The Analysis And Prediction Of Seed Dispersal Patterns

Spatial patterns of sibling plants constitute unique microcosms for the study of plant population biology. I have developed the thesis that aspects of seed dispersal patterns may be predicted from a knowledge of parent plant architecture and that seed dispersal patterns may be used, in turn, to predict patterns of surviving offspring. Individuals from six distinct biotypes of Panicum miliaceum L. (Poaceae) were grown in three crop environments: oats, soybeans, and corn. Seed dispersal patterns and patterns of mature offspring were mapped using a contiguous grid of triangular sections. Plant architecture was described in terms of the spatial positions of the infructescences on each plant. Seed production and the morphology, palatability, and tannin chemistry of seeds were determined for every combination of biotype and crop environment.;Architectural characteristics (the height, lateral spread, and orientation of infructescences) were well correlated with both univariate and multivariate descriptions of seed dispersal patterns. Mean dispersal distance scaled to plant height in a power function relationship with an exponent of 0.67. This exponent did not differ significantly (p \u3e 0.05) from the value of 0.75 derived from an analytical model and an analysis of published data from a wide range of plants. In the latter analysis, propagule shape and size did not contribute significantly (p \u3e 0.05) to the prediction of mean dispersal distance.;The distance between a parent and a cohort of its offspring increased over the course of the cohort\u27s life cycle. Only cases with small sample sizes showed no significant (p \u3e 0.05) increase in cohort distance. The equivocation of previous reviews of this subject was criticized. No strong evidence was found in the literature for rejecting the hypothesis that the probability of plant survival increases with distance from an isolated parent. Multivariate evidence was given in support of the hypothesis that a greater proportion of mature offspring occur at a greater distance from the parent given a higher level of seed production

Efficient application switching with a single gesture

This disclosure describes techniques that enable switching between applications with a single gesture. The techniques can be implemented in any device that supports gestures, e.g., a mobile phone, tablet, laptop, etc. A user can switch between applications by performing a swipe gesture from an icon, e.g., a task switcher icon, or other location. In a touchscreen implementation, as the user’s finger moves, each available application window is briefly in focus. To switch to a target application, the user releases her finger. In this manner, a single continuous operation (swipe and release gesture) enables the user to switch between applications quickly and efficiently

In Situ Characterisation of Permanent Magnetic Quadrupoles for focussing proton beams

High intensity laser driven proton beams are at present receiving much attention. The reasons for this are many but high on the list is the potential to produce compact accelerators. However two of the limitations of this technology is that unlike conventional nuclear RF accelerators lasers produce diverging beams with an exponential energy distribution. A number of different approaches have been attempted to monochromise these beams but it has become obvious that magnetic spectrometer technology developed over many years by nuclear physicists to transport and focus proton beams could play an important role for this purpose. This paper deals with the design and characterisation of a magnetic quadrupole system which will attempt to focus and transport laser-accelerated proton beams.Comment: 20 pages, 42 figure

Cu-Doping Effects in CdI2Nanocrystals: The Role of Cu-Agglomerates

Cu-doping effects in CdI2nanocrystals are studied experimentally. We use the photostimulated second harmonic generation (PSSHG) as a tool to investigate the effects. It is found that the PSSHG increases with increasing Cu content up to 0.6% and then decreases due to the formation of the Cu-agglomerates. The PSSHG for the crystal with Cu content higher than 1% reduces to that for the undoped CdI2crystal. The results suggest that a crucial role of the Cu-metallic agglomerates is involved in the processes as responsible for the observed effects