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In this work, we focus on assessing the group effect of localized corrosion on the ultimate strength of the marine structural plates and study the load-deformation behaviors of plates of various slenderness and uniaxial compression. Meanwhile, we investigate different corroded patterns from a single circular pit to 25 circular pits distributed over the plate and carry out hundreds of nonlinear finite element simulations by combining the number, depth, distribution of pits with imperfections and slenderness of plate. The distribution of multiple pits causes scattering of stress concentration on the plate, then the plastic section of plate changes with wider distribution of damage simultaneously. The ultimate strength arises when un-loading zone comprised of the yielding strips and holes extends across the plate. It can be concluded that the corroded condition defined as group effect of pits manipulates the deformation state and the loading capacity of plate at the ultimate strength mode that coincides with the proportion of effective loading area and section in the process of post-buckling. To validate the effect of pits group, we perform the numerical experiments of the post-buckling of steel plates containing pits in a row with different orientation.

Objective. To investigate the effect of intensive management and achieving the target control more than 3 times on endpoint events during 9 consecutive years’ annual assessment in type 2 diabetes (T2DM) patients in the Sanlitun Community Health Service Center in Beijing, including blood glucose, blood pressure, lipids profiles, and the joint target control. Methods. In Beijing Community Diabetes Study (BCDS), 224 patients with T2DM from the Sanlitun Community Health Service Center were enrolled in 2008. All patients were randomly assigned to the intensive management group (n = 113) and the standard management group (n = 111). All patients were followed up for nine consecutive years from January 2009 to December 2017. Systolic blood pressure (SBP), diastolic blood pressure (DBP), glycosylated hemoglobin (HbA1c), and low-density lipoprotein cholesterol (LDL-C) were detected as the main indexes, and the endpoint events were also carried out at the same time. The endpoint events were analyzed by using survival analysis (Kaplan–Meier method) based on management grouping and whether achieving the target control more than 3 times or not. Results. During the nine-year follow-up, the abscission number was 35 (14.29%), among which 14 (12.39%) was in the intensive management group and 21 (18.92%) was in the standard management group. The incidence of diabetic retinopathy (6 cases, 5.41%) and diabetic nephropathy (13 cases, 11.71%) in the standard management group was significantly higher than that in the intensive management group (1 case, 0.88%; 5 cases, 4.42%), respectively (P<0.05). However, there were no significant differences on the other endpoint events between the two groups (P>0.05). All-cause death was 23 cases, in which patients who achieved the target control (HbA1c and LDL-C) and the joint target control more than 3 times were significantly lower than that of less than 3 times (P<0.05). As far as death caused by cardiovascular events, cerebrovascular events, and newly onset coronary heart disease are concerned, there were no significant differences on the aforementioned endpoint events between the two groups based on target control more than 3 times or not (P>0.05). There were less incidence of new onset cerebrovascular events, stenosis or occlusion of large arteries, and diabetic microvascular complications in patients who achieved target control (HbA1c and LDL-C) and the joint target control more than 3 times than those with target control less than 3 times (P<0.05). Conclusions. The intensive management can effectively reduce the occurrence of microvascular complications. The incidence of all-cause death and the other endpoint events decreased in T2DM patients who achieved the joint target control more than 3 times during the nine-year management, which improved survival time and life quality. This trial is registered with ChiCTR-TRC-13003978 and ChiCTR-OOC-15006090.

A theoretical research is carried out to study the large deflection response of a fully clamped rectangular metal sandwich plates with functionally graded foam core subjected to blast loading. Using a new yield criterion for sandwich cross-section with graded foam core, we obtained the analytical solutions for the dynamic response of rectangular sandwich plates. Finite element simulations with gradient layers foam core model are performed to study the dynamic response of the sandwich plates with graded foam core subjected to blast loading. The results of the analyses seem to predict well the deflections that are given numerically.

In this study, the Raman and fluorescence spectra of LaCl3 solution were studied with theoretical calculation and spectroscopic experiments. Based on B3LYP method of density functional theory, with the 6-31G(D,P)+Def2-SV (P) based on the group level the lanthanum chloride solution of micro cluster structure is calculated. The results show that the micro cluster molecules tend to form a 9 coordination structure, which verifies the feasibility of the method. Theoretical and experimental Raman values are compared to the basic consistent. The addition of LaCl(3) leads to the increase of the peak intensity of the Raman spectra in the 300~600 cm-1 range, which may be caused by the superposition of the La-O vibration and the rocking peaks of O—H in aqueous solutions; In the 3 000~4 000 cm(-1) range, the peak of lanthanum chloride solution is narrow compared with water, which may be caused by the stretching vibration of O—H in lanthanum hydrate. Fluorescence emission spectra at 350 nm appear obvious new peak, the good linearity was obtained between the peak intensity and the concentrations, and a rapid method for the quantitative analysis of lanthanum chloride solution from the angle of the complex is also realized. On the same basis set level calculated fluorescence emission center of clusters, in the range of allowable error, the theoretical calculation and the experimental spectra are basically consistent, and the new peak of the experimental spectra are identified.

