Advancing the Understanding of Environmental Transformations, Bioavailability and Effects of Nanomaterials, an International US Environmental Protection Agency—UK Environmental Nanoscience Initiative Joint Program.

Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United Kingdom (UK) Environmental Nanoscience Initiative and the United States (US) Environmental Protection Agency have developed an international research program to enhance the knowledgebase and develop risk-predicting models for manufactured nanoparticles. Here we report selected highlights of the program as it sought to maximize the complementary strengths of the transatlantic scientific communities by funding three integrated US-UK consortia to investigate the transformation of these nanoparticles in terrestrial, aquatic, and atmospheric environment. Research results demonstrate there is a functional relationship between the physicochemical properties of environmentally transformed nanomaterials and their effects and that this relationship is amenable to modeling. In addition, the joint transatlantic program has allowed the leveraging of additional funding, promoting transboundary scientific collaboration

IFITM3 restricts the morbidity and mortality associated with influenza

The 2009 H1N1 influenza pandemic showed the speed with which a novel respiratory virus can spread and the ability of a generally mild infection to induce severe morbidity and mortality in a subset of the population. Recent in vitro studies show that the interferon-inducible transmembrane (IFITM) protein family members potently restrict the replication of multiple pathogenic viruses1, 2, 3, 4, 5, 6, 7. Both the magnitude and breadth of the IFITM proteins’ in vitro effects suggest that they are critical for intrinsic resistance to such viruses, including influenza viruses. Using a knockout mouse model8, we now test this hypothesis directly and find that IFITM3 is essential for defending the host against influenza A virus in vivo. Mice lacking Ifitm3 display fulminant viral pneumonia when challenged with a normally low-pathogenicity influenza virus, mirroring the destruction inflicted by the highly pathogenic 1918 ‘Spanish’ influenza9, 10. Similar increased viral replication is seen in vitro, with protection rescued by the re-introduction of Ifitm3. To test the role of IFITM3 in human influenza virus infection, we assessed the IFITM3 alleles of individuals hospitalized with seasonal or pandemic influenza H1N1/09 viruses. We find that a statistically significant number of hospitalized subjects show enrichment for a minor IFITM3 allele (SNP rs12252-C) that alters a splice acceptor site, and functional assays show the minor CC genotype IFITM3 has reduced influenza virus restriction in vitro. Together these data reveal that the action of a single intrinsic immune effector, IFITM3, profoundly alters the course of influenza virus infection in mouse and human

Epistemological framing and novice elementary teachers’ approaches to learning and teaching engineering design

As engineering learning experiences increasingly begin in elementary school, elementary teacher preparation programs are an important site for the study of teacher development in engineering education. In this article, we argue that the stances that novice teachers adopt toward engineering learning and knowledge are consequential for the opportunities they create for students. We present a comparative case study examining the epistemological framing dynamics of two novice urban teachers, Ana and Ben, as they learned and taught engineering design during a four‐week institute for new elementary teachers. Although the two teachers had very similar teacher preparation backgrounds, they interpreted the purposes of engineering design learning and teaching in meaningfully different ways. During her own engineering sessions, Ana took up the goal not only of meeting the needs of the client but also of making scientific sense of artifacts that might meet those needs. When facilitating students’ engineering, she prioritized their building knowledge collaboratively about how things work. By contrast, when Ben worked on his own engineering, he took up the goal of delivering a product. When teaching engineering to students, he offered them constrained prototyping tasks to serve as hands‐on contexts for reviewing scientific explanations. These findings call for teacher educators to support teachers’ framing of engineering design as a knowledge building enterprise through explicit conversations about epistemology, apprenticeship in sense‐making strategies, and tasks intentionally designed to encourage reasoning about design artifacts.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/1/tea21541_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/2/tea21541.pd

Black Girls Speak STEM: Counterstories of Informal and Formal Learning Experiences

This study presents the interpretations and perceptions of Black girls who participated in I AM STEM – a community-based informal science, technology, engineering, and mathematics (STEM) program. Using narrative inquiry, participants generated detailed accounts of their informal and formal STEM learning experiences. Critical race methodology informed this research to portray the dynamic and complex experiences of girls of color, whose stories have historically been silenced and misrepresented. The data sources for this qualitative study included individual interviews, student reflection journals, samples of student work, and researcher memos, which were triangulated to produce six robust counterstories. Excerpts of the counterstories are presented in this article. The major findings of this research revealed that I AM STEM ignited an interest in STEM learning through field trips and direct engagement in scientific phenomena that allowed the girls to become agentic in continuing their engagement in STEM activities throughout the year. This call to awaken the voices of Black girls to speak casts light on their experiences and challenges as STEM learners ⎯ from their perspectives. The findings confirm that when credence and counterspaces are given to Black girls, they are poised to reveal their luster toward STEM learning. This study provided a space for Black girls to reflect on their STEM learning experiences, formulate new understandings, and make connections between the informal and formal learning environments within the context of their everyday lives, thus offering a more holistic approach to STEM learning that occurs across settings and over a lifetime

Adapting oecd aquatic toxicity tests for use with manufactured nanomaterials: key issues and consensus recommendations

