129 research outputs found

    Biogas production by co-ensiling catch crops and straw, effect of substrate blend and microbial communities

    Get PDF
    The combination of catch crop (CC) and barley straw(S) for biogas production was investigated in order to evaluate the ensiling process in batch assay and in continuous process. Based on two new agriculture strategies designed to produce energy and improve nutrient cycling in organic farming are being evaluated, one of them consisting on the harvest of straw and catch crop in different periods whereas the other strategy consists on harvesting them at the same time. Catch crops is promoted to reduce nutrient leaching during rainy season and straw that is not used for animal feeding or bedding is generally left in the field. Mixtures of CC and S provides several advantages: 1) Provides adequate TS for silage, 2) Absorbs the silage effluent, 3) Produces high LAB activity, and 4) Provides an optimal C/N for anaerobic digestion (AD). The effect of feeding compositions (straw or manurea ddition) on the microbial community structures were also investigated

    Effect of anaerobic digestion of cover crops and straw on N and S availability in the digestate

    Get PDF
    Lack of nutrients and poor synchrony between nutrient availability and crop demand are often reasons for low yields in organic farming. A field experiment conducted in Denmark aims to use cover crops (CC) to produce extra biomass for biogas production and afterwards utilize the digestate as nitrogen (N) and sulfur (S) fertilizer. The influence of the main crop harvest time and the straw management on biomass production of cover crops is investigated. A spring barley crop and an under-sown CC (clover and chicory mixture) were established to compare early and late barley harvest time and different straw management, including a treatment with high stubble. The dry matter (DM) yield of CC in October was 2.5 t/ha for early barley harvest and 2.3 t/ha for late harvest. At early barley harvest with high stubble treatment, an extra DM yield of 1.3 t/ha was obtained. The harvested CC was ensiled and used as substrates for mono- and co-digestion with cattle manure in 15L digesters. The silages contained mixtures of CC and straw at ratios 1:0, 3:1 and 10:1 (fresh weight basis). Anaerobic digestion (AD) increased the fraction of NH4+ in total N from 0.07 to 0.41 in a reactor fed with CC silage only, for example. This increase was lower for reactors fed with higher ratio of straw in the silage mixture. In 2018, the N fertilizer value of cattle manure and different digestates and raw silages are tested in a new spring barley crop in confined microplots. Yields and N uptake of spring barley will be measured and the fertilizer value of digested materials will be compared with corresponding undigested cover crops. In addition, the fate of N and S in the soil with different cover crop-straw mixtures and digestion management will be investigated

    Digestates from cover crop, straw and cattle slurry mixtures as nutrient source in organic cropping system

    Get PDF
    Yields in organic arable farming are way below the potential. The reasons are due to the lack of nutrients and poor synchrony between nutrient availability and crop demand (Möller and Müller, 2012). Nitrogen (N) is often the most limiting nutrient for biomass production. Nitrogen available in soil is taken up by plant almost exclusively in mineral form. Yet, limitation of mineralized N in soil is often the problem especially in organic farming. In crop management systems using only organic substrates, the challenge is to increase the N mineral fertilizer value of organic substrates in order for organic farming to rely on organic fertilizer sources. Anaerobic digestion has the potential to increase the nutrients availability (Webb et al., 2013). Cover crops (CC) are useful to reduce nutrient leaching losses and they have the potential to produce extra biomass for biogas production. If a CC with symbiotic N fixation is used the CC can also contribute with extra N to the system. The biomass production in cover crops is influenced by the main crop harvest time and probably by the straw management. The aim of the current study is to quantify the influence of main crop harvest time and straw management and the inclusion of anaerobic digestion of cover crops and straw on N utilization and on potential biogas production. A comparison between mono- and co-digestion of cover crops, straw and cattle slurry is also included

    A qualitative study of the learning processes in young physicians treating suicidal patients: from insecurity to personal pattern knowledge and self-confidence

