Development of a bacteriophage-based biopesticide for fire blight

Fire blight is an economically important disease of apples and pears that is caused by the bacterium Erwinia amylovora. Control of the disease depends on limiting primaly blosson1 infection in the spring, and rapidly removing infected tissue. The possibility of using phages to control E.amylovora populations has been suggested, but previous studies have. failed to show high treatment efficacies. This work describes the development of a phage-based biopesticide that controls E. amylovora populations under field conditions, and significantly reduces the incidence of fire blight. This work reports the first use ofPantoea agglomerans, a non-pathogenic relative ofE. amylovora, as a carrier for E. amylovora.phages. Its role is to support a replicating population of these phages on blossom surfaces during the period when the flowers are most susceptible to infection. Seven phages and one carrier isolate were selected for field trials from existing collections of 56 E. amylovora phages and 249 epiphytic orchard bacteria. Selection of the . /' phages and carrier was based on characteristics relevant to the production and field perfonnance of a biopesticide: host range, genetic diversity, growth under the conditions of large-scale production, and the ability to prevent E. amylovora from infecting pear blossoms. In planta assays showed that both the phages and the carrier make significant contributions to reducirig the development of fire blight symptoms in pear blossoms. Field-scale phage production and purification methods were developed based on the growth characteristics of the phages and bacteria in liquid culture, and on the survival of phages in various liquid media. Six of twelve phage-carrier biopesticide treatments caused statistically signiflcant reductions in disease incidence during orchard trials. Multiplex real-time PCR was used to simultaneously monitor the phage, carrier, and pathogen populations over the course of selected treatments. In all cases. the observed population dynamics of the biocontrol agents and the pathogen were consistent with the success or failure of each treatment to control disease incidence. In treatments exhibiting a significantly reduced incidel1ce of fire blight, the average blossom population ofE.amylovora had been reduced to pre-experiment epiphytic levels. In successful treatments the phages grew on the P. agglomerans carrier for 2 to 3 d after treatment application. The phages then grew preferentially on the pathogen, once it was introduced into this blossom ecosystem. The efficacy of the successful phage-based treatnlents was statistically similar to that of streptomycin, which is the most effective bactericide currently available for fire blight prevention. The in planta behaviour ofE. amylovora was compared to that ofErwinia pyrifoliae, a closely related species that causes fire blight-like synlptoms on pears in southeast Asia. Duplex real-time PCR was used to monitor the population dynamics of both species on single blossonls. E. amylovora exhibited a greater competitive fitness on Bartlett pear blossoms than E. pyrifoliae. The genome ofErwinia phage Ea21-4 was sequenced and annotated. Most of the 8-4.7 kB genome is substantially different from previously described sequences, though some regions are notably similar to Salmonella phage Felix 01 . Putative functions were assigned to approximately 30% of the predicted open reading frames based on amino acid sequence comparisons and N-terminal sequencing of structural proteins.

Analytical modelling of bacterial migration and accumulation with rate-limited sorption in discrete fractures

An analytical model for bacterial accumulation in a discrete fractllre has been developed. The transport and accumlllation processes incorporate into the model include advection, dispersion, rate-limited adsorption, rate-limited desorption, irreversible adsorption, attachment, detachment, growth and first order decay botl1 in sorbed and aqueous phases. An analytical solution in Laplace space is derived and nlln1erically inverted. The model is implemented in the code BIOFRAC vvhich is written in Fortran 99. The model is derived for two phases, Phase I, where adsorption-desorption are dominant, and Phase II, where attachment-detachment are dominant. Phase I ends yvhen enollgh bacteria to fully cover the substratllm have accllillulated. The model for Phase I vvas verified by comparing to the Ogata-Banks solution and the model for Phase II was verified by comparing to a nonHomogenous version of the Ogata-Banks solution. After verification, a sensitiv"ity analysis on the inpllt parameters was performed. The sensitivity analysis was condllcted by varying one inpllt parameter vvhile all others were fixed and observing the impact on the shape of the clirve describing bacterial concentration verSllS time. Increasing fracture apertllre allovvs more transport and thus more accllffilliation, "Vvhich diminishes the dllration of Phase I. The larger the bacteria size, the faster the sllbstratum will be covered. Increasing adsorption rate, was observed to increase the dllration of Phase I. Contrary to the aSSllmption ofllniform biofilm thickness, the accllffilliation starts frOll1 the inlet, and the bacterial concentration in aqlleous phase moving towards the olitiet declines, sloyving the accumulation at the outlet. Increasing the desorption rate, redllces the dliration of Phase I, speeding IIp the accllmlilation. It was also observed that Phase II is of longer duration than Phase I. Increasing the attachment rate lengthens the accliffililation period. High rates of detachment speeds up the transport. The grovvth and decay rates have no significant effect on transport, althollgh increases the concentrations in both aqueous and sorbed phases are observed. Irreversible adsorption can stop accllillulation completely if the vallIes are high.

