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Domestic research on the planning of the Tokyo metropolitan area of Japan mainly includes evaluation and comparative research. The former involves the perspectives of planning interpretation, experience summarization, and history evolution; the latter compares and analyzes the three major urban agglomerations in China against the Tokyo metropolitan area. On the whole, most evaluation studies focus on the metropolitan area planning itself, and rarely focus on that of each prefecture and county under the metropolitan area. The relationship between these lower-level and metropolitan area planning has received relatively little attention. Comparative studies mostly cover various fields such as economy, industry, environmental protection, and so on, but the discussion paradigm is generally based on "introduction to the current situation → inspiration and reference," with rare objective comparison made under a reasonable benchmark and appropriate framework. At the same time, comparative research on urban agglomeration planning itself is also uncommon. As important spatial representations of the economic development in China and Japan, with what important planning has the Tokyo Bay Area (TBA) and the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) developed to date? How do these plans relate to each other? What are the characteristics and differences? What results did these similarities and differences ultimately lead to? Answering these questions is not only related to the construction effectiveness of the GBA itself, but also has certain significance for other urban agglomerations in China. In this context, we adopt "development" and "space" as the two perspectives to analyze the planning system of the two major bay areas from the aspects of planning property, background, target area, goal, regional positioning, and main measures. On this basis, the similarities and differences between the two are summarized in six aspects: historical background and relevant system, departmental and institutional system, vertical transmission mechanism, horizontal coordination mechanism, planning system characteristics and public participation. This study argues that the following: (1) The two bay areas have played leading roles in industrialization, urban system construction, and urban agglomeration planning system construction in each country, but there are differences in the historical backgrounds and relevant social systems. (2) Under the decentralization of powers, the setting and naming of departments and institutions of TBA are relatively flexible, and they participate in the preparation process of comprehensive planning in the form of "Council." Except for Hong Kong and Macao, the departmental settings of GBA are orderly, clear, and consistent in form. (3) In terms of vertical transmission system, the central-level planning of TBA is self-contained and continuous but that at the county-level is relatively free, and the upper-level planning is not absolutely mandatory; the relationship between the upper and lower levels of GBA-related planning is relatively clear but that at the regional-level has some flexibility in execution. (4) In the horizontal coordination system, the TBA has established two major joint meeting systems to coordinate regional governance and planning formulation, while planning has weakened the positioning to each city's functions. Furthermore, GBA has also established cooperation mechanisms with different levels of cooperation for various issues, and the characteristics of planning for the positioning of urban functions are still obvious. (5) In terms of planning nature, the developmental and spatial planning of TBA have been combined into comprehensive planning, and the spatial aspect has obvious characteristics of stock planning. GBA still formulates planning from three aspects of development, space, and urban and rural areas and is in the transition from incremental to stock planning. (6) In terms of public participation, TBA has broken through the traditional planning paradigm and has begun to involve micro-fields such as personal value, with a high degree of public participation. In recent years, GBA has continuously enriched the planning content and has also made progress in the construction of public participation mechanisms and awareness training, but there is still room for improvement.

When a high-speed train is parallel with a pipeline, its power supply system provokes alternating current (AC) interference that results in the corrosion of the pipeline and a risk of electric shock to pipeline workers. Because trains are continuously moving, the AC interference on the pipeline changes, making mitigation design difficult. In this study, we used numerical simulation to study how the location of a high-speed train influences a pipeline. The results revealed the following: (1) AC interference on a pipeline mainly depends on the current in the rail, because a large amount of current leaks from the rail to the earth, generating a current imbalance. (2) While a train is running from TPSS to AT2, AC voltage peaks appear at the beginning, the ending of the parallel segment, and the middle of each AT section; therefore, the mitigating measurement, if needed, should be the priority at these positions. (3) Compared to the interference caused by a single train, the interference on pipeline is not doubled, but only increases slightly. Moreover, interference reaches its maximum not when two trains are at 5 and 15 km, but when they are at AT1 and 15 km. (4) Field testing was conducted on an actual gas pipeline in the Beijing area. The results showed that the field-tested AC voltage of the pipeline was generally consistent with the calculations. [ABSTRACT FROM AUTHOR]

