Formation of branching epithelial trees from unbranched precursors is a common process in animal organogenesis. In humans, for example, this process gives rise to the airways of the lungs, the urine‐collecting ducts of the kidneys and the excretory epithelia of the mammary, prostate and salivary glands. Branching in these different organs, and in different animal classes and phyla, is morphologically similar enough to suggest that they might use a conserved developmental programme, while being dissimilar enough not to make it obviously (...) certain that they do. In this article, I review recent discoveries about the molecular regulation of branching morphogenesis in the best‐studied systems, and present evidence for and against the idea of there being a highly conserved mechanism. Overall, I come to the tentative conclusion that key mechanisms are highly conserved, at least within vertebrates, but acknowledge that more work needs to be done before the case is proved beyond reasonable doubt. BioEssays 24:937–948, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

Since the growth cone was first described a century ago by Cajal, considerable effort has been directed towards understanding the mechanisms responsible for its guidance. Traditionally, attention has focussed on the role of adhesive molecules in determining neural development. Recently, it has become apparent that inhibitory interactions may play a crucial part in axonal navigation. A common feature of inhibition seen in three model systems (peripheral nerve segmentation, retinotectal mapping and CNS/PNS segregation) is a collapse of the motile structures of (...) the growth cone. It is increasingly clear that the identification of molecular mechanisms of inhibition, as well as those of adhesion, will be of fundamental importance to understanding neural development. (shrink)

Epithelia can be defined morphologically as tissues that line surfaces, and ultrastructurally with reference to their cells' apico‐basal polarity and possession of specific cell‐cell junctions. Defining the epithelial phenotype at a molecular level is more problematic ‐ while it is easy to name proteins (e.g. keratins) expressed by a “typical” epithelium, no known molecules are expressed by every epithelium but by no other tissues. Cells can differentiate to and from the epithelial state as part of normal development, as a response (...) to disease or when manipulated in culture. Many factors (matrix components, adhesion molecules, growth factors, transcription factors) have been identified that can trigger these transitions of phenotype in specific cases, but to date no general master regulators of the epithelial state have been found. The epithelial state may therefore be controlled by multiple regulatory genes so that there is no single molecule responsible for all of the diverse types of epithelium that exist in higher animals. (shrink)

Branching morphogenesis of epithelia is an important mechanism in mammalian development. The last decade has seen the identification of many signalling pathways and intracellular mechanisms that control epithelial branching. Tissue‐level mechanisms that space new branches out have, however, remained an unsolved problem. A recent publication by Nelson et al.1 suggests—if extrapolation from their novel and abstract culture system is valid—that branches may be spaced out by a system of mutual inhibition based on diffusion of TGFβ. Such a system would allow (...) a developing tree to arrange itself, without detailed genetic specification, by adaptive self‐organization. BioEssays 29: 205–207, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

There is now a rapidly expanding population of interlinked developmental biology databases on the World Wide Web that can be readily accessed from a desk‐top PC using programs such as Netscape or Mosaic. These databases cover popular organisms (Arabidopsis, Caenorhabditis, Drosophila, zebrafish, mouse, etc.) and include gene and protein sequences, lists of mutants, information on resources and techniques, and teaching aids. More complex are databases relating domains of gene expression to embryonic anatomy and these range from existing text‐based systems for (...) specific organs such as kidney, to a massive project under development, that will cover gene expression during the whole of mouse embryogenesis. In this brief article, we review selected examples of databases currently available, look forward to what will be available soon, and explain how to gain access to the World Wide Web. (shrink)

Much contemporary biology consists of identifying the molecular components that associate to perform biological functions, then discovering how these functions are controlled. The concept of control is key to biological understanding, at least of the physiological kind; identifying regulators of processes underpins ideas of causality and allows complicated, multicomponent systems to be summarized in relatively simple diagrams and models. Unfortunately, as this article demonstrates by drawing on published articles, there is a growing tendency for authors to claim that a molecule (...) is a ‘regulator’ of something on evidence that cannot support the conclusion. In particular, gene knockout experiments, which can demonstrate only that a molecule is necessary for a process, are all too frequently being misinterpreted as revealing regulation. This logical error threatens to blur the important distinction between regulation and mere necessity and therefore to weaken one of our strongest tools for comprehending how organisms work. (shrink)

Focusing on the body as a visual and discursive platform across public space, this book explores marginalization as a sociocultural practice and hegemonic schema. The chapters center upon physical contexts, discursive spaces, and philosophical arenas to deconstruct seemingly intrinsic connections between body and behavior, whiteness, and normativity.

