607 research outputs found
Phosphate transport across the mitochondrial membrane: The influence of thiol oxidation and of Mg++ on inhibition by mercurials
Use of rice protein concentrate in rainbow trout feeding: preliminary results
During the past decades, the fishery industry has excessively used the world fish captures to produce fishmeal and fish oil in order to prepare feed for aquaculture diets. This has led to a drastic reduction of several fish populations (Hardy, 1999; FAO, 1999). At present 70% of the oil and 34% of fishmeal obtained from captures are used for aquaculture industry and, if the aquaculture production will continue to increase as predicted, in a short time it will absorb the entire world oil and fish meal production. Moreover, since fish meal still constitutes an important part of the feed formula for cultivated fish and since a further increase of fish meal availability will not be possible (Hardy, 2001), its price is expected to continue to increase (Tacon, 1998)
Live yeast (Saccharomyces cerevisiae var. boulardii) supplementation in fattening rabbit diet: Effect on productive performance and meat quality
The Radio Occultation experiment on-board the Indian OCEANSAT-2 mission: data processing validation and preliminary results
Ecopharmacology: Deliberated or casual dispersion of pharmaceutical principles, phytosanitary, personal health care and veterinary products in environment needs a multivariate analysis or expert systems for the control, the measure and the remediation
.The increasing human and animal use and abuse of drugs as well as of personalhealthcare and gross domestic products, involve disposal and waste problems and, as a consequence, affect the environmental condition. Actually most of the active principles are complex synthesised organic molecules that react, inside human or animal body, by specific biochemical reactions that in no case can reach a 100% yield and produce residues that could be more noxious of the starting compounds. Just reading the indication sheet accompanying any drugs, it is easy to state that no drug can be considered healthy, so, their use constitutes a serious pollution source. The full awareness of this relatively new environmental problem let many researchers to face it from different point of view. Current studies are considering the sources of these substances in the environment, the effects on human health as well as on the flora and fauna species, the recalcitrance and possible degradation methods, analytical techniques able to determine them and their metabolites even at low concentrations and in complex matrices. Literature on the subject continuously increases and a comparison of all data became more and more difficult both for a single drug and for different ones based on the same or different active principles. This is a typical case in which chemometrics can extract a full information in the easier way, so the design of a European database coupled to suitable expertsystem software should be strongly suggested
Estimate of a spatially variable reservoir compressibility by assimilation of ground surface displacement data
Abstract.
Fluid extraction from producing hydrocarbon reservoirs can cause anthropogenic land subsidence. In
this work, a 3-D finite-element (FE) geomechanical model is used to predict the land surface displacements above
a gas field where displacement observations are available. An ensemble-based data assimilation (DA) algorithm
is implemented that incorporates these observations into the response of the FE geomechanical model, thus re-
ducing the uncertainty on the geomechanical parameters of the sedimentary basin embedding the reservoir. The
calibration focuses on the uniaxial vertical compressibility
c
M
, which is often the geomechanical parameter to
which the model response is most sensitive. The partition of the reservoir into blocks delimited by faults moti-
vates the assumption of a heterogeneous spatial distribution of
c
M
within the reservoir. A preliminary synthetic
test case is here used to evaluate the effectiveness of the DA algorithm in reducing the parameter uncertainty
associated with a heterogeneous
c
M
distribution. A significant improvement in matching the observed data is
obtained with respect to the case in which a homogeneous
c
M
is hypothesized. These preliminary results are
quite encouraging and call for the application of the procedure to real gas fields
Influence of the assessment of defect severity and intravenous nitrate administration during tracer injection on the detection of viable hibernating myocardium with data-based quantitative technetium 99m-labeled sestamibi single-photon emission computed tomography.
Heterozygous, Polyploid, Giant Bacterium, Achromatium, Possesses an Identical Functional Inventory Worldwide across Drastically Different Ecosystems
Achromatium is large, hyperpolyploid and the only known heterozygous bacterium. Single cells contain approximately 300 different chromosomes with allelic diversity far exceeding that typically harbored by single bacteria genera. Surveying all publicly available sediment sequence archives, we show that Achromatium is common worldwide, spanning temperature, salinity, pH, and depth ranges normally resulting in bacterial speciation. Although saline and freshwater Achromatium spp. appear phylogenetically separated, the genus Achromatium contains a globally identical, complete functional inventory regardless of habitat. Achromatium spp. cells from differing ecosystems (e.g., from freshwater to saline) are, unexpectedly, equally functionally equipped but differ in gene expression patterns by transcribing only relevant genes. We suggest that environmental adaptation occurs by increasing the copy number of relevant genes across the cell’s hundreds of chromosomes, without losing irrelevant ones, thus maintaining the ability to survive in any ecosystem type. The functional versatility of Achromatium and its genomic features reveal alternative genetic and evolutionary mechanisms, expanding our understanding of the role and evolution of polyploidy in bacteria while challenging the bacterial species concept and drivers of bacterial speciation
Nutritional value of two insect larval meals (Tenebrio molitor and Hermetia illucens) for broiler chickens: Apparent nutrient digestibility, apparent ileal amino acid digestibility and apparent metabolizable energy
- …