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The non-adiabatic relaxation processes and the fragmentation dynamics of Rydberg-excited N,N,N′,N′-tetramethylmethylenediamine (TMMDA) are investigated using femtosecond time-resolved photoelectron imaging and time-resolved mass spectroscopy. Excitation at 208 nm populates TMMDA in a charge-localized 3p state. Rapid internal conversion (IC) to 3s produces two charge-delocalized conformers with independent time constants and distinct population ratios. As the system explores the 3s potential surface, the structural evolution continues on a 1.55 ps timescale, followed by a slower (12.1 ps) relaxation to the ground state. A thorough comparison of the time-dependent mass and photoelectron spectra suggests that ionization out of the 3p state ends up with the parent ion, the vibrational energy of which is insufficient for the bond cleavage. On the contrary, by virtue of the additional energy acquired by IC from 3p, the internal energy deposited in 3s is available to break the C–N bond, leading to the fragment ion. The fragmentation is found to occur on the ion surface instead of the Rydberg surface. [ABSTRACT FROM AUTHOR]

To investigate the progress of disparities in human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), gonorrhea, and syphilis among children and adolescents aged 6–22 years in China during 2013–2021. A total of 614 325 cases data were extracted from the Chinese Information System for Infectious Diseases Control and Prevention during 2013–2021. Puberty health education data were drew from the Student Health Surveillance in 2021. Disparity patterns and average annual percentage changes (AAPCs) in sexually transmitted infections (STIs) incidence or new cases in China were examined using descriptive statistics and joinpoint regression. The incidence across 345 cities was stratified by gross domestic product (GDP). Between 2013 and 2021, there were 614 325 reported cases of HIV/AIDS, gonorrhea, and syphilis among children and adolescents aged 6–22, with an annual average incidence of 24.0967 per 100 000. The expansion of HIV/AIDS has halted, yet the surge in gonorrhea and syphilis remains notably pronounced. The ratio of male to female AIDS incidence increased from 2.75 (2.60, 2.90) to 7.13 (6.68, 7.62), but that of syphilis changed from 0.33 (0.32, 0.34) to 0.56 (0.55, 0.57). Students and out‐of‐school individuals aged 13–15 experienced a notably high increase in STI cases, surpassing other age groups, with an average annual percentage increase of 29.2% and 26.3%, respectively. Nonstudents consistently had a higher incidence rate than students, with an IRR reaching 31.80 (31.24, 32.37) in 2021. A noticeable clustering pattern of new cases emerged in the southeastern region of the Heihe‐Tengchong line, extending inland from the coastal areas. Districts and counties with lower rates of puberty sexual health education tended to have higher average STI incidence rates. At the prefecture and city levels, there was a noticeable upward trend on average STI incidence rates in cities with per capita GDPs. Strategies to address those disparities include promoting equitable health education, and widespread sexual health education, particularly in areas with limited access to education and experiencing rapid economic development. The effectiveness of sexual health education intervention needs to be further evaluated in well‐designed studies. [ABSTRACT FROM AUTHOR]

Increased nitrogen (N) application has profound effects on CO2 flux in croplands. The aim of this study is to investigate the effects of long-term N addition on soil respiration (SR) in a rainfed winter wheat (Triticum aestivum L.) field in the Loess Plateau of China. Two wheat cultivars were planted under three levels of N application (0, 180, and 360 kg N ha−1 year−1) in non-irrigated cropland from 2004 to 2013. The diurnal and seasonal SR variations and abiotic and biotic factors were measured during the growing seasons in 2012–2013. The results showed that N180 and N360 increased the cumulative CO2 flux by 30.3% and 32.4% on average after 5 and 10 years of N application, respectively. Multiple regressions revealed that the seasonal SR was mainly controlled by the soil temperature (ST), at a depth of 8 cm, and the leaf area index. Diurnal SR was mainly controlled by the ST and the net photosynthesis rate. Long-term N application stimulated SR by increasing the photosynthetic leaf area and temperature sensitivity. Overall, N application at a rate of 360 kg N ha−1 year−1 did not reach the threshold for limiting SR in the investigated semi-humid rainfed wheat cropland in the Loess Plateau of China. [ABSTRACT FROM AUTHOR]

