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Notes: The fabrication process on a graphite surface is investigated using scanning tunneling microscopy, with emphasis on the effects of high electric field associated with voltage pulse. We have demonstrated that two distinct types of features can be repeatedly produced and are found to be correlated with tip–sample separation, displaying a threshold behavior. By correlating the observation with the general trend of tunneling barrier height versus tip–sample separation, it is suggested that field emission and electrical breakdown are the driving mechanisms for generating craters and mounds, respectively. © 1997 American Institute of Physics.

Notes: Al films deposited on sputtered-TiN/Si substrate by metalorganic chemical vapor deposition (MOCVD) from dimethylethylamine alane (DMEAA) were characterized using x-ray diffraction (XRD), Auger electron spectroscopy (AES), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The TiN film sputtered on the Si has a preferred orientation along the growth direction with the 〈111〉 of the film parallel to the Si〈111〉. Sputtering of the TiN film on the Si induced strains at the interface. The TiN/Si interface is flat while the Al/TiN interface is rough. There exist many dislocations at the Al/TiN interface. The Al2O3 phase was formed at the Al/TiN interface during the early stages of Al deposition. In the Al grains, there exist many tangled dislocations and a few Al2O3 particles. With increasing deposition time, the Al film surface roughness increases. © 1995 American Institute of Physics.

Notes: The characteristics of the nanostructure on the surface of highly oriented pyrolytic graphite (HOPG) involving field emitted electrons is examined with scanning tunneling microscopy (STM). A simple model based on the continuum electron diffusion is proposed and is compared with the experimental results. It suggests that the process could be associated with the diffusion of electrons at the vicinity of the injection position. It also implies that the characteristics of the as-produced nanometer sized craters could be correlated to the anisotropy degree of the transport properties of HOPG. © 1996 American Institute of Physics.

Notes: Deposition of aluminum film from DMEAA in the temperature range of 100–300 °C has been studied. In this temperature range, there is a maximum deposition rate at around 150 °C. The film deposited at 190 °C has elongated blocklike grain shapes, which are ∼600 nm in width and 930 nm in length. Grains in the film deposited at 150 °C showed an equiaxed structure with grain size in the range of 100–300 nm in a film with 600 nm thickness. Aluminum oxide particle inclusion was observed especially at high deposition temperature. Plausible reaction pathways of DMEAA dissociation were suggested to explain the experimental observations. © 1996 American Institute of Physics.

Notes: Abstract The pineal gland expresses a group of proteins essential for rhythmic melatonin production. This pineal-specific phenotype is the consequence of a temporally and spacially controlled program of gene expression. Understanding of pineal circadian biology has been greatly facilitated in recent years by a number of molecular studies, including the cloning of N-acetyltransferase, the determination of the in vivo involvement of the cAMP-inducible early repressor in the regulation of N-acetyltransferase, and the identification of a pineal transcriptional regulatory element and its interaction with the cone-rod homeobox protein. Likewise, appreciation the physiological roles of melatonin has increased dramatically with the cloning and targeted knockout of melatonin receptors. With these molecular tools in hand, we can now address more specific questions about how and why melatonin is made in the pineal at night and about how it influences the rest of the body.

Notes: Libraries have been integrating active server pages (ASP) with Web-based databases for searching and retrieving electronic information for the past five years; however, a literature review reveals that a more complete description of modifying data through the Web interface is needed. At the Texas A&M University Libraries, a Web database of Internet links was developed using ASP, Microsoft Access, and Microsoft Internet Information Server (IIS) to facilitate use of online resources. The implementation of the Internet Links database is described with focus on its data management functions. Also described are other library applications of ASP technology. The project explores a more complete approach to library Web database applications than was found in the current literature and should serve to facilitate reference service.

Notes: A 2-year-old boy with flat and spoon-shaped nail plates was referred to us. His mother had noticed that his fingernails were quite soft when he was born. After 2 months, the nails became flat or spoon-shaped; the toenail plates also became rough and flat. Systemic examination revealed nothing unusual. All his fingernail plates were quite thin, and had concave surfaces; the distal edges of some nail plates were rough and darkened (〈link href="#f4-1"〉Fig. 1). His great, second and middle toenails on both sides showed the same abnormalities as the fingernails. Routine laboratory tests were normal; serum levels of iron, zinc, calcium, and magnesium were within normal limits. Repeated microscopic examination and culture of fungi from both fingernails and toenails were negative. Histologic examination of the distal edges of some of his fingernail plates was basically normal.〈figure xml:id="f4-1"〉1〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1212-5:IJD_1212_f4-1"/〉The proband has concave fingernail plates with rough and light brown distal edgesWhen checking members of the family, we noticed that the boy's mother and maternal grandmother had similar nail problems (out of 14 members of three generations), although no systemic or other skin disorders were noticed. All the fingernails of the boy's mother were lusterless and concave with darkening of the distal edges (〈link href="#f4-2"〉Fig. 2). All her toenails were rough, lusterless, and brown; some of them had longitudinal ridges. His maternal grandmother had light brown colored fingernail plates with concave profiles (〈link href="#f4-3"〉Fig. 3), and dark brown or even blackish colored toenails. Both the mother and maternal grandmother acknowledged that their nails were abnormal from early childhood. Repeated microscopic examination and culture of fungi from both fingernails and toenails were negative. Several distal portions of the nail plates were collected for histologic examination. The fingernail plates of the boy's mother showed numerous parakeratotic cells in the middle zone, and those of his maternal grandmother showed diffuse parakeratotic cells; melanin granules were not found in those nail plates that were checked. Taken together, a diagnosis of familial koilonychia was established.〈figure xml:id="f4-2"〉2〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1212-5:IJD_1212_f4-2"/〉The boy's mother has concave fingernail plates with brown colored distal halves〈figure xml:id="f4-3"〉3〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1212-5:IJD_1212_f4-2"/〉The boy's maternal grandmother has concave fingernail plates with a dark brown color