Intellectual and motor development of children at 25-30 months of age is separately associated with abnormalities of maternal thyroid at 16-20 weeks gestation. Maternal subclinical hypothyroidism, hypothyroxinaemia or euthyroidism with elevated TPOAb titres were all statistically significant predictors of lower motor and intellectual development at 25-30 months.

Herein, we report electrodeposited nickel-based thin film (NiOx) on multiwalled carbon nanotubes (MWCNTs) as a highly efficient bifunctional catalyst for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Under reductive conditions (-1.2 V vs Ag/AgCl), the hydrogen evolution catalyst (H2-NiO(x)) was facilely deposited on MWCNTs. The resulting film demonstrates good catalytic activity for hydrogen production in a near-neutral aqueous solution at low overpotential. When switched to oxidative conditions (+1.1 V vs Ag/AgCl), the amorphous H2-NiO(x) film onto MWCNTs can be transformed into another amorphous material (O2-NiO(x)) to efficiently catalyze OER. The NiO(x)-MWCNTs catalyst was further characterized by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). The results show that the content of oxygen in the O2-NiO(x)-MWCNTs film is higher than that in the H2-NiO(x)-MWCNTs film. The NiOx-MWCNTs catalyst has good catalytic stability, and the film is reversible when the potentials are switched between the reductive conditions and oxidative conditions. The Faradaic efficiencies of hydrogen and oxygen production are >95%.

A microfluidic device was designed and fabricated for non-photochemical laser-induced nucleation (NPLIN) in continuous laminar flow, which enabled real-time in situ characterization of crystal size, shape, growth, and polydispersity. On-chip thermoelectric cooling created supersaturation by lowering the solution temperature. The influences of laser power density, laser exposure time, flow rate, and supersaturation were examined for aqueous KCl solutions. The observed threshold peak power densities and solution labilities agreed with those reported by Alexander et al. using static cells. The mean crystal size just downstream from the irradiated region was observed to increase with increasing supersaturation. The number of crystals nucleated was found to increase with increasing supersaturation and laser power density but was independent of the number of laser pulses to which the solution was exposed. These results are consistent with the dielectric polarization model of Alexander et al. Our findings broaden the scope of nucleation in a light field by introducing a way to directly characterize the crystallization.

Nonphotochemical laser-induced nucleation (NPLIN) of supersaturated aqueous glycine solutions was studied at a wavelength of 1064 nm using a microfluidic device. Crystal shape, size, and number were characterized in situ in real time on the chip. The influence of the laser pulse intensity on the nucleation kinetics was reported. Aging of the supersaturated solutions was necessary to observe NPLIN; fresh solutions did not nucleate. Crystal structure was found to switch from the αto the γ-polymorph as the supersaturation increased. The observed number of crystals formed exhibited a threshold intensity but was otherwise proportional to the laser intensity, consistent with the dielectric polarization model, although the "lability" calculated from classical nucleation theory was too large by many orders of magnitude. Dynamic light scattering data revealed nanodroplets, hundreds of nanometers in diameter, formed in aged supersaturated aqueous glycine solutions; these submicron sized nanodroplets were apparently necessary for NPLIN. A new model combining the dielectric polarization model and two-step nucleation theory via submicron nanodroplets was proposed to explain these observations, providing a reasonable match between experiment and theory.

Tightly focusing a continuous-wave, near-infrared laser beam at the air/solution interface of a millimeter-thick layer of glycine in D2O forms a crystal through a polymorphically and spatially controlled nucleation process known as gradient-force laser-induced nucleation or optical-tweezer laser-induced nucleation. However, when this same beam is focused at the glass/solution interface of a film of aqueous glycine, a highly concentrated laser-induced phase-separated (LIPS) solution droplet is formed that does not nucleate while the focusing beam remains on. Two competing theories have emerged about the nature of the LIPS droplet: one proposes that it is a merger of prenucleation metastable nanodroplets and clusters into one large homogeneous “dense liquid droplet”, and the other stipulates that it is the result of the partitioning of larger droplets into the new phase, but not a merging of droplets, around the focal point of the beam. In order to determine the nature of the LIPS droplet, dynamic light scattering was used to detect the presence of nanodroplets undergoing Brownian motion within the droplet and to measure their relative size following a range of laser exposure times. The observation of nanodroplets in motion in the center of the LIPS droplet revealed that the application of optical tweezers at the glass/solution interface forms a relatively monodisperse collection of large nanodroplets (>700 nm) concentrated around the focal point of the beam with smaller particles (<100 nm) depleted within the first 2 min of laser exposure. The LIPS droplet quickly reaches a steady state and is not affected by increasing focusing times. These findings allow for a better understanding of the interactions of optical tweezers with aqueous glycine nanodroplets. This understanding will help in studying the fundamental nature of metastable nanodroplets. More practically, laser-induced phase separation makes possible the nucleation-free separation of large nanodroplets from small clusters, facilitating materials technologies such as high purity, polymorphically selective nucleation of crystals and co-crystals used for pharmaceuticals, dyes, and photovoltaics.