Selenium (Se) is a micronutrient known for its essential role in human health and plant metabolism. Waxy maize (Zea mays L. sinensis kulesh)—known for its high nutritional quality and distinctive flavor—holds significant consumer appeal. Therefore, this study aims to assess the effects of foliar Se spraying on the nutritional quality of waxy maize grains, with a focus on identifying varietal differences and determining optimal Se dosage levels for maximizing nutritional benefits. We employed a two-factor split-plot design to assess the nutritional quality, trace elements, and pigment content of jinnuo20 (J20) and caitiannuo1965 (C1965) at the milk stage after being subjected to varying Se doses sprayed on five leaves. Our findings indicate superior nutrient content in J20 compared to C1965, with both varieties exhibiting optimal quality under Se3 treatment, falling within the safe range of Se-enriched agricultural products. JS3 (0.793) demonstrated the highest overall quality, followed by JS2 (0.606), JS4 (0.411), and JS1 (0.265), while CS0 had the lowest (−0.894). These results underscore the potential of foliar biofortification to enhance the functional component contents of waxy maize grains. [ABSTRACT FROM AUTHOR]

Coherent nuclear wavepacket behavior obtained by time-resolved spectroscopy is a good choice to capture the real-time evolution of molecular configuration. Using femtosecond time-resolved photoelectron imaging, we investigate the real-time evolution of the vibrational wavepacket of 2,5-difluoroaniline following the coherent excitation of an out-of-plane vibrational mode in the S1 state at 289.8 nm. Probed by an accidental resonance with the Rydberg states, the periodic oscillations with the frequency of 99 cm−1 are observed from the photoelectron kinetic energy (PKE) distributions, corresponding to the energy difference between the out-of-plane mode X10 of C–F bond and the band origin. Moreover, phase reversal of π rad between 0.66–0.75 and 1.00–1.08 eV is also observed in the PKE region. Combined with the scan of the potential energy surface in the ground cationic D0 state, the observed two ionization channels corresponding to different phases are attributed to the periodic geometry changes between the planar and the non-planar structures when the coherent wavepacket evolves from the initial vertical Franck–Condon region toward the global minimum of the S1 potential energy surface. [ABSTRACT FROM AUTHOR]

The photochemical isomerization and nonradiative decay processes of hexafluorobenzene (HFB) were investigated theoretically to gain insights into its photochemical mechanism and the perfluoro effect. A complete mechanistic scheme is presented through the characterization of all the possible minima and transition states of the S0, S1, and S2 states at the CASPT2/6-311G**//CAS(6,7)/6-31G* level. On the S0 potential energy surface, HFB could isomerize to three different products [Dewar-HFB (S0-P1), benzvalene-HFB (S0-P2), and fulvene-HFB (S0-P3)]. Following excitation to the S2 state with the perpendicular π → σ* transition, a chair-type minimum with Cs symmetry was found on the S2 potential energy surface. The adjacent S2/S1 conical intersection was immediately accessible from the S2 minimum. The nature of the S1 state was confirmed to have a π → π* character. Both the S2 and S1 photochemistries of HFB yielded Dewar-HFB via the S1/S0 conical intersection. The regeneration of the S0 state from the S1 and T2 states via intersystem crossing or internal conversion was also revealed. [ABSTRACT FROM AUTHOR]