Prior research shows that reasoners' confidence is poorly calibrated (Shynkaruk & Thompson, 2006). The goal of the current experiment was to increase calibration in syllogistic reasoning by training reasoners on (a) the concept of logical necessity and (b) the idea that more than one representation of the premises may be possible. Training improved accuracy and was also effective in remedying some systematic misunderstandings about the task: those in the training condition were better at estimating their overall performance than those who (...) were untrained. However, training was less successful in helping reasoners to discriminate which items are most likely to cause them difficulties. In addition we explored other variables that may affect confidence and accuracy, such as the number of models required to represent the problem and whether or not the presented conclusion was necessitated by the premises, possible given the premises, or impossible given the premises. These variables had systematically different relationships to confidence and accuracy. Thus, we propose that confidence in reasoning judgements is analogous to confidence in memory retrievals, in that they are inferentially derived from cues that are not diagnostic in terms of accuracy. (shrink)

Although widely studied in other domains, relatively little is known about the metacognitive processes that monitor and control behaviour during reasoning and decision-making. In this paper, we examined the conditions under which two fluency cues are used to monitor initial reasoning: answer fluency, or the speed with which the initial, intuitive answer is produced, and perceptual fluency, or the ease with which problems can be read. The first two experiments demonstrated that answer fluency reliably predicted Feeling of Rightness judgments to (...) conditional inferences and base rate problems, which subsequently predicted the amount of deliberate processing as measured by thinking time and answer changes; answer fluency also predicted retrospective confidence judgments. Moreover, the effect of answer fluency on reasoning was independent from the effect of perceptual fluency, establishing that these are empirically independent constructs. In five experiments with a variety of reasoning problems similar to those of Alter et al., we found no effect of perceptual fluency on FOR, retrospective confidence or accuracy; however, we did observe that participants spent more time thinking about hard to read stimuli, although this additional time did not result in answer changes. In our final two experiments, we found that perceptual disfluency increased accuracy on the CRT, but only amongst participants of high cognitive ability. As Alter et al.’s samples were gathered from prestigious universities, collectively, the data to this point suggest that perceptual fluency prompts additional processing in general, but this processing may results in higher accuracy only for the most cognitively able. (shrink)

Two studies examined the use of think aloud (TA) protocol as a means for collecting data of cognitive processes during performance in golf. In study 1, TA was employed to examine if different verbalisation (Level 2 or Level 3 TA) instructions influence performance of high and low skilled golfers. Participants performed 30 putts using TA at either Level 2, Level 3, or no verbalization condition. Although Level 3 verbalization produced a higher volume of verbal data than Level 2, TA at (...) either level 2 or 3 did not impair putting performance compared to no verbalization. Study 2 examined the congruence between data collected via TA at Level 3 and cued retrospective recall of cognitive processes during golf performance. Experienced golfers performed six holes of golf whilst engaging in Level 3 TA. After performance, three semi-structured retrospective interviews were conducted (ten minutes after performance, 24 hours after performance and 48 hours after performance). A comparison of the themes identified large discrepancies between the information reported during TA and at interview, with only 38-41% similarity in variables reported to influence decision making on each hole. Both studies suggest TA is a valuable method for recording cognitive processes of individuals during task performance. TA provides richer verbal data regarding decisions than cued retrospective recall, and TA does not negatively impact performance. (shrink)

Child sexual exploitation and abuse has grave implications for the mental health and wellbeing of children and young people. It has been linked to a wide range of difficulties which may extend into adulthood. School-based prevention programs that aim to raise awareness are popular, however, have historically lacked robust and consistent evaluation. The purpose of the present study was therefore to explore young people’s experiences of attending a school-based theater-in-education program, and the impact this had on their awareness and understanding (...) of CSEA. Four focus groups of between four to six participants each were conducted with young people from two co-educational State schools in the United Kingdom. The approach of Template Analysis was used to analyze the data, and revealed a number of themes related to the superordinate themes of “Information and Detail Delivered” and “Format and Timing.” The results suggest that participants gained new awareness and understanding of aspects related to CSEA, including other forms of exploitation, as well as how to avoid harm and what to do “if bad things happen.” Participants further reported that the theater performance/live element of the program was particularly impactful, feeling that this was delivered to them at the right time, but suggesting that younger people would also benefit from the important messages. In addition, areas for improvement were identified in terms of the delivery of the program, and the issue of victim blaming. Findings are discussed with a view to practical implications and directions for future research. (shrink)

The eight pieces constituting this Meeting Report are summaries of presentations made during a panel session at the 2011 Association for Practical and Professional Ethics (APPE) annual meeting held between March 3rd and 6th in Cincinnati. Lisa Newton organized the session and served as chair. The panel of eight consisted both of pioneers in the field and more recent arrivals. It covered a range of topics from how the field has developed to where it should be going, from identification of (...) issues needing further study to problems of training the next generation of engineers and engineering-ethics scholars. (shrink)

How epigenetic mechanisms regulate genome output and response to stimuli is a fundamental question in development and disease. Past decades have made tremendous progress in deciphering the regulatory relationships involved by correlating aggregated (epi)genomics profiles with global perturbations. However, the recent development of epigenetic editing technologies now enables researchers to move beyond inferred conclusions, towards explicit causal reasoning, through 'programing’ precise chromatin perturbations in single cells. Here, we first discuss the major unresolved questions in the epigenetics field that can be (...) addressed by programable epigenome editing, including the context‐dependent function and memory of chromatin states. We then describe the epigenetic editing toolkit focusing on CRISPR‐based technologies, and highlight its achievements, drawbacks and promise. Finally, we consider the potential future application of epigenetic editing to the study and treatment of specific disease conditions. (shrink)

Name der Zeitschrift: Semiotica Jahrgang: 2014 Heft: 202 Seiten: 41-79.

