SciCombinator

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This paper investigates the case of enzyme classification to evaluate different ideals for regulating values in science. I show that epistemic and non-epistemic considerations are inevitably and untraceably entangled in enzyme classification, and argue that this has significant implications for the two main kinds of views on values in science, namely, Epistemic Priority Views and Joint Satisfaction Views. More precisely, I argue that the case of enzyme classification poses a problem for the usability and descriptive accuracy of these two views. The paper ends by suggesting that these two views provide different but complementary perspectives, and that both are useful for evaluating values in science.

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In climate science, climate models are one of the main tools for understanding phenomena. Here, we develop a framework to assess the fitness of a climate model for providing understanding. The framework is based on three dimensions: representational accuracy, representational depth, and graspability. We show that this framework does justice to the intuition that classical process-based climate models give understanding of phenomena. While simple climate models are characterized by a larger graspability, state-of-the-art models have a higher representational accuracy and representational depth. We then compare the fitness-for-providing understanding of process-based to data-driven models that are built with machine learning. We show that at first glance, data-driven models seem either unnecessary or inadequate for understanding. However, a case study from atmospheric research demonstrates that this is a false dilemma. Data-driven models can be useful tools for understanding, specifically for phenomena for which scientists can argue from the coherence of the models with background knowledge to their representational accuracy and for which the model complexity can be reduced such that they are graspable to a satisfactory extent.

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The fragmentation of academic disciplines forces individuals to specialise. In doing so, they become experts over their narrow area of research. However, ambitious scientific projects, such as the search for gravitational waves, require them to come together and collaborate across disciplinary borders. How should scientists with expertise in different disciplines treat each others' expert claims? An intuitive answer is that the collaboration should defer to the opinions of experts. In this paper we show that under certain seemingly innocuous assumptions, this intuitive answer gives rise to an impossibility result when it comes to aggregating the beliefs of experts to deliver the beliefs of a collaboration as a whole. We then argue that when experts' beliefs come into conflict, they should waive their expert status.

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A pessimistic strain of thought is fomenting in the health studies literature regarding the status of medicine. Ioannidis’s (2005) now famous finding that “most published research findings are false” and Stegenga’s (2018) book-length argument for medical nihilism are examples of this. In this paper, we argue that these positions are incorrect insofar as they rest on an untenable account of the nature of facts. Proper attention to fallibilism and the social organization of knowledge, as well as Bayesian probabilities in medical reasoning, prompt us to ask why the cynics expect the results of quantitative studies to be incontrovertibly true in the first place. While we agree with Ioannidis and others' identified flaws in the medical research enterprise, and encourage rectification, we conclude that medical nihilism is not the natural outcome of the current state of research.

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Examining tensions between the past and present uses of scientific concepts can help clarify their contributions as tools in experimental practices. This point can be illustrated by considering the concepts of mental imagery and hallucinations: despite debates over their respective referential reliabilities remaining unresolved within their interdependent histories, both are used as independently stable concepts in neuroimaging experiments. Building on an account of how these concepts function as tools structured for pursuit of diverging goals in experiments, this paper explores this tension by re-examining the continued reliance of each concept on inverse characterisations inherited from the nominally-discarded ‘mediator-view’ of sensory-like mental phenomena (SLMP). In doing so, I seek to demonstrate how examining unresolved tensions can help highlight that entrenched associations can remain both integral to, and obscured by, the uses of concepts as goal-directed tools within experimental practices.

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C. D. Broad famously labelled the problem of providing our inductive practices with a proper justification “the scandal of philosophy” (Broad, 1952). Recently, John Norton has provided a dissolution of this problem (2014). According to Norton, inductive inference is grounded in particular facts obtaining within particular domains (J. Norton, 2003b, 2010, 2014). Because the material theory does not involve a universal schema of induction, Norton claims it dissolves the problem of induction (which implies that such universal schemas cannot be justified). In this paper, I critically evaluate Norton’s dissolution. In particular, I argue that the problem of induction is an epistemological problem, that Norton’s material theory entails an externalist epistemology, and that it is a common feature of such epistemologies that they dissolve the problem of induction. The upshot is that the material theory is not unique in its ability to reap the specifically epistemic benefits of dissolving the problem of induction, and thus that the epistemic advantages of the material theory over extant alternatives in this regard are fewer than it may appear at first sight.

