Abstract:To reduce consumption for ambient assisted living (AAL) applications, we propose the design and fabrication of flexible thin-film thermoelectric generators at a low manufacturing cost. The generators were fabricated using a combination of electrodeposition and transfer processes. N-type Bi 2 Te 3 films and p-type Sb 2 Te 3 films were formed on a stainless-steel substrate employing potentiostatic electrodeposition using a nitric acid-based bath, followed by a transfer process. Three types of flexible thin-film thermoelectric generators were fabricated. The open circuit voltage (V oc ) and maximum output power (P max ) were measured by applying a temperature difference between the ends of the generator. The thin-film generators obtained using thermoplastic sheets with epoxy resin exhibited a V oc that was tens of millivolts. In particular, the contact resistance of the thin-film generator decreased when silver paste was inserted at the junctions between the n-and p-type films. The most flexible thin-film generator fabricated in this study exhibited a P max of 10.4 nW at a temperature difference of 60 K. The current performance of the generators was too low, but we innovated a combination process to prepare them. It is expected to increase the performance by further decreasing the micro-cracks and contact resistance in the generators.

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Abstract:In order to standardize test procedures for evaluation of neurotoxicity of chemical exposure, a collaborative study with a common protocol based on the Organization for Economic Cooperation and Development (OECD) test guideline TG407 was conducted by eleven laboratories, using acrylamide and 3,3'-iminodipropionitrile (IDPN) as positive neurotoxicants. This report summarizes the results of this neuropathological evaluation of neurotoxicity, when acrylamide (3, 10, and 30 mg/kg) and IDPN (20, 50, and 100 mg/kg) were orally administered to rats for 28 days. The study revealed typical alterations, including degeneration of peripheral nerve fibers and Purkinje's cell necrosis with acrylamide, and axonal swelling in the brainstem and spinal cord with IDPN. In addition to the neurotoxicity, IDPN exerted toxic effects on the cerebral arteries, hyalinization of vessel walls being observed. In general, the neuropathological findings well demonstrated the neurotoxicity of both chemicals. These results indicate that neuropathological evaluation can play a crucial role in screening for potential neurotoxicants with risk for human health, the expected neurotoxic effects being detected in this collaborative study consistently in all the laboratories. (J Toxicol Pathol 2001; 14: 279-287)

Cationic amphiphilic drugs (CADs) can induce phospholipidosis (PLD) in organs/tissues. Several ophthalmic pharmaceuticals containing CADs are marketed and used in children. To investigate the effect of PLD on the developing cornea, chloroquine and amiodarone, which are representative CADs, were applied topically to the eyes of juvenile rabbits, and the effects in juvenile rabbits were compared with those in young adult rabbits. Diffuse corneal cloudiness was observed in chloroquine-and amiodarone-treated eyes. Histopathologically, vacuolation was observed in the corneal epithelium and keratocytes. On ultrastructural examination, these vacuoles contained multilamellar inclusion bodies, which are a characteristic of PLD. The size of the vacuoles in the corneal epithelium was reduced in juveniles compared with young adults. Cytoplasmic lamellar bodies and exocytosis in the corneal endothelium were observed in young adult rabbits but not in juvenile rabbits. This study revealed that topical application of chloroquine or amiodarone induces corneal PLD in juvenile and young adult rabbits. Corneal endothelial changes occurred only in young adult rabbits, but ophthalmological changes were similar between juveniles and young adults. The results of the study suggest that the effects of corneal PLD were similar among age groups based on risk assessment.

Vacuolar degeneration of the thyroid follicular epithelium was observed in two untreated female cynomolgus monkeys assigned to control groups. In light microscopy, large vacuoles containing a homogenous substance occupied the basal region of the epithelium, and the nuclei had shifted toward the apical region. The vacuoles showed negative reactions to PAS and thyroglobulin. Electron microscopic observation revealed dilatation of the rough endoplasmic reticulum corresponding to the vacuoles. The plasma TSH, T3 and T4 levels determined for the samples kept frozen were within the normal ranges, suggesting that the thyroid function was kept intact.