Measures of bone mineral content in mature dairy cows

The objectives of this investigation were to assess the relationship between chemical measures and imaging estimates (radiographic photometry and dual-energy x-ray absorptiometry) of bone mineral content in dairy cows and to evaluate the effects of parity, stage of lactation, and site of measurement (fused third and fourth metacarpal bone vs. caudal vertebrae 14 and 15) on bone mineral content. In a preliminary study, the caudal vertebrae were excised from 33 cows following slaughter. Samples were analyzed by radiographic photometry and then analyzed for mineral content chemically. In a second experiment, the caudal vertebrae and right front metacarpal (sample pairs) were excised from 107 Holstein cull cows following slaughter. Parity and days in milk (DIM) of the donor animals were obtained for 43 pairs of samples. Samples were grouped by parity (1, 2, 3, and >or=4) stage of lactation (Stage 1: <90 DIM, Stage 2: 90 to 150 DIM, Stage 3: 151 to 250 DIM, and Stage 4: >250 DIM). Samples were analyzed by radiographic photometry and dual-energy x-ray absorptiometry and then analyzed for mineral content chemically. In both experiments, the relationship between mineral content estimated via the imaging techniques and mineral content measured chemically was poor, likely because of the relative maturity of animals in the sample set and lack of variation in mineral content. Ash content was higher in the metacarpal than in the caudal vertebrae, as were concentrations of Mg (expressed as a proportion of bone ash). No effects of stage of lactation were observed on bone mineral in the caudal vertebrae, but in the metacarpal, P content (proportion of total mineral) was highest in second lactation cows. Total bone mineral content (ash) was not affected by parity in the metacarpal or caudal vertebra, but Ca and P content of the metacarpal increased with parity. Noninvasive imaging techniques are not sufficiently sensitive to detect changes in mineral content or composition of mature cows, and only modest changes in bone mineral were observed with stage of lactation and parity.     

Doctors and patients don't agree: cross sectional study of patients' and doctors' perceptions and assessments of disability in multiple sclerosis

OBJECTIVES: To compare the judgments of clinicians on which domains of health in the short form questionnaire (SF-36) would be most important to patients with multiple sclerosis with the opinions of patients themselves; to compare assessment of physical disability in multiple sclerosis by a clinician using Kurtzke's expanded disability status scale and a non-clinically qualified assistant using the Office of Population Census and Surveys' (OPCS) disability scale with self assessment of disability and other domains of health related quality of life by patients using the SF-36 and the EuroQol questionnaire; and to compare the scores of patients for each domain of the SF-36 with control data matched for age and sex. DESIGN: Cross sectional study. SETTING: Clinical department of neurology, Edinburgh. SUBJECTS: 42 consecutive patients with multiple sclerosis attending a neurology outpatient clinic for review or a neurology ward for rehabilitation. MAIN OUTCOME MEASURES: Scores on the SF-36; EuroQol; Kurtzke's expanded disability status scale; the OPCS disability scale. RESULTS: Patients and clinicians disagreed on which domains of health status were most important (chi 2 = 21, df = 7, P = 0.003). Patients' assessment of their physical disability using the physical functioning domain of the SF-36 was highly correlated with the clinicians' assessment (r = -0.87, P < 0.001) and the non-clinical assessment (r = -0.90, P < 0.001). However, none of the measures of physical disability correlated with overall health related quality of life measured with EuroQol, Quality of life correlated with vitality, general health, and mental health in the SF-36, each of which patients rated as more important than clinicians and for each of which patients scored lower than the controls. CONCLUSIONS: Patients with multiple sclerosis and possibly those with other chronic diseases are less concerned than their clinicians about physical disability in their illness. Clinical trials in multiple sclerosis should assess the effect of treatment on the other elements of health status that patients consider important, which are also affected by the disease process, are more closely related to overall health related quality of life, and may well be adversely affected by side effects of treatment.     

