Solution-based Supramolecular Hierarchical Assembly of Frenkel Excitonic Nanotubes Driven by Gold Nanoparticle Formation and Temperature.

Translating nature's successful design principle of solution-based supramolecular self-assembling to broad applications─ranging from renewable energy and information technology to nanomedicine─requires a fundamental understanding of supramolecular hierarchical assembly. Though the forces behind self-assembly (e.g., hydrophobicity) are known, the specific mechanism by which monomers form the hierarchical assembly still remains an open question. A crucial step toward formulating a complete mechanism is understanding not only how the monomer's specific molecular structure but also how manifold environmental conditions impact the self-assembling process. Here, we elucidate the complex correlation between the environmental self-assembling conditions and the resulting structural properties by utilizing a well-characterized model system: well-defined supramolecular Frenkel excitonic nanotubes (NTs), self-assembled from cyanine dye molecules in aqueous solution, which further self-assemble into bundled nanotubes (b-NTs). The NTs and b-NTs inhabit distinct spectroscopic signatures, which allows the use of steady-state absorption spectroscopy to monitor the transition from NTs to b-NTs directly. Specifically, we investigate the impact of temperature (ranging from 23 °C, 55 °C, 70 °C, 85 °C, up to 100 °C) during in situ formation of gold nanoparticles to determine their role in the formation of b-NTs. The considered time regime for the self-assembling process ranges from 1 min to 8 days. With our work, we contribute to a basic understanding of how environmental conditions impact solution-based hierarchical supramolecular self-assembly in both the thermodynamic and the kinetic regime.

The importance of training transfer of non-technical skills safety training of construction workers.

Safety training of migrant workers in construction has focused on technical skills with limited attention to non-technical skills, which support safety training transfer to the worksite, both immediately after training and in the long term. Using realist evaluation as our theoretical framework, this study explores the transfer of two key non-technical skills to construction sites: communication and decision-making. Trained workers completed questionnaires post-training and after six months. A moderated mediation model found an indirect link through training transfer between communication and decision-making skills immediately post-training and six months later. The results also revealed that high levels of safety self-efficacy moderated the relationship between communication, but not decision-making, safety skills post-training and the extent to which trained workers reported transferring these skills. The study has important practical implications, showing the significance of training transfer of non-technical skills, such as communication and decision-making, to the worksite.

Does bystander behavior make a difference? How passive and active bystanders in the group moderate the effects of bullying exposure.

Workplace bullying has negative effects on targets' well-being. Researchers are increasingly aware that bullying occurs within social contexts and is often witnessed by others in the organization, such as bystanders. However, we know little about how bystanders' responses influence outcomes for those exposed to bullying. In this multilevel study, involving 572 employees within 55 work groups, we explore how bystanders' passive (e.g., inaction) and active constructive (e.g., defending the target) responses to bullying can affect targets' somatic symptoms and work engagement. Drawing from Job-Demands Resource theory, we propose that passive and active constructive bystanders can worsen or buffer bullying's effects on these well-being outcomes, respectively. Specifically, we propose that passive bystanders can act as further demands for targets to cope with, leading to demand accumulation, while active constructive bystanders can act as resources. We found that exposure to workplace bullying was associated with somatic symptoms and low work engagement. The number of passive and active constructive bystanders in the target's work group moderated the relationship between exposure to bullying and engagement. In particular, with larger numbers of passive bystanders, the negative relationship of bullying exposure with engagement strengthened. Conversely, with a higher number of active constructive bystanders, bullying's negative relationship with engagement was mitigated. However, there was no moderating effect for somatic symptoms. This study contributes as the first empirical test of whether bystander behavior shapes the consequences of bullying for targets and provides a novel, group-level perspective to the bullying bystander literature. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Frenkel excitons in heat-stressed supramolecular nanocomposites enabled by tunable cage-like scaffolding.

Delocalized Frenkel excitons-coherently shared excitations among chromophores-are responsible for the remarkable efficiency of supramolecular light-harvesting assemblies within photosynthetic organisms. The translation of nature's design principles to applications in optoelectronic devices has been limited by the fragility of the supramolecular structures used and the delicate nature of Frenkel excitons, particularly under mildly changing solvent conditions and elevated temperatures and upon deposition onto solid substrates. Here, we overcome those functionalization barriers through composition of stable supramolecular light-harvesting nanotubes enabled by tunable (~4.3-4.9 nm), uniform (±0.3 nm) cage-like scaffolds. High-resolution cryogenic electron microscopy, combined with scanning electron microscopy, broadband femtosecond transient absorption spectroscopy and near-field scanning optical microscopy revealed that excitons within the cage-like scaffolds are robust, even under extreme heat stress, and control over nanocomposite dimensions is maintained on solid substrates. Our bio-inspired nanocomposites provide a general framework for the development of next-generation organic devices made from stable supramolecular materials.

Malformations among infants of mothers with insulin-dependent diabetes: Is there a recognizable pattern of abnormalities?

BACKGROUND: Infants of diabetic mothers have been shown in several studies to have an increased frequency of malformations. In previous studies, an increased frequency of several specific malformations has been noted, including anencephaly, bilateral renal agenesis, and double outlet right ventricle. Surveillance, used to identify all malformed infants in a consecutive sample of births, can identify a distinctive pattern of malformations among the affected infants. METHODS: The infants of insulin-dependent, pregestational diabetic mothers were identified in the daily review of the medical records of each newborn infant with a malformation and her/his mother's medical record. Infants of mothers with gestational diabetes were excluded. The frequency of each malformation was compared to that among the malformed infants of nondiabetic mothers. RESULTS: One hundred and eighty-three malformed infants of diabetic mothers were identified among the 289,365 births. The most notable malformations were: neural tube defects (anencephaly, 9%), heart defects (transposition of great arteries, 4%), bilateral renal agenesis or dysgenesis (6%), and vertebral anomalies (hemivertebrae, 4%). CONCLUSIONS: There was a recognizable pattern of malformations and characteristics of infants of diabetic mothers, although there was variation in the pattern among affected infants. Some of the malformations in the diabetic embryopathy can be identified in prenatal screening by ultrasound. More important, their occurrence can be reduced significantly by the mother achieving much better control of her diabetes mellitus prior to conception.

An assessment of mercury in estuarine sediment and tissue in Southern New Jersey using public domain data.

Mercury (Hg) is considered a contaminant of global concern for coastal environments due to its toxicity, widespread occurrence in sediment, and bioaccumulation in tissue. Coastal New Jersey, USA, is characterized by shallow bays and wetlands that provide critical habitat for wildlife but share space with expanding urban landscapes. This study was designed as an assessment of the magnitude and distribution of Hg in coastal New Jersey sediments and critical species using publicly available data to highlight potential data gaps. Mercury concentrations in estuary sediments can exceed 2µg/g and correlate with concentrations of other metals. Based on existing data, the concentrations of Hg in mussels in southern New Jersey are comparable to those observed in other urbanized Atlantic Coast estuaries. Lack of methylmercury data for sediments, other media, and tissues are data gaps needing to be filled for a clearer understanding of the impacts of Hg inputs to the ecosystem.