Chemical signaling between organisms is a ubiquitous and evolutionarily dynamic process that helps to ensure mate recognition, location of nutrients, avoidance of toxins, and social cooperation. Evolutionary changes in chemical communication systems progress through natural variation within the organism generating the signal as well as the responding individuals. A promising yet poorly understo...

Investigators often examine the factors—genetic or environmental—that determine the concentrations of secondary chemicals and growth, but few have examined both simultaneously. We used a factorial genetic design and manipulated nutrient availability to Salix sericea (Salicaceae) in order to quantify: (1) genetic variation, plasticity, and genetic variation in plasticity for growth rate and the ...

The main objective in the present study was to assess the spatial variation of chemical and physical soil properties and then use this information to select an appropriate area to install a pasture rehabilitation experiment in the Zereshkin region, Iran. A regular 250 m grid was used for collecting a total of 150 soil samples (from 985 georeferenced soil pits) at 0 to 30, and 30 to 60 cm layers...

Bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. High mixing that result in high heat and mass transfer rates are amongst their advantages. Heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reporte...

Leaf mass per area (LMA) is a morphological trait widely used as a good indicator of plant functioning (i.e. photosynthetic and respiratory rates, chemical composition, resistance to herbivory, etc.). The LMA can be broken down into the leaf density (LD) and leaf volume to area ratio (LVA or thickness), which in turn are determined by anatomical tissues and chemical composition. The aim of this...

Variation in the chemical composition of fish otoliths has been used in recent years to address a range of ecological questions, including levels of stock mixing, variation in habitat use, and rates of larval exchange. While some of these questions have been answered with varying success, the degree to which discrete populations are connected via larval exchange remains unknown. To identify lar...

MicroRNAs (miRNAs) are a class of small RNAs that typically function by guiding the cleavage of target messenger RNAs. They have been shown to play major roles in a variety of plant processes, including development, and responses to pathogens and environmental stresses. To identify new miRNAs and regulation in Arabidopsis (Arabidopsis thaliana), 27 small RNA libraries were constructed and seque...

douala metropolitan city loated in the littoral province of cameroon,has experienced a rapid urbaniation and industralisation. the city depends heavily on groundwater as a resource. due to ubiquitous sources of pollution, groundwater quality and contamination has become an imprtant issue for this urban groundwater supply. this study uses the major ion chemistry of groundwater together with t...

Our main objective in the present study was to assess the spatial variation of chemical and physical water properties. Prior to the design of groundwater quality monitoring networks, it is essential to investigate the spatial structure of the groundwater quality variables. A case study is presented which used ground water quality observations from groundwater domestic wells in the Dameghan, Ira...

1. The Executive Secretary is circulating herewith, for the information of participants in the seventh meeting of the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA), a background paper prepared by the International Plant Genetic Resources Institute (IPGRI) on on-farm management of crop genetic diversity. This information note supplements the progress report by the Ex...