Pulmonary nodule size evaluation with chest tomosynthesis and CT: a phantom study.

OBJECTIVE: We compared digital tomosynthesis (TOMO) and chest CT in terms of assessing the sizes of nodules located in zones where evaluation by simple radiography is limited. METHODS: A total of 48 images comprising phantom nodules of four sizes in six different locations were used. Nodule size measurement errors for measurements using TOMO and CT images compared with the actual size from each observer were calculated. The inter- and intraobserver repeatability of the measured values and the agreement between the two techniques were assessed using the method described by Bland and Altman. RESULTS: The mean measurement errors for all of the nodules and four observers were -0.84 mm [standard deviation (SD), 0.60 mm] on TOMO and -0.18 mm (SD, 0.71 mm) on CT images. The mean measurement errors for the different observers ranged from -1.11 to -0.55 mm for TOMO and from -0.39 to 0.08 mm for CT. Assessing the agreement between nodule size measurements using TOMO and CT resulted in mean measurement errors of -0.65 mm, with a 95% limit of agreement of -2.53 to 1.22 mm for comparison of TOMO with CT. CONCLUSION: Our results suggest that nodule sizes obtained using TOMO and chest CT are comparable, even for nodules located in areas where the size measurement is limited on simple radiography. ADVANCES IN KNOWLEDGE: TOMO and CT can be used interchangeably, even for nodules located in a blind area on simple radiography.

Effects of growth pressure on the structural and optical properties of multi quantum wells (MQWs) in blue LED.

The effects of growth pressure in metal-organic chemical vapor deposition (MOCVD) on the structural and optical properties of InGaN/GaN multiple-quantum-wells (MQWs) grown on c-plane sapphire substrate were investigated by scanning transmission electron microscopy (STEM), atom probe tomography (APT), Raman spectroscopy and electroluminescence (EL) spectroscopy. As the growth pressure decreased, the growth rate of the InGaN layer increased, leading to a decrease in the frequency of the GaN A1(LO) mode peak and broadening of its full width half maximum (FWHM). The intensity of the EL spectra peaked at a growth pressure of 250 Torr with a narrow FWHM at high forward current. These optical properties are explained by either a high degree of compositional fluctuation of indium in the MQW and/or the high crystallinity of the InGaN layer due to the low growth rate under high pressure.

Reliability and validity of the Korean version of the manual ability classification system for children with cerebral palsy.

BACKGROUND: To investigate the inter- and intra-rater reliability of the Korean version of the Manual Ability Classification System (MACS) for children with cerebral palsy. METHODS: After a two-step forward and one-step backward translation, the inter-rater reliability of the Korean version of the MACS was assessed separately by parents, occupational therapists and physicians. A second assessment for intra-rater reliability was performed 4 weeks later. RESULTS: Sixty-nine children were enrolled. The intra-class correlation coefficients were 0.956 between occupational therapists and physicians, 0.927 between parents and physicians, and 0.960 between parents and occupational therapists. Intra-rater reliability ranged from 0.965 to 0.987. CONCLUSIONS: The Korean version of the MACS is reliable and valid and is suitable for assessing manual ability in Korean children with cerebral palsy.

The effects of RANTES/CCR5 promoter polymorphisms on HIV disease progression in HIV-infected Koreans.

Recent studies have reported that two single nucleotide polymorphisms (SNPs) in the RANTES gene promoter region, -403G/A and -28C/G, are associated with a slower rate of decline in CD4(+) T-cell number, whereas genetic polymorphisms within the CCR5 promoter are linked to acceleration of AIDS progression. In this study, we investigated the distribution of SNPs in the RANTES and CCR5 promoters and the association between these SNPs and HIV-1 disease progression in HIV-infected Koreans. Twenty-seven long-term non-progressors (LTNPs), 29 AIDS patients and 39 HIV-uninfected persons were enrolled in this study. SNPs for the RANTES and CCR5 promoters were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and a direct sequencing method. In the analysis of RANTES promoter polymorphisms, the genotypic and allelic frequencies of the RANTES -28G mutation were significantly lower in HIV-infected patients than in HIV-uninfected persons (P = 0.005 and P = 0.001, respectively). The genotypic frequencies of RANTES -28G and -403A mutations did not differ significantly between LTNPs and AIDS patients. The frequencies of three CCR5 promoter polymorphisms, designated 59029 G/A, 59353T/C, and 59402G/A, did not differ significantly between HIV-uninfected and HIV-infected patients. However, the allelic frequency of CCR559353C was significantly higher in AIDS patients than in LTNPs (P = 0.003). These results suggest that RANTES-28G and CCR5 59353C mutations might be associated with HIV infection or pathogenesis in the Korean population.

Mode-locked fiber laser gyroscope based on a distributed-feedback semiconductor laser amplifier.

A mode-locked fiber laser gyroscope is reported that uses a distributed-feedback semiconductor laser amplif ier as the gain medium. Stable mode-locked optical pulses were obtained without gain competition, and the pulse interval could be measured with much-improved accuracy as a function of rotation rate. The rms noise equivalent rotation rate was measured to be 0.4 deg/ radicalh.