Graphical AbstractScience and technology consortia provide a viable solution for the recent unsustainable academic growth in biomedical research.

Alternatives to convenience sampling (CS) are needed for HIV/STI surveillance of most-at-risk populations in Latin America. We compared CS, time space sampling (TSS), and respondent driven sampling (RDS) for recruitment of men who have sex with men (MSM) and transgender women (TW) in Lima, Peru. During concurrent 60-day periods from June-August, 2011, we recruited MSM/TW for epidemiologic surveillance using CS, TSS, and RDS. A total of 748 participants were recruited through CS, 233 through TSS, and 127 through RDS. The TSS (...) sample included the largest proportion of TW (30.7 %) and the lowest percentage of subjects who had previously participated in HIV/STI research (14.9 %). The prevalence of newly diagnosed HIV infection, according to participants' self-reported previous HIV diagnosis, was highest among TSS recruits (17.9 %) compared with RDS (12.6 %) and CS (10.2 %). TSS identified diverse populations of MSM/TW with higher prevalences of HIV/STIs not accessed by other methods. (shrink)

The meta-problem of consciousness (Chalmers, 2018) is the problem of explaining the behaviours and verbal reports that we associate with the so-called 'hard problem of consciousness'. These may include reports of puzzlement, of the attractiveness of dualism, of explanatory gaps, and the like. We present and defend a solution to the meta-problem. Our solution takes as its starting point the emerging picture of the brain as a hierarchical inference engine. We show why such a device, operating under familiar forms of (...) adaptive pressure, may come to represent some of its mid-level inferences as especially certain. These mid-level states confidently re-code raw sensory stimulation in ways that (they are able to realize) fall short of fully determining how properties and states of affairs are arranged in the distal world. This drives a wedge between experience and the world. Advanced agents then represent these mid-level inferences as irreducibly special, becoming increasingly puzzled as a result. (shrink)

The occurrence of oscillatory behaviours in living cells can be viewed as a visible consequence of stable, regulatory homeostatic cycles. Therefore, they may be used as experimental windows on the underlying physiological mechanisms. Recent studies show that growing pollen tubes are an excellent biological model for these purposes. They unite experimental simplicity with clear oscillatory patterns of both structural and temporal features, most being measurable during real‐time in live cells. There is evidence that these cellular oscillators involve an integrated input (...) of plasma membrane ion fluxes, and a cytosolic choreography of protons, calcium and, most likely, potassium and chloride. In turn, these can create positive feedback regulation loops that are able to generate and self‐sustain a number of spatial and temporal patterns. Other features, including cell wall assembly and rheology, turgor, and the cytoskeleton, play important roles and are targets or modulators of ion dynamics. Many of these features have similarities with other cell types, notably with apical‐growing cells. Pollen tubes may thus serve as a powerful model for exploring the basis of cell growth and morphogenesis. BioEssays 23:86–94, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

In Empirical Realism David K. Clark asks, simply: is there a moral structure to the universe?

Medium- and high-spin states of Pr-134 were populated using the Cd-116(Na-23, 5n) reaction and studied with the GAMMASPHERE spectrometer. Several new bands have been found in this nucleus, one of them being linked to the previously observed chiral-candidate twin-band structure. The ground state of Pr-134 could be determined through establishing a level structure that connects the two previously known long-lived isomeric states. Unambiguous spin-parity assignments for the excited states could be performed based on the known 2(-) spin-parity of the ground (...) state combined with the present experimental data. Intrinsic single-particle configurations have been assigned to the newly observed bands on the basis of the measured B(M1)/B(E2) ratios, alignments, band-crossing frequencies, bandhead spins, the observed single-particle configurations in the neighboring nuclei, and taking into account the predictions of total Routhian surface and tilted-axis cranking calculations. (shrink)

Bioethicists in healthcare institutions have the skills and insights and can and must facilitate and promote measures that address deeply ingrained structural issues that exacerbate health inequity...

