835 research outputs found

    Impact of fiber source and feed particle size on swine manure properties related to spontaneous foam formation during anaerobic decomposition

    Get PDF
    Foam accumulation in deep-pit manure storage facilities is of concern for swine producers because of the logistical and safety-related problems it creates. A feeding trial was performed to evaluate the impact of feed grind size, fiber source, and manure inoculation on foaming characteristics. Animals were fed: (1) C–SBM (corn–soybean meal): (2) C–DDGS (corn–dried distiller grains with solubles); and (3) C–Soybean Hull (corn–soybean meal with soybean hulls) with each diet ground to either fine (374 μm) or coarse (631 μm) particle size. Two sets of 24 pigs were fed and their manure collected. Factors that decreased feed digestibility (larger grind size and increased fiber content) resulted in increased solids loading to the manure, greater foaming characteristics, more particles in the critical particle size range (2–25 μm), and a greater biological activity/potential

    Development of multi-use platforms at sea:Barriers to realising Blue Growth

    Get PDF
    The recent H2020 Blue Growth projects MARIBE and MUSES investigated the potential of a variety of different combinations of economic activities in co-location or integrated in multi-use platforms. Both projects identified barriers - including regulatory, financing, liability and insurance issues; environmental concerns; stakeholder perceptions; and lack of appropriate skills – that hamper the development of multi-use platforms. The H2020 MARIBE project concluded that further funding for multi-use demonstrations should be provided to increase investor confidence and bring multi-use through the so-called Valley of Death. The H2020 MUSES project concluded that multi-use needs to be proactively facilitated and incentivised through public regulatory bodies and respective support programmes. This paper combines and analyses results from both projects in order to identify key research gaps and actions required for the continued development of multi-use platforms, based on a structured critical review of available peer-reviewed literature on the topic as well as reports of both the MUSES and MARIBE projects. Research gaps and actions are analysed based on a multi-use platform typology to inform developers, policy makers, academia and investors for future development of multi-use at sea

    The Impact of Carbohydrate and Protein Level and Sources on Swine Manure Foaming Properties

    Get PDF
    This study explored the impact of swine diet on the composition, methane production potential, and foaming properties of manure. Samples of swine manure were collected from controlled feeding trials with diets varying in protein and carbohydrate levels and sources. Protein sources consisted of corn with amino acids, corn-soybean meal with amino acids, corn-soybean meal, corn-canola meal, corn-corn gluten meal, and corn-poultry meal. Carbohydrate sources consisted of corn-soybean meal, barley, beet pulp, distillers dried grains with solubles (DDGS), soy hulls, and wheat bran. Manure samples were tested for a number of physical and biochemical parameters, including total solids, volatile solids, viscosity, density, methane production rate, biochemical methane potential, foaming capacity, and foam stability. Statistical analyses were performed to evaluate whether different carbohydrate and/or protein ingredients affected these physico-chemical properties or the samples’ ability to produce methane gas. After conducting these trials, another feeding trial was performed to evaluate if the addition of Narasin into rations (corn-soybean and DDGS) could reduce the methane production rate or potential of the manure. These samples were also tested for the physical and biochemical parameters mentioned previously. Finally, an additional manure foaming study was conducted involving the addition of specific carbohydrates ground to different particle sizes and corn oil to observe the effects that the additives had on foaming capacity and stability

    Three-Phase Foam Analysis and the Development of a Lab-Scale Foaming Capacity and Stability Test for Swine Manures

    Get PDF
    Foam accumulation on the manure slurry at deep pit swine facilities has been linked to flash fire incidents, making it a serious safety concern for pork producers. In order to investigate this phenomenon, samples of swine manure were collected from over 50 swine production facilities in Iowa with varying levels of foam accumulation over a seven month period. These samples were tested for a number of physical and chemical parameters including temperature, pH, total solids, volatile solids, volatile fatty acid concentration, biochemical methane potential, and methane production rate. After establishing these parameters, a foaming capacity and stability test was performed where samples were placed in clear PVC tubes with air diffusers at the bottom to simulate biogas production. The amount of foam produced at a set aeration rate was recorded as a measure of foaming capacity, and foam stability was assessed by measuring the height of foam remaining at certain time intervals after aeration had ceased. The results of this test indicated that samples collected from foaming barns showed a greater capacity to produce and stabilize foam. In addition, statistical analysis indicated that manures with foam produced methane at significantly greater rates than non-foaming manures (0.154 ± 0.010 and 0.052 ± 0.003 L CH4./L slurry*day respectively, average standard error), and consequently had significantly greater fluxes of methane moving through the manure volume. On the other hand, the biochemical methane production assay suggested that manure from foaming pits had less potential to generate methane (112 ± 9 mL CH4/g VS) than non-foaming pits (129 ± 9 mL CH4/g VS), and the VFA analysis showed significantly lower concentrations in foaming pits (4472, 3486, and 1439 μg/g for the surface level and descending depths of the pit, respectively) as compared to non-foaming pits (9385,8931, and 6938 μg/g for the same sample depths). When taken together, these assays suggest enhanced anaerobic digestion efficiency from foaming barns, as well as the possible accumulation of a surfactant at the manure-air interface of foaming deep pits. Overall, this work supports a three-phase system conceptualization of foam production in swine manure deep pits, and that the control of one or more of these phases will be required for mitigation

    Influence of lithium in neuron-glia interaction in hippocampal neurons: preliminary study

