Adult Plant Resistance to Fungal Pathogens of Wheat

There is evidence that wheat, as well as containing genes for resistance, also contains genes that promote susceptibility to disease. Mutagenesis of the variety Hobbit 'sib' produced a number of lines with increased resistance to yellow rust (Worland & Law, 1991). The aim of this research was to characterise the resistance of the Hobbit 'sib' mutants, to identify and map the mutations and to determine which conferred resistance. The incidence of genes promoting susceptibility in other varieties also formed part of the investigation since manipulation of these genes may enable the resistance of commercial varieties to be improved. Significantly improved resistance to yellow rust relative to Hobbit 'sib' was demonstrated in 17 of the 21 mutants investigated, confirming the previous findings of Worland & Law, 1991 (IAEA Vienna, Mutation Breeding Newsletter 38: pp2 - 5). Furthermore, resistance to brown rust and mildew was also demonstrated in a subset of mutants, with one mutant, 13-48, exhibiting high levels of resistance to all three diseases. The broad spectrum of resistance in 13-48 suggests that mutation has inactivated either a single gene for susceptibility with a common effect on all three diseases, or a number of genes for susceptibility, each specific for a different disease. No mutants were identified with significantly improved resistance to Stagonospora nodorum or Septoria tritici, suggesting that this method of inducing resistance may only be of value for obligate pathogens. Using molecular techniques, deletions were identified in 12 mutant lines, and the deletions were spread throughout the genome. Several mutant lines contained more than one deletion. "Representational Difference Analysis" was used successfully to identify deletions in selected mutants and, in contrast to using RFLP probes, provided a more targeted approach to identifying deletions irrespective of chromosome location. Analysis of the segregation of deletion markers in F2 populations segregating for disease resistance identified a deletion on 4DL of 13-48 that segregated with yellow rust and brown rust resistance. This was due to linkage in the case of brown rust resistance, but the yellow rust resistance may be due directly to the deletion, possibly as a consequence of the removal of a gene for susceptibility to this disease. A number of deletions were identified, both in 13-48 and other mutants, that did not segregate with resistance. Therefore, the deletion markers may be useful both as tags facilitating the selection of deletions conferring resistance, and also for the removal of deletions not implicated in improving resistance. The distribution of genes for susceptibility in several varieties, most of which are in commercial use, was examined using either segregational tests for allelism or backcross reciprocal monosomie analysis in order to identify targets for disease resistance improvement. Both these approaches proved to be unsuccessful. The reasons for this failure are presented and possible solutions described. The nature and possible roles of genes for susceptibility are discussed

Observations on the early public health movement in Scotland

The observations which follow represent a.n attempt to arrive at an understanding of certain aspects of the background to the early public health movement which seemed obscure. By all accounts the 18th century in Scotland represented a period of material progress and increasing prosperity. The economic advance continued in the early 19th century, yet the rise in the prosperity of the people did not seem to keep pace with it. The investigations into the conditions of the people in the 1830's, which played such an important part in the sanitary reform movement, indicated an actual deterioration in welfare for many of the common folk. This association of increasing economic power and diminishing prosperity seemed anomalous at first glance: and the fact of a break in the upward trend of general prosperity was difficult to accept without further study.in attempting to understand these difficulties, the first step was to examine events during the 18th century to find out whether the supposed improvement in the welfare of the people during that period was genuine. for this purpose the increase in population which took place during that century was selected for special study, and an attempt was made to discover the causes of this increase. The next step was to look into conditions in the early 19th century to find out whether or not a deterioration actually did take place at that time. Ioor this purpose certain trends of the death rates and the incidence of disease were examined: and the environment and financial condition of parts of the population were investigated. ï+finally an attempt was made to arrive at an understanding of the history of some of the early developments in public health reform in Scotland in the light of such facts as had been elucidated

Intermolecular N-H...O=C hydrogen bonding in the crystal structure of 6-amino-1,3-dimethyluracil

The 6-amino- 1,3-dimethyluracil molecule [6-amino- 1,3- dimethyl-2,4(1H,3H)-pyrimidinedione], C6H9N302 (I), lies on a crystallographic mirror plane and participates in an extensive two-dimensional hydrogen-bonding network in the solid state. Each molecule is involved in N-- H...O=C hydrogen bonding involving the amino and carbonyl gr. oups, with O...N separations of 2.894 (3) and 2.904 (3) A

Towards a relevant architecture : an international rowing and canoeing regatta centre for KwaZulu-Natal, South Africa.

