Curtin University

About: Curtin University is a education organization based out in Perth, Western Australia, Australia. It is known for research contribution in the topics: Population & Zircon. The organization has 14257 authors who have published 48997 publications receiving 1336531 citations. The organization is also known as: WAIT & Western Australian Institute of Technology.

Plant structural traits and their role in anti-herbivore defence

Abstract: We consider the role that key structural traits, such as spinescence, pubescence, sclerophylly and raphides, play in protecting plants from herbivore attack. Despite the likelihood that many of these morphological characteristics may have evolved as responses to other environmental stimuli, we show that each provides an important defence against herbivore attack in both terrestrial and aquatic ecosystems. We conclude that leaf-mass–area is a robust index of sclerophylly as a surrogate for more rigorous mechanical properties used in herbivory studies. We also examine herbivore counter-adaptations to plant structural defence and illustrate how herbivore attack can induce the deployment of intensified defensive measures. Although there have been few studies detailing how plant defences vary with age, we show that allocation to structural defences is related to plant ontogeny. Age-related changes in the deployment of structural defences plus a paucity of appropriate studies are two reasons why relationships with other plant fitness characteristics may be obscured, although we describe studies where trade-offs between structural defence and plant growth, reproduction, and chemical defences have been demonstrated. We also show how resource availability influences the expression of structural defences and demonstrate how poorly our understanding of plant structural defence fits into contemporary plant defence theory. Finally, we suggest how a better understanding of plant structural defence, particularly within the context of plant defence syndromes, would not only improve our understanding of plant defence theory, but enable us to predict how plant morphological responses to climate change might influence interactions at the individual (plant growth trade-offs), species (competition), and ecosystem (pollination and herbivory) levels.

Pre-nucleation clusters as solute precursors in crystallisation

Abstract: Crystallisation is at the heart of various scientific disciplines, but still the understanding of the molecular mechanisms underlying phase separation and the formation of the first solid particles in aqueous solution is rather limited. In this review, classical nucleation theory, as well as established concepts of spinodal decomposition and liquid–liquid demixing, is introduced together with a description of the recently proposed pre-nucleation cluster pathway. The features of pre-nucleation clusters are presented and discussed in relation to recent modifications of the classical and established models for phase separation, together with a review of experimental work and computer simulations on the characteristics of pre-nucleation clusters of calcium phosphate, calcium carbonate, iron(oxy)(hydr)oxide, silica, and also amino acids as an example of small organic molecules. The role of pre-nucleation clusters as solute precursors in the emergence of a new phase is summarized, and the link between the chemical speciation of homogeneous solutions and the process of phase separation via pre-nucleation clusters is highlighted.

N-Doping-Induced Nonradical Reaction on Single-Walled Carbon Nanotubes for Catalytic Phenol Oxidation

Abstract: Metal-free materials have been demonstrated to be promising alternatives to conventional metal-based catalysts. Catalysis on nanocarbons comparable to that of cobalt- or manganese-based catalysts in peroxymonosulfate (PMS) activation has been achieved, yet the catalyst stability has to be addressed and the mechanism also needs to be elucidated. In this study, N-doped carbon nanotubes (NoCNTs) were employed as metal-free catalysts for phenol catalytic oxidation with sulfate radicals and, more importantly, a detailed mechanism of PMS activation and the roles of nitrogen heteroatoms were comprehensively investigated. For the first time, a nonradical pathway accompanied by radical generation (•OH and SO4•–) in phenol oxidation with PMS was discovered upon nitrogen heteroatom doping. The NoCNTs presented excellent stability due to the emerging nonradical processes. The findings can be used for the design of efficient and robust metal-free catalysts with both superior catalytic performance and high stability fo...

