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61.
62.
This study reports on a multivariate analysis of the moving bed biofilm reactor (MBBR) wastewater treatment system at a Canadian pulp mill. The modelling approach involved a data overview by principal component analysis (PCA) followed by partial least squares (PLS) modelling with the objective of explaining and predicting changes in the BOD output of the reactor. Over two years of data with 87 process measurements were used to build the models. Variables were collected from the MBBR control scheme as well as upstream in the bleach plant and in digestion. To account for process dynamics, a variable lagging approach was used for variables with significant temporal correlations. It was found that wood type pulped at the mill was a significant variable governing reactor performance. Other important variables included flow parameters, faults in the temperature or pH control of the reactor, and some potential indirect indicators of biomass activity (residual nitrogen and pH out). The most predictive model was found to have an RMSEP value of 606 kgBOD/d, representing a 14.5% average error. This was a good fit, given the measurement error of the BOD test. Overall, the statistical approach was effective in describing and predicting MBBR treatment performance. 相似文献
63.
ABSTRACT: The effect of post-cooking holding-time on sensory assessment of low (89 g/kg) and high (218 g/kg) fat beefburgers was assessed. Burgers were served to panelists approximately 3 or 18 min after cooking. Fat content influenced fattiness, moistness/juiciness and overall appearance (P < 0.05), overall acceptability and overall texture (P< 0.01) and tenderness and crumbliness (p<0.001). Burgers with the higher fat content had higher scores. Holding-time influenced sensory overall appearance only with lower scores at extended holding times (P < 0.01). Treatment differences were small, mostly less than one sensory scale unit. Higher lightness and yellowness values were found for burgers with higher fat contents. 相似文献
64.
65.
OBJECTIVES: Our purpose was to determine (1) whether a fetal acoustic stimulation test results in more palpable fetal movement compared with a mock test (control) and (2) whether palpated fetal movements after a fetal acoustic stimulation test are accompanied by a reactive nonstress test. STUDY DESIGN: In a randomized controlled trial we studied women seen in the labor and delivery suite for various indications. Women were excluded for multiple gestation, < 31 weeks' gestational age, treatment with magnesium sulfate or narcotics, or ruptured membranes. Informed consent was obtained from eligible women, who were then randomized to a test or control group. We placed an acoustic stimulator on the abdomen of each woman, but only the test group was stimulated. We assessed fetal movement by a grading system: 0 = no fetal movement felt by patient or tester, 1 = fetal movement felt by patient only, 2 = fetal movement felt by tester, 3 = visual movement seen by tester. A positive fetal acoustic stimulation test result was defined as one with any fetal movement felt or seen by the tester (grades 2 or 3). We then performed a nonstress test. We compared rates of a positive fetal acoustic stimulation test in the test and control groups with the chi 2 test. A p value < 0.05 was considered significant. RESULTS: We randomized 297 women to the test group and 280 women to the control (mock test) group. Of women tested with the fetal acoustic stimulation test. 81% had fetal movement by palpation or visualization (grades 2 or 3) compared with 19% of the control group (p < 0.0001, odds ratio 19.29, 95% confidence interval 12.42 to 30.07). Of the test group, 283 (95%) had a reactive nonstress test and 14 (5%) had nonreactive tests; the control group had 267 (95%) reactive and 13 (5%) nonreactive nonstress tests. Of 242 patients in the test group with a positive fetal acoustic stimulation test, 236 (98%) had a reactive nonstress test. Of those in the test group with fewer than three contractions per 10 minutes. 164 (89%) had a positive fetal acoustic stimulation test. Of these, 162 (99%) had a reactive nonstress test. CONCLUSION: The fetal acoustic stimulation test evokes significantly more palpated or visualized fetal movement than in controls. Palpated or visualized fetal movement after acoustic stimulation was almost always accompanied by a reactive nonstress test. 相似文献
66.
