Novel phosphite and nutrient application to control Phytophthora cinnamomi disease

Systemic treatment of stems with injections of phosphite liquid and novel soluble capsule implants of phosphite, PHOSCAP® (phosphorous, potassium, iron, manganese, zinc, boron, copper, magnesium and molybdenum) and MEDICAP MD® (nitrogen, phosphorous, potassium, iron, manganese, and zinc), were applied to Banksia grandis and Eucalyptus marginata trees to control Phytophthora cinnamomi. Four weeks after treatment application, excised branches were under-bark inoculated with P. cinnamomi. In B. grandis, phosphite implants and liquid injections significantly reduced lesion length compared to the control, and MEDICAP MD® implants; however, there was no significant difference in lesion length between trees treated with phosphite implants and liquid injections and PHOSCAP implants. In E. marginata, phosphite implants and liquid injections significantly reduced lesion length compared to the control, PHOSCAP® and MEDICAP MD® implants. In B. grandis and E. marginata, PHOSCAP® and MEDICAP MD® implants reduced the average lesion length compared to the control; however, the interactions were not significant. Results show that both liquid phosphite injections and novel phosphite implants are effective at controlling lesion extension in B. grandis and E. marginata, caused by P. cinnamomi. Further work is required to determine if nutrient application reduces Phytophthora disease through improving plant health

Acclimation responses of Arabidopsis thaliana to sustained phosphite treatments

Phosphite () induces a range of physiological and developmental responses in plants by disturbing the homeostasis of the macronutrient phosphate. Because of its close structural resemblance to phosphate, phosphite impairs the sensing, membrane transport, and subcellular compartmentation of phosphate. In addition, phosphite induces plant defence responses by an as yet unknown mode of action. In this study, the acclimation of Arabidopsis thaliana plants to a sustained phosphite supply in the growth medium was investigated and compared with plants growing under varying phosphate supplies. Unlike phosphate, phosphite did not suppress the formation of lateral roots in several Arabidopsis accessions. In addition, the expression of well-documented phosphate-starvation-induced genes, such as miRNA399d and At4, was not repressed by phosphite accumulation, whilst the induction of PHT1;1 and PAP1 was accentuated. Thus, a mimicking of phosphate by phosphite was not observed for these classical phosphate-starvation responses. Metabolomic analysis of phosphite-treated plants showed changes in several metabolite pools, most prominently those of aspartate, asparagine, glutamate, and serine. These alterations in amino acid pools provide novel insights for the understanding of phosphite-induced pathogen resistance

Pathogenicity of Phytophthora multivora to Eucalyptus gomphocephala and E. marginata

Since the early 1990s there has been a significant decline of E. gomphocephala, and more recently E. marginata, in the tuart forest in tuart woodland in Yalgorup National Park SW Western Australia, although no satisfactory aetiology has been established to explain the decline. Characteristics of the canopy dieback and decline distribution are reminiscent of other forest declines known to involve Phytophthora soil pathogens and indicate that a Phytophthora species may be involved in the decline. In 2007 isolates of Phytophthora multivora, recently described by (1), were recovered from rhizosphere soil of declining or dead trees of Eucalyptus gomphocephala and E. marginata. For E. gomphocephala and E. marginata, the pathogenicity of P. multivora was tested: ex situ on seedlings using a soil infestation method; and in situ on stems using an under bark infestation method

How do care partners of people with rare dementia use language in online peer support groups? A quantitative text analysis study

We used quantitative text analysis to examine conversations in a series of online support groups attended by care partners of people living with rare dementias (PLWRD). We used transcripts of 14 sessions (>100,000 words) to explore patterns of communication in trained facilitators’ (n = 2) and participants’ (n = 11) speech and to investigate the impact of session agenda on language use. We investigated the features of their communication via Poisson regression and a clustering algorithm. We also compared their speech with a natural speech corpus. We found that differences to natural speech emerged, notably in emotional tone (d = −3.2, p < 0.001) and cognitive processes (d = 2.8, p < 0.001). We observed further differences between facilitators and participants and between sessions based on agenda. The clustering algorithm categorised participants’ contributions into three groups: sharing experience, self-reflection, and group processes. We discuss the findings in the context of Social Comparison Theory. We argue that dedicated online spaces have a positive impact on care partners in combatting isolation and stress via affiliation with peers. We then discuss the linguistic mechanisms by which social support was experienced in the group. The present paper has implications for any services seeking insight into how peer support is designed, delivered, and experienced by participants

Phytophthora multivora sp. nov., a new species recovered from declining Eucalyptus, Banksia, Agonis and other plant species in Western Australia

A new Phytophthora species, isolated from rhizosphere soil of declining or dead trees of Eucalyptus gomphocephala, E. marginata, Agonis flexuosa, and another 13 plant species, and from fine roots of E. marginata and collar lesions of Banksia attenuata in Western Australia, is described as Phytophthora multivora sp. nov. It is homothallic and produces semipapillate sporangia, smooth-walled oogonia containing thick-walled oospores, and paragynous antheridia. Although morphologically similar to P. citricola, phylogenetic analyses of the ITS and cox1 gene regions demonstrate that P. multivora is unique. Phytophthora multivora is pathogenic to bark and cambium of E. gomphocephala and E. marginata and is believed to be involved in the decline syndrome of both eucalypt species within the tuart woodland in south-west Western Australia

