46 research outputs found

    Аналіз ландшафтного різноманіття Миколаївської області

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    Groundwater systems are increasingly used for seasonal aquifer thermal energy storage (SATES) for periodic heating and cooling of buildings. Its use is hampered in contaminated aquifers because of the potential environmental risks associated with the spreading of contaminated groundwater, but positive side effects, such as enhanced contaminant remediation, might also occur. A first reactive transport study is presented to assess the effect of SATES on the fate of chlorinated solvents by means of scenario modeling, with emphasis on the effects of transient SATES pumping and applicable kinetic degradation regime. Temperature effects on physical, chemical, and biological reactions were excluded as calculations and initial simulations showed that the small temperature range commonly involved (ΔT < 15 °C) only caused minor effects. The results show that a significant decrease of the contaminant mass and (eventually) plume volume occurs when degradation is described as sediment-limited with a constant rate in space and time, provided that dense non-aqueous phase liquid (DNAPL) is absent. However, in the presence of DNAPL dissolution, particularly when the dissolved contaminant reaches SATES wells, a considerably larger contaminant plume is created, depending on the balance between DNAPL dissolution and mass removal by degradation. Under conditions where degradation is contaminant-limited and degradation rates depend on contaminant concentrations in the aquifer, a SATES system does not result in enhanced remediation of a contaminant plume. Although field data are lacking and existing regulatory constraints do not yet permit the application of SATES in contaminated aquifers, reactive transport modeling provides a means of assessing the risks of SATES application in contaminated aquifers. The results from this study are considered to be a first step in identifying the subsurface conditions under which SATES can be applied in a safe or even beneficial manner

    Influence of green tea consumption on endoxifen steady-state concentration in breast cancer patients treated with tamoxifen

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    Background: Many cancer patients use additional herbs or supplements in combination with their anti-cancer therapy. Green tea—active ingredient epigallocatechin-3-gallate (EGCG)—is one of the most commonly used dietary supplements among breast cancer patients. EGCG may alter the metabolism of tamoxifen. Therefore, the aim of this study was to investigate the influence of green tea supplements on the pharmacokinetics of endoxifen; the most relevant active metabolite of tamoxifen. Methods: In this single-center, randomized cross-over trial, effects of green tea capsules on endoxifen levels were evaluated. Patients treated with tamoxifen for at least 3 months were eligible for this study. After inclusion, patients were consecutively treated with tamoxifen monotherapy for 28 days and in combination with green tea supplements (1 g twice daily; containing 300 mg EGCG) for 14 days (or vice versa). Blood samples were collected on the last day of monotherapy or combination therapy. Area under the curve (AUC0–24h), maximum concentration (Cmax) and minimum concentration (Ctrough) were obtained from individual plasma concentration–time curves. Results: No difference was found in geometric mean endoxifen AUC0–24h in the period with green tea versus tamoxifen monotherapy (− 0.4%; 95% CI − 8.6 to 8.5%; p = 0.92). Furthermore, no differences in Cmax (− 2.8%; − 10.6 to 5.6%; p = 0.47) nor Ctrough (1.2%; − 7.3 to 10.5%; p = 0.77) were found. Moreover, no severe toxicity was reported during the whole study period. Conclusions: This study demonstrated the absence of a pharmacokinetic interaction between green tea supplements and tamoxifen. Therefore, the use of green tea by patients with tamoxifen does not have to be discouraged

    Mass transfer processes in crystalline aggregates containing a fluid phase

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    Understanding mass transfer processes in porous crystalline aggregates containing a fluid phase is of major importance for modelling partially molten regions of the Earth's mantle, such as those under mid-ocean spreading ridges. Despite the fact that mid-ocean ridges can be considered the simplest large scale setting where partial melting occurs, many processes at depth beneath the ridges, such as segregation and migration ofthe melt phase, remain poorly understood. For example, essential input information for large scale modelling, such as the melt distribution on the grain scale, whether or not a continuous network of (grain-scale) melt channels exists and the associated transport properties, are poorly constrained. Also poorly constrained is the effect of melt on the rheological behaviour of mantle rock. When trying to combine information from equilibrium (hydrostatic) melt distribution studies and densification or deformation studies on partially molten samples, the difficulty arises that little or no information is available under conditions where both stress-related and surface-energy-related driving forces for grain scale diffusive mass transfer are comparable in magnitude. Such conditions may, however, be important in partially molten regions of the earth. This thesis reports a theoretical and experimental study of grain scale mass transfer processes in solid/fluid systems under the low effective stress conditions where surface energy related forces are expected to become significant

    Commercial Diplomats as corporate entrepreneurs: explaining role behavior from an institutional perspective.

