Social categories in the making: construction or recruitment?

Real kinds, both natural and social categories, are characterized by rich inductive potential. They have relatively stable sets of conceptually independent projectable properties. Somewhat surprisingly, even some purely social categories (e.g., ethnicity, gender, political orientation) show such multiple projectability. The article explores the origin of the inductive richness of social categories and concepts. I argue that existing philosophical accounts provide only a partial explanation, and mechanisms of boundary formation and stabilization must be brought into view for a more comprehensive account of inductively rich social categories.

Evidence for multiple sources of inductive potential: Occupations and their relations to social institutions

Several current theories have essences as primary drivers of inductive potential: e.g., people infer dogs share properties because they share essences. We investigated the possibility that people take occupational roles as having robust inductive potential because of a different source: their position in stable social institutions. In Studies 1-4, participants learned a novel property about a target, and then decided whether two new individuals had the property (one with the same occupation, one without). Participants used occupational roles to robustly generalize rights and obligations, functional behaviors, personality traits, and skills. In Studies 5-6, we contrasted occupational roles (via label) with race/gender (via visual face cues). Participants reliably favored occupational roles over gender /race for generalizing rights and obligations, functional behaviors, personality traits, and skills (they favored race/gender for inferring leisure behaviors and physiological properties). In comparison with animal categories, occupational roles supported inferences to the same extent (Studies 4 and 6). In Study 7, we examined whether a community could make discoveries about occupations embedded in the institutions they created. Participants indicated this was possible. In Study 8, we examined why members of occupational roles share properties. Participants did not attribute the inductive potential of occupational roles to essences, they attributed it to social institutions. In combination, these eight studies demonstrate that any theory of inductive potential must pluralistically allow for both essences and social institutions to form the basis of inductive potential.

Beyond Cause: The Development of Clockwork Cognition

Thinking of the world in mechanistic terms—how things work—is both cognitively natural and motivating for humans from the preschool years onward. Mechanisms have distinct structural properties that go far beyond mere causal facts. They typically contain layers of causal clusters and the systematic interactions between those clusters that give rise to the next level up. Following developments in the philosophy of science and studies on children’s questioning behaviors, recent research shows that, from an early age, people appreciate the informational and inductive potential of mechanistic information. People selectively notice and choose mechanistic explanations as especially useful opportunities for learning; but they also soon forget the details of what they encounter. We argue that enduring cognitive abstractions from such details provide powerful ways of accessing and evaluating expertise in other people.