    Get PDF
    Recentemente, especial atenção foi dada aos possíveis efeitos neuroprotetores do lítio, especialmente pela descoberta de seus efeitos regulatórios sobre proteínas pró e anti-apoptóticas. O lítio aumenta substancialmente a expressão de proteínas citoprotetoras no sistema nervoso central, tanto no córtex de ratos quanto em células humanas de origem neuronal. Além de ações neuroprotetoras, auxilia na regeneração de axônios no sistema nervoso central de mamíferos. O lítio regula negativamente a expressão e a atividade de enzimas que exercem funções importantes na homeostase cerebral: plasticidade sináptica, neurogênese e fosforilação da proteína tau. Microglia é conhecida por sua importância na neuropatologia. No entanto, sob condições fisiológicas, tais células imunes interagem ativamente com os neurônios, sendo capazes de modular o destino e as funções das sinapses. Essa capacidade das células microgliais sugere as conseqüências de mudanças no fenótipo microglial sob condições patológicas, o que torna relevante o entendimento da interação entre micróglia e outras células cerebrais em desenvolvimento e sua influência na formação de redes neuronais e sinápticas. O presente trabalho tem como objetivo identificar a principal via de integração neurônio-glia ativada pelo tratamento crônico com lítio em neurônios, explorando o uso de ferramentas de bioinformática em dados de microarray. O tratamento de neurônios hipocampais com lítio alterou os genes relacionados a diferentes vias de neuroproteção na dose terapêutica mais alta. Houve dissociação entre a dose terapêutica e sub-terapêutica de lítio na neuroproteção. Portanto, o tratamento em doses terapêuticas (2mM) modificou diferentes vias de sinalização quando comparado com as doses sub-terapêuticas (0,02 e 0,2mM).Recently, special attention has been given to the possible neuroprotective effects of lithium, especially by the discovery of its regulatory effects on pro and anti-apoptotic proteins. Lithium substantially increases the cytoprotective proteins expression in the central nervous system, both in rat cortex and in human cells of neuronal origin. In addition to neuroprotective actions, it aids in the regeneration of axons in the central nervous system of mammals. Lithium negatively regulates the expression and activity of enzymes that exert important functions in cerebral homeostasis: synaptic plasticity, neurogenesis, and phosphorylation of tau protein. Microglia is known for its importance in neuropathology. However, under physiological conditions, such immune cells interact actively with neurons, being able to modulate the fate and functions of the synapses. Such ability of microglial cells suggests the consequences of changes in microglial phenotype under pathological conditions, which makes it relevant to understand the interaction between microglial and other developing brain cells and their influence on the formation of neuronal and synaptic networks. The current work aims to identify the main pathway of neuronal-glia integration activated by chronic treatment with lithium in neurons, exploring the use of bioinformatics tools in microarray data. Treatment of primary hippocampal neurons with lithium changed the genes related to different neuroprotection pathways at the highest therapeutic dose. There was dissociation between the therapeutic and sub-therapeutic dose of lithium in neuroprotection. Therefore, treatment at therapeutic doses (2mM) modified different signaling pathways when compared to the sub-therapeutic dose (0.02 and 0.2mM)

    Aboriginal Status is a Prognostic Factor for Mortality among Antiretroviral Naive HIV-Positive Individuals First Initiating HAART

    Get PDF
    Background: Although the impact of Aboriginal status on HIV incidence, HIV disease progression, and accessto treatment has been investigated previously, little is known about the relationship between Aboriginal ethnicityand outcomes associated with highly active antiretroviral therapy (HAART). We undertook the present analysisto determine if Aboriginal and non-Aboriginal persons respond differently to HAART by measuring HIV plasmaviral load response, CD4 cell response and time to all-cause mortality.Methods: A population-based analysis of a cohort of antiretroviral therapy naïve HIV-positive Aboriginal menand women 18 years or older in British Columbia, Canada. Participants were antiretroviral therapy naïve, initiatedtriple combination therapy between August 1, 1996 and September 30, 1999. Participants had to complete abaseline questionnaire as well as have at least two follow-up CD4 and HIV plasma viral load measures. Theprimary endpoints were CD4 and HIV plasma viral load response and all cause mortality. Cox proportionalhazards models were used to determine the association between Aboriginal status and CD4 cell response, HIVplasma viral load response and all-cause mortality while controlling for several confounder variables.Results: A total of 622 participants met the study criteria. Aboriginal status was significantly associated with noAIDS diagnosis at baseline (p = 0.0296), having protease inhibitor in the first therapy (p = 0.0209), lower baselineHIV plasma viral load (p < 0.001), less experienced HIV physicians (P = 0.0133), history of IDU (p < 0.001), notcompleting high school (p = 0.0046), and an income of less than $10,000 per year (p = 0.0115). Cox proportionalhazards models controlling for clinical characteristics found that Aboriginal status had an increased hazard ofmortality (HR = 3.12, 95% CI: 1.77–5.48) but did not with HIV plasma viral load response (HR = 1.15, 95% CI:0.89–1.48) or CD4 cell response (HR = 0.95, 95% CI: 0.73–1.23).Conclusion: Our study demonstrates that HIV-infected Aboriginal persons accessing HAART had similar HIVtreatment response as non-Aboriginal persons but have a shorter survival. This study highlights the need forcontinued research on medical interventions and behavioural changes among HIV-infected Aboriginal and othermarginalized populations

    Distinctive effects of eicosapentaenoic and docosahexaenoic acids in regulating neural stem cell fate are mediated via endocannabinoid signalling pathways

    Get PDF
    Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1β deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1β signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1β deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair
    corecore