A method for estimating particulate organic carbon at the sea surface based on geodetector and machine learning

Particulate organic carbon (POC) is an essential component of the carbon pump within marine organisms. Exploring estimation methods for POC holds substantial significance for understanding the marine carbon cycle. In this study, we investigated the spatial heterogeneity of 30 factors and POC concentrations using geodetector to account for nonlinearity, diversity, and complexity. Ultimately, 20 factors including sea surface temperature, sea surface salinity, and chlorophyll-a were selected as modeling variables. Six machine learning models—backpropagation neural network, convolutional neural network, attention-based neural network, random forest (RF), adaptive boosting, and extreme gradient boosting were used to compare their performance. The results indicate that among the six machine learning algorithms, RF exhibits the strongest performance, with a root mean square error of 0.11 [log(mg/m3)] and an average percentage deviation of 2.73%. Global annual average sea surface POC concentrations were estimated for 2007 and compared to NASA’s POC product. The outcomes indicate that the RF model-based estimation method displays enhanced accuracy in estimating POC concentrations within intricate coastal environments, while the backpropagation neural network performed better in estimating POC concentrations in open ocean areas. Leveraging the RF model, global sea surface POC concentrations were estimated for the years 2007 through 2016, enabling a spatiotemporal analysis. The analysis unveils heightened POC concentrations in coastal regions and lower levels in open ocean areas. Furthermore, POC concentrations were greater in high-latitude regions compared to mid and low latitude counterparts. In conclusion, the global sea surface POC product in this study exhibits heightened spatial resolution and improved data completeness in contrast to other products. It enhances the accuracy of conventional POC estimation methods, particularly within coastal regions

A Study of the Regional Vocational Training Efficiency of Migrant Workers

Based on DEA-Tobit model, the efficiency of occupational training for rural migrant workers of 30 provinces and cities was studied in this paper. The results indicated that there are significant differences among these 30 provinces and cities. Technical efficiency of East areas is lower than average level. Moreover, there is a significant negative correlation between the efficiency and Average education attainment, and a significant positive correlation between the efficiency and proportion of rural population

Application of engineering- R&D integrated thinking mode for innovative talents cultivation of intelligent navigation experimental class

In view of the four prominent contradictions in the traditional engineering thinking teaching system of surveying and mapping engineering, which are difficult to meet the new requirements of innovative talents cultivation, a new talent training mode based on the integration of engineering and re-search thinking is proposed. Taking surveying and mapping engineering (intelligent navigation experimental class) as the research object, the multi-level training system of “thinking transformation - professional development - model transformation” was designed, and the reform and practice were carried out from the multiple links of “curriculum system - textbook construction - practical teaching - innovation credits”. The teaching practice in the past four years shows that the integrated thinking mode of engineering and research has been well applied in the cultivation of innovative talents in the intelligent navigation experimental class, and has achieved remarkable results in many aspects, such as the improvement of innovation ability, the promotion of teaching and practice system, the construction and application of teaching materials, and the development of disciplines and specialties, laying a solid foundation for the output of top innovative talents in the intelligent navigation experimental class

A path to human‐raccoon dog harmony: Identifying factors influencing the tolerance of urban residents in Shanghai towards a neglected species

Abstract Human‐wildlife interactions become increasingly common in urban areas across all continents and ecosystem types. Depending on the context, human‐wildlife interactions can be categorized as harmonious, neutrality, or in conflict and raises cultural, economic and ecological challenges in maintaining urban biodiversity. Understanding the mechanism behind the tolerance of residents to the presence of wildlife is vital to promoting a harmonious coexistence between humans and wildlife in urban environments. To advance our knowledge of this mechanism, we developed a questionnaire to survey residents in Shanghai, China about their knowledge of and attitude towards raccoon dogs (Nyctereutes procyonoides), a species whose population is increasing in urban areas. Using 281 questionnaires, we conducted structural equation modelling to examine how relational values, including familiarity with raccoon dogs, perceived benefits and risks, together with residents' trust in wildlife management authorities, interactively influence the tolerance for this species. We found that the residents' familiarity with raccoon dogs positively influenced their tolerance, both directly and indirectly through increased perceived benefits and reduced perceived risks. Furthermore, trust in wildlife management authorities contributed to higher tolerance through perceived benefits. Our results suggested that education about the relational values of raccoon dogs to the public can reduce the traditional negative connotation for this species and promote the coexistence of people and raccoon dogs in Shanghai urban environment. Based on our understanding about how raccoon dogs were culturally constructed and the willingness of residents to share landscapes with the species, we advocate that relational values play an important role in future urban biodiversity conservation planning. We also advocate for education programs that familiarize the public with raccoon dogs as well as other species, which can turn urban human‐wildlife conflicts into harmonious relationships in Shanghai and other urban areas. Read the free Plain Language Summary for this article on the Journal blog

