71 research outputs found

    Performance of rice under different water regimes and plant nutrient sources

    Get PDF
    Field experiment was carried out at the Soil and Irrigation Research Centre, University of Ghana, Kpong in 2015 and 2016 cropping seasons to evaluate the effect of different soil water condition and plant nutrient sources on the growth and yield of rice. The experiment was laid out in a split plot design with three replications. Water regime and nutrient source were the main and sub-plot factors, respectively. Water regimes included; continuous flooding (CS), alternate wetting and drying (AWD) and moist soil condition between field capacity and permanent wilting point (MC) while the nutrient fertilizer treatments included no fertilizer (N0), 90 kg N/ha mainly from urea fertilizer (N1), 90 kg N/ha from 12.8 tons of compost (N2) and 45 kg N/ha from urea fertilizer + 45 kg N/ha from 6.4 tons of compost (N3). Results from the study revealed that keeping the soil periodically in aerobic and anaerobic condition through AWD method of water management recorded similar growth and grain yield of rice as with complete submergence of paddy field. Combination of inorganic fertilizer and compost for each to supply 45 kg N/ha under AWD produced the highest rice growth and grain yield. There was a positive and significant correlation between grain yield and growth parameters (plant height, chlorophyll content and above ground biomass accumulation).

    Automation of the Freight Wagon Subsystem

    Get PDF
    The wagon as part of the rail freight system is lagging behind other vehicle classes in terms of automation and monitoring. This stems partly not only from a fierce competition with regard to the vehicle cost but also from a long vehicle lifecycle and long innovation cycles. The drawback of the low amount of automation and monitoring of the vehicle is the additional manual labour required for operation and inspection, as well as the many use cases that cannot be served in an optimal fashion. The Wagon 4.0 concept sets out to mitigate these drawbacks by implementing monitoring and automation technologies into the wagon subsystem in an economically feasible manner. Minor extensions to the rail freight systems already lead to major reductions in labour intensity and use cases that can be served in a novel fashion. This chapter introduces the Wagon 4.0 concept and illustrates the benefits based on use cases

    Source-Reconstruction of Event-Related Fields Reveals Hyperfunction and Hypofunction of Cortical Circuits in Antipsychotic-Naive, First-Episode Schizophrenia Patients during Mooney Face Processing

    Get PDF
    Schizophrenia is characterized by dysfunctions in neural circuits that can be investigated with electrophysiological methods, such as EEG and MEG. In the present human study, we examined event-related fields (ERFs), in a sample of medication-naive, first-episode schizophrenia (FE-ScZ) patients (n � 14) and healthy control participants (n � 17) during perception of Mooney faces to investigate the integrity of neuromagnetic responses and their experience-dependent modification. ERF responses were analyzed for M100, M170, and M250components at the sensor and source levels. In addition, we analyzed peak latency and adaptation effects due to stimulus repetition. FE-ScZ patients were characterized by significantly impaired sensory processing, as indicated by a reduced discrimination index (A�). At the sensor level, M100 and M170 responses in FE-ScZ were within the normal range, whereas the M250 response was impaired. However, source localization revealed widespread elevated activity for M100 and M170 in FE-ScZ and delayed peak latencies for the M100 and M250 responses. In addition, M170 source activity in FE-ScZ was not modulated by stimulus repetitions. The present findings suggest that neural circuits in FE-ScZ may be characterized by a disturbed balance between excitation and inhibition that could lead to a failure to gate information flow and abnormal spreading of activity, which is compatible with dysfunctional glutamatergic neurotransmission

    Use of an Electrochemical Split Cell Technique to Evaluate the Influence of Shewanella oneidensis Activities on Corrosion of Carbon Steel

