Strategies for wheat stripe rust pathogenicity identified by transcriptome sequencing

Stripe rust caused by the fungus Puccinia striiformis f.sp. tritici (Pst) is a major constraint to wheat production worldwide. The molecular events that underlie Pst pathogenicity are largely unknown. Like all rusts, Pst creates a specialized cellular structure within host cells called the haustorium to obtain nutrients from wheat, and to secrete pathogenicity factors called effector proteins. We purified Pst haustoria and used next-generation sequencing platforms to assemble the haustorial transcriptome as well as the transcriptome of germinated spores. 12,282 transcripts were assembled from 454-pyrosequencing data and used as reference for digital gene expression analysis to compare the germinated uredinospores and haustoria transcriptomes based on Illumina RNAseq data. More than 400 genes encoding secreted proteins which constitute candidate effectors were identified from the haustorial transcriptome, with two thirds of these up-regulated in this tissue compared to germinated spores. RT-PCR analysis confirmed the expression patterns of 94 effector candidates. The analysis also revealed that spores rely mainly on stored energy reserves for growth and development, while haustoria take up host nutrients for massive energy production for biosynthetic pathways and the ultimate production of spores. Together, these studies substantially increase our knowledge of potential Pst effectors and provide new insights into the pathogenic strategies of this important organism.J.P.R. is an ARC Future Fellow (FT0992129). This project has been supported by Bioplatforms Australia through funding from the Commonwealth Government NCRIS and Education Investment Fund Super Science programs

Construction Of User-Friendly Plant Expression Vectors Using Rice Promoters

This project (3 months duration) was embedded within our ongoing projects on “Rice Functional Genomics”. A PhD student, Andrew Eamens was employed in this project to continue work on the development of user friendly plant expression vectors based on rice promoters. This work was started towards the end of Andrew’s PhD studentship. Using reporter genes containing a minimal promoter (enhancer trap) or intron splice acceptors (gene trap) in T-DNA or transposon tagging systems, several promoter sequences were identified by Andrew during his doctoral research and were used to produce plant expression vectors with tissue specific expression. The previously developed double right boarder (DRB) vector technology was used to construct a small group of user-friendly plant expression vectors with tissue-specific expression promoters. A new base binary vector construct (PDRB12dn) was constructed during this project period. The binary vector contained a promoterless reporter gene (sgfpS65T) mounted between the second right border (RB2) and the T-DNA left border (LB). The reporter gene is flanked upstream by a multiple cloning site (MCS) containing several unique restriction enzyme (RE) cleavage sites for easy cloning of putative promoter fragments. A total of 12 promoter fragments were also amplified by the polymerase chain reaction (PCR), ready for addition to the base vector. Cloning of individual promoter fragments is now in progress. The plant expression constructs being produced will enable the production of selectable marker free transgenic plants expressing GOIs in specific cells, tissues or organs

Analytical and numerical solutions to describe water table fluctuations due to canal seepage and time-varying recharge

Abstract Hybrid finite analytic solution (HFAS), Galerkin\u27s method based finite element solution (FES) and fully implicit finite difference solution (FIFDS) of one dimensional nonlinear Boussinesq equation and Analytical solution of Boussinesq equation linearized by Baumann\u27s transformation (analytical solution I, AS I) as well as linearized by Werner\u27s transformation (analytical solution II, AS II) were employed to obtain water table rise in a horizontal unconfined aquifer lying between two canals located at finite distance having different elevations and subjected to various patterns of recharge, i.e. zero recharge, constant recharge, as well as time varying recharge. Considering HFAS as benchmark solution, water table in mid region as obtained from FES followed by FIFDS was observed quite close to that obtained from HFAS and as per L2 and Tchebycheff norms computation, it was ranked at first and second place, respectively. Both AS I and AS II predicted higher water table at t = 5 days but at t = 10 days, AS I predicted lower and AS II predicted higher water table at all distances due to linearization effect. So, analytical solutions of linearized Boussinesq equation were rated lower than numerical solutions of nonlinear Boussinesq equation

