The association of female reproductive factors with risk of metabolic syndrome in women from NHANES 1999-2018.

BACKGROUND: Female reproductive factors such as age at first birth (AFB), age at last birth (ALB), number of pregnancies and live births play an essential role in women's health. However, few epidemiological studies have evaluated the association between female reproductive factors and metabolic syndrome (MetS). We therefore conducted a cross-sectional study to investigate the association between MetS risk and female reproductive factors. METHODS: We investigated the relationship between AFB, ALB, number of pregnancies and live births and the incidence of MetS using publicly available data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Weighted multivariable logistic regression analysis, restricted cubic spline (RCS) model, and subgroup analysis were used to evaluate the association between AFB and ALB and the risk of MetS in women. In addition, the relationship between the number of pregnancies, live births and MetS risk was also explored. RESULTS: A total of 15,404 women were included in the study, and 5,983 (38.8%) had MetS. RCS models showed an N-shaped relationship between AFB and MetS risk, whereas ALB, number of pregnancies, and live births were linearly associated with MetS. Weighted multivariable logistic regression analysis showed that the number of live births was associated with MetS risk, with ORs of 1.18 (95% CI: 1.04, 1.35) for women with ≥ 5 deliveries compared to women with ≤ 2 births. CONCLUSIONS: AFB was associated with the risk of MetS in an N-shaped curve in women. In addition, women with high live births have a higher incidence of MetS.

Exploring the Aromaticity Differences of Isoelectronic Species of Cyclo[18]carbon (C18), B6C6N6, and B9N9: The Role of Carbon Atoms as Connecting Bridges.

The cyclo[18]carbon (C18) has piqued widespread interest in recent years for its geometrical aesthetic and unique electronic structure. Inspired by it, theoretical investigations of its isoelectronic B9N9 have been published occasionally; however, few studies considered their other companion B6C6N6. In this work, we study the geometric structure, charge distribution, bonding characteristic, aromaticity, and electron delocalization of B6C6N6 and B9N9 for the first time and compare the relevant results with those of C18. Based on the comprehensive analysis of aromaticity indicators such as AV1245, nucleus-independent chemical shifts, anisotropy of the induced current density, magnetically induced current density, iso-chemical shielding surface, and induced magnetic field (Bind), we found that B6C6N6 has definitely a double aromatic character similar to C18 and the aromaticities of the two are very close, while B9N9 is a nonaromatic species. In response to this novel finding, we delved into its nature from an electron delocalization perspective through a localized orbital locator, electron localization function, Fermi hole, and atomic remote delocalization index analyses. The C atom between B and N as an interconnecting bridge strengthens the electron delocalization of the conjugate path, which is the essence of the significant enhancement of the molecular aromaticity from B9N9 to B6C6N6. This work elucidates that within the framework of the isoelectronicity of C18, different methods of atomic doping can achieve molecules with completely different properties.

Precarious Employment and Subjective Career Success During the School-to-Work Transition.

Purpose: The transition from school to work is an important stage in the career development of university students, and precarious employment during this period can significantly impact their early career success. In today's unstable employment environment, this study examines how employment instability during the transition from school to work directly and indirectly affects college students' subjective career success. This contributes to a thorough understanding of this transitional period and provides university students with the necessary resources to cope with a smooth transition from school to work. Patients and Methods: We recruited senior students at five universities in Harbin, China, from May to July 2022. After obtaining participants' consent, questionnaires were distributed via social media, resulting in 967 valid questionnaires. Based on this sample, we examined the chain mediating effect of financial stress and occupational self-efficacy in the association between precarious employment and career success and the moderating effect of employability. Results: The study found that precarious employment hurts career success and can also affect career success by increasing financial stress and decreasing occupational self-efficacy among college students. At the same time, financial stress can also decrease students' self-efficacy. Finally, employability can reduce the adverse effects of precarious employment on career success and occupational self-efficacy. Conclusion: The link between employment instability and subjective career success during the transition from school to work has been demonstrated for university students. Employment instability not only increases college students' financial stress but also reduces career self-efficacy, which in turn affects college students' perceptions of early subjective career success. Importantly, employability plays a positive role in the smooth school-to-work transition and subjective career success of university students.

