A high-resolution radiation hybrid map of the human genome draft sequence

We have constructed a physical map of the human genome by using a panel of 90 whole-genome radiation hybrids (the TNG panel) in conjunction with 40,322 sequence-tagged sites (STSs) derived from random genomic sequences as well as expressed sequences. Of 36,678 STSs on the TNG radiation hybrid map, only 3604 (9.8%) were absent from the unassembled draft sequence of the human genome. Of 20,030 STSs ordered on the TNG map as well as the assembled human genome draft sequence and the Celera assembled human genome sequence, 36% of the STSs had a discrepant order between the working draft sequence and the Celera sequence. The TNG map order was identical to one of the two sequence orders in 60% of these discrepant cases.     

THE VISUAL ESTIMATION OF PASTURE AVAILABILITY USING STANDARD PASTURE CORES

A coring technique (6), that may be used for estimating the mean amount of herbage on closely grazed pastures, has been adapted to include visual scoring. Two methods are described, both of which use sets of pasture cores from the sward as reference standards. The observers score the herbage on view at random sites against the standards. In the first method the scores are converted to herbage yields directly by reference to the yields of the standards. In the second method a double sampling regression technique is used and the set of standards is used as a visual guide only.     

Voyager 1 in the foreshock, termination shock, and heliosheath

Voyager 1 (V1) began measuring precursor energetic ions and electrons from the heliospheric termination shock (TS) in July 2002. During the ensuing 2.5 years, average particle intensities rose as V1 penetrated deeper into the energetic particle foreshock of the TS. Throughout 2004, V1 observed even larger, fluctuating intensities of ions from 40 kiloelectron volts (keV) to >/=50 megaelectron volts per nucleon and of electrons from >26 keV to >/=350 keV. On day 350 of 2004 (2004/350), V1 observed an intensity spike of ions and electrons that was followed by a sustained factor of 10 increase at the lowest energies and lesser increases at higher energies, larger than any intensities since V1 was at 15 astronomical units in 1982. The estimated solar wind radial flow speed was positive (outward) at approximately +100 kilometers per second (km s(-1)) from 2004/352 until 2005/018, when the radial flows became predominantly negative (sunward) and fluctuated between approximately -50 and 0 km s(-1) until about 2005/110; they then became more positive, with recent values (2005/179) of approximately +50 km s(-1). The energetic proton spectrum averaged over the postshock period is apparently dominated by strongly heated interstellar pickup ions. We interpret these observations as evidence that V1 was crossed by the TS on 2004/351 (during a tracking gap) at 94.0 astronomical units, evidently as the shock was moving radially inward in response to decreasing solar wind ram pressure, and that V1 has remained in the heliosheath until at least mid-2005.     

Phylogenetic characterization of rabies virus isolates from Carnivora in Brazil

The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.     

A yield-independent, 15N-isotope dilution method to estimate legume symbiotic dependence without a non-N2-fixing reference plant

The proportional contribution of atmospheric N₂ to the N nutrition of lupin (P _atm) was estimated in a field experiment following addition of NH₄Cl of KNO₃ to unconfined microplots (1.5 m²) at 2.5 g N m^-2 (10 atom% ¹⁵N). The integrated ¹⁵N enrichment, or mean pool abundance, of nitrate extracted from 0- to 15-cm samples taken under the lupin crop on eight occasion between 28 and 190 days after sowing was used as the reference criterion to estimate P _atm by the ¹⁵N-isotope dilution technique. Estimates of P _atm were similar to those obtained using canola as a non-fixing reference plant, but were higher than estimates obtained using a yield-dependent model. Use of mean pool abundance obviates the need for a non-fixing reference plant, and the frequent sampling and isotope-ratio analysis of the legume biomass required with the yield-dependent model is unnecessary. However, further work is needed to validate a sampling strategy commensurate with the growth of the legume roots.     

Collaborative study of the colorimetric determination of nitrate and nitrite in cheese.

A quantitative colorimetric method for the determination of nitrate and nitrite in cheese has been subjected to collaborative study. The method includes clarification of an aqueous extract of cheese with zinc hydroxide, reduction of nitrate to nitrite via a spongy cadmium collumn (the nitrite originally present is unaltered), diazotization of sulfanilic acid with the nitrite, and coupling with 1-naphthylamine hydrochloride to form a pink azo dye whose absorbance is measured at 522 nm. The spectrophotometric responses are compared to a standard curve. In samples containing both nitrate and nitrite, nitrate is determined by difference. A standard deviation of 5.5 was obtained (5 of 6 collaborators) when a cheese sample spiked with 276 ppm sodium nitrate was analyzed by the method. The method has been adopted as official first action.     

Health of cows,calves and young stock on 26 organic dairy herds in Sweden

The health and housing of the stock on 26 organic dairy herds in four counties in eastern Sweden were studied for one year. The herds ranged in size from 12 to 64 cows, and their milk production from 3772 to 10,334 kg per cow per year. A large-animal practitioner visited the farms three times during the year, and a random sample of a third of the cows in each herd were examined. The calves and young stock and their housing were also studied. The calves were in good condition in all but four herds; their serum immunoglobulins varied from almost none to high levels. The young stock were in good condition and in good housing in 20 herds. No cows with clinical signs of metabolic disorders were found. Body condition scores were adequate or good except in two herds. Acetone was analysed in milk samples from individual cows three to six weeks postpartum, and only sporadic cases with high levels were found. The incidence of diseases treated by a veterinarian was lower in the organic herds than the average for the conventional herds in the local dairy association. The findings at the farm visits supported these data, and it is evident that a good standard of health and welfare can be achieved in organic dairy herds.