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Design of a very large floating structure (VLFS) deployed near islands and reefs, different from those in the open sea, inevitably faces new technical challenges including numerical analysis methods. In this paper, a direct coupling analysis method (DCAM) has been established based on the Boussinesq equations and the three-dimensional hydroelasisity theory with Rankine source method to analyze the responses of a VLFS in shallow sea with complicated geographical environment. Model tests have been carried out to validate the DCAM. To further verify the numerical methods and investigate the performance of such a VLFS, a “Scientific Research and Demonstration Platform (SRDP)” was built and deployed in 2019 at the site about 1 000 m off an island with water depth around 40m in South China Sea. It is a simplified small model of a two-module semi-submersible-type VLFS. The numerical simulation of its responses on severe waves with focus on motions and connector forces is conduct by DCAM, and compared with the on-site measurements. Good agreement has been achieved. This approves the DCAM as a feasible tool for design and safety assessment of a VLFS deployed near islands and reefs.

The microstructure and cellular transition characteristics of an intermetallic Ti-42Al-3Nb-1Mo-0.1B (at.%) alloy were investigated. The as-cast microstructure of the alloy is mainly composed of (α2+γ) lamellar structure and (β+γ) mixture structure, which distributes along the boundaries of the lamellar colonies. In order to study the phase transformation of lamellar structure at aging temperature, a two-step heat treatment was carried out. After the first step of annealing treatment at 1,260 °C, the microstructure with relatively finer lamellar space and (γ+β/B2) mixture structure is obtained. Aging treatment, as the second heat treatment step, has significant influence on the microstructure, attributing to a cellular reaction of α2+γ→ γ+β. With the increase of aging temperature, the (α2+γ) lamellar structure continues to dissolve, whereas the contents of both the equiaxed γ and β/B2 grains continuously increase. Besides, the orientation of lamellae α2, equiaxed γ and equiaxed β/B2 in the cellular transition region follows a specific relationship of {0–11}ββ//{0001}α2α2//{1–11}γγ.

A dynamic model of a helical gear rotor system is proposed. Firstly, a generally distributed dynamic model of a helical gear pair with tooth profile errors is developed. The gear mesh is represented by a pair of cylinders connected by a series of springs and the stiffness of each spring is equal to the effective mesh stiffness. Combining the gear dynamic model with the rotor-bearing system model, the gear-rotor-bearing dynamic model is developed. Then three cases are presented to analyze the dynamic responses of gear systems. The results reveal that the gear dynamic model is effective and advanced for general gear systems, narrow-faced gear, wide-faced gear and gear with tooth profile errors. Finally, the responses of an example helical gear system are also studied to demonstrate the influence of the lead crown reliefs and misalignments. The results show that both of the lead crown relief and misalignment soften the gear mesh stiffness and the responses of the gear system increase with the increasing lead crown reliefs and misalignments.

The very large floating structure (VLFS) deployed near seashore, islands and reefs are always exposed to the extremely complex encountering waves. Traditional methods with homogeneous wave inputs are not applicable for the hydroelastic analysis of this type VLFS. In this paper, the authors carry out a numerical and experimental investigation on hydroelastic responses of an 8-module VLFS near a typical island. A direct coupling analysis method is established on the basis of the Boussinesq equation and RANKINE source method. The detailed theoretical derivation, numerical method and relevant calculation program THAFTS-BR are presented. Wave propagation near the island, motions and connector loads of the VLFS deployed a typical island are investigated based on the numerical method and model tests. Several useful conclusions are obtained, which can provide a reference for the analysis of dynamic responses, design and construction of the floating structures near islands and seashores.

This paper is concerned with the linear hydroelastic response of a pontoon-type very large floating structure (VLFS) in short-crested irregular waves. The linear potential theory is employed for the analysis of VLFS in frequency domain. To decouple the fluid–structure interaction, the higher-order boundary element method (HOBEM) combined with the finite element method (FEM) is adopted. VLFS is modeled as a Mindlin plate, and the mode superposition method is used to reduce the dimension of dynamic equations. The pseudo-excitation method (PEM) is adopted to analyze the stationary stochastic response of the floating structure. The efficiency of this new calculation scheme with the application of PEM is investigated in comparison with the conventional method for stochastic response by analyzing the computational complexity theoretically. Finally, the new calculation scheme is validated by comparing with the experimental data as well as the existing numerical results calculated in the conventional way. In addition, the efficiency of the present numerical approach is also testified which indicates that the proposed numerical scheme is time-saving.

The first author’s affiliation was no longer in use in the original version of the article and it should be replaced as follows: School of Mechano-Electronic Engineering, Xidian University, Xi’an 710071, China.