Genetic Variation of Magnaporthe oryzae Population in Hunan Province.

Studies on the population structure and variation of Magnaporthe oryzae in fields are of great significance for the control of rice blast disease. In this study, a total of 462 isolates isolated from different areas of Hunan Province in 2016 and 2018 were analyzed for their population structure and variation tendency. The results showed that from 2016 to 2018, the concentration of fungal races of M. oryzae increased and the diversity decreased; furthermore, 218 isolates in 2016 belonged to ZA, ZB, ZC, ZE, ZF and ZG, with a total of 6 groups and 29 races, in which the dominant-population ZB group accounted for 66.2%; meanwhile, in 2018, 244 isolates were classified into 4 groups and 21 races, including ZA, ZB, ZC and ZG, in which the dominant-population ZB group accounted for 72.54%. In 2018, isolates of ZD, ZE and ZF populations were absent, and the number of total races and isolates of the ZA and ZC groups decreased. Fungal pathogenicity was identified, with 24 monogenic lines (MLs) carrying 24 major R genes. The resistance frequency of R genes to fungal isolates in 2018 decreased significantly, in which except Pikm was 64.5%, the other monogenic lines were less than 50%. Rep-PCR analysis for isolates of Guidong in Hunan also showed that fungal diversity decreased gradually. The influence of R genes on fungal variation was analyzed. The pathogenicity of isolates purified from Xiangwanxian 11 planted with monogenic lines was significantly more enhanced than those without monogenic lines. All the results indicated that in recent years, the fungal abundance in Hunan has decreased while fungal pathogenicity has increased significantly. This study will greatly benefit rice-resistance breeding and the control of rice blast disease in Hunan Province.

Design, Synthesis, and Fungicidal Activity against Rice Sheath Blight of Novel N-Acyl-1,2,3,4-tetrahydroquinoline Derivatives.

To discover fungicides with novel targets, a series of N-acyl-1,2,3,4-tetrahydroquinoline (NATHQ) derivatives were designed and synthesized by linking the active substructure NATHQ moiety in aspernigerin with the O-benzyl oxime-ether scaffold in commercial agrochemicals. Target compound structures were identified using proton and carbon-13 nuclear magnetic resonance spectroscopies and high-resolution mass spectrometry. Preliminary bioassays indicated that at 40 mg/L, some target compounds exhibited moderate to considerable in vitro fungicidal activities against Rhizoctonia solani and Botrytis cinerea. In particular, compound 3j exhibited higher fungicidal activities both in vitro (EC50 = 0.733 mg/L) and in vivo (EC50 = 15.2 mg/L) against R. solani than the commercial fungicide prochloraz; therefore, it should be a promising fungicide candidate against rice sheath blight. Additionally, compound 3j exhibited good laccase inhibitory activity (73.2% at 200 mg/L). Molecular docking revealed that the bis-cyano-oxime-ether moiety of compound 3j exhibited an excellent binding mode with the laccase target protein and could be used as a lead compound for developing laccase inhibitors. The structural features of these NATHQ derivatives will provide inspiration for developing laccase inhibitors and discovering more effective fungicides to control agricultural diseases.

Theoretical design of a dual-motor nanorotator composed of all-carboatomic cyclo[18]carbon and a figure-of-eight carbon hoop.

A novel supramolecular complex (2C18@OPP) constructed from two kinds of unique nanorings, all-carboatomic cyclo[18]carbon (C18) and figure-of-eight carbon hoop (OPP), has been studied theoretically from the perspective of an extraordinary dual-motor nanorotator. The rotational barrier of C18 in OPP is extremely small at ambient temperature, implying the possibility of the host-guest complex as an ultrafast nanorotator. The rotational characteristics and thermodynamic stability of the nanorotator at different temperatures were then explored. The rotational behaviors of the two C18 rings in OPP are basically independent of each other. The supramolecule investigated in this work is the first example of a dual-motor nanorotator that promises to be an important building block for constructing complicated molecular machines.

