Some factors affecting the establishment and growth of bud grafts of roses : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Botany at Massey University

A brief review of abnormal growth of rose scion buds and the high proportion of buds which fail to produce normal growth in the production of rose plants by bud-grafting in New Zealand, introduces the subject. The history of investigations, prior to 1968, into this problem is outlined. A description of normal growth patterns of shoots on roses, of axillary buds and of production methods in New Zealand is followed by a detailed description of the abnormal teratomatous growth, known as proliferation, which is characteristic of a proportion of affected buds. The proposal is put forward that this condition is caused by infection with an organism that initiates galling similar in appearance to crown gall and that subsequent symptoms develop consequent to such a tumorous transformation but not necessarily due to the continued presence of the causal organism. In this study no causal organism was successfully isolated. The claims of a number of possible other causal agents are examined including development of the graft union, chemical factors, non-transforming bacteria, mites, fungi and viruses. Reasons are advanced why none of these provide a satisfactory explanation in agreement with experimental and observational evidence. This evidence is discussed in relation to the etiology and development of the disease syndrome. The evidence presented is strongly in support of a tumorous transformation, initiated by a soil-borne pathogen, occurring at the proximal end of the original stock cutting at the time of its insertion in the ground. Root initiation may be restricted by the position of the gall and the first shoot growth at the top of the stock may show slight symptoms. The infected plant is predisposed to show subsequent symptoms but these are dependent on subsequent operations and the time and conditions when they are carried out. These symptoms are the development of excessive callus at the point of excision of the stock top and at the incision of the bud-graft, the production of teratomatous shoots, known as proliferation, by the scion bud or failure of the scion bud to grow despite a successful graft union. These symptoms may be reduced or prevented by successful normal growth of the scion. A comparison of the etiology and development of the syndrome of proliferation disease is made with the classical characteristics of the crown gall syndrome. Recent research publications on crown gall are reviewed to establish that recent findings are not contrary to the proposal that rose proliferation disease is caused in a manner directly analagous to crown gall. It is proposed that the evidence supports the assumption that a particular strain of Agrobacterium tumefaciens or some bacterium closely related to it is the etiological agent causing rose proliferation disease

The atrial T wave: The elusive electrocardiographic wave exposed by a case of shifting atrial pacemaker

The atrial T wave (Ta wave) is the body surface manifestation of atrial repolarisation and, unlike the P wave (atrial depolarisation), is little recognised. We report the case of a patient with shifting pacemaker which clearly demonstrates the effect of the Ta wave on ST segment and T wave. A simple conceptual model is used to explain the observed phenomenon. The case serves as a reminder of this often forgotten ECG wave and its potential effects on other ECG features

Futures in primary science education – connecting students to place and ecojustice

After providing a background to futures thinking in science, and exploring the literature around transdisciplinary approaches to curriculum, we present a futures pedagogy. We detail case studies from a year-long professional learning action research project during which primary school teachers developed curriculum for the Anthropocene, focusing on the topic of fresh water. Why fresh water? Living in South Australia—the driest state in the driest continent—water is a scarce and precious resource, and our main water supply, the River Murray, is in trouble. Water is an integral part of Earth’s ecosystem and plays a vital role in our survival (Flannery, 2010; Laszlo, 2014). Water literacy therefore has a genuine and important place in the school curriculum.Working with teachers and their students, the Water Literacies Project provided an ideal opportunity to explore a range of pedagogical approaches and practices which connect students to their everyday world, both now and in their possible futures, through place-based learning. We describe the use of futures scenario writing in an issues-based transdisciplinary curriculum unit on the theme of Water, driven by Year 5 teachers and their students from three primary schools: two located on the River Murray and one near metropolitan Adelaide. All three schools focused on a local wetland. The research was informed by teacher interviews, student and teacher journals, student work samples, and teacher presentations at workshops and conferences. We report on two aspects of the project: (1) the implementation of futures pedagogy, including the challenges it presented to the teachers and their students and (2) an emerging analysis of students’ views of the future and implications for further work around the futures pedagogical framework. Personal stories in relation to water, prior knowledge on the nature of water, experiential excursions to learn about water ecology and stories that examine the cultural significance of water—locally and not so locally—are featured (Lloyd, 2011; Paige & Lloyd, 2016). The outcome of our project is the development of comprehensive adventurous transdisciplinary units of work around water and connection to local place

