Water Quality Simulation for Planning Restoration of a Mined Watershed

Water quality simulation was performed to evaluate the effects of restoration alternatives on metals transport in a mountainous watershed in Montana, U.S.A. impacted by hundreds of abandoned hardrock mines. The Water Quality Analysis Simulation Program (WASP5), developed by the U.S. Environmental Protection Agency (U.S. EPA), was used to assist in planning restoration of the Upper Tenmile Creek watershed, a major drinking water supply for the City of Helena. Synoptic survey data collected by U.S. EPA and the U.S. Geological Survey were used for model calibration and validation. The effectiveness of eight restoration alternatives was modeled under steady-state, low flow conditions. These alternatives ranged from removal of adit and point source discharges to modification of the water supply scheme to provide higher in-stream flows. The model was also used for a number of related purposes, including evaluation of metals loadings and losses, exceedances of water quality standards, interactions between metals in water and bed sediment, and model and data uncertainties. Although standards exceedances are common throughout the watershed, modeling results indicated that removal of point sources, mine waste near watercourses, and streambed sediment can help improve water quality. Alteration of the water supply scheme and increasing baseflow will also ultimately be required to meet standards for all metals. The model also showed that although adits and point sources contribute significant metals loadings to the stream during baseflow, in some areas shallow groundwater and bed sediment can also be sources of metals. Adsorption and precipitation onto bed sediments are also important loss mechanisms in some locations. The model helped to identify uncertainties in the metal partition coefficients associated with sediment, significance of precipitation reactions, and locations of unidentified sources and losses of metals.     

Biomimetic transport of simple olive biophenol and analogues through model biological membranes by differential scanning calorimetry.

The different interactions of p-hydroxybenzoic acid (1), a simple biophenol (BP) found in olives and their food products, and its substitute analogues, benzoic (2), anisic (3), and toluic (4) acids, with a model membrane represented by dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLV) was studied by differential scanning calorimetry (DSC). The influence of their different lipophilic character on transfer and absorption processes through an aqueous medium into a lipid bilayer was also investigated. DSC experiments allowed monitoring of the interaction of BP with biomembranes by considering the effects exerted on the thermotropic behavior of DMPC multilamellar and unilamellar vesicles at different pHs (4 and 7.4). The examined compounds affect the transition temperature (T(m)) of phospholipid vesicles, causing a shift toward lower values, which is modulated by the molecular fraction entering into the lipid bilayer, as well as by their molecular interaction with the lipids. Kinetic calorimetric measurements were performed on suspensions of blank liposomes immediately after being added to fixed weighed amounts of powdered compounds and after increasing incubation periods at 37 degrees C. T(m) shifts, due to molecular dissolution and transfer of the compounds into the membrane surface occurring during the incubation time, were compared with those determined by a fixed molar fraction of free compounds directly dispersed in the membrane. The results show that the kinetic process, involved in molecular release, transfer through aqueous medium, and uptake by the model membrane surface, is influenced by lipophilicity as well as by pH, acting on the acid solubility and membrane disorder, allowing us to gather useful information on the BP intake process of olive derived foodstuffs.     

Distribution of Heavy Metals in Marine Sediments of Palermo Gulf (Sicily, Italy)

Concentrations of Cr, Cu, Hg, Pb and Zn have been measured, by atomic absorption spectrophotometry, in the fine fraction (<63 μm) of surface sediments collected in 30 sites in the Palermo Gulf (Sicily, Italy) in order to assess the levels and the spatial distribution of these elements. Enrichment factors calculated with respect to clean areas have been considered to discriminate between levels due to background or to pollution contributions. The sampling stations, which form a grid inside these areas, are characterized by geographic proximity and by the presence of pollution sources. Ratio matching technique along with hierarchical clustering, minimum spanning tree and principal component analysis have been used for the statistical analysis of data, allowing to better describe the spatial distribution of metal levels. Our work allowed to assess the anthropogenic contribution to the pollution of the area under investigation through industrial and domestic wastes, presence of an harbour area and river inflow.     

Mortality outbreak by perch rhabdovirus in European perch (Perca fluviatilis) farmed in Italy: Clinical presentation and phylogenetic analysis

This work reports a mortality outbreak, occurred in 2015 and affecting juveniles of European perch (Perca fluviatilis L.) farmed in Italy. Perch rhabdovirus (PRV) was detected by viral isolation and biomolecular investigations. Phylogenetic analysis clustered our isolate into genogroup B, which also includes PRV isolates from Perca fluviatilis identified in France (2004–2009); diagnostic investigations also revealed opportunistic bacteria (Aeromonas hydrophila) and parasites (Chilodonella piscicola). Since, occasionally, PRV has been reported in the natural environment, which is often a source of eggs and broodstock for farms, it could be possible that both similar France and Italian isolate were imported from a same place elsewhere and have a common origin. Improving biosecurity measures (batch control) and disinfection of egg strings with an iodine‐based solution helps prevent apparent vertical transmission of PRV.     

Inflorescence bud growth,development and abscission in shoots of bearing and disbudded ‘Bianca’ pistachio trees

Summary

Dry-matter accumulation patterns and anatomical aspects of development and abscission of inflorescence buds borne on shoots of fruiting (BF) and non-fruiting (BNF) branches of bearing trees and in non-bearing branches of disbudded (NBD) pistillate trees of pistachio (Pistacia vera L.) were studied from the end of May to mid September. In NBD trees, inflorescence-bud summer drop was negligible and, by the end of the growing season, dry-matter content in NBD buds was three times higher than in BF buds. The anatomical investigation showed that the inflorescence buds, irrespective of their being on shoots of fruiting or not-fruiting branches, undergo the same differentiation process, which is completed by the end of spring. In June and July, signs of degenerations are detectable in the conducting tissue of the buds that will abscise. The degeneration seems to precede and, presumably, trigger the onset of abscission layers, which may develop in different points of the inflorescence. It is suggested that the event triggering the onset of the abscission process precedes the phase of rapid embryo development and that it might be ascribed to the embryo in the phase following the first zygotic division.     

Long-term evaluation of yield components of young olive trees during the onset of fruit production under different irrigation regimes

A four-year study was conducted on young Olea europaea L. trees to investigate the effect of deficit irrigation starting from the onset of fruit production. Subsurface drip irrigation was used to supply 100% (FI), 46–52% (DI), or 2–6% (SI) of tree water needs. Tree growth was reduced by deficit irrigation, whereas, return bloom was not. Per tree fruit yield of DI trees was 68% that of FI, but fruit yield efficiency based on tree size was similar between treatments. Fruit set and the number of fruits of FI trees were similar to those of DI trees and significantly higher than in SI trees. No significant differences in fruit fresh weight were found between FI and DI. The oil yield and oil yield efficiency of the DI treatment were 82 and 110% that of FI trees, respectively. A level of about 50% deficit proved sustainable to irrigate trees for oil production.     

Treatment of a poorly differentiated sarcoma in the oropharynx of a horse

A 10-year-old Thoroughbred mare was referred to Tennessee Equine Hospital for evaluation and treatment of a subepiglottic mass. Physical and laboratory examinations revealed no other abnormalities. The tumour was excised through a laryngotomy site using transendoscopic laser and sharp excision. Histological evaluation revealed a poorly differentiated sarcoma with features of a leiomyosarcoma, a rarely identified neoplasm in the oropharynx of the horse. The mare developed intermittent dorsal displacement of the soft palate (iDDSP) after surgery but was able to resume full training. There was no evidence of regrowth 8 months post-operatively.