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Adult female P. penetrans were incubated in 1, 5 and 10 ppm aldicarb for 1, 12 and 24 h at 7°C and processed for transmission electron microscopy either directly or following 36 h incubation in artificial tapwater (ATW). All treatments, except exposure to 1 ppm aldicarb for 1 h, induced increased densities of β-glycogen granules in non-contractile portions of muscle cells. 'Vacuoles', probably representing leached, saturated lipid droplets, were present in the cytoplasm of several cells after exposure to 5 ppm aldicarb for 24 h and 10 ppm for 12 and 24 h. At these concentrations and exposure times, internal dendrite terminals within the amphidial sheath cell processes hypertrophied. Two further effects observed in specimens treated with 10 ppm aldicarb for 24 h were the presence of large, electron-lucent granules in the amphidial sheath cell cytoplasm and denaturation of sarcoplasm of somatic muscle cells and anterior attachment processes of stylet protractor muscles. With the exception of β-glycogen granule densities, none of these effects was reversed by 36 h incubation in ATW. The significance of these findings and the mode of action of aldicarb at these concentrations are discussed in the light of earlier behavioural studies.

This paper describes two coupler method for measurement of dielectric properties of materials, at microwave frequencies. Two waveguide sections, fed from a common source, are coupling power into a waveguide filled with dielectric. The phase and attenuation constants are computed from the values of phase and attenuation adjustment required for cancellation of the signal in the dielectric filled waveguide. The two coupler method is particularly applicable for measurements of dielectric properties of aerosols and gases.

The ultrastructure of the cephalic sense organs of Hummerschmidtiella diesingi (Hammer-Schmidt, 1838), a parasite of cockroaches, is described using scanning and transmission electron microscopy. The four cephalic papillae are apparently mechanoreceptors and terminate as flattened dendritic processes within the cuticle. The hypodermis and sheath cells associated with these are described. The amphids resemble those described for other nematodes and are thought to be chemosensory. Each contains six main dendritic processes within the amphidial canal. Double and single microtubules, of varying arrangement, are present within these processes but basal bodies have not been found. The association between the amphids, the amphidial sheath cells and the hypodermis is also described. The inner and outer labial papillary neurons terminate beneath the cuticle and do not innervate cuticular sense organs. The outer labial dendrites, however, do produce dendritic processes. Possible functions of these sense organs are discussed.

This paper describes new insights into the behaviour and reliability of a long range subsea acoustic telemetry system. Field observations which may challenge the established theories for acoustic communication in shallow seas are discussed. The results of several years operation of such a system on a North Sea field are described and include reference to the suitability of various materials and designs for subsea connectors, cables and housings.

In the marine environment, commercial dispersants have been employed as part of the clean-up strategy following major oil spills since the late 1960’s and the Torrey Canyon disaster. However, considerable controversy has surrounded the use of these surfactant (“surface active agent”) formulations under such circumstances. Questions have been raised concerning their efficacy as counter-pollution measures and doubts have been expressed about the desirability of their large scale release into the environment. The innate toxicity of some of the early, hydrocarbon-based formulations and the synergistic effects that they produced with oils (see Blackman et al., 1977, 1978) spawned numerous field and laboratory studies. As a result, new, less toxic concentrated and water-miscible dispersant formulations were produced for marine use and most countries introduced rigorous guidelines to control their application.

This book provides a synthesis of the current understanding of the fate and effects of oil in freshwater. Its objectives are to provide a compilation, summary and critical evaluation of the available scientific literature on the impact of petroleum on freshwater organisms; to review procedures for the cleanup of petroleum from freshwater habits and to examine restoration and recovery rates; to provide background information on the chemistry and fate of petroleum in freshwater; and to identify gaps in the information on the effects of petroleum related contamination on freshwater. The book provides a source of data for the preparation of environmental impact statements predicting the effects of petroleum contaminated freshwater spills, and presents an introduction to methods of cleanup which are currently applied to the accidental release of petroleum.

Additional file 1: Maps showing IRS coverage in sub-Saharan Africa from 19972017 for carbamates, organochlorines, organophosphates and pyrethroids.

Additional file 3:Plasmodium falciparum infection prevalence from Bhatt et al. [1].

Additional file 1: Maps showing IRS coverage in sub-Saharan Africa from 19972017 for carbamates, organochlorines, organophosphates and pyrethroids.

Additional file 3:Plasmodium falciparum infection prevalence from Bhatt et al. [1].

Additional file 3:Plasmodium falciparum infection prevalence from Bhatt et al. [1].

Additional file 3:Plasmodium falciparum infection prevalence from Bhatt et al. [1].

Additional file 2: Maps showing modelled insecticide-treated bed net (ITN) coverage from Bhatt and Gething [35].

Additional file 2: Maps showing modelled insecticide-treated bed net (ITN) coverage from Bhatt and Gething [35].

Additional file 2: Maps showing modelled insecticide-treated bed net (ITN) coverage from Bhatt and Gething [35].

Additional file 1: Maps showing IRS coverage in sub-Saharan Africa from 19972017 for carbamates, organochlorines, organophosphates and pyrethroids.

Additional file 1: Maps showing IRS coverage in sub-Saharan Africa from 19972017 for carbamates, organochlorines, organophosphates and pyrethroids.

Identifications are suggested for 59 radio sources from the resurvey of declination zone �4�, 27 with galaxies and 32 with stellar objects; 19 of the latter are confirmed as quasi-stellar objects (QSOs). The identifications were made from the Palomar Sky Survey prints plus supplementary plates taken with the Palomar and U.K. Schmidt telescopes and the Anglo-Australian 3�9 m telescope.

Optical identifications are suggested for 122 weak radio sources from the Parkes 2700 MHz catalogue. Optical positions have been measured for the proposed counterparts and for 81 previously suggested identifications.