Tufts University

About: Tufts University is a education organization based out in Medford, Massachusetts, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 32800 authors who have published 66881 publications receiving 3451152 citations. The organization is also known as: Tufts College & Universitatis Tuftensis.

Evaluation of networks of randomized trials.

Abstract: Randomized trials may be designed and interpreted as single experiments or they may be seen in the context of other similar or relevant evidence. The amount and complexity of available randomized evidence vary for different topics. Systematic reviews may be useful in identifying gaps in the existing randomized evidence, pointing to discrepancies between trials, and planning future trials. A new, promising, but also very much debated extension of systematic reviews, mixed treatment comparison (MTC) meta-analysis, has become increasingly popular recently. MTC meta-analysis may have value in interpreting the available randomized evidence from networks of trials and can rank many different treatments, going beyond focusing on simple pairwise-comparisons. Nevertheless, the evaluation of networks also presents special challenges and caveats. In this article, we review the statistical methodology for MTC meta-analysis. We discuss the concept of inconsistency and methods that have been proposed to evaluate it as well as the methodological gaps that remain. We introduce the concepts of network geometry and asymmetry, and propose metrics for the evaluation of the asymmetry. Finally, we discuss the implications of inconsistency, network geometry and asymmetry in informing the planning of future trials.

The akr thymic antigen and its distribution in leukemias and nervous tissues

Abstract: A clear-cut serological differentiation between AKR lymphocytes of thymic and non-thymic origin is reported: these two cell types are antigenically distinct. In newborn mice, the AKR thymic antigen was found at a high concentration only in thymus. In adult mice, the antigen was present at a high level in thymus, all nervous tissues tested, and some leukemias. It was present at much lower levels in lymph node lymphocytes, splenic lymphocytes, appendix, lung, and certain other leukemias, which appeared to be of non-thymic origin. The AKR thymic antigen was present at a high level in thymus and nervous tissues of RF mice, but was absent from thymocytes of sixteen other mouse strains. These sixteen strains possessed the C3HeB/Fe thymic antigen. The distribution of this antigen in neonatal and adult tissues of the strains tested was similar to that of the AKR thymic antigen in AKR mice. No exceptions were found. These results were obtained by use of immune cytolysis, and of a new method for the quantitative treatment of data from absorption experiments.

Bacterial small-molecule signaling pathways.

Abstract: Bacteria use diverse small molecules for extra- and intracellular signaling. They scan small-molecule mixtures to access information about both their extracellular environment and their intracellular physiological status, and based on this information, they continuously interpret their circumstances and react rapidly to changes. Bacteria must integrate extra- and intracellular signaling information to mount appropriate responses to changes in their environment. We review recent research into two fundamental bacterial small-molecule signaling pathways: extracellular quorum-sensing signaling and intracellular cyclic dinucleotide signaling. We suggest how these two pathways may converge to control complex processes including multicellularity, biofilm formation, and virulence. We also outline new questions that have arisen from recent studies in these fields.

Intentional systems in cognitive ethology: The 'panglossian paradigm' defended

Abstract: Ethologists and others studying animal behavior in a “cognitive” spirit are in need of a descriptive language and method that are neither anachronistically bound by behaviorist scruples nor prematurely committed to particular “information-processing models.” Just such an interim descriptive method can be found in intentional system theory. The use of intentional system theory is illustrated with the case of the apparently communicative behavior of vervet monkeys. A way of using the theory to generate data - including usable, testable “anecdotal” data - is sketched. The underlying assumptions of this approach can be seen to ally it directly with “adaptationist” theorizing in evolutionary biology, which has recently come under attack from Stephen Gould and Richard Lewontin, who castigate it as the “Panglossian paradigm.” Their arguments, which are strongly analogous to B. F, Skinner's arguments against “mentalism,” point to certain pitfalls that attend the careless exercise of such “Panglossian” thinking (and rival varieties of thinking as well), but do not constitute a fundamental objection to either adaptationist theorizing or its cousin, intentional system theory.