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Ziziphus mauritiana methanol crude extract was evaluated for its insecticidal properties against Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquito larvae. Bioassays against larvae mosquitoes were done following World Health Organization’s guidelines. Late third and/or early fourth instar of mosquito larva were assayed for five different concentrations viz. 100, 150, 200, 250, and 300 mg ml–1 of Z. mauritiana crude extracts. From the results obtained, Aedes aegypti was the most susceptible to Z. mauritiana crude extracts. The percentage of mortality exhibited above 50% of 200, 250, and 300 mg ml–1 in 24, 48, and 72 hr exposure. Thus, it gives the lowest LC50 within 24 hr of exposure (121.98 mg L–1), followed by Ae. albopictus (189.89 mg L–1) and Cx. quinquefasciatus (246.22 mg L–1). Observation of the morphology effect of the dead larvae shows Ae. aegypti was the most affected, followed by Ae. albopictus and Cx. quinquefasciatus. A ruptured midgut was observed in 100 and 200 mg ml–1 concentrations. In contrast, in higher concentrations of 300 mg ml–1, the abdominal segments were indistinguishable, and the head and thorax regions were severely damaged. This study suggested that Z. mauritiana methanolic crude extracts were potent against Ae. aegypti larvae mosquitoes and have the potential to be used as an alternative larvicide in population control. However, further studies are required to establish the potential of Z. mauritiana larvicidal effects in the field setting.

The aim of this study was to evaluate the in vitro activity of Melaleuca cajuputi essential oil leaf extract against Aedes aegypti and Aedes albopictus. The essential oil of the M. cajuputi was obtained via steam hydro-distillation and analyzed by GC-MS for the chemical constituents. GC-MS analysis showed that the essential oil of M. cajuputi contained 13 compounds with two major chemical constituents, 2-propenoic acid (29.55%) and caryophyllene (20.04%). Adulticidal and larvicidal bioassay was evaluated following WHO guidelines. Larvicidal bioassays were conducted with the 10, 50, 80, 100, and 120 mg/L M. cajuputi essential oil against late 3rd instar of Ae. aegypti and Ae. albopictus which give LC50 120.99 mg/L and 222.58 mg/L, respectively. Adult mortality was observed after 24 h with the LC50 of 0.029 mg/cm2 for Ae. aegypti and 0.028 mg/cm2 for Ae. albopictus. In adulticidal bioassay, M. cajuputi essential oils showed effective results at 0.04 mg/cm2 concentrations, with values for KT50 of 77.71 min for Ae. aegypti and 69.49 min for Ae. albopictus. M. cajuputi essential oils exhibited moderate toxicity effects against the larva and adults of Aedes species and may be used as an alternative to chemical insecticide.

A novel structured of nanoporous vanadyl 2,11,20,29-Tetra Tert-Butyl 2,3 Naphthalocyanine (VTTBNc) films were prepared by template-assisted method. The structure and morphology of the fabricated VTTBNc nanostructures were studied by field emission scanning electron microscopy (FESEM) and micro-Raman spectroscopy. The VTTBNc nano-porous films showed a potential application in humidity sensors. 2017 Elsevier B.V. We would like to acknowledge University Malaya Research Grant (RP026C-15AFR) and Fundamental Research Grant Scheme (FP046-2015A) for project funding. Appendix A Scopus

Background: Melaleuca cajuputi essential oil in aerosol spray was evaluated against the dengue vectors Aedes ae­gypti and Ae. albopictus at low cost housing flats in Section 10, Setapak, Kuala Lumpur, Malaysia. Methods: Essential oil in aerosol viz: 5% and 10% of concentrations were sprayed for 5 seconds each towards hung mos­quitoes in 5 cylindrical net cages. Aerosol weights were recorded before and after spraying to determine dis­charge rates. Knockdown and mortality number were observed and compared to MS standard aerosol which contain 0.07% prallethrin and 0.05% d-phenothrin as positive control and aerosol contain 40% kerosene and 60% LPG was used as negative control. Results: High knockdown and mortality was observed in both species of mosquitoes towards MS standard aerosol. There was a significant difference (P