Fructan utilizing strains of lactic acid bacteria were assessed for their potential as silage inoculants during ensilage with herbage harvested from a mixed sward of ryegrass. The experiment included five treatments: uninoculated herbage as a control, herbage inoculated with one of three fructan utilizing strains (Lactobacillus paracasei ssp. paracasei P4134 and Lact. plantarum V54/6 & V57/5) or inoculated with a non-fructan degrading strain (Lact. plantarum P3775). It was clearly demonstrated that inoculant strains dominated the lactic acid bacteria population during the first 14 days of ensilage. All inoculated silages underwent a rapid lactic acid fermentation with lactic acid bacteria numbers increasing to ×10 9 by day 2 and pH falling to ¾4·0 by day 3. Rates of fructan degradation were, however, considerably reduced in silages inoculated with Lact. plantarum P3775 compared with the fructan utilizing strains. Inoculation with Lact. plantarum P3775 also resulted in slightly lower levels of lactic acid production during the first 14 days of ensilage compared with other strains. While rates of fructan degradation in untreated herbage were comparable with those observed in herbage inoculated with fructan degrading strains, resulting silages were less well fermented. The majority of lactic acid bacteria isolated from untreated silages were unable to utilize fructan and the observed rate of breakdown is attributed to plant fructan hydrolases and possibly activity of other micro-organisms. The proportion of L-isomer in total lactic acid formed during ensilage was also analysed. The highest proportion of this isomer was detected in Lact. paracasei ssp. paracasei P4134 inoculated silage (370%), with intermediate values in untreated silages (350%) and lowest values being found in silages inoculated with strains of Lact. plantarum (330%). This study highlights the potential of fructan degrading strains of lactic acid bacteria as silage inoculants and also that of strains of Lact. paracasei ssp. paracasei to manipulate the relative proportions of lactic acid isomers formed during ensilage.

In this paper we study ultrasonic imaging in air using an array of transducers. We describe a superresolution technique that uses the fact that most surfaces act as perfect reflectors to ultrasonic pulses in air t o generate accurate surface maps for object identification. The technique involves the minimization of a quadratic objective function subject to a nonlinear equality constraint. We show that this minimization can be accomplished by a two step penalty function method, which, although not practical on a general purpose computer, can operate in real time on a pair of neural networks. Results demonstrate that the technique generates accurate surface maps even with low receive signal-to-noise ratios.

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introduction:The Rad-87 Rainbow® SET pulse co-oximeter (Masimo Corporation) allows continuous, noninvasive monitoring of hemoglobin concentrations (SpHb). The clinical accuracy of SpHb requires further validation in the surgical ICU setting. methods: 547 patients from two adult surgical ICUs were enrolled in the study. Patients had the SpHb pulse co-oximeter placed on arrival to the ICU; Core and Stat lab Hb measurements were taken at the discretion of the clinicians, who were blinded to SpHb values. We compared all SpHb and lab values point to point and at thresholds commonly used to trigger transfusion. results: 383 patients had at least one time-paired SpHb and lab for a total of 2474 time points. There was a poor linear regression correlation between SpHb and labs [R2 = 0.29]. Concordance rates between SpHb and labs within 0.5 g/dL, 1.0 g/dL, and 2.0 g/ dL were 20.2%, 40.1%, and 70.0%, respectively. Bland-Altman analysis showed a bias of 1.0 g/dL and limits of agreement of 4.6 g/dL and -2.5 g/dL. Accuracy was best at lab values of 10.5-14.5 g/dL (bias = -0.8-0.9 g/dL) and least at lab values of 6.5-8 g/dL (bias = 1.8-3.3 g/dL). The bias was not caused by SpHb being consistently lower in some patients and higher in others. When sequential lab values declined below 8 g/dL, the sensitivity and specificity of SpHb were 16% and 95% (N=103); at 7 g/dL, they were 7% and 99% (N=13). At a threshold of 8 g/dL, continuous SpHb values predicted the need for transfusion before the labs in 44 of 103 instances (43%); at 7 g/dL, it did so in 4 of 13 instances (31%). The predictive utility of SpHb was consistent within individual patients but not across patients (P=0.002) and was not influenced by age, sex, ethnicity, or BMI. conclusions: SpHb shows a greater bias in ICU patients than has previously been reported, especially at lower Hb ranges. There appears to be no consistent or predictable bias across different patient groups. Based on these results noninvasive Hb monitoring has poor sensitivity at critical Hb thresholds and is unable to identify the need for transfusion before labs in most patients. The accuracy of SpHb needs to be improved to support clinical decision-making in surgical critical care patients.