Thesis (M.Arch.)-University of KwaZulu-Natal, Durban, 2010.2008 was a year which highlighted how far South Africa has fallen behind the rest of the world in the international Olympic sporting arena. High hopes for the Olympic Games in Beijing ended in a lower-than expected medal tally that sparked great debate in South African society. The reasons for this phenomenon are numerous and complex and it is not the intention of this dissertation to investigate all these concerns. However, what is of an architectural concern is the inadequate and often sub-standard sporting facilities which athletes in South Africa, in non-mainstream sporting codes, have to contend with. The challenge for architects in this regard is to design buildings for these sports, that are both adequate and of a suitable standard, while remaining relevant to their context. This to promote professionalism and inspire athletes to succeed through the creation of high quality, world-class facilities for competition, training and preparation. Rowing, canoeing and kayaking are highly competitive and technologically advanced Olympic sports. Many South African athletes compete in these disciplines and have enjoyed limited international success. Unfortunately, as there are currently no international regatta centres in Southern Africa, these same athletes have to travel abroad to compete and train at such facilities. South African athletes and the sports of rowing, canoeing and kayaking would thus benefit greatly from having access to locally based regatta facilities. KwaZulu-Natal has a proud sporting heritage and is synonymous with water sports as a result of its favourable climate and geographic location. This coupled with various other established sporting infrastructure, makes it the ideal Province for hosting major sporting events. Both Durban as a city and KwaZulu-Natal as a Province, have an impressive track record for hosting large sporting events. The Province has future aspirations of hosting major sporting events including the Commonwealth Games and the Olympics Games, with Durban soon hoping to be bidding to host the 2020 Summer Olympics. To host such events will require the design of many specialised sporting facilities for the city and will include the need for an international regatta centre. In my opinion, the best site for such a centre in KwaZulu-Natal is at Camps Drift in Pietermaritzburg. The requirements for an international regatta centre are both highly technical and very specific as set out by the respective world sporting governing bodies. These requirements need to be strictly adhered to in order for the Centre to be considered to be of an internationalstandard. The challenge will be to design architecture that is functional in achieving these set criteria while, remaining relevant to the social, economic and environmental context of its design. Thus the purpose of this research document is to determine a relevant architecture for the design of an International Regatta Centre for KwaZulu-Natal

Unsupervised Deformable Image Registration for Respiratory Motion Compensation in Ultrasound Images

In this paper, we present a novel deep-learning model for deformable registration of ultrasound images and an unsupervised approach to training this model. Our network employs recurrent all-pairs field transforms (RAFT) and a spatial transformer network (STN) to generate displacement fields at online rates (apprx. 30 Hz) and accurately track pixel movement. We call our approach unsupervised recurrent all-pairs field transforms (U-RAFT). In this work, we use U-RAFT to track pixels in a sequence of ultrasound images to cancel out respiratory motion in lung ultrasound images. We demonstrate our method on in-vivo porcine lung videos. We show a reduction of 76% in average pixel movement in the porcine dataset using respiratory motion compensation strategy. We believe U-RAFT is a promising tool for compensating different kinds of motions like respiration and heartbeat in ultrasound images of deformable tissue

Cube Analyzer - A Medical Image Analysis Program

The Cube Analyzer is a group of programs designed to analyze three-dimensional tomographic data such as CT, PET and MRI scans. It is designed to work on a Unix workstation running X-windows, and was programmed in C. Cube Analyzer provides the user with an interactive system by which he can view the scans, define regions of interest (ROI), and extract data. The system can be used alone to analyze images, or combined with the elastic matching software package to analyze computer-generated ROI\u27s

A High Throughput Aqueous Passivation Testing Methodology for Compositionally Complex Alloys using Scanning Droplet Cell

Compositionally complex alloy systems containing more than five principal elements allow exploring a wide range of compositions, processing, and structural variables with the hope for identifying unique properties. Such opportunities also apply to designing materials for improved corrosion resistance, regulated by a self-healing passive film. Such a rich landscape in reactivity and protectivity demands the search for high-throughput experimental testing workflows to uncover key metrics, indicative of superior properties. In this communication, one such methodology is demonstrated for evaluating passivation performance of a combinatorial library of Al0.7-x-yCoxCryFe0.15Ni0.15 thin film alloys in deaerated 0.1 mol/L H2SO4(aq), using a scanning droplet cell

Appendicitis and abdominal pain: A critical re-examination of the pathology of the appendix and of the clinical management of abdominal pain

Abstract Not Provided