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Thyroid dysfunction plays a role in blood pressure (BP) regulation. However, the associations between thyroid function and BP and arterial stiffness in the general Chinese population without thyroid disease are unknown. This population‐based cross‐sectional study aimed to investigate the association between thyroid function and peripheral and central BP and arterial stiffness in Chinese individuals. After excluding those who had thyroid diseases or incomplete clinical measurements, this study included 691 participants. Of the participants, 444 (64.2%) were women and 215 (31.1%) had hypertension. After adjustment for covariates, serum FT3 was significantly associated with a higher pulse rate in both sexes. In men, each 2.72‐fold increase in serum FT4 levels was associated with higher peripheral systolic BP (+10.82 mmHg, p = .005) and pulse pressure (+5.71 mmHg, p = .03). Each 2.72‐fold increase in serum FT4 levels was associated with higher central systolic BP (+8.03 mmHg, p = .03) and pulse pressure (+3.89 mmHg, p = .05). In women, serum FT4 was only associated with a higher central pulse pressure (+2.96 mmHg, p = .04). After adjustment for covariates, serum FT4 was significantly associated with a faster cfPWV exclusively in men. Our study showed that serum FT4 is associated with higher peripheral and central BP and faster cfPWV in men, whereas serum FT3 is positively associated with a higher pulse rate in both sexes, indicating that the effects of thyroid function on BP and arterial stiffness are more significant in men than in women.

Klotho, an important anti-aging protein, may be related to elevated blood pressure (BP) and arterial stiffness. We aimed to investigate associations between the serum klotho concentration and peripheral/central BP and arterial stiffness based on the carotid–femoral pulse wave velocity (cfPWV) in a Chinese population. We invited all inhabitants aged ≥ 18 years in two Dali communities for participation. The SphygmoCor system was used to record radial arterial waveforms. Aortic waveforms were derived using a generalized transfer function. The central BP was assessed by calibrating the brachial BP, which was measured using an oscillometric device. The serum klotho concentration was measured using an enzyme-linked immunosorbent assay and logarithmically transformed. Of the 716 participants (mean age: 51.9 ± 12.6 years), 467 (65.2%) were women. The median serum klotho concentration was 381.8 pg/mL. The serum klotho concentration did not significantly differ between patients with and without hypertension (P > 0.05) and between those with and without arterial stiffness (cfPWV ≥ 10 m/s) (P > 0.05). After adjusting for confounders, the serum klotho concentration was not significantly associated with the peripheral or central BP (P > 0.05) and cfPWV (P > 0.05). Our data indicated that the serum klotho concentration was not associated with BP or cfPWV in the general Chinese population.

This paper presents a free vibration analysis of functionally graded Reissner-Mindlin circular plates with various supported boundaries in thermal environments. A FGM consisting of metal and ceramic was considered in the study. Based on the geometric equation, physical equation and equilibrium equation of thick plate, taking into account the transverse shearing deformation, the free vibration equation of the axisymmetric FGM moderately thick circular plates was derived in terms of the middle surface angles of rotation and lateral displacement. The material properties of the plate were assumed to vary continuously in the thickness direction according a power law. By using shooting method to solve the coupled ordinary differential equations with different boundary conditions, the natural frequencies of FGM thick circular plates were obtained numerically. The effects of material gradient property, thickness ratio and boundary conditions on the natural frequencies were discussed in detail.

Vibration and post-buckling of beams made from functionally graded materials (FGM) subjected to uniformly and tangentially compressing follower forces are studied in this paper. Based on the accurately and geometrically nonlinear theory for extensible beams, the dynamic governing equations for FGM beams under non-conservative load are formulated. By using a shooting method to solve the non-linearly differential equations numerically, the responses of post-buckling and free vibration in the vicinity of post-buckling configuration are obtained, in which the hinged-fixed boundary conditions of beam are considered. Effects of material gradient parameter on the critical buckling, post-buckling and lower frequencies of the FGM beam are discussed in details.

Hydrothermal reaction of ZnSO 4 ·7H 2 O and 3-amino-1H-1,2,4-triazole (HATRZ) led to a three-dimensional zinc(II) coordination polymer, Zn 2 (ATRZ) 2 SO 4 ·3H 2 O ( 1 ). Compound 1 has been fully characterized by single crystal and powder X-ray diffraction, thermogravimetric analysis, infrared spectroscopy and elemental analysis. Single crystal X-ray diffraction reveals that 1 is a pcu -like network metal–organic framework which is constructed by a zinc(II)/ATRZ layer and a rarely reported inorganic sulfate pillar. Moreover, 1 shows characteristic ligand-centered fluorescence property.

In the present study, nonlinear bending problem of functionally graded material (FGM) cantilever beams resting on a Winkler elastic foundation under distributed load are discussed. Based on the large deformation theory and considering the axial extension of the beam, the equilibrium equations with geometric nonlinearity of FGM beams subjected to distributed load are established. In the analysis, it is assumed that the material properties of the beam vary continuously as a power function of the thickness. By using shooting method, the nonlinear boundary-value problem is numerically solved as well as the non-linear bending characteristic curves of the deformed beam versus the load are presented. The effects of material gradient property and foundation stiffness parameter on the bending deformation of the beam are discussed in detail.

