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The design and construction of genetic systems, in silico, in vitro, or in vivo, often involve the handling of various pieces of DNA that exist in different forms across an assembly process: as a standalone "part" sequence, as an insert into a carrier vector, as a digested fragment, etc. Communication about these different forms of a part and their relationships is often confusing, however, because of a lack of standardized terms. Here, we present a systematic terminology and an associated set of practices for representing genetic parts at various stages of design, synthesis, and assembly. These practices are intended to represent any of the wide array of approaches based on embedding parts in carrier vectors, such as BioBricks or Type IIS methods (e.g., GoldenGate, MoClo, GoldenBraid, and PhytoBricks), and have been successfully used as a basis for cross-institutional coordination and software tooling in the iGEM Engineering Committee.

The question of when children understand that others have minds that can represent or misrepresent reality (i.e., possess a 'Theory of Mind') is hotly debated. This understanding plays a fundamental role in social interaction (e.g., interpreting human behavior, communicating, empathizing). Most research on this topic has relied on false belief tasks such as the 'Sally-Anne Task', because researchers have argued that it is the strongest litmus test examining one's understanding that the mind can misrepresent reality. Unfortunately, in addition to a variety of other cognitive demands this widely used measure also unnecessarily involves overcoming a bias that is especially pronounced in young children-the 'curse of knowledge' (the tendency to be biased by one's knowledge when considering less-informed perspectives). Three- to 6-year-old's (n = 230) false belief reasoning was examined across tasks that either did, or did not, require overcoming the curse of knowledge, revealing that when the curse of knowledge was removed three-year-olds were significantly better at inferring false beliefs, and as accurate as five- and six-year-olds. These findings reveal that the classic task is not specifically measuring false belief understanding. Instead, previously observed developmental changes in children's performance could be attributed to the ability to overcome the curse of knowledge. Similarly, previously observed relationships between individual differences in false belief reasoning and a variety of social outcomes could instead be the result of individual differences in the ability to overcome the curse of knowledge, highlighting the need to re-evaluate how best to interpret large bodies of research on false belief reasoning and social-emotional functioning., Competing Interests: My coauthors and I have no conflict of interest regarding the manuscript.

The ability to make inferences about what one's peers know is critical for social interaction and communication. Three experiments (n = 309) examined the curse of knowledge, the tendency to be biased by one's knowledge when reasoning about others' knowledge, in children's estimates of their peers' knowledge. Four- to 7-year-olds were taught the answers to factual questions and estimated how many peers would know the answers. When children learned familiar answers, they showed a curse of knowledge in their peer estimates. But, when children learned unfamiliar answers to the same questions, they did not show a curse of knowledge. These data shed light on the mechanisms underlying perspective taking, supporting a fluency misattribution account of the curse of knowledge., (© 2020 Society for Research in Child Development.)

Knowledge can be a curse: Once we have acquired a particular item of knowledge it tends to bias, or contaminate, our ability to reason about a less informed perspective (referred to as the 'curse of knowledge' or 'hindsight bias'). The mechanisms underlying the curse of knowledge bias are a matter of great import and debate. We highlight two mechanisms that have been proposed to underlie this bias-inhibition and fluency misattribution. Explanations that involve inhibition argue that people have difficulty fully inhibiting or suppressing the content of their knowledge when trying to reason about a less informed perspective. Explanations that involve fluency misattribution focus on the feelings of fluency with which the information comes to mind and the tendency to misattribute the subjective feelings of fluency associated with familiar items to the objective ease or foreseeability of that information. Three experiments with a total of 359 undergraduate students provide the first evidence that fluency misattribution processes are sufficient to induce the curse of knowledge bias. These results add to the literature on the many manifestations of the curse of knowledge bias and the many types of source misattributions, by revealing their role in people's judgements of how common, or widespread, one's knowledge is. The implications of these results for cognitive science and social cognition are discussed., (Copyright © 2017. Published by Elsevier B.V.)

Perspective taking, or "theory of mind," involves reasoning about the mental states of others (e.g., their intentions, desires, knowledge, beliefs) and is called upon in virtually every aspect of human interaction. Our goals in writing this chapter were to provide an overview of (a) the research questions developmental psychologists ask to shed light on how children think about the inner workings of the mind, and (b) why such research is invaluable in understanding human nature and our ability to interact with, and learn from, one another. We begin with a brief review of early research in this field that culminated in the so-called litmus test for a theory of mind (i.e., false-belief tasks). Next, we describe research with infants and young children that created a puzzle for many researchers, and briefly mention an intriguing approach researchers have used to attempt to "solve" this puzzle. We then turn to research examining children's understanding of a much broader range of mental states (beyond false beliefs). We briefly discuss the value of studying individual differences by highlighting their important implications for social well-being and ways to improve perspective taking. Next, we review work illustrating the value of capitalizing on children's proclivity for selective social learning to reveal their understanding of others' mental states. We close by highlighting one line of research that we believe will be an especially fruitful avenue for future research and serves to emphasize the complex interplay between our perspective-taking abilities and other cognitive processes., (© 2017 Elsevier Inc. All rights reserved.)