To exhaustively explore the association of infant genetic polymorphisms of methionine synthase (MTR) gene with the risk of non-syndromic congenital heart disease (CHD). A hospital-based case–control study involving 620 CHD cases and 620 health controls was conducted from November 2017 to March 2020. Eighteen SNPs were detected and analyzed. Our date suggested that the genetic polymorphisms of MTR gene at rs1805087 (GG vs. AA: aOR = 6.85, 95% CI 2.94–15.96; the dominant model: aOR = 1.77, 95% CI 1.35–2.32; the recessive model: aOR = 6.26, 95% CI 2.69–14.54; the addictive model: aOR = 1.81, 95% CI 1.44–2.29) and rs2275565 (GT vs. GG: aOR = 1.52, 95% CI 1.15–1.20; TT vs. GG: aOR = 4.93, 95% CI 1.93–12.58; the dominant model: aOR = 1.66, 95% CI 1.27–2.17; the recessive model: aOR = 4.41, 95% CI 1.73–11.22; the addictive model: aOR = 1.68, 95% CI 1.32–2.13) were significantly associated with the higher risk of CHD. And three haplotypes of G-A-T (involving rs4659724, rs95516 and rs4077829; OR = 5.48, 95% CI 2.58–11.66), G-C-A-T-T-G (involving rs2275565, rs1266164, rs2229276, rs4659743, rs3820571 and rs1050993; OR = 0.78, 95% CI 0.63–0.97) and T-C-A-T-T-G (involving rs2275565, rs1266164, rs2229276, rs4659743, rs3820571 and rs1050993; OR = 1.60, 95% CI 1.26–2.04) were observed to be significantly associated with risk of CHD. Our study found that genetic polymorphisms of MTR gene at rs1805087 and rs2275565 were significantly associated with higher risk of CHD. Additionally, our study revealed a significant association of three haplotypes with risk of CHD. However, the limitations in this study should be carefully taken into account. In the future, more specific studies in different ethnic populations are required to refine and confirm our findings. Trial registration: Registration number: ChiCTR1800016635; Date of first registration: 14/06/2018. [ABSTRACT FROM AUTHOR]

Evidence suggests that periconceptional folic acid supplementation may prevent congenital heart disease (CHD). Methionine synthase reductase (MTRR) is one of the key regulatory enzymes in the folate metabolic pathway. This study aimed to comprehensively evaluate the association of single nucleotide polymorphisms (SNPs) in the maternal MTRR gene with CHD risk in offspring. A hospital-based case-control study involving 740 mothers of CHD cases and 683 health controls was conducted. The study showed that maternal MTRR gene polymorphisms at rs1532268 (C/T vs. C/C: aOR = 1.524; T/T vs. C/C: aOR = 3.178), rs1802059 (G/A vs. G/G: aOR = 1.410; A/A vs. G/G: aOR = 3.953), rs2287779 (G/A vs. G/G: aOR = 0.540), rs16879334 (C/G vs. C/C: aOR = 0.454), and rs2303080 (T/A vs. T/T: aOR = 0.546) were associated with the risk of CHD. And seven haplotypes were observed to be associated with the risk of CHD, T-G-A haplotype (OR = 1.298), C-A-C-C (OR = 4.824) and A-G haplotype (OR = 1.751) were associated with increased risk of CHD in offspring; A-A-A (OR = 0.773), T-A-A (OR = 0.557), G-A-C-C (OR = 0.598) and G-C (OR = 0.740) were associated with decreased risk of CHD in offspring. Maternal MTRR gene polymorphisms were associated with CHD in offspring, and its haplotypes have affected the occurrence of CHD. Furthermore, given the complexity and heterogeneity of CHD, the mechanisms by which these factors influence offspring cardiac development remain unknown, and studies in larger samples in an ethnically diverse population are needed. [ABSTRACT FROM AUTHOR]