What is it to be morally responsible for something? Recent philosophical work reveals considerable disagreement on the question. Indeed, some theorists claim to distinguish several varieties of moral responsibility, with different conditions that must be satisfied if one is to bear responsibility of one or another of these kinds. -/- Debate on this point turns partly on disagreement about the kinds of responses made appropriate when one is blameworthy or praiseworthy. It is generally agreed that these include "reactive attitudes" such (...) as resentment and gratitude, but theorists disagree about the nature of these attitudes. They dispute the connections between moral responsibility, desert, and the justification of punishment as well. -/- Many theorists take it that, whatever the appropriate responses are, they are responses to an agent's "quality of will," but there is no consensus on what this comes to. Are the agent's beliefs about the moral status of her behavior what matter, or is it what she cares about, or what she judges important? -/- This volume presents twelve original essays from participants in these debates. The contributors include prominent established figures as well as influential younger philosophers. A substantive introduction by the editors surveys recent debates and situates the contributions within it. (shrink)

Dominant food systems, based on industrial methods and corporate control, are in a state of flux. To enable the transition towards more sustainable and just food systems, food movements are claiming new roles in governance. These movements, and the initiatives they spearhead, are associated with a range of labels (e.g., food sovereignty, food justice, and community food security) and use a variety of strategies to enact change. In this paper, we use the concept of relational fields to conduct a post-hoc (...) analysis of nine cases, examining how social movement organizations and other actors actively create new deliberative governance spaces. We argue that successes are related to the “power to convene,” a process-oriented approach that increases movements’ capacity to mobilize; leverage different types of power; and integrate, coordinate, and build a systems-oriented vision. The power to convene and create deliberative spaces is demonstrated in a variety of contexts and often results in outcomes that further movement aims, including policy change and repositioning food movement actors vis-à-vis others in the field. Our findings suggest that success is not only measured as policy outcomes, but as an advantageous repositioning of social movement actors that enables them to be part of governance processes beyond simple policy advocacy. (shrink)

Philosophical theories of agency have focused primarily on actions and activities. But, besides acting, we often omit to do or refrain from doing certain things. How is this aspect of our agency to be conceived? This book offers a comprehensive account of omitting and refraining, addressing issues ranging from the nature of agency and moral responsibility to the metaphysics of absences and causation. Topics addressed include the role of intention in intentional omission, the connection between negligence and omission, the distinction (...) between doing and allowing, and the distinction in law between act and omission. (shrink)

In referendum elections, voters are often required to register simultaneous votes on multiple proposals. The separability problem occurs when a voter’s preferred outcome on one proposal depends on the outcomes of other proposals. This type of interdependence can lead to unsatisfactory or even paradoxical election outcomes, such as a winning outcome that is the last choice of every voter. Here we propose an iterative voting scheme that allows voters to revise their voting strategies based on the outcomes of previous iterations. (...) Using a robust computer simulation, we investigate the potential of this approach to solve the separability problem. (shrink)

As demand for locally grown food increases there have been calls to ‘scale-up’ local food production to regionally distribute food and to sell into more mainstream grocery and retail venues where consumers are already shopping. Growing research and practice focusing on how to improve, expand and conceptualize regional distribution systems includes strategies such as value chain development using the Agriculture of the Middle framework. When the Ohio Food Policy Advisory Council asked how they could scale-up the distribution of Ohio fresh (...) fruits and vegetables to Ohioans, we decided to use this practical opportunity to not only provide recommendations to this council, but to simultaneously contribute to the literature on AOTM, value-based and spatially–proximate relationships, and conceptualizations of food system hybridity. We do this while examining an entire sub-sector of the Ohio agricultural economy, namely fruit and vegetables and applying the AOTM framework beyond the farm, namely to distributors and retailers. Through interviews with Ohio retailers and a survey of all fresh fruit and vegetable distributors Ohio we: Describe current distribution systems within the state; Identify firms interested in scaling-up distribution, and; Inform state-level policy efforts by identifying opportunities to better target any state-level policy and program efforts. We demonstrate support for the concept of AOTM applied beyond the farm, for value chain development strategies that can transmit ‘quality’ via spatially proximate supply chains, and support for considering hybrid solutions, such as piggybacking for scaling-up local food systems. This work highlights the role a statewide food policy council can have in facilitating market development and their unique position to provide public sector and institutional support to facilitate meaningful connections in the food system. (shrink)

