Complex frequency technique for linear and second harmonic optical properties of metallic surfaces

We describe a complex frequency technique for evaluating the linear and quadratic dielectric responses of metal surfaces, illustrated by application to the surface of jellium. The electric susceptibilities are shorter-range functions of the spatial coordinates at complex frequency, whereas their general behaviour is complicated, long-range and highly oscillatory at real frequency. As a result the linear and the second harmonic electric charges induced by an optical perturbation are then numerically easier to calculate at complex frequency. As the functions which characterize the optical behaviour of the metal surface are analytic in the upper complex frequency half-plane, the dielectric response at real frequency can be deduced by analytic continuation from the results at complex frequency. We illustrate and discuss this approach, which should be useful for studying more realistic models of a surface in which the crystal potential is included, and where a direct calculation of the dielectric response is difficult to obtain at real frequency.     

Quadratic solitons: recent developments

Multicolor optical solitons mediated by quadratic nonlinearities have been observed experimentally during the last few years in a variety of materials and geometries in a number of laboratories around the world. Today, many of the basic properties of the corresponding soliton families are theoretically well established. Nevertheless, experiments continuously reveal new surprises, and the topic is entering new theoretical and experimental territories. In this paper, we briefly outline the key features of the quadratic solitons and overview the latest developments.     

Relationships between identity formation and computer use among black and white emerging adult females

The purpose of this study was to examine the relationships between computer use, identity formation, and self-esteem among Black and White emerging adult females. One hundred 56 female college students participated in this study by completing a survey that included the Internet/Computer Use Questionnaire, the Ego Identity Process Questionnaire, and the Rosenberg Self Esteem Scale. Racial differences were found between Black and White females with regard to perceived problematic use of the Internet and use of the computer for communication and use of the Internet for schoolwork. In addition, differences between Black and White females were found between identity formation and problematic use of the Internet and between self-esteem and type of use of the Internet. These findings were discussed in relation to future research and interventions.     

Degradation of junction leakage in devices subjected to gateoxidation in nitrous oxide [MOS transistors]

Nitrided gate oxides offer several electrical and reliability advantages over conventional oxides and also provide a good barrier against impurity diffusion. Oxidation in nitrous oxide (N₂O) has been very successful in overcoming some of the problems associated with nitridation in ammonia. The authors have observed that the extent of N₂O oxidation has a strong detrimental effect on the drain leakage current of MOS transistors in the off state. This phenomenon has been identified to be caused by an increase in the active area junction leakage current     

Applicant reactions to face-to-face and technology-mediated interviews: A field investigation.

This field study examined applicant reactions (N = 802) toward face-to-face as compared with technology-mediated interviews (through videoconferencing or by telephone) for 346 organizations. Face-to-face interviews were perceived as more fair and led to higher job acceptance intentions than were videoconferencing and telephone interviews. Perceived interview outcomes were higher with face-to-face and telephone interviews over videoconferencing. Self-monitoring moderated the relationship between interview medium and perceptions of fairness. Specifically, this relationship was (a) positive for face-to-face, (b) negative for telephone, and (c) nonsignificant for videoconferencing interviews. Moreover, the number of offers an applicant received moderated the relationship between interview medium over, and perceived fairness. The relationship between number of offers and perceived fairness was positive for face-to-face and negative for technology-mediated interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydrogen Resistance of Steels Alloyed with Nitrogen

We study the resistance of stainless steels with different contents of nitrogen after plasma-arc remelting to hydrogen degradation. The dependence of the mechanical properties of steels on the content of nitrogen is quite complicated, which is explained by changes in the phase composition. In the analyzed collection of steels (Kh18AN9, Kh20AN15, Kh18AG10, and Kh18AG15), Kh18AG15 steel has the best combination of the characteristics of strength and plasticity in hydrogen.     

Association between inflammatory bowel disease and sarcoidosis. Report of two cases and review of the literature

BACKGROUND: Common etiopathogenic factors may explain the association of systemic sarcoidosis with inflammatory bowel disease. METHODS: We report two cases of such an association: one of sarcoidosis that developed 2 years after proctocolectomy for ulcerative colitis and one of sarcoidosis and Crohn's colitis. Factors like increased cellular immunity or circulating immunocomplexes or autoantibodies may have a role. Exogenous agents or familiarity may also be involved. CONCLUSIONS: It is postulated that the association between sarcoidosis and inflammatory bowel disease (both ulcerative colitis and Crohn's disease) does not occur by chance alone and that the two conditions may share some genetic or immunologic alterations. The two diseases, however, follow an independent clinical course.