The simulation technology of the nuclear power plant are gradually applying to the nuclear power industry. However, most of the research on nuclear power plant simulation system only focus on pure computerized simulation at present, and it is difficult to fully display the characteristics of the simulating objects. In order to simulate the response characteristics of control system more really, a hardware-in-loop simulation platform of main control systems in the nuclear power plant has been developed in this paper. This simulation platform consists of thermal-hydraulic model, control and protection system model, physical DCS system and real-time interactive database. A physical industrial DCS system has been coupled to this platform to simulate the main control systems in the NPP, which makes the simulation result much closer to the actual control systems. The devoloped simulation platform has been validated by some steady and transient cases in this paper. This hardware-in-loop simulation platform can be used in the simulation and optimal design of NPP control systems. Furthermore, it can be used in the failure mode and effect analysis of the instrumentation and control systems in the nuclear power plant.

The purpose of this study is to investigate whether the link between pre-pregnancy overweight/obesity and risk of macrosomia is mediated by both gestational diabetes mellitus (GDM) and high maternal triglyceride (mTG) levels. This prospective study finally included 29,415 singleton term pregnancies. The outcome of interest was macrosomia (≥4000 g). High mTG levels were denoted as values ≥90th percentile. GDM was diagnosed using a standard 75 g 2 h oral glucose tolerance test. The mediation analysis was conducted using log-binomial regression while controlling for maternal age, education, parity, gestational weight gain, gestational hypertension, smoking, drinking and infant sex. Overall, 15.9% of pregnant women were diagnosed with GDM, and 4.3% were macrosomia. Mediation analysis suggested that overweight had a total effect of 0.009 (95% CI, 0.006–0.013) on macrosomia, with a direct effect of 0.008 (95% CI, 0.004–0.012) and an indirect effect of 0.001 (95% CI, 0.001–0.002), with an estimated proportion of 11.1% mediated by GDM and high mTG levels together. Furthermore, we also discovered a total effect of obesity on macrosomia of 0.038 (95% CI, 0.030–0.047), consisting of a direct effect of 0.037 (95% CI, 0.028–0.045) and an indirect effect of 0.002 (95% CI, 0.001–0.002), with an estimated proportion of 5.3% mediated by GDM and high mTG levels combined. Both GDM and high mTG levels enhanced the risk of macrosomia independently and served as significant mediators in the relationship between pre-pregnancy overweight/obesity and macrosomia. [ABSTRACT FROM AUTHOR]

This study attempted to learn the association between maternal betaine-homocysteine methyltransferase (BHMT) gene polymorphisms, maternal dietary habits, and their interactions with the risk of ventricular septal defects (VSD) in offspring. A total of 426 mothers of VSD children and 740 control mothers were included in the study. Logistic regression was used to evaluate the level of associations and interaction effects. Our study suggested that mothers reporting excessive intake of smoked foods (aOR = 2.44, 95%CI: 1.89–3.13), barbecued foods (aOR = 1.86, 95%CI: 1.39–2.48), fried foods (aOR = 1.93, 95%CI: 1.51–2.46), and pickled vegetables (aOR = 2.50, 95%CI: 1.92–3.25) were at a significantly higher risk of VSD in offspring, instead, mothers reporting regular intake of fresh fruits (aOR = 0.47, 95%CI: 0.36–0.62), fish and shrimp (aOR = 0.35, 95%CI: 0.28–0.44), fresh eggs, (aOR = 0.56, 95%CI: 0.45–0.71), beans (aOR = 0.68, 95%CI: 0.56–0.83), and milk products (aOR = 0.67, 95%CI: 0.56–0.80) were at a lower risk of VSD in offspring. In addition, maternal BHMT gene polymorphisms at rs1316753 (CG vs. CC: aOR = 2.01, 95%CI: 1.43–2.83) and rs1915706 (CT vs. TT: (aOR = 1.81, 95%CI: 1.33–2.46) were significantly associated with increased risk of VSD in offspring. Furthermore, a significant interaction between BHMT polymorphisms and maternal bean intake was identified in the study. In conclusion, Maternal BHMT polymorphisms at rs1316753 and rs1915706, dietary habits as well as their interaction were observed to be significantly associated with the risk of VSD in offspring. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of Huangqi Liuyi decoction extract (HQD) on diabetic nephropathy (DN), and the tissue distribution difference of six main active ingredients of HQD between normal and DN mouse models. DN mice were administered HQD for 12 weeks to investigate its efficacy in the treatment of DN. Liquid chromatography-tandem mass-spectrometry (HPLC-MS/MS) was used to analyze the tissue distribution of the six active ingredients of HQD in normal and DN mice, including astragaloside IV, calycosin-7-O-β-D-glucoside, calycosin glucuronide, ononin, formononetin, and glycyrrhizic acid. DN mice treated with HQD showed significantly decreased fasting blood glucose (FBG), 24-h urinary protein (24 h U-Alb), blood urea nitrogen (BUN), serum creatinine (Scr), and triglyceride levels (TG) (p < 0.05). Moreover, there were no significant differences in pharmacodynamics between HQD and Huangqi Liuyi decoction. Treated mice also had decreased expression of collagen I, ɑ–smooth muscle actin (ɑ-SMA), and vimentin; and upregulated expression of E-cadherin in their kidneys. Compared to normal mice, distributions of the six ingredients in the liver, heart, spleen, lungs, kidneys, stomach, small intestine, brain, and muscle of DN mice were different. The results indicated that the HQD could be used for the treatment of DN and to improve renal function. The pathological state of diabetic nephropathy may affect tissue distribution of HQD active ingredients in mice. [ABSTRACT FROM AUTHOR]