BackgroundThe ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines are widely endorsed but compliance is limited. We sought to determine whether journal-requested completion of an ARRIVE checklist improves full compliance with the guidelines.MethodsIn a randomised controlled trial, manuscripts reporting in vivo animal research submitted to PLOS ONE (March–June 2015) were randomly allocated to either requested completion of an ARRIVE checklist or current standard practice. Authors, academic editors, and peer reviewers were blinded to group allocation. Trained reviewers performed outcome adjudication (...) in duplicate by assessing manuscripts against an operationalised version of the ARRIVE guidelines that consists 108 items. Our primary outcome was the between-group differences in the proportion of manuscripts meeting all ARRIVE guideline checklist subitems.ResultsWe randomised 1689 manuscripts (control: n = 844, intervention: n = 845), of which 1269 were sent for peer review and 762 (control: n = 340; intervention: n = 332) accepted for publication. No manuscript in either group achieved full compliance with the ARRIVE checklist. Details of animal husbandry (ARRIVE subitem 9b) was the only subitem to show improvements in reporting, with the proportion of compliant manuscripts rising from 52.1 to 74.1% (X2 = 34.0, df = 1, p = 2.1 × 10−7) in the control and intervention groups, respectively.ConclusionsThese results suggest that altering the editorial process to include requests for a completed ARRIVE checklist is not enough to improve compliance with the ARRIVE guidelines. Other approaches, such as more stringent editorial policies or a targeted approach on key quality items, may promote improvements in reporting. (shrink)

Postmodern view of Australian multiculturalism. Discusses the ways in which identity and imagery merge and interact in a multicultural society, within a postmodern theoretical framework, and examines topics such as liberalism and multiculturalism, and cultural postmodernity. Includes chapter notes, a bibliography and an index. Clark is director of the Institute of Ethics and Public Policy at Monash University, Forbes is professor of geography at Flinders University of South Australia, and Francis is a postgraduate student at Monash University. The contributors (...) include sociologists, literary theorists, geographers and a philosopher. (shrink)

High-spin states in the odd-odd N = Z nucleus Co-54 have been investigated by the fusion-evaporation reaction Si-28(S-32,1 alpha 1p1n)Co-54. Gamma-ray information gathered with the Ge detector array Gammasphere was correlated with evaporated particles detected in the charged particle detector system Microball and a 1 pi neutron detector array. A significantly extended excitation scheme of Co-54 is presented, which includes a candidate for the isospin T = 1, 6(+) state of the 1f(7/2)(-2) multiplet. The results are compared to large-scale shell-model (...) calculations in the fp shell. Effective interactions with and without isospin-breaking terms have been used to probe isospin symmetry and isospin mixing. A quest for deformed high-spin rotational cascades proved negative. This feature is discussed by means of cranking calculations. (shrink)

This article argues that the goals of agricultural research in poor countries have changed substantially over the last four decades. In particular they have broadened from the early (and narrow) emphasis on food production to a much wider agenda that includes poverty alleviation, environmental degradation, and social inclusion. Conversely, agricultural research systems have proved remarkably resistant to the concomitant need for changes in research focus. As a result many, at both the national and international level, are under great strain. In (...) terms of public policy the article goes on to suggest that shortcomings of existing conceptual approaches to technology development could be supplemented by adopting analytical principles that view innovation in systemic terms. An approach where flows of knowledge between institutional nodes is a key to innovative performance (the “National Systems of Innovation” approach) is suggested as one such conceptual framework that might help supplement conventional policy analysis. (shrink)

High-spin states have been studied in Pr-135(59), populated through the Cd-116(Na-23,4n) reaction at 115 MeV, using the Gammasphere gamma-ray spectrometer. The negative-parity yrast band has been significantly extended to spin similar to 45 (h) over bar and excitation energy 21.5 MeV, showing evidence for several rotational alignments. The positive-parity yrast band of Ce-135(58), populated through the p4n channel of this reaction, was also populated to spin similar to 38 (h) over bar and excitation energy 18 MeV. Cranking calculations indicate that (...) these nuclei are soft with respect to the triaxiality parameter gamma and that several competing nuclear shapes occur at high spin. (shrink)