Spatial Point Patterns: Methodology and Applications with R

Abstract: BASICS Introduction Point patterns Statistical methodology for point patterns About this book Software Essentials Introduction to RR Packages for R Introduction to spatstat Getting started with spatstat FAQ Collecting and Handling Point Pattern Data Surveys and experiments Data handling Entering point pattern data into spatstat Data errors and quirks Windows in spatstat Pixel images in spatstat Line segment patterns Collections of objects Interactive data entry in spatstat Reading GIS file formats FAQ Inspecting and Exploring Data Plotting Manipulating point patterns and windows Exploring images Using line segment patterns Tessellations FAQ Point Process Methods Motivation Basic definitions Complete spatial randomness Inhomogeneous Poisson process A menagerie of models Fundamental issues Goals of analysis EXPLORATORY DATA ANALYSIS Intensity Introduction Estimating homogeneous intensity Technical definition Quadrat counting Smoothing estimation of intensity function Investigating dependence of intensity on a covariate Formal tests of (non-)dependence on a covariate Hot spots, clusters, and local features Kernel smoothing of marks FAQ Correlation Introduction Manual methods The K-function Edge corrections for the K-function Function objects in spatstat The pair correlation function Standard errors and confidence intervals Testing whether a pattern is completely random Detecting anisotropy Adjusting for inhomogeneity Local indicators of spatial association Third- and higher-order summary statistics Theory FAQ Spacing Introduction Basic methods Nearest-neighbour function G and empty-space function F Confidence intervals and simulation envelopes Empty-space hazard J-function Inhomogeneous F-, G- and J-functions Anisotropy and the nearest-neighbour orientation Empty-space distance for a spatial pattern Distance from a point pattern to another spatial pattern Theory for edge corrections Palm distribution FAQ STATISTICAL INFERENCE Poisson Models Introduction Poisson point process models Fitting Poisson models in spatstat Statistical inference for Poisson models Alternative fitting methods More flexible models Theory Coarse quadrature approximation Fine pixel approximation Conditional logistic regression Approximate Bayesian inference Non-loglinear models Local likelihood FAQ Hypothesis Tests and Simulation Envelopes Introduction Concepts and terminology Testing for a covariate effect in a parametric model Quadrat counting tests Tests based on the cumulative distribution function Monte Carlo tests Monte Carlo tests based on summary functions Envelopes in spatstat Other presentations of envelope tests Dao-Genton test and envelopes Power of tests based on summary functions FAQ Model Validation Overview of validation techniques Relative intensity Residuals for Poisson processes Partial residual plots Added variable plots Validating the independence assumption Leverage and influence Theory for leverage and influence FAQ Cluster and Cox Models Introduction Cox processes Cluster processes Fitting Cox and cluster models to data Locally fitted models Theory FAQ Gibbs Models Introduction Conditional intensity Key concepts Statistical insights Fitting Gibbs models to data Pairwise interaction models Higher-order interactions Hybrids of Gibbs models Simulation Goodness-of-fit and validation for fitted Gibbs models Locally fitted models Theory: Gibbs processes Theory: Fitting Gibbs models Determinantal point processes FAQ Patterns of Several Types of Points Introduction Methodological issues Handling multitype point pattern data Exploratory analysis of intensity Multitype Poisson models Correlation and spacing Tests of randomness and independence Multitype Gibbs models Hierarchical interactions Multitype Cox and cluster processes Other multitype processes Theory FAQ ADDITIONAL STRUCTURE Higher-Dimensional Spaces and Marks Introduction Point patterns with numerical or multidimensional marks Three-dimensional point patterns Point patterns with any kinds of marks and coordinates FAQ Replicated Point Patterns and Designed Experiments Introduction Methodology Lists of objects Hyperframes Computing with hyperframes Replicated point pattern datasets in spatstat Exploratory data analysis Analysing summary functions from replicated patterns Poisson models Gibbs models Model validation Theory FAQ Point Patterns on a Linear Network Introduction Network geometry Data handling Intensity Poisson models Intensity on a tree Pair correlation function K-function FAQ