42 research outputs found
Peatland Microbial Communities as Indicators of the Extreme Atmospheric Dust Deposition
We investigated a peat profile from the Izery
Mountains, located within the so-called Black Triangle,
the border area of Poland, Czech Republic, and Germany.
This peatland suffered from an extreme atmospheric
pollution during the last 50 years, which created an
exceptional natural experiment to examine the impact
of pollution on peatland microbes. Testate amoebae
(TA), Centropyxis aerophila and Phryganella
acropodia, were distinguished as a proxy of atmospheric
pollution caused by extensive brown coal combustion.
We recorded a decline of mixotrophic TA and
development of agglutinated taxa as a response for the
extreme concentration of Al (30 g kg−1) and Cu
(96 mg kg−1) as well as the extreme amount of fly ash
particles determined by scanning electron microscopy
(SEM) analysis, which were used by TA for shell construction.
Titanium (5.9 %), aluminum (4.7 %), and
chromium (4.2 %) significantly explained the highest
percentage of the variance in TA data. Elements such as
Al, Ti, Cr, Ni, and Cu were highly correlated (r>0.7,
p<0.01) with pseudostome position/body size ratio
and pseudostome position. Changes in the community
structure, functional diversity, and mechanisms of
shell construction were recognized as the indicators
of dust pollution. We strengthen the importance of the
TA as the bioindicators of the recent atmospheric
pollution
Energy-dispersive x-ray fluorescence spectrometer with capillary optics for the chemical analysis of atmospheric aerosols with high time resolution
Point source inoculation of Mesocyclops (Copepoda : Cyclopidae) gives widespread control of Ochlerotatus and Aedes (Diptera : Culicidae) immatures in service manholes and pits in North Queensland, Australia
This study details the novel application of predacious copepods, genus Mesocyclops, for control of Ochlerotatus tremulus (Theobald) group and Aedes aegypti (L.) mosquito larvae in subterranean habitats in north Queensland, Australia. During June 1997, 50 Mesocyclops sp. I were inoculated into one service manhole in South Townsville. Wet season rainfall and flooding in both 1998 and 2000 was responsible for the dispersal of copepods via the underground pipe system to 29 of 35 manholes over an area of 1.33 km(2). Significant reductions in Aedes and Ochlerotatus larvae ensued. In these habitats, Mesocyclops and Metacyclops were able to survive dry periods, when substrate moisture content ranged from 13.8 to 79.9%. At the semiarid inland towns of Hughenden and Richmond, cracking clay soil prevents drainage of water from shallow service pits where Oc. tremulus immatures numbered from 292-18,460 per pit. Introduction of Mesocyclops copepods into these sites during May 1999 resulted in 100% control of Oc. tremulus for 18 mo. One uninoculated pit subsequently became positive for Mesocyclops with resultant control of mosquito larvae
National progress in dengue vector control in Vietnam: survey for Mesocyclops (Copepoda), Micronecta (Corixidae), and fish as biological control agents.
X-ray Total Reflection Fluorescence Analysis of Iron, Copper, Zinc, and Bromine in Human Serum
Preconcentration of environmental trace elements on organic support for neutron activation and high resolution photon spectrometry
Migration of surface-associated microbial communities in spaceflight habitats
Astronauts are spending longer periods locked up in ships or stations for scientific and exploration spatial missions. The International Space Station (ISS) has been inhabited continuously for more than 20 years and the duration of space stays by crews could lengthen with the objectives of human presence on the moon and Mars. If the environment of these space habitats is designed for the comfort of astronauts, it is also conducive to other forms of life such as embarked microorganisms. The latter, most often associated with surfaces in the form of biofilm, have been implicated in significant degradation of the functionality of pieces of equipment in space habitats. The most recent research suggests that microgravity could increase the persistence, resistance and virulence of pathogenic microorganisms detected in these communities, endangering the health of astronauts and potentially jeopardizing long-duration manned missions. In this review, we describe the mechanisms and dynamics of installation and propagation of these microbial communities associated with surfaces (spatial migration), as well as long-term processes of adaptation and evolution in these extreme environments (phenotypic and genetic migration), with special reference to human health. We also discuss the means of control envisaged to allow a lasting cohabitation between these vibrant microscopic passengers and the astronauts