Molecular assembly with a figure-of-eight nanohoop as a strategy for the collection and stabilization of cyclo[18]carbon.

The recently synthesized novel figure-of-eight nanohoop with two strained oligoparaphenylenes (OPPs) was theoretically designed to collect and stabilize new allotropic carbon cyclo[18]carbon (C18) through molecular assembly. The size adaptability and shape complementarity of C18 to OPP make it possible for them to combine into extraordinary ring-in-ring supramolecules. Thermodynamic analysis of 2C18@OPP showed that the host-guest complex should spontaneously form below 404 K. Molecular dynamics (MD) simulations demonstrated that the assembly of C18 and OPP into host-guest complexes of up to 1 : 2 can occur at ambient temperature. Various real-space function analyses revealed that the nature of the non-covalent interaction between C18 and OPP is the van der Waals (vdW) attraction characterized by π-π stacking. Photoexcitation makes the host-guest complexes less stable in their S1 state by causing the central linker to flatten.

Effect of Final Thermomechanical Treatment on the Mechanical Properties and Microstructure of T Phase Hardened Al-5.8Mg-4.5Zn-0.5Cu Alloy.

The effect of final thermomechanical treatment (FTMT) on the mechanical properties and microstructure of a T-Mg32(Al Zn)49 phase precipitation hardened Al-5.8Mg-4.5Zn-0.5Cu alloy was studied. The as-cold rolled aluminum alloy samples were subjected sequentially to solid solution treatment, pre-deformation, and two-stage aging treatment. Vickers hardness was measured during the aging process under various parameters. Tensile tests were conducted on the representative samples based on the hardness results. Microstructural characteristics were analyzed via transmission electron microscopy and high-resolution transmission electron microscopy. The conventional T6 process was also carried out for comparison. The hardness and tensile strength are increased evidently by the FTMT process for the Al-Mg-Zn-Cu alloy, while the ductility is adversely affected to a small extent. The precipitation at the T6 state consists of a coherent Guinier-Preston zone and T″ phase in the form of intragranular, fine, and spherical particles, while a semi-coherent T' phase appears after the FTMT process as a new constituent. The distribution of dislocation tangles and isolated dislocations is another feature of FTMT samples. Enhanced precipitation hardening and dislocation strengthening account for the improved mechanical performance of FTMT samples.

Two nucleotide sugar transporters are important for cell wall integrity and full virulence of Magnaporthe oryzae.

Cell wall polysaccharides play key roles in fungal development, virulence, and resistance to the plant immune system, and are synthesized from many nucleotide sugars in the endoplasmic reticulum (ER)-Golgi secretory system. Nucleotide sugar transporters (NSTs) are responsible for transporting cytosolic-derived nucleotide sugars to the ER lumen for processing, but their roles in plant-pathogenic fungi remain to be revealed. Here, we identified two important NSTs, NST1 and NST2, in the rice blast fungus Magnaporthe oryzae. Both NSTs were localized in the ER, which was consistent with a function in transporting nucleotide sugar for processing in the ER. Sugar transport property analysis suggested that NST1 is involved in transportation of mannose and glucose, while NST2 is only responsible for mannose transportation. Accordingly, deletion of NSTs resulted in a significant decrease in corresponding soluble saccharides abundance and defect in sugar utilization. Moreover, both NSTs played important roles in cell wall integrity, were involved in asexual development, and were required for full virulence. The NST mutants exhibited decreasing external glycoproteins and exposure of inner chitin, which resulted in activation of the host defence response. Altogether, our results revealed that two sugar transporters are required for fungal cell wall polysaccharides accumulation and full virulence of M. oryzae.