A habitat-use model to determine essential fish habitat for juvenile brown shrimp (Farfantepenaeus aztecus) in Galveston Bay, Texas

A density prediction model for juvenile brown shrimp (Farfantepenaeus aztecus) was developed by using three bottom types, five salinity zones, and four seasons to quantify patterns of habitat use in Galveston Bay, Texas. Sixteen years of quantitative density data were used. Bottom types were vegetated marsh edge, submerged aquatic vegetation, and shallow nonvegetated bottom. Multiple regression was used to develop density estimates, and the resultant formula was then coupled with a geographical information system (GIS) to provide a spatial mosaic (map) of predicted habitat use. Results indicated that juvenile brown shrimp (0.50. These results indicate that this model may have a broader geographic application and is a plausible approach in refining current EFH designations for all Gulf of Mexico estuaries with similar geomorphological and hydrological characteristics

Generalized support and formal development of constraint propagators

Constraint programming is a family of techniques for solving combinatorial problems, where the problem is modelled as a set of decision variables (typically with finite domains) and a set of constraints that express relations among the decision variables. One key concept in constraint programming is propagation: reasoning on a constraint or set of constraints to derive new facts, typically to remove values from the domains of decision variables. Specialized propagation algorithms (propagators) exist for many classes of constraints.The concept of support is pervasive in the design of propagators. Traditionally, when a domain value ceases to have support, it may be removed because it takes part in no solutions. Arc-consistency algorithms such as AC2001 make use of support in the form of a single domain value. GAC algorithms such as GAC-Schema use a tuple of values to support each literal. We generalize these notions of support in two ways. First, we allow a set of tuples to act as support. Second, the supported object is generalized from a set of literals (GAC-Schema) to an entire constraint or any part of it.We design a methodology for developing correct propagators using generalized support. A constraint is expressed as a family of support properties, which may be proven correct against the formal semantics of the constraint. We show how to derive correct propagators from the constructive proofs of the support properties. The framework is carefully designed to allow efficient algorithms to be produced. Derived algorithms may make use of dynamic literal triggers or watched literals for efficiency. Finally, three case studies of deriving efficient algorithms are given

First complete pterosaur from the Afro-Arabian continent : insight into pterodactyloid diversity

Despite being known from every continent, the geological record of pterosaurs, the first group of vertebrates to develop powered flight, is very uneven, with only a few deposits accounting for the vast majority of specimens and almost half of the taxonomic diversity. Among the regions that stand out for the greatest gaps of knowledge regarding these flying reptiles, is the Afro-Arabian continent, which has yielded only a small number of very fragmentary and incomplete materials. Here we fill part of that gap and report on the most complete pterosaur recovered from this continent, more specifically from the Late Cretaceous (~95 mya) Hjoûla Lagerstätte of Lebanon. This deposit is known since the Middle Ages for the exquisitely preserved fishes and invertebrates, but not for tetrapods, which are exceedingly rare. Mimodactylus libanensis gen. et sp. nov. differs from the other Afro-Arabian pterosaur species named to date and is closely related to the Chinese species Haopterus gracilis, forming a new clade of derived toothed pterosaurs. Mimodactylidae clade nov. groups species that are related to Istiodactylidae, jointly designated as Istiodactyliformes (clade nov.). Istiodactyliforms were previously documented only in Early Cretaceous sites from Europe and Asia, with Mimodactylus libanensis the first record in Gondwana

Dynamic/Jitter Assessment of Multiple Potential HabEx Structural Designs

One of the driving structural requirements of the Habitable Exo-Planet (HabEx) telescope is to maintain Line Of Sight (LOS) stability between the Primary Mirror (PM) and Secondary Mirror (SM) of 5 mas. Dynamic analyses of two configurations of a proposed (HabEx) 4 meter off-axis telescope structure were performed to predict effects of jitter on primary/secondary mirror alignment. The dynamic disturbance used as the forcing function was the James Webb Space Telescope reaction wheel assembly vibration emission specification level. The objective of these analyses was to predict "order-of-magnitude" performance for various structural configurations which will roll into efforts to define the HabEx structural design's global architecture. Two variations of the basic architectural design were analyzed. Relative motion between the PM and the SM for each design configuration are reported