Dry heat disinfection versus seed borne Fusarium – six years of practical experience

Non-Peer Reviewe

Multidimensional Coherent Spectroscopy of a Semiconductor Microcavity

Rephasing and non-rephasing two-dimensional coherent spectra map the anti-crossing associated with normal-mode splitting in a semiconductor microcavity. For a 12-meV detuning range near zero detuning, it is observed that there are two diagonal features related to the intra-action of exciton-polariton branches and two off-diagonal features related to coherent interaction between the polaritons. At negative detuning, the lineshape properties of the diagonal intra-action features are distinguishable and can be associated with cavity-like and exciton-like modes. A biexcitonic companion feature is observed, shifted from the exciton feature by the biexciton binding energy. Closer to zero detuning, all features are enhanced and the diagonal intra-action features become nearly equal in amplitude and linewidth. At positive detuning the exciton- and cavity-like characteristics return to the diagonal intra-action features. Off-diagonal interaction features exhibit asymmetry in their amplitudes throughout the detuning range. The amplitudes are strongly modulated (and invert) at small positive detuning, as the lower polariton branch crosses the bound biexciton energy determined from negative detuning spectra.Comment: 13 pages, 4 figure

Uniform CPA Examination/May 1980-November 1984, Auditing: Selected Questions and Unofficial Answers Indexed to Content Specification Outline

https://egrove.olemiss.edu/aicpa_exam/1247/thumbnail.jp

Bayesian networks for assessment of disruption to school systems under combined hazards

Exposure of school buildings to floods and earthquakes poses significant risk to the vulnerable population of students and their education process. In regions of high exposure, these hazards may often act concurrently, whereby yearly flood events weaken masonry school buildings, rendering them more vulnerable to frequent earthquake shaking. This recurring damage, combined with other functional losses, ultimately result in disruption to education delivery. The socio-economic condition of the users-community also plays a role in the extent of such disruption. A complex problem of this nature demands consideration of a large number of dimensions, to estimate the impact to the school system infrastructure in a locality. To handle the qualitative and quantitative nature of these variables, a Bayesian network (BN) model is proposed representing multiple schools in a locality as a system. Three dimensions are considered to contribute to the system disruption, namely, schools’ physical functionality loss, accessibility and use loss, and social vulnerability. The impact is quantified through the probability of the system being in various states of disruption. The BN also explores mitigating measures, such as the mobility of students between schools in the system. The general methodology is illustrated by a case-study of school buildings in Guwahati, India, whereby the majority of buildings is constructed in confined masonry with varying level of seismic performance. The physical effects of combined flood and seismic action on confined masonry buildings is assessed by nonlinear numerical modelling, and their probabilistic occurrence is expressed in terms of fragility functions corresponding to varying flood depth and peak ground acceleration

Influence of pesticides on pathogen populations and biological control agents

Non-Peer Reviewe

Agent-based model on resilience-oriented rapid responses of road networks under seismic hazard

This paper explores a new pathway towards seismic resilience of Road Networks (RNs) under earthquake hazards, by leveraging post-shock rapid responses as the key to minimize the functionality losses of RNs, especially in the immediate aftermath of earthquakes. Accordingly, an agent-based modelling (ABM) framework is developed to enable the nuanced examination on resilience of earthquake-damaged RNs, when different system repair approaches are considered. In this framework, those different approaches are predicated on the damage level of individual bridges and on the system recovery timeline, i.e. the response to rehabilitation need is considered as a function of the time elapsed from the event. Each approach is represented by a different agent, whose behaviour is shaped by a set of pre-defined behavioural attributes, while the interplay among those agents is also accounted for, during the entirety of post-shock recovery campaigns. To demonstrate its applicability, the ABM framework is applied to a real-world RN across Luchon, France. As shown by the case-study, post-shock rapid responses are found to be a viable strategy to increase the recovery rate of RNs’ functionality in the immediate-, and mid-term aftermath of damaging earthquakes, and ultimately, to improve the seismic resilience thereof

