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Molecular assemblies of twisted π molecules of tetraphenylene with long alkoxy chains (1) and tetra[2,3]thienylene with long alkylamide chains (2) or long alkoxy chains (3) and their dielectric properties were investigated. Different degrees of intermolecular interaction of 1–3 afforded different molecular assemblies, including an ordered columnar structure, disordered columnar, and lamellar structures. The introduction of long alkyl chains enabled us to create thermally stable liquid crystalline or liquid states. Temperature-dependent dielectric measurement revealed that the dynamic flipping motion of the tetra[2,3]thienylene core of 3 induced a temperature- and frequency-dependent dielectric anomaly in the neat liquid phase. This flipping motion of the central tetra[2,3]thienylene π core occurred relatively easily in the liquid state with a high degree of freedom of molecular motion.

There is a limited number of reports on mechanically responsive molecular crystals, including thermo-responsive and light-responsive crystals. Rigid ordered molecular crystals with a close-packing structure are less able to accept distortion, which hampers the development of such molecular crystals. The thermosalient effect, or "crystal jumping", refers to a thermo-responsive system that converts heat into mechanical force by thermally induced phase transition. While they have recently attracted attention as potential highly efficient molecular actuators, less than two dozens of thermosalient molecular crystals have been reported to date, and the design of such molecules as well as how they assemble to express a thermosalient effect are unknown. Herein, we demonstrate how the cooperative molecular motion of twisted π units could serve to develop a thermo-responsive jumping molecular crystal with a hydrogen-bonded organic framework (HOF) of tetra[2,3]thienylene tetracarboxylic acid (1). The cooperative change in the molecular structure triggered by the desolvation of THF in the channel of the HOF structure induced not only a change in the structure of HOF but also mechanical force. Hydrogen bonding interactions contributed significant thermal stability to maintain the HOF assembly even with a dynamic structural change.

We demonstrated versatile hydrogen-bonded assemblies of a twisted π system with newly synthesized tetra[3,4]thienylene tetracarboxylic acid ThTCA. Due to its twisted saddle-shaped central π aromatic unit with an anisotropic arrangement of carboxyl units, a variety of dimensional solvate molecular crystals could be obtained, in contrast to typical aromatic carboxylic acid derivatives with low-dimensional assemblies. The versatile molecular assemblies could be converged to ThTCAdesol by desolvation with a simple annealing technique. ThTCAdesol showed selective solvent sorption behavior, which was governed by the solvent association energy and saturated vapor pressure. Especially, ThTCAdesol showed the selective sorption of EtOH, among primary alcohols.

Line-of-sight (LOS) information acquired from the eye is quite valuable in information communication technology (ICT). LOS detection systems that do not impose physical or psychological stress are strongly demanded. In this study, we fabricated and demonstrated a wearable LOS detection system that consists of micro-fabricated transparent optical sensors affixed on eyeglasses. The sensor array detects the difference in the intensity of light reflected from the pupil and the white of the eye (sclera) and then determines the view angle. The system is also equipped with a CCD camera to acquire the user's field-of-view (FOV) to deduce the LOS by using the detected view angle. This paper first presents the shapes and arrangement of the array of four cells on the eyeglasses. With only four sensor cells, we can detect the view angle in both the horizontal and vertical directions. We describe the LOS detection system and show experimentally that the error is as small as 1.5°. In addition, we deduce the characteristic output signals of the cells when the user blinks. Eye-blinking can be used as a trigger to initiate LOS measurement, select objects, etc. Finally, we successfully demonstrate the effectiveness of the proposed system to detect a user's LOS in applications that include the selection of objects to express the user's intent and tracking the point of regards to deduce the user's interest.

The line-of-sight (LOS) detection system has various applications, such as in the field of communication technology, human-computer interaction, safety and security [1]. In early studies, using an external camera and infrared camera to detect the location and motion of the pupil is the mainstream method of detecting LOS. However, these methods involve several problems in that they restrict users' activities and expose them to physical and mental stress. With this in mind, a solution to enhance the practicality of the promising LOS detection applications, with systems that do not impose any restriction on users' activities nor expose them to any stress, is strongly demanded.

The line-of-sight (LOS) detection system has various applications, such as in the field of health and welfare, human-computer interaction, and safety and security. In this paper, we demonstrate a LOS detection system which has micro-fabricated transparent optical sensors on eyeglasses and its applications for information communication technologies (ICT). We first developed the shapes and arrangement of the optical sensor cells that allows us to detect the view angle in both horizontal and vertical directions with only four cells. We achieved the detection accuracy of 1.5 ° in the view angle. Then, we demonstrated applications using the user's LOS detected by the developed system.

A morbidly obese 44-year-old man, weighing 100 kg and 172 cm tall, was admitted to our hospital with severe burn. Forty-seven % of the total body surface area and respiratory tract were injured. Burn index was estimated to be 37. In the emergency room, his trachea was urgently intubated without muscle relaxant and sedatives to manage difficult airway from morbid obesity and airway burn. Pressure support ventilation was started using a ventilator, SAVINA (Dräger, Germany). Simultaneously, sivelestat sodium hydrate was administered for acute lung injury (ALI). On day 3, early skin grafting under general anesthesia was scheduled. The ICU ventilator, SAVINA, was used continuously during anesthesia because his respiratory management had been successful with SAVINA. Total intravenous anesthesia (TIVA) was performed using propofol, fentanyl and vecuronium. To avoid high airway pressure and improve arterial oxygenation, he was positioned at reverse-Trendelenburg's position during anesthesia. Anesthesia and the post-operative course was uneventful.

Our group has developed a wearable eye-tracking system that comprises transparent optical sensors on eyeglasses to detect the reflection from the eye and thus, the position of the eye, where photovoltaic cells are used as the sensors. In this paper, crosstalk, or electric interference, among the photovoltaic cells is discussed. The crosstalk makes the neighboring sensors dependent on each other, which leads to large errors in eye-tracking. We experimentally investigated the source of crosstalk by testing different designs of photovoltaic cells and their interconnection. It was revealed that sharing of the electrolyte by the photovoltaic devices was dominant. In addition, overlapping circuits were found to contribute to the crosstalk. We revised the design of the sensors and successfully reduced the crosstalk and improved the accuracy.