The mechanosensitive (MS) channels MscS and MscL are essential for the survival of hypoosmotic shock by Escherichia coli cells. We demonstrate that MscS and MscL are induced by osmotic stress and by entry into stationary phase. Reduced levels of MS proteins and reduced expression of mscL-and mscS-LacZ fusions in an rpoS mutant strain suggested that the RNA polymerase holoenzyme containing S is responsible, at least in part, for regulating production of MS channel proteins. Consistent with the model that the effect of S is direct, the MscS and MscL promoters both use RNA polymerase containing S in vitro. Conversely, clpP or rssB mutations, which cause enhanced levels of S , show increased MS channel protein synthesis. RpoS null mutants are sensitive to hypoosmotic shock upon entry into stationary phase. These data suggest that MscS and MscL are components of the RpoS regulon and play an important role in ensuring structural integrity in stationary phase bacteria.

Design of reliable wireless sensor network (WSN) need to address the failure of single or multiple network components and implementation of the techniques to tolerate the faults occurred at various levels. The issues and requirements of reliability improvement mechanism depend on the available resources and application for which the WSN is deployed. This paper discusses the different modeling approaches to evaluate the reliability and classification of the approaches to improve it. Also the paper analyzes reliability enhancement by existing fault tolerant methods in WSN and compares the performance of these techniques with the technique we developed. From the results of the analysis we highlight the challenges and the characteristics of the sensor network affects the reliability and give some scope of future research directions in order to enhance reliability.

Cryptolestes ferrugineus is a serious cosmopolitan pest of stored products. Frequent and indiscriminate usage of phosphine has caused the development of high levels of resistance to this fumigant. As there are few alternatives, it is imperative that resistance to phosphine is managed. Effective management requires knowledge of key factors driving the rate of selection. One of the most important factors is the response of each resistance genotype to phosphine, especially heterozygotes. Moreover, it is important to understand the expression of resistance in all life stages as all stages are subjected to selection during fumigation. We determined the relative tolerance and resistance levels to phosphine in all life stages of homozygous parental strains (susceptible and resistant) and their F 1 progeny (heterozygous) and estimated relative dominance of resistance within life stages over 48 h. In susceptible insects, relative tolerance was highest in eggs followed by pupae, then adults which had about the same tolerance as larvae. In homozygous resistant insects, the order of tolerance was adult = egg [ pupae [ larvae and in heterozygotes larvae [ eggs [ pupae [ adults. All life stages expressed resistance with resistance ratios highest in adults [ pupae [ larvae [ eggs. At LC 50 , resistance was incompletely recessive in eggs, pupae and adults and incompletely dominant in larvae. Eggs and adults were also incompletely recessive at LC 95 , but larvae were completely dominant and pupae were incompletely dominant. Our data showed that a proportion of heterozygotes in all life stages, the major carriers of resistance in the field, will survive at very high concentrations, particularly in the egg stage, forming a nucleus for reinfestation or dispersal of resistance.

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41The rice weevil, Sitophilus oryzae is one of the primary pests of stored grains worldwide. To 42 develop and implement an effective integrated pest management strategy, an understanding of the 43 population structuring of this destructive pest is vital. In this study we used Illumina paired-end 44 sequencing to develop S. oryzae species-specific microsatellite markers, and used these markers to 45 conduct a preliminary assessment of population structuring in four populations of S. oryzae from three 46 countries (Australia, China, and USA). 7,635,996 raw sequencing reads were produced, with 11,794 47 microsatellites detected and 214,257 primer options designed. 48 microsatellite markers were selected 48 for further validation, with 10 markers amplifying consistently across the four S. oryzae populations. 49These markers displayed a high level of polymorphism overall (6.67 alleles/locus), though this was 50 slightly lower within populations (3.10 -4.88 alleles/locus). We used the markers to conduct a 51 preliminary assessment of genetic structuring among the four S. oryzae populations: three laboratory 52 cultures (New South Wales, Queensland, and Santai) and a field collected population from Kansas. 53 Analyses suggest high levels of genetic differentiation between the sample locations, with a global F ST 54 of 0.239, and pairwise F ST values ranging from 0.100 to 0.395. Bayesian clustering analyses suggest 55 these four populations formed four distinct clusters, with a similar pattern identified by Principal 56 Coordinate Analysis. These microsatellite markers, together with our preliminary population genetic 57 analyses, will provide a valuable resource for population genetic research, and contribute to effective 58 integrated pest management strategies in the future. 59 60 61 62 63 4