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To evaluate the prevalence of vitamin D deficiency in pregnant women and their newborns in Beijing, China and the influence of vitamin D deficiency on birth size. A cross-sectional study. Data were collected from pregnant women who delivered during April to May 2010 at 306 Hospital of PLA in Beijing, China. Participants in the study were seventy healthy nulliparous pregnant women with singleton pregnancies who delivered healthy babies at full term and their newborns. Severe vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25 nmol/l) was detected in 54·5 % of mothers and 46·6 % of newborns. Neither mothers nor newborns had serum 25(OH)D concentrations that reached the normal level (>75 nmol/l). The concentration of 25(OH)D in mothers was positively correlated with that in cord blood (r = 0·89, P < 0·001). Newborns of mothers with severe vitamin D deficiency had lower birth length and birth weight. The head circumference and birth weight were lower in vitamin D-deficient newborns. The study indicates that pregnant women and neonates residing in Beijing are at high risk of vitamin D deficiency. Neonatal 25(OH)D concentrations are dependently related to maternal 25(OH)D levels. Maternal and neonatal vitamin D status influences newborn size.

The failure of wind turbine blade bolts is a critical issue threatening the safe operation of wind turbines. This study investigates the bolt fracture cases of the #7 and #8 wind turbines in a wind farm. Through on-site inspections, fracture analysis, and numerical simulations, the fracture mechanism is revealed, and systematic prevention and control strategies are proposed. Failure mechanism analysis indicates that the primary cause of bolt fracture is insufficient preloading, leading to a decrease in fatigue strength. Crack initiation occurred in the stress concentration area of the threads (the 3rd to 5th threads), and the fracture surface displayed typical fatigue striations and brittle fracture features. Indirect causes include inadequate design specification compatibility (the M30 bolt diameter is significantly smaller than the M36 standard used in similar models, with a tensile strength reduction of approximately 30%) and installation process defects (such as uneven application of lubricants and hydraulic tensioning tool errors). The optimization strategies proposed include: ① adopting ultrasonic preloading direct measurement technology (accuracy ±3%) combined with electromagnetic ultrasonic axial force detection for early bolt damage identification; ② upgrading the bolt specification to M36 and optimizing the thread transition fillet (R≥1mm). Finite element analysis shows that the allowable stress increases from 854.5 MPa to 940 MPa after the improvement; ③ standardizing the installation process by implementing the torque-angle dual control method and full-thread lubrication to reduce preloading variability (tightening coefficient reduced from 1.4 to 1.3); ④ establishing a bolt health archive and an online monitoring system, with real-time early warning using a multi-channel ultrasonic device. After implementing these measures in a project, the fault response efficiency improved by 70%.The study validates that these measures can reduce the fracture risk by 50% and provide empirical cases for preventive maintenance of wind turbines. In the future, integrating digital twins and machine learning technologies will enable bolt life prediction and proactive maintenance, advancing the intelligent transformation of wind turbine operations and maintenance.

Excessive vibration was observed in the main steam drainage pipeline on the turbine side of a power plant. Through inspections of the pipeline support system and vibration monitoring at selected measurement points, this paper investigates the root causes and proposes mitigation measures. The analysis reveals that the vibration amplitude of the drainage pipeline in Unit #1 is significantly higher than that in Unit #2, primarily attributed to the longer spring hanger rods, insufficient positional restraints, and excessive pipeline length, which collectively reduce the structural stiffness and increase flexibility of the drainage system. To suppress vibrations, a combined approach is recommended: enhancing system stiffness (e.g., optimizing hanger configurations) and installing viscoelastic dampers to dissipate vibration energy.

This paper analyzes the economic and environmental impact on China of carbon tariffs from the perspective of the taxed countries based on a static global multiregional economy-energy-environment (3E) CGE model. The results show that carbon tariffs will severely depress China's exports to the Annex I countries, and then have negative impacts on China's macro-economy. In terms of environmental effects, carbon tariffs indeed will reduce carbon emissions of China slightly, while such emission reduction effects will be offset by the increased emissions of Annex I countries led to by carbon tariffs. Carbon tariffs have a serious negative economic impact and very weakly positive environmental impact on the countries imposed carbon tariffs, which should be an important consideration for the reasonability and feasibility of carbon tariffs.

The mixed halide perovskites have emerged as outstanding light absorbers for efficient solar cells. Unfortunately, it reveals inhomogeneity in these polycrystalline films due to composition separation, which leads to local lattice mismatches and emergent residual strains consequently. Thus far, the understanding of these residual strains and their effects on photovoltaic device performance is absent. Herein we study the evolution of residual strain over the films by depth-dependent grazing incident X-ray diffraction measurements. We identify the gradient distribution of in-plane strain component perpendicular to the substrate. Moreover, we reveal its impacts on the carrier dynamics over corresponding solar cells, which is stemmed from the strain induced energy bands bending of the perovskite absorber as indicated by first-principles calculations. Eventually, we modulate the status of residual strains in a controllable manner, which leads to enhanced PCEs up to 20.7% (certified) in devices via rational strain engineering. The residual strains in the mixed halide perovskite thin films and their effects on the solar cell devices are less understood. Here Zhu et al. study the impact of the gradient in-plane strain on the carrier dynamics of the strained perovskite films and optimize the device efficiency.