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    This article presents the results of an empirical study on the roles of commercial diplomats at foreign posts. As commercial diplomacy is just starting to grow in importance in a globalising world, the actual work and activities of commercial diplomats at foreign posts have hardly been researched. This is relevant though, since it can help to advance theory that aims to understand commercial diplomacy's effectiveness. A model was developed that conceptualises commercial diplomats' roles as corporate entrepreneurial behaviour, and institutional theory was used to identify the contextual factors that influence their behaviour. By using a multi-method, qualitative and cross-sectional case study based on 23 self-selected, face-to-face, semi-structured interviews, we found that three types of commercial diplomats exist, each adopting a different approach in terms of the importance accredited to proactivity, the level at which it is pursued, and the intensity with which it is pursued. The influence of informal institutions increases for higher levels of proactivity in a specific order, namely background, skills and experience, cultural differences, and the working environment. Further research is needed to confirm these findings

    Commercial Diplomats as corporate entrepreneurs: an institutional perspective

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    This chapter presents a study on the work of commercial diplomats as international business promoters at foreign posts. Research has largely overlooked the actual roles and activities of commercial diplomats in explaining the effectiveness of commercial diplomacy and international business support. In this study, it is assumed that commercial diplomats’ behavior is influenced by informal institutions. Face-to-face semi-structured interviews with 23 commercial diplomats at foreign posts from different countries were conducted and analyzed. The results show three different types of role behavior and differences in proactivity per type. Informal institutions such as background, skills, and experience, cultural differences, and the working environment suggest to explain the differences in levels of proactive international business support behavior of commercial diplomats. Further research is needed to assert these finding

    Biomassa voor de energievoorziening van tuinbouwclusters

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    Biomass combustion in combination with a cluster of greenhouses to provide heat, CO2 and electricity can provide a partly solution to the sustainability of the horticultural sector. A biomass gasification plant could also provide valuable biochar, the result of partial combustion of biocarbon. This was shown to have attractive characteristics to be used in high quality potting soil. Despite the high value of the biochar (contributing for 16% of the income from the plant), the economic feasibility of a biomass combustion plant depends heavily on governmental subsidies (SDE +). When the developed technology is used on a practical scale, a biomass plant of 8 MW thermal power and 1.4 MW of electrical power is a sound size. Such a plant fits well with a horticultural cluster of 15 hectares, consisting of 6 ha Tomato, 6 ha Pepper and 3 hectares of Chrysanthemum. The biomass plant produces over 91% of the heating and 95% of the CO2 requirement and 67% of the electricity counsumed. However during winter a lot of electricity will have to be bought, which is compensated with selling to the public grid in summer. The biomass combustion plant will mainly run on biomass is supplied from elsewhere. The biomass from the local cluster covers only 0.3% of the combusted amount. If all available biomass from Netherlands territory would be used to heat greenhouses about 20% of greenhouse industry could make use of system like described in this report

    Commercial Diplomats as corporate entrepreneurs: an institutional perspective

    No full text
    This chapter presents a study on the work of commercial diplomats as international business promoters at foreign posts. Research has largely overlooked the actual roles and activities of commercial diplomats in explaining the effectiveness of commercial diplomacy and international business support. In this study, it is assumed that commercial diplomats’ behavior is influenced by informal institutions. Face-to-face semi-structured interviews with 23 commercial diplomats at foreign posts from different countries were conducted and analyzed. The results show three different types of role behavior and differences in proactivity per type. Informal institutions such as background, skills, and experience, cultural differences, and the working environment suggest to explain the differences in levels of proactive international business support behavior of commercial diplomats. Further research is needed to assert these finding
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