Ultradeep Lysine Crotonylome Reveals the Crotonylation Enhancement on Both Histones and Nonhistone Proteins by SAHA Treatment

Lysine crotonylation is a newly discovered protein post-translational modification and was reported to share transferases and deacylases with lysine acetylation. The acetyltransferase p300 was reported to also contain crotonyltransferase activity, and class I histone deacetylases were demonstrated to be the major histone decrotonylases. However, the decrotonylases for nonhistone proteins are unclear. Moreover, because of the lack of high-quality pan-antibodies, large-scale analysis of crotonylome still remains a challenge. In this work, we comprehensively studied lysine crotonylome on both histones and nonhistone proteins upon SAHA treatment and dramatically identified 10 163 lysine crotonylation sites in A549 cells. This is the first identification of tens of thousands of lysine crotonylation sites and also the largest lysine crotonylome data set up to now. Moreover, a parallel-reaction-monitoring-based experiment was performed for validation, which presented highly consistent results with the SILAC experiments. By intensive bioinformatic analysis, it was found that lysine crotonylation participates in a wide range of biological functions and processes. More importantly, it was revealed that both the crotonylation and acetylation levels of most core histones sites and a number of nonhistone proteins as well as some known substrates of class IIa and IIb HDACs were up-regulated after SAHA treatment. These results suggest that SAHA may have decrotonylation inhibitory activities on both histones and nonhistone proteins by inhibiting HDACs

Ultradeep Lysine Crotonylome Reveals the Crotonylation Enhancement on Both Histones and Nonhistone Proteins by SAHA Treatment

Lysine crotonylation is a newly discovered protein post-translational modification and was reported to share transferases and deacylases with lysine acetylation. The acetyltransferase p300 was reported to also contain crotonyltransferase activity, and class I histone deacetylases were demonstrated to be the major histone decrotonylases. However, the decrotonylases for nonhistone proteins are unclear. Moreover, because of the lack of high-quality pan-antibodies, large-scale analysis of crotonylome still remains a challenge. In this work, we comprehensively studied lysine crotonylome on both histones and nonhistone proteins upon SAHA treatment and dramatically identified 10 163 lysine crotonylation sites in A549 cells. This is the first identification of tens of thousands of lysine crotonylation sites and also the largest lysine crotonylome data set up to now. Moreover, a parallel-reaction-monitoring-based experiment was performed for validation, which presented highly consistent results with the SILAC experiments. By intensive bioinformatic analysis, it was found that lysine crotonylation participates in a wide range of biological functions and processes. More importantly, it was revealed that both the crotonylation and acetylation levels of most core histones sites and a number of nonhistone proteins as well as some known substrates of class IIa and IIb HDACs were up-regulated after SAHA treatment. These results suggest that SAHA may have decrotonylation inhibitory activities on both histones and nonhistone proteins by inhibiting HDACs

Strong terahertz absorption of monolayer graphene embedded into a microcavity

Terahertz reflection behaviors of metallic-grating-dielectric-metal (MGDM) microcavity with a monolayer graphene embedded into the dielectric layer are theoretically investigated. A tunable wideband reflection dip at about the Fabry–Pérot resonant frequency of the structure is found. The reflectance at the dip frequency can be electrically tuned in the range of 96.5% and 8.8%. Because of the subwavelength distance between the metallic grating and the monolayer graphene, both of the evanescent grating slit waveguide modes and the evanescent Rayleigh modes play key roles in the strong absorption by the graphene layer. The dependence of reflection behaviors on the carrier scattering rate of graphene is analyzed. A prototype MGDM-graphene structure is fabricated to verify the theoretical analysis. Our investigations are helpful for the developments of electrically controlled terahertz modulators, switches, and reconfigurable antennas based on the MGDM-graphene structures