In this reply, we provide an analysis of Alter et al. response to our earlier paper. In that paper, we reported difficulty in replicating Alter, Oppenheimer, Epley, and Eyre’s main finding, namely that a sense of disfluency produced by making stimuli difficult to perceive, increased accuracy on a variety of reasoning tasks. Alter, Oppenheimer, and Epley argue that we misunderstood the meaning of accuracy on these tasks, a claim that we reject. We argue and provide evidence that the tasks were (...) not too difficult for our populations and point out that in many cases performance on our tasks was well above chance or on a par with Alter et al.’s participants. Finally, we reiterate our claim that the distinction between answer fluency and perceptual fluency is genuine, and argue that Thompson et al. provided evidence that these are distinct factors that have different downstream effects on cognitive processes. (shrink)

On July 18, 1988, workers at the Metropolitan YWCA Women's Services, a Chicago-area center designed to assist women and children who are survivors of violence and sexual assault, agreed to record in a journal their thoughts at a chosen hour during that day. Each section was written by a different worker. The purpose was to bring together separate voices, all connected through their common work with survivors to begin to understand the impact of this work on their own lives.

A basic assumption in current western medicine is that good healthcare involves informed choices. Indeed, making informed choices is not only viewed as “good practice” but a right to which each individual is entitled, a perspective only recently developed in the medical field.Moreover, in the case of ethical decisions, much of the discussion on the role of the family is cast within the autonomy paradigm of contemporary bioethics; that is, family members provide emotional support but do not make decisions for (...) the competent adult patient. The family Is uniformly viewed as an Important proxy decision maker for incompetent patients; but most bioethicists would eschew any decision-making role for the family of mentally competent adult patients. Underlying the discussion of autonomy is the basic assumption in western medicine that good healthcare Involves choices by Informed individuals. (shrink)

Community supported agriculture programs are transforming the way people relate to food and agriculture. Many researchers have considered the transformative potential of CSAs on economic, social, and environmental relations. They illustrate how participants are embedded in broader political economic transformations. The same focus, however, has not been given to CSAs’ transformative impact on individual shareholders—especially in terms of their relationship to food and health. We draw together literatures from behavioral economics, econometrics, and political ecology to evaluate the potential impacts of (...) CSA participation on food lifestyle behaviors. Using primary data drawn from a survey of four groups with distinct food acquisition environments, we compare respondents’ self-assessed food-related behaviors along three different categories: produce versus processed food consumption, food away from home consumption, and food acquisition and interest in nutrition. By documenting between-group differences, we confirm that shareholders display significant absolute differences to other groups along numerous indicators related to the above-stated categories and in general assessments of health. These differences correspond directionally to behaviors public health officials identify as correlated to beneficial health outcomes. We conclude by theorizing how the food environments delineated by a CSA exchange relationship provide unique reflexive opportunities for participants to develop diverse food-related skills and behaviors. (shrink)

An incoherent visualization is when aspects of different senses of a word are present in the same visualization. We describe and implement a new model of creating contextual coherence in the visual imagination called Coherencer, based on the SOILIE model of imagination. We show that Coherencer is able to generate scene descriptions that are more coherent than SOILIE's original approach as well as a parallel connectionist algorithm that is considered competitive in the literature on general coherence. We also show that (...) co-occurrence probabilities are a better association representation than holographic vectors and that better models of coherence improve the resulting output independent of the association type that is used. Theoretically, we show that Coherencer is consistent with other models of cognitive generation. In particular, Coherencer is a similar, but more cognitively plausible model than the C3 model of concept combination created by Costello and Keane. We show that Coherencer is also consistent with both the modal schematic indices of perceptual symbol systems theory and the amodal contextual constraints of Thagard's theory of coherence. Finally, we describe how Coherencer is consistent with contemporary research on the hippocampus, and we show evidence that the process of making a visualization coherent is serial. (shrink)

Biomedical and behavioral research is a complex, multidisciplinary, and highly varied enterprise with but a single goal: to produce and disseminate knowledge about the causes, effects, prevention, diagnosis, and treatment of human illnesses and impairments. Success requires public trust in the process. When that trust has been shaken (or worse), the response has been to establish offices to exercise oversight of the various actors and to require them to adhere to regulations that specify, with various levels of detail, what they (...) may or may not do.The two regulatory frameworks examined in this report by Barbara Bierer and Mark Barnes began separately, provoked by different scandals and abuses of public trust. (shrink)