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Nakagawa, S. (2004). A farewell to Bonferroni: the problems of low statistical power and publication bias. Behav Ecol, 15.
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Nakagawa, S. (2004). A farewell to Bonferroni: the problems of low statistical power and publication bias. beheco, 15(6), 1044–1045.
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Verguts, T., & Fias, W. (2004). Representation of Number in Animals and Humans: A Neural Model. J. Cogn. Neurosci., 16(9), 1493–1504.
Abstract: This article addresses the representation of numerical information conveyed by nonsymbolic and symbolic stimuli. In a first simulation study, we show how number-selective neurons develop when an initially uncommitted neural network is given nonsymbolic stimuli as input (e.g., collections of dots) under unsupervised learning. The resultant network is able to account for the distance and size effects, two ubiquitous effects in numerical cognition. Furthermore, the properties of the network units conform in detail to the characteristics of recently discovered number-selective neurons. In a second study, we simulate symbol learning by presenting symbolic and nonsymbolic input simultaneously. The same number-selective neurons learn to represent the numerical meaning of symbols. In doing so, they show properties reminiscent of the originally available number-selective neurons, but at the same time, the representational efficiency of the neurons is increased when presented with symbolic input. This finding presents a concrete proposal on the linkage between higher order numerical cognition and more primitive numerical abilities and generates specific predictions on the neural substrate of number processing. N1 -
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Traversa, D., Giangaspero, A., Galli, P., Paoletti, B., Otranto, D., & Gasser, R. B. (2004). Specific identification of Habronema microstoma and Habronema muscae (Spirurida, Habronematidae) by PCR using markers in ribosomal DNA. Mol Cell Probes, 18(4), 215–221.
Abstract: Gastric or cutaneous habronemosis caused by Habronema microstoma Creplin, 1849 and Habronema muscae Carter, 1865 is a parasitic disease of equids transmitted by muscid flies. There is a paucity of information on the epidemiology of this disease, which is mainly due to limitations with diagnosis in the live animal and with the identification of the parasites in the intermediate hosts. To overcome such limitations, a molecular approach, based on the use of genetic markers in the second internal transcribed spacer (ITS-2) of ribosomal DNA, was established for the two species of Habronema. Characterisation of the ITS-2 revealed sequence lengths and G+C contents of 296 bp and 29.5% for H. microstoma, and of 334 bp and 35.9% for H. muscae, respectively. Exploiting the sequence difference (approximately 40%) between the two species of nematode, primers were designed and tested by the polymerase chain reaction (PCR) for their specificity using a panel of control DNA samples from common equid endoparasites, and from host tissues, faeces or muscid flies. Effective amplification from each of the two species of Habronema was achieved from as little as 10 pg of genomic DNA. Hence, this molecular approach allows the specific identification and differentiation of the DNA from H. microstoma and H. muscae, and could thus provide a molecular tool for the specific detection of Habronema DNA (irrespective of developmental stage) from faeces, skin and muscid fly samples. The establishment of this tool has important implications for the specific diagnosis of clinical cases of gastric and cutaneous habronemosis in equids, and for studying the ecology and epidemiology of the two species of Habronema.
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Gasser, R. B., Hung, G. - C., Chilton, N. B., & Beveridge, I. (2004). Advances in developing molecular-diagnostic tools for strongyloid nematodes of equids: fundamental and applied implications. Mol Cell Probes, 18(1), 3–16.
Abstract: Infections of equids with parasitic nematodes of the order Strongylida (subfamilies Strongylinae and Cyathostominae) are of major veterinary importance. In last decades, the widespread use of drugs against these parasites has led to problems of resistance within the Cyathostominae, and to an increase in their prevalence and intensity of infection. Novel control strategies, based on improved knowledge of parasite biology and epidemiology, have thus become important. However, there are substantial limitations in the understanding of fundamental biological and systematic aspects of these parasites, which have been due largely to limitations in their specific identification and diagnosis using traditional, morphological approaches. Recently, there has been progress in the development of DNA-based approaches for the specific identification of strongyloids of equids for systematic studies and disease diagnosis. The present article briefly reviews information on the classification, biology, pathogenesis, epidemiology of equine strongyloids and the diagnosis of infections, highlights knowledge gaps in these areas, describes recent advances in the use of molecular techniques for the genetic characterisation, specific identification and differentiation of strongyloids of equids as a basis for fundamental investigations of the systematics, population biology and ecology.
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RHO, J. R., SRYGLEY, R. B., & CHOE, J. C. (2004). Behavioral ecology of the Jeju pony (Equus caballus): Effects of maternal age, maternal dominance hierarchy and foal age on mare aggression. Ecol. Res., 19(1), 55–63.
Abstract: On Jeju Island, Korea, dominance hierarchy and maternal care according to maternal age were studied in a herd of Jeju ponies (Equus caballus), consisting of 73 mares, their foals and one stallion. Dominance ranks were nearly linear and increased significantly with the age of mares. Most aggressive encounters involved mares under 5 years old. Mares under the age of 5 years have apparently not established their rank. The mean frequency of aggressive actions of mares per hour increased significantly as the day of parturition approached. Aggressive actions of mares with foals decreased significantly as their foals aged. The overall frequency of aggression of mares with foals also decreased significantly with the age of the mares. Our results suggest that the cost of maternal care is lower for older, more dominant mares than for subordinate ones.
