26 research outputs found

    A Multi-Class SWAP-Test Classifier

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    Multi-class classification problems are fundamental in many varied domains in research and industry. To solve multi-class classification problems, heuristic strategies such as One-vs-One or One-vs-All can be employed. However, these strategies require the number of binary classification models developed to grow with the number of classes. Recent work in quantum machine learning has seen the development of multi-class quantum classifiers that circumvent this growth by learning a mapping between the data and a set of label states. This work presents the first multi-class SWAP-Test classifier inspired by its binary predecessor and the use of label states in recent work. With this classifier, the cost of developing multiple models is avoided. In contrast to previous work, the number of qubits required, the measurement strategy, and the topology of the circuits used is invariant to the number of classes. In addition, unlike other architectures for multi-class quantum classifiers, the state reconstruction of a single qubit yields sufficient information for multi-class classification tasks. Both analytical results and numerical simulations show that this classifier is not only effective when applied to diverse classification problems but also robust to certain conditions of noise.Comment: 13 pages, 9 figure

    Field Attractants for Pachnoda interrupta Selected by Means of GC-EAD and Single Sensillum Screening

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    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). Field trapping suggested that attraction is governed by a few influential compounds, rather than specific odor blends. Synthetic sorghum and abutilon odor blends were attractive, but neither blend outperformed the previously tested attractants eugenol and methyl salicylate, of which the latter also was part of the abutilon blend. The strong influence of single compounds led us to search for novel attractive compounds, and to investigate the role of individual olfactory receptor neurons (ORNs) in the perception of kairomones. We screened the response characteristics of ORNs to 82 putative kairomones in single sensillum recordings (SSR), and found a number of key ligand candidates for specific classes of ORNs. Out of these key ligand candidates, six previously untested compounds were selected for field trapping trials: anethole, benzaldehyde, racemic 2,3-butanediol, isoamyl alcohol, methyl benzoate and methyl octanoate. The compounds were selected on the basis that they activated different classes of ORNs, thus allowing us to test potential kairomones that activate large non-overlapping populations of the peripheral olfactory system, while avoiding redundant multiple activations of the same ORN type. Field trapping results revealed that racemic 2,3-butanediol is a powerful novel attractant for P. interrupta

    Ethnobotanical study of some of mosquito repellent plants in north-eastern Tanzania

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    The use of plant repellents against nuisance biting insects is common and its potential for malaria vector control requires evaluation in areas with different level of malaria endemicity. The essential oils of Ocimum suave and Ocimum kilimandscharicum were evaluated against malaria vectors in north-eastern Tanzania. An ethnobotanical study was conducted at Moshi in Kilimanjaro region north-eastern Tanzania, through interviews, to investigate the range of species of plants used as insect repellents. Also, bioassays were used to evaluate the protective potential of selected plants extracts against mosquitoes. The plant species mostly used as repellent at night are: fresh or smoke of the leaves of O. suave and O. kilimandscharicum (Lamiaceae), Azadirachta indica (Meliaceae), Eucalyptus globules (Myrtaceae) and Lantana camara (Verbenaceae). The most popular repellents were O. kilimandscharicum (OK) and O. suave (OS) used by 67% out of 120 households interviewed. Bioassay of essential oils of the two Ocimum plants was compared with citronella and DEET to study the repellence and feeding inhibition of untreated and treated arms of volunteers. Using filter papers impregnated with Ocimum extracts, knockdown effects and mortality was investigated on malaria mosquito Anopheles arabiensis and Anopheles gambiae, including a nuisance mosquito, Culex quinquefasciatus. High biting protection (83% to 91%) and feeding inhibition (71.2% to 92.5%) was observed against three species of mosquitoes. Likewise the extracts of Ocimum plants induced KD90 of longer time in mosquitoes than citronella, a standard botanical repellent. Mortality induced by standard dosage of 30 mg/m2 on filter papers, scored after 24 hours was 47.3% for OK and 57% for OS, compared with 67.7% for citronella. The use of whole plants and their products as insect repellents is common among village communities of north-eastern Tanzania and the results indicate that the use of O. suave and O. kilimandscharicum as a repellent would be beneficial in reducing vector biting. The widespread use of this approach has a potential to complement other control measures

    Prevalence of termites and level of damage on major field crops and rangelands in the Manasibu District, western Ethiopia

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    ABSTRACT: The current status of termite damage on maize (Zea mays(L.)), teff (Eragrostis tef (Zuccagni) Trotter), sorghum (Sorghum bicolor(L.)) and rangelands was studied in five Kebele administrations (study sites) and on three farmers' fields in every Kebele, in Manasibu District, Wellega Zone of Oromiya Regional State. Termite samples were collected from infested crop fields and rangelands, identified to the genus level with keys to the Ethiopian termites, and percentage occurrence for each genus was determined. Six genera of termites: Ancistrotermes, Macrotermes,Microtermes, Odontotermes, Pseudacanthotermes and Trinervitermes wereidentified. The first five genera belong to the subfamily Macrotermitinaewhereas Trinervitermes belongs to Nasutitermitinae. All of the generabelonged to the family Termitidae. Subterranean termites in general andMicrotermes in particular, were found to be the most prevalent termites in the study area. The damage that termites caused to maize and sorghum were assessed by the use of quadrates and that of teff by laying wooden frames in the quadrates. For all the three crops, damage was assessed at vegetative, flowering, and maturity stages. It was found out that the levels at which the three crops were damaged by termites were significantly different from each other. Teff was the most seriously damaged crop in the study area, followed by maize, while sorghum was the least affected crop. Damage at different stages, within each crop, were also found to be significantly variable from each other. To evaluate the impact of termites on rangelands in the absence and presence of grazing by livestock, three plots of rangelands were fenced and protected for six months. It was found that the protected plot of the rangelands significantly had higher percent vegetation cover and lower number of termite foraging holes per m2. From the study, it can be concluded that the genus Microtermes was the major termite species attacking crops and rangelands in Manasibu district, implying that most control strategies should focus on this genus, especially to control termites on teff and maize
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