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Maritime Power has gradually increased as a national strategy. In this process, gross marine products continue to grow, and the marine industry has become the most fundamental and critical object. The spatial layout and industrial organization of maritime enterprises are fundamental related tasks. Domestic research can be divided into two main categories, based on the data used. One is to use economic and social statistical data, which have a large spatial scope but large granularity and cannot reflect the details of the industrial layout. The other is to use point-of-interest data, which are often not fully mined owing to the heavy workload of data processing. Therefore, there is little relevant content on departmental and urban comparisons in the existing research. Four representative cities-Dalian, Qingdao, Ningbo, and Xiamen-were selected as the research areas. According to the Industrial Classification for Ocean Industries and Their Related Activities, the research objects were identified as the marine core layer, marine support layer, and marine peripheral layer industries and further refined into eight subcategories. This study is based on the information of maritime enterprises registered for business registration, and uses Python to crawl geographic coordinates to improve the spatial information of enterprises. An innovative task is to identify the industry categories of enterprises. This task was performed using fastText, Convolutional Neural Networks, and Recurrent Neural Network. Thus, a spatial enterprise information database, including multiple marine industry departments, was established. Kernel density analysis, standard deviational ellipse analysis, buffer analysis, and other methods were used. Finally, by comparing the visualization results of the marine industrial spatial layout in the four cities, we delved into the marine industrial spatial differentiation patterns. In the experiment, machine learning models, such as artificial neural networks, exhibited high accuracy and recall when completing human recognition tasks, and these methods were effective. Empirical research on the spatial layout and industrial organization of maritime enterprises revealed the following: 1)From the perspective of spatial pattern, the overall pattern is a balanced pattern of "large dispersion and small agglomeration." By comparing the distribution and organization of different types of marine industries, we found that there is industry agglomeration in the location selection of enterprises, resulting in industry agglomeration characteristics. The land sea relationship is reflected in the high-density single peak or "coastal zone-city center" Multimodal distribution pattern. 2) From the perspective of spatial organization mode, industrial clusters have multilevel hierarchical characteristics corresponding to population size and administrative levels. In addition to single core structures, multi core structures generally exhibit a "primary-secondary dual core" or "primary core-multiple radial" pattern, with spatial connections between core intervals forming a multi node axis or network structure. 3) From the perspective of spatial matching relationships, the elliptical area is positively related to the urban area, the direction of the long axis is close to the coastal direction, and the industrial distribution has a clear matching relationship with the urban center, ports, and other transportation hubs, bay terrain, coastline, and other spatial elements.

The deep shale gas in the Fuling area is characterized by complex structures, high crustal stress, significant stress differences, high formation temperatures, high compaction levels, low porosity, low permeability, and complex porosity-permeability variation patterns. One reason for the significant production differences between wells is the insufficient understanding of the geomechanical features and controlling mechanisms of deep shale gas reservoirs, and the inaccurate identification of sweet spots for hydraulic fracturing. This study focuses on the marine shale of the Wufeng-Longmaxi formations in the Fuling area, investigating the micromechanical characteristics and controlling mechanisms of deep shale gas reservoirs through five series of experiments: micro rock mechanics experiments, digital speckle experiments, X-ray diffraction, total organic carbon content measurement, and scanning electron microscopy (SEM). Coupled with digital image processing technology, the changes in stress field and displacement field, and microcrack propagation processes in the Longmaxi shale under loading conditions were meticulously depicted. The deformation and fracture characteristics of the Longmaxi shale were analyzed. Experimental results indicated that the total organic carbon content in the deep shale is approximately 4.2%, with quartz content at 55.4% and clay mineral at 26.9%. The study identified five stages of microdamage evolution in deep shale: compaction, elasticity, uniform crack propagation, crack propagation failure, and brittle failure. Under the influence of brittle minerals such as quartz, and soft components such as organic matter, the microcracks in deep shale exhibit various propagation modes, including transgranular, intergranular, and laminated layer cracks. Additionally, the fracture toughness indices of the deep shale samples were calculated, with Mode Ⅰ index being 8.279 $\mathrm{MPa} \cdot \sqrt{\mathrm{m}}$ and Mode Ⅱ index being 1.243 $\mathrm{MPa} \cdot \sqrt{\mathrm{m}}$. These experimentally obtained fracture toughness indices can be applied to evaluate the brittleness of deep shale, providing guidance for deep shale fracturing modification.

