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Abstract Aedes aegypti is a major vector of Zika, dengue, and other arboviruses. Permethrin adulticidal spraying, which targets the voltage-gated sodium channel (VGSC), is commonly done to reduce local mosquito populations and protect humans from exposure to arbovirus pathogens transmitted by this dangerous pest. Permethrin resistance, however, is a growing problem and understanding its underlying molecular basis may identify avenues to combat it. We identified a single G:C polymorphism in pre-miR-33 that was genetically associated with permethrin resistance; resulting isoforms had structural differences that may affect DICER-1/pre-miRNA processing rates. We then assessed the effects of overexpression of pre-miR-33 isoforms on permethrin toxicological phenotypes, VGSC transcript abundance and protein levels for two genetically related mosquito strains. One strain had its naturally high permethrin resistance levels maintained by periodic treatment, and the other was released from selection. VGSC protein levels were lower in the permethrin resistant strain than in the related permethrin-susceptible strain. Overexpression of the G-pre-miR-33 isoform reduced VGSC expression levels in both strains. To further elucidate changes in gene expression associated with permethrin resistance, exome-capture gDNA deep sequencing, genetic association mapping and subsequent gene set enrichment analysis revealed that transport genes, in particular, were selected in resistant versus susceptible mosquitoes. Collectively, these data indicate that miR-33 regulates VGSC expression as part of a nuanced system of neuronal regulation that contributes to a network of heritable features determining permethrin resistance.

We describe the Sketch-and-Stitch method for bringing together a cognitive model and EEG to reconstruct the cognition of a subject. The method was tested in the context of a video game where the actions are highly interdependent and variable: simply changing whether a key was pressed or not for a 30th of a second can lead to a very different outcome. The Sketch level identifies the critical events in the game and the Stitch level fills in the detailed actions between these events. The critical events tend to produce robust EEG signals and the cognitive model provides probabilities of various transitions between critical events and the distribution of intervals between these events. This information can be combined in a hidden semi-Markov model that identifies the most probable sequence of critical events and when they happened. The Stitch level selects detailed actions from an extensive library of model games to produce these critical events. The decision about which sequence of actions to select from the library is made on the basis of how well they would produce weaker aspects of the EEG signal. The resulting approach can produce quite compelling replays of actual games from the EEG of a subject.

Open-ended tasks can be decomposed into the three levels of Newell's Cognitive Band: the Unit-Task level, the Operation level, and the Deliberate-Act level. We analyzed the video game Co-op Space Fortress at these levels, reporting both the match of a cognitive model to subject behavior and the use of electroencephalogram (EEG) to track subject cognition. The Unit Task level in this game involves coordinating with a partner to kill a fortress. At this highest level of the Cognitive Band, there is a good match between subject behavior and the model. The EEG signals were also strong enough to track when Unit Tasks succeeded or failed. The intermediate Operation level in this task involves legs of flight to achieve a kill. The EEG signals associated with these operations are much weaker than the signals associated with the Unit Tasks. Still, it was possible to reconstruct subject play with much better than chance success. There were significant differences in the leg behavior of subjects and models. Model behavior did not provide a good basis for interpreting a subject's behavior at this level. At the lowest Deliberate-Act level, we observed overlapping key actions, which the model did not display. Such overlapping key actions also frustrated efforts to identify EEG signals of motor actions. We conclude that the Unit-task level is the appropriate level both for understanding open-ended tasks and for using EEG to track the performance of open-ended tasks.

A large body of basic and applied research conducted at the UC Hopland Research and Extension Center (HREC) has focused on micro- or macroparasites that infest humans, domestic animals and wildlife, including viruses, bacteria, protozoans, helminths and blood-sucking arthropods. Approximately 17 microorganisms detected at the HREC are transmitted by ticks, and of these, at least five cause zoonotic diseases — animal-borne diseases that can be transmitted to people. Scientists working at the HREC identified the basic transmission cycle of the Lyme disease spirochete in the far-western United States. This information now is being used to develop and implement risk-assessment and preventive strategies.

