2019) from urban, coastal, and marine stations were collected to examine the trend in the number of SLB days (SLBD) in Tianjin, a coastal megacity in China. The number of SLBD in Tianjin generally showed a decreasing trend with an annual average decline rate of 3.89%. The average land breeze speed decreased by 0.20 m·s−1 and sea breeze speed decreased by 0.69 m·s−1 in the examined 15 years. Simultaneously, the distance of influence of SLB in summer was reduced by ∼30 km. The Weather Research and Forecasting model developed with high‐resolution land use data and variations in the sea surface temperature (SST) was applied to investigate the mechanisms leading to the weakening of SLB. The increasing SST led to a reduction in the temperature difference between sea and land, which was found to be the dominant factor driving the weakening of SLB in summer. The changes in the density and height of buildings due to urbanization altered the wind direction in the coastal areas, which in turn drive the reduction of the sea breeze during fall, while increased surface temperature at night in urban areas led to the reduction of the land breeze. With projections indicating ocean warming and increasing urbanization, the SLB will become weaker and occur less frequently in the future, probably leading to more frequent air pollution due to poor ventilation in coastal cities. Plain Language Summary: Sea‐land breeze (SLB) is one of the most common circulations over coastal areas and has a great impact on the local meteorology and atmospheric environment in coastal cities. Fifteen‐year observations in a Chinese costal megacity show a weakening trend of SLB with decreased occurring frequency and duration. Results from sensitivity experiments using developed regional weather model attribute the weakened SLB to the ocean warming and urbanization during examined 15 years. Urbanization would change the sea breeze direction, while ocean warming would decrease the temperature difference between the ocean and land during the daytime, thus suppressing the occurring of SLB. We are undergoing rapid urbanization and global warming so that SLB in the coastal cities are expected to be weakened in the future, which will possibly lead to inhospitable climate and air pollution. Key Points: Fifteen‐year observations indicate a weakening trend of sea‐land breeze (SLB) with decreased occurring frequency and duration in Tianjin, ChinaOcean warming leads the weakened SLB mainly in summer by reducing the temperature difference between the sea and landUrbanization is found to weaken the SLB mainly in fall and spring by changing the wind direction and urban heat island at night [ABSTRACT FROM AUTHOR]