The unique or enhanced properties of manufactured nanomaterials (MNs) suggest that their use in nanoenabled products will continue to increase. This will result in increased potential for human and environmental exposure to MNs during manufacturing, use, and disposal of nanoenabled products. Scientifically based risk assessment for MNs necessitates the development of reproducible, standardized hazard testing methods such as those provided by the Organisation of Economic Cooperation and Development (OECD). Currently, there is no comprehensive guidance on how best to address testing issues specific to MN particulate, fibrous, or colloidal properties. This paper summarizes the findings from an expert workshop convened to develop a guidance document that addresses the difficulties encountered when testing MNs using OECD aquatic and sediment test guidelines. Critical components were identified by workshop participants that require specific guidance for MN testing: preparation of dispersions, dose metrics, the importance and challenges associated with maintaining and monitoring exposure levels, and the need for reliable methods to quantify MNs in complex media. To facilitate a scientific advance in the consistency of nanoecotoxicology test results, we identify and discuss critical considerations where expert consensus recommendations were and were not achieved and provide specific research recommendations to resolve issues for which consensus was not reached. This process will enable the development of prescriptive testing guidance for MNs. Critically, we highlight the need to quantify and properly interpret and express exposure during the bioassays used to determine hazard values

A Systematic Review of Argumentation Related to the Engineering-Designed World

Background Across academic disciplines, researchers have found that argumentation‐based pedagogies increase learners\u27 achievement and engagement. Engineering educational researchers and teachers of engineering may benefit from knowledge regarding how argumentation related to engineering has been practiced and studied. Purpose/Hypothesis Drawing from terms and concepts used in national standards for K‐12 education and accreditation requirements for undergraduate engineering education, this study was designed to identify how arguments and argumentation related to the engineering‐designed world were operationalized in relevant literature. Methodology Specified search terms and inclusion criteria were used to identify 117 empirical studies related to engineering argumentation and educational research. A qualitative content analysis was used to identify trends across these studies. Findings Overall, engineering‐related argumentation was associated with a variety of positive learner outcomes. Across many studies, arguments were operationalized in practice as statements regarding whether an existing technology should be adopted in a given context, usually with a limited number of supports (e.g., costs and ethics) provided for each claim. Relatively few studies mentioned empirical practices, such as tests. Most studies did not name the race/ethnicity of participants nor report engineering‐specific outcomes. Conclusions Engineering educators in K‐12 and undergraduate settings can create learning environments in which learners use a range of epistemic practices, including empirical practices, to support a range of claims. Researchers can study engineering‐specific outcomes while specifying relevant demographics of their research participants

Epidemiologic approaches to assessing human cancer risk from consuming aquatic food resources from chemically contaminated water.

Epidemiologic approaches to assessing human cancer risk from consuming fish from contaminated waters must confront the problems of long latency and rarity of the end point (cancer). The latency problem makes determination of diet history more difficult, while the low frequency of cancer as an end point reduces the statistical power of the study. These factors are discussed in relation to the study designs most commonly employed in epidemiology. It is suggested that the use of biomarkers for persistent chemicals may be useful to mitigate the difficulty of determining exposure, while the use of more prevalent and timely end points, such as carcinogen-DNA adducts or oncogene proteins, may make the latency and rarity problems more tractable

Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits.

Interest in the use of engineered nanomaterials (ENMs) as either nanomedicines or dental materials/devices in clinical dentistry is growing. This review aims to detail the ultrafine structure, chemical composition, and reactivity of dental tissues in the context of interactions with ENMs, including the saliva, pellicle layer, and oral biofilm; then describes the applications of ENMs in dentistry in context with beneficial clinical outcomes versus potential risks. The flow rate and quality of saliva are likely to influence the behavior of ENMs in the oral cavity, but how the protein corona formed on the ENMs will alter bioavailability, or interact with the structure and proteins of the pellicle layer, as well as microbes in the biofilm, remains unclear. The tooth enamel is a dense crystalline structure that is likely to act as a barrier to ENM penetration, but underlying dentinal tubules are not. Consequently, ENMs may be used to strengthen dentine or regenerate pulp tissue. ENMs have dental applications as antibacterials for infection control, as nanofillers to improve the mechanical and bioactive properties of restoration materials, and as novel coatings on dental implants. Dentifrices and some related personal care products are already available for oral health applications. Overall, the clinical benefits generally outweigh the hazards of using ENMs in the oral cavity, and the latter should not prevent the responsible innovation of nanotechnology in dentistry. However, the clinical safety regulations for dental materials have not been specifically updated for ENMs, and some guidance on occupational health for practitioners is also needed. Knowledge gaps for future research include the formation of protein corona in the oral cavity, ENM diffusion through clinically relevant biofilms, and mechanistic investigations on how ENMs strengthen the tooth structure

Challenging the Science Curriculum Paradigm: TeachingPrimary Children Atomic-Molecular Theory

Solutions to global issues demand the involvement of scientists, yet concern exists about retention rates in science as students pass through school into University. Young children are curious about science, yet are considered incapable of grappling with abstract and microscopic concepts such as atoms, sub-atomic particles, molecules and DNA. School curricula for primary (elementary) aged children reflect this by their limitation to examining only what phenomena are without providing any explanatory frameworks for how or why they occur. This research challenges the assumption that atomic-molecular theory is too difficult for young children, examining new ways of introducing atomic theory to 9 year olds and seeks to verify their efficacy in producing genuine learning in the participants. Early results in three cases in different schools indicate these novel methods fostered further interest in science, allowed diverse children to engage and learn aspects of atomic theory, and satisfied the children’s desire for intellectual challenge. Learning exceeded expectations as demonstrated in the post-interview findings. Learning was also remarkably robust, as demonstrated in two schools eight weeks after the intervention, and in one school, one year after their first exposure to ideas about atoms, elements and molecules