Respirometry, widely used to study kinetics of activated sludge, has been used to measure the oxygen uptake rate (OUR) in a nitrification biofilm process-the inverse turbulent bed reactor. The OUR has been measured at different initial concentrations of ammonia (10-100 mg N-NH4 + L-1) and nitrite (3-60 mg N-NO2-L-1), as well as those of ammonia-nitrite mixtures. The OUR was independent of the initial concentration of ammonia (zero order reaction), but decreased with time. This result can be explained by a decrease in biomass concentration within the reactor during the experiments. Between each experiment, the reactor was washed with a buffer solution at a very high flow rate, that resulted in the washing out of suspended biomass but not of fixed biomass. The loss of biomass was estimated at about 50%, indicating that half the active nitrifiers in the reactor were in the form of suspended biomass. The biomass concentration within the reactor was estimated using a mathematical model and the values obtained were in agreement with the hypothesis.

Rhodesgrass (Chloris gayana Kunth) is a highly variable, perennial forage grass widely cultivated in all tropical and subtropical regions of the world. Despite its economic importance, there is a lack of information on the genetic diversity within and among rhodesgrass cultivars, which are all based on genetic resources initially introduced from East and South Africa. The objective of this study was to assess genetic diversity within and among 13 cultivars of diploid rhodesgrass and to determine whether recent breeding efforts have resulted in cultivars distinct from the African source populations. For each cultivar, 15 individuals were examined for 237 amplified fragment length polymorphism (AFLP) markers generated from three EcoRI/MseI primer pairs. Partition of the variation revealed that the major proportion of the total genetic variation occurred within cultivars and with only 12 to 13% attributed to geographical origin or breeding history. Cluster analysis revealed three distinct groups among the cultivars investigated. Group one consisted mainly of recent Japanese cultivars and their African source population, group two contained mostly African cultivars, and group three contained one African cultivar. However, the genetic diversity within recent Japanese cultivars was comparable to the diversity within old African cultivars and there was no evidence of a reduced genetic base because of breeding efforts.

The aim of the study was to evaluate the diagnostic value of thoracic percussion and ultrasonography with the help of distance measurements and statistical methods in the determination of the caudal lung border in horses with recurrent airway obstruction (RAO). Examinations were performed on 11 healthy, warm-blooded horses of different breeds, age and grade of disease. First, the caudal lung border was determined by the traditional indirect percussion method in the 10th, 12th, 14th and 16th intercostal spaces at the end of inspiration and expiration on both sides of the thorax. To apply standardised measurements, a fix point was chosen as described earlier by the same authors for healthy horses. The distance between this point and the caudal lung border was measured with a tape-measure. Percussion was followed by ultrasonographic determination of the caudal lung border. Measurements were performed in the same way as described for the percussion technique. Mean values and standard errors of absolute values of differences between percussion and ultrasonographic measurements were the following, in centimetres (10th, 12th, 14th and 16th intercostal spaces). Left side expiration: 1.4, 0.4; 0.8, 0.2; 0.9, 0.2; 0.8, 0.4; left side inspiration: 0.8, 0.3; 1.5, 0.3; 1.4, 0.3; 1.1, 0.3; right side expiration: 2.1, 1.0; 2.1, 0.5; 1.6, 0.5; 0.8, 0.1; right side inspiration: 1.5, 0.7; 1.2, 0.6; 0.8, 0.2; 0.8, 0.3, respectively. Ultrasonography proved to be reliable in determining the caudal lung borders in horses with RAO. Results of the percussion examination did not differ significantly from those of the ultrasound method which was used as a reference technique. The differences between inspiration and expiration were greater in horses with RAO than in healthy horses in a previous study. Based on these results, percussion can be used as an integrated part of the physical examination in diagnosing caudal shift of the caudal lung border of horses suffering from RAO.

Self-incompatibility (SI) prevents self-fertilization by rejecting pollen from plants with the same S phenotype. The Brassica SI system is controlled sporophytically by multiple alleles at the single locus, S, and dominance relationships among S haplotypes are observed in both stigma and pollen. We have identified previously five different class-II S haplotypes in Brassica campestris. Here, we performed test-crosses between S heterozygotes and their respective parental S homozygotes for four of these class-II S haplotypes, and observed a linear dominance relationship on the pollen side. To determine how this relationship is controlled, we performed RNA gel blot analyses for six S heterozygotes and their respective parental S homozygotes using the corresponding SP11 clone as a probe. In all six S heterozygotes, SP11 derived from a dominant haplotype was predominantly expressed, and SP11 derived from a recessive haplotype was repressed. Thus, the linear dominance relationship of the SI phenotype on the pollen side is regulated by the expression of SP11.

