Cooling of freshly formed Cheddar
cheese is thought to be one of the processing
steps that requires tighter control
to achieve more uniform and consistent
product quality. Cheese samples, obtained
after pressing, were rapidly cooled
to 5, 15, 25, or 35°C. Commercial samples
and test cheese at 7, 30, 60,...
Grazing by phagotrophic flagellates and ciliates is a major source of mortality for bacterioplankton in both
marine and freshwater systems. Recent studies have demonstrated a positive relationship between clearance
rate and prey size for bacterivorous protists. We tested the idea that, by selectively grazing the larger (more
actively growing or...
We propose quantification of the activity of digestive enzymes as a novel way to estimate
rates of protist grazing in natural waters. Our first application of this approach was determination of
protistan bacterivory by assaying the activity of lysozyme at acid pH. Lysozyme specifically degrades
peptidoglycan, a major structural component...
Previous work has demonstrated selective feeding by bacterivorous protists on the of prey size. Other prey characteristics may also affect protist grazing rates. In this relative uptake rates of fluorescently labeled bacterial (FLB) cells made from starving bacteria (S-FLB), and of live-stained motile vs non-motile bacteria by marine We also...
We evaluated the extent to which the average metabolic activity of open ocean bacterioplankton
changed during 2 to 3 d incubations of 1 μm filtered seawater at in situ temperature. Indices
of bacterial activity during incubation experiments were compared to those of in situ bacterioplankton,
which were repeatedly sampled at...
Three staining methods were used to identify metabolically active bacteria in Lake Kinneret, northern Israel: CTC, DAPI staining followed by a propanol wash, and the Molecular Probes Live/Dead stain. Positive results from these methods purport to show, respectively, actively respiring bacteria (CTC+), cells with intact nucleoids (NuCC), and cells with...
Until recently, studies of the fate of primary production in coastal upwelling systems have focused mainly on export through sinking of particulate organic matter (POM). In week-long deck incubations conducted during the upwelling season off Oregon, a large accumulation of carbonrich (C:N ≥ 16) dissolved organic matter (DOM) occurred following...
Increasing international trade and tourism have led to an increase in the introduction of exotic pests that pose a considerable economic threat to the agro-ecosystems of importing countries. Scale insects (Sternorryncha: Coccoidea) may be contaminants of export consignments from the South African deciduous fruit industry to the European Union, Israel,...
Multiplicative random cascades (MRCs) can parsimoniously generate highly intermittent patterns similar to those in rainfall. The elemental MRC model parameter is the cascade weight, which determines how rainfall at one scale is partitioned at the next smallest scale in the cascade. While it is known that the probability density of...