Isolation and Characterization of a New Bacterium from a Shallow Hydrothermal Vent in Tutum Bay, Papua New Guinea

An arsenic-rich shallow hydrothermal vent ecosystem in Tutum Bay, Papua New Guinea was the source of an enrichment culture for arsenate reducing microorganisms. From this enrichment culture a novel species of Burkholderia was isolated. It was analyzed by fatty acid methyl ester (FAME) and DNA-DNA hybridizations and tentatively named Burkholderia papuensis. This novel isolate is nicknamed strain April until there is valid publication of the species name. This strain is characterized as a gram-negative facultative aerobic bacterium able to reduce nitrate. It has a polar flagellum. Strain April has an optimum growth temperature between 30-37 0C and a temperature range from 40C to 400C. Its minimum pH is between 3-4, and its upper limit of growth is approaching pH 9.2. It can utilize glucose, benzoic acid, acetate, succinate, DL-malate, arabinose, and citrate. Strain April also has a tolerance to arsenate and arsenite up to at least 500 μM. The novel strain can reduce 2% of total arsenate when incubated in microoxic conditions. Strain April shows possible chemolithoautotrophic growth with O2 as the electron acceptor, and inorganic electron donors including thiosulfate. It does not seem to grow by chemolithoautotrophic means on H2S, sulfite, nitrite and arsenite

A magnetic bilateral tele-manipulation system using paramagnetic microparticles for micromanipulation of nonmagnetic objects

This study presents a scaled-bilateral telemanipulation system for magnetic-based control of paramagnetic microparticles. This bilateral control system consists of a haptic device (master-robot) and an electromagnetic system with four orthogonal electromagnetic coils. The electromagnetic system generates magnetic field gradients to control the motion of the microparticle (slave-microrobot). A systematic robust tele-manipulation control design of the microparticles is achieved using disturbance observers (DOBs) to estimate the interaction forces at both the master-robot and slave-microrobot. Experimental results show that point-To-point motion control of the slave-microrobots results in maximum position error of 8 μm in the steady-state. Furthermore, we demonstrate experimentally that interaction forces of tens of micro Newtons, between the slave-microrobot and non-magnetic microbeads, can be estimated using DOBs and scaled-up to the sensory range of the operator

Halophyte agriculture: success stories

The world's food production will need to increase by up to 70% by 2050 to match the predicted population growth. Achieving this goal will be challenging due to the decreased availability of arable land, resulting from urbanization and land degradation. Soil salinity is a major factor contributing to the latter process. While some improvement in crop yields in saline soils may be achieved as a consequence of single gene transfers, the real progress may be achieved only via a painfully slow “pyramiding” of essential physiological traits. Given the time constraints, a safer solution to meet the 2050 challenge may be to find alternative crop and forage species for farming in salt-affected conditions and to restore salt-affected areas. This review focuses on the suitability of halophytes to become important components of 21st century farming systems. We provide a comprehensive summary of the current use of halophytes for human food consumption, for forage and animal feeds, as oilseed and energy crops, and for desalination and phytoremediation purposes. We argue that the use of halophytes may be a viable commercial alternative to ease pressure on the requirement of good quality land and water for conventional cropping systems and the utilization of land degraded by salinity