Babesial antibody dynamics after cattle immunisation with live vaccines, measured with an indirect immunofluorescence test

The efficacy of vaccination of Argentinean cattle against babesiosis and anaplasmosis using live immunogens was tested to detect specific antibodies in samples obtained about 60 days after vaccination. Under these conditions a higher than expected proportion of cattle failed to show antibodies against Babesia bigemina. Therefore, a study was designed to evaluate if this failure was due to insensitivity of the routine test to detect antibodies to B. bigemina or to lack of infectivity of the live vaccine. Four groups (G) of cattle were each inoculated subcutaneously with 10 million Babesia bovis (vaccinal strain R1A), 10 million B. bigemina (vaccinal strain S1A) and 10 million Anaplasma centrale (strain M1). G1 and G2 consisted of ten Angus bulls 20-24 months old and ten Angus bulls 15-18 months old, respectively; G3 and G4 consisted of ten and 16 Holstein 1-month-old male calves, respectively. Blood samples were obtained on days 0, 10, 20, 30, 40, 50 and 60 after vaccination and the sera were analysed with an indirect immunofluorescent (IFA) test to detect antibodies to B. bovis (baseline dilution for a positive result 1:60) and B. bigemina (baseline dilution 1:120). Positive IFA titres were considered as evidence of the infectivity of the Babesia vaccinal strains contained in the vaccine. All Angus bulls were found positive to antibodies against both Babesia species, by day 20 (B. bovis) and day 30 (B. bigemina), whereas 10-25% of Holstein calves were negative throughout. The partial lack of vaccine infectivity in the calves was considered to be a consequence of innate resistance of young calves to Babesia. Antibody titres to B. bovis and B. bigemina declined by day 60 after vaccination. However, all cattle that were positive to B. bovis antibodies on day 50 were still positive to the IFA test 10 days later while 10%, 30% and 12% of cattle of G1, G2 and G3 that were positive to B. bigemina antibodies on day 50 after vaccination were found negative to the IFA test on day 60. In future, samples taken on days 40-50 will be used for detection of B. bigemina antibodies in vaccinated cattle, on day 60 for A. centrale and on either occasion for B. bovis. The reaction to the inoculation of B. bigemina S1A strain appears to lag behind the reaction to B. bovis R1A strain. It is not certain if this is a normal reaction to this B. bigemina strain or the result of interaction with the B. bovis strain.     

Essential phospholipids in the treatment of chronic pyelonephritis]

Through TCD test, observation on the blood flow dynamics change before and after treatment with 31 cases of the child cerebral atrophy was made. It is found that scalp therapy is able to speed up the blood flow of part artery, especially increase the even blood flow speed of MCA, ACA obviously (P < 0.05), which preliminary shows the mechanism of scalp therapy for child cerebral atrophy mean while. It is found that scalp therapy also has the function to restrain epilepsy.     

The early diagnosis of the severity of blast trauma to the brain and auditory system]

This paper presents the information on the early period of an explosive head trauma and trauma to the auditory system. Different types of hearing impairment, the staging of the pathological process were determined along with various immunological and biochemical changes occurring in this group of patients. The results of the study call for necessity of the early ENT observation of all patients in whom an explosive trauma is suspected.     

The fracture stress of chemical vapour deposited diamond

The factors which control the fracture stress of chemical vapour deposited diamond have been studied using the 3-point bend geometry. Fracture stress values of 300–800 MPa for the growth side and 600–1200 MPa for the nucleation side were recorded for samples of thickness 0.4–2.4 mm. A Weibull modulus of 23 was calculated for the growth surface data, showing that the fracture stress variability was low for a brittle material. A theory based on these results demonstrates that the material behaviour is remarkably simple, depending only on the grain size and the sample thickness, regardless of wide variations in other parameters such as optical transmission and stress state. The paper also contains a possible explanation for this well-defined behaviour based on microstress variations resulting from differences in defect density in different growth sectors within a grain.     

Study of correlations in DNA sequences

We present a method for unified statistical analysis of short and long range correlations between various nucleotides in genomic DNA strands. The approach is based on the mutual study of Fourier structure factor spectra and pair correlation functions. The analysis of cross correlations in the different ranges of structural spectra permits identification of the main sources of correlations, namely, the coherent point mutations, coincident periodicities or large scale density variations. The technique for assessment of structural coupling between various genes in the genome is also described.     

Shear and extensional flow of a thermotropic liquid crystalline polymer

The flow of a thermotropic liquid crystalline polymer (unfilled and glass fiber filled) was studied using a capillary rheometer and an instrumented injection molding machine. Despite different thermal histories, the techniques gave similar results. From 330 to 350°C, viscosity was independent of temperature. At 340°C, where most measurements were carried out, pronounced shear-thinning occurred and the shear flow curves were nonlinear, the power law exponent decreasing from 0.51 at a shear rate of 10 s⁻¹ to 0.35 at 10⁴ s⁻¹. A previously reported model was used to derive elongational flow curves from die entry pressure data. Because of the nonlinearity of the flow curves, quadratic log-stress vs. log-strain rate plots were needed to model behavior over the strain rate region studied. The elongational flow curves were similar in shape to the shear flow curves, with an effective Trouton ratio of 30. Despite orientation and structure present in the melt, the extensional viscosities and Trouton ratios were within the range found with normal thermoplastic melts. The results suggest that extensional flow may be inhomogeneous, the flowing units possibly being partially ordered domains.     

A specification test for univariate and multivariate proportional hazards models

This paper applies White's (1982, Econometrica 50, 1-25) information matrix (IM) test for correct model specification to proportional hazards models of univariate and multivariate censored survival data. Several alternative estimators of the test statistic are presented and their size performance examined. White also suggested an estimator of the parameter covariance matrix that was robust to certain forms of model misspecification. This has been subsequently proposed by others (e.g., Royall, 1986, International Statistical Review 54, 221-226) and applied by Huster, Brookmeyer, and Self (1989, Biometrics 45, 145-156) as part of an independence working model (IWM) approach to multivariate censored survival data. We illustrate how the IM test can be used for both univariate data and as part of the IWM approach to multivariate data.