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Little empirical work has been done in studying learning processes among newly educated physicians in the mental health field.</p> <p>The aim of the study was to shed light on the meaning of newly educated physicians' lived experiences of learning processes related to treating suicidal patients.</p> <p>Methods</p> <p>Thirteen newly educated physicians narrated their learning experiences while treating suicidal patients in their own practice. The interview texts were transcribed and interpreted using a phenomenological-hermeneutical method inspired by Ricoeur's philosophy.</p> <p>Results</p> <p>There was one main theme, four themes and eleven sub themes. The main theme was: Being in a transitional learning process. The themes and sub themes were: Preparing for practice (Getting tools and training skills, Becoming aware of one's own attitudes); Gaining experience from treating patients (Treating and following up patients over time, Storing memories and recognizing similarities and differences in patients); Participating in the professional community (Being an apprentice, Relating clinical stories and receiving feedback, Sharing emotions from clinical experiences, Receiving support from peers); and Developing personal competence (Having unarticulated awareness, Having emotional knowledge, Achieving self-confidence). The informants gave a detailed account of the learning process; from recognising similarities and differences in patients they have treated, to accumulating pattern knowledge, which then contributed to their personal feelings of competence and confidence. They described their personal competence with cognitive and emotional elements consisting of both articulated and less articulated knowledge. The findings are interpreted in relation to different learning theories that focus on both individual factors and the interaction with the learning environment.</p> <p>Conclusion</p> <p>This study provides additional information about learning experiences of young physicians during the critical transition phase from medical school to early professional life. Peers are used for both learning and support and might represent a more powerful resource in the learning process than previously recognized. Emotional experiences do not seem to be adequately focused upon in supervision, which obviously has relevance both for learning and for the well-being of young professionals. The study indicates some areas of the educational system that could profitably be expanded including stimulating more systematically to critical reflection on and in practice, attention to feelings in the reflective process and provision of more performance feedback to young physicians.</p

    Особливості формування самостійної пізнавальної діяльності майбутніх учителів математики

    Get PDF
    (uk) У статті зроблено спробу розкрити особливості самостійної пізнавальної діяльності майбутніх вчителів; досліджуються різні підходи до цього поняття; розкриваються такі його складові, як самостійність, пізнавальна самостійність, пізнавальна діяльність.(ru) В статье сделана попытка раскрыть особенности самостоятельной познавательной деятельности будущих учителей; исследуются различные подходы к этому понятию; раскрываются такие его составляющие, как самостоятельность, познавательная самостоятельность, познавательная деятельность

    A Combined CXCL10, CXCL8 and H-FABP Panel for the Staging of Human African Trypanosomiasis Patients

    Get PDF
    The actual serological and parasitological tests used for the diagnosis of human African trypanosomiasis (HAT), also known as sleeping sickness, are not sensitive and specific enough. The card agglutination test for trypanosomiasis (CATT) assay, widely used for the diagnosis, is restricted to the gambiense form of the disease, and parasitological detection in the blood and cerebrospinal fluid (CSF) is often very difficult. Another very important problem is the difficulty of staging the disease, a crucial step in the decision of the treatment to be given. While eflornithine is difficult to administer, melarsoprol is highly toxic with incidences of reactive encephalopathy as high as 20%. Staging, which could be diagnosed as early (stage 1) or late (stage 2), relies on the examination of CSF for the presence of parasite and/or white blood cell (WBC) counting. However, the parasite is rarely found in CSF and WBC count is not standardised (cutoff set between 5 and 20 WBC per µL). In the present study, we hypothesized that an early detection of stage 2 patients with one or several proteins in association with clinical evaluation and WBC count would improve staging accuracy and allow more appropriate therapeutic interventions

    Unexpected High Digestion Rate of Cooked Starch by the Ct-Maltase-Glucoamylase Small Intestine Mucosal α-Glucosidase Subunit