Objective Aiming at the insufficient control indexes for high-speed railway subgrade horizontal deformation currently, it is necessary to study the influence law and limit values of ballastless track subgrade horizontal deformation. Method Using finite element method, the structural stress, deformation, and track irregularity of CRTS (China railway track system) II type ballastless track are calculated under horizontal deformation conditions of cosine-shaped subgrade with different wavelengths and amplitudes. Referring to the allowable tolerance values for track geometric dimensions and the allowable tensile stress values of ballastless track structure, the transmission law and limit values of subgrade cosine-shaped horizontal deformation are studied. Result & Conclusion The horizontal deformation of ballastless track structures such as rail, track slab, mortar layer and supporting layer shows significant response characteristics to cosine-shaped horizontal deformation of high-speed railway subgrade. When the wavelength and amplitude of horizontal deformation are 20 m and 10 mm respectively, the influence of subgrade cosine-shaped horizontal deformation on track alignment irregularity is the greatest, followed by the influence on track horizontal irregularity, while the influence on gauge and vertical irregularity indicators can be ignored. When the amplitude of horizontal deformation is 20 mm, as its wavelength increases, the maximum value of rail horizontal deformation increases, while the track irregularity, track slab and supporting layer tensile stresses first increase and then decrease. The limit value of subgrade cosine-shaped horizontal deformation amplitude increases with the increase of horizontal deformation wavelength, and the two satisfy a quadratic function relationship.

Abstract To systematically analyze the damage caused by bedrock and overburden layer slope under seismic action, a set of large-scale shaking table test was designed and completed. Interpolation of the acceleration amplification coefficient, Hilbert–Huang transform and transfer function was adopted. The damage mechanisms of the bedrock and overburden layer slopes under seismic action are systematically summarized in terms of slope displacement, acceleration field, vibration amplitude, energy, vibration frequency, and damage level. The results show a significant acceleration amplification effect within the slope under seismic action and a localized amplification effect at the top and trailing edges of the slope. With an increase in the input seismic intensity, the difference in the vibration amplitude between the overburden layer and bedrock increased, low-frequency energy of the overburden layer was higher than that of the bedrock, and the vibration frequency of the overburden layer was smaller than that of the bedrock. These differences cause the interface to experience cyclic loading continuously, resulting in the damage degree of the overburden layer at the interface being larger than that of the bedrock, reduction of the shear strength, and eventual formation of landslides. The displacement in the middle of the overburden is always greater than that at the top. Therefore, under the action of an earthquake and gravity, the damage mode of the bedrock and overburden layer slope is such that the leading edge of the critical part pulls and slides at the trailing edge, and multiple tensile cracks are formed on the slope surface.

Abstract Lysine crotonylation (Kcr) is a recently discovered histone acylation modification that is closely associated with gene expression, cell proliferation, and the maintenance of stem cell pluripotency and indicates the transcriptional activity of genes and the regulation of various biological processes. During cell culture, the introduction of exogenous croconic acid disodium salt (Nacr) has been shown to modulate intracellular Kcr levels. Although research on Kcr has increased, its role in cell growth and proliferation and its potential regulatory mechanisms remain unclear compared to those of histone methylation and acetylation. Our investigation demonstrated that the addition of 5 mM Nacr to cultured bovine fibroblasts increased the expression of genes associated with Kcr modification, ultimately promoting cell growth and stimulating cell proliferation. Somatic cell nuclear transfer of donor cells cultured in 5 mM Nacr resulted in 38.1% blastocyst development, which was significantly greater than that in the control group (25.2%). This research is important for elucidating the crotonylation modification mechanism in fibroblast proliferation to promote the efficacy of somatic cell nuclear transfer.

