Low temperature/short duration steaming as a sustainable method of soil disinfection

This report was presented at the UK Organic Research 2002 Conference. Soil samples containing resting structures of fungal crop pathogens (Verticillium dahliae, Sclerotinia sclerotiorum, Sclerotium cepivorum, Pythium ultimum), potato cyst nematodes (Globodera rostochiensis and Globodera pallida) and weeds (Chenopodium album and Agropyron repens) were treated with aerated steam in the laboratory at temperatures ranging from 50–80oC in a specially constructed apparatus. Steaming at 50 or 60oC for three minutes, followed by an eight-minute resting period in the steamed soil and immediate removal from the soil thereafter, resulted in 100% kill of all weeds, fungi and nematodes. Low temperature/ short duration soil steaming could become a sustainable alternative to chemical or high-temperature steam soil disinfestation

Excitation spectrum of bosons in a finite one-dimensional circular waveguide via the Bethe ansatz

The exactly solvable Lieb-Liniger model of interacting bosons in one-dimension has attracted renewed interest as current experiments with ultra-cold atoms begin to probe this regime. Here we numerically solve the equations arising from the Bethe ansatz solution for the exact many-body wave function in a finite-size system of up to twenty particles for attractive interactions. We discuss the novel features of the solutions, and how they deviate from the well-known string solutions [H. B. Thacker, Rev. Mod. Phys.\ \textbf{53}, 253 (1981)] at finite densities. We present excited state string solutions in the limit of strong interactions and discuss their physical interpretation, as well as the characteristics of the quantum phase transition that occurs as a function of interaction strength in the mean-field limit. Finally we compare our results to those of exact diagonalization of the many-body Hamiltonian in a truncated basis. We also present excited state solutions and the excitation spectrum for the repulsive 1D Bose gas on a ring.Comment: 13 pages, 12 figure

Spatial and temporal filtering of a 10-W Nd:YAG laser with a Fabry-Perot ring-cavity premode cleaner

We report on the use of a fixed-spacer Fabry–Perot ring cavity to filter spatially and temporally a 10-W laser-diode-pumped Nd:YAG master-oscillator power amplifier. The spatial filtering leads to a 7.6-W TEMinfinity beam with 0.1% higher-order transverse mode content. The temporal filtering reduces the relative power fluctuations at 10 MHz to 2.8 x 10^-/sqrtHz, which is 1 dB above the shot-noise limit for 50 mA of detected photocurrent

Brain Injury Clubhouses

The National Institutes of Health (NIH) reported that the number of people living with permanent disability from brain injury grows annually as medical technology has advanced in life saving techniques. However, community-based programs which enable brain injury survivors to live productive lives throughout the entire course of recovery have not grown proportionately to meet this the need. Brain Injury Clubhouses were developed to address the need for coordinated, long-term, community-based supports for brain survivors in a community-based setting. Brain Injury Clubhouses are designed to improve the lives of persons with ABI and reduce strain on caregivers and healthcare services The information in this research brief is designed to provide funders, administrators, policy makers, and other stakeholders with an overview of Brain Injury Clubhouses. The brief also provides outcomes associated with participation in a Brain Injury Clubhouse from a recent research study to provide stakeholders with a better understanding of Brain Injury Clubhouses

Integral representations for correlation functions of the XXZ chain at finite temperature

We derive a novel multiple integral representation for a generating function of the \s^z-\s^z correlation functions of the spin-\2 XXZ chain at finite temperature and finite, longitudinal magnetic field. Our work combines algebraic Bethe ansatz techniques for the calculation of matrix elements with the quantum transfer matrix approach to thermodynamics.Comment: 33 pages, 2 figures, v2: 2 typos corrected, 1 figure adde

The O(2) model in polar coordinates at nonzero temperature

We study the restoration of spontaneously broken symmetry at nonzero temperature in the framework of the O(2) model using polar coordinates. We apply the CJT formalism to calculate the masses and the condensate in the double-bubble approximation, both with and without a term that explicitly breaks the O(2) symmetry. We find that, in the case with explicitly broken symmetry, the mass of the angular degree of freedom becomes tachyonic above a temperature of about 300 MeV. Taking the term that explicitly breaks the symmetry to be infinitesimally small, we find that the Goldstone theorem is respected below the critical temperature. However, this limit cannot be performed for temperatures above the phase transition. We find that, no matter whether we break the symmetry explicitly or not, there is no region of temperature in which the radial and the angular degree of freedom become degenerate in mass. These results hold also when the mass of the radial mode is sent to infinity.Comment: 23 pages, 10 figure

Evaluation of education and training in water and sanitation technology: case studies in Nepal and Peru

A significant constraint to effective and sustainable water and sanitation provision is the “lack of capacity at the local level” (WHO, 2010), however there is uncertainty in how the efforts of capacity builders should be measured, and improved (Brown, et al., 2001). The Centre for Affordable Water and Sanitation Technology (CAWST) and the Institute of Non-profit Studies at Mount Royal University (MRU) has collaborated to address this issue. An evaluative framework, based on the Kirkpatrick model (Kirkpatrick, D.L. & Kirkpatrick, J.D., 2006) was developed to assist capacity builders in the water and sanitation sector to capture and interpret the results of their education and training activities. The framework was applied to evaluate CAWST’s training activities in Peru and Nepal. The findings provide new perspectives on the impacts of CAWST’s work, and provide insight into how the framework can be valuable to other capacity building organizations

Automatic generation of alignments for 3D QSAR analyses

Many 3D QSAR methods require the alignment of the molecules in a dataset, which can require a fair amount of manual effort in deciding upon a rational basis for the superposition. This paper describes the use of FBSS, a pro-ram for field-based similarity searching in chemical databases, for generating such alignments automatically. The CoMFA and CoMSIA experiments with several literature datasets show that the QSAR models resulting from the FBSS alignments are broadly comparable in predictive performance with the models resulting from manual alignments