Factors affecting buoyancy in the eggs of Bairdiella icistia (Pisces: Sciaenidae)

Several aspects of buoyancy were studied in the normally pelagic eggs of the sciaenid fish Bairdiella icistia (Jordan and Gilbert). Spawning fish acclimated to a low salinity (15‰) produced larger, more buoyant eggs which had a higher water content than eggs produced by fish living in ordinary sea water (33‰ S). Eggs fertilized in lower salinities were larger and more buoyant than eggs fertilized in higher salinities. The salinity of the medium during the first 5 to 7 min after fertilization had a lasting effect on egg buoyancy, but subsequent transfer to a different salinity also influenced buoyancy. Although egg buoyancy in this species can be influenced by the ambient salinity both before and after spawning, the capacity for adjusting buoyancy is limited, and eggs spawned in salinities lower than 30‰ would probably sink.     

Genetic Criteria for Establishing Evolutionarily Significant Units in Cryan's Buckmoth

Buckmoths ( Hemileuca spp.) are day-flying saturniid moths with diverse ecologies and host plants. Populations that feed on Menyanthes trifoliata , known commonly as Cryan's buckmoths, have been found in only a few bogs and fens near eastern Lake Ontario in New York and near Ottawa in Ontario, Canada. Because of their unique ecological traits, geographic isolation from other Hemileuca populations, and the small number of sites they occupy, there is concern that the Cryan's buckmoth populations are phylogenetically distinct and should be protected. The Cryan's buckmoths have not yet been taxonomically described and do not appear to have clear distinguishing morphological characters. Both molecular genetic traits (allozymes and mitochondrial DNA sequences) and an ecologically based character (host performance) were investigated to determine whether these populations possess fixed diagnostic characters signifying genetic differentiation from other eastern Hemileuca populations. Such differences would merit separate conservation management as an evolutionarily significant unit. Our studies showed that the Cryan's buckmoths clearly belong to the Hemileuca maia species group, but they could not be readily distinguished from other members of that group by means of molecular genetic techniques. There were no fixed differences in alleles or haplotypes distinguishing any of the populations or species, suggesting recent divergence. Nonetheless, in the host-plant performance experiment only the Cryan's buckmoth larvae were able to develop on M. trifoliata , a significant difference from other Hemileuca larvae tested. The Cryan's buckmoth appears to be unique in host performance and warrants protection and management us an evolutionarily significant unit. In cases such as this where groups appear to have recently diverged, investigations into ecologically significant traits may provide indicators of conservation significance as reliable as molecular genetic markers.     

Feeding,growth, and survival of Engraulis mordax larvae reared in the laboratory

Methods are described for the successful rearing of northern anchovy larvae (Engraulis mordax Girard) on cultured foods. Larvae were fed successively on the unarmored dinoflagellate Gymnodinium splendens, the veliger of the gastropod Bulla gouldiana, and nauplii of the brine shrimp Artemia salina. Rearing containers ranging in capacity from 4.5 to 510 l were tested; the smaller ones were found to be most useful for laboratory experimentation. Irreversible starvation occurred when E. mordax were denied food for more than 1.5 days after yolk absorption. Growth rates of larval anchovies fed different diets were compared. Larvae fed G. splendens grew for 1 week at the same rate as animals fed wild plankton, but did not maintain this rate. Laboratory survival of E. mordax larvae on a diet of G. splendens alone, did not differ significantly when veligers supplemented the diet. However, when G. splendens and veligers were fed simultaneously to E. mordax larvae, growth rate was greatly improved, although still not matching the growth attained on a diet of wild plankton. Length (L) versus weight (W) analyses were made for all larvae at all diets. The results showed that weight could be calculated most accurately from length by the relationship log W=3.3237 log L-3.8205, regardless of diet.     

Critical appraisal of available thermodynamic data for the complexation of antimony(III) and antimony(V) by low molecular mass organic ligands

Antimony is an element of increasing environmental significance but one whose chemical speciation has received little attention and, until recently, one which had not been modelled in any comprehensive way. This paper reports thermodynamic data for computer speciation models of antimony in aqueous, multicomponent solutions of environmental and biological interest involving low molecular mass organic ligands. The available data have been critically evaluated and entered into a thermodynamic database. The JESS suite of computer programs has been used to develop the thermodynamically-consistent mass balance equations used for modelling purposes. No data could be found for Sb(V) complexes and only a few of the existing data for Sb(III) complexes can be considered as being reliably described.     

Assessment of community noise problem in Greater Beirut Area,Lebanon

Over the last two decades, urban noise has been increasingrapidly, primarily in urban areas, due to population growthand the increase of certain noise sources. The main objectiveof this paper is to assess the sources and possible impactsof the community noise problems in Lebanese urban areas,particularly the Greater Beirut Area. The causes and effectsof community noise pollution are briefly presented. Soundpressure levels that were measured to define existing noiseexposure levels in various locations in the Greater BeirutArea are also presented. The attitudes toward noise pollutionand perceived annoyance impact on a sample of 1,038 exposedresidents are described. The association between measurednoise levels and sources, as well as annoyance, is examinedusing correlation analysis and linear and multiple linearregressions. A set of recommendations is presented to reducecommunity noise problem in Greater Beirut Area.     

Protective effects of thymoquinone and diallyl sulphide against malathion-induced toxicity in rats

Environmental Science and Pollution Research - Malathion is a potent organophosphate insecticide that inhibits acetylcholinesterase (AChE) enzyme. Our experimental objective was to investigate the...     

A behavior based safety approach at a Kuwait research institution

INTRODUCTION: Behavior based safety (BBS) initiatives are the current trend toward improving safety performance. METHOD: This study outlines the framework of the BBS process and summarizes several behavioral safety approaches to accident prevention. RESULTS: Although most of the published research has focused on the improvement of safe behavior in industry, this study is the first to apply the current approach of behavior based safety in a research/educational setting. An experiment conducted at a research institution demonstrated the effectiveness of a well-designed behavior based safety process. A follow-up study indicated that the BBS produced a lasting effect for the experimental group. IMPACT ON INDUSTRY: Results from this study can be the driving force to implement behavior-based safety processes into educational, research, and training organizations.     

Mitigation of CO<Subscript>2</Subscript> emissions from the road passenger transport sector in Bahrain

There is much optimism that the 2015 Conference of the Parties of the United Nations Framework Convention will yield an agreement on mitigation of climate change, to become effective in 2020. In this context, Bahrain represents a developing country with insufficient data to assess mitigation opportunities: its per capita carbon emissions rank among the world’s highest, yet there has been no research on the reduction potential of its rapidly growing transport sector. We examine this reduction potential and the costs of various mitigation measures and, further, explore barriers and the view of policymakers and experts. Potential benefits of combined mitigation scenarios are also identified based on their acceptability. We adopt a modified participatory method to develop the scenarios, using the long-range energy alternative planning (LEAP) modelling system, and find that an integrated policy approach can deliver a 23 % reduction in carbon dioxide emissions, costing 108 United States dollars per avoided metric tonne, with politically acceptable scenarios. Better performance, however, would require less acceptable approaches. These findings are significant for decision-making in Bahrain and other Gulf Cooperation Council countries; national target preparation and the setting of fuel economy standards should be begun promptly. We offer lessons to other developing countries on the timely regulation of technical specifications and numbers of passenger vehicles. Participatory approaches to the assessment of mitigation measures can advance environmentally effective, economically feasible and politically acceptable scenarios. The global community can use these results to provide necessary technical and financial assistance to developing countries.