Reproductive effects of feeding gossypol and vitamin E to bulls

An experiment was conducted to determine the effects of long-term feeding of cottonseed meal on the reproductive traits of Holstein bulls. Holstein bulls approximately 6 mo of age were placed on the following treatments: 1) soybean meal + corn (CON); 2) cottonseed meal + corn (GOS); and 3) cottonseed meal + 4,000 IU vitamin E x bull(-1) x d(-1) (G+4E). The GOS and G+4E diets were formulated to supply 14 mg of free gossypol x kg(-1) BW x d(-1). These bulls had been in a previous experiment that evaluated the effects of feeding the same type of diets, but from 2 wk to 6 mo. of age. Percentage of motility, percentage of normal and live sperm, and daily sperm production were less (P<.05) in the GOS than in the other two treatments. Percentages of primary abnormalities and abnormal midpieces were greater (P<.05) in the GOS group than in the other two groups. At 12 and 16 mo. of age, bulls were given two assessments for sex drive traits. Bulls that received gossypol exhibited less sexual activity (P<.05) at the first test than bulls in other treatments. Vitamin E supplementation in bulls that received gossypol improved the number of mounts in the first test and the time to first service in the second test. There was a trend of gossypol to decrease and vitamin E to improve libido score. The results of the GOS first libido test may indicate lack of sexual maturity, which agrees with sperm production data. At the time of first test (12 mo. of age), none of GOS, two of CON, and six of G+4E bulls had reached puberty on the basis of experimental protocol. Long-term feeding of gossypol to Holstein bulls negatively affected some reproductive traits; however, vitamin E supplementation countered these adverse effects and even improved these traits.     

Phenolic composition of black tea liquors as a means of predicting price and country of origin

Seventy-seven black teas from seven countries were analysed by HPLC. The relative levels of the 11 most prominent peaks detected at 380 nm were determined. The teas were priced or scored by professional tea tasters. Statistical analysis of the HPLC results, with principal component analysis (PCA) and canonical variate analysis (CVA), highlighted the characteristic differences in phenolic constituent levels which contributed most powerfully to the discrimination between countries. Multiple regression was used to investigate the relationship between price (or score) and phenolic constituent level. Certain phenolic constituents seem to be important in determining quality but further work is recommended to ensure the significance of the observed trends.     

The Economic Design of Sampling Control Strategies for a Class of Industrial Process

Many authors have proposed models for the optimal design of control charts for the control of the defect rate for industrial processes. These models have limited the alternatives available subsequent to sampling to either rebuilding the process, or continuing to operate the process in its current state. Although the cost of rebuilding the process is treated as an adjustable parameter in these models, it can not be a negligible amount. If it were, the obvious optimal strategy would be to rebuild the process, possibly without samplings, after each batch or unit produced. This paper considers the determination of the optimal sample size and sample interval for the case where the process does not have to be rebuilt, but rather may be simply adjusted at a nominal cost after each sample. A model, which assumes a continuum of process fraction defectives, is developed and then used to explore the effect of fixed and variable sampling cost, specification limits and measurement errors on the optimal sampling policy and costs.     

Rheological study of crosslinking and gelation in chlorobutyl elastomer systems

The multiple waveform rheological technique was used to study the crosslinking behaviour of a filled elastomeric system at various temperatures. The gel point could be precisely determined from a single experiment at each temperature using this technique. At the instant of gelation, the storage (G′) and loss (G″) moduli scale with frequency in an identical manner, i.e. ωⁿ. The relaxation exponent, n was found to be approximately constant (0.14) in the temperature range studied. Reported values of n for chemically crosslinking systems are typically higher; the low value in this case can be attributed to the high molecular weight of the prepolymer and the presence of filler. The gel times at various temperatures were used to calculate an apparent activation energy of the curing reaction, which was found to be approximately 92 kJ mol⁻¹.     

Basic brick in copper converters—Their mineralogical changes

Plant experience has shown that burned chrome-magnesite and burned magnesite brick give excellent service in copper converters. This study confirms that experience, but it also notes certain differences between the two.