1,854 research outputs found
Can on-farm bioenergy production make organic farming more sustainable? - A model for energy balance, nitrogen losses, and green house gas emissions in a 1000 ha energy catchment with organic dairy farming and integrated bioenergy production
Can biogas and bioethanol production make organic farming more sustainable?
- Results from a model for the fossil energy balance, Nitrogen losses, and greenhouse gas emissions in a 1000 ha energy catchment with organic dairy farming and integrated biogas and bioethanol production.
Dalgaard T1, Pugesgaard S1, Jørgensen U1, Olesen JE1, Møller HB1 and Jensen ES2
1) Dept. Agroecology and Environment. Faculty of Agricultural Sciences (DJF), University of Aarhus. DK-8830 Tjele. Denmark. Contact: [email protected]
2) Biosystems Department, Risø DTU, The National Laboratory for Sustainable Energy, The Technical University of Denmark DK-4000 Roskilde, Denmark
The vision of organic farming systems, independent of fossil energy resources, with significantly lower nutrient losses, and no net contribution to the greenhouse gas emissions might be fulfilled via the integration of biogas production. This is an important hypothesis investigated in the www.bioconcens.elr.dk/uk/ research project.
This poster illustrates preliminary results from a model for the fossil energy balance, Nitrogen losses, and greenhouse gas emissions in a 1000 ha energy catchment with organic dairy farming and integrated biogas production in Denmark. The model will draw on results from previous models (e.g the farmGHG model), and includes a number of organic dairy farm type components, including information on livestock production, housing, manure storage, manure and fodder import/export, crop rotations, yield levels, and soil types. In addition, a biogas plant model component evaluates effects of the inclusion of variable amounts of manures and crop residues from the specified farm types, into the biogas energy production.
The model is intended to result in an overall catchment balance for the following three types of indicators: 1) the fossil energy use – i.e. the net fossil energy use minus the bioenergy production, 2) losses of Nitrogen in the form of nitrates, ammonia and nitrous oxide, and 3) the emission of the three main greenhouse gasses from agriculture: carbon dioxide, nitrous oxide and methane, measured in carbon dioxide equivalents. Moreover, these indicator values are specified for each of the farm types included in the model, and for the biogas plant component. Finally, selected model results are discussed in relation to the overall hypothesis of the research project, and it is discussed how the integration of biogas production in organic farming, can help to improve the self-sufficiency in Nitrogen, and thereby reduce the import of nutrients to the organic farming systems
Bipolar querying of valid-time intervals subject to uncertainty
Databases model parts of reality by containing data representing properties of real-world objects or concepts. Often, some of these properties are time-related. Thus, databases often contain data representing time-related information. However, as they may be produced by humans, such data or information may contain imperfections like uncertainties. An important purpose of databases is to allow their data to be queried, to allow access to the information these data represent. Users may do this using queries, in which they describe their preferences concerning the data they are (not) interested in. Because users may have both positive and negative such preferences, they may want to query databases in a bipolar way. Such preferences may also have a temporal nature, but, traditionally, temporal query conditions are handled specifically. In this paper, a novel technique is presented to query a valid-time relation containing uncertain valid-time data in a bipolar way, which allows the query to have a single bipolar temporal query condition
BioConcens: Biomass and bioenergy production agriculture – consequences for soil fertility, environment, spread of animal parasites and socio-economy
The research programme called “international research cooperation and organic integrity” was commenced for a period 2006-2010. It is coordinated by DARCOF (The Danish Research Centre for Organic Farming). The whole programme, with acronym DARCOF III, consists of 15 projects (http://www.darcof.dk/research/darcofiii/index.html). One of them is BIOCONCENS - Biomass and bioenergy production in organic farming – consequences for soil fertility, environment, spread of animal parasites and socio-economy (http://www.bioconcens.elr.dk/uk/). The production of bioenergy in organic agriculture (OA) can reduce its dependency of fossil fuels and decrease green house gasses emission; consequently it will increase sustainability of organic farms. Biorefinery concept based on co-production of biogas, bioethanol and protein fodder in organic farming will be developed within the BIOCONCENS project and the background for the project and the different work packages will be presented in this paper
Two-body correlations in Bose condensates
We formulate a method to study two-body correlations in a condensate of N
identical bosons. We use the adiabatic hyperspheric approach and assume a
Faddeev like decomposition of the wave function. We derive for a fixed
hyperradius an integro-differential equation for the angular eigenvalue and
wave function. We discuss properties of the solutions and illustrate with
numerical results. The interaction energy is for N~20 five times smaller than
that of the Gross-Pitaevskii equation
