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Publisher Summary This chapter focuses on gustation (taste) and olfaction (smell). Both olfactory and gustatory sensory cells are primary neurons; that is, they connect the periphery (sensillum) directly with the central nervous system. Olfactory cells, on the antennae as well as on the palpi, send their axons directly to the antennal lobe, which is a part of the insect brain. Gustatory cells, for the most part, send their axons to the ganglion for the segment in which the sensory cell occurs. For the creature to taste or smell anything, there must be a pathway from the outside to the sensory cells inside. On various parts of the insect body, but particularly on the antennae, mouthparts, legs, and ovipositor (egg-laying structure), insects possess a variety of cuticular elaborations in which are housed chemically sensitive cells. These cuticular structures take the form of hairs (trichoids), pegs, pegs in pits, flat surfaces, and several other shapes. Common to all of them is a modified cuticular region that will provide one or more pores through which chemicals can gain entry. Chemicals enter gustatory sensilla via the single pore in the tip. This pore contains a sugar–protein complex (mucopolysaccharide) that protects the dendrites from desiccation and probably limits the types of chemicals that can pass. Once past this barrier, the chemical enters the solution around the dendrites and potentially can interact with the cell.

A structured approach to testing software based on the principles of the McCabe cyclomatic complexity metric is described. This approach is being applied to current Naval embedded weapon system software projects for unit, integration, and computer software configuration item (CSCI) requirements-level testing. The primary automated tool supporting this process is the Vitro Automated Structured Testing Tool (VASTT), which analyzes and generates reports from a variety of inputs, including data flow diagrams (DFDs), program design language (PDL), and several programming languages. The reports include complexity metrics, flow graphs, test paths, and test cases. This approach to testing provides an early assessment of testability and a comprehensive and quantifiable framework for the testing program. >

This paper will describe a 30-GHz monolithic low-noise balanced mixer which has been developed using an integrated bow-tie antenna to waveguide transition and low parasitic Mott diodes. The diodes and mixer circuit were developed using MBE material and were fabricated using a plated airbridge technology. Measurements on the diode at dc and RF showed that the zero bias junction capacitance was 0.025 pF and the series resistance was 10 Omega. A mixer conversion loss of 6 dB was measured at 30 GHz with an IF of 1 GHz.

Electrophysiological investigations show that chemosensitive cells in tarsal setae of the spruce budworm are sensitive to at least two salts and possibly water. Two cells are involved in the salt response and one in the possible water response. Each seta also has a cell which responds to mechanical deformation. Stimulation with four sugars did not show that a specific sugar sensitive cell is present in these setae. Results are compared with those from other arthropods.

This paper reviews studies on adult Chrysomelid beetles which have provided insight into the role of phytochemicals as feeding attractants, stimulants, deterrents and host-recognition factors in general. Available evidence is discussed in the following major contexts: (1) attractants and distance recognition of host plants; (2) close range host-plant recognition; (3) concepts and mechanisms of feeding deterrents. Behavioural and sensory physiological data are emphasized, and the extent to which these can be correlated are discussed. Comparisons among closely related species are made whenever possible in order to explore the subtle differences in chemosensitivity which may underlie major differences in host-plant relationships which are known to exist. Six genera have received the greatest attention in the literature and data on them are discussed in some detail. These genera are Leptinotarsa, Chrysolina, Entomoscelis, Diabrotica, Galerucella, Phyllotreta. It is clear from the data available that the chemical and the chemosensory basis of host-plant recognition, in general, is complex. Details underlying recognition and non-recognition will be pursued most fruitfully using a few model species for which we have a reasonable amount of basic sensory information. Chrysomelid beetles provide excellent models for future studies in this field.

The peripheral distribution of the mesothoracic nerves of the adult male Choristoneura fumiferana (Clem.) is described in detail. The peripheral nerves are grouped into major root systems, termed here, the dorsal root, anterior root, posterior root and leg root. These nerve roots are described for C. fumiferana and compared with the mesothoracic nerve patterns of 5 insect orders: Orthoptera, Dictyoptera, Plecoptera, Neuroptera and other Lepidoptera. Tables listing the homologous mesothoracic muscles in the above 5 orders are presented.

Electrophysiological studies show that at least six sensilla on the various mouthparts of larval Colorado potato beetles (Leptinotarsa decemlineata) contain chemosensory cells. These sensilla are found on the galea, maxillary palps, and labial palps. Sodium chloride, sucrose, some amino acids, and chlorogenic acid are among the effective stimuli. The sensitivity spectrum of these cells correlates with known larval phagostimulants.