Effective mechanisms of ATX-S10, a new photosensitizer, on HeLa tumors in nude mice

Photodynamic therapy (PDT) is a treatment modality that utilizes a photosensitizing drug activated by laser generated light. PDT is effective for oncologic applications. Many cancer patients have undergone a hematoporphyrin derivative (HpD)-mediated PDT. The HpD showed a side effect causing prolonged cutaneous photosensitivity. But ATX-S10, a new photosensitizer, provides rapid plasma and tissue clearance, comparable photoactivation efficiency, and superior light absorption of visible red. In this study, the tumor rejection mechanisms of PDT using ATX-S10 on HeLa tumors in nude mice were investigated with morphological and fluorometric methods. The mice were intracutaneously inoculated with HeLa cells, 5 x 10(5) or 1 x 10(7) cells. When tumors grew to about 10-12 mm in diameter, mice were intraperitoneally administered ATX-S10, 30 mg/kg, and 2 hours later the ATX-S10 in tumors was indirectly measured by a fluorometric machine, PMA-10 (Hamamatsu Photonics K. K.) and the tumors were irradiated by Optical Parametric Oscillator (Hamamatsu Photonics K. K.) tuned to a wave length at 670 nm, 5 mJ/pulse, 100 J/tumor. Before and after the irradiation, the effective mechanisms of PDT with ATX-S10 were studied by histological and ultrastructural approaches. The results showed occlusive thrombi in the microvasculature of the tumors and tumor cell death. These occlusive thrombi were observed within one hour after PDT at both light and electron microscopy levels, and were more remarkable as time passed after PDT. Therefore, the morphological studies of PDT with ATX-S10 suggested that the rejection mechanisms occurred mainly as a result of the destructive changes of the microvasculature in the tumors first, and secondly or simultaneously, tumor cells were destroyed through necrosis, and finally the tumors were rejected.     

The rise and fall of an executive information system: a case study

The progress of an executive information system project within a manufacturing organization over a period of 9 years is described. The case study illustrates the importance of the interaction between the business environment, the organizational environment and the perceptions and interpretations of events and facts by stakeholders on the success or failure of an information system. It shows the importance of context in the development and implementation of an executive information system and the dynamic nature of the influence of social, economic and technical factors. The reasons for the initial success and the subsequent failure of the EIS within the company are explored from a contingency perspective.     

Safety implications of control systems

As part of an overall program to determine the extent to which failures of control can impact plant safety, control failures in the Oconee-1 nuclear plant were examined. Plant systems capable of initiating plant overcooling and undercooling were identified, as well as those with potential for overfilling events in the steam generators. Failure mode and effects analyses (FMEA) were conducted on these candidate plant systems, with computer analysis applied where appropriate. This latter process utilized a detailed hybrid computer model of Oconee-1, developed as part of this program. Where failures with safety consequences were found, probabilities of the pertinent scenarios were developed. Tentative recommendations for corrective actions have been sought.     

Rumination and psychological distress among bereaved partners.

Recently bereaved men who evidenced more negative ruminative thoughts in free-response interviews showed greater psychological distress on several outcome measures both 1 month and 12 months after their loss and less increase in positive morale over this 12-month period. Men who engaged in more analysis of themselves and the meaning of their loss reported greater positive morale 1 month after their loss but showed more persistent depression and absence of positive states of mind over the 12 months following their loss. Finally, men who reported more social friction also evidenced more enduring depressive symptoms over the year than did men who reported less social friction. These results are generally consistent with other studies that have shown that self-reflective, ruminative coping with negative emotions and social friction are associated with longer and more severe periods of depressed mood following stressful events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The energetics of gas flow and contact erosion during short circuit arcing

The processes governing the movement of short circuit arcs in circuit breakers are complex and variable and the detailed understanding of these processes is incomplete. This paper presents a new approach to our understanding of the short circuit arcing process by concentrating on the bulk thermal behavior and energetics of the arcing and gas flow during contact opening. It is shown how considerations of the arc power and the heating and vaporization of the contact material can be used to examine the flow of gas through the arc chamber and the erosion of contact material. Experimental data from a flexible test apparatus and arc imaging system along with measurements of pressure and arc current and voltage are used as the basis of the analysis. It is demonstrated how the air initially present in the arc chamber will be rapidly expelled from the arc chamber to leave an arc burning in the products of contact volatilization. Data on mass and volume flow rates are presented as well as estimates of the gas velocity in the contact region. These data provide information on the nature of the gas flow in the arc chamber as well as contact erosion during the arcing process. Arcing conditions of interest are short circuit faults (10/sup 3/-10/sup 4/ A) in low voltage (220-380 VAC) circuit breakers.     

VSAT maintenance and installation

Nationwide installation and maintenance of very-small-aperture terminals (VSATs) for satellite communication are explored. Installation methods are discussed, and the cost of installing a VSAT earth station is projected. Included in the discussion are the following issues: (1) how to overcome the local zoning and landlord objections; (2) how to get the material to the roof; (3) how to install the antenna without damaging the roof; (4) where to run the cable; and (5) how to do this when each site has its own installation environment and still hold the price of installation within reasonable bounds     

Interferometric fiber-optic sensing based on the modulation ofgroup delay and first order dispersion: application tostrain-temperature measurand

We describe an extension of low coherence interferometry which uses the complete interferogram rather than just the interferogram envelope. We measure the phase across the entire source spectrum using dispersive Fourier transform spectroscopy, and obtain group delay and dispersion from the phase curve. We apply the technique to a simultaneous quasi-static strain-temperature measurand in which strain and temperature are recovered from the modulation of group delay and first-order dispersion. We show these parameters have a negligible cross-term, yield a particularly robust transformation to strain and temperature, are immune to 2 π phase ambiguity and insensitive to fiber geometry. With an ultra broadband thermal source we achieved simultaneous resolution of strain acid temperature to accuracies of 5 μstrain.m and 0.35 K over strain and temperature ranges of 1200 μstrain.m and 22 K. We present detail of a diffraction grating-coupled multiple SELED source and its operation in optical fiber DFTS. With this source we achieved resolutions of <1 μstrain in single parameter measurement of strain and a temperature insensitive measurement of strain to within 15 μstrain.m over a strain range of 1200 μstrain.m in the presence of a temperature fluctuation of 20 K