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Vg1, a member of the TGF-[Beta] family of growth factors, has been implicated in mesoderm induction and primary axis formation in Xenopus, chick and zebrafish. Mature Vg1 ligand is also able to affect left-right (LR) axis development when injected into specified blastomeres of the 16-cell Xenopus embryo. In order to identify Vg1-related genes in mouse, a primer specific for 3' sequence shared between all cloned Vg1 homologs was used in a 5' RACE reaction using e7.5 mouse embryo RNA as template. This yielded a single band of 1.3kb, that when cloned and sequenced was identical to the previously identified growth/differentiation factor 3 (mGDF3) gene. In situ hybridization revealed that mGDF3 is expressed throughout the embryonic portion of e7.0-e7.5 mouse embryos. At 0-5 somite stages, mGDF3 mRNA becomes localized to the anterior headfold region where it is sometimes found in a marked LR asymmetric distribution. As Vg1 homologs demonstrate biological function across species, we evaluated the ability of mGDF3 to affect LR development in Xenopus. To permit efficient processing of mGDF3 in Xenopus, a construct that creates a chimera that fuses the X-BMP2 proregion and tetrabasic cleavage site to the mGDF3 ligand was created. Both the chimeric XBMP/mGDF3 and native mGDF3 constructs were injected into specific cells of 16-cell Xenopus embryos. LR development was assessed by looking for reversal of heart looping. While the native construct resulted in only a background LR reversal rate of 7% , the chimeric construct, when injected into the right-sided cells, resulted in reversal in 40% of the injected embryos (26/66). This data indicates that the Vg1-related gene mGDF3 is expressed during mouse gastrulation and LR axis formation, and that it has biological effects on LR axis formation in Xenopus that resemble those observed with Vg1.

In the present study, quantitative data were collected to clarify the relationship between calling, call structure and eggs produced in a captive population of red drum Sciaenops ocellatus. Sciaenops ocellatus were held in four tanks equipped with long-term acoustic loggers to record underwater sound throughout a simulated reproductive season. Maximal sound production of captive S. ocellatus occurred when the photoperiod shifted from 13·0 to 12·5 h of light, and the water temperature decreased to c. 25° C. These captive settings are similar to the amount of daylight and water temperatures observed during the autumn, which is the primary spawning period for S. ocellatus. Sciaenops ocellatus exhibited daily patterns of calling with peak sound production occurring in the evenings between 0·50 h before dark and 1·08 h after dark. Spawning occurred only on evenings in which S. ocellatus were calling, and spawning was more productive when S. ocellatus produced more calls with longer durations and more pulses. This study provides ample evidence that sound production equates to spawning in captive S. ocellatus when calls are longer than 0·8 s and contain more than seven pulses. The fact that more calling, longer calls and higher sound pressure levels are associated with spawns that are more productive indicates that acoustic metrics can provide quantitative information on spawning in the wild. [ABSTRACT FROM AUTHOR]

Early childhood caries (ECC) is the single most common chronic childhood disease in the United States. Associated with a characteristic clinical presentation, ECC results from a culmination of risk factors, including cariogenic bacteria, inappropriate feeding practices, and social variables. It is essential that nurses become knowledgeable about ECC health promotion and prevention interventions to facilitate their efforts in everyday patient encounters and improve the overall oral health status of infants and children. This article provides an overview of ECC along with suggestions for actions that nurses can take to improve the oral health of children. [ABSTRACT FROM AUTHOR]

Examines the effect of cope geometry and e' distance on the strength and behavior of noncomposite, uniformly loaded 15 feet castellated and cellular steel beams of depths; Requirement of a large percentage reductions in the e' distance before capacity loss becomes significant; Comparison between the effect of reduced e' distance on the overall beam capacity on the cellular beams and castellated beams; Experience of failure loads by all specimens.

We discuss the construct of doubt about one's competence and suggest that doubt can have myriad consequences (e.g., self-handicapping, defensive pessimism). We focus on the effect of self-doubt when it is combined with a concern with performance and assert that this combination leads to the phenomenon of subjective overachievement. In two studies, we present a new 17-item Subjective Overachievement Scale (SOS), which includes two independent subscales measuring individual differences in self-doubt and concern with performance. The first study, consisting of two large samples (Ns = 2,311 and 1,703), provides evidence that the scale has high internal consistency and a clear two-factor structure. Additionally, the subscales have adequate test-retest reliability (Ns = 67 and 115). A second study reveals that the SOS has good convergent and discriminant validity. Both subscales are unrelated to social desirability but exhibit the predicted patterns of associations with other related constructs. The Concern with Performance Subscale is correlated with achievement motivation, whereas the Self-Doubt Subscale is correlated with scales assessing negative affectivity (e.g., self-esteem, social anxiety) and other self-related strategies associated with concerns about one's competence (e.g., self-handicapping, defensive pessimism, impostor phenomenon). The SOS, which combines the two subscales, appears to tap a unique strategy that individuals may use to deal with doubts about their own competence. [ABSTRACT FROM AUTHOR]