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We carefully investigate three important effects including postgrowth activation annealing, delta ({\delta}) dose and p+-GaN layer thickness and experimentally demonstrate their influence on the electrical properties of GaN p-n homojunction diodes with a tunnel junction (TJ)-based p-contact. The p-n diodes and TJ structures were monolithically grown by metalorganic chemical vapor deposition (MOCVD) in a single growth step. By optimizing the annealing time and temperature for magnesium (Mg) activation and introducing {\delta}-doses for both donors and acceptors at TJ interfaces, a significant improvement in electrical properties is achieved. For the continuously-grown, all-MOCVD GaN homojunction TJs, ultra-low forward voltage penalties of 158 mV and 490 mV are obtained at current densities of 20 A/cm2 and 100 A/cm2, respectively. The p-n diode with an engineered TJ shows a record-low normalized differential resistance of 1.6 x 10-4 {\Omega}-cm2 at 5 kA/cm2.

We report a theoretical study of the structural, electronic and optical properties of hBN-AlN superlattice heterostructures (SL) using a first-principles approach based on standard and hybrid Density Functional Theory. We consider short-period ($L<10$ nm) SL and find that their properties depend strongly on the AlN layer thickness $L_{AlN}$. For $L_{AlN}\lesssim1$ nm, AlN stabilizes into the hexagonal phase and SL display insulating behavior with type II interface band alignment and optical gaps as small as $5.2$ eV. The wurtzite phase forms for thicker AlN layers. In these cases built-in electric fields lead to formation of polarization compensating charges as well as two-dimensional conductive behavior for electronic transport along interfaces. We also find defect-like states localized at interfaces which are optically active in the visible range., Comment: 5 pages, 5 figures + Suppl. Mat., to appear in Appl. Phys. Lett

In a study of the differences in male and female descriptions of nine photographs, picture type was found to be an important variable. Twelve male and 8 female college students were asked to describe each of the photographs. Picture type was rated as high in interest to males, high in interest to females, or high in interest to both. Responses were scored for five categories of language use: word production (number of words, self-references, and color references); weakeners (self-deprecation, qualifiers such as "kind of" or "looks like"); fillers ("um,""er,""okay"); paralinguistic features (question inflection, laughter); and queries or comments to the experimenter (task-related or task-irrelevant). Picture type was found to affect length of description (shortest for female-interest pictures), color references (most for female-interest), and question intonation (most common for male-interest). The use of self-reference and self-deprecation were both associated with question intonation and laughter. Results suggest that while topic affects speech style, gender does not. (MSE)

Many linguists have maintained that the pronouns "he,""his," and "him" and the noun "man," when used in the generic sense, legitimately refer to both males and females and effectively cue readers to think of both. Others have argued, however, that the generic terms cause readers to "filter out" or dismiss females from consideration. If generic terms do function to exclude females from consideration, they might also influence memory for facts--that is, subjects who have a greater interest in the material they read are likely to recall more information than those who are less interested. A study was designed to examine the effects of generic versus female-inclusive written language on memory for factual material in male and female subjects. Twenty-eight male and 50 female college students read one of two versions of a 400-word essay, one using generic terms and the other using female inclusive terms ("he or she,""men and women," and "they"). Two days later, they completed a recall and recognition task. The results indicated that the female subjects displayed better recall of facts from their reading when the referent pronouns were female inclusive, while males showed better recall with generic masculine pronouns. (FL)

Students who enrolled in women's studies courses at a college serving mainly students from working and lower middle class backgrounds were assessed for attitudes toward women and degree of sex-typing at the beginning and end of three women's studies courses. The study was conducted over three consecutive semesters in which 41 women and 6 men completed the Attitude Toward Women (ATW) Scale and the Bem Sex Role Inventory (BSRI) during the first and last weeks of classes. In addition, individual interviews were conducted with male students during the first and last weeks of courses. Results of the BSRI showed changes in masculinity and feminity scores. Masculinity scores significantly decreased for men and increased for women who participated in women's studies classes, a change that represents decreasing sex-typing in both males and females. On the ATW Scale, attitudes toward women were liberal in both sexes (though more liberal in women) at pretesting and remained so. Structured interviews with male subjects were more sensitive than objective measures in revealing perceived changes in males. Results contribute to an understanding of attitude change as a function of exposure to information in an academic setting. (LH)

A survey of 99 female and 78 male college students regarding their attitudes toward titles of address for men (Mr.) and women (Miss, Mrs., and Ms.) had the students rate 10 concepts on 15 bipolar semantic differential scales. Nine of the concepts were neutral to the study's objectives, and the tenth was the concept of differential address for men and women. The scales used represented three universal components of affective meaning: evaluation, potency, and activity. It was found that on the evaluation scale, males and females agree that the four forms of address connote different degrees of goodness, with "Ms." receiving the lowest ratings. Comparisons showed "Ms." and "Mr." were rated lower than "Miss" or "Mrs." On the potency scale, males and females rated "Mr." lowest in potency, with "Ms." not siginificantly higher. Males rated "Mrs." significantly higher than the other three titles, while females rated "Miss" higher than the other three. On the activity measure, male and female subjects agreed that "Mr." and "Mrs." were lower in activity than "Miss" and "Ms.", with the latter receiving the highest absolute rating and "Mr." receiving the lowest. In sum, both males and females ascribed different affective meanings to the four forms of address on all three basic dimensions. However, no direct evidence was found in this study on whether these interpretations are extended to the titles' users. (MSE)