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Surgeon experience certainly improves their technical efficiency although it also causes physiological changes with aging. The authors hypothesized that surgeons' technical efficiency improves with increasing experience up to a point where it then decreases, which is a concave relationship. The authors collected data from all the surgical procedures performed at University Hospital from April through September in 2013–19. The dependent variable was defined as surgeons' technical efficiency scores that were calculated using output-oriented Charnes–Cooper–Rhodes model of data envelopment analysis. Inputs were defined as (1) the number of assistants and (2) the duration of surgical operation. The output was defined as the surgical fee for each surgery. Surgeon experience was defined as the number of years since medical school graduation. Five control variables were selected: surgical volume, gender, academic rank, surgical specialty, and the year of surgery. Multiple regression analysis using pooled and random-effects Tobit models was performed for our panel data. Totally 20,375 surgical procedures performed by 264 surgeons in 42 months were analyzed. The coefficients of experience and the square of experience were not significantly different from zero. The other coefficients were also insignificant. Surgeons' technical efficiency does not have a concave relationship with experience. [ABSTRACT FROM AUTHOR]

Investigated the effects of text modification and task on incidental learning of foreign-language vocabulary by reading. The study focuses on how different cue types and a task would affect processing of input, initial learning, and retention of the meaning of target words. Results indicate that single and multiple-choice marginal gloss conditions performed significantly better than no cue and appositive conditions. (49 references) (Author/CK)

The presence of circulating tumor cells (CTCs) in the peripheral blood is associated with short survival, making the detection of CTCs clinically useful as a prognostic factor of disease outcome and/or a surrogate marker of treatment response. Recent technical advances in immunocytometric analysis and quantitative real-time PCR have made it possible to detect a few CTCs in the blood; however, there is no sensitive assay to specifically detect viable CTCs. Here, we report what we believe to be a new approach to visually detect live human CTCs among millions of peripheral blood leukocytes, using a telomerase-specific replication-selective adenovirus expressing GFP. First, we constructed a GFP-expressing attenuated adenovirus, in which the telomerase promoter regulates viral replication (OBP-401; TelomeScan). We then used OBP-401 to establish a simple ex vivo method that was able to detect viable human CTCs in the peripheral blood. The detection method involved a 3-step procedure, including the lysis of rbc, the subsequent addition of OBP-401 to the cell pellets, and an automated scan using fluorescence microscopy. OBP-401 infection increased the signal-to-background ratio as a tumor-specific probe, because the fluorescent signal was amplified only in viable, infected human tumor cells, by viral replication. This GFP-expressing virus-based method is remarkably simple and allows precise enumeration of CTCs., Introduction Determination of the extent of the disease is the most important factor in predicting the clinical outcome in cancer patients. Primary cancers have been known to shed tumor cells [...]

Currently available methods for detection of tumors in vivo such as computed tomography and magnetic resonance imaging are not specific for tumors. Here we describe a new approach for visualizing tumors whose fluorescence can be detected using telomerase-specific replication-competent adenovirus expressing green fluorescent protein (GFP) (OBP-401). OBP-401 contains the replication cassette, in which the human telomerase reverse transcriptase (hTERT) promoter drives expression of E1 genes, and the GFP gene for monitoring viral replication. When OBP-401 was intratumorally injected into HT29 tumors orthotopically implanted into the rectum in BALB/c nu/nu mice, para-aortic lymph node metastasis could be visualized at laparotomy under a three-chip color cooled charged-coupled device camera. Our results indicate that OBP-401 causes viral spread into the regional lymphatic area and selectively replicates in neoplastic lesions, resulting in GFP expression in metastatic lymph nodes. This technology is adaptable to detect lymph node metastasis in vivo as a preclinical model of surgical navigation., Author(s): Hiroyuki Kishimoto [1, 2]; Toru Kojima [1, 2]; Yuichi Watanabe [1, 3]; Shunsuke Kagawa [1, 2]; Toshiya Fujiwara [1, 2]; Futoshi Uno [1, 2]; Fuminori Teraishi [1, 2]; Satoru [...]

Optical materials for vacuum ultraviolet optics have attracted strong research interest as ArF excimer laser lithography of semiconductors has entered the practical application phase since 1996. A study was conducted to investigate ArF excimer-laser solarization in P-free and doped AlF3-YF3-RF2, R = alkaline earth metal, glasses by optical absorption and electron paramagnetic resonance spectroscopies. Results are discussed.