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The successful development of highly sensitive, water‐compatible, nontoxic nanoprobes has allowed nanomaterials to be widely employed in various applications. The applicability of highly bright quantum dot (QD)‐based probes consisting of QDs on 120 nm silica nanoparticles (NPs) with silica shells is investigated. Their substantial merits, such as their brightness and biocompatibility, for effective bioimaging are demonstrated. Silica‐coated, QD‐embedded silica NPs (Si@QDs@Si NPs) containing QDs composed of CdSe@ZnS (core‐shell) are prepared to compare their structure‐based advantages over single QDs that have a similar quantum yield (QY). These Si@QDs@Si NPs exhibit approximately 200‐times stronger photoluminescence (PL) than single QDs. Cytotoxicity studies reveal that the Si@QDs@Si NPs are less toxic than equivalent numbers of silica‐free single quantum dots. The excellence of the Si@QDs@Si NPs with regard to in vivo applications is illustrated by significantly enhanced fluorescence signals from Si@QDs@Si‐NP‐tagged cells implanted in mice. Notably, a more advanced version of QD‐based silica NPs (Si@mQDs@Si NPs), containing multishell quantum dots (mQDs) composed of CdSe@CdS@ZnS, are prepared without significant loss of QY during surface modification. In addition, the Si@mQDs@Si NPs display a fivefold higher fluorescence activity than the Si@QDs@Si NPs. As few as 400 units of Si@mQDs@Si‐ NP‐internalized cells can be detected in the cell‐implanted mouse model.

This study examines the effect of the statistical/mathematical model selected and the variable set considered on the ability to identify financially troubled life insurers. Models considered are two artificial neural network methods (back-propagation and learning vector quantization (LVQ)) and two more standard statistical methods (multiple discriminant analysis and logistic regression analysis). The variable sets considered are the insurance regulatory information system (IRIS) variables, the financial analysis solvency tracking (FAST) variables, and Texas early warning information system (EWIS) variables, and a data set consisting of twenty-two variables selected by us in conjunction with the research staff at TDI and a review of the insolvency prediction literature. The results show that the back-propagation (BP) and LVQ outperform the traditional statistical approaches for all four variable sets with a consistent superiority across the two different evaluation criteria (total misclassification cost and resubstitution risk criteria), and that the twenty-two variables and the Texas EWIS variable sets are more efficient than the IRIS and the FAST variable sets for identification of financially troubled life insurers in most comparisons. Copyright The Journal of Risk and Insurance, 2006.

Satisfactory short- and mid-term results have been observed following microscopic decompression with tubular retractor (MDT) and conventional microscopic decompression (CMD) in lumbar spinal stenosis (LSS). It is not yet clear which surgical procedure is the optimal treatment for LSS, especially in long-term follow-up period. To the best of our knowledge, there is no comparative study analyzing the clinical-radiological outcomes of MDT and CMD over a 10-year follow-up periods. The purpose of this study was to evaluate and compare clinical and radiological outcomes of MDT and CMD over a 10-year follow-up period in patients with LSS. Of total 121 patients, 102 patients (53 MDT and 49 CMD) were followed for at least 10 years following MDT and CMD for LSS. We retrospectively reviewed surgical results and clinical outcomes based on the visual analogue scale, McNab's criteria, and the Oswestry Disability Index, and radiological analysis results with the parameters, including the change of disk height and intervertebral distance, obtained preoperatively and 3- and 6-month, and 1-, 6-, and 10-year postoperatively. There was no significant difference in patient demographics between the two groups. Five patients (two in MDT, three in CMD) required re-operation for re-stenotic change of the affected segment. The number of patients requiring re-operation was not significantly different between the two groups (p > 0.05). No statistically significant differences were observed between the groups in a long-term follow-up period after a 3-month follow-up (p > 0.05). However, in the acute postoperative phase of <3-month postoperatively, MDT appears to result in less postoperative pain and better clinical outcomes compared with the CMD. In conclusion, despite relatively small sample size with retrospective design, our study suggested that MDT appears to result in less postoperative pain and better clinical outcomes in the acute postoperative period of <3 months, but both MDT and CMD were no significant differences in clinical and radiological outcomes after that time.