Objective To explore the correlation between the expression of long non-coding RNA(lncRNA) UCA1 and radiotherapy sensitivity in patients with esophageal squamous cell carcinoma. Methods A total of 80 patients with esophageal squamous cell carcinoma admitted to the Affiliated Tumor Hospital of Xinjiang Medical University from February 2020 to February 2022 were selected as the esophageal cancer group, and 50 subjects who underwent health examinations in our hospital during the same period were selected as the control group.Real time fluorescence quantitative PCR was used to detect the plasma lncRNA UCA1 expression levels of all subjects and compare them.The relationship between lncRNA UCA1 levels and clinical pathological indicators in esophageal cancer patients, as well as their relationship with radiation sensitivity, was analyzed. Results The plasma lncRNA UCA1 levels in the esophageal cancer group were higher than those in the control group, and the difference was statistically significant(P0.05);The plasma lncRNA UCA1 levels in patients with TNM stage Ⅲ+Ⅳ esophageal squamous cell carcinoma were higher than those in patients with stage Ⅰ+Ⅱ, and the difference was statistically significant(P2.31) showed a significant decrease in radiotherapy sensitivity(P

Abstract In the realm of photovoltaics, organometallic hybridized perovskite solar cells (PSCs) stand out as promising contenders for achieving high‐efficiency photoelectric conversion, owing to their remarkable performance attributes. Nevertheless, defects within the perovskite layer, especially at the perovskite grain boundaries and surface, have a substantial impact on both the overall photoelectric performance and long‐term operational stability of PSCs. To mitigate this challenge, we propose a method for water‐induced condensation polymerization of small molecules involving the incorporation of 1,3‐phenylene diisocyanate (1,3‐PDI) into the perovskite film using an antisolvent technique. Subsequent to this step, the introduction of water triggers the polymerization of [P(1,3‐PDI)], thereby facilitating the in situ passivation of uncoordinated lead defects inherent in the perovskite film. This passivation process demonstrates a notable enhancement in both the efficiency and stability of PSCs. This approach has led to the attainment of a noteworthy power conversion efficiency (PCE) of 24.66% in inverted PSCs. Furthermore, based on the P(1,3‐PDI) modification, these devices maintain 90.15% of their initial efficiency after 5000 h of storage under ambient conditions of 25°C and 50 ± 5% relative humidity. Additionally, even after maximum power point tracking for 1000 h, the PSCs modified with P(1,3‐PDI) sustain 82.05% of the initial PCE. Small molecules can rationally manipulate water and turn harm into benefit, providing new directions and methods for improving the efficiency and stability of PSCs.

Precipitation strengthening is a key strengthening method for metallic materials. However, the temperature effect on precipitation strengthening is still unclear to date. Based on dislocation theory, a thermally-activated precipitation strengthening model is built by considering the competition between shear and bypass mechanisms. For medium-sized precipitate particles, the thermally-activated shear mechanism dominates the precipitation strengthening, resulting in a plateau region. While, for large or very fine precipitate particles, the thermally-activated bypass mechanism dominates the precipitation strengthening, leading to the strengthening or weakening regions. Moreover, the effects of precipitate phase volume fraction, temperature, shear modulus, strain rate, and mobile dislocation density on precipitation strengthening are also investigated. This study not only provides new insights into precipitation strengthening from the perspective of thermal activation but also offers clear guidance for the design of new materials.

Under the repeated action of residual stress and wheel load caused by welding, fatigue cracks easily occur on the top plate-U rib welding of an orthotropic bridge deck (OBD). These affect the service life. To study the influence of different full-penetration welding methods on the residual stress and fatigue of OBD, this study compared the residual stress, welding deformation, and fatigue performance of full-penetration single- and double-sided welding through finite element analysis. The welding temperature and residual stress fields were simulated based on Goldak's double ellipsoid heat source model using the thermal elastic-plastic method. The numerical results were verified using measured data from relevant literature, and the two were in good agreement. The results showed that the longitudinal residual stress of the double-sided welded U-rib was larger than that of the single-sided welded U-rib, primarily in the compressive stress range, and the maximum deviation reached 99.44 MPa. The longitudinal displacement of single-sided welding along the weld direction was 0.060 mm lesser than that of double-sided welding, and the maximum vertical displacement perpendicular to the weld direction was 2.457 mm lesser than that of double-sided welding. For the same frequency of fatigue load (wheel load), the fatigue strength of single-sided welding was larger than that of double-sided welding, and the fatigue life increased by 29.7%. In this study, analysis models of the full-penetration single-sided and full-penetration double-sided welding were established, which could provide a reference for structural fatigue assessment using the two full-penetration welding techniques under the influence of residual stress.

