Few studies have systematically addressed evolutionary changes in olfactory neuron assemblies, either by genetic drift or as an

adaptation to specific odor environments. We have studied the sense of olfaction in 2 congeneric scarab beetles, Pachnoda

interrupta Olivier and Pachnoda marginata Drury (Coleoptera: Scarabaeidae: Cetoniinae), which are both opportunistic

polyphages, feeding mainly on fruit and flowers. The 2 species occur in dissimilar habitats: P. interrupta is found in dry

savannah, and P. marginata in tropical parts of equatorial Africa. To study how these species may have adapted their sense of

olfaction to their odor environments, we utilized single-unit electrophysiology on olfactory sensilla with a wide selection of

food-related compounds. Despite the differences in habitat, we found that the species shared most of the physiological types

of olfactory receptor neurons (ORNs) encountered, although their proportions frequently varied between the species. The high

degree of conservation in olfaction between the species implies that a similar sensory strategy is efficient for food search in

both habitats. However, shifts in proportions of receptor neuron classes, and slight shifts in response profiles and/or presence

of some ORN classes unique to either species, may reflect adaptation to a different set of hosts.

Key words: comparative study, electrophysiology, olfaction, polyphagous herbivore, single sensillum recordings

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Few studies have addressed how olfactory systems may be adapted to different odour environments. I have performed the largest study to date, comparing olfactory receptor neurons in the two congeneric species of scarab beetle, P. marginata and P. interrupta. Both species are fruit- and flower-eaters but geographically separated (equatorial versus sub-Saharan Africa, resp.). They have similar lamellate antennae covered mostly with numerous olfactory sensilla placodea (plate sensilla) and a lesser number of other types, mainly sensilla coeloconica (grooved peg), and smooth peg sensilla of unknown function. By means of single sensillum recordings with tungsten microelectrodes I screened a great number of olfactory sensilla with a large array of odorants. I compared 456 sensilla placodea, containing 212 responding cells, over the whole antennae in both species. The olfactory systems of these two species displayed an amazing degree of conservation, with 20 identified olfactory neuron classes, all except two of which were found in both species with no detectable difference in response profiles. The exceptions were two olfactory receptor neuron classes: methyl benzoate and gamma-nonalactone, which were only found in Pachnoda marginata. In general, the two species showed an almost total overlap in their receptor neuron assemblies. One aim of the study was also to test whether the arrangement of neurons within sensilla was conserved between the species, but this could not be tested as very few combinations of characterized neurons were encountered during the study.

Key words: olfaction, electrophysiology, scarab beetles, Pachnoda marginata, Pachnoda interrupta, single sensillum recording, olfactory receptor neurons

Laser technologies have made distinguished contribution in modern industry. These have principally been realised through the important role played by lasers in advancement of manufacturing technology in areas such as welding. Laser welding has now become a very important joining technique in a wide variety of applications in the oil gas, aerospace, aircraft , medical and electronic industries.

This study presents investigations relating to the production of high quality laser welds that blend closely with surface of the welded materials, (welds termed 'net shaped'). It has not been possible to produce such welds in the past using conventional welding technology.Net shaped welds not only look attractive, but afford functional and economic benefit because no secondary machining and polishing is required.

Mild steel plates and bead-on-plate welding with a 1 kW fiber laser are usd for this investigation. Design of experiments and statistical modeling are used in the experimental study to understand parameter interactions. The independent process variables studied are power and welding speed. Experimental methods and results are detailed and results are discussed. The work shows that the laser and our work to date have made production of net shaped welds possible. The work could lead to new applications for very high geometry accuracy welding  

The sorghum chafer, Pachnoda interrupta Olivier

(Coleoptera: Scarabaeidae: Cetoniinae), is a key pest on

sorghum, Sorghum bicolor (L.) Moench (Poaceae), in

Ethiopia. At present there is a lack of efficient control

methods. Trapping shows promise for reduction of the pest

population, but would benefit from the development of

attractive lures. To find attractants that could be used for

control of P. interrupta, either by mass trapping or by

monitoring as part of integrated pest management, we

screened headspace collections of sorghum and the highly

attractive weed Abutilon figarianum Webb (Malvaceae) for

antennal activity using gas chromatograph-coupled electroantennographic

detection (GC-EAD). Compounds active in

GC-EAD were identified by combined gas chromatography

and mass spectrometry (GC-MS).

Information Communication Technologies (ICTs) provide an opportunity to meet the growing needs of rural areas. Many of the key features of ICT can be used to provide information and the requirements of people in rural areas. The digital divide considered is an important problem that countries face and it is much more complex than simply building out telecommunication networks and infrastructure. The divide is the result of a wide range of social factors, including but not limited to economy factors, education, literacy. Telecommunication infrastructure alone will not guarantee that users will be able to access and take advantage of services on the network. The paper begins with an introduction to the digital divide, and thus to highlight several successful initiatives provided by educational institutions and governmental organizations in Libya in the adoption of ICT. Finally, the paper provides some of the solutions proposed to reduce this divide.

ABSTRACT:Web-based forum is an application through the internet to facilitate the process of discussions and exchange of ideas. It is also referred to as online forums, message boards, discussion groups, and discussion forums. Youth can play a role in shaping their societies of immense diversity through the means of communication and participation, and sharing ideas. Therefore, this study leads to develop a web-based forum application to help young people express themselves and their needs, and desires. The requirements of the webbased application were identified from the students in UUM who are in the similar age group, design the application, and a prototype to implement the design. ---------------------------------------------------------------------

In this paper SiC particle reinforce aluminum metal matrix composite welded using high power continuous laser. Microstructure of laser beam welded SiC/Al MMC is characterized as functions of laser processing parameters. Results show that sound weld with little pores can be produced by laser beam welding, while aluminum carbide is formed in the weld. The size and the volume fraction of aluminum carbide are proportional to the laser power density. direction of shielding gas flow has significant effect on weld quality and weld microstructure.