Based on the accurate geometrical theory for the extensible elastic beams, an exact mathematical model of post-buckling transverse free vibration of Euler beams subjected to a distributed tangential follower force along the central axis are established. By using shooting method, pre-buckling free vibrations of both simply supported and fixed Euler beam are solved and the responses of small amplitude vibration are obtained. The numerical results show that all the frequencies of unbuckled beams decrease continuously with the increment of the load parameters.

Based on the large deformation theory and considering the axial extension of the beam, the governing equations of post-buckling of a simply supported elastic FGM beam subjected to conservative and non-conservative distributed forces were established. In the analysis, it was assumed that the material properties of the beam vary continuously as a power function of the thickness coordinate. By using shooting method, the nonlinear boundary-value problem was solved numerically and the equilibrium paths as well as the post- buckling configurations of the deformed beam were presented. A comparison between the results of conservative system and that of non-conservative systems were given. The results shows that the features of the equilibrium paths of the the functionally graded beam under non-conservative are evidently different from those to a conservative one.

Nonlinear bending problem of FGM cantilever beam under distributed load are discussed in this paper. Based on the large deformation theory and considering the axial extension of the beam, the equilibrium equations with geometric nonlinearity of a FGM beam subjected to distributed load are established. They consist of a boundary value problem of ordinary differential equations with strong non-linearity, in which seven unknown functions are included and the arc length of the deformed axis is considered as one of the basic unknown functions. By using shooting method and analytical continuation, the nonlinear boundary-value problem is numerically solved as well as the non-linear bending characteristic curves of the deformed beam versus the load are presented.

A novel three-dimensional (3-D) Dy(III)–Cu(I) heterometallic polymer, [Dy 2 (pca) 2 (npa) 2 (H 2 O) 3 ](Cu 2 I 2 ) ( 1 , pca = 2-pyrazinecarboxylic acid, npa = 1,8- naphthalenedicarboxylic acid), has been synthesized by hydrothermal reactions of Dy 2 O 3 , CuI, 2-pyrazinecarboxylic acid, 1,8-naphthalene anhydride in water in the presence of HClO 4 . Compound 1 has been characterized by elemental analysis, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analysis, respectively. The thermal stability and luminescence property of compound 1 have also been studied. Single crystal X-ray diffraction analysis reveals that compound 1 contains two distinct units of 1-D Dy–carboxyl belt and Cu–I chain. The two types of 1-D units are further linked via pca ligands to give a heterometallic Dy–Cu framework.

A new 3d–4fheterometallic polymer, poly[[aqua-μ3-chlorido-[μ3-4-(pyridin-4-yl)benzoato]tris[μ2-4-(pyridin-4-yl)benzoato]dicopper(I)erbium(III)] dihydrate], {[Cu2Er(C12H8NO2)4Cl(H2O)]·2H2O}n, was synthesized by the hydrothermal reaction of Er2O3, CuCl2·2H2O and 4-(pyridin-4-yl)benzoic acid in the presence of HClO4. The asymmetric unit contains one Er3+cation, two Cu+cations, one Cl−anion, four deprotonated 4-(pyridin-4-yl)benzoate ligands, one coordinated aqua ligand and two solvent water molecules. This tubular one-dimensional polymer is constructed from alternating clusters of europium(III)–water and copper(I) chloride bridged by 4-(pyridin-4-yl)benzoate ligands. Extensive hydrogen-bonding interactions involving both the coordinated and the solvent water molecules provide further stabilization to the structure.

Based on the large deflection theory for the extensible elastic beams, the governing equations of post-buckling of a cantilever elastic beam subjected to a non-conservative distributed tangential follower force along the central axis were established. They consist of a boundary value problem of ordinary differential equations with strong non-linearity, in which seven unknown functions were included and the arc length of the deformed axis is considered as one on the basic unknown functions. By using shooting method and analytical continuation, the nonlinear boundary-value problem was numerically solved as well as the post-buckling configurations of the deformed beam were obtained. The results show that the features of the equilibrium paths of the cantilever beam subjected to a non-conservative load are evidently different from those to a conservative one.

By using shooting method, large deflection bending of the Euler-Bernoulli beam with fixed-free ends subjected to a tip follower force is investigated. Based on geometrically non-linear theory for extensible elastic beams, the governing nonlinear governing equations of elastic beam subjected to a tip-concentrated follower force along the central axis are established. They consist of a boundary value problem of ordinary differential equations with strong non-linearity, in which seven unknown functions are included and the arc length of the deformed axis is considered as one of the basic unknown functions. By using shooting method and analytical continuation, the nonlinear boundary-value problem is numerically solved as well as the non-linear bending characteristic curves of the deformed beam versus the load are presented and the effects of load parameters on the deformation are also discussed. The results show that the load and the relevant physical quantities are evidently non-linearity.