William Hand Manufacturer of Fire-works, Pyrotechnic Artist Advertisement

An advertisement addressed to the "celebration committees" for May 24th and July 1st. William Hand details his services for fireworks and other lighting. Price ranges are included and reviews/comments quoted from several newspapers.

Cognitive Behavior Therapy for Obsessive-Compulsive Behavior in Children with Autism Spectrum Disorder: A Comparison of Hierarchical Linear Modelling and Visual Analysis

Behavioral researchers commonly use single subject designs to evaluate the effects of a given treatment. Several different methods of data analysis are used, each with their own set of methodological strengths and limitations. Visual inspection is commonly used as a method of analyzing data which assesses the variability, level, and trend both within and between conditions (Cooper, Heron, & Heward, 2007). In an attempt to quantify treatment outcomes, researchers developed two methods for analysing data called Percentage of Non-overlapping Data Points (PND) and Percentage of Data Points Exceeding the Median (PEM). The purpose of the present study is to compare and contrast the use of Hierarchical Linear Modelling (HLM), PND and PEM in single subject research. The present study used 39 behaviours, across 17 participants to compare treatment outcomes of a group cognitive behavioural therapy program, using PND, PEM, and HLM on three response classes of Obsessive Compulsive Behaviour in children with Autism Spectrum Disorder. Findings suggest that PEM and HLM complement each other and both add invaluable information to the overall treatment results. Future research should consider using both PEM and HLM when analysing single subject designs, specifically grouped data with variability.

Fire Insurance - Cowan & Parks 1851

A fire insurance policy in the amount of one thousand dollars through Aetna Insurance Company of Utica, New York. The cost of twenty two dollars and twenty five cents would give them a one year insurance policy from August 1851 through August 1852.

Towards Evaluating and Modelling the Impacts of Mobile-Based Augmented Reality Applications on Learning and Engagement

Mobile augmented reality applications are increasingly utilized as a medium for enhancing learning and engagement in history education. Although these digital devices facilitate learning through immersive and appealing experiences, their design should be driven by theories of learning and instruction. We provide an overview of an evidence-based approach to optimize the development of mobile augmented reality applications that teaches students about history. Our research aims to evaluate and model the impacts of design parameters towards learning and engagement. The research program is interdisciplinary in that we apply techniques derived from design-based experiments and educational data mining. We outline the methodological and analytical techniques as well as discuss the implications of the anticipated findings.

Towards Evaluating and Modelling the Impacts of Mobile-Based Augmented Reality Applications on Learning and Engagement

Mobile augmented reality applications are increasingly utilized as a medium for enhancing learning and engagement in history education. Although these digital devices facilitate learning through immersive and appealing experiences, their design should be driven by theories of learning and instruction. We provide an overview of an evidence-based approach to optimize the development of mobile augmented reality applications that teaches students about history. Our research aims to evaluate and model the impacts of design parameters towards learning and engagement. The research program is interdisciplinary in that we apply techniques derived from design-based experiments and educational data mining. We outline the methodological and analytical techniques as well as discuss the implications of the anticipated findings.

The salvo combat model with area fire

This paper analyzes versions of the salvo model of missile combat where area fire is used by one or both sides in a battle. While these models share some properties with the area fire Lanchester model and the aimed fire salvo model, they also display some interesting differences, especially over the course of several salvos. Whereas the relative size of each force is important with aimed fire, with area fire it is the absolute size that matters. Similarly, while aimed fire exhibits square law behavior, area fire shows approximately linear behavior. When one side uses area and the other uses aimed fire, the model displays a mix of square and linear law behavior.

Interlake Tissue Mills Fire Slides

The Interlake Tissue Mills storage location was at the intersection of Glendale and Merritt Street in Merritton. In the 1850s, the Beaver Cotton Mills (later Merritton Cotton Mills) was built. It was a frame building that burned down in 1881. A sandstone structure replaced the previous building. In 1906, the cotton mill closed and in 1912, the Independent Rubber Company took over the building. The mill was doubled in size. The rubber company remained there for ten years and then the building remained vacant until 1935. Interlake Tissue Mills acquired the building for storage purposes. A fire razed the larger of the plant’s buildings on Memorial Day weekend in 1961. After the fire, Domtar used the smaller building for storage for a short time. This is currently the site of the Keg Restaurant.

Letter to Robert Nelles from the Office of the N.D. Mutual Fire Insurance Company

Letter to Robert Nelles from the Office of the N.D. Mutual Fire Insurance Company regarding an assessment of 5% on the premium notes of this company. This is signed by Mr. Arnold, secretary of the N.D. Mutual F. Insurance Company, Dec. 15, 1849.

Insurance Policy from the Quebec Fire Assurance Company to Mr. Joseph Power Bradley

Insurance Policy from the Quebec Fire Assurance Company to Mr. Joseph Power Bradley for his household furniture, linen wearing apparels, glass, earthenware and printed books in a house occupied as a dwelling and belonging to Joseph Legare Junt in the town of Quebec, Oct. 10, 1830