Phenogenetic Analysis of Pygmy Wood Mouse (Apodemus uralensis Pall.) Populations in the Zone of the Eastern Ural Radioactive Trace (EURT)

Monitoring of A. uralensis populations in Kamenskii raion, Sverdlovsk oblast, in 1992–2002 and in Kaslinskii raion, Chelyabinsk oblast, in 2000–2001 revealed an increase in the proportion and diversity of minor morphogenetic aberrations and abnormalities in the structure of the cranium along the axis of the Eastern Ural Radioactive Trace (EURT). The samples from the southern and northern parts of the EURT (contaminated with ⁹⁰Sr to 500 and 4 Ci/km², respectively) were characterized by directed deviations from the control with respect to the frequencies of phenes of nonmetric cranial traits and an increase in the level of their fluctuating asymmetry in young females, which is indicative of epigenetic rearrangements in populations living in a radioactive environment.     

Health implications of the Tumaco earthquake, Colombia, 1979

A retrospective study of the effects of the Tumaco earthquake of 1979 shows a smaller number of deaths and injuries than in earthquakes of similar magnitude that have occurred elsewhere, which is probably related to the type of building. Most of the deaths were caused by a tsunami. Proportionally the mortality was higher in the 0 to 4 age group. Among the injured, most of the lesions were minor. Morbidity was higher in the over 45 years age group, and lower among the "under-fives." There was an evident need for a simple "disaster medical record card." Coordination among the different relief agencies could have been better.     

The influence of salinity on the rate of photosynthesis and abundance of some tropical phytoplankton

Several species of phytoplankton were grown in unialgal, but not bacteria-free, cultures. These clones when exposed to varying salinities, from 5 to 35, showed a marked increase in their rates of photosynthesis at low salinities. The optimum requirement of salinity, however, varied in different species. Observations on the relative abundance of phytoplankton in an estuary, where the salinity changes were fairly large, confirmed that, within limits, waters with low salinities support a greater abundance of phytoplankton in nature. The wide adaptability of phytoplankton to changes in salinity corresponds to the conditions brought about by the monsoon system along the southwest coast of India, where large dilutions are associated with the enrichment of water with nutrients.     

The fungal microcosm of the internodes of Spartina alterniflora

The internodal area of growing cord grass (Spartina alterniflora Loisel) is a microcosm colonized by the mycelium and heretofore unreported hyphopodial appendages of the fungus Sphaerulina pedicellata. As the plant matures and this area senesces during the late summer and fall, sexual stages of this and other fungi develop. Scanning electron micrographs revealed that this biomass supports bacterial growth and is grazed by nematodes and mites.     

Evaluation of California's graduated driver licensing program

Problem: California's graduated driver licensing (GDL) program was implemented to reduce the high crash risk of teenage drivers. The program enhancements made in 1998 were evaluated in this study using methods that rule out the noticeable downward trend in California teen's fatal/injury crash rates as a possible explanation for any observed crash reductions that could otherwise be mistaken for program effects. Method: Monthly per capita fatal/injury crash rates for 15-to-17-year-olds and proportional representations of 16–17-year-olds' nighttime and passenger crashes were analyzed using intervention time series analysis. Results: After removing trend, seasonality, and transition effects in the data, no overall reductions in fatal/injury crashes for 15–17-year-olds or 16-year-olds (separately) were found to be associated with the 1998 program enhancements, suggesting no overall exposure reduction effect of the longer instruction permit period nor increased competency associated with the higher number of required practice hours. However, the 12-month nighttime and 6-month passenger restrictions were found to be associated with annual savings of 55 and 816 fatal/injury crashes, respectively. Discussion: Finding no overall impact of the 1998 GDL enhancements was not surprising given findings of an earlier survey suggesting that California teens and parents were largely already practicing program requirements prior to implementation and were not fully complying with the program requirements afterwards. Though the observed crash savings associated with the restrictions were of modest size, this is the first study to evidence a direct positive impact of the passenger restriction component of GDL programs. Larger reductions could be realized if the nighttime restriction started earlier and parents/law enforcement could be motivated to better enforce these restrictions. Impact on Industry: The findings provide support for passenger and nighttime restriction components of GDL programs.     