Many investigators have indicated that overexpression and amplification of matrix metalloproteinase 2 (MMP-2) and extracellular matrix metalloproteinase inducer (EMMPRIN) are independent prognostic factors for primary tumors. We studied expression of them in tissues from intrahepatic cholangiocarcinoma (IHCCA) and normal bile ducts, and discussed the occurrence and development of IHCCA. Another goal was to explore possible association of MMP-2 and EMMPRIN with clinicopathologic parameters and prognosis of IHCCA. MMP-2 and EMMPRIN expression in 106 cases of IHCCA tissues and 15 cases of normal bile ducts were examined by immunohistochemical staining. Then, the association of MMP-2 and EMMPRIN expression with clinicopathologic parameters and patients’ prognosis was analyzed. The positive expression levels of MMP-2 and EMMPRIN associated significantly with various clinicopathologic risk factors, such as poor histologic differentiation (p = 0.03, 0.02), higher TNM stages (p = 0.02, 0.01) and decreased tumor-specific survival. In particular, the tumor-specific survival rate of the patients with MMP-2+/ EMMPRIN+expression was the lowest (p < 0.01). Using Cox regression analysis of the 89 patients, the conjoined expressions of MMP-2-/ EMMPRIN-, MMP-2+/ EMMPRIN +, histologic differentiation, and the clinical TNM stages of tumorous tissues were independent prognostic indicators of IHCCA (p < 0.01, p < 0.01, p = 0.02, p = 0.01 and p = 0.01, respectively). MMP-2 and EMMPRIN expression in primary tumor predicts an unfavorable prognosis in IHCCA, suggesting a crucial role of the two markers in progression of human IHCCA.

To study the effect of alpha1-acid glycoprotein 1 (ORM1) polymorphism on the concentration of free nortriptyline in serum, genotyping analysis was employed in ORM1 by sequencing. Eighteen unrelated male adults were chosen and given a single dose of 25 mg nortriptyline orally, then the blood samples were taken at 0, 1, 2, 3, 4, 6, 8, 12, 24, 32, 48, 72, 96 and 168 hours after drug administration. Nortriptyline and 10-OH-nortriptyline in serum and ultrafiltrate were detected for the total and free concentration by using HPLC-MS/MS. Pharmacokinetic parameters were compared among different ORM1 genotypes. No significant differences were shown in the pharmacokinetic parameters of total nortriptyline and 10-OH-nortriptyline. The mean AUC(0-infinity) of free nortritpyline in ORM1 * F/ * F1 subjects was significantly higher than that in ORM1 * F1/ * S and ORM1 * S/ * S subjects [(119.1 +/- 74.4) ng x mL(-1) x h vs (51.4 +/- 23.2) ng x mL(-1) x h and (42.4 +/- 11.6) ng x mL(-1) x h]. The percentage of protein binding in subjects with ORM1 * F1/ * F1 genotype at 2, 3, 4, 6, 8 and 12 h after administration was slightly lower than in those with ORM1 * F1/ * S and ORM1 * S/ * S genotypes while the distinct difference was shown at 4 h (P0.05). Different ORM1 genotypes might affect the protein binding percentage and the concentration of serum free nortriptyline. The ability binding to the drug was higher in subjects with ORM1 * S/ * S genotype than in those with other two genotypes, so as to cause the lower concentration of free nortriptyline.

Objective: To analyze the relationship between the result of electro interstitial scan and the level of male uric acid. Methods: The electro interstitial scan tests were done among 959 males who conducted health examination and came from Shandong,and the levels of uric acid were also tested. Results ： There was a linear correlation between the result of uric acid and the electro interstitial scan. Conclusion: The electro interstitial scan can predict hyperuricemia in some people.

BACKGROUND: The presence of food-specific IgG antibodies in human serum may be useful for diagnosis of adverse food reactions. However, the clinical utility of testing for such antibodies remains very controversial. The aim of this study was to evaluate the serum levels and population distribution of food-specific IgGs and their association with chronic symptoms in a large-scale Chinese population. METHODOLOGY/PRINCIPAL FINDINGS: A total of 21305 adult participants from different regions of China had 14 type of food-specific serum IgG antibodies that were measured by enzyme-linked immunosorbent assay. Among these, 5,394 participants were randomly chosen to complete follow-up questionnaire surveys on their dietary characteristics and chronic symptoms. The concentrations of food-specific IgGs against 14 foods ranged from a median (interquartile range) of 7.3 (3.8, 12.6) U/mL of pork-specific IgG to 42.3 (28.8, 60.2) U/mL of crab-specific IgG. The concentration of food-specific IgGs was closely related to gender; after adjustment for region and age, women had higher concentrations of food-specific IgGs against all of the 14 foods except chicken (regression coefficient (95% CI): 0.01 (-0.003, 0.023); P = 0.129) and corn (0.002 (-0.013, 0.016); P = 0.825). Similar results were also found in the relationship of geographic region to the food-specific IgG concentrations for the 14 foods. Chronic symptoms were negatively associated with the concentrations of a few food-specific IgGs, and were positively associated with the concentrations of other food-specific IgGs. CONCLUSIONS: The levels of food-specific IgGs were variable both in healthy and in symptomatic Chinese adults. These findings raise awareness that demographic factors, the type of food and specific chronic symptoms should be considered before food elimination treatment based on IgG testing in patients with chronic symptoms is used in clinical practice.