Design, Synthesis and Fungicidal Activity of N-(thiophen-2-yl) Nicotinamide Derivatives.

Based on the modification of natural products and the active substructure splicing method, a series of new N-(thiophen-2-yl) nicotinamide derivatives were designed and synthesized by splicing the nitrogen-containing heterocycle natural molecule nicotinic acid and the sulfur-containing heterocycle thiophene. The structures of the target compounds were identified through 1H NMR, 13C NMR and HRMS spectra. The in vivo bioassay results of all the compounds against cucumber downy mildew (CDM, Pseudoperonospora cubensis (Berk.et Curt.) Rostov.) in a greenhouse indicated that compounds 4a (EC50 = 4.69 mg/L) and 4f (EC50 = 1.96 mg/L) exhibited excellent fungicidal activities which were higher than both diflumetorim (EC50 = 21.44 mg/L) and flumorph (EC50 = 7.55 mg/L). The bioassay results of the field trial against CDM demonstrated that the 10% EC formulation of compound 4f displayed excellent efficacies (70% and 79% control efficacies, respectively, each at 100 mg/L and 200 mg/L) which were superior to those of the two commercial fungicides flumorph (56% control efficacy at 200 mg/L) and mancozeb (76% control efficacy at 1000 mg/L). N-(thiophen-2-yl) nicotinamide derivatives are significant lead compounds that can be used for further structural optimization, and compound 4f is also a promising fungicide candidate against CDM that can be used for further development.

Density-wave-ordered phases of Rydberg atoms on a honeycomb lattice.

Rydberg atom arrays have recently emerged to be a promising platform for the exploration of exotic quantum phases of matter and quantum phenomena. In this work, we map out the ground-state phase diagram of Rydberg atoms on a honeycomb lattice as a function of the Rydberg blockade radius and the laser detuning by performing large-scale finite-size density matrix renormalization group simulations. Apart from a featureless disordered phase, we find five other intricate long-range density-wave-ordered phases within a relatively wide parameter space. The properties of these quantum phases are analyzed by calculating their Rydberg excitation profiles and static structure factors. In addition, a continuous quantum phase transition belonging to the (2+1)-dimensional Ising universality class is explored by a standard finite-size scaling analysis. Our work implies some different physics, such as the possible nontrivial quantum phase transitions and a highly degenerate string ordered phase, that a honeycomb geometry could bring to the Rydberg system and serves as a numerical guide for possible real experiments.

FERONIA-like receptor 1-mediated calcium ion homeostasis is involved in the immune response.

Calcium (Ca2+) is the most abundant divalent cation in plants, and cellular levels of Ca2+, which functions as a nutrient and secondary messenger, play a critical role in plant immunity. In the present study, we found that FERONIA-like receptor 1 (FLR1) positively regulates Magnaporthe oryzae resistance and that expression of FLR1 is strongly induced in response to Ca2+ deficiency. In addition, the Ca content in the shoots of flr1 was lower than that in wild-type, and the M. oryzae-sensitive phenotype of the flr1 mutant was not rescued by exogenous application of Ca2+. Moreover, RNA sequencing revealed 2,697 differentially expressed genes (DEGs) in the flr1 mutant compared with wild-type, and some of these DEGs are involved in cellular metal ion homeostasis and transition metal ion homeostasis. Changes in expression of overlapping genes between the flr1 mutant and in plants under low-Ca2+ treatment were consistent in terms of direction, indicating that FLR1 is involved in Ca2+ homeostasis. In summary, we detected FLR1-mediated resistance to M. oryzae, a phenomenon associated with Ca2+ homeostasis.

Quantitative Evaluation of a Cross-Sectional Area of the Fetal Straight Sinus by Magnetic Resonance Imaging and Its Clinical Value.

