Preliminary Retro-Commissioning Study on Optimal Operation for the Heat Source System of a District Heating Cooling Plant

In order to improve the energy performance of a district heating and cooling (DHC) plant, the expected performance of the plant is studied using simulations based on mathematical models. A complete heat source system model, equipped with an embedded module that automatically determines the on/off states of heat source equipment using cooling/heating loads, has been developed and validated using actual performance measurements. The mean error between the simulated and measured total energy consumption was 4.2%. Using the developed model, three proposals for improving the plant operation are simulated in order to determine how much energy can be saved. The simulation result shows that the three proposals, automating primary water flow rate, fully open bypass valve of heat exchanger during no-ice-thermal-discharge period, and increase chilled water supply temperature to 8°C, could reduce plant total energy consumption by 2.1%, 0.7% and 3.3% respectively

Investigation into Differences in Palatability Among Festulolium Varieties as Haylage

In Japan, paddy fields that are no longer used for cultivation of rice are being converted to cultivation of forage crops. Therefore, grass with greater wet resistance and higher quality is required. Festulolium is an interspecific hybrid between the Lolium and Festuca species and combines the characteristics of high-quality ryegrass and resistance to hostile environments from fescues (Thomas & Humphreys, 1991). Among festulolium varieties, there is wide variation in environmental resistance and feeding value. One festulolium variety, Paulita, shows superior wet resistance to Evergreen and the total digestible nutrients of Evergreen was similar to that of cocksfoot (cv. Kitamidori) (Touno et al., 2004). In this study, we investigated palatability differences in festulolium varieties

Retro-Commissioning and Improvement for District Heating and Cooling System Using Simulation

In order to improve the energy performance of a district heating and cooling (DHC) system, retro-commissioning was analyzed using visualization method and simulation based on mathematical models, and improved operation schemes were proposed according to simulation analysis results. The first part of this paper describes the system performance through visualizing the current operation modes. The second part introduces the retro-commissioning analysis for the system using mathematical models of each component. The third part studies the energy and cost performance of several improved operation proposals using simulation. The results are as follows.1) The carpet plots of current operation modes can be generated automatically and they are useful to check whether the operation is proper or not. 2) The total system simulation model was constructed. The simulation error of the total energy consumption was 1.5% and the percentage of root mean square error (%RMSE) was 16.3%, which show that the simulation is accurate enough to study the performance of proposed operation.3) System simulations for proposed operation schemes were performed. The simulation results show that the system operation with the optimal temperature set point of cooling water at 22oC can improve the total energy coefficient of the heat pump and cooling tower by 2.2 %. Another proposal is that if the return water temperature from users can be kept at the designed value, which is 13±1? compared with the current average value of 10.5?, the total energy consumption can be reduced by 9.5%, and energy cost can be reduced by 11.6%

Cytotoxic Withanolide Constituents of Physalis longifolia

Fourteen new withanolides, 1–14, named withalongolides A–N, respectively, were isolated from the aerial parts of Physalis longifolia together with eight known compounds (15–22). The structures of compounds 1–14 were elucidated through spectroscopic techniques and chemical methods. In addition, the structures of withanolides 1, 2, 3, and 6 were confirmed by X-ray crystallographic analysis. Using a MTS viability assay, eight withanolides (1, 2, 3, 7, 8, 15, 16, and 19) and four acetylated derivatives (1a, 1b, 2a, and 2b) showed potent cytotoxicity against human head and neck squamous cell carcinoma (JMAR and MDA-1986), melanoma (B16F10 and SKMEL-28), and normal fetal fibroblast (MRC-5) cells with IC50 values in the range between 0.067 and 9.3 μM

Field trial on glucose-induced insulin and metabolite responses in Estonian Holstein and Estonian Red dairy cows in two herds

<p>Abstract</p> <p>Background</p> <p>Insulin secretion and tissue sensitivity to insulin is considered to be one of the factors controlling lipid metabolism <it>post partum</it>. The objective of this study was to compare glucose-induced blood insulin and metabolite responses in Estonian Holstein (EH, n = 14) and Estonian Red (ER, n = 14) cows.</p> <p>Methods</p> <p>The study was carried out using the glucose tolerance test (GTT) performed at 31 ± 1.9 days <it>post partum</it> during negative energy balance. Blood samples were obtained at -15, -5, 5, 10, 20, 30, 40, 50 and 60 min relative to infusion of 0.15 g/kg BW glucose and analysed for glucose, insulin, triglycerides (TG), non-esterified fatty acids (NEFA), cholesterol and β-hydroxybutyrate (BHB). Applying the MIXED Procedure with the SAS System the basal concentration of cholesterol, and basal concentration and concentrations at post-infusion time points for other metabolites, area under the curve (AUC) for glucose and insulin, clearance rate (CR) for glucose, and maximum increase from basal concentration for glucose and insulin were compared between breeds.</p> <p>Results</p> <p>There was a breed effect on blood NEFA (<it>P </it>< 0.05) and a time effect on all metabolites concentration (<it>P </it>< 0.01). The following differences were observed in EH compared to ER: lower blood insulin concentration 5 min after glucose infusion (<it>P </it>< 0.05), higher glucose concentration 20 (<it>P </it>< 0.01) and 30 min (<it>P </it>< 0.05) after infusion, and higher NEFA concentration before (<it>P </it>< 0.01) and 5 min after infusion (P < 0.05). Blood TG concentration in ER remained stable, while in EH there was a decrease from the basal level to the 40^thmin nadir (<it>P </it>< 0.01), followed by an increase to the 60^thmin postinfusion (<it>P </it>< 0.01).</p> <p>Conclusion</p> <p>Our results imply that glucose-induced changes in insulin concentration and metabolite responses to insulin differ between EH and ER dairy cows.</p

Role of genetic polymorphisms in tumour angiogenesis

Angiogenesis plays a crucial role in the development, growth and spread of solid tumours. Pro- and anti-angiogenic factors are abnormally expressed in tumours, influencing tumour angiogenesis, growth and progression. Polymorphisms in genes encoding angiogenic factors or their receptors may alter protein expression and/or activity. This article reviews the literature to determine the possible role of angiogenesis-related polymorphisms in cancer. Further research studies in this potentially crucial area of tumour biology are proposed