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Relative humidity sensors are used for high-humidity measurement and moisture sensor or dew point sensors are used for low-humidity measurement (<1 ppmv). We fabricated moisture sensors using α-Al2O3films as porous dielectric materials deposited by anodic spark deposition. In this study, a variety number of small pores has been studied to investigate the response speed of moisture sensors. Three different surface morphologies have been studied using scanning electron microscopy. One sample has the maximum number of small pores, one sample has the medium number of small pores, and the last sample has the minimum number of small pores. Small pores are defined as pore size ranging from 40 nm to 200 nm. We found that the sensor made as porous material with the maximum number of small pores has the fastest response speed, and that from the minimum number of small pores has the slowest response speed either from high humidity to low humidity or from low humidity to high humidity.

Four genes encode electroneutral, Na+‐independent, K–Cl cotransporters. KCC2, is exclusively expressed in neurons where it is thought to drive intracellular Cl−to low concentrations and shift the reversal potential for Cl−conductances such as GABAAor glycine receptor channels, thus participating in the postnatal development of inhibitory mechanisms in the brain. Indeed, expression of the cotransporter is low at birth and increases postnatally, at a time when the intracellular Cl−concentration in neurons decreases and γ‐aminobutyric acid switches its effect from excitatory to inhibitory. To assert the significance of KCC2 in neuronal function, we disrupted the mouse gene encoding this neuronal‐specific K–Cl cotransporter. We demonstrate that animals deficient in KCC2 exhibit frequent generalized seizures and die shortly after birth. We also show upregulation of Fos, the product of the immediate early gene c‐fos, and the significant loss of parvalbumin‐positive interneurons, both indicative of brain injury. The regions most affected are the hippocampus and temporal and entorhinal cortices. Extracellular field potential measurements in the CA1 hippocampus exhibited hyperexcitability. Application of picrotoxin, a blocker of the GABAAreceptor, further increased hyperexcitability in homozygous hippocampal sections. Pharmacological treatment of pups showed that diazepam relieved the seizures while phenytoin prevented them between postnatal ages P4–P12. Finally, we demonstrate that adult heterozygote animals show increased susceptibility for epileptic seizure and increased resistance to the anticonvulsant effect of propofol. Taken together, these results indicate that KCC2 plays an important role in controlling CNS excitability during both postnatal development and adult life. Hippocampus 2002;12:258–268. © 2002 Wiley‐Liss, Inc.

A criticism of current methods reveals the problems of planning a large building complex. The results of recent research on health sciences centres suggest that there may be a more profitable approach.