To access degradable polyolefin plastic, non‐alternating copolymerization of ethylene (E) and carbon monoxide (CO) for producing polyethylene (PE) with in‐chain ketones is particularly appealing; however, it still presents significant challenges such as molecular weight modulation (hydrogen response) and chain endgroup control (functional terminal). In this study, we achieved hydrogen‐controlled E/CO non‐alternating copolymerization using late transition metal catalysts. This process results in linear PEs containing the desired non‐alternating in‐chain keto groups (1.0–9.3 mol %) and with tunable molecular weights ranging from 43 to 195 kDa. In this reaction, H2 serves as a chain transfer agent, modulating the polymer's molecular weight, forming unique aldehyde endgroups and eliminating usual olefinic endgroups; CO undergoes non‐alternating insertion into the PE chain, resulting in a strictly non‐alternating structure (>99 %) for the keto‐PE. The dispersed incorporation of in‐chain keto groups retains bulk properties of PE and makes PE susceptible to photodegradation, which produces significantly lower molecular weight polymers and oligomers with unambiguous vinyl and acetyl terminals. [ABSTRACT FROM AUTHOR]

The unscientific application of nitrogen (N) fertilizer not only increases the economic input of pear growers but also leads to environmental pollution. Improving plant N use efficiency (NUE) is the most effective economical method to solve the above problems. The absorption and utilization of N by plants is a complicated process. Glutamine synthetase (GS) and glutamate synthase (GOGAT) are crucial for synthesizing glutamate from ammonium in plants. However, their gene family in pears has not been documented. This study identified 29 genes belonging to the GS and GOGAT family in the genomes of Pyrus betulaefolia (P.be, 10 genes), Pyrus pyrifolia (P.py, 9 genes), and Pyrus bretschneideri (P.br, 10 genes). These genes were classified into two GS subgroups (GS1 and GS2) and two GOGAT subgroups (Fd–GOGAT and NADH–GOGAT). The similar exon–intron structures and conserved motifs within each cluster suggest the evolutionary conservation of these genes. Meanwhile, segmental duplication has driven the expansion and evolution of the GS and GOGAT gene families in pear. The tissue–specific expression dynamics of PbeGS and PbeGOGAT genes suggest significant roles in pear growth and development. Cis–acting elements of the GS and GOGAT gene promoters are crucial for plant development, hormonal responses, and stress reactions. Furthermore, qRT–PCR analysis indicated that PbeGSs and PbeGOGATs showed differential expression under exogenous hormones (GA3, IAA, SA, ABA) and abiotic stress (NO3− and salt stress). In which, the expression of PbeGS2.2 was up–regulated under hormone treatment and down–regulated under salt stress. Furthermore, physiological experiments demonstrated that GA3 and IAA promoted GS, Fd–GOGAT, and NADH–GOGAT enzyme activities, as well as the N content. Correlation analysis revealed a significant positive relationship between PbeGS1.1, PbeGS2.2, PbeNADH–GOGATs, and the N content. Therefore, PbeGS1.1, PbeGS2.2, and PbeNADH–GOGATs could be key candidate genes for improving NUE under plant hormone and abiotic stress response. To the best of our knowledge, our study provides valuable biological information about the GS and GOGAT family in the pear for the first time and establishes a foundation for molecular breeding aimed at developing high NUE pear rootstocks. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding the genetics behind the reproductive traits of pigs is crucial for enhancing productivity and economic outcomes in the pork industry. In this study, we investigated the genetic factors influencing reproductive characteristics in Large White pigs. By analyzing the genetic data of 2237 sows from southern China, we identified specific genes and genetic markers associated with important reproductive traits, such as litter size. Our findings provide valuable insights that could help in developing targeted breeding strategies aimed at improving these traits. This research is not only significant for farmers and breeders but also contributes to a more sustainable and efficient approach to pig farming. (1) Background: Reproductive performance is crucial for the pork industry's success. The Large White pig is central to this, yet the genetic factors influencing its reproductive traits are not well understood, highlighting the need for further research. (2) Methods: This study utilized Genome-Wide Association Studies to explore the genetic basis of reproductive traits in the Large White pig. We collected data from 2237 Large White sows across four breeding herds in southern China, focusing on eight reproductive traits. Statistical analyses included principal component analysis, linkage disequilibrium analysis, and univariate linear mixed models to identify significant single-nucleotide polymorphisms and candidate genes. (3) Results: Forty-five significantly related SNPs and 17 potential candidate genes associated with litter traits were identified. Individuals with the TT genotype at SNP rs341909772 showed an increase of 1.24 in the number of piglets born alive (NBA) and 1.25 in the number of healthy births (NHBs) compared with those with the CC genotype. (4) Conclusions: The SNPs and genes identified in this study offer insights into the genetics of reproductive traits in the Large White pig, potentially guiding the development of breeding strategies to improve litter size. [ABSTRACT FROM AUTHOR]

