Seroprevalence of Neospora caninum infection in dairy and beef cattle in Paraguay

Seroprevalence of Neospora caninum in 879 beef and dairy cattle in different locations of Paraguay was determined by an ELISA. In the survey, 262 (29.8%) cattle were positive to N. caninum, and animals with anti-Neospora antibody titre were observed in all the locations tested in the country. Serum samples taken from a herd that exhibited persistent abortion had the highest percentage of animals being positive to the parasite (17/30, 56.7%). In the same herd, abortion was significantly more likely in animals with high anti-Neospora antibody titre. Immunoblot analysis demonstrated that the banding pattern from positive Paraguayan cattle was similar to that seen with the positive control sample. In conclusion, N. caninum infection is present among Paraguayan beef and dairy cattle, and it may be an important cause of bovine abortion in Paraguay.     

The role of river confluences and meanderings in preserving local hot spots for threatened plant species in riparian ecosystems

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Reconstitution of contractile FtsZ rings in liposomes

FtsZ is a tubulin homolog and the major cytoskeletal protein in bacterial cell division. It assembles into the Z ring, which contains FtsZ and a dozen other division proteins, and constricts to divide the cell. We have constructed a membrane-targeted FtsZ (FtsZ-mts) by splicing an amphipathic helix to its C terminus. When mixed with lipid vesicles, FtsZ-mts was incorporated into the interior of some tubular vesicles. There it formed multiple Z rings that could move laterally in both directions along the length of the liposome and coalesce into brighter Z rings. Brighter Z rings produced visible constrictions in the liposome, suggesting that FtsZ itself can assemble the Z ring and generate a force. No other proteins were needed for assembly and force generation.     

Erythromycin-resistant mutant of Escherichia coli with altered ribosomal protein component

Erythromycin combines with 50S ribosomal subunit of an erythromycin-sensitive Escherichia coli (strain Q13), while ribosomes from an erythromycin-resistant mutant from this strain have little affinity for the antibiotic. A protein component of the 50S subunit of the mutant strain is distinct from that of the parent Q13 strain.     

Protein components in the 40s ribonucleoprotein particles in Escherichia coli

The 40S ribonucleoprotein particle in Escherichia coli cells, accumulated in the presence of a low concentration of chloramphenicol, lacks at least four ribosomal structural protein components which are present in the mature 50S ribosomal subunit. The 40S ribonucleoprotein prepared by exposing the 50S ribosomal subunit to a concentrated lithium chloride solution may also be deficient in the same protein components.     

Development of suspended sediment concentration (SSC) analysis model and its application with multi-objective optimization

In Okinawa, red soil runoff emerged as a social problem long ago, and many control measures have been adopted. However, their effect has been gauged as insufficient. So, models to predict red soil runoff are required. Within this context, we have been developing the suspended sediment concentration (SSC) analysis model. In this study, the SSC analysis model, a lumped storage-type runoff model that includes a sediment runoff process, has been applied to two watersheds with different circumstances of land use. In the application of this model, we tried to do a multi-objective optimization and examined some policies concerning the choice of parameter sets. As a result, we were able to conclude that the SSC analysis model produced a good agreement between the calculated value and the observed value. In multi-objective optimization, the relation between the root mean square error (RMSE) of discharge and SSC became the Pareto relation. Moreover, it was recognized that, in taking into consideration the viewpoint of the RMSE of sediment load and the total sediment load error, the optimization of discharge should be regarded as important in choosing the set of parameters in an actual application.     

Influence of delayed timing of owners' actions on the behaviors of their dogs,Canis familiaris

This study examined the influence of delayed actions from the owner, including commands, reinforcement, and punishment, on already-learned behaviors in 10 dogs. The delay times were set to 2.0, 1.0, 0.5, 0.27, and 0.13 seconds (s). Responses to commands with a delay (Delayed) were compared with those that were not delayed (Nondelayed). The results indicated that appropriate responses to commands decreased in 2.0, 1.0, and 0.5 s delayed conditions. As delay time increased, response to commands decreased. The numbers of commands used by handlers to make their dogs obey was significantly increased with a 2.0 and 1.0 second delay compared to the nondelayed trials. The time required for dogs to obey the commands was significantly increased in 2.0, 1.0, and 0.5 s delayed conditions compared to those of the nondelayed trials. There were no significant differences between the 0.27 s, 0.13 s, and the nondelayed condition. These results suggest that timing is an important factor affecting a dog's behavior not only while learning new things, but also in the production of learned desirable behaviors that could occur during everyday interactions.