Although gamma ray showers are muon-poor, they still produce a number of muons suucient to make the sources observed by GeV and TeV telescopes observable also in muons. For sources with hard gamma ray spectra there is a relativèenhancement' of muons from gamma ray primaries as compared to that from nucleon primaries. All shower gamma rays above the photo-production threshold contribute to the n...

PURPOSE To describe a pilot study that evaluates the efficacy and mechanism of action of a new glaucoma operation, trabeculectomy with internal tube shunt. METHODS Twenty-three patients underwent the new operation in one eye for open angle glaucoma. Under a scleral flap, a deep sclerectomy was performed, resulting in an intrascleral lake. Laterally, on both sides, a small silicone tube was pl...

â  abastract â  the bed of the ancient lakes with having the fine granule sediments and fertile soil is a very good place for the extensive agricultural and industrial activities. the bed of ancient lake in khorramabad is a very good place for these activities. awaring of the exact limit and resolving of the morphometrical features of the same lake is very important, for environmental programmi...

Recently, there has been an increase in studies focusing on an emerging class of organic contaminants, hydroxylated PCBs (OH-PCBs) and chlorinated phenolic compounds (CPCs) in the environment, particularly in northern regions of Europe and Canada. Since information for fish from the Great Lakes are scarce, we determined the blood plasma concentrations of OH-PCB congeners, pentachlorophenol (PCP...

Total mercury levels in aquatic birds and fish communities have been monitored across the Canadian Great Lakes by Environment and Climate Change Canada (ECCC) for the past 42 years (1974-2015). These data (22 sites) were used to examine spatio-temporal variability of mercury levels in herring gull (Larus argentatus) eggs, lake trout (Salvelinus namaycush), walleye (Sander vitreus), and rainbow ...

Urban lakes performed several essential functions for the cities such as storing rainwater and providing recreation spaces. Blooms of cyanobacteria frequently occur in these lakes, disrupting water uses and decreasing ecosystem biodiversity. In order to study the impacts of watershed changes on cyanobacteria dynamics in urban lakes, a modelling approach in which an ecological lake model is conn...

Surface sediment cores from Oriole Lake (CA) were analyzed for organic carbon (OC), black carbon (BC), and their δ(13)C isotope ratios. Sediments displayed high OC (20-25%) and increasing BC concentrations from ∼0.40% (in 1800 C.E.) to ∼0.60% dry weight (in 2000 C.E.). Petrographic analysis confirmed the presence of fire-derived carbonaceous particles/BC at ∼2% of total OC. Natural fires were t...

Although gamma ray showers are muon-poor, they still produce a number of muons sufficient to make the sources observed by GeV and TeV telescopes observable also in muons. For sources with hard gamma ray spectra there is a relative ‘enhancement’ of muons from gamma ray primaries as compared to that from nucleon primaries. All shower gamma rays above the photoproduction threshold contribute to th...

The reproductive development of alligators from a contaminated and a control lake in central Florida was examined. Lake Apopka is adjacent to an EPA Superfund site, listed due to an extensive spill of dicofol and DDT or its metabolites. These compounds can act as estrogens. Contaminants in the lake also have been derived from extensive agricultural activities around the lake that continue today...

The level of Kluane Lake, the largest lake in Yukon Territory, was lower than at present during most of the Holocene. The lake rose rapidly in the late seventeenth century to a level 12 m above present, drowning forest and stranding driftwood on a conspicuous high-stand beach, remnants of which are preserved at the south end of the lake. Kluane Lake fell back to near its present level by the en...