The effect of vibration frequency and amplitude on biofouling deterrence.

The use of vibration is proposed as a means of controlling the settlement of marine fouling organisms. In this study, panels with embedded lead zirconate titanate, known as PZT, were placed in the field over 3 months. The panels were vibrated at different velocity levels at frequencies between 70 and 445 Hz. It was found that barnacles (Amphibalanus variegatus Darwin and Elminius sp.) were the only fouling organisms affected by the applied vibration, and these organisms settled in significantly lower numbers when the plates were excited at specific frequencies and amplitudes. Panels vibrating at relatively higher frequencies, greater than 260 Hz, exhibited reduced barnacle settlement, whilst lower frequencies in the 70-100 Hz range had little or no effect. The settlement of other fouling organisms such as tubeworms, bryozoans, ascidians and algae did not appear to be affected by the applied excitation. The experimental results showed that increasing the velocity amplitude of vibration was a contributing factor in inhibiting barnacle settlement.

Human rights and mass disaster: lessons from the 2004 tsunami.

This paper describes the results of an investigation into how the December, 2004 tsunami and its aftermath affected the human rights of the survivors. Teams of researchers interviewed survivors, government officials, representatives of international and local nongovernmental organisations, UN officials, the military, police, and other key informants in India, Sri Lanka, the Maldives, Indonesia, and Thailand. We also analysed newspaper articles, reports released by governments, UN agencies, NGOs, and private humanitarian aid groups, and we examined the laws and policies related to survivors' welfare in the affected countries. We found worsening of prior human rights violations, inequities in aid distribution, lack of accountability and impunity, poor coordination of aid, lack of community participation in reconstruction, including coastal redevelopment. Corruption and preexisting conflict negatively impact humanitarian interventions. We make recommendations to international agencies, states, and local health service providers. A human rights framework offers significant protection to survivors and should play a critical role in disaster response.

General purpose, field-portable cell-based biosensor platform.

There are several groups of researchers developing cell-based biosensors for chemical and biological warfare agents based on electrophysiologic monitoring of cells. In order to transition such sensors from the laboratory to the field, a general-purpose hardware and software platform is required. This paper describes the design, implementation, and field-testing of such a system, consisting of cell-transport and data acquisition instruments. The cell-transport module is a self-contained, battery-powered instrument that allows various types of cell-based modules to be maintained at a preset temperature and ambient CO(2) level while in transit or in the field. The data acquisition module provides 32 channels of action potential amplification, filtering, and real-time data streaming to a laptop computer. At present, detailed analysis of the data acquired is carried out off-line, but sufficient computing power is available in the data acquisition module to enable the most useful algorithms to eventually be run real-time in the field. Both modules have sufficient internal power to permit realistic field-testing, such as the example presented in this paper.