1,845 research outputs found
Agricultural influences on carbon emissions and sequestration
This report was presented at the UK Organic Research 2002 Conference. Agricultural systems contribute to carbon emissions through several mechanisms: the direct use of fossil fuels in farm operations, the indirect use of embodied energy in inputs that are energy intensive to manufacture (e.g. fertilizers), and the cultivation of soils resulting in the loss of soil organic matter. However agriculture can also sequester carbon when organic matter accumulates in the soil or above-ground woody biomass acts as a permanent sink or is used as an energy source that substitutes for fossil fuels. The latest empirical data on agricultural carbon emissions and carbon sequestration opportunities in agricultural systems are reviewed and the necessary land use and management practices that will need to be employed to optimise carbon sequestration are considered
Producing the docile body: analysing Local Area Under-performance Inspection (LAUI)
Sir Michael Wilshaw, the head of the Office for Standards in Education (OfSTED), declared a 'new wave' of Local Area Under-performance Inspections (LAUI) of schools 'denying children the standard of education they deserve'. This paper examines how the threat of LAUI played out over three mathematics lessons taught by a teacher in her first year in the profession. A Foucauldian approach is mobilised with regard to disciplinary power and 'docile bodies'. The paper argues that, in the case in point, LAUI was a tool mediating performative conditions and, ultimately, the docile body. The paper will be of concern to policy sociologists, teachers, school leaders, and those interested in school inspection
Origin of the transient unpulsed radio emission from the PSR B1259-63 binary system
We discuss the interpretation of transient, unpulsed radio emission detected
from the unique pulsar/Be-star binary system PSR B1259-63. Extensive monitoring
of the 1994 and 1997 periastron passages has shown that the source flares over
a 100-day interval around periastron, varying on time-scales as short as a day
and peaking at 60 mJy (~100 times the apastron flux density) at 1.4 GHz.
Interpreting the emission as synchrotron radiation, we show that (i) the
observed variations in flux density are too large to be caused by the shock
interaction between the pulsar wind and an isotropic, radiatively driven,
Be-star wind, and (ii) the radio emitting electrons do not originate from the
pulsar wind. We argue instead that the radio electrons originate from the
circumstellar disk of the Be star and are accelerated at two epochs, one before
and one after periastron, when the pulsar passes through the disk. A simple
model incorporating two epochs of impulsive acceleration followed by
synchrotron cooling reproduces the essential features of the radio light curve
and spectrum and is consistent with the system geometry inferred from pulsed
radio data.Comment: To be published in Astrophysical Journal Letters 7 pages, 1
postscript figur
Soil health—a new challenge for microbiologists and chemists
Soil health refers to the biological, chemical, and physical features of soil that are essential to long-term, sustainable agricultural productivity with minimal environmental impact. Thus, soil health provides an overall picture of soil functionality. Although it cannot be measured directly, soil health can be inferred by measuring specific soil properties (e.g. organic matter content) and by observing soil status (e.g. fertility). There is also increased interest in studying soil microorganisms in their particular environments, as microbial diversity is intimately related to soil structure and function. One of the key objectives in determining soil health is to acquire indicators that can be used to evaluate the soil’s current status and hence to develop sustainable agricultural systems. In this regard, significant progress has been made over the last few years in the development of specific biomarkers and macromolecular probes, enabling rapid and reliable measurements of soil microbial communities. In addition, modern molecular biological techniques, such as fluorescence in situ hybridization (FISH), reverse transcriptase polymerase chain reaction (RT-PCR), denaturing gradient gel electrophoresis (DGGE), and terminal restriction fragment length polymorphism (T-RFLP), have facilitated the analysis of microbial biodiversity and activity, whereas the application of modern analytical techniques, such as nuclear magnetic resonance (NMR) and pyrolysisgas chromatography-mass spectrometry (Py-GC-MS), have provided data on soil chemistry. The combination of these two approaches offers promise in determining soil health status. [Int Microbiol 2005; 8(1):13-21
Performativity, fabrication and trust: exploring computer-mediated moderation
Based on research conducted in an English secondary school, this paper explores computer mediated moderation as a performative tool. The Module Assessment Meeting (MAM) was the moderation approach under investigation. I mobilise ethnographic data generated by a key informant, and triangulated with that from other actors in the setting, in order to examine some of the meanings underpinning moderation within a performative environment. Drawing on the work of Ball (2003), Lyotard (1979) and Foucault (1977, 1979), I argue that in this particular case performativity has become entrenched in teachers’ day-to-day practices, and not only affects those practices but also teachers’ sense of self. I suggest that MAM represented performative and fabricated conditions and (re)defined what the key participant experienced as a vital constituent of her educational identities - trust. From examining the case in point, I hope to have illustrated for those interested in teachers’ work some of the implications of the interface between technology and performativity