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Sih, A., Bell, A., & Johnson, J. C. (2004). Behavioral syndromes: an ecological and evolutionary overview. Trends. Ecol. Evol, 19(7), 372–378.
Abstract: Recent studies suggest that populations and species often exhibit behavioral syndromes; that is, suites of correlated behaviors across situations. An example is an aggression syndrome where some individuals are more aggressive, whereas others are less aggressive across a range of situations and contexts. The existence of behavioral syndromes focuses the attention of behavioral ecologists on limited (less than optimal) behavioral plasticity and behavioral carryovers across situations, rather than on optimal plasticity in each isolated situation. Behavioral syndromes can explain behaviors that appear strikingly non-adaptive in an isolated context (e.g. inappropriately high activity when predators are present, or excessive sexual cannibalism). Behavioral syndromes can also help to explain the maintenance of individual variation in behavioral types, a phenomenon that is ubiquitous, but often ignored. Recent studies suggest that the behavioral type of an individual, population or species can have important ecological and evolutionary implications, including major effects on species distributions, on the relative tendencies of species to be invasive or to respond well to environmental change, and on speciation rates. Although most studies of behavioral syndromes to date have focused on a few organisms, mainly in the laboratory, further work on other species, particularly in the field, should yield numerous new insights.
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List, C. (2004). Democracy in animal groups: a political science perspective. Trends Ecol Evol, 19(4), 168–169.
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Dargatz, D. A., & Traub-Dargatz, J. L. (2004). Multidrug-resistant Salmonella and nosocomial infections. Vet Clin North Am Equine Pract, 20(3), 587–600.
Abstract: Nosocomial infections are a serious threat to optimum patient care. In addition, nosocomial infections can have far-reaching consequences for the hospital personnel and the financial aspects of the hospital. Nosocomial infections with Salmonella spp have been described among hospitalized equine populations more frequently than any other agent. Salmonella spp associated with hospitalized equids often possess more antimicrobial resistance determinants than do Salmonella spp isolated from healthy horses in the general population. There is little evidence to suggest that resistant salmonellae are more virulent than nonresistant forms. MDR forms of Salmonella complicate the selection of appropriate antimicrobials when they are indicated, however. Furthermore, the use of some antimicrobials may apply selection pressure toward enhanced ability of MDR Salmonella to colonize equine patients. Further research should help to elucidate the risky uses of antimicrobials in the hospital setting and define the role of disinfectants and treatments such as NSAIDs in the ecology of MDR forms of nosocomial infections, including Salmonella. In the meantime, thoughtful selection of when and how to use antimicrobials in equine patients, together with deliberate selection of which antimicrobials to use based on monitoring data and other factors, such as safety and spectrum, is advised.
Keywords: Animals; Anti-Bacterial Agents/*pharmacology; Cross Infection/prevention & control/*veterinary; Disease Outbreaks/prevention & control/veterinary; Drug Resistance, Bacterial; *Drug Resistance, Multiple, Bacterial; Horse Diseases/*drug therapy/transmission; Horses; Infection Control/methods; Microbial Sensitivity Tests/veterinary; Salmonella/*drug effects; Salmonella Infections, Animal/*drug therapy/transmission
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Bond III, E. U., Walker, B. A., Hutt, M. D., & Reingen, P. H. (2004). Reputational Effectiveness in Cross-Functional Working Relationships. ‎J. Prod. Innov. Manag., 21(1), 44–60.
Abstract: The work of innovation management involves cross-functional coordination among specialists and managers with different work orientations, time horizons, professional backgrounds, and values (Ford and Randolph, 1992). While strong connections across functions are critical for new product development success (Green et al., 2000), some managers may be more adept at fostering effective cross-functional relationships than others. In this article, the authors empirically examine the factors that distinguish reputationally effective innovation workers from their less effective peers. Drawing on the work of Tsui (1984, 1994), reputational effectiveness is defined as the degree to which a manager has been responsive to the needs and expectations of constituents. This research examines the relational skills and interaction patterns of more (versus less) reputationally effective managers. A large business unit of a Fortune 500 telecommunications firm provided the context for our study. Using a two-phase approach, the authors first captured the social network patterns of 268 managers from marketing, research and development (R&D), manufacturing, and other business functions that were involved in the new product development process. In addition, the reputational effectiveness of each person who was identified as a member of the network was measured. In the second phase, the authors examined the relational competencies (e.g., role-taking ability, interpersonal control, openness) of the managers who participated in Phase I of the research. As predicted, the results indicate that role-taking ability is related positively to a manager's reputational effectiveness. No support, however, was found for the relationship between interpersonal control and reputational effectiveness. Interestingly, the authors found evidence of an inverse relationship between openness and effectiveness. By sharing too much information?or alternatively information that does not relate to the task at hand?the reputational effectiveness of a manager is damaged. Importantly, the results reveal that the social network characteristics of a reputationally effective manager differ from those of less effective managers. Closeness centrality, a measure of the degree of access one has to other organizational members, was associated strongly with reputational effectiveness. The results demonstrate that managers who are successful in working across functions appreciate the cognitive and emotional perspectives of diverse constituents and develop relationship ties that provide them with ready access to others across the organization.
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