Salivary Gland Organ Regeneration for Oral Health

Salivary glands play essential roles in normal upper gastrointestinal tract function and oral health via saliva production. There are three types of salivary glands; the submandibular gland and parotid gland, which secrete serous saliva, and the sublingual gland secretes mucous saliva in mice [1]. Therefore, salivary gland dysfunction due to atrophy of acinar cells caused by Sjogren’s syndrome, radiation therapy for head and neck cancer, and aging and saliva reduction, and results in xerostomia (dry mouth syndrome), causes various clinical problems in oral health and influences overall bodily health [2]. Xerostomia induces various clinical problems in oral health, such as dental decay, bacterial infection, and disorders of mastication and swallowing, which result in a general reduction in the quality of life [3]. Current standard to cure xerostomia are symptomatic treatments, such as the administration of artificial saliva substitutes and sialogogues, and the administration of parasympathetic stimulation drugs, including pilocarpine and cevimeline [4]. In salivary gland regenerative therapy, stem cell transplantation, which expressed c-kit and Sca-1 as stem cell markers and exhibit high proliferative capacities [5,6], and gene modification for water channel aquaporin-1 (AQP1) and Interleukin-17 (IL-17) receptor antibody is performed to restore the damaged acinar tissue and recover the flow of saliva [7,8]. Salivary glands arise from the organ germ, which is induced by reciprocal epithelial and mesenchymal stem cell interactions during embryonic development [9]. In this two decades, advances in developmental biology have led to break-through in regeneration of functional bioengineered organ in vitro by using embryonic organ-inductive potential stem cells. Recently, regeneration of fully functional salivary gland as a next-generation organ regeneration has been reported after the transplantation of bioengineered salivary gland germ developed by using embryonic organ-inductive potential stem cells as well as iPS cells [10,11]. In 2013, we demonstrated the fully functional salivary gland regeneration by recapitulating the embryonic morphogenesis. The bioengineered salivary gland organ germ, which was reconstituted by our Organ Germ Method using organ-inductive potential stem cells derived from submandibular gland germs of ED 13.5 mice [12], showed reciprocal epithelial and mesenchymal interactions in in vitro organ culture. Following the orthotopic transplantation, the bioengineered germ develops into a mature salivary gland via acinar formations with a myoepithelium and innervation. The bioengineered salivary gland produces saliva in response to the pilocarpine administration and gustatory stimulation by citrate, protected against bacterial infection and restores normal swallowing function in a mouse model. This study provides a proofof- concept for bioengineered salivary gland regeneration. The next breakthrough first reported in 2008 was the emergence of an organoid as a mini-organ that was generated by inducing body patterning and a subsequent organ-forming field formation in pluripotent stem cells [13]. Organoids are useful to recapitulate the process of organogenesis, which are strictly regulated by morphogen signalling and transcriptional networks. To date, multiple types of organoids, including the retina, pituitary gland, liver, and lung have been successfully generated in vitro. Our colleagues identified a specific combination of two transcription factors, Sox9 and Foxc1, are responsible for the differentiation of mouse ES cells-derived oral ectodermal region into the salivary gland rudiment in a threedimensional organoid culture system [11]. The induced salivary gland rudiment showed a similar morphologies and gene expression profiles to those of the embryonic salivary gland rudiment of normal mice. Following orthotopic transplantation into salivary glands-defected mice, the induced salivary gland germ exhibited characteristics of mature salivary glands including histological morphologies, nerve innervation and saliva secretion. This study is the first report of the fully functional organ regeneration by using organoid, demonstrating the potential of salivary gland organ regeneration from pluripotent stem cells for an additional organ replacement regenerative therapy. As part of regenerative medicine, the autogenous transplantation of stem cells, including bone marrow, and tissue sheets such as skin, cornea, and cardiac muscle, has already been applied clinically through cell and tissue transplantation therapies. The progress made in the past two decades has been remarkable, paving the way for possible future organ replacement regenerative therapies. There remains a critical issue as to whether next-generation organ regenerative therapy can be adopted as a novel clinical therapy for patients of the loss of organ function. The bioengineered salivary gland organ germ by using both embryonic organ-inductive potential stem cells and pluripotent stem cells can grow where salivary grand should be in oral cavity and produce the saliva in response to various taste stimulations. These works indicate the potentials for clinical application of salivary gland organ regeneration. Applying knowledge of these basic research will enable the regeneration of salivary gland organ in the next decades.

Essentializing Inferences

Predicate nominals (e.g., ‘is a female’) seem to label or categorize their subjects, while their predicate adjective correlates (e.g, ‘is female’) merely attribute a property. Further, predicate nominals elicit essentializing inferential judgments about inductive potential as well as stable explanatory membership. Semantic data and research from developmental and cognitive psychology support that this distinction is robust and productive. I argue that while the difference between predicate nominals and predicate adjectives is elided by standard semantic theories, it ought not be. I then develop and defend a psychologically motivated semantic account that takes predicate nominals to involve attributing kind membership and to trigger a presupposition that underpins our essentialist judgments.