In this paper the cluster structures of [Zn-(CH3CH2OH)n]2+ have been investigated with spectroscopic experiment and theoretical calculation. According to the fluorescence spectroscopy experiments, the fluorescence peak of ethanol molecules was found between 275~330 nm. A new peak appeared between 350~380 nm after the metal ions (Zn2+) was added into ethanol solution due to the generation of new clusters of molecules, and the original fluorescence peak of ethanol molecules became weak owing to the destroyed structure of ethanol molecules induced by Zn2+. The cluster structures of Zn2+ in water solution were investigated by using different methods. By comparing the results, a more accurate and fast B3LYP method of DFT was found and applied to optimize the possible structures of [Zn-(CH3CH2OH)n]2+. The results suggested that the first solvation shell of the system is up to six ethanol molecules, and thermodynamic parameters also shows the six kinds of molecular clusters which are likely in the solution. Moreover compared the theoretical fluorescence spectroscopy with experimental fluorescence spectroscopy, new clusters [Zn-(CH3CH2OH)n]2+ have been generated, with [Zn-(CH3CH2OH)n]2+(n=1~3) as main constructions.

Computer simulation of cylindrical shell subject to lateral impact by rigid projectile is carried out. The effects of three kinds of typical rigid projectiles, geometric parameters of cylindrical shell and constraint conditions on critical speed are analyzed. The results indicate that the shape of projectile and size of cylindrical shell have a great influence on penetration, and the tapered projectile has a minimum critical speed. The influence of constraint conditions on penetration has a great relationship with thickness of cylindrical shells; energy distribution varies with different thickness of cylindrical shells.

Changhua Stone is a rock, composed of clay minerals such as dickites and is also a special secondary quartzite formed by gas liquid metasomatic metamorphism. The article emphasizes its study on rock characteristics, mineral composition, and the causes of formation of Changhua Stone, excluding Changhua Chicken-Blood Stone. By observing petrographical characters of Changhua Stone, analyzing its physical and chemical characters, and testing its geochemical compositions with SEM and X-ray diffraction analysis, the results indicate that the mineral compositions of Changuan Stone are relate to the composition of protolith, the compositions and characters of metasomatic metasomatic fluid, and the conditions of metamorphism, especially the stress and the temperature.

†Background and Aims Soil microbes have been demonstrated to play an important role in favouring plant iron (Fe) uptake under Fe-limiting conditions. However, the mechanisms involved are still unclear. This present study reported the effects of plant Fe status on the composition of siderophore-secreting microbes in the rhizosphere, and their potential function in improving plant Fe nutrition. †Methods AnFe-efficientplant,redclover(Trifoliumpratense‘Kenland’)wasculturedinacalcareoussoiltoobtain rhizosphere soils with (Fe-sufficient) or without (Fe-stressed) foliar FeEDTA spraying. The siderophore-producing ability of rhizospheric microbes was measured. The bioavailability of the siderophore-solubilized Fe from iron oxides/hydroxides was tested in hydroponic culture. †Key Results In rhizosphere soil, the number of microbes that secreted siderophores quickly was more in the Festressed treatment than in the Fe-sufficient one, while the number of microbes that did not secret siderophores was the opposite. A significantly higher concentration of phenolics was detected in the rhizosphere soil of Fe-stressed plants. Moreover, after the soil was incubated with phenolic root exudates, the composition of the siderophoresecreting microbial community was similar with that of the rhizosphere of Fe-stressed plant. Additionally, the siderophores produced by a rhizospheric microbe isolated from the Fe-stressed treatment can well solubilize iron oxides/hydroxides, and the utilization of the siderophore-solubilized Fe by plant was even more efficient than EDTA-Fe. †Conclusions Iron-deficiency stress of red clover would alter the composition of siderophore-secreting microbes in the rhizosphere, which is probably due to the phenolics secretion of the root, and may in turn help to improve the solubility of Fe in soils and plant Fe nutrition via elevated microbial siderophore secretion.

A patient with severe hypertriglyceridemia and recurrent pancreatitis was found to have significantly decreased lipoprotein lipase (LPL) activity and normal apolipoprotein C-II concentration in post-heparin plasma. DNA analysis of the LPL gene revealed two mutations, one of which was a novel homozygous G-->C substitution, resulting in the conversion of a translation initiation codon methionine to isoleucine (LPL-1). The second was the previously reported heterozygous substitution of glutamic acid at residue 242 with lysine (LPL-242). In vitro expression of both mutations separately or in combination demonstrated that LPL-1 had approximately 3% protein mass and 2% activity, whereas LPL-242 had undetectable activity but normal mass. The combined mutation LPL-1-242 exhibited similar changes as for LPL-1, with markedly reduced mass, and for LPL-242, with undetectable activity. These results suggest that the homozygous initiator codon mutation rather than the heterozygous LPL-242 alteration was mainly responsible for the patient phenotypes.