Fuzzy logic based robotic controller

Existing Proportional-Integral-Derivative (PID) robotic controllers rely on an inverse kinematic model to convert user-specified cartesian trajectory coordinates to joint variables. These joints experience friction, stiction, and gear backlash effects. Due to lack of proper linearization of these effects, modern control theory based on state space methods cannot provide adequate control for robotic systems. In the presence of loads, the dynamic behavior of robotic systems is complex and nonlinear, especially where mathematical modeling is evaluated for real-time operators. Fuzzy Logic Control is a fast emerging alternative to conventional control systems in situations where it may not be feasible to formulate an analytical model of the complex system. Fuzzy logic techniques track a user-defined trajectory without having the host computer to explicitly solve the nonlinear inverse kinematic equations. The goal is to provide a rule-based approach, which is closer to human reasoning. The approach used expresses end-point error, location of manipulator joints, and proximity to obstacles as fuzzy variables. The resulting decisions are based upon linguistic and non-numerical information. This paper presents a solution to the conventional robot controller which is independent of computationally intensive kinematic equations. Computer simulation results of this approach as obtained from software implementation are also discussed

Validation of a laboratory method for evaluating dynamic properties of reconstructed equine racetrack surfaces.

BackgroundRacetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.ObjectiveTo develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.MethodsTrack-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.ResultsMost dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.ConclusionsLaboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).Potential relevanceDynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions

Magnetic field effects on spin texturing in a quantum wire with Rashba spin-orbit interaction

A quantum wire with strong Rashba spin-orbit interaction is known to exhibit spatial modulation of spin density along its width owing to coupling between subbands caused by the Rashba interaction. This is known as spin texturing. Here, we show that a transverse external magnetic field introduces additional complex features in spin texturing, some of which reflect the intricate details of the underlying energy dispersion relations of the spin-split subbands. One particularly intriguing feature is a 90° phase shift between the spatial modulations of two orthogonal components of the spin density, which is observed at moderate field strengths and when only the lowest spin-split level is occupied by electrons. Its origin lies in the fact that the Rashba interaction acts as an effective magnetic field whose strength is proportional to the electron’s velocity

The impact of COVID-19 on the practice of Oral and Maxillofacial Pathology in the United States and Canada

Background: The COVID-19 pandemic has significantly disrupted the delivery of healthcare, including oral healthcare services. The restrictions imposed for mitigating spread of the virus forced dental practitioners to adopt significant changes in their workflow pattern. The aim of this study was to investigate the impact of the pandemic on the practice of oral and maxillofacial pathology in two countries in regard to educational activities, and clinical and diagnostic pathology services

Fabrication of Epitaxial Thin Films by Pulsed Laser Deposition and Structural Studies of (Ba0.85Ca0.15)(Zr0.10Ti0.90)O3: a Lead Free Piezoelectric

After the discovery of piezoelectricity in 1880 by Curie brothers, the drive for basic science behind the phenomenon and utilization for new applications begun. Later the discovery of PZT (Lead Zirconate Titanate) led to saturation in further discoveries because of its superior piezoelectric properties. But the presence of lead in PZT is known to be hazardous to the environment. Hence, the need for lead free piezoelectric materials arose. In 2009 Wenfeng Liu reported high dielectric constant value in lead free piezoelectric materials Ba0.85Ca0.15Zr0.10Ti0.90O3 (BCZT). The basic approach to achieving high piezoelectricity is to place the composition of the material to the proximity of a composition- induced phase transition between two ferroelectric phases. Easy domain switching with low energy barrier was the reason for high piezoelectric constants values in BCZT. Later BCZT has been extensively studied in bulk but the field of BCZT thin films still needs to be studied for both fundamental aspects and applications

Plant species composition and product utility pattern of Garo homegardens in Meghalaya, India

Home garden is a traditional landuse system practiced by many rural households in the tropical region. The composition and management practices within homegardens are largely driven by cultural setup and ecological conditions. The present study characterized the plant species composition, utility patterns and management of  Garo homegardens in Dadenggre block, West Garo Hill district of Meghalaya, India. Fifty households from 5 villages were randomly selected and interviewed using a semi-structured questionnaire. The homegardens size ranged between 0.07 and 1.29ha, harbouring 132 plant species, out of which 74 species were trees, 19 shrubs and 39 herbs. Among the perennials, Areca catechu (areca nut) was the most common contributor to household earnings. When species were grouped into 9 utility classes (timber, medicinal, fruit, fuelwood, fodder, vegetables, ornamental, spice, and others), highest number was for fuelwood, followed by vegetables and fruits. The average household income was Rs. 318/100m2, the highest contribution from the sale of vegetables. Various home garden management activities were conducted, engaging family members and generating employment for others. Animal rearing is common in many households and the application of animal manure and household waste has helped maintain soil fertility of homegardens’ soils. Homegardens are integral to the Garo society, contributing significantly to household needs and activities.