First Report of Leptomantispa pulchella (Banks, 1912) (Neuroptera: Mantispidae) from Iowa

An adult specimen of Leptomantispa pulchella (Banks) (Neuroptera: Mantispidae) was collected in southeast Iowa. Published records indicate the species is present in southwestern Canada and much of Central America, but this is the first published report of this species from Iowa

Chronic fatigue syndrome; an approach combining self-management with graded exercise to avoid exacerbations.

Controversy regarding the aetiology and treatment of patients with chronic fatigue syndrome (CFS) continues to affect the medical professions. The Cochrane collaboration advises practitioners to implement graded exercise therapy for CFS sufferers using cognitive behavioural principles. In contrast there is evidence that exercise can induce symptom exacerbations in CFS where too vigorous exercise/activity promotes immune dysfunction, which in turn increases symptoms in patients with CFS. When designing and implementing an exercise programme it is important to be aware of both these seemingly opposing view points in order to deliver a programme without any detrimental effects on CFS pathophysiology. Using evidence from both the biological and clinical sciences, the present manuscript explains that graded exercise therapy for people with CFS can be safely undertaken without detrimental effects to the immune system. Exercise programs should be designed to cater for individual physical capabilities and should also account for the fluctuating nature of symptoms commonly reported by people with CFS. In line with cognitive behaviourally and graded exercise-based strategies, self-management for people with CFS involves encouraging the patients to pace their activities and respect their physical and mental limitations with the ultimate aim of improving their everyday function

Organic conversion strategies for stockless farming systems

This report was presented at the UK Organic Research 2002 Conference. The identification of appropriate stockless organic conversion strategies will help farmers and growers in their decision to convert to organic production. The current practice of a two-year red clover/ryegrass ley conversion relies on subsidies to be economically viable. This standard conversion and six alternatives were tested on a sandy loam soil entering organic conversion. A test crop of winter wheat will be grown across the entire experimental area in the first fully organic year (2001/2002). Strategies containing a legume ley phase returned the greatest amount of nitrogen to the soil. At the end of the second year, pre-cultivation, there were no differences in soil mineral nitrogen between strategies. Gross margins were greater from those strategies with cash cropping than those without, in spite of the generally depressed yields. Preliminary analysis suggests that growing red clover for seed in year 1 followed by a red clover ley in year 2 could be the most profitable option

MODELING SPATIAL DEPENDENCE AND SPATIAL HETEROGENEITY IN COUNTY YIELD FORECASTING MODELS

The implications of ignoring potential spatial dependence in county-level yield data are discussed. Spatial dependence in a county-level yield data set is identified and methods for correcting the dependence via spatial weighting matrices and generalized least squares regression are performed. The paper also examines how the spatial dependence declines as the distance between observations increases.Productivity Analysis, Research Methods/ Statistical Methods,

Orthorhombic Phase of Crystalline Polyethylene: A Monte Carlo Study

In this paper we present a classical Monte Carlo simulation of the orthorhombic phase of crystalline polyethylene, using an explicit atom force field with unconstrained bond lengths and angles and periodic boundary conditions. We used a recently developed algorithm which apart from standard Metropolis local moves employs also global moves consisting of displacements of the center of mass of the whole chains in all three spatial directions as well as rotations of the chains around an axis parallel to the crystallographic c-direction. Our simulations are performed in the NpT ensemble, at zero pressure, and extend over the whole range of temperatures in which the orthorhombic phase is experimentally known to be stable (10 - 450 K). In order to investigate the finite-size effects in this extremely anisotropic crystal, we used different system sizes and different chain lengths, ranging from C_12 to C_96 chains, the total number of atoms in the super-cell being between 432 and 3456. We show here the results for structural parameters, such as the orthorhombic cell parameters a,b,c, and the setting angle of the chains, as well as internal parameters of the chains, such as the bond lengths and angles. Among thermodynamic quantities, we present results for thermal expansion coefficients, elastic constants and specific heat. We discuss the temperature dependence of the measured quantities as well as the related finite-size effects. In case of lattice parameters and thermal expansion coefficients, we compare our results to those obtained from other theoretical approaches as well as to some available experimental data. We also suggest some possible ways of extending this study.Comment: 27 pages, RevTex, 24 figures, submitted to Journal of Chemical Physic