Long-term behavior of passively aerated compost methanotrophic biofilter columns

The methane oxidation potential of several types of compost methanotrophic biofilter columns were compared in the laboratory over a period of 220 days. The results indicate an increase in methanotrophic activity over a period of about 100 days, up to a maximum of 400 g m(-2) day(-1), and a gradual decline to about 100 g m(-2) day(-1) within the next 120 days. High methane oxidation rates appear to be restricted to a small area of the column, 10-15 cm thick. Based on the laboratory investigations carried out to determine the cause for the decline in methane oxidation rate, it was concluded that the formation of exopolymeric substances (EPS), at the zones of maximum methane oxidation, was responsible for this decline. In monitoring methane oxidation in a column for up to 600 days, it was observed that mixing of the medium after formation of EPS enabled the column to temporarily recover high performance. The results suggest that stable, homogenous compost, with a low C/N and low ammonium content, mixed on a regular basis, could achieve and maintain high methane oxidation efficiencies.     

Current issues and uncertainties in the measurement and modelling of air-vegetation exchange and within-plant processing of POPs

Air-vegetation exchange of POPs is an important process controlling the entry of POPs into terrestrial food chains, and may also have a significant effect on the global movement of these compounds. Many factors affect the air-vegetation transfer including: the physicochemical properties of the compounds of interest; environmental factors such as temperature, wind speed, humidity and light conditions; and plant characteristics such as functional type, leaf surface area, cuticular structure, and leaf longevity. The purpose of this review is to quantify the effects these differences might have on air/plant exchange of POPs, and to point out the major gaps in the knowledge of this subject that require further research. Uptake mechanisms are complicated, with the role of each factor in controlling partitioning, fate and behaviour process still not fully understood. Consequently, current models of air-vegetation exchange do not incorporate variability in these factors, with the exception of temperature. These models instead rely on using average values for a number of environmental factors (e.g. plant lipid content, surface area), ignoring the large variations in these values. The available models suggest that boundary layer conductance is of key importance in the uptake of POPs, although large uncertainties in the cuticular pathway prevents confirmation of this with any degree of certainty, and experimental data seems to show plant-side resistance to be important. Models are usually based on the assumption that POP uptake occurs through the lipophilic cuticle which covers aerial surfaces of plants. However, some authors have recently attached greater importance to the stomatal route of entry into the leaf for gas phase compounds. There is a need for greater mechanistic understanding of air-plant exchange and the 'scaling' of factors affecting it. The review also suggests a number of key variables that researchers should measure in their experiments to allow comparisons to be made between studies in order to improve our understanding of what causes any differences in measured data between sites.     

Cloning and expression of high choriolytic enzyme,a component of the hatching enzyme system,during embryonic development of the marine ornamental fish<Emphasis Type="Italic"> Chrysiptera parasema</Emphasis>

In the present study, a cDNA for the hatching enzyme of a marine tropical fish, Chysiptera parasema, was cloned. This is the first demonstration of hatching enzyme cDNA from a marine tropical fish. The amino acid (aa) sequence deduced from the cDNA consisted of an 18-aa signal sequence, a 53-aa propeptide sequence and a 196-aa mature enzyme portion, having a consensus active site sequence for astacin family proteases. Phylogenetic analysis showed that the C. parasema enzyme was included in the clade of HCEs (high choriolytic enzymes), one of the hatching enzymes of freshwater fishes such as medaka (Oryzias latipes), masu salmon (Oncorhynchus masou) and zebrafish (Danio rerio), but not in the group of LCEs (low choriolytic enzymes), another type of hatching enzymes identified in the medaka. The developmental expression patterns of the C. parasema HCE gene were highly similar to that of the medaka HCE gene. The results suggested that the hatching enzyme system is highly conserved between these marine and freshwater fish species.Communicated by R. Cattaneo-Vietti, Genova     

Rotational application of bioinsecticide with deltamethrin-An antilarval measure for the control of filarial vector, Culex quinquefasciatus (Culicidae: Diptera)

A laboratory investigation was undertaken to study the cyclic usage of field recommended doses of Bacillus thuringiensis israelensis (Bti), Bacillus sphaericus (Bsp) and combination of Bti and Bsp (half the recommended dose of each) with deltamethrin 2.8 EC to attain better control of mosquito larvae. To understand the susceptibility status of the Culex quinquefasciatus larvae in the field, early fourth instar field collected larvae were exposed to the above treatments of biopesticides and were monitored for their persistency till 50% mortality was obtained. The larvae those survived in each treatment were transferred to the concentration of deltamethrin that gave 50% mortality. Observations on larval mortality after the treatment with deltamethrin were recorded after 24 h. The results revealed that Bti excels Bsp, as it recorded 54% mortality only on 17th day after application. The other salient finding of this study is LC50 of deltamethrin is sufficient to follow the biopesticides application for an effective control of Culex larvae.