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Vilstrup Mead posted an update 1 day, 11 hours ago
Riemerella anatipestifer infection causes serious economic losses in the duck industry worldwide. Acute septicemia and high blood bacterial loading in R. anatipestifer infected ducks indicate that R. anatipestifer may be able to obtain iron and other nutrients by lysing duck erythrocytes to support its rapid growth and proliferation in the blood. However, so far, little is known about the hemolytic activity of R. anatipestifer to duck erythrocytes. In this study, 29 of 52 R. anatipestifer strains showed hemolytic activity on duck blood agar, whereas all the tested dba+ (with hemolytic activity on duck blood agar) and dba- strains created pores in the duck red blood cells, with 4.35-9.03% hemolytic activity in a liquid hemolysis assay after incubation for 24 h. The concentrated culture supernatants of all the tested R. anatipestifer strains and the extracted outer membrane proteins (OMPs) from dba+ R. anatipestifer strains showed hemolytic activity on duck blood agar. These results, together with the median lethal dose (LD50) of some dba+ and dba- R. anatipestifer strains in ducklings, suggested that there was no direct relationship between the hemolytic capacity of R. anatipestifer on duck blood agar and its virulence.Introduction. Streptococcus pneumoniae is responsible for many community infections, with the main ones being pneumonia and meningitis. Pneumococcus has developed increased resistance to multiple classes of antibiotics. The evolution of antibiotic resistance in pneumococcus was influenced by changes in serotype distribution under vaccine selection pressure.Aim. The aim of this study was to determine the genes involved in macrolide resistance, the antimicrobial susceptibility, the serotype distribution and the spread of international antibiotic-resistant clones among clinical isolates of S. pneumoniae.Methodology. We investigated 86 erythromycin-resistant S. pneumoniae strains isolated from respiratory (n=74) or non-respiratory (n=12) samples in Tunisia. Antimicrobial susceptibility was tested using the disk diffusion method. Macrolide-resistant strains were analysed by polymerase chain reaction (PCR) for ermA, ermB, mefA and msrD. We also investigated the macrolide resistance mechanisms in eight isolates (9.3ee global antibiotic-resistant clones were identified Denmark14 ST230, Portugal19F ST177 and Spain9V ST156.Conclusion. This study shows that macrolide resistance among S. pneumoniae isolated in Tunisia is mainly related to target site modification. Our observations demonstrate a high degree of genetic diversity and capsular types among strains resistant to macrolides.Resource rationality holds great promise as a unifying principle across theories in neuroscience, cognitive science, and economics. The target article clearly lays out this potential for unification. However, resource-rational models are more diverse and less easily unified than might appear from the target article. Here, we explore some of that diversity.We propose an alternative and unifying framework for decision-making that, by using quantum mechanics, provides more generalised cognitive and decision models with the ability to represent more information compared to classical models. This framework can accommodate and predict several cognitive biases reported in Lieder & Griffiths without heavy reliance on heuristics or on assumptions of the computational resources of the mind.We agree that combining rational analysis with cognitive bounds, what we previously introduced as Cognitively Bounded Rational Analysis, is a promising and under-used methodology in psychology. We further situate the framework in the literature, and highlight the important issue of a theory of subjective utility, which is not addressed sufficiently clearly in the framework or related previous work.Lieder and Griffiths advocate for resource-rational analysis as a methodological device employed by the experimenter. However, at times this methodological device appears to morph into the substantive claim that humans are actually resource-rational. Such morphing is problematic; the methodological approach used by the experimenter and claims about the nature of human behavior ought to be kept completely separate.Resource rationality may explain suboptimal patterns of reasoning; but what of “anti-Bayesian” effects where the mind updates in a direction opposite the one it should? We present two phenomena – belief polarization and the size-weight illusion – that are not obviously explained by performance- or resource-based constraints, nor by the authors’ brief discussion of reference repulsion. Can resource rationality accommodate them?The commentaries raised questions about normativity, human rationality, cognitive architectures, cognitive constraints, and the scope or resource rational analysis (RRA). We respond to these questions and clarify that RRA is a methodological advance that extends the scope of rational modeling to understanding cognitive processes, why they differ between people, why they change over time, and how they could be improved.Lieder and Griffiths rightly urge that computational cognitive models be constrained by resource usage, but they should go further. Tacrolimus in vitro The brain’s primary function is to regulate resource usage. As a consequence, resource usage should not simply select among algorithmic models of “aspects of cognition.” Rather, “aspects of cognition” should be understood as existing in the service of resource management.Resource rationality is useful for choosing between models with the same cognitive constraints but cannot settle fundamental disagreements about what those constraints are. We argue that sampling is an especially compelling constraint, as optimizing accumulation of evidence or hypotheses minimizes the cost of time, and there are well-established models for doing so which have had tremendous success explaining human behavior.Lieder and Griffiths present the computational framework “resource-rational analysis” to address the reverse-engineering problem in cognition. Here we discuss how developmental psychology affords a unique and critical opportunity to employ this framework, but which is overlooked in this piece. We describe how developmental change provides an avenue for ongoing work as well as inspiration for expansion of the resource-rational approach.