An efficient method was discovered for catalyzing the esterification under air using Novozym 435 to obtain pyridine esters. The following conditions were found to be optimal: 60 mg of Novozyme 435, 5.0 mL of n-hexane, a molar ratio of 2:1 for nicotinic acids (0.4 mmol) to alcohols (0.2 mmol), 0.25 g of molecular sieve 3A, a revolution speed of 150 rpm, a reaction temperature of 50 °C, and reaction time of 48 h. Under nine cycles of Novozym 435, the 80 % yield was consistently obtained. Optimum conditions were used to synthesize 23 pyridine esters, including five novel compounds. Among them, gas chromatography-mass spectrometry-olfactometry (GC-MS-O) showed phenethyl nicotinate (3g), (E)-hex-4-en-1-yl nicotinate (3m), and octyl nicotinate (3n) possessed strong aromas. Thermogravimetric analysis (TG) revealed that the compounds 3g, 3m and 3n exhibited stability at the specified temperature. This finding provides theoretical support for adding pyridine esters fragrance to high-temperature processed food.

Abstract After undergoing metabolic reprogramming, tumor cells consume additional glutamine to produce amino acids, nucleotides, fatty acids, and other substances to facilitate their unlimited proliferation. As such, the metabolism of glutamine is intricately linked to the survival and progression of cancer cells. Consequently, targeting the glutamine metabolism presents a promising strategy to inhibit growth of tumor cell and cancer development. This review describes glutamine uptake, metabolism, and transport in tumor cells and its pivotal role in biosynthesis of amino acids, fatty acids, nucleotides, and more. Furthermore, we have also summarized the impact of oncogenes like C-MYC, KRAS, HIF, and p53 on the regulation of glutamine metabolism and the mechanisms through which glutamine triggers mTORC1 activation. In addition, role of different anti-cancer agents in targeting glutamine metabolism has been described and their prospective applications are assessed.

Abstract Ancient whole-genome duplication (WGD) or polyploidization is prevalent in plants and has played a crucial role in plant adaptation. However, the underlying genomic basis of ecological adaptation and subsequent diversification after WGD are still poorly understood in most plants. Here, we report a chromosome-scale genome assembly for the genus Orinus (Orinus kokonorica as representative) and preform comparative genomics with its closely related genus Cleistogenes (Cleistogenes songorica as representative), both belonging to a newly named subtribe Orininae of the grass subfamily Chloridoideae. The two genera may share one paleo-allotetraploidy event before 10 million years ago, and the two subgenomes of O. kokonorica display neither fractionation bias nor global homoeolog expression dominance. We find substantial genome rearrangements and extensive structural variations (SVs) between the two species. With comparative transcriptomics, we demonstrate that functional innovations of orthologous genes may have played an important role in promoting adaptive evolution and diversification of the two genera after polyploidization. In addition, copy number variations and extensive SVs between orthologs of flower and rhizome related genes may contribute to the morphological differences between the two genera. Our results provide new insights into the adaptive evolution and subsequent diversification of the two genera after polyploidization.

