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

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

Zawartość amin biogennych w serze pleśniowym w trakcie przechowywania

The aim of this research was to study the formation of seven biogenic amines (histamine, agmatinc, spermine, spermidine, cadaverine, putrescine and tyramine) in three commercial mould cheeses from three different producers from the area of the Central Europę during 8-week storage in refrigerator at 6 š 2 °C. The analysis of biogenic amines was madr every week during 8-week of storage. Biogenic amines were extracted from the mould cheese by diluted HCl and determined using ion-exchange chromatography with post-column ninhydrin detection. Spermidine, spermine, putrescine and cadaverine were detected in tested mould cheeses. Spermidinc was quantitatively the most important biogenic arnuie in all samples. While spermidine was detected immediately after purchase of samples, the rest of detected biogenic amines were developed during storage. The amount of putrescine was mostly increased during storage while the concentration of spermidine was decreased during storage. However, after 8 weeks of storage all samples contained toxicologically insignificant concentrations of detected biogenic amines in comparison with EU legislation and scientific literature and can be considered to be safe for human health.Celem pracy było zbadanie syntezy siedmiu amin biogennych (histaminy, agmatyny, sperminy, spermidyny, kadaweryny, putrescyny i tyraminy) w trzech komercyjnie dostępnych serach pleśniowych pochodzących od różnych producentów z Europy Środkowej w czasie 8-tygodniowego przechowywania w lodówce w temperaturze 6 š 2°C. Oznaczenia poziomu amin biogennych wykonywano raz w tygodniu. Aminy biogenne były izolowane z sera pleśniowego przez rozcieńczony HC1 i oznaczane metodą chromatografii jonowymiennej i postkolumnowej reakcji ninhydrynowej. W badanych serach wykryto obecność spermidyny, sperminy, putrescyny i kadaweryny. W największych ilościach występowała spermidyna. Związek ten wykrywano w świeżo wyprodukowanym serze, natomiast pozostałe aminy pojawiały się stopniowo w czasie przechowywania. Największy wzrost stężenia w czasie przechowywania stwierdzono w przypadku putrescyny. Natomiast poziom spermidyny zmniejszał się w czasie przechowywania. Po 8 tygodniach przechowywania badane sery zawierały jednak nieznaczne ilości amin biogennych, w stężeniach dopuszczalnych przez normy UE i bezpiecznych dla ludzkiego zdrowia

Investigation of a cantilever structured piezoelectric energy harvester used for wearable devices with random vibration input

Abstract The capability of using a linear kinetic energy harvester — A cantilever structured piezoelectric energy harvester — to harvest human motions in the real-life activities is investigated. The whole loop of the design, simulation, fabrication and test of the energy harvester is presented. With the smart wristband/watch sized energy harvester, a root mean square of the output power of 50 μW is obtained from the real-life hand-arm motion in human’s daily life. Such a power is enough to make some low power consumption sensors to be self-powered. This paper provides a good and reliable comparison to those with nonlinear structures. It also helps the designers to consider whether to choose a nonlinear structure or not in a particular energy harvester based on different application scenarios