The triplet states in plant photosystem II (PS II), 3P680, and from chlorophyll a, 3Chl a, in organic solution have been investigated using pulse ENDOR combined with repetitive laser excitation at cryogenic temperature with the aim to obtain their hyperfine (hf) structure. The large zero field splitting (ZFS) tensor of 3P680 enabled orientation selection via the electron spin resonance (EPR) field setting along the ZFS tensor axes. ENDOR spectra have been obtained for the first time also for the in-plane X- and Y-orientations of the ZFS tensor. This allowed a full determination of the hf-tensors of the three methine protons and one methyl group of 3P680. Based on the orientations of the axes of these hf-tensors, a unique orientation of the axes of the ZFS tensor of 3P680 in the Chl a molecular frame was obtained. These data serve as a structural basis for determining the orientation of 3P680 in the PS II protein complex by EPR on single crystals (see M. Kammel et al. in this issue). The data obtained represent the first complete set of the larger hf-tensors of the triplet state 3P680. They reflect the spin density distribution both in the highest occupied (HOMO) and lowest unoccupied (LUMO) orbitals. The data clearly confirm that 3P680 is a monomeric Chl a species at low temperature (T=10 K) used, as has been proposed earlier based on D- and E-values obtained from EPR and optically detected magnetic resonance (ODMR) studies. Comparison with the hf data for the cation and anion radicals of Chl a indicates a redistribution of spin densities in particular for the LUMO orbital of the triplet states. The electron spin distribution in the LUMO orbital is of special interest since it harbours the excited electron in the excited P680 singlet state, from which light-induced electron transfer proceeds. Observed shifts of hf couplings from individual nuclei of 3P680 as compared with 3Chl a in organic solution are of special interest, since they indicate specific protein interactions, e.g. hydrogen bonding, which might be used in future studies for assigning 3P680 to a particular chlorophyll molecule in PS II.

The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 exhibits considerable sequence heterogeneity among EBV isolateds. Seven distinct EBV strains have been defined based on sequence polymorphisms in the LMP1 gene, which are designated China 1, China 2, China 3, Alaskan, Mediterranean, NC, and the B95-8 strains

OBJECTIVE: To evaluate whether postprandial abnormalities of energy expenditure and/or lipid oxidation are present in healthy, normal-weight subjects with a strong family history of obesity and thus at high risk to become obese. DESIGN: Case-control study. SUBJECTS: A total of 16 young healthy men participated in the study. Eight subjects had both parents overweight (father's and mother's body mass index (BMI) >25 kg/m2) and eight had both parents with normal body weight (father's and mother's BMI<25 kg/m2, respectively). The group of subjects with overweight parents was similar to that with normal-weight parents (control group) in terms of BMI (23.7±1.7 vs 22.7±1.1 kg/m2) (M±s.d.) and fat-free body mass (FFM) (60.5±4.9 vs 58.4±2.0 kg), but was slightly older than the control group (25.4±3.3 vs 22.7±2.4 y; P<0.05). MEASUREMENTS: Energy expenditure (EE) was measured by indirect calorimetry, and blood samples were taken for the evaluation of metabolic variables in the fasting state and every hour for 8 h after a standard fat-rich meal (protein 15%, carbohydrate 34%, fat 51%, 4090 kJ). RESULTS: Fasting plasma glucose, cholesterol, HDL-cholesterol, triglyceride, free fatty acid (FFA) and leptin concentrations were similar in both groups of participants, but subjects with overweight parents has significantly lower plasma insulin concentrations (5.11±0.51 vs 7.07±1.56 μU/ml; P<0.007) and HOMA index of insulin resistance (1.1±0.1 vs 1.6±0.4; P<0.01). Postprandial plasma glucose, triglyceride, FFA and leptin concentrations were similar in the two groups, whereas insulin levels were significantly lower in the group with both parents overweight at 3, 5, 6, 7 and 8 h. Fasting and postprandial EE, and fasting lipid and carbohydrate oxidation were similar in both groups. On the contrary, postprandial carbohydrate oxidation (incremental area under curve) was significantly higher (196.25±94.75 vs 75.88±74.72 mg/kg FFM 8 h; P<0.007) and that of lipid oxidation lower (90.93±80.32 vs 163.68±108.22 mg/kg FFM 8 h; P<0.05) in the group of subjects with overweight parents. CONCLUSION: Normal-weight subjects with a strong family history of obesity present a reduced lipid oxidation in the postprandial period and a metabolic profile characterized by low plasma insulin levels and the HOMA index, which is compatible with increased insulin sensitivity. These metabolic characteristics may be considered as early predictors of weight gain and are probably genetically determined.

A simple and rapid method for the determination of lithium in whole bloodusing Flame atomic emission spectrometry is described. No sample preparationwas required apart from dilution with 0.02 N HNO3. The reliability of themethod was determined by analyzing Standard Reference Material (SRM) underidentical experimental conditions and comparing the determined lithiumconcentration with the reported value. These were in good agreement witheach other. The determined range of lithium in the whole blood of fifty-sixhealthy adult volunteers (28 males and 28 females) was 13.1 - 47.8 mug L-1.The determined average concentration of lithium in whole blood was comparedwith the reported values of other countries. The data was statisticallyanalyzed with respect to sex and different age groups.