Coilia nasus is a species of anadromous migratory fish, which predominantly lives in the sea. During the breeding season, the reproductive population migrates from the sea to rivers to reproduce and clusters to form a fishing season. The Yangtze Estuary is an important migration channel for this species. In recent years, due to the influence of upstream dam construction, water conservancy projects along the Yangtze River, environmental pollution and overfishing, the populations of this species in the Yangtze River are on the verge of extinction. In order to better protect C. nasus in the Yangtze River, a large number of studies on the conservation and management of its resources, migration habits, genetic structure, and the effects of resource recovery on this species have been conducted. As for the nutritional composition of C. nasus, studies have been conducted on the different sources, ecotypes, breeding methods, and stages of gonad development. These studies have mainly focused on the muscle nutrition of C. nasus from the Yangtze River; however, none have investigated the nutritional composition of different tissues of the reproductive populations from the Yangtze Estuary. This study is the first to determine the nutritional status of the reproductive population that migrates to the Yangtze Estuary with mature ovaries, and to compare and analyze the distribution characteristics of total lipids and fatty acids in different tissues, and provides reference information for ascertaining the nutritional status and reproductive performance of this species in the Yangtze Estuary. In this study, the contents of moisture, total lipid, and fatty acid composition in muscle, liver, and ovary tissues of adult female C. nasus with gonad development stage Ⅳ were measured and analyzed using standard GB methods. The results indicated that: The moisture content declined successively in muscle, liver, and ovary tissues, with measurements of (77.91±1.61)%, (75.01±1.33)%, and (46.77±5.58)%, respectively. The total lipid content of dry matter increased successively in muscle, liver, and ovary tissues, with measurements of (16.21±1.09)%, (21.94±1.23)%, and (55.21±1.35)%, respectively. The saturated fatty acids (SFA) content was (29.89±0.81)%, (37.60±3.06)%, and (18.33±1.61)% in the muscle, liver, and ovaries, respectively, with the highest in the liver and the lowest in the ovaries. There were significant differences in SFA contents among the three tissues (P0.05). The ratio of UFA/SFA in muscle, liver, and ovary tissues was 2.35, 1.67, and 4.49, respectively, and the ratio of n3-PUFA/n6-PUFA in the same three tissues was 4.94, 3.87, and 5.13, respectively. These ratios were highest in the ovary, followed by the muscle, and were the lowest in the liver. In summary, the total lipid, PUFA, EPA, DHA, and n3-PUFA contents and the ratios of UFA/SFA and n3-PUFA/n6-PUFA were highest in ovary tissues, and the distribution characteristics of the corresponding composition in different tissues was closely related to the reproductive habits of this species during gonad development stage Ⅳ. The accumulation of rich lipids and reasonable essential fatty acid nutrition in the ovary can improve the reproductive performance of C. nasus in this stage and provide sufficient nutrition and energy sources for the development of eggs and larvae in the subsequent stage. In this study, it was found that the lipid and polyunsaturated fatty acid nutrition of C. nasus adults with ovarian development to stage Ⅳ selectively accumulated in the ovary, which is an adaptation to the reproductive activities of this species at this stage. The results provide basic data for determining the differences in nutritional demands of C. nasus adults at different ovarian development stages and the mechanisms for the synthesis and transformation of essential fatty acids. Additionally, this study lays a foundation for further exploration of the relationship between ovarian nutritional status and egg quality. Relevant data can enrich the reproductive biology knowledge of this species and provide theoretical guidance for protecting the reproductive population and the maintenance of C. nasus spawning grounds in the waters adjacent to the Yangtze Estuary.

Abstract Fish dietary niche is a core focus, and it reflects the diversity of resources, habitats, or environments occupied by a species. However, whether geographic segregation among different populations triggers dietary diversification and concomitant fish niche shift remains unknown. In the present study, we selected the Black Amur bream (Megalobrama terminalis) is a migratory fish species that plays an important role in the material transfer and energy cycling of river ecosystems, inhabiting southern China drainage with multiple geographic populations. Here, we utilized the combined analyses of 18S rDNA high‐throughput sequencing in fish gut contents and fatty acid (FA) in muscle tissues to evaluate potential spatial patterns of habitat and resource use for M. terminalis in three rivers of southern China. Our results showed that prey items of the Xijiang (XR) population (Pearl River) exhibited the highest species diversity and richness among the three geographic populations. Moreover, diet composition of M. terminalis was affected by spatial differences associated with geographic segregation. Analyses of FA biomarkers indicated that the highest levels of C16:0, C18:3n‐3, and C18:2n‐6c were found in Wanquan (WS) population (Wanquan River). The XR population exhibited a distinct FA profile characterized by higher amounts of arachidonic acid (ARA) and docosahexaenoic acid (DHA). The Moyang (MY) population (Moyang River) acted as the linkage between WS and XR populations and consisted of middle levels of saturated FAs (SFAs) and polyunsaturated FAs (PUFAs). The XR population displayed a greater FA niche width compared with WS population. Furthermore, we observed a close positive relationship between the niche width and α‐diversity indices of dietary resources for FA proflies. Our study provides valued information to develop different conservation strategies among different populations and improve fisheries management for M. terminalis and other endemic species in local rivers.