Domoic acid toxicity in Californian sea lions (Zalophus californianus): clinical signs, treatment and survival

Eighty-one Californian sea lions (Zalophus californianus) with signs of domoic acid toxicity stranded along the coast of California in 1998 when there were blooms of the domoic acid-producing alga Pseudonitzschia australis off-shore. In 2000, a further 184 sea lions stranded with similar clinical signs, but the strandings occurred both during detectable algal blooms and after the blooms had subsided. The clinical signs in these 265 Californian sea lions included seizures, ataxia, head weaving, decreased responsiveness to stimuli and scratching behaviour. Affected animals had high haematocrits, and eosinophil counts, and high activities of serum creatine kinase. They were treated supportively by using fluid therapy, diazepam, lorazepam and phenobarbitone. Fifty-five of the 81 sea lions (68 per cent) affected in 1998 and 81 of the 184 (44 per cent) affected in 2000 died despite the treatment. Three of the 23 sea lions which survived in 1998 were tracked with satellite and radiotransmitters; they travelled as far south as San Miguel Island, California, and survived for at least three months. Eleven of the 129 animals which were released stranded within four months of being released.     

Annual, career or single race records for breeding value estimation in race horses

The racing careers of 2, 3, 4, and 5-year-old Thoroughbreds and French trotters born in France between 1995 and 1999 were analysed. The horses were evaluated on a set of traits, with particular attention to annual or career earnings and number of starts.

As expected, the distributions of earnings corrected for year, age and sex are very skew and thus inappropriate for breeding value estimations. However, Log transformation results in near normal distributions more suitable for this purpose.

Another problem of annual or career earnings required a more complex approach. As most horses did not win any money in France (67% of the trotters and 41% of the Thoroughbreds), it is difficult to correctly evaluate these horses. On the other hand, a linear adjustment of the Log of earnings by the Log of the number of starts (exponential adjustment of the earning index) leads to regression coefficients close to 1. It justified the use of the Log of earnings per start and explained its higher heritability in literature. A quadratic adjustment of the Log of earnings by the Log of the number of starts (sigmoid adjustment of the earning index) improves the adjustment for the Thoroughbred only and should be implemented for these horses.

The probability of a horse to be placed according to the number of starts was also studied. It is shown that the observed percentage of non-placed horses p_s according to the number of starts, s, is in all cases inferior to the expected percentage (p_s < p₁^s). Therefore, races of the same horse cannot be considered as independent events. The percentage of horses placed and the mean earnings for each age can be combined in order to estimate the economical weights for each age class. Economical weights for the French trotter were 0.00, 0.21, 0.40, and 0.39 for 2, 3, 4, and 5-year olds respectively. They were 0.11, 0.45, 0.26 and 0.18 respectively for Thoroughbreds of the same age categories. The current tendency to move from annual or career criteria towards criteria at the race level is discussed. However, the question on how to evaluate the important proportion of horses born that never appeared in a race still remains open and should focus future research.     

Transient diabetes mellitus in a domestic ferret (Mustela putorius furo)

A 3.5-year-old spayed female ferret, fed a diet high in refined sugar, was referred for lethargy, polyuria, polydipsia, and polyphagia. Diabetic ketoacidosis was diagnosed. Treatment included insulin therapy and a low carbohydrate diet. Diabetes mellitus resolved 54 d later, and insulin therapy was discontinued. There has been no recurrence of the diabetes mellitus.     

Conserved sequence and structural elements in the HIV-1 principal neutralizing determinant

The principal neutralizing determinant (PND) of human immunodeficiency virus HIV-1 is part of a disulfide bridged loop in the third variable region of the external envelope protein, gp120. Analysis of the amino acid sequences of this domain from 245 different HIV-1 isolates revealed that the PND is less variable than thought originally. Conservation to better than 80 percent of the amino acids in 9 out of 14 positions in the central portion of the PND and the occurrence of particular oligopeptide sequences in a majority of the isolates suggest that there are constraints on PND variability. One constraining influence may be the structural motif (beta strand--type II beta turn--beta strand--alpha helix) predicted for the consensus PND sequence by a neural network approach. Isolates with a PND similar to the commonly investigated human T cell lymphoma virus IIIB (HTLV-IIIB) and LAV-1 (BRU) strains were rare, and only 14 percent of sera from 86 randomly selected HIV-1 seropositive donors contained antibodies that recognized the PND of these virus isolates. In contrast, over 65 percent of these sera reacted with peptides containing more common PND sequences. These results suggest that HIV vaccine immunogens chosen because of their similarity to the consensus PND sequence and structure are likely to induce antibodies that neutralize a majority of HIV-1 isolates.     

Industrial innovation policy: lessons from american history

The historical interrelations of government support of R & D and technical change in seven major American industries point to three types of policy that have been successful in the past: (i) government R & D support for technologies in which the government has a strong and direct procurement interest; (ii) decentralized systems of government-supported research in the "generic" area between the basic and the applied; and (iii) a decentralized system of clientele-oriented support for applied R & D. A fourth type of policy, under which the government attempts to "pick winners" in commercial applied R & D, has been a clear-cut failure.     

Electronic structure and valence-bond band structure of cuprate superconducting materials

From ab initio calculations on various clusters representing the La2-xSrxCu(1)O(4) and Y(1)Ba(2)Cu(3)O(7) classes of high-temperature superconductors, it is shown that (i) all copper sites have a Cu(II)(d(9))oxidation state with one unpaired spin that is coupled antiferromagnetically to the spins of adjacent Cu(II) sites; (ii) oxidation beyond the cupric (Cu(II)) state leads not to Cu(III) but rather to oxidized oxygen atoms, with an oxygen ppi hole bridging two Cu(II) sites; (iii) the oxygen ppihole at these oxidized sites is ferromagnetically coupled to the adjacent Cu(II)d electrons despite the fact that this is opposed by the direct dd exchange; and (iv) the hopping of these oxygen ppi holes (in CuO sheets or chains) from site to site is responsible for the conductivity in these systems (N-electron band structures are reported for the migration of these localized charges).