32,164 research outputs found
USE OF CONSERVATION RESERVE PROGRAM LAND FOR BIOREFINERY FEEDSTOCK PRODUCTION
Legislation passed in 2002 enables managed harvesting and grazing of Conservation Reserve Program (CRP) land, including harvesting of biomass. The objective of the research is to determine the cost to acquire, harvest, store, and deliver a steady flow of biomass from CRP grasslands to a biorefinery.Resource /Energy Economics and Policy,
The psychological-type profile of lay church leaders in Australia
A sample of 845 lay church leaders (444 women and 401 men) from a range of 24 different denominations and movements (including house churches and independent churches) completed the Francis Psychological-Type Scales within the context of the 2006 Australian National Church Life Survey. The psychological-type profiles of these lay church leaders were almost identical to the type profiles of 1527 Australian churchgoers (936 women and 591 men) published in an earlier study by Robbins and Francis. The predominant types among female lay church leaders were ISFJ (21%), ESFJ (21%), and ISTJ (18%). The predominant types among male lay church leaders were ISTJ (28%), ISFJ (17%), ESTJ (13%), and ESFJ (12%). The SJ temperament accounted for 67% of the female lay church leaders and for 70% of the male lay church leaders. The strengths and weaknesses of the SJ leadership style are discussed
The Williams Scale of Attitude toward Paganism: development and application among British Pagans
This article builds on the tradition of attitudinal measures of religiosity established by Leslie Francis and colleagues with the Francis Scale of Attitude toward Christianity (and reflected in the Sahin-Francis Scale of Attitude toward Islam, the Katz-Francis Scale of Attitude toward Judaism, and the Santosh-Francis Scale of Attitude toward Hinduism) by introducing a new measure to assess the attitudinal disposition of Pagans. A battery of items was completed by 75 members of a Pagan Summer Camp. These items were reduced to produce a 21-item scale that measured aspects of Paganism concerned with: the God/Goddess, worshipping, prayer, and coven. The scale recorded an alpha coefficient of 0.93. Construct validity of the Williams Scale of Attitude toward Paganism was demonstrated by the clear association with measures of participation in private rituals
Validity of the Cauchy-Born rule applied to discrete cellular-scale models of biological tissues
The development of new models of biological tissues that consider cells in a discrete manner is becoming increasingly popular as an alternative to PDE-based continuum methods, although formal relationships between the discrete and continuum frameworks remain to be established. For crystal mechanics, the discrete-to-continuum bridge is often made by assuming that local atom displacements can be mapped homogeneously from the mesoscale deformation gradient, an assumption known as the Cauchy-Born rule (CBR). Although the CBR does not hold exactly for non-crystalline materials, it may still be used as a first order approximation for analytic calculations of effective stresses or strain energies. In this work, our goal is to investigate numerically the applicability of the CBR to 2-D cellular-scale models by assessing the mechanical behaviour of model biological tissues, including crystalline (honeycomb) and non-crystalline reference states. The numerical procedure consists in precribing an affine deformation on the boundary cells and computing the position of internal cells. The position of internal cells is then compared with the prediction of the CBR and an average deviation is calculated in the strain domain. For centre-based models, we show that the CBR holds exactly when the deformation gradient is relatively small and the reference stress-free configuration is defined by a honeycomb lattice. We show further that the CBR may be used approximately when the reference state is perturbed from the honeycomb configuration. By contrast, for vertex-based models, a similar analysis reveals that the CBR does not provide a good representation of the tissue mechanics, even when the reference configuration is defined by a honeycomb lattice. The paper concludes with a discussion of the implications of these results for concurrent discrete/continuous modelling, adaptation of atom-to-continuum (AtC) techniques to biological tissues and model classification
Environmental Consequences of Ethanol from Corn Grain, Ethanol from Lignocellulosic Biomass, and Conventional Gasoline
The Energy Policy Act of 2005 includes a provision designed to double the production and use of ethanol in fuels by 2012, and that beginning in 2013, a minimum of 250 million gallons per year of ethanol be produced from lignocellulosic sources such as corn stover, wheat straw, and switchgrass. This study was conducted to determine the environmental and health consequences of using ethanol as an additive to gasoline. Comparisons are made among conventional gasoline (CG), a blend of 10 percent corn-ethanol and 90 percent CG (E10-corn), and a blend of 10 percent ethanol produced from lignocellulosic biomass (LCB) and 90 CG (E10-LCB).Resource /Energy Economics and Policy,
Conventional Tillage versus No-till: Characteristics of Producers and Farms
A survey of Oklahoma farmers was conducted to determine characteristics of farms across three tillage categories: conventional tillage exclusively; no-till exclusively; other (combination of systems). The seven percent that use no-till exclusively crop more acres, rent more acres, and use more crop rotations than farms that use conventional tillage exclusively.no-till, conventional tillage, survey, farm machinery, farm size, wheat, perceptions, Crop Production/Industries, Farm Management, Q10, Q12,
Solute transport within porous biofilms: diffusion or dispersion?