Evaluation of humoral immune responses in cattle grazing endophyte-infected or endophyte-free fescue
RL Rice DJ Blodgett GG Schurig WS Swecker JP Fontenot VG Allen RM Akers 《Canadian Metallurgical Quarterly》1997,59(3-4):285-291
Anecdotal reports suggest cattle with fescue toxicosis may not respond to vaccination and thus, experience increased incidence of Bovine Respiratory Disease Complex (BRDC) when shipped to feedlots. Fescue toxicosis causes hypoprolactemia in cattle. Hypoprolactemia decreases humoral immune responses in mice. Therefore, a study was conducted to compare the magnitude of primary and secondary humoral immune responses against specific antigens in cattle grazing endophyte-infected or endophyte-free fescue. Angus steers were blocked by weight and allocated into four groups. Two groups grazed endophyte-infected (EI) fescue and the other two groups grazed endophyte-free (EF) fescue. All steers were injected IM on d 0 and 21 with lysozyme without adjuvant and concanavalin. A (Con A) with sheep red blood cells (SRBC) in incomplete adjuvant of Freund. Steers were bled on days 0, 21 and 35 post-vaccination. Average daily gains (ADG), alkaline phosphatase (ALP) activity, cholesterol concentrations, rectal temperatures, and serum prolactin concentrations were measured to confirm fescue toxicosis in steers grazing EI fescue. Antibodies to Con A and SRBC were determined by ELISA and hemagglutination assay, respectively. The ADG were decreased for the EI group during the first month. Rectal temperature were elevated and serum prolactin concentrations were decreased in the EI group. Cholesterol and ALP concentrations also were decreased in the EI group. Primary and secondary immune responses against Con A tended to be increased and were increased against SRBC in the EI group. Antibodies against lysozyme were not induced in either group. In conclusion, cattle grazing EI fescue mounted similar humoral immune responses to vaccination, despite hypoprolactemia, as cattle grazing EF fescue. Increases in bovine respiratory disease in cattle maintained on EI fescue probably is not associated with lack of humoral immune response to vaccination protocols as a result of fescue toxicosis. 相似文献
67.
A rapid and convenient method for the measurement of bicarbonate, carbonate, or carbon dioxide in water was developed using fourier transform infrared spectroscopy (FTIR). Bicarbonate and carbonate are converted to carbon dioxide by lowering the pH of the solution, then the absorbance of the dissolved carbon dioxide at 2345 wavenumbers is measured using a liquid sample cell. If the measurement of dissolved carbon dioxide is the objective, the pH is not adjusted, and the carbon dioxide in the free form can be measured without interference from low levels of carbonates. The method is linear from 10.48 ppm to a minimum of 366.8 ppm carbon dioxide (r squared = 0.9996). The coefficient of variation at 10.48 ppm (LOD 3 signal/noise), 52.4 ppm, and 262 ppm is 45.6, 4.0, and 3.9, respectively. The average percent recovery at 10.48 ppm, 52.4 ppm, and 262 ppm is 74.5, 104.2, and 104.0, respectively. 相似文献
68.
A new technique for right heart catheterization using a Mullins' sheath is described. This device allows a Swan-Ganz catheter to reach pulmonary artery position easily and permits simultaneous pressure recordings in right heart chambers, thus avoiding a double venous puncture and two catheters. This new technique, its indications, and our experience in 29 patients are described. It is most useful in patients with severe pulmonary hypertension and in those conditions in which accurate right heart pressure measurements are needed. 相似文献
69.
The treatment of patients with uterine neoplasms may be significantly altered by the stage of disease at the time of diagnosis. A noninvasive and accurate means of staging these tumors is therefore desirable. This article discusses the magnetic resonance imaging techniques and findings that are essential for the accurate staging of uterine neoplasms. The imaging findings are presented following a discussion of the histopathologic findings, clinical presentation, diagnosis and staging, pathways of tumor spread, and treatment of each neoplasm. A comparison of magnetic resonance and other imaging techniques is also provided. 相似文献
70.
The shear bond strengths of the XR-Bonding System used in conjunction with Herculite composite, to the dentine of forty extracted human permanent first and second molars were determined after the test specimens were stored in physiological saline at 37 degrees C for 48 hours, one week, two weeks and four weeks, respectively. A shear load was applied to the base of the bonded composite cylinders with a knife-edged rod at a crosshead speed of 0.5 mm/minute. The shear bond strengths were expressed in megapascals (MPa). The quantitative microleakage of Class V preparations in dentine (cementum) in forty-eight extracted human maxillary permanent canines restored with the same dentinal bonding system and after storage in physiological saline at 37 degrees C for the same time intervals as for the shear bond strength tests, was determined. On the final day of each time interval the teeth were thermocycled X 500 in a 2 per cent methylene blue solution between 8 degrees C and 50 degrees C with a dwell time of 15 seconds. Microleakage was determined by a spectrophotometric dye-recovery method and expressed in microgram dye/restoration. There was a significant trend for the shear bond strengths to increase with duration of storage (p = 0.01) but the quantitative microleakage was not significantly different (p = 0.75). 相似文献