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Notes: In recent Petawatt laser experiments at Lawrence Livermore National Laboratory, several hundred joules of 1 μm laser light in 0.5–5.0-ps pulses with intensities up to 3×1020 W cm−2 were incident on solid targets and produced a strongly relativistic interaction. The energy content, spectra, and angular patterns of the photon, electron, and ion radiations have all been diagnosed in a number of ways, including several novel (to laser physics) nuclear activation techniques. About 40%–50% of the laser energy is converted to broadly beamed hot electrons. Their beam centroid direction varies from shot to shot, but the resulting bremsstrahlung beam has a consistent width. Extraordinarily luminous ion beams (primarily protons) almost precisely normal to the rear of various targets are seen—up to 3×1013 protons with kTion∼several MeV representing ∼6% of the laser energy. Ion energies up to at least 55 MeV are observed. The ions appear to originate from the rear target surfaces. The edge of the ion beam is very sharp, and collimation increases with ion energy. At the highest energies, a narrow feature appears in the ion spectra, and the apparent size of the emitting spot is smaller than the full back surface area. Any ion emission from the front of the targets is much less than from the rear and is not sharply beamed. The hot electrons generate a Debye sheath with electrostatic fields of order MV per micron, which apparently accelerate the ions. © 2000 American Institute of Physics.

Notes: Abstract The sexual behavior of phytophagous insects is often integrated in a variety of ways with their host plants. This integration may be manifested as effects or influences of host plants on insect physiology and behavior, including sex pheromone communication, that reflect strategies by insects to optimize mating and reproduction. Certain insects sequester or otherwise acquire host plant compounds and use them as sex pheromones or sex pheromone precursors. Other insects produce or release sex pheromones in response to particular host plant cues. Chemicals from host plants often synergize or otherwise enhance insect responses to sex pheromones. By these means, host plants may be used by insects to regulate or mediate sexual communication. For many species of insects, host plant influences on insect sex pheromone communication may be important aspects of the formation of feeding and mating aggregations, of insect strategies to locate both hosts and mates, of behavioral reproductive isolation among sibling species, and of the regulation of reproduction to coincide with the availability of food and oviposition sites. Knowledge of these relationships is critical to understanding many different areas of the behavioral ecology of plant-feeding insects.

Notes: Background  Alcohol craving is a key element of the alcohol dependence syndrome. However, there is a lack of consensus about the precise nature of craving and the most appropriate method of measurement. Alcohol urges measured by the Alcohol Urge Questionnaire showed a unidimensional structure and evidence of validity and reliability in a US clinical population. The main aim of this study was to establish the validity of the AUQ in an untreated UK clinical population, and its relationships to drinking and personality factors.Subjects  All subjects (n = 80) were alcohol-dependent (DSM-IV) and presenting for pre-treatment assessment at a community alcohol team in South-west ­London.Method  All subjects completed the AUQ, Severity of Alcohol Dependence ­Questionnaire (SADQ), Spielberger's State Trait Anxiety Inventory (STAI) and Eysenck Personality Questionnaire (EPQ) and provided a breath specimen for alcohol analysis (BAL).Results  Principal components analysis of AUQ revealed one factor which accounted for 69% of variance with high interitem correlations, and an alpha reliability of 0.93. AUQ was significantly correlated with SADQ, BAC, state and trait anxiety and negatively correlated with time since last drink. There were no significant correlations between AUQ and any of the EPQ subscales. SADQ was correlated with neuroticism, but not other EPQ subscales. A regression analysis showed that only SADQ, time since last drink and BAL were significant predictors of alcohol urges.Conclusions  This study confirmed the AUQ factor structure and provided further evidence for the validity of AUQ. The relationship between BAL and urges deserves further research. The results did not support the contention that ­anxiety and personality factors predict urges when drinking-related variables, which also predict urges, are controlled for. The AUQ is a useful measure for clinical and experimental alcohol craving research.

Notes: Contributions of nursing research to nursing practice in the USA are increasing rapidly in four major areas: (1) the science of practice; (2) the artistry of practice; (3) the structures needed for optimal delivery of care; and (4) the methodologies needed for measurement and evaluation. Illustrative studies are described in each area, concluding with a plea for implementation of research findings. The authors presented this paper at the Open Forum, National League for Nursing Convention, 21 May 1975, New Orleans, Louisiana, USA, and it was first published in Journal of Nursing Administration (1976) March–April.

Notes: Abstract. The number of origins of pesticide resistance-associated mutations is important not only to our understanding of the evolution of resistance but also in modeling its spread. Previous studies of amplified esterase genes in a highly dispersive Culex mosquito have suggested that insecticide resistance-associated mutations (specifically a single-gene duplication event) can occur a single time and then spread throughout global populations. In order to provide data for resistance-associated point mutations, which are more typical of pesticide mechanisms as a whole, we studied the number of independent origins of cyclodiene insecticide resistance in the red flour beetle Tribolium castaneum. Target-site insensitivity to cyclodienes is conferred by single point mutations in the gene Resistance to dieldrin (Rdl), which codes for a subunit of a γ-aminobutyric acid (GABA) receptor. These point mutations are associated with replacements of alanine 302 which render the receptor insensitive to block by the insecticide. We collected 141 strains of Tribolium worldwide and screened them for resistance. Twenty-four strains contained resistant individuals. After homozygosing 23 of these resistance alleles we derived a nucleotide sequence phylogeny of the resistant strains from a 694-bp section of Rdl, encompassing exon 7 (which contains the resistance-associated mutation) and part of a flanking intron. The phylogeny also included six susceptible alleles chosen at random from a range of geographical locations. Resistance alleles fell into six clades and three clades contained both resistant and susceptible alleles. Although statistical analysis provided support at only the 5–6% level, the pattern of variation in resistance alleles is more readily explained by multiple independent origins of resistance than by spread of a single resistance-associated mutation. For example, two resistance alleles differed from two susceptible alleles only by the resistance-associated mutation itself, suggesting that they form the susceptible ancestors and that resistance arose independently in several susceptible backgrounds. This suggests that in Tribolium Rdl, de novo mutations for resistance have arisen independently in several populations. Identical alleles were found in geographically distant regions as well, also implying that some Rdl alleles have been exported in stored grain. These differences from the Culex study may stem both from differences in the population genetics of Tribolium versus that of mosquitoes and differences in mutation rates associated with point mutations versus gene duplication events. The Tribolium data therefore suggest that multiple origins of insecticide resistance (associated with specific point mutations) may be more common than the spread of single events. These findings have implications for the way in which we model the evolution and spread of insecticide resistance genes and also suggest that parallel adaptive substitutions may not be uncommon in phyletic evolution.