This paper presents a novel approach of measuring radon in-water in the field by inserting a MEDUSA gamma-ray detector into a 210 L or 1000 L container. The experimental measurements include investigating the effect of ambient background gamma-rays on in-field radon measurement, calibrating the detector efficiency using several amounts of KCl salt dissolved in tap water, and measuring radon in ...

The phenylpropenoids O-methyleugenol, O-methylisoeugenol and 2,3dimethoxycinnamaldehyde, have been isolated as the antimosquitocidal principles of the stem and root bark extracts of Uvariodendron pycnophyllum (Diels) R.E. Fr. The extracts and compounds exhibited activity with LC50 values in the range 17-59 ppm against the Anopheles gambiae s.s Giles mosquito larvae, while the constituent phenyl...

We have developed a procedure using solid-phase extraction (SPE) for the quantitative determination of oil films and slicks floating on water surfaces. During Phase One of this study, nine oil loadings (Exxon #6 fuel oil: 3 to 38 mg/cm) were sub sampled with C18-SPE disks in replicates (n = 2-4) from the surface of 1L beakers. Sonication and accelerated solvent extraction (ASE) were both tested...

The objective of this study was to establish the rate at which predatory leeches consume tubificid worms, at worm population densities simulating those of Cleveland Harbor. Two common species of leeches from Lake Erie were studied, Helobdella stagnalis and Erpobdella punctata. A mixed population of tubificids, mostly Limnodrilus hojfmeisteri, Limnodrilus cervix and Peloscolex multisetosus were ...

Introduction: The presence of ethane in liquidfilled lakes on Titan was confirmed by the Cassini Visible and Infrared Mapping Spectrometer (VIMS) in 2008, and has been investigated in further detail by the Cassini radar instrument [1,2]. Radar sounding, infrared absorption, and modeling suggest that the lakes are predominantly liquid methane and ethane, with trace amounts of propane, butane, ot...

Microfluidic systems provide new vistas for generation of droplets and bubbles with a perfect control over their volume and structure. The ability to form organic droplets in microdevices finds uses (and promises of uses) in a range of applications that divide into two general classes: (i) preparatory technique that utilize the droplets to form particles and capsules and (ii) analytical and syn...

Parasitological analysis of 5 sediment samples from latrine deposits spanning the time period from about 1880 to the 1930s are presented. Two sediment samples are from a latrine used by EuropeanAmericans. Three sediment samples are from latrines used by ChineseAmericans on the property of Wong Nim, an important member of the Chinese community. Two of the Chinese latrines were positive for human...

Gametic differentiation of the unicellular green alga Chiamydomonas reinhardtii proceeds in two steps controlled by the extrinsic signals nitrogen deficiency and light. Nitrogen deprivation induces the differentiation of vegetative cells to sexually immature pregametes. A light signal is required to convert the pregametes to gametes. Both signals are also required for the maintenance of mating ...

An unidentified mermithid species parasitizing Och/erotatus cantons is presented, being the first mosquito-parasitic mermithid recorded from Denmark. The parasitic development is initiated in the larval host, continues in the pupa and is completed in the abdominal haemocoel of the adult, the mean body length of the parasite increasing from about 1 mm to 12-13 mm. From 1 to 5 mermithid worms wer...