With the proposed goals of reaching its “carbon peak” by 2030 and becoming “carbon neutral” by 2060, China will comprehensively build a diversified, efficient and clean energy system. The differences in China’s resource endowments have made the development of carbon emission reduction in the thermal power industry uncoordinated in various regions. Therefore, it is necessary to optimize the method for measuring thermal power carbon emission efficiency and determine the impact of regional development imbalances on the carbon emission efficiency of thermal power. For this article, we used the stochastic frontier analysis method and selected a variety of influencing factors as technical inefficiency items. After that, we measured the thermal power carbon emission efficiency in 30 provinces and municipalities (autonomous regions) in China in the past 10 years, and it was found that the efficiency was increasing yearly and showed obvious spatial differences. The impact of the clean energy substitution effect on the thermal power carbon emission efficiency cannot be ignored. After performing a coupled and coordinated analysis on the efficiency of thermal carbon emission in various regions and its influencing factors, the three indicators of power consumption intensity, urbanization level and clean energy substitution effect were selected. The weight of the indicator subsystem was determined in view of the estimation of the technical inefficiency. The results of the coupling and coordination analysis show that the degree of coupling and coordination of thermal power carbon emission efficiency is increasing yearly and presents a distribution of “high in the eastern region and low in the western region”. Therefore, all provinces need to vigorously carry out clean replacement work to enhance the coordinated development of carbon emission reduction in the thermal power industry and the level of regional economic development.

• Light induces anthocyanin accumulation and hence decides the coloration of apple fruit. It also plays a key role in regulating the biosynthesis of other secondary metabolites. However, the crosstalk between anthocyanin and lignin metabolism during light induction, which affects the edible quality and visual quality of apple fruit, respectively, have rarely been characterized. • In this study, we identified and functionally elucidated the roles of miR7125 and its target, cinnamoyl-coenzyme A reductase gene (CCR), in regulating the homeostasis between anthocyanin and lignin biosynthesis during light induction. Overexpressing miR7125 or inhibiting CCR transiently in apple fruit promoted anthocyanin biosynthesis but reduced lignin production under light-induced conditions. Consistently, opposite results were observed under the background of repressed miR7125 or overexpressed CCR. • We found that the repressor MdMYB16 and the activator MdMYB1 bound to the miR7125 promoter. Transient repression of MdMYB16 upregulated miR7125 expression significantly, accompanied by decreased levels of MdCCR transcript, resulting in a reduction in the lignin biosynthesis and an increase in anthocyanin accumulation. However, transient overexpression of MdMYB16 produced the opposite effects to MdMYB16-RNAi. • The results reveal a novel mechanism by which the MdMYB16/MdMYB1-miR7125-MdCCR module collaboratively regulates homeostasis between anthocyanin and lignin biosynthesis under light induction in apple.

Under the “carbon peaking and carbon neutrality” goal, Shanxi Province adjusts the power supply structure and promotes the development of a high proportion of new energy, which has a certain impact on the demand for thermal coal. Therefore, constructing a reasonable forecasting model for thermal coal demand can play a role in stabilizing coal supply and demand. This paper analyzes various factors related to coal demand, and uses Pearson coefficient to screen out six variables with strong correlation. Then, based on the scenario analysis method, combined with the “14th Five-Year Plan” of Shanxi Province, different scenarios of economic development and carbon emission reduction development are set. Finally, a multi-scenario GA–LSSVM forecasting model of thermal coal demand in Shanxi Province is constructed, and the future development trend of thermal coal demand in Shanxi Province is predicted. The results show that the demand for thermal coal is the largest in the mode of high-speed economic development and low emission reduction, and the demand for thermal coal is the lowest in the mode of low-speed economic development and strong emission reduction, which provides a scientific basis for the implementation of Shanxi Province’s thermal coal supply policy.

Zengcheng (ZC), a superior cultivar of Mesona chinensis Benth, is distinguished by its unique sensory attributes and exceptional phytochemical quality, rendering it the cultivar of choice for commercial production. In this investigation, we employed comprehensive targeted metabolomics to systematically delineate the volatile metabolome of ZC in comparison to three relevant counterparts grown under uniform field conditions and harvested at the same developmental stage. Our primary objectives were to (i) quantitatively characterize the metabolomic divergence between ZC and the comparative cultivars, and (ii) elucidate the molecular basis underlying ZC’s characteristic flavor signature. Through high-throughput gas chromatography–mass spectrometry (GC-MS) analysis, a total of 1767 volatile metabolites were confidently annotated, with terpenoids and esters identified as the predominant chemical classes. Notably, ZC exhibited significantly elevated levels of terpenoids, esters, and aldehydes, which collectively conferred an intensified green, sweet, herbal, and fruity aroma. Key discriminatory metabolites included geranyl formate and geranic acid (imparting a pronounced green note), which were identified as pivotal determinants of ZC’s unique flavor profile. These findings provide mechanistic insights into the biochemical pathways governing flavor development in M. chinensis Benth and establish a robust foundation for precision-breeding strategies aimed at enhancing sensory quality and developing elite cultivars.