Today's children have more opportunities than ever before to learn from interactive technology, yet experimental research assessing the efficacy of children's learning from interactive media in comparison to traditional learning approaches is still quite scarce. Moreover, little work has examined the efficacy of using touch-screen devices for research purposes. The current study compared children's rate of learning factual information about animals during a face-to-face instruction from an adult female researcher versus an analogous instruction from an interactive device. Eighty-six children ages 4 through 8 years (64% male) completed the learning task in either the Face-to-Face condition ( n = 43) or the Interactive Media condition ( n = 43). In the Learning Phase of the experiment, which was presented as a game, children were taught novel facts about animals without being told that their memory of the facts would be tested. The facts were taught to the children either by an adult female researcher (Face-to-Face condition) or from a pre-recorded female voice represented by a cartoon Llama (Interactive Media condition). In the Testing Phase of the experiment that immediately followed, children's memory for the taught facts was tested using a 4-option forced-choice paradigm. Children's rate of learning was significantly above chance in both conditions and a comparison of the rates of learning across the two conditions revealed no significant differences. Learning significantly improved from age 4 to age 8, however, even the preschool-aged children performed significantly above chance, and their performance did not differ between conditions. These results suggest that, interactive media can be equally as effective as one-on-one instruction, at least under certain conditions. Moreover, these results offer support for the validity of using interactive technology to collect data for research purposes. We discuss the implications of these results for children's learning from interactive media, parental attitudes about interactive technology, and research methods.

Understanding the factors that affect efficiency of manganese oxides as water oxidation catalysts is an essential step toward developing commercially viable electrocatalysts. It is important to understand the performance of the smallest versions of these catalysts, which will in return be advantageous with bottom up catalytic design. Density functional theory calculations have been employed to investigate water oxidation processes on Mn2(μ-OH)(μ-O)(H2O)3(OH)5 (Mn2O4·6H2O), Mn2(μ-OH)2(H2O)3(OH)4 (Mn2O3·6H2O), and Mn2(μ-OH)2(H2O)4(OH)4 (Mn2O3·7H2O) complexes. The effect of different oxidation states of manganese is considered in this study. Thermodynamically, the lowest energy pathway for the fully saturated Mn2O4·6H2O complex occurs through a nucleophilic attack of a solvent water molecule to a Mn(IV1/2)O oxo moiety. The lowest energy pathway on the Mn2O3·6H2O complex proceeds with an attack of Mn(VI)O group to the surface hydroxo group on the same manganese atom; this pathway is related to the third lowest energy pathway on the Mn2O4·6H2O complex. The water oxidation process on the fully saturated Mn2O3·7H2O complex also involves a nucleophilic attack from a solvent water molecule to a Mn(V)O moiety. The formation of these manganese oxo groups can be used as a descriptor for selecting a manganese-based water splitting catalyst due to the high electrochemical potentials required for the generation of these groups.

Molecular biologists routinely clone genetic constructs from DNA segments and formulate plans to assemble them. However, manual assembly planning is complex, error prone and not scalable. We address this problem with an algorithm-driven DNA assembly planning software tool suite called Raven (http://www.ravencad.org/) that produces optimized assembly plans and allows users to apply experimental outcomes to redesign assembly plans interactively. We used Raven to calculate assembly plans for thousands of variants of five types of genetic constructs, as well as hundreds of constructs of variable size and complexity from the literature. Finally, we experimentally validated a subset of these assembly plans by reconstructing four recombinase-based 'genetic counter' constructs and two 'repressilator' constructs. We demonstrate that Raven's solutions are significantly better than unoptimized solutions at small and large scales and that Raven's assembly instructions are experimentally valid.

We present a workflow for the design and production of biological networks from high-level program specifications. The workflow is based on a sequence of intermediate models that incrementally translate high-level specifications into DNA samples that implement them. We identify algorithms for translating between adjacent models and implement them as a set of software tools, organized into a four-stage toolchain: Specification, Compilation, Part Assignment, and Assembly. The specification stage begins with a Boolean logic computation specified in the Proto programming language. The compilation stage uses a library of network motifs and cellular platforms, also specified in Proto, to transform the program into an optimized Abstract Genetic Regulatory Network (AGRN) that implements the programmed behavior. The part assignment stage assigns DNA parts to the AGRN, drawing the parts from a database for the target cellular platform, to create a DNA sequence implementing the AGRN. Finally, the assembly stage computes an optimized assembly plan to create the DNA sequence from available part samples, yielding a protocol for producing a sample of engineered plasmids with robotics assistance. Our workflow is the first to automate the production of biological networks from a high-level program specification. Furthermore, the workflow's modular design allows the same program to be realized on different cellular platforms simply by swapping workflow configurations. We validated our workflow by specifying a small-molecule sensor-reporter program and verifying the resulting plasmids in both HEK 293 mammalian cells and in E. coli bacterial cells.