We take up the challenge of developing an international network with capacity to survey the world's scientists on an ongoing basis, providing rich datasets regarding the opinions of scientists and scientific sub-communities, both at a time and also over time. The novel methodology employed sees local coordinators, at each institution in the network, sending survey invitation emails internally to scientists at their home institution. The emails link to a ‘10 second survey’, where the participant is presented with a single statement (...) to consider, and a standard five point Likert scale. In June 2023, a group of 30 philosophers and social scientists invited 20,085 scientists across 30 institutions in 12 countries to participate, gathering 6,807 responses to the statement 'Science has put it beyond reasonable doubt that COVID-19 is caused by a virus'. The study demonstrates that it is possible to establish a global network to quickly ascertain scientific opinion on a large international scale, with high response rate, low opt-out rate, and in a way that allows for significant (perhaps indefinite) repeatability. Measuring scientific opinion in this new way would be a valuable complement to currently available approaches, potentially informing policy decisions and public understanding across diverse fields. (shrink)

Throughout the biological and biomedical sciences there is a growing need for, prescriptive ‘minimum information’ (MI) checklists specifying the key information to include when reporting experimental results are beginning to find favor with experimentalists, analysts, publishers and funders alike. Such checklists aim to ensure that methods, data, analyses and results are described to a level sufficient to support the unambiguous interpretation, sophisticated search, reanalysis and experimental corroboration and reuse of data sets, facilitating the extraction of maximum value from data sets (...) them. However, such ‘minimum information’ MI checklists are usually developed independently by groups working within representatives of particular biologically- or technologically-delineated domains. Consequently, an overview of the full range of checklists can be difficult to establish without intensive searching, and even tracking thetheir individual evolution of single checklists may be a non-trivial exercise. Checklists are also inevitably partially redundant when measured one against another, and where they overlap is far from straightforward. Furthermore, conflicts in scope and arbitrary decisions on wording and sub-structuring make integration difficult. This presents inhibit their use in combination. Overall, these issues present significant difficulties for the users of checklists, especially those in areas such as systems biology, who routinely combine information from multiple biological domains and technology platforms. To address all of the above, we present MIBBI (Minimum Information for Biological and Biomedical Investigations); a web-based communal resource for such checklists, designed to act as a ‘one-stop shop’ for those exploring the range of extant checklist projects, and to foster collaborative, integrative development and ultimately promote gradual integration of checklists. (shrink)

We take up the challenge of developing an international network with capacity to survey the world’s scientists on an ongoing basis, providing rich datasets regarding the opinions of scientists and scientific sub-communities, both at a time and also over time. The novel methodology employed sees local coordinators, at each institution in the network, sending survey invitation emails internally to scientists at their home institution. The emails link to a ‘10 second survey’, where the participant is presented with a single statement (...) to consider, and a standard five-point Likert scale. In June 2023, a group of 30 philosophers and social scientists invited 20,085 scientists across 30 institutions in 12 countries to participate, gathering 6,807 responses to the statement Science has put it beyond reasonable doubt that COVID-19 is caused by a virus. The study demonstrates that it is possible to establish a global network to quickly ascertain scientific opinion on a large international scale, with high response rate, low opt-out rate, and in a way that allows for significant (perhaps indefinite) repeatability. Measuring scientific opinion in this new way would be a valuable complement to currently available approaches, potentially informing policy decisions and public understanding across diverse fields. (shrink)

We take up the challenge of developing an international network with capacity to survey the world’s scientists on an ongoing basis, providing rich datasets regarding the opinions of scientists and scientific sub-communities, both at a time and also over time. The novel methodology employed sees local coordinators, at each institution in the network, sending survey invitation emails internally to scientists at their home institution. The emails link to a ‘10 second survey’, where the participant is presented with a single statement (...) to consider, and a standard five-point Likert scale. In June 2023, a group of 30 philosophers and social scientists invited 20,085 scientists across 30 institutions in 12 countries to participate, gathering 6,807 responses to the statement Science has put it beyond reasonable doubt that COVID-19 is caused by a virus. The study demonstrates that it is possible to establish a global network to quickly ascertain scientific opinion on a large international scale, with high response rate, low opt-out rate, and in a way that allows for significant (perhaps indefinite) repeatability. Measuring scientific opinion in this new way would be a valuable complement to currently available approaches, potentially informing policy decisions and public understanding across diverse fields. (shrink)