Tillage system and cropping sequence effects on common root rot of barley in eastern Saskatchewan

Non-Peer ReviewedFusarium head blight (FHB) in barley has been spreading on the Canadian Prairies for the last decade. Fusarium spp. causing FHB can also cause crown/root rot of cereal crops. It is therefore of interest to determine the impact of agronomic practices on fungal populations associated with root rot of barley. From 1999 to 2001, 137 barley crops were sampled in eastern Saskatchewan for severity of subcrown internode discoloration and percent isolation of fungi. Cochliobolus sativus was the most commonly isolated fungus, whereas the most commonly isolated Fusarium spp. included the FHB pathogens F. avenaceum, F. culmorum and F. graminearum. Discoloration caused by C. sativus was favored by conventional-till, whereas Fusarium spp. increased in reduced tillage systems. Barley grown after a cereal-summerfallow (or summefallow-cereal) sequence under conventional- or minimum-till had increased levels of C. sativus. Fusarium spp. were most affected by the previously grown crop(s); they were more common in barley grown after a noncereal than a cereal, and after two noncereals, or a noncereal alternated with summerfallow. Previous glyphosate applications were associated with lower C. sativus, and higher Fusarium spp., levels in barley grown under minimum till. This suggests changes in fungal communities; however, the mechanism(s) responsible for these changes in fungal levels are not known. Increased infection of ground/underground tissue by FHB pathogens might contribute to its development in succeeding cereal crops, therefore measures aimed at reducing root/crown infections by Fusarium spp. might also help reduce FHB development

Tillage system and cropping sequence effects on Fusarium head blight in barley in eastern Saskatchewan

Non-Peer ReviewedFusarium head blight (FHB) in barley is well established in the eastern Canadian Prairies and appears to be moving westward. A survey of 192 barley crops in eastern Saskatchewan was conducted to determine the impact of agronomic practices on FHB (1999-2002) and Fusarium damaged kernels (FDK) (2000-2001). The most common species isolated from spikes/kernels were F. sporotrichioides, F. avenaceum, and F. graminearum, followed by F. poae and F. culmorum. Disease tended to be higher under minimum- than conventional- and/or zero-till. F. sporotrichioides was favored by a previous cereal crop, whereas F. avenaceum was higher after a pulse crop, and F. graminearum decreased after a pulse but not an oilseed crop. The latter two pathogens were also more prevalent after diversified cropping sequences than after two cereal crops. Summerfallow, or summerfallow alternated with cereals, decreased FDK. Previous glyphosate (Group 9 herbicides) use was associated with increased infection by all Fusarium spp., whereas Group 1 herbicides were associated with increased infection by F. poae and F. sporotrichioides. Number of previous glyphosate applications was also correlated with FHB caused by F. avenaceum and F. graminearum. We concluded that in eastern Saskatchewan, barley grown under minimum-till where glyphosate had been sprayed and following diversified cropping sequences would sustain the greatest damage due to FHB/FDK caused by F. avenaceum and F. graminearum

Rapid earthquake loss updating of spatially distributed systems via sampling-based bayesian inference

Within moments following an earthquake event, observations collected from the affected area can be used to define a picture of expected losses and to provide emergency services with accurate information. A Bayesian Network framework could be used to update the prior loss estimates based on ground-motion prediction equations and fragility curves, considering various field observations (i.e., evidence). While very appealing in theory, Bayesian Networks pose many challenges when applied to real-world infrastructure systems, especially in terms of scalability. The present study explores the applicability of approximate Bayesian inference, based on Monte-Carlo Markov-Chain sampling algorithms, to a real-world network of roads and built areas where expected loss metrics pertain to the accessibility between damaged areas and hospitals in the region. Observations are gathered either from free-field stations (for updating the ground-motion field) or from structure-mounted stations (for the updating of the damage states of infrastructure components). It is found that the proposed Bayesian approach is able to process a system comprising hundreds of components with reasonable accuracy, time and computation cost. Emergency managers may readily use the updated loss distributions to make informed decisions