    Get PDF
    Microbially induced corrosion (MIC) is a complex problem that affects various industries. Several techniques have been developed to monitor corrosion and elucidate corrosion mechanisms, including microbiological processes that induce metal deterioration. We used zero resistance ammetry (ZRA) in a split chamber configuration to evaluate the effects of the facultatively anaerobic Fe(III) reducing bacterium Shewanella oneidensis MR-1 on the corrosion of UNS G10180 carbon steel. We show that activities of S. oneidensis inhibit corrosion of steel with which that organism has direct contact. However, when a carbon steel coupon in contact with S. oneidensis was electrically connected to a second coupon that was free of biofilm (in separate chambers of the split chamber assembly), ZRA-based measurements indicated that current moved from the S. oneidensis-containing chamber to the cell-free chamber. This electron transfer enhanced the O2 reduction reaction on the coupon deployed in the cell free chamber, and consequently, enhanced oxidation and corrosion of that electrode. Our results illustrate a novel mechanism for MIC in cases where metal surfaces are heterogeneously covered by biofilms

    Mineralogical and geochemical analysis of Fe-phases in drill-cores from the Triassic Stuttgart Formation at Ketzin COâ‚‚ storage site before COâ‚‚ arrival

    Get PDF
    Reactive iron (Fe) oxides and sheet silicate-bound Fe in reservoir rocks may affect the subsurface storage of CO2 through several processes by changing the capacity to buffer the acidification by CO2 and the permeability of the reservoir rock: (1) the reduction of three-valent Fe in anoxic environments can lead to an increase in pH, (2) under sulphidic conditions, Fe may drive sulphur cycling and lead to the formation of pyrite, and (3) the leaching of Fe from sheet silicates may affect silicate diagenesis. In order to evaluate the importance of Fe-reduction on the CO2 reservoir, we analysed the Fe geochemistry in drill-cores from the Triassic Stuttgart Formation (Schilfsandstein) recovered from the monitoring well at the CO2 test injection site near Ketzin, Germany. The reservoir rock is a porous, poorly to moderately cohesive fluvial sandstone containing up to 2–4 wt% reactive Fe. Based on a sequential extraction, most Fe falls into the dithionite-extractable Fe-fraction and Fe bound to sheet silicates, whereby some Fe in the dithionite-extractable Fe-fraction may have been leached from illite and smectite. Illite and smectite were detected in core samples by X-ray diffraction and confirmed as the main Fe-containing mineral phases by X-ray absorption spectroscopy. Chlorite is also present, but likely does not contribute much to the high amount of Fe in the silicate-bound fraction. The organic carbon content of the reservoir rock is extremely low (<0.3 wt%), thus likely limiting microbial Fe-reduction or sulphate reduction despite relatively high concentrations of reactive Fe-mineral phases in the reservoir rock and sulphate in the reservoir fluid. Both processes could, however, be fuelled by organic matter that is mobilized by the flow of supercritical CO2 or introduced with the drilling fluid. Over long time periods, a potential way of liberating additional reactive Fe could occur through weathering of silicates due to acidification by CO2

    Fear and rumours regarding placental biopsies in a malaria-in-pregnancy trial in Benin.

    Get PDF
    BACKGROUND: A multi-country, community-based trial on scheduled screening and treatment for malaria in pregnancy was conducted in Benin, The Gambia and Burkina Faso. Despite standardized procedures and outcomes, the study became subject to rumours and accusations of placenta being sold for mystical and financial gain by trial staff, leading to drop-out rates of 30% and the consequent halting of placental biopsy sampling in Benin. This paper explores the role of socio-cultural beliefs related to placenta and identified additional factors contributing these rumours. METHODS: A qualitative comparative emergent-theory design was used to assess social factors related to trial implementation and uptake in the three countries. Data from participant observation, informal conversations, group discussions and interviews were triangulated and analysed with NVivo Qualitative Analysis software. RESULTS: Despite similar sociocultural beliefs about the sacred nature of the placenta in all three study countries, these beliefs did not affect participation rates in Burkina Faso and The Gambia and placenta-related rumours only emerged in Benin. Therefore, the presence of beliefs is not a sufficient condition to have generated placenta-selling fears. The rumours in Benin reflected the confluence of placenta-related beliefs and factors related to the implementation of the trial (including a catalysing adverse event and miscommunication during the informed consent procedure). Furthermore, distinct socio-political factors contributed to the emergence of rumours, including the historical distrust in governmental organizations and the tense relationship between some of the actors involved in the trial. CONCLUSION: Transdisciplinary social science research designs should accompany the implementation of the trial. The integration of multiple stakeholders' knowledge and involvement is required to define and solve upcoming barriers
    • …
    corecore