Galvanic vestibular stimulation is a non-invasive method of electrically stimulating the vestibular system. We investigated whether the application of GVS can alter the learning of new functional mobility and manual control tasks and whether learning can be retained following GVS application. In a between-subjects experiment design, 36 healthy subjects performed repeated trials, capturing the learning of either a functional mobility task, navigating an obstacle course on a compliant surface with degraded visual cues or a manual control task, using a joystick (...) to null self-roll tilt against a pseudo-random disturbance while seated in the dark. In the “learning” phase of trials, bilateral, bipolar GVS was applied continuously. The GVS waveform also differed between subjects in each task group: white noisy galvanic vestibular stimulation at 0.3 mA high-level random GVS at 0.7 mA, or with the absence of stimulation. Following the “learning” trials, all subjects were blindly transitioned to sham GVS, upon which they immediately completed another series of trials to assess any aftereffects. In the functional mobility task, we found nGVS significantly improved task learning. Further, improvements in learning the functional mobility task with nGVS were retained, even once the GVS application was stopped. The benefits in learning with nGVS were not observed in the manual control task. High level GVS tended to inhibit learning in both tasks, but not significantly so. Even once the high-level stimulation was stopped, the impaired performance remained. Improvements in learning with nGVS may be due to increased information throughput resulting from stochastic resonance. The benefit of nGVS for functional mobility, but not manual control nulling, may be due to the multisensory, strategic, motor coordination, or spatial awareness aspects of the former task. Learning improvements with nGVS have the potential to benefit individuals who perform functional mobility tasks, such as astronauts, firefighters, high performance athletes, and soldiers. (shrink)

We propose, following Clark, that generative models also play a central role in the perception and interpretation of linguistic signals. The data explanation approach provides a rationale for the role of prediction in language processing and unifies a number of phenomena, including multiple-cue integration, adaptation effects, and cortical responses to violations of linguistic expectations.

Today the connection between "person" and the "I" is acknowledged in many respects but not always analyzed. The need to relate it to the reality of the human being has sparked the present investigation of the philosophical anthropology of four thinkers from the late ancient, medieval, and contemporary periods. Although it may seem that the question of the role of the "I" with respect to the human being hinges on the larger problem of objectivity v. subjectivity, this does not seem (...) to be the case. Many topics, however, are necessarily entailed in this investigation such as individuality and universality, soul and body, consciousness and action, substance and history, the self and the other, the metaphysical and the phenomenological, and experience and the ethical. At the end of this study we arrive at more than a grammatical use of the "I." From reflection on the contributions of Plotinus, Augustine, Aquinas, and Wojtyla, the ontological role of the "I" is identified. In doing so, one realizes that the ontological does not forsake the concrete, but penetrates it more deeply. Indeed, that was what Plotinian philosophy claimed to be doing: recognizing the richness of human reality. (shrink)

Offering a detailed study of early 20th-century essayist, poet, novelist, political campaigner, and theologian G.K. Chesterton, author Stephen R.L. Clark ...

A first year graduate student, Ann Dee Margulies, changed my research career in 1962 by challenging me to direct her in the isolation of recombination‐deficient mutants of Escherichia coli K‐12. She succeeded in isolating two mutants, which conjugated with donor strains and received the donor DNA, but could not recombine that DNA with their own chromosomes. Ann Dee showed that both mutants were much more sensitive to UV radiation than was the wild type. Furthermore, she showed that one of these (...) mutants carried a single mutation affecting both recombination and resistance. This work, published in 1965, was the first demonstration of the recA gene of E. coli. Subsequent work led to the discovery of many more recombination genes, the phenomenon of post replication‐recombination repair, the invention of the SOS hypothesis and the discovery of genes encoding proteins with similar primary structure and function in all major groups of organisms. This article honors the memory of Ann Dee. (shrink)

The contest between “Lockeian liberalism” and “classical republicanism” as explanatory frameworks for the intellectual history of the American Revolution, and therefore of the present-day United States, has been one of the longest running and most distinguished in recent U.S. historiography. It also has major implications for the history of political thought in the North Atlantic Anglophone world more widely. Yet this debate was merely suspended when it was held to have ended in an ill-defined compromise. Although some U.S. historians expressed (...) doubts and qualifications, attention in U.S. historiography moved on to other themes while leaving the initial problem unsolved. This article reopens the question; it suggests that a historicization of both these two categories is now both possible and necessary, and that their supersession will advance understanding of the Revolution. It seeks to help solve this problem by the same means that the debate began: that is, by re-establishing a link between U.S. and U.K. historiographies. (shrink)

