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81.
Coton E Coton M Levert D Casaregola S Sohier D 《International journal of food microbiology》2006,108(1):130-135
In this study, rDNA ITS restriction analysis was used to identify yeasts from two naturally fermented products: French ciders and black olives. In cider musts and bottled ciders, the PCR-RFLP method generated 15 different ITS/RFLP profiles for a total of 208 isolates. The predominant yeasts corresponded to Saccharomyces bayanus, Saccharomyces cerevisiae, Lachancea cidri and Dekkera anomala. Three identified species: Candida sake, Candida tropicalis and Kluyveromyces marxianus had never been described before in ciders. For the black olive fermentation, the method allowed for identification of 11 profiles for a total of 137 isolates. A sequential apparition of yeasts was observed with Pichia anomala, Candida boidinii and Debaryomyces etchellsii being the predominant species. Four isolates did not correspond to any known species based on the sequencing of the D1/D2 region of the 26S rRNA gene. By using the rDNA ITS method, valuable information on yeast population biodiversity and dynamics in the naturally fermented food products studied was obtained. 相似文献
82.
Jafari A Emmanuel DG Christopherson RJ Thompson JR Murdoch GK Woodward J Field CJ Ametaj BN 《Journal of dairy science》2006,89(12):4660-4668
The objective of this study was to investigate whether administration of l-Gln would affect mediators of acute phase response in postparturient dairy cows. Twenty-four multiparous Holstein cows were blocked by the expected day of calving and randomly assigned to 1 of the 3 treatment groups (n = 8/group): 1) i.v. infusion of 10 L of 0.85% NaCl (control), 2) i.v. infusion of 106, or 3) 212 g/d of l-Gln mixed with 10 L of 0.85% NaCl solution; each treatment was given 8 h/d for each of 7 consecutive days starting on d 1 after calving. Blood samples were collected 1 wk before the expected day of parturition as well as on d 0, 7, 14, and 21 after parturition; plasma concentrations of serum amyloid A (SAA), haptoglobin, and lipopolysaccharide-binding protein were measured by ELISA, and α1-acid glycoprotein was assessed by radial immunodiffusion. Concentrations of SAA, haptoglobin, and α1-acid glycoprotein increased in control cows after parturition, reaching peak values on d 0 or 7 postpartum (60, 1,093, and 963 μg/mL, respectively). Cows infused with 106 g/d of l-Gln had greater concentrations of SAA in plasma on d 14 and 21 compared with controls (62.8 vs. 30.2 and 71.1 vs. 34.5 μg/mL, respectively). Cows infused with 212 g/d of l-Gln had greater concentrations of SAA on d 7 (82.5 vs. 53.9 μg/mL) and lower concentrations of haptoglobin on d 14 and 21 postpartum compared with controls (264 vs. 621 and 175 vs. 587 μg/mL, respectively). Cows treated with 106 and 212 g/d of l-Gln had greater plasma lipopolysaccharide-binding protein concentrations on d 7 compared with control group (50.0 and 35.6 vs. 10.8 μg/mL, respectively). There were no treatment differences with respect to milk yield and DM intake during the experimental period. In conclusion, our data indicate that i.v. administration of l-Gln modulated acute phase mediators in dairy cows after parturition and warrants further research into the mechanisms behind these effects. 相似文献
83.
Emmanuel T. D. Mensah Hederick R. Dankwa Torben L. Lauridsen Dennis Trolle Ruby Asmah Benjamin B. Campion Regina Edziyie Villy Christensen 《Lakes & Reservoirs: Research and Management》2019,24(3):246-254
A mass balance model of trophic interactions among ten key functional producer and consumer groups in Lake Volta was constructed using the Ecopath model to study the energy flows and species interactions in the lake. The present study was based on secondary and primary data on fish catch, diet composition, phytoplankton and zooplankton biomasses, collected in 2015 and 2016. Additional information on growth parameters of major species required for balancing the Ecopath model was obtained from sampling and FishBase. The functional groups were detritus, phytoplankton, zooplankton, benthos, prey fish, Tilapia, Bagrus, Chrysichthys, Alestes and Synodontis species. Four trophic levels were identified in the Lake Volta ecosystem, with the energy flow occurring mainly within the first three trophic levels. The calculated ecotrophic efficiency value of the primary producers (phytoplankton: 0.17; detritus: 0.22) indicated they were least exploited, compared to the secondary producers, zooplankton (0.80) and benthos (0.50). All secondary consumers had ecotrophic efficiency values higher than the primary producers, indicating they are exploited in the ecosystem. The main energy flows in the lake were from phytoplankton and detritus at trophic level I, and Bagrus species, the top predator, at a level of 3.30. The network analysis, illustrating a connectance index of 0.43 and an omnivory index of 0.06, in the lake system indicated the ecosystem is unstable, somewhat immature and still in a developing stage. 相似文献
84.
