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101.
BACKGROUND: The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso‐protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep. RESULTS: Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (Rmax) increased as the amount of concentrate in the diet increased. Rmax was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, Rmax increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased. CONCLUSION: The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique. Copyright © 2011 Society of Chemical Industry  相似文献   
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Vincenzo Levis 《Calcolo》1964,1(3-4):299-336
This Note takes again a late work byM. Volpato, which indicates the resolution. with method of dynamics programming, of a non-linear problem in Econometrics, for decide theoptimum in a buying and selling business. When involved functions are linear, the question becomes aLP problem whose solutions is given from known methods. Here, subject shows, by method of Volpato, a very easy proceeding involving only comparisons among the dates of question. Moreover, the result confirms an intuitive rule of Economical Policy which, perhaps for the first time, is strictly justified.

Lavoro eseguito nell'ambito dell'attività del Gruppo di Ricerca n0 38 (Univ. ca' Foscari-Venezia) del Comitato per la matematica del C.N.R. per l'A.A. 1963–64.  相似文献   
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The first results of a new method for real-time shape acquisition with a laser scanner are presented. The new method is essentially based on the use of a laser beam and a web-cam. A digital filter parameters identification was studied for the laser line detection in the image. After this, a model for the reconstruction in real-time of the laser line in the space was developed. The first test rig was just conceived to validate the method; hence, no high resolution cameras were adopted. Nevertheless, the tests have showed encouraging results.  相似文献   
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Hyperpolarized 13C magnetic resonance spectroscopy in pig models enables cardiac metabolism assessment and provides a powerful tool for heart physiology studies, although the low molar concentration of derivate metabolites gives rise to technological limitations in terms of data quality. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance.  相似文献   
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