Objectives: To evaluate compliance and safety of an emergency medical service (EMS) triage protocol that allows paramedics to transport patients directly to psychiatric emergency services., Methods: A psychiatric patient diversion protocol was developed for our system. Protocol compliance was evaluated the following 3 ways: (1) psychiatric facility intake forms completed by mental health workers on patients transported by EMS directly to a psychiatric emergency service (PES) bypassing the ED, (2) hospital records for patients who were redirected from PES to the ED for medical evaluation, (3) retrospective analysis of ambulance charts. Study outcomes included protocol noncompliance rate, protocol failure rate, and any morbidity associated with either noncompliance or protocol failure. Data were analyzed using proportions and 95% confidence intervals (CI)., Results: A total of 174 patients were directly transported to PES bypassing ED medical clearance. The protocol effectively screened for medical issues in 96% of cases. Protocol noncompliance occurred in 51 cases for a frequency of 29% (CI, 22%-36%). One patient in the paramedic noncompliance group required hospital admission. There was protocol failure in 5 (2.9%; 95% CI, 0.9-6.6) of the patients who fit all protocol requirements for transport to PES but required secondary transport to the ED. All were subsequently transferred back to PES. Nine patients (5.2%; CI, 2.7%-9.5%) required secondary transfer to the ED. No patient had critical or life-threatening problems., Conclusions: Emergency medical service providers showed a poor level of compliance with vital sign criteria, but the protocol provided a high level of safety.

Purpose: To report a dramatic occlusive event of the macula surrounding the foveal avascular zone, causing severe and permanent loss of vision in a child with sickle cell disease., Methods: Case report. A nine-year-old boy with SS hemoglobinopathy and oculocutaneous albinism developed acute unilateral loss of vision., Results: Ophthalmoscopy revealed a pale, milky white, thickened retinal lesion centered on the fovea in the right eye as well as foveal hypoplasia in the left eye. The presence of macular malformation associated with oculocutaneous albinism precluded formation of a cherry-red spot. Fluorescein angiography of the right eye demonstrated extensive occlusions of the arterioles surrounding the foveal avascular zone. The presence of occlusions surrounding the fovea from multiple directions suggested the possibility of central retinal artery occlusion with migration of microemboli downstream., Conclusion: The patient, the youngest case reported, developed an irreversible macular infarction that was not improved by an exchange erythrocyte transfusion. He was placed on a long-term monthly transfusion protocol to protect his unaffected eye.

L-selectin (CD62L) is the principal leukocyte adhesion molecule for the high endothelial venules of peripheral lymph nodes. This adhesion has an absolute requirement for calcium ions. Nevertheless, some studies have shown carbohydrate adhesion receptor interactions on lymphocytes and neutrophils, including the L-selectin molecule, that are Ca-independent. In the present study fucoidan, a reportedly Ca2+ independent ligand of L-selectin, and Mabs to human CD62L were coupled to magnetic polystyrene beads (MPB), as a model of leukocyte-surface interactions, and the efficiency of human leukocyte separation was investigated. 30% of Ficoll-purified human mononuclear cells and 75% of dextran-purified human leukocytes (DPHL) were specifically bound by fucoidan-modified MPB in the presence of Ca2+; 55% of dextran-purified leukocytes were specifically bound in the absence of Ca2+. The specific binding was inhibited by an excess of free fucoidan. The data obtained show the presence of Ca-independent adhesion determinants, specific to fucoidan on human leukocytes. No significant specific binding of leukocytes to fucoidan-modified MPB was found after the incubation with fresh human Ca(2+)-depleted whole blood. More than 90% of DPHL were specifically bound to MPB modified with Mabs to human CD62L irrespective of Ca2+ presence. The same degree of separation was achieved after the incubation with fresh human Ca(2+)-depleted-whole blood with anti-CD62L modified beads.

Transparent film dressings have many of the attributes of the ideal wound dressing. However, currently available film dressings are deficient in their ability to handle varying levels of wound exudate. The permeability of polymeric films to water vapor is discussed and techniques are described to produce films in which the moisture vapor permeability is a function of the moisture in the environment. Illustrations are provided showing the variation of permeability with relative humidity and water contact. The unique properties of coextruded films are illustrated and the responsiveness of such a film dressing to varying conditions at the wound are discussed.