Platinum Nanoparticle Decorated SiO 2 Microfibers as Catalysts for Micro Unmanned Underwater Vehicle Propulsion

Micro unmanned underwater vehicles (UUVs) need to house propulsion mechanisms that are small in size but sufficiently powerful to deliver on-demand acceleration for tight radius turns, burst-driven docking maneuvers, and low-speed course corrections. Recently, small-scale hydrogen peroxide (H2O2) propulsion mechanisms have shown great promise in delivering pulsatile thrust for such acceleration needs. However, the need for robust, high surface area nanocatalysts that can be manufactured on a large scale for integration into micro UUV reaction chambers is still needed. In this report a thermal/electrical insulator, silicon oxide (SiO2) microfibers, are used as a support for platinum nanoparticle (PtNP) catalysts. The mercapto-silanization of the SiO2 microfibers enables strong covalent attachment with PtNPs and the resultant PtNP-SiO2 fibers act as a robust, high surface area catalyst for H2O2 decomposition. The PtNP-SiO2 catalysts are fitted inside a micro UUV reaction chamber for vehicular propulsion; the catalysts can propel a micro UUV for 5.9 meters at a velocity of 1.18 m/s with 50 mL of 50% (w/w) H2O2.The concomitance of facile fabrication, economic and scalable processing, and high performance —including a reduction in H2O2 decomposition activation energy of 40-50% over conventional material catalysts—paves the way for using these nanostructured microfibers in modern, small-scale underwater vehicle propulsion systems

Alterations in biological properties of different lines of cytomegalorivus-transformed human embryo lung cells following in vitro cultivation.

Diverse alterations in biological properties of CMV-transformed cell lines were observed during prolonged in vitro cultivation. In the CMV-Mj-HEL-2 parent line there was a gradual decrease in the number of cells expressing CMV-related antigens; at the same time, an increase in oncogenicity was observed. One tumour line, designated CMV-Mj-HEL-2,T-1, however, retained the original ratio of cells expressing CMV-related antigens for over 100 in vitro passages. The cells lost their original moderate oncogenicity during this period. A later increase in the ratio of cells without CMV antigenic markers was accompanied by the return of moderate tumorigenicity and karyotypic changes. Both cell lines were studied to determine sensitivity to superinfection with herpesviruses, induction of immune response in nude mice, and release of infectious virus

Immune response of prostatic cancer patients to cytomegalovirus-infected and -transformed human cells.

The indirect immunofluorescent test was used to determine the prevalence of humoral immunity to cytomegalovirus (CMV)-induced antigens in prostatic cancer patients as compared to age-matched controls. Significantly more prostatic cancer patients demonstrated high CMV-antibody titers than did the benign prostatic hyperplasia and nonurogenital cancer groups; however, no significant difference in reactivity was found between paients with prostatic cancer and transitional cell carcinoma of the urinary bladder. When screened against CMV-transformed human cell lines, the reactivity of the sera followed the rate of expression of CMV-related antigens of cell lines used in these tests

Evidence for the association of cytomegalovirus with carcinoma of the prostate.

A human genital isolate of cytomegalovirus is shown to have transformed human embryonic lung cells in vitro. These cells produce tumors when injected into athymic nude mice. Two cell lines derived from tissue from human prostatic carcinoma have survived more than 20 passages in vitro and demonstrate cytomegalovirus-specific membrane antigen. Significant humoral antibody titers against cytomegalovirus have been demonstrated. Cell-mediated lymphocytotoxicity against these transformed cells has been demonstrated in patients with urinary tract tumors. This evidence indicates that an association between cytomegalovirus and human prostatic cancer may be more than coincidental