Factors Influencing the Concentration of Fecal Coliforms in Oysters in the River Blackwater Estuary, UK
Contamination of water systems can not only entail high risks to human health but can also result in economic losses due to closure of beaches and shellfish harvesting areas. Understanding the origin of fecal pollution at locations where shellfish are grown is essential in assessing associated health risks—as well as the determining actions necessary to remedy the problem. The aim of this work is to identify the species-specific source(s) of fecal contamination impacting waters overlying the shellfisheries in the Blackwater Estuary, East Anglia, UK. Over a twelve-month period, water samples were taken from above the oysters and from a variety of upstream points considered to be likely sources of fecal microorganism, together with oyster samples, and the number of fecal streptococci and E. coli were determined. Transition from low to high tide significantly decreased the concentration of fecal streptococci in waters overlying the oyster beds, indicative of a freshwater input of fecal pollution in oyster bed waters. In 12 months, the number of E. coli remained constant throughout, while fecal streptococci numbers were generally higher in the winter months. Analyses of upstream samples identified a sewage outfall to be the main source of E. coli to the oyster beds, with additional fecal streptococci from agricultural sources. The findings may assist in developing approaches for assessing the risks to shellfishery industries of various fecal inputs into an estuary, which could then help local governmental authorities address the problem
Approaches for advancing scientific understanding of macrosystems
The emergence of macrosystems ecology (MSE), which focuses on regional- to continental-scale ecological patterns and processes, builds upon a history of long-term and broad-scale studies in ecology. Scientists face the difficulty of integrating the many elements that make up macrosystems, which consist of hierarchical processes at interacting spatial and temporal scales. Researchers must also identify the most relevant scales and variables to be considered, the required data resources, and the appropriate study design to provide the proper inferences. The large volumes of multi-thematic data often associated with macrosystem studies typically require validation, standardization, and assimilation. Finally, analytical approaches need to describe how cross-scale and hierarchical dynamics and interactions relate to macroscale phenomena. Here, we elaborate on some key methodological challenges of MSE research and discuss existing and novel approaches to meet them
Neuronal pentraxins mediate synaptic refinement in the developing visual system
Peer reviewedPublisher PD
Case studies and evidence-based approaches to addressing urban soil lead contamination
Urban soils in many communities in the United States and internationally have been contaminated by lead (Pb) from past use of lead additives in gasoline, deterioration of exterior paint, emissions from Pb smelters and battery recycling and other industries. Exposure to Pb in soil and related dust is widespread in many inner city areas. Up to 20–40% of urban children in some neighborhoods have blood lead levels (BLLs) equal to or above 5 μg per decilitre, the reference level of health concern by the U.S. Centers for Disease Control. Given the widespread nature of Pb contamination in urban soils it has proven a challenge to reduce exposure. In order to prevent this exposure, an evidence-based approach is required to isolate or remediate the soils and prevent children and adult's ongoing exposure. To date, the majority of community soil Pb remediation efforts have been focused in mining towns or in discrete neighborhoods where Pb smelters have impacted communities. These efforts have usually entailed very expensive dig and dump soil Pb remediation techniques, funded by the point source polluters. Remediating widespread non-point source urban soil contamination using this approach is neither economical nor feasible from a practical standpoint. Despite the need to remediate/isolate urban soils in inner city areas, no deliberate, large scale, cost effective Pb remediation schemes have been implemented to isolate inner city soils impacted from sources other than mines and smelters. However, a city-wide natural experiment of flooding in New Orleans by Hurricane Katrina demonstrated that declines in soil Pb resulted in major BLL reductions. Also a growing body of literature of smaller scale pilot studies and programs does exist regarding low cost efforts to isolate Pb contaminated urban soils. This paper reviews the literature regarding the effectiveness of soil Pb remediation for reducing Pb exposure and BLL in children, and suggests best practices for addressing the epidemics of low-level Pb poisoning occurring in many inner city areas
Further education sector governors as ethnographers: five case studies
This paper considers how governors in the English Further Education and Skills (FE) sector examined their practice as ethnographers. The paper locates both FE governance and ethnography within the challenges of the performative and Panoptic environments facing English education. In doing so, the paper explores how the informants’ mobilisation of ethnographic methods revealed a novel lens on both governance and the role of ethnographer. Employing Grounded Theory, the paper considers how the participants negotiated philosophical questions regarding evidence, objectivity and truth. The paper suggests that despite the deep-seated complexities inherent in conducting ethnography in performative contexts, the participants generated data which painted a unique and revealing picture upon their practice as governor and researcher
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