Xin-Yu Wan Ping-An Zhong Emmanuel Kwame Appiah-Adjei 《Water Resources Management》2014,28(10):2833-2849
Optimal water allocation is an important means of improving water use efficiency. However, since water allocation options are usually characterized by multi-region, multi-principle and multi-criterion factors, decision-makers often have difficulty in making objective decisions using them because the many available water allocation options often make the ratings of the options so close to be ranked. This study present a hierarchy variable sets (VS) model, based on the single-layer variable sets model, for ranking the water allocation options of Jining City, China. The ratings of the options are evaluated using a fuzzy rating interval (FRI) that can overcome homogenization in the ratings. The structure of the model presented in this study is clear with a simple procedure of computation and the result is rational. The case study used illustrates that this model can help decision-makers know the rating of water allocation options partially and overall. The computed result from this model appears more convincing than a previous water allocation approach for the city based on the maximum entropy principle. 相似文献
85.
86.
This paper tries to assess the relationship between disaggregate energy consumption and industrial output in South Africa by undertaking a cointegration analysis using annual data from 1980 to 2005. We also investigate the causal relationships between the various disaggregate forms of energy consumption and industrial production. Our results imply that industrial production and employment are long-run forcing variables for electricity consumption. Applying the [Toda, H.Y., Yamamoto, T., 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal of Econometrics 66, 225–250] technique to Granger-causality, we find bi-directional causality between oil consumption and industrial production. For the other forms of energy consumption, there is evidence in support of the energy neutrality hypothesis. There is also evidence of causality between employment and electricity consumption as well as coal consumption causing employment. 相似文献
87.
Mechanical systems often use springs to store energy though their axial length must sometimes be significantly reduced. This
leads to the use of conical springs as they are able to telescope. Designers of mechanical systems can call on a large number
of tools to assist them though most of these are merely validation tools requiring concomitant trial and error strategies.
Optimization strategies can be applied to provide synthesis assistance tools for which the designer simply specifies his requirement.
Thus the tool directly indicates the spring best suited to standards and requirements. Recent advances in the study of constant
pitch conical springs have provided analytical expressions of their behavior even in the non-linear phase. Considering this,
we have used optimization strategies to provide a synthesis tool for conical spring design. An example of application is presented.
The tool introduced here is thus a synthesis assistance tool that can be of considerable interest for designers who require
a conical spring in their design. 相似文献
88.
Emmanuel Osalusi Jonathan SideRobert Harris 《International Communications in Heat and Mass Transfer》2009
A broadband acoustic Doppler current profiler (ADCP) moored on the seabed at 42 m depth has been used to observe the mean and turbulent flow components in the tidally energetic Fall of Warness channel over two tidal cycles. The Reynolds stress has been estimated from the difference in variance between the along-beam velocities of opposing acoustic beams. Near bed stress at 2.63 m above seabed (mab) exceeds 7.5 Pa at the time of mean flow (speed of ~ 1.3 m s− 1) while the ebb stresses are limited to ~ 3.31 Pa during the peak ebb, mean, flow of ~ 1.3 m s− 1. The production of turbulent kinetic energy (TKE), P was found to be negative below 2 × 10− 9 W m− 3 and up to 6 × 10− 4 W m− 3 was estimated during flood flows and decreasing to 3 × 10− 4 W m− 3. The TKE dissipation rate ε was estimated by inertial dissipation method (IDM) with the greatest value of 2.43 × 10− 2 W m− 3 observed near the seabed around maximum ebb, falling to 5.75 × 10− 5 W m− 3 around slack water. The comparison between P and ε was performed by calculating individual ratios of P corresponding to ε using a bootstrap resampling technique. The study shows that the ratio ε/P averaged over whole flood and ebb were found to be ~ 0.4138 and ~ 0.4177, respectively, indicating that production exceeded dissipation. The uncertainties in Reynolds stress estimates due to instrument noise were found to be 3 × 10− 4 Pa while 4.52 × 10− 2 Pa can be attributed to the uncertainties due to the increase in the flow-related component. 相似文献
89.
Michalis Agraniotis Panagiotis Grammelis Charalambos Papapavlou Emmanuel Kakaras 《Fuel Processing Technology》2009,90(9):1071-1079
The present paper includes the results of the combustion tests with Greek dried lignite performed at a 1 MWth semi industrial scale pulverized coal combustion facility. Scope of the campaign is the investigation of the combustion behaviour of Greek lignite, i.e. temperature fields, ignition, burnout, emissions, as well as slagging and fouling tendency, while firing with varying levels of recirculated flue gas. Dry coal co-firing conditions in a large scale boiler are simulated by adjusting the volume flow of recirculated flue gas.Two test series representing different boiler operation modes are performed. During the first series the maximum flue gas temperature increase, when co-firing dry coal, is determined, while in the second test series the needed load decrease, in order to keep constant furnace outlet temperature in dry coal co-firing conditions is recorded. A detailed measurement set is carried out including temperature profiles, emissions, fuel, fly ash sampling and slagging and fouling investigations through the installation of dedicated deposition probes.The anticipated increase of the furnace temperature profiles by decreasing the inserted recirculated flue gas is confirmed by the experimental results. No clear trend of dry coal co-combustion on the emissions' behaviour is noticed, while dry coal firing appears to have a moderate effect on the deposition behaviour of Greek lignite. These preliminary investigations indicate that no significant operational problems are expected during a potential future demonstration of dry lignite co-firing in a Greek large scale boiler. 相似文献
90.