Aluminium (Al)-induced secretion of organic acids from plant roots is considered a mechanism of Al resistance, but the processes leading to the secretion of organic acids are still unknown. In the present study, a protein-synthesis inhibitor, cycloheximide (CHM), was used to investigate its effect on Al-induced organic acid secretion in a pattern I (rapid exudation of organic acids under Al stress) plant buckwheat (Fagopyrum esculentum Moench) and a pattern II (exudation of organic acids was delayed by several hours under Al stress) plant Cassia tora L. A dose-response experiment showed that the secretion of oxalate by buckwheat roots was not affected by CHM when added in the range from 0 to 50 microM, with or without exposure to 100 microm Al, but the secretion of citrate was completely inhibited by 30 microM CHM in C. tora. A time-course experiment showed that even prolonged exposure to 20 microM CHM did not affect oxalate secretion in buckwheat, but significantly inhibited citrate secretion in C. tora. However, citrate synthase (CS) activity in C. tora was not affected during 12 h exposure to 100 microM Al when compared with that in control roots, although CHM can inhibit CS activity effectively. These results indicated that CS activity was not related to Al-regulated citrate efflux in C. tora. The total protein was decreased by 14.0% and 32.3% in C. tora and buckwheat root tip, respectively, after 3-h treatment with 20 microM CHM. A 3-h pulse with 20 microM CHM completely inhibited citrate efflux in C. tora during the next 6-h exposure to Al, although a small amount of citrate was exuded after 9-h exposure. However, oxalate efflux in buckwheat was not influenced by a similar treatment. In buckwheat, a 3-h pulse with 100 microM Al maintained oxalate secretion at a high level during the next 9 h, with or without CHM treatment. Conversely, in C. tora a 6-h pulse with 100 microM Al induced significant secretion of citrate which was inhibited by the CHM. Taken together, these findings suggest that both de novo synthesis and activation of an anion channel are needed for Al-induced secretion of citrate in C. tora, but in buckwheat the plasma membrane protein responsible for oxalate secretion pre-exists.

Oxalic acid secretion from roots is considered to be an important mechanism for aluminum (Al) resistance in buckwheat (Fygopyrum esculentum Moench). Nonetheless, only a single Al-resistant buckwheat cultivar was used to investigate the significance of oxalic acid in detoxifying Al. In this study, we investigated two buckwheat cultivars, Jiangxi (Al resistant) and Shanxi (Al sensitive), which showed significant variation in their resistance to Al stress. In the presence of 0 to 100 μ m Al, the inhibition of root elongation was greater in Shanxi than that in Jiangxi, and the Al content of root apices (0–10 mm) was much lower in Jiangxi. However, the dependence of oxalic acid secretion on external Al concentration and the time course for secretion were similar in both cultivars. Furthermore, the variation in Al-induced oxalic acid efflux along the root was similar, showing a 10-fold greater efflux from the apical 0- to 5-mm region than from the 5- to 10-mm region. These results suggest that both Shanxi and Jiangxi possess an equal capacity for Al-dependent oxalic acid secretion. Another two potential Al resistance mechanisms, i.e. Al-induced alkalinization of rhizosphere pH and root inorganic phosphate release, were also not involved in their differential Al resistance. However, after longer treatments in Al (10 d), the concentrations of phosphorus and Al in the roots of the Al-resistant cultivar Jiangxi were significantly higher than those in Shanxi. Furthermore, more Al was localized in the cell walls of the resistant cultivar. All these results suggest that while Al-dependent oxalic acid secretion might contribute to the overall high resistance to Al stress of buckwheat, this response cannot explain the variation in tolerance between these two cultivars. We present evidence suggesting the greater Al resistance in buckwheat is further related to the immobilization and detoxification of Al by phosphorus in the root tissues.

Raman spectra of aluminosilicate minerals, namely kyanite, andalusite, and sillimanite and K2O-Al2O3-SiO2 glasses were recorded. Four alumino-silicon tetrahedral model clusters were calculated by self-consistent (SCF) molecular orbital ab-ini-tio calculation of the quantum chem (QC) method. The result shows a decrease tendency in Raman frequencies in the 800-1200 cm(-1) frequency region with increase in four-coordinated Al content, which is assigned to the Si--Onb symmetry stretching vibrations. The Raman spectra in the 700-800 cm(-1) frequency region is attributed to Al-Onb symmetry stretching vibrations.

When the beam theory was used to calculate ship hull vibration, greater discrepancies were found between theoretical calculations and actual measurements especially at higher modes. Thus the beam model cannot be considered as a practical one for higher-mode calculations. This paper presents the application of two-dimensional finite element model for the calculation of ship vertical vibration. Using the multi-element structural dynamic analysis program DDJ(DL) developed by ourselves, the hull vibration analysis of two ships (vessel A and vessel B) was carried out on the Model-709 Computer made in the People's Republic of China.