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In a previous study, which used a cross-cultural method, apparently stressful infant-care practices, including immunological inoculations, were found to be associated with greater adult stature. In the present study, data from 2 longitudinal-growth studies were analyzed. With parental stature held constant statistically, the adult stature of individuals inoculated before 2 years of age was significantly greater than that of individuals not so inoculated. This and a variety of other sources of evidence bearing on the possible growth-accelerating influence of early physiological stress were compared and the present status of the question evaluated. [ABSTRACT FROM AUTHOR]

Developing coordination complexes of earth abundant metals that can perform substrate oxidations under benign conditions is an ongoing challenge. Herein, the reactivity of two mononuclear Cu-complexes toward the oxidant H 2 O 2 is reported. Both complexes displayed ligand oxidation upon reaction with the oxidant. Analysis of spectroscopic data established that the respective product complexes contained mononuclear Cu(II) centers. Moreover, treatment of these Cu-complexes with oxidant in the presence of substrate resulted in the interception of ligand oxidation with preferential oxidation of the substrate. Computational studies identified plausible mechanistic pathways, suggesting a copper-oxyl intermediate as the likely reactive intermediate responsible for substrate and ligand oxidation. To our knowledge, this is the first Cu-mediated system that showed ligand oxidation, oxo-transfer capability, and external hydrocarbon oxidation under stoichiometric conditions. Mononuclear Cu-mediated hydrocarbon oxidation: reactivity of mononuclear copper system toward hydrogen peroxide/triethylamine and its ability to oxidize external substrates has been demonstrated. This is the first report of a system where ligand oxidation, oxo-transfer reaction and hydrocarbon oxidation was observed. Unlabelled Image • Reactivity of mononuclear Cu complexes with hydrogen peroxide/triethylamine is reported. • The presence of mononuclear Cu(II) centers was established spectroscopically. • Computational studies identified plausible mechanistic pathways. • Ligand oxidation, oxo transfer reaction and hydrocarbon oxidation were observed. [ABSTRACT FROM AUTHOR]

Abstract Here we present a new 4D printing technique capable of producing a diverse range of trilayer constructs using commercial low-cost desktop 3D printers. This unique methodology permits the viable construction of dynamically robust and complex origami architectures for a new generation of active structures. The resulting creations transform from flat 2D parts to 3D structures through submersion in water and return to their original configuration through dehydration. This technique uses commercially available materials and printers to enable a 4D printing method that is more accessible and affordable than previous examples of hydration triggered 4D printing. This method yields a controlled and predictable actuation route and final shape, enabling it to be used for both simple and complex origami inspired designs, such as the tessellated waterbomb origami pattern, a design that has not previously been realised with 4D printing. These new designs demonstrate how the integration of multiple trilayers into a single 3D print enables through-thickness control of actuation and resulting formation of active structures with complexity beyond what has previously been achieved with 4D printing. Graphical Abstract Highlights • Thermoplastic polyurethane hydrogel filament was manufactured and 3D-printed into multi-material structures. • A range of trilayer constructs with hydration-triggered hydrogel hinges were produced using low-cost desktop 3D printers. • The effect of varying hinge geometry on the final actuation angle and the transient actuation progression was investigated. • Complex tessellated origami structures were produced which had not been previously realised by 4D-printing. [ABSTRACT FROM AUTHOR]

Pediatric cervical spine injuries are rare and are associated with significant morbidity and mortality. Pediatric anatomy and physiology predispose to upper cervical spine injury and spinal cord injury without radiologic abnormality in contrast to lower cervical spine injury seen in adults. Care of pediatric patients is difficult because they have a greater head-to-body ratio than adults and may have difficulty cooperating with a history and physical examination. In evaluating a child with a suspected cervical spine injury, radiography may be supplemented with CT or MRI. Definitive management of pediatric cervical spine trauma must be adapted to the distinctive anatomy and growth potential of the patient. As with all injuries, prevention is necessary to reduce the incidence of trauma to the pediatric spine.