Improved Beamforming for Lateral Oscillations in Elastography Using Synthetic Aperture Imaging
International audienc
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Nursing teamwork in the care of older people: A mixed methods study
Healthcare is increasingly complex and requires the ability to adapt to changing demands. Teamwork is essential
to delivering high quality care and is central to nursing. The aims of this study were to identify the processes that
underpin nursing teamwork and how these affect the care of older people, identify the relationship between
perceived teamwork and perceived quality of care, and explore in depth the experience of working in nursing
teams. The study was carried out in three older people's wards in a London teaching hospital. Nurses and
healthcare assistants completed questionnaires (n=65) on known dynamics of teamwork (using the Nursing
Teamwork Survey) together with ratings of organisational quality (using an adapted AHRQ HSPS scale). A
sample (n=22; 34%) was then interviewed about their perceptions of care, teamwork and how good outcomes
are delivered in everyday work. Results showed that many care difficulties were routinely encountered, and
confirmed the importance of teamwork (e.g. shared mental models of tasks and team roles and responsibilities,
supported by leadership) in adapting to challenges. Perceived quality of teamwork was positively related to
perceived quality of care. Work system variability and the external environment influenced teamwork, and
confirmed the importance of team adaptive capacity. The CARE model shows the centrality of teamwork in
adapting to variable demand and capacity to deliver care processes, and the influence of broader system factors
on teamworking
Program Components and Results From an Organized Colorectal Cancer Screening Program Using Annual Fecal Immunochemical Testing.
Programmatic colorectal cancer (CRC) screening increases uptake, but the design and resources utilized for such models are not well known. We characterized program components and participation at each step in a large program that used mailed fecal immunochemical testing (FIT) with opportunistic colonoscopy.
Mixed-methods with site visits and retrospective cohort analysis of 51-75-year-old adults during 2017 in the Kaiser Permanente Northern California integrated health system.
Among 1,023,415 screening-eligible individuals, 405,963 (40%) were up to date with screening at baseline, and 507,401 of the 617,452 not up-to-date were mailed a FIT kit. Of the entire cohort (n = 1,023,415), 206,481 (20%) completed FIT within 28 days of mailing, another 61,644 (6%) after a robocall at week 4, and 40,438 others (4%) after a mailed reminder letter at week 6. There were over 800,000 medical record screening alerts generated and about 295,000 FIT kits distributed during patient office visits. About 100,000 FIT kits were ordered during direct-to-patient calls by medical assistants and 111,377 people (11%) completed FIT outside of the automated outreach period. Another 13,560 (1.3%) completed a colonoscopy, sigmoidoscopy, or fecal occult blood test unrelated to FIT. Cumulatively, 839,463 (82%) of those eligible were up to date with screening at the end of the year and 12,091 of 14,450 patients (83.7%) with positive FIT had diagnostic colonoscopy.
The >82% screening participation achieved in this program resulted from a combination of prior endoscopy (40%), large initial response to mailed FIT kits (20%), followed by smaller responses to automated reminders (10%) and personal contact (12%)
Biomass and bioenergy production in organic agriculture. Consequences for soil fertility, environment, spread of animal parasites and socio-economy. BioConcnes, a 4-year interdisciplinary project.
Energy production and energy use in organic agriculture (OA) need to be addressed in order to reduce the reliance on non-renewable fossil fuels and minimize greenhouse gas (GHG) emissions. Thus, there is an obligation to find consensus between the apparent opposing aims of renewable (bio) energy production and soil fertility in OA. This project aims at designing and evaluate a combined concept for biomass and bio-energy production in OA, while considering soil fertility
Afrika – Fremtidens Økologiske Kontinent?
Afrikanske bønders forbrug af fossil energi er lavt – og deres forurening med nitrat, sprøjtegifte og klimagasser er begrænset
Spatial representation of temporal information through spike timing dependent plasticity
We suggest a mechanism based on spike time dependent plasticity (STDP) of
synapses to store, retrieve and predict temporal sequences. The mechanism is
demonstrated in a model system of simplified integrate-and-fire type neurons
densely connected by STDP synapses. All synapses are modified according to the
so-called normal STDP rule observed in various real biological synapses. After
conditioning through repeated input of a limited number of of temporal
sequences the system is able to complete the temporal sequence upon receiving
the input of a fraction of them. This is an example of effective unsupervised
learning in an biologically realistic system. We investigate the dependence of
learning success on entrainment time, system size and presence of noise.
Possible applications include learning of motor sequences, recognition and
prediction of temporal sensory information in the visual as well as the
auditory system and late processing in the olfactory system of insects.Comment: 13 pages, 14 figures, completely revised and augmented versio
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