A thermoresponsive smart window that can switch its transmittance to control heating from sunlight is attracting great attention. Such windows made from a hydrogel of a thermoresponsive polymer such as poly­(N-isopropylacrylamide) (PNIPAm) or hydroxypropyl cellulose (HPC) have been successful and can switch their transmittance at room temperature. However, such hydrogels occasionally freeze in cold places, degrading their transmittance. Thus, a thermoresponsive hydrogel that can be used in various geographical regions is desired. Here, we produced a thermoresponsive smart window with freezing resistance made from HPC and glycerol. We could adjust its switching temperature by simply changing the amount of added glycerol, letting us easily change it to room temperature for practical use. These smart windows show high cyclic performance, freezing resistance, and heat shielding, demonstrating great potential.

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Little is known about the differences in the distributions of inhibitory and excitatory synapses in the dendritic tree of single motoneurons in the brainstem and spinal cord. In this study, the distribution of γ‐aminobutyric acid (GABA)‐, glycine‐, and glutamate‐like immunoreactivity in axon terminals on dendrites of cat masseter α‐motoneurons, stained intracellularly with horseradish peroxidase, was examined by using postembedding immunogold histochemistry in serial ultrathin sections. The dendritic tree was divided into three segments: primary (Pd) and distal (Dd) dendrites and intermediate (Id) dendrites between the two segments. Quantitative analysis of 175, 279, and 105 boutons synapsing on 13 Pd, 54 Id, and 81 Dd, respectively, was performed. Fifty percent of the total number of studied boutons were immunopositive for GABA and/or glycine and 48% for glutamate. Among the former, 27% showed glycine immunoreactivity only and 14% were immunoreactive to both glycine and GABA. The remainder (9%) showed immunoreactivity for GABA only. As few as 3% of the boutons were immunonegative for the three amino acids. Most boutons immunoreactive to inhibitory amino acid(s) contained a mixture of spherical, oval, and flattened synaptic vesicles. Most boutons immunoreactive to excitatory amino acid contained clear, spherical, synaptic vesicles with a few dense‐cored vesicles. When comparisons of the inhibitory and excitatory boutons were made between the three dendritic segments, the proportion of the inhibitory to the excitatory boutons was high in the Pd (60% vs. 37%) but somewhat low in the Id (46% vs. 52%) and Dd (44% vs. 53%). The percentage of synaptic covering and packing density of the inhibitory synaptic boutons decreased in the order Pd, Id, and Dd, but this trend was not applicable to the excitatory boutons. The present study provides possible evidence that the spatial distribution patterns of inhibitory and excitatory synapses are different in the dendritic tree of jaw‐closing α‐motoneurons. J. Comp. Neurol. 414:454–468, 1999. © 1999 Wiley‐Liss, Inc.

As frost formation and ice accumulation result in serious problems in various industrial systems, some anti-icing system is highly required, and passive anti-icing processes based on ice prevention coatings have attracted much attention. Recently, antifreeze liquid-infused surfaces (LISs) have been developed for the preparation of ice-phobic surfaces owing to their low ice adhesion strength and antifrosting properties. However, it is still challenging to add an optical function such as high transparency to antifreeze LISs despite the potential for the application in window coatings. In addition, the influence on anti-icing properties by the thickness of antifreeze liquid layer and base layer are still unclear. Here, we designed highly transparent coating surfaces that were resistant to ice adhesion and frost formation. We controlled the thickness, surface roughness, and refractive index of the base layer through a spray layer-by-layer (LbL) method and then investigated the effect on the optical properties, ice adhesion strength, and frost formation behavior. The frost-resisting properties of the surfaces were clearly improved with the increase of the lubricant thickness as well as the increase of the number of bilayers; the parallel transmittance of antifreeze LIS composed of ethylene glycol and this base layer was approximately 92.6%, and the ice adhesion strength was below 17 kPa regardless of the number of bilayers. These results indicated that a high lubricant thickness coating can achieve both excellent anti-icing properties and transparency; the antifreeze LIS based on a 100 bilayer base coating had excellent antifrosting properties owing to its thick antifreeze liquid layer and maintained both of high transparency and low ice adhesion. Furthermore, the spray LbL method makes it possible to fabricate the base layer in short time and also in large scale, which is quite useful for the practical application of antifreeze LIS. This work will be of enormous help for the design of transparent anti-icing coatings as well as industrial applications such as solar cells and the windows of transportation vehicles.

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