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An improved component modal synthesis-based nonproportional mistuning method (ICMS-NPMM) is proposed to investigate mistuned turbine blisks (MTBs) since the high-fidelity finite element models (HFEMs) involve large number of computations, which leads to low calculation efficiency. To reduce degrees of freedom and suppress the flutter of MTB, it is divided into mistuned blade structure and tuned disk structure, and the intentional mistuning is considered. Furthermore, the mistuned parameters, nonproportional mistuning, and complex loads are also considered. Firstly, the basic theory of ICMS-NPMM is investigated; secondly, the model of MTB is established via ICMS-NPMM; finally, the intentionally mistuned design of modal shape amplitudes (MSAs) is investigated via ICMS-NPMM. The results indicate that the calculation efficiency is enhanced via ICMS-NPMM relative to that of via HFEM. In addition, the sensitivity and the flutter are decreased; meanwhile, the amplitude fluctuations of MSAs are distinctly decreased and become comparatively smooth. This investigation provides an important guidance for the vibration characteristic study of complex mechanical structures in engineering practice. [ABSTRACT FROM AUTHOR]

Background/Aims: Gastric signet ring cell carcinoma (GSRC), a subtype of adenocarcinoma, has been considered a histological type with poor survival. We aimed to compare the survival outcomes between patients with GSRC and patients with gastric non-signet ring cell adenocarcinoma (NGSRC) and constructed a nomogram to predict gastric adenocarcinoma-specific survival (GCSS). Patients and Methods: We identified 10,031 patients with gastric adenocarcinoma (GA) from the surveillance, epidemiology, and end results (SEER) database and stratified them into two histological type groups: GSRC and NGSRC. We used propensity score matching and identified 4304 patients (training cohort) to assess the effect of the histological type on GCSS with Kaplan–Meier curves, and constructed a predictive nomogram. The accuracy of the nomogram was tested on the remaining 5727 patients (validation cohort) with concordance index (C-index) values, calibration curves, and receiver operating characteristic (ROC) curve analysis. Results: We found that the histological type SRC was not associated with significantly poor survival (5-year survival rate: 46.1% vs 46.7%, P = 0.822). GSRC patients had similar GCSS rates compared to those with NGSRC in each tumor, node, and metastasis (TNM) stage (allP > 0.05). The nomogram showed that histological type was a relatively weak predictor of survival. The C-index value of the nomogram for predicting survival was 0.720, similar to that in the validation cohort (0.724). Conclusions: Patients with GSRC had a similar prognosis to those with NGSRC. The proposed nomogram allowed a relatively accurate survival prediction for operable GA patients after gastrectomy. [ABSTRACT FROM AUTHOR]

Abstract: Ecological engineering was carried out in Meiliang Bay of Lake Taihu beginning in 2003 in order to improve water quality. There were two main objectives: to improve the growth environment for macrophytes, and to restore macrophyte assemblages. We examined surface sediments once per month beginning in April 2005 to study the response of sediment nutrient content to the ecological engineering. Average total nitrogen (TN) and total phosphorus (TP) concentrations in the surface sediments were 7043 and 1370mgkg−1, respectively, in May 2005, while after 1 year, TN concentration was reduced to 2929mgkg−1 and TP concentration was reduced to 352mgkg−1. We conclude that ecological engineering can lower the nutrient content in surface sediments when it is used to improve water quality. [Copyright &y& Elsevier]

Abstract: The Cr, Zn, Cu, Cd, Pb contents were determined in Cyprinus carpio Linnaeus, Carassius auratus Linnaeus, Hypophthalmichthys molitrix and Aristichthys nobilis, which were caught from Meiliang Bay, Taihu Lake, a large, shallow and eutrophic lake of China. The results showed that: (1) the Cr, Cu, Pb, Cd contents in the edible parts of the four fish species were much lower than Chinese Food Health Criterion (1994), but the Zn contents were higher than the Criterion; (2) Cd contents were the highest in the liver of fish, Pb contents were almost the same in all organs of fish, Cr contents mainly enriched in the skin and gonads, Zn contents were the highest in the gonad (♀), and Cu contents were the highest in the liver; (3) the total metal accumulation was the greatest in the liver and the lowest in the muscle. The total metal accumulation was the highest in C. auratus L. This investigation indicated that fish products in Taihu Lake were still safe for human consumption, but the amount consumed should be controlled under the Chinese Food Health Criterion to avoid excessive intake of Zn. [Copyright &y& Elsevier]

Investigation was made into sediment depth at 723 irregularly scattered measurement points which cover all the regions in Taihu Lake, China. The combination of successive correction scheme and geostatistical method was used to get all the values of recent sediment thickness at the 69 × 69 grids in the whole lake. The results showed that there is the significant difference in sediment depth between the eastern area and the western region, and most of the sediments are located in the western shore-line and northern regimes but just a little in the center and eastern parts. The notable exception is the patch between the center and Xishan Island where the maximum sediment depth is more than 4.0 m. This sediment distribution pattern is more than likely related to the current circulation pattern induced by the prevailing wind-forcing in Taihu Lake. The numerical simulation of hydrodynamics can strong support the conclusion. Sediment effects on water quality was also studied and the results showed that the concentrations of TP, TN and SS in the western part are obviously larger than those in the eastern regime, which suggested that more nutrients can be released from thicker sediment areas. [ABSTRACT FROM AUTHOR]

In this paper, downward movement of phosphorus and copper as dredged sediment applied on sandy loam soil was studied by column leaching experiments. Three sediment application rate, (i.e., 1, 2 and 5-cm depth of sediments) were applied to the top of the soil columns. Two and a half months leaching experiments were conducted, which include a 15-day un-watered period. Concentrations of phosphorus and copper in the leachate and the vertical distribution of Olsen-P and diethylenetriaminepentaacetic acid (DTPA) extractable Cu in the soil columns were determined. The results showed that, un-watered period could increase the downward movements of phosphorus and copper. Sediment application significantly increased Olsen-P concentration in the top 15 cm of the soil columns, but has not significantly affected that in the deeper soil layer. The 1-cm depth sediment treatment did not increase the DTPA extractable Cu concentration in the whole soil column. The 5-cm depth sediment treatment, however, significant increased the DTPA extractable Cu in the deeper soil layers. This study suggested that the application of dredged sediment laden with P and Cu on sandy loam soil might cause the significant downward movement of phosphorus and copper. [Copyright &y& Elsevier]