Objective: The intracranial venous system plays an important role in ensuring blood circulation and a stable blood supply to the fetal brain. In the present study, a cross-sectional area of the fetal straight sinus was quantitatively evaluated by fetal magnetic resonance imaging (MRI) to explore the method's clinical value. Methods: The clinical and MRI data of 126 normal fetuses in mid-to-late stage pregnancies were retrospectively analyzed. The "dominant" sequence of the fetal straight sinus was selected, and the cross-sectional area of the lumen was measured at each gestational age to obtain the normal range at different ages and to analyze the developmental pattern and characteristics of the fetal straight sinus. Results: There were statistically significant differences in the cross-sectional area of the fetal straight sinus among different gestational ages (P < 0.05). The cross-sectional area of the fetal straight sinus was positively correlated with gestational age (coefficient of determination = 0.6892, P < 0.05). That is, the cross-sectional area of the fetal straight sinus grew with increasing gestational age, and the regression equation was y = 0.27 x - 2.14 (P < 0.05). Additionally, there were five fetuses with cerebral venous abnormalities, including four with heart failure and one with venous sinus thrombosis. Conclusion: Quantitative measurement of a cross-sectional area of the fetal straight sinus by MRI enhanced understanding of the anatomical features and developmental pattern of fetal cerebral veins and provided a reference for the clinical diagnosis of related diseases and investigation concerning pathogenesis.

Quantum phases of Rydberg atoms on a frustrated triangular-lattice array.

The neutral atoms coupled to a highly excited Rydberg state on a two-dimensional triangular lattice are investigated by employing the density matrix renormalization group technique in the matrix product state form. The full ground-state phase diagram as a function of blockade radius and the detuning of the exciting laser is determined by the behavior of entanglement entropy. We find several quantum phases including stripe-ordered and symmetry-breaking density-wave-ordered phases featured with regular excitation patterns of different excitation densities ρ = 1/3, 1/4, and 1/7. In addition, a ρ = 2/3 ordered phase and an interesting "order-by-disorder" phase, which has been prepared experimentally, are also observed in this work. Our work provides an exploration of the possible quantum phases that can occur in a triangularly arrayed Rydberg system, and thus could be a faithful theoretical guide for further experimental research.

Mimic Lipoproteins Responsive to Intratumoral pH and Allosteric Enzyme for Efficient Tumor Therapy.

Discoid-reconstituted high-density lipoprotein (d-rHDL) is advantageous for tumor-targeted drug delivery due to its small size, long circulation, and efficient internalization into cancer cells. Nevertheless, an allosteric reaction catalyzed by serum lecithin-cholesterol acyltransferase (LCAT) may cause drug leakage from d-rHDL and reduce its targeting efficiency. Conversely, similar "structural weakening" catalyzed by acyl-coenzyme A-cholesterol acyltransferase (ACAT) inside tumor cells can stimulate precise intracellular drug release. Therefore, we synthesized and characterized a pH-sensitive n-butyraldehyde bi-cholesterol (BCC) to substitute for cholesterol in the d-rHDL particle, and bovine serum albumin (BSA) was used as the targeting agent. This dual pH- and ACAT-sensitive d-rHDL (d-d-rHDL) was small with a disk-like appearance. Morphological transformation observation, in vitro release assays, and differences in internalization upon LCAT treatment confirmed that BCC effectively inhibited the remodeling behavior and enhanced the tumor-targeting efficiency. The accumulation of d-d-rHDL in HepG2 cells was significantly higher than that in LO2 cells, and accumulation was inhibited by free BSA. The pH sensitivity was verified, and d-d-rHDL achieved efficient drug release in vitro and inside tumor cells after exposure to acidic conditions and ACAT. Confocal laser scanning microscopy demonstrated that d-d-rHDL escaped from lysosomes and became distributed evenly throughout cells. Moreover, in vivo imaging assays in a tumor-bearing mouse model demonstrated tumor-targeting properties of d-d-rHDL, and paclitaxel-loaded d-d-rHDL showed strong anticancer activity in these mice. This dual-sensitive d-d-rHDL thus combines structural stability in plasma and an intracellular pH/ACAT-triggered drug release to facilitate inhibition of tumor growth.