SWORD W, CLARK AM, HEGADOREN K, BROOKS S and KINGSTON D. Nursing Inquiry 2012; 19: 51–62 The complexity of postpartum mental health and illness: a critical realist studyPostpartum depression (PPD) is a major public health issue that profoundly impacts the woman, her infant and family. Although it may be linked to hormone changes, no direct hormonal aetiology has been established. A large body of evidence implicates numerous psychosocial predictors of PPD. While a history of depression predicts about 50% of (...) cases of PPD, it remains unclear why some women with a history do not develop depression following childbirth, even taking psychosocial factors into account. The aim of this study was to identify the main mechanisms and factors associated with the presence or absence of PPD in women with a history of depression, and the presence of PPD in women without a history, using a critical realist approach. The findings indicate a number of personal and contextual factors that influence postpartum mental health and illness. In addition, and perhaps most importantly, women who did not develop depression identified goal‐oriented actions that were protective. These factors and processes did not exist in isolation and the interplay among them in influencing health was apparent. More research is needed to explore the effects of these mechanisms in different contexts. (shrink)

In Jena Hegel began his philosophical career under the auspices of Schelling’s Spinozism. His declaration of philosophical independence from Schelling, dating from publication of the Phenomenology, was a repudiation of the Spinozistic definition of the absolute as merely substance. Substance without the flux of accidents, he came to see, is nothing at all. Yet in the judgment of history Hegel’s break with Schellingian Spinozism, though clearly embarked upon, was not so clearly consummated. The struggle of monism and pluralism is no (...) longer a burning issue in philosophy, and that is perhaps why Hegel’s monism is rarely mentioned by today’s Hegel scholars. But the belief that Hegel was a one-substance monist — affirming the existence of spirit as an all-encompassing and indivisible substance — was never far from the minds of earlier interpreters. Such interpreters range from K. F. Göschel to C.E.M. Joad in “Outline of Hegel’s Philosophy: Monistic Idealism,” Chapter 15 of his Guide to Philosophy,. By failing to distinguish the absolute idealism of Hegel from that of the British idealists, Whitehead himself lent support to the monistic interpretation of Hegel when he wrote. (shrink)

Eddington, A. The decline of determinism.--Heisenberg, W. and others. Dialogue concerning science and philosophical positions.--Sinnott, E. Biology and freedom.--Nuttin, J. The unconscious and freedom.--Nagel, E. Determinism in history.--Ayer, A. J. Freedom and necessity.--Campbell, C. A. Philosophical defence of freedom.--Hare, R. M. Freedom and reason.--Dewey, J. Freedom as a problem.--Sartre, J.-P. Freedom and total responsibility.--Camus, A. Freedom and rebellion.--Rand, A. Freedom and individualism.--Thévenaz, P. Freedom and action.--Luijpen, W. A. Phenomenology of freedom.--Teilhard de Chardin, P. Cosmic freedom.--Jaspers, K. Freedom and society.--Macmurray, J. (...) Freedom in the personal nexus.--Brunner, A. Incarnation of freedom.--Ricoeur, P. Freedom as human creativity.--Finance, J. de. Freedom and existence.--Bibliography (p. 243-251). (shrink)

In light of recent emphasis on K-12 scientific modeling, it is important to understand how students’ models and beliefs about modeling shape shared classroom practices, and how, in turn, shared classroom practices influence individual students’ practices. We use co-operative action to consider the ways in which sedimented practices and artifacts become part of the substrate for students’ later actions ). Lemke :273–290, 2000) and Goodwin describe and provide illustrative examples of the accumulative nature of transformation of materials and practices. However, (...) these examples range in scale from minutes to hours, and there is less guidance about applying these perspectives to consider the transformation of practices longitudinally. In this study, we find that co-operative action is a powerful framework for analyzing classroom practices. We show that new practices rippled through the classroom along three dimensions: immediate transformation, longitudinal reuse and transformation, and transformation through interaction with other practices. These findings confirm that students’ models and practices become part of the substrate for later enactments of practice, and that these practices develop co-operatively and accumulatively within the classroom. Thus, co-operative action provides a unique lens on student progress that complements learning progressions by considering the social dimension of the development of practices. We propose that the extent to which students’ practices are able to sediment into the substrate of shared classroom practices is an important indicator of the health of the classroom as a scientific community. (shrink)