Many microorganisms live within surface-associated consortia, termed biofilms, that can form intricate porous structures interspersed with a network of fluid channels. In such systems, transport phenomena, including flow and advection, regulate various aspects of cell behaviour by controllling nutrient supply, evacuation of waste products and permeation of antimicrobial agents. This study presents multiscale analysis of solute transport in these porous biofilms. We start our analysis with a channel-scale description of mass transport and use the method of volume averaging to derive a set of homogenized equations at the biofilmscale. We show that solute transport may be described via two coupled partial differential equations for the averaged concentrations, or telegrapher’s equations. These models are particularly relevant for chemical species, such as some antimicrobial agents, that penetrate cell clusters very slowly. In most cases, especially for nutrients, solute penetration is faster, and transport can be described via an advection-dispersion equation. In this simpler case, the effective diffusion is characterised by a second-order tensor whose components depend on: (1) the topology of the channels’ network; (2) the solute’s diffusion coefficients in the fluid and the cell clusters; (3) hydrodynamic dispersion effects; and (4) an additional dispersion term intrinsic to the two-phase configuration. Although solute transport in biofilms is commonly thought to be diffusion-dominated, this analysis shows that dispersion effects may significantly contribute to transport
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Developing and evaluating interventions to reduce inappropriate prescribing by general practitioners of antibiotics for upper respiratory tract infections: a randomised controlled trial to compare paper-based and web-based modelling experiments
Background: Much implementation research is focused on full-scale trials with little evidence of preceding modelling work. The Medical Research Council Framework for developing and evaluating complex interventions has argued for more and better theoretical and exploratory work prior to a trial as a means of improving intervention development. Intervention modelling experiments (IMEs) are a way of exploring and refining an intervention before moving to a full-scale trial. They do this by delivering key elements of the intervention in a simulation that approximates clinical practice by, for example, presenting general practitioners (GPs) with a clinical scenario about making a treatment decision.
Methods: The current proposal will run a full, web-based IME involving 250 GPs that will advance the methodology of IMEs by directly comparing results with an earlier paper-based IME. Moreover, the web-based IME will evaluate an intervention that can be put into a full-scale trial that aims to reduce antibiotic prescribing for upper respiratory tract infections in primary care. The study will also include a trial of email versus postal invitations to participate.
Discussion: More effective behaviour change interventions are needed and this study will develop one such intervention and a system to model and test future interventions. This system will be applicable to any situation in the National Health Service where behaviour needs to be modified, including interventions aimed directly at the public.
Trial registration: ClinicalTrials (NCT): NCT0120673
Low-Metallicity Gas Clouds in a Galaxy Proto-Cluster at Redshift 2.38
We present high resolution spectroscopy of a QSO whose sight-line passes
through the halo of a pair of elliptical galaxies at redshift 2.38. This pair
of galaxies probably lies at the center of a galaxy proto-cluster, and is
embedded in a luminous extended Ly-alpha nebula.
The QSO sight-line intersects two small gas clouds within this halo. These
clouds have properties similar to those of high velocity clouds (HVCs) seen in
the halo of the Milky Way. The gas is in a cool (< 2 x 10^4 K) and at least 20%
neutral phase, with metallicities in the range -3.0 < [Fe/H] < -1.1 and neutral
hydrogen column densities of ~10^19.5 /cm^2.
The origin of these clouds is unclear. The presence of low metallicity gas
within this possible proto-cluster implies either that the intra-cluster medium
has not been enriched with metals at this redshift, or the clouds are embedded
within a hot, ionized, metal-rich gas phase.Comment: Accepted to appear in ApJ Letter
Contacting the spirits of the dead: paranormal belief and the teenage worldview
A number of previous studies have examined both the overall level of belief expressed by young people in the paranormal and the major demographic predictors of such belief. Building on this research tradition, the present study examines how one specific paranormal belief concerning contact with the spirits of the dead integrates with the wider teenage worldview. Data provided by 33,982 pupils age 13 to 15 years throughout England and Wales demonstrated that almost one in three young people (31%) believed that it is possible to contact the spirits of the dead. Compared with young people who did not share this belief, the young people who believed in the possibility of contacting the spirits of the dead displayed lower psychological wellbeing, higher anxiety, greater isolation, greater alienation, less positive social attitudes, and less socially conforming lifestyles. Overall, paranormal beliefs seem to be associated with a less healthy worldview, in both personal and social terms
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