Huangqi Liuyi decoction is a famous traditional Chinese medicine (TCM) that has been widely used in China for the management of diabetes since the Song Dynasty. Today, it is commonly used for treating diabetic nephropathy (DN). Our previous experimental studies have suggested that the mixture HQD, containing astragalus saponin, astragalus flavone, astragalus polysaccharide, and glycyrrhetinic acid, could be used for the treatment of DN and to improve renal function. The objective of this study was to develop a sensitive and reliable high-performance liquid chromatography-tandem mass spectrometry method for simultaneous quantitation of astragaloside IV, calycosin-7-O-β-D-glucoside, calycosin-glucuronide, ononin, formononetin, and glycyrrhizic acid, which are the main active constituents in HQD, and to compare the pharmacokinetics of these active constituents in control and DN mice orally treated with HQD. The results indicated that the pharmacokinetic parameters of HQD were significantly different between the control and DN mouse groups. The absorption of HQD in the DN mice was greater than that in control mice. [ABSTRACT FROM AUTHOR]

This study aimed at examining the risk of macrosomia, in relation to maternal pre-pregnancy overweight/obesity mediated via high maternal triglyceride (mTG) levels. In this prospective study, 24,730 singleton term non-diabetic pregnancies were finally included. Serum mTG levels were measured using fasting blood samples that were collected after 28 weeks of gestation. High mTG levels were defined as values ≥ the 90th percentile. The outcome of interest was macrosomia (≥4000 g). Log-binomial regression was used to assess the mediation path between overweight/obesity, high mTG levels, and macrosomia. The mediation analysis found a total effect of overweight on macrosomia of 0.006 (95% CI, 0.001–0.010), including a direct effect of 0.005 (95% CI, 0.001, 0.009) and indirect effect of 0.001 (95% CI, 0.000–0.001), with an estimated proportion of 11.1% mediated by high mTG levels. Additionally, we also found a total effect of obesity on macrosomia of 0.026 (95% CI, 0.018–0.036), including a direct effect of 0.025 (95% CI, 0.017–0.036) and indirect effect of 0.001 (95% CI, 0.000–0.001), with an estimated proportion of 3.8% mediated by high mTG levels. In conclusion, non-diabetic women with overweight or obesity had an increased risk of macrosomia, and this positive association was partly mediated by high mTG levels. [ABSTRACT FROM AUTHOR]