    Get PDF
    For starch digestion to glucose, two luminal α-amylases and four gut mucosal α-glucosidase subunits are employed. The aim of this research was to investigate, for the first time, direct digestion capability of individual mucosal α-glucosidases on cooked (gelatinized) starch. Gelatinized normal maize starch was digested with N- and C-terminal subunits of recombinant mammalian maltase-glucoamylase (MGAM) and sucrase-isomaltase (SI) of varying amounts and digestion periods. Without the aid of α-amylase, Ct-MGAM demonstrated an unexpected rapid and high digestion degree near 80%, while other subunits showed 20 to 30% digestion. These findings suggest that Ct-MGAM assists α-amylase in digesting starch molecules and potentially may compensate for developmental or pathological amylase deficiencies

    Alterations in osteoclast function and phenotype induced by different inhibitors of bone resorption - implications for osteoclast quality

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Normal osteoclasts resorb bone by secretion of acid and proteases. Recent studies of patients with loss of function mutations affecting either of these processes have indicated a divergence in osteoclastic phenotypes. These difference in osteoclast phenotypes may directly or indirectly have secondary effects on bone remodeling, a process which is of importance for the pathogenesis of both osteoporosis and osteoarthritis. We treated human osteoclasts with different inhibitors and characterized their resulting function.</p> <p>Methods</p> <p>Human CD14 + monocytes were differentiated into mature osteoclasts using RANKL and M-CSF. The osteoclasts were cultured on bone in the presence or absence of various inhibitors: Inhibitors of acidification (bafilomycin A1, diphyllin, ethoxyzolamide), inhibitors of proteolysis (E64, GM6001), or a bisphosphonate (ibandronate). Osteoclast numbers and bone resorption were monitored by measurements of TRACP activity, the release of calcium, CTX-I and ICTP, as well as by counting resorption pits.</p> <p>Results</p> <p>All inhibitors of acidification were equally potent with respect to inhibition of both organic and inorganic resorption. In contrast, inhibition of proteolysis by E64 potently reduced organic resorption, but only modestly suppressed inorganic resorption. GM6001 alone did not greatly affect bone resorption. However, when GM6001 and E64 were combined, a complete abrogation of organic bone resorption was observed, without a great effect on inorganic resorption. Ibandronate abrogated both organic and inorganic resorption at all concentrations tested [0.3-100 μM], however, this treatment dramatically reduced TRACP activity.</p> <p>Conclusions</p> <p>We present evidence highlighting important differences with respect to osteoclast function, when comparing the different types of osteoclast inhibitors. Each class of osteoclast inhibitors will lead to different alterations in osteoclast quality, which secondarily may lead to different bone qualities.</p

    Socially and biologically inspired computing for self-organizing communications networks

    Get PDF
    The design and development of future communications networks call for a careful examination of biological and social systems. New technological developments like self-driving cars, wireless sensor networks, drones swarm, Internet of Things, Big Data, and Blockchain are promoting an integration process that will bring together all those technologies in a large-scale heterogeneous network. Most of the challenges related to these new developments cannot be faced using traditional approaches, and require to explore novel paradigms for building computational mechanisms that allow us to deal with the emergent complexity of these new applications. In this article, we show that it is possible to use biologically and socially inspired computing for designing and implementing self-organizing communication systems. We argue that an abstract analysis of biological and social phenomena can be made to develop computational models that provide a suitable conceptual framework for building new networking technologies: biologically inspired computing for achieving efficient and scalable networking under uncertain environments; socially inspired computing for increasing the capacity of a system for solving problems through collective actions. We aim to enhance the state-of-the-art of these approaches and encourage other researchers to use these models in their future work

    Hierarchical Models in the Brain

    Get PDF
    This paper describes a general model that subsumes many parametric models for continuous data. The model comprises hidden layers of state-space or dynamic causal models, arranged so that the output of one provides input to another. The ensuing hierarchy furnishes a model for many types of data, of arbitrary complexity. Special cases range from the general linear model for static data to generalised convolution models, with system noise, for nonlinear time-series analysis. Crucially, all of these models can be inverted using exactly the same scheme, namely, dynamic expectation maximization. This means that a single model and optimisation scheme can be used to invert a wide range of models. We present the model and a brief review of its inversion to disclose the relationships among, apparently, diverse generative models of empirical data. We then show that this inversion can be formulated as a simple neural network and may provide a useful metaphor for inference and learning in the brain
    corecore