Fabrication and Plasma Surface Activation of Aligned Electrospun PLGA Fiber Fleeces with Improved Adhesion and Infiltration of Amniotic Epithelial Stem Cells Maintaining their Teno-inductive Potential

Electrospun PLGA microfibers with adequate intrinsic physical features (fiber alignment and diameter) have been shown to boost teno-differentiation and may represent a promising solution for tendon tissue engineering. However, the hydrophobic properties of PLGA may be adjusted through specific treatments to improve cell biodisponibility. In this study, electrospun PLGA with highly aligned microfibers were cold atmospheric plasma (CAP)-treated by varying the treatment exposure time (30, 60, and 90 s) and the working distance (1.3 and 1.7 cm) and characterized by their physicochemical, mechanical and bioactive properties on ovine amniotic epithelial cells (oAECs). CAP improved the hydrophilic properties of the treated materials due to the incorporation of new oxygen polar functionalities on the microfibers’ surface especially when increasing treatment exposure time and lowering working distance. The mechanical properties, though, were affected by the treatment exposure time where the optimum performance was obtained after 60 s. Furthermore, CAP treatment did not alter oAECs’ biocompatibility and improved cell adhesion and infiltration onto the microfibers especially those treated from a distance of 1.3 cm. Moreover, teno-inductive potential of highly aligned PLGA electrospun microfibers was maintained. Indeed, cells cultured onto the untreated and CAP treated microfibers differentiated towards the tenogenic lineage expressing tenomodulin, a mature tendon marker, in their cytoplasm. In conclusion, CAP treatment on PLGA microfibers conducted at 1.3 cm working distance represent the optimum conditions to activate PLGA surface by improving their hydrophilicity and cell bio-responsiveness. Since for tendon tissue engineering purposes, both high cell adhesion and mechanical parameters are crucial, PLGA treated for 60 s at 1.3 cm was identified as the optimal construct.

Generics designate kinds but not always essences

People believe that some categories are kinds with reliable causal structure and high inductive potential (e.g., Tigers). Widely endorsed theories propose that people are biased to assume kinds are essential, and so naturally determined by internal causal properties. Generic language (e.g., “Men like sports”) is one mechanism thought to evoke this bias. We propose instead that generics principally designate that categories are kinds. Participants can entertain diverse causal structures in the presence of generics: Hearing that biological properties generalize to a category (e.g., “Men grow beards”) prompts participants to infer essential structure, but hearing neutral or social properties (“Women are underpaid”) generalize prompts other causal beliefs. Thus, generics induce essentialism only in in interaction with cues that reasonably prompt essentialist explanation. We tested our model with adult participants (N = 739 total), using measures that disentangle essentialist beliefs from kind beliefs. In Study 1, we replicate prior methods with our new measures, and find that generics influence kind beliefs more than essentialism. In Study 2, we vary property content (biological vs. cultural properties), and show that generics only increase essentialism when paired with biological properties. In Study 3, we show that generics designate kinds but not essentialism when neutral properties are used across animals, tools, and people. In Study 4, we show that believing a category is a kind increases the spontaneous production of generic statements, regardless of whether the kind is essential or socially constructed. Generics do not necessitate essentialist beliefs. Participants were flexible in their reasoning about kinds.

Generics designate kinds but not always essences

People believe that some categories are kinds with reliable causal structure and high inductive potential (e.g., tigers). Widely endorsed theories propose that people are biased to assume kinds are essential, and so naturally determined by internal causal properties. Generic language (e.g., “men like sports”) is 1 mechanism thought to evoke this bias. We propose instead that generics principally designate that categories are kinds. Participants can entertain diverse causal structures in the presence of generics: Hearing that biological properties generalize to a category (e.g., “men grow beards”) prompts participants to infer essential structure, but hearing neutral or social properties (“women are underpaid”) generalized prompts other causal beliefs. Thus, generics induce essentialism only in interaction with cues that reasonably prompt essentialist explanation. We tested our model with adult participants (n = 739 total), using measures that disentangle essentialist beliefs from kind beliefs. In study 1, we replicate prior methods with our new measures, and find that generics influence kind beliefs more than essentialism. In study 2, we vary property content (biological vs. cultural properties), and show that generics only increase essentialism when paired with biological properties. In study 3, we show that generics designate kinds but not essentialism when neutral properties are used across animals, tools, and people. In study 4, we show that believing a category is a kind increases the spontaneous production of generic statements, regardless of whether the kind is essential or socially constructed. Generics do not necessitate essentialist beliefs. Participants were flexible in their reasoning about kinds.