The association between prehospital vital signs of children and their critical clinical outcomes at hospitals.

Vital signs are important for patient assessment, but little is known about interpreting those of children in prehospital settings. We conducted an observational study to investigate the association between prehospital vital signs of children and their clinical outcomes in hospitals. We plotted the data of patients with critical outcomes on published reference ranges, such as those of healthy children to evaluate the clinical relevance. Of the 18,493 children screened, 4477 transported to tertiary hospitals were included in the analysis. The outcomes 12 h after being transported to a tertiary hospital were as follows: deceased, 41; hospitalization with critical deterioration events, 65; hospitalization without critical deterioration events, 1086; returned home, 3090; and unknown, 195. The reference ranges of the heart rates (sensitivity: 57.7%, specificity: 67.5%) and respiratory rates (sensitivity: 54.5%, specificity: 67.7%) of healthy children worked best to detect the critical outcomes. Therefore, the reference ranges of healthy children were concluded to be suitable in prehospital settings; however, excessive reliance on vital signs carried potential risks due to their limited sensitivities and specificities. Future studies are warranted to investigate indicators with higher sensitivities and specificities.

Stereoselectivity in spontaneous assembly of rolled incommensurate carbon bilayers.

The periodicity of two-dimensional entities can be manipulated by their stacking assembly, and incommensurate stacks of bilayers are attracting considerable interest in materials science. Stereoisomerism in incommensurate bilayers was first noted with incommensurate double-wall carbon nanotubes composed of helical carbon networks, but the lack of structural information hampered the chemical understanding such as the stereoselectivity during bilayer formation. In this study, we construct a finite molecular version of incommensurate carbon bilayers by assembling two helical cylindrical molecules in solution. An outer cylindrical molecule is designed to encapsulate a small-bore helical cylindrical molecule, and the spontaneous assembly of coaxial complexes proceeds in a stereoselective manner in solution with a preference for heterohelical combinations over diastereomeric, homohelical combinations. The rational design of incommensurate bilayers for material applications may be facilitated by the design and development of molecular versions with discrete structures with atomic precision.

Ineffective OH Pinning of the Flipping Dynamics of a Spherical Guest within a Tight-Fitting Tube.

A supramolecular/synthetic method has been devised to affix a sterically hindered substituent onto a fullerene guest encapsulated in a tubular host. A two-wheeled complex of (C59 N)-(C59 N) with a tubular host was oxidatively bisected to afford a C59 N+ cation captured in the tube. The C59 N+ cation in the tube was then trapped by ethanol or water, which led to an oxy substituent pinned on the guest. The guest motions within the tube were modulated by the pinned substituent, and up-and-down flipping motions were halted by an ethoxy substituent. A hydroxy substituent, however, was ineffective in halting the flipping motions, despite the tight-fitting relationship between the tubular host and the spherical guest. Theoretical calculations of the dynamics revealed that the flipping motions were assisted by OH-π hydrogen bonds between the guest and the carbon-rich wall and that sliding motions of the OH group were also facilitated by deformations of the tube.

Regulated Single-Axis Rotations of a Carbonaceous Guest in a van†der Waals Complex with an Entropy Cost.

In a tight host-guest complex assembled solely by nondirectional van der Waals forces, unique motions of the guest, such as solid-state inertial rotations, emerge. The regulation of dynamic motions is an important element to be explored for novel functions of such complexes, which may be seemingly difficult to achieve because of the nondirectionality of the assembling forces. A regulated, single-axis rotation was made possible by choosing an appropriate shape of the guest in the tubular host. Specifically, an ellipsoidal guest was made to stand along a cylinder axis of the host, which consequently resulted in single-axis rotations of the guest in the solid. The rotational frequency was considerably high for solid-state rotations but was suppressed to 10 GHz, which was 1/20 of the isotropic rotation of a spherical guest. In-depth kinetic analyses quantitatively revealed that the entropy cost was a determining factor that regulated the dynamics.