Detecting errors that result in retractions.

We present a taxonomy of errors in the scientific literature and an account of how the errors are distributed over the categories. We have developed the taxonomy by studying substantial errors in the scientific literature as described in retraction notices published in the journal Science over the past 35 years. We then examine how the sorts of errors that lead to retracted papers can be prevented and detected, considering the perspective of collaborating scientists, journal editors and referees, and readers of the published articles.

A new twist to the No Miracles Argument for the success of science.

J. D. Trout has recently developed a new defense of scientific realism, a new version of the No Miracles Argument. I critically evaluate Trout's novel defense of realism. I argue that Trout's argument for scientific realism and the related explanation for the success of science are self-defeating. In the process of arguing against the traditional realist strategies for explaining the success of science, he inadvertently undermines his own argument.

The methodological defense of realism scrutinized.

I revisit an older defense of scientific realism, the methodological defense, a defense developed by both Popper and Feyerabend. The methodological defense of realism concerns the attitude of scientists, not philosophers of science. The methodological defense is as follows: a commitment to realism leads scientists to pursue the truth, which in turn is apt to put them in a better position to get at the truth. In contrast, anti-realists lack the tenacity required to develop a theory to its fullest. As a consequence, they are less likely to get at the truth. My aim is to show that the methodological defense is flawed. I argue that a commitment to realism does not always benefit science, and that there is reason to believe that a research community with both realists and anti-realists in it may be better suited to advancing science. A case study of the Copernican Revolution in astronomy supports this claim.

Rethinking scientific specialization.

My aim in this paper is to re-examine specialization in science. I argue that we need to acknowledge the role that conceptual changes can play in the creation of new specialties. Whereas earlier sociological accounts focus on social and instrumental changes as the cause of the creation of new specialties, I argue that conceptual changes play an important role in the creation of some scientific specialties. Specifically, I argue that conceptual developments played an important role in the creation of both endocrinology and virology.

Babesia bovis and B. bigemina DNA detected in cattle and ticks from Zimbabwe by polymerase chain reaction.

From blood collected from 94 cattle at 12 locations in the eastern and northeastern areas of Zimbabwe, DNA was extracted and analysed by polymerase chain reaction with primers previously reported to be specific for Babesia bigemina and Babesia borvis. Overall, DNA of Babesia bigemina was detected in the blood of 33/94 (35%) cattle and DNA from B. bovis was detected in 27/58 (47%) of cattle. The prevalence of DNA of B. bigemina was significantly higher in young animals (<2 years) (23/46) than in animals over 2 years of age (10/48; chi2= 8.77; P <0.01%). Although tick sampling was not thorough, Boophilus decoloratus could be collected at 7/9 sites sampled and Boophilus microplus at 4/9 sites. Of the 20 B. decoloratus allowed to oviposit before PCR analysis, 1 (5%) contained DNA that could be amplified with primers for B. bigemina while 12 (60%) were positive with primers for B. bovis. Of the B. microplus allowed to oviposit, 11/16 (69%) were positive for B. bovis DNA by PCR and 2/16 (12%) were positive for B. bigemina.

Exposure of cats in southern Africa to Coxiella burnetii, the agent of Q fever.

Recently, the domestic cat has been implicated in numerous outbreaks of Q fever in humans. To determine if cats in southern Africa are infected with the agent of Q fever we tested sera from cats in South Africa and Zimbabwe by indirect fluorescence for antibodies reactive with phase II Coxiella burnetii antigen (Nine Mile strain). Reactive antibodies were detected at titres of > or = 1/40 in sera from cats in South Africa (1/52, 2%) and Zimbabwe (15/119, 13%). Our results indicate that cats in southern Africa are infected with C. burnetii and should be considered as sources of infection for humans.

Domestic cats as indicators of the presence of spotted fever and typhus group rickettsiae.

Using indirect immunofluorescence assays, sera from cats in Zimbabwe (n = 119) and South Africa (n = 52) were found to contain antibodies reactive with Rickettsia conorii (34% and 19% respectively) and R. typhi (7% and 10% respectively). These results indicate that cats may become infected with members of the spotted fever and typhus groups of rickettsiae and that cats can, therefore, be used as indicators of the presence of these organisms.

Bartonella (Rochalimaea) henselae in southern Africa--evidence for infections in domestic cats and implications for veterinarians.

Substantial evidence has recently accumulated showing domestic cats to be the principal reservoirs of Bartonella henselae, the aetiological agent of human diseases including cat-scratch disease, bacillary angiomatosis, bacillary peliosis and a febrile bacteraemia syndrome. To determine the prevalence of antibodies reactive with Bartonella henselae in cats from southern Africa, indirect fluorescent antibody assays were carried out on feline sera from South Africa and Zimbabwe. Overall, 23% (39/171) of cats had antibody titres > or = 1/64, with cats from Zimbabwe (24%; 28/119) having higher seroprevalences than those from South Africa (21%; 11/52) although this difference was not statistically significant. The implications of these findings for veterinarians in southern Africa are discussed.