Vascular hyporesponsiveness in the shock decompensation period is an important factor leading to death. Myosin light chain 20 (MLC20) is the main effector protein that regulates vascular reactivity. However, whether the change in semicarbazide-sensitive amine oxidase (SSAO) expression during hypoxia can change the MLC20 phosphorylation level, and its underlying mechanism were not clear. The amine oxidase copper containing 3 (AOC3) overexpressing adenovirus vector was constructed and transfected into rat intestinal microvascular endothelial cells (RIMECs) to overexpress SSAO, and the RIMECs were co-cultured with rat intestinal microvascular smooth muscle cells (RIMSCs). The changes in SSAO/inducible nitric oxide synthase (iNOS)/Rho associate coiled-coil containing protein kinase 1 (ROCK1) expression levels and MLC20 phosphorylation level were detected. Here we found that the increased SSAO by AOC3 overexpression can decrease the iNOS expression level and its activity after hypoxia. In addition, RIMSCs co-cultured with RIMECs overexpressed with AOC3 gene had significantly higher ROCK1 protein level and MLC20 phosphorylation level than RIMSCs co-cultured with normal RIMECs. Our study demonstrated that SSAO overexpression can significantly inhibit iNOS activity, promote RhoA/ROCK pathway activation, and increase the phosphorylation level of MLC20, which might be the potential mechanism in relieving the vascular hyporesponsiveness during shock decompensation.

AbstractTo examine CFST short columns’ mechanical properties under extreme temps, 14 specimens were designed, focusing on temp’s impact on materials. Axial compression tests revealed temp-dependent changes: concrete strength surged at low temps but ductility diminished, while steel’s properties stayed stable. Concrete strength gains boosted columns’ strength, enhancing steel-concrete synergy. Shear failure dominated at low temps. Ductility improved with thinner diameters or wetter mixes. Calculations underestimated actual capacity, likely due to temperature neglect in design codes, EC4 most notably. Finally, incorporating the experimental results, the bearing capacity calculation formula of CFST based on the unified theory was modified and accounts for ambient temperature. [ABSTRACT FROM AUTHOR]

To analyze the heat transfer characteristics of oil shale under different in situ pyrolysis methods from a microscopic perspective, a combination of experimental and simulation approaches was employed. Initially, high-temperature in situ pyrolysis experiments on single-fracture oil shale were conducted using high-temperature steam and electrical methods. Subsequently, micro-CT scanning technology was utilized to obtain digital rock cores under different in situ pyrolysis conditions. Finally, these digital rock cores were seamlessly integrated with COMSOL 6.0 to achieve numerical simulations of high-temperature steam convective heating and electrical conductive heating in the in situ state. The relevant conclusions are as follows: Firstly, during the in situ pyrolysis of oil shale with high-temperature steam convective heating, the overall temperature increase is uniform and orderly. Heat is conducted gradually from the pores and fractures to the matrix. The uneven distribution of pores and fractures causes an uneven temperature field, but no localized overheating occurs, which can effectively enhance the pyrolysis efficiency. Secondly, the heat transfer direction in electrical conductive heating is primarily inward along the normal direction of the heat source end face. The closer the section is to the heat source end face, the higher the rate of temperature increase. Within 1 s, the temperature rise at 100 μm (near the heat source end face) is 2.27 times that at 500 μm (near the farthest cross-section from the heat source end face). The heat transfer effect of high-temperature steam convective heating consistently surpasses that of electrical conductive heating. The Tc value initially increases and then decreases as pyrolysis progresses, reaching a maximum of 1.61331 at 0.4 s, but Tc remains greater than 1 throughout. Finally, in the initial stages of pyrolysis, the high-temperature region formed by conductive heating is superior to that of convective heating. However, once the heat carrier fluid flow stabilizes, the volume of the high-temperature region formed by convective heating grows rapidly compared to that of conductive heating. At 1 s, the volume of the high-temperature region formed by convective heating reaches 5.22 times that of the high-temperature region formed by conductive heating. [ABSTRACT FROM AUTHOR]

'Duli' (Pyrus betulifolia Bunge) is one of the main rootstocks of pear trees in China. Gibberellin (GA) is a key plant hormone and the roles of GA in nitrate (NO3−) uptake and metabolism in plants remain unclear. In this study, we investigated the effects of exogenous GA3 on the N metabolism of 'Duli' seedlings under NO3− deficiency. The results showed that exogenous GA3 significantly improves 'Duli' growth under NO3− deficiency. On the one hand, GA3 altered the root architecture, increased the content of endogenous hormones (GA3, IAA, and ZR), and enhanced photosynthesis; on the other hand, it enhanced the activities of N−metabolizing enzymes and the accumulation of N, and increased the expression levels of N absorption (PbNRT2) and the metabolism genes (PbNR, PbGILE, PbGS, and PbGOGAT). However, GA3 did not delay the degradation of chlorophyll. Paclobutrazol had the opposite effect on growth. Overall, GA3 can increase NO3− uptake and metabolism and relieve the growth inhibition of 'Duli' seedlings under NO3− deficiency. [ABSTRACT FROM AUTHOR]