During warm, sunny days (Max. temp. 22 °C to 25 °C) C02-baited traps operated at sites on and off snow patches (SP's) in subarctic Norway caught significantly fewer culicids, simuliids and tabanids on snow in both 1985 and 1987. However, for overnight catches (18.30 - 07.30 h) there was no significant difference in the number of culicids caught on versus off SP's. Analysis of videotapes taken in 1987 showed that defensive anti-fly behaviors of reindeer on and off SP's remained low (< 1/4 min) throughout the day. Based on reindeer anti-fly behaviors, harassment was greatest from 10.30 to 12.30 h (Norwegian Standard Time), but reindeer continued to aggregate on SP's while anti-fly behaviors were lowest (13.30 to 20.00 h). Groups of > 150 animals often occupied the entire surface of a snow patch. At the fly densities and climatic conditions encountered it seemed apparent that reindeer intermittently used SP's primarily to thermoregulate following periods of foraging. Almost all reindeer remained on SP's from 11.00 to 12.30 h, but at other times between 08.00 and 19 00 h about half the herd (ca. 800 animals) foraged for about an hour while the other half aggregated on SP's. However, by 20.00 h, during the cooler period when trap catches of mosquitoes were increasing, almost all reindeer had moved off SP's. The small decreases in anti-fly defensive behaviors observed for reindeer on SP's versus animals foraging in snow-free areas indicated that their presence on SP's may have resulted in a minor, coincidental reduction in harassment. Significantly more tabanids were caught during the morning trapping period than at other times, and significantly more mosquitoes were caught during the evening/overnight trapping period than at other times.

The reindeer nose bot fly Cephenemyia trompe aggregates on hilltops/mountaintops to mate. Although active only for brief periods on certain days, males have been collected only from such sites. To evaluate possible suppression of the fly population by killing males (by insecticides or traps) at such sites, the density of sites and the number of males at each site were monitored in a summer grazing area of the semidomestic reindeer host (Rangifer tarandus) in Finnmark, northern Norway. In an area of ca. 20 km2, 19 mating sites were detected and examined during 4 hours on one day. The number of males observed at most sites was 5-16 (range 3-60). Minor hilltops had few males but at some sites >20-60 flies were dispersed over an area of at least 100 m2. It is concluded that mating sites in the study area are too numerous, and also used by many beneficial non-target species, to be practical targets for control of the species.

Laboratory electrostimulated C. trompe (Modeer) females forcefully expelled (sprayed) larvae for 5-20 cm. The watery spray consisted of about 20 tiny droplets containing two to several larvae. Crawling first-instar larvae exhibited negative geotactic and phototropic responses; they were subject to rapid desiccation and became immobile as the tiny droplets dried within a few seconds. When 5-50 larvae from dissectedfemales were dropped in physiological saline onto different areas of the muzzle of restrained reindeer, only larvae placed deep within the nostrils and on the lips crawled out-of-sight down the nostril passage or into the mouth. Drops of larvae placed elsewhere quickly desiccated and the larvae became immobile. Larvae deposited by wild females onto a COz-baited reindeer model with the muzzle, lips and nostrils coated with insect trapping adhesive all were stuck only along the dorsal lip below the philtrum. All experimental evidence supports a natural per os mode of invasion.

Dette forskningsprosjektet på de økonomisk viktige artene for reindriften startet i 1983. Prosjektet er et internasjonalt samarbeid mellom forfatterne og med Økologisk Avdeling ved Universitetet i Tromsø under ledelse av professor Odd Halvorsen. Siktemålet med forskningen er å skaffe grunnleggende kunnskaper om disse to bremseartenes biologi, adferd, fysiologi og epidemiologi. Det ligger videre anvendte perspektiver, især når det gjelder mulighetene for biologisk kontroll, til grunn for prosjektet. Utviklingsfondet for reindrift og Universitetet i Tromsø har støttet prosjektet økonomisk. Feltarbeidet har i hovedsak foregått i Vest¬Finnmark.