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Polyaniline (PANI) is typically a conductive polymer which has a uniqueness in structure and physical properties. The physical properties generally can be controlled by introducing a specific dopant as well as other processing parameters. This polymer has been widely investigated and applied in various fields, especially in electronics. Some metallic elements have been introduced to modified its characteristic such as iron and copper. In order to improve the characteristic of this material, it is important to study the optimum process as well as the elemental substitution of PANI films. In this study, we report the influence of employing sonochemistry technic and the silver substitution on the crystallinity and electrical conductivity of PANI/Ni films. The samples have been prepared similarly to the previous report with silver doped in the range of 0.1 [?] x [?] 0.5 M. Other series of the sample were also prepared at various irradiation time of ultrasonic exposure. FTIR spectra showed that EB and ES Polyanilines had been successfully synthesized. X-RD histogram also revealed that crystallinity of the films comparably increased with the increase ultrasonic irradiation time as well as the silver in dopant. Along with the crystallinity, the electrical conductivity of films also increased as an increase of the dopant and of ultrasonic irradiation time.

Novel approaches to suppress dengue and other mosquito-borne diseases involve changing the composition of mosquito vector populations, particularly through Wolbachia endosymbionts. The success of these strategies depends on understanding the dynamics of vector populations. In preparation for Wolbachia releases around Yogyakarta, we have studied Aedes populations in five hamlets. Adult monitoring with BioGent-Sentinel (BG-S) traps indicated that hamlet populations had different dynamics across the year; while there was an increase in Aedes aegypti (L.) and Aedes albopictus (Skuse) numbers in the wet season, species abundance remained relatively stable in some hamlets but changed markedly (>2 fold) in others. Local rainfall a month prior to monitoring partly predicted numbers of Ae. aegypti but not Ae. albopictus. Site differences in population size indicated by BG-S traps were also evident in ovitrap data. Egg or larval collections with ovitraps repeated at the same location suggested spatial autocorrelation (<250 m) in the areas of the hamlets where Ae. aegypti numbers were high. Overall, there was a weak negative association (r < −0.43) between Ae. aegypti and Ae. albopictus numbers in ovitraps when averaged across collections. Ae. albopictus numbers in ovitraps and BG-S traps were positively correlated with vegetation around areas where traps were placed, while Ae. aegypti were negatively correlated with this feature. These data inform intervention strategies by defining periods when mosquito densities are high, highlighting the importance of local site characteristics on populations, and suggesting relatively weak interactions between Ae. aegypti and Ae. albopictus. They also indicate local areas within hamlets where consistently high mosquito densities may influence Wolbachia invasions and other interventions.