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Fluorinated ethylene propylene (FEP) wire insulation ignition is investigated in a forced flow field in microgravity and normal gravity with a continuous current. First, FEP insulation melts and decomposes, causing jet bursting in both normal gravity and microgravity. Second, the forced flow and gravity produce minor effects on the core heating and bursting time, while the pyrolysis time increases slightly with increasing air velocity. Third, the positively stretch rates in terms of the velocity gradients are higher in microgravity. Both the forced flow and gravity have significant effects on the induction time, which is dependent on the stretch rate and Damköhler number. The induction time increases with increasing air velocity, and it is higher in microgravity. Finally, the ignition delay time is dominated by the core heating and bursting time, while its bigger value and faster increase in microgravity with increasing air velocity are dominated by the induction time. [ABSTRACT FROM AUTHOR]

Many industrial combustion devices rely on jet flame combustion in the crossflow to achieve mixing and reaction. Previous research offers a limited predictive capability regarding the coupling effects of the crossflow and jet flow on the flame radiative fraction. In this work, a new theoretical equation is derived to relate the radiative fraction to the fuel flow rate and the crossflow velocity. The experimental results show that the flame length increases as the crossflow velocity increases for all considered flames. The results of this work suggest that the stretching factor is 0.08 s. The radiative fraction is almost independent of the nozzle diameter in the case of a low crossflow velocity. The crossflow has the strongest effect on the radiative fraction for a smaller nozzle diameter. This is because of the effect of the crossflow and jet flow velocities on the soot residence time, which is proportional to the radiative fraction. [ABSTRACT FROM AUTHOR]

AimsTo investigate the cytotoxicity of beta-lapachone, a potent agent that may selectively target tumour cells, in retinoblastoma (RB) cell lines.MethodsGrowth inhibitory effects of beta-lapachone were evaluated in Y79, WERI-RB1, and RBM human retinoblastoma cell lines. Pro-apoptotic effects of beta-lapachone were evaluated in Y79 cells by detection of caspase 3/7 activity, by enzyme-linked immunosorbent assay for nucleosome fragments, and by cellular morphological analysis.ResultsBeta-lapachone induced significant dose-dependent growth inhibitory effects in all three retinoblastoma cell lines. The 50% growth inhibitory concentration (IC50) of this agent was 1.9 μM in Y79 cells, 1.3 μM in WERI-RB1 cells, and 0.9 μM in RBM cells. Beta-lapachone also induced proapoptotic effects in RB cells. Treatment of Y79 cells with 1.9 μM beta-lapachone (IC50) resulted in a peak, fourfold induction of caspase 3/7 activity at 72 h post-treatment; a peak, 5.6-fold increase in nucleosome fragments at 96 h post-treatment; and a peak, 1.7-fold increase in the frequency of apoptotic cells at 48 h post-treatment, relative to vehicle-treated controls.ConclusionBeta-lapachone induced potent cytotoxic effects in RB cell lines at low micromolar concentrations, suggesting this agent could be useful in the clinical management of RB.Eye (2008) 22, 454–460; doi:10.1038/sj.eye.6702764; published online 16 March 2007 [ABSTRACT FROM AUTHOR]

A case of type I (type A) aortic dissection proved by postmortem examination could not be fully delineated relative to the type of dissection by dynamic CT as well as three positive contrast aortograms. Small tears in the ascending aorta and their strategic locations can escape even intensive radiologic evaluation. We present a case in which medical therapy was provided and, inappropriately, surgery was not performed. [ABSTRACT FROM AUTHOR]

Lymphomatoid granulomatosis (LYG) is a rare angiodestructive lymphoproliferative disorder (LPD) of uncertain etiology, with prominent pulmonary involvement. Recent studies indicate that LYG is an Epstein–Barr virus (EBV)-associated B cell LPD with large numbers of background reactive T lymphocytes (T cell-rich B cell lymphoma). Although the disease frequently, but not exclusively, occurs in various immunodeficiency states, it has not been reported in association with the transient immunosuppression following autologous bone marrow/peripheral stem cell transplantation (ABM/PSCT). We describe a patient who developed lymphomatoid granulomatosis of the lung approximately 2 weeks after high-dose chemotherapy and autologous peripheral stem cell transplantation for multiple myeloma. Although molecular studies showed no evidence of EBV genome in the biopsy material, the serologic profile with high IgM titers was suggestive of primary EBV infection. Complete radiologic remission occurred following reconstitution of the patient’s immune response after a 2-week course of ganciclovir treatment. Despite the apparently low frequency of LPD (both LYG and EBV-associated post-transplant lymphoma) in the ABMT setting, we believe that it should be considered in the differential diagnosis of patients whose clinical course following ABMT is complicated by fevers, in the absence of an identifiable infectious process. [ABSTRACT FROM AUTHOR]

The atypical appearance of a gas-containing, noninfected, popliteal synovial cyst has been presented. The case again demonstrates the value of plain radiographs, in this instance in distinguishing gas bubbles and calcification, which may not be apparent by MRI and ultrasound. The uniqueness of this case is stressed. The cause of the gas bubbles was not ascertained. [ABSTRACT FROM AUTHOR]

The development of a right hemothorax as the result of a ruptured thoracoabdominal aneurysm is an uncommon and usually fatal event. Survival depends upon an accurate diagnosis and prompt surgical intervention. We present a case of a ruptured thoracoabdominal aneurysm into the right chest that presented as opacification of the right hemithorax and hypotension. An early CT scan provided the correct preoperative diagnosis, although the patient did not survive. [ABSTRACT FROM AUTHOR]