Realising the Olympic dream: vision, support and challenge

The sporting arena is replete with examples and anecdotes of great inspirational coaches that have led teams to success, often in the face of adversity and against seemingly better opponents. The role of the coach in developing and motivating athletes has also been the focus of much research in sport psychology (e.g., Challaduria 1990; Smith & Smoll, 2007). Despite the ease with which one readily accepts that coaches can be inspirational, the sport coaching literature is somewhat devoid of research on inspirational coaches and the effects of such coaches on athletic success. The purpose of the current paper is to theoretically delineate the inspirational effects of coaches in sport. Given the relative paucity of inspiration-related research in sport we draw upon contemporary theories of leadership from organisational and military psychology (e.g., transformational and charismatic leadership theories). We propose a sport-specific model of leadership that centres around the vision, support, and challenge meta-cognitive model developed by Arthur and Hardy in military contexts. The model posits that �great� coaches inspire their athletes by: (a) creating an inspirational vision of the future; (b) providing the necessary support to achieve the vision; and (c) providing the challenge to achieve the vision. The underlying proposition is that the vision provides meaning and direction for followers� effort. That is, the vision serves as the beacon around which all the sweat, pain and sacrifice involved in achieving success at the highest level in sport is directed. At the heart of this model is the notion that athletes can achieve their dreams provided they are inspired to do so; this is because all other things being equal the person who is motivated to practice longer and train harder will ultimately be the best. The current paper will delineate the coach�s role in inspiring the athlete to train harder and longer

Non‐uniqueness and symmetry in stratigraphic interpretations:A quantitative approach for determining stratal controls

Different combinations of stratal controls could produce identical sequence architectures. Consequently, interpretations of the stratigraphic record, for example to infer palaeo-climate and eustatic sea-level history, suffer from non-uniqueness. However, variations in the multiple controls can be encapsulated through discovery of all possible solutions to an interpretation. As this paper demonstrates, a single solution can be directly transformed into an alternative solution that leaves the expected geological outcomes unaltered, which can be regarded as the existence of symmetry in the interpretation. Repetitive application of the symmetry method can therefore allow additional solutions to be rapidly derived given an existing solution. The proposed method has been adapted to a stratigraphic forward model for interpreting the Baltimore Canyon (USA) stratigraphy. Modelling results have indicated the ranges of changes in relative sea-level, sediment supply and subaerial erosion from Oligocene to Mid-Miocene. Using these limits, it is possible to determine what appears to be true in the palaeo-history, even when a solution is not unique

Hole-doping dependence of percolative phase separation in Pr_(0.5-delta)Ca_(0.2+delta)Sr_(0.3)MnO_(3) around half doping

We address the problem of the percolative phase separation in polycrystalline samples of Pr$_{0.5-\delta}$Ca$_{0.2+\delta}$Sr$_{0.3}$MnO$_3$ for $-0.04\leq \delta \leq 0.04$ (hole doping $n$ between 0.46 and 0.54). We perform measurements of X-ray diffraction, dc magnetization, ESR, and electrical resistivity. These samples show at $T_C$ a paramagnetic (PM) to ferromagnetic (FM) transition, however, we found that for $n>0.50$ there is a coexistence of both of these phases below $T_C$. On lowering $T$ below the charge-ordering (CO) temperature $T_{CO}$ all the samples exhibit a coexistence between the FM metallic and CO (antiferromagnetic) phases. In the whole $T$ range the FM phase fraction ($X$) decreases with increasing $n$. Furthermore, we show that only for $n\leq 0.50$ the metallic fraction is above the critical percolation threshold $X_C\simeq 15.5$. As a consequence, these samples show very different magnetoresistance properties. In addition, for $n\leq 0.50$ we observe a percolative metal-insulator transition at $T_{MI}$, and for $T_{MI}<T<T_{CO}$ the insulating-like behavior generated by the enlargement of $X$ with increasing $T$ is well described by the percolation law $\rho ^{-1}=\sigma \sim (X-X_C)^t$, where $t$ is a critical exponent. On the basis of the values obtained for this exponent we discuss different possible percolation mechanisms, and suggest that a more deep understanding of geometric and dimensionality effects is needed in phase separated manganites. We present a complete $T$ vs $n$ phase diagram showing the magnetic and electric properties of the studied compound around half doping.Comment: 9 text pages + 12 figures, submitted to Phys. Rev.

Phase fluctuations, dissipation and superfluid stiffness in d-wave superconductors

We study the effect of dissipation on quantum phase fluctuations in d-wave superconductors. Dissipation, arising from a nonzero low frequency optical conductivity which has been measured in experiments below $T_c$, has two effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction of the temperature at which one crosses over to classical thermal fluctuations. For parameter values relevant to the cuprates, we show that the crossover temperature is still too large for classical phase fluctuations to play a significant role at low temperature. Quasiparticles are thus crucial in determining the linear temperature dependence of the in-plane superfluid stiffness. Thermal phase fluctuations become important at higher temperatures and play a role near $T_c$.Comment: Presentation improved, new references added (10 latex pages, 3 eps figures). submitted to PR