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Not applicable.

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Preterm birth is a serious global health problem that affects 5-18% of pregnancies worldwide. In addition to being the major cause of neonatal mortality and morbidity, preterm birth is associated with short term and long term complications in the offspring. Despite this, the causes and pathogenesis of preterm birth remain unclear. Neutrophils are innate immune cells that infiltrate the maternal-fetal interface during normal parturition and their accumulation is dramatically increased during preterm birth, especially in the presence of an infection. Indeed, a defining feature of chorioamnionitis (inflammation of the chorioamnionic fetal membranes) that is associated with more than 40% of preterm births, is neutrophil accumulation. While these cells may play an important role during normal term parturition as well as preterm birth, their functions at the maternal-fetal interface are unclear. This review will provide a broad overview of the relevant studies to enable a better understanding of the roles of neutrophils during normal parturition and preterm birth.

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Development of the placenta must always be in advance of that of the embryo. Evidence from domestic species demonstrates that the placenta is capable of stimulating its own development through a signalling dialogue with the endometrial glands. Placental lactogens produced by the trophoblast lead to increased expression and release of uterine secretions and mitogenic growth factors, including epidermal growth factor, that have a close temporal and spatial relationship with trophoblast proliferation. Here, we review evidence that an equivalent mechanism operates in the human. The same repertoire of receptors is present on the endometrial gland cells, and the epithelial cells have long been known to adopt a hypersecretory phenotype following an implantation. Furthermore, early pregnancy hormones stimulate the secretion of glycodelin-A and osteopontin, two ‘uterine milk proteins’ that have multiple potential effects at the maternal-placental interface, from organoid cultures derived from endometrial glands. Prolactin appears to be an important stimulant, but unlike in domestic species the human trophoblast does not secrete this hormone. Instead, it is a major product of decidual cells. Hence, complications of pregnancy that have their pathophysiological roots in deficient trophoblast proliferation may be due primarily to problems of decidualisation. Ensuring the endometrium is in an optimal state pre-conceptionally should therefore be a priority for women’s health. Trophoblast stemness and proliferative capacity show a sharp decline at the switch from histotrophic to haemotrophic nutrition. This may reflect the increase in oxygen concentration or loss of growth factor support. Either way, there are implications for adaptive growth of the organ.

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A complex network composed of at least 1900 microRNA (miRNA) species orchestrates the development and function of the human placenta. These molecules regulate genes and pathways operating major functional processes in trophoblast cells such as proliferation, invasion, differentiation, and metabolism. Nevertheless, the cellular localization and role of most placental miRNAs remain to be determined. The existence of eutherian- (C14MC) and primate-specific miRNA clusters (C19MC), together with human placenta-specific miRNAs, indicate the relevance of these molecules in evolution and diversification of the placenta, including the acquisition of its unique features in humans. They may be related also to diseases that are exclusively present in primates, such as preeclampsia. Changes in the miRNA expression profile have been reported in several placental pathologies. Which miRNAs are involved in the pathomechanism of these diseases or act to maintain placental homeostasis is uncertain. Placenta-derived miRNAs are packed into extracellular vesicles (EVs) and distributed through the maternal circulation to distant organs, where they contribute to adaptations required during pregnancy. Similarly, the placenta also receives molecular information from other tissues to adapt fetoplacental metabolic demands to the maternal energetic supply. These processes can be impaired in pathologic conditions. Therefore, the collection of circulating placental miRNAs constitutes potentially a minimally-invasive approach to assess the fetoplacental status and to diagnose pregnancy diseases. Future therapies may include manipulation of miRNA levels for prevention and treatment of placental complications to protect maternal health and fetal development.