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Biomedical subjects

R M Lerner

Publications and source records attributed to R M Lerner.

At least 19 recordsLinked to original sources
PubMed1999

Does self-competence predict gender differences in adolescent depression and anxiety?

This longitudinal study examined 75 young adolescents to explore whether self-competence predicts the emergence of gender differences in depression and anxiety. During both 6th and 7th grade, boys reported significantly higher levels of self-competence than did girls. In addition, boys were significantly less depressed and anxious than girls in 7th grade, but not in 6th grade. Finally, when the variance contributed by self-competence was accounted for, the relationship between gender and trait anxiety weakened and the relationship between gender and depression became non-significant. These results support the hypothesis that self-competence is partially responsible for the emergence of gender differences in depression and anxiety during early adolescence.

Adaptation, Psychological↗
PubMed1998

Perceived parental acceptance and early adolescent self-competence.

Relationships between perceived parental acceptance and adolescent self-competence were examined in 214 sixth- and seventh-grade students by both adolescent and parental gender. Results indicated that for boys, paternal but not maternal, acceptance significantly predicted self-competence, while the opposite pattern was found for girls. In addition, self-worth significantly predicted maternal and paternal acceptance for both boys and girls. The consistency of these findings with current models of human development is discussed, along with their implications for research.

Adolescent↗
PubMed1998

Adolescent development: challenges and opportunities for research, programs, and policies.

The basic process of adolescent development involves changing relations between the individual and the multiple levels of the context within which the young person is embedded. Variation in the substance and timing of these relations promotes diversity in adolescence and represents sources of risk or protective factors across this life period. The key risk factors of the contemporary American adolescent period are discussed. Behavioral risks involve drug, alcohol, and substance use and abuse; unsafe sex, teenage pregnancy, and teenage parenting; school underachievement, failure, and dropout; and delinquency, crime, and violence. Poverty among youth exacerbates these risks. The features of youth programs effective in preventing the actualization of risk or in promoting positive adolescent development are discussed, as are the characteristics of public policies that may enhance the life chances of the diverse youth of America and the world.

Adolescent↗
PubMed1996

Imaging of the elastic properties of tissue--a review.

Recently, a number of methods have been developed that make it possible to image the elastic properties of soft tissues. Because certain types of tissues such as malignant lesions, for example, have elastic properties that are markedly different from surrounding tissues, elasticity imaging could provide a significant adjunct to current diagnostic ultrasonic methods. Further, elasticity imaging techniques could be used to augment the study of tissues that change their elastic properties, such as skeletal and cardiac muscle. In this paper, we survey some of the previous work done in the related field of biomechanics, and we review measurement techniques from the 1950s to the 1980s. Different approaches to elastic imaging and signal processing are then discussed and a lexicography for elastic imaging is introduced. It is hoped that this nomenclature will provide a meaningful categorization of various approaches and will make evident the inherent parameters displayed and conditions applied in deriving the resulting images. Key assumptions and signal processing approaches are also reviewed. Finally, directions for future work are suggested.

Animals↗
PubMed1994

Continuity and discontinuity in the affective experiences of parents and children: evidence from the New York Longitudinal Study.

Canonical correlation described continuity and discontinuity in salient covariates of emotional and interactional components in parent-child relationships among NYLS participants from middle adolescence to young adulthood. The results underscore the importance of multiple indicators of parent-child relationship quality, and their implications for assessment and intervention efforts are discussed.

Adaptation, Psychological↗
PubMed1992

Temperament and adjustment in young adulthood: a 15-year longitudinal analysis.

The relationship between easy/difficult temperament and adjustment from middle adolescence to young adulthood was examined. Cluster analysis revealed four groups of individuals via composite temperament scores over three points of measurement. Multivariate analyses indicated that extremely difficult temperament was associated with poorer psychosocial functioning in childhood and young adulthood.

Adaptation, Psychological↗
PubMed1992

Sonographic measurement of diaphragmatic motion after coronary artery bypass surgery.

Forty-eight patients were prospectively evaluated following coronary artery bypass grafting (CABG) in order to determine values for diaphragmatic mobility by sonography, to compare diaphragmatic motion to chest x-ray findings, to relate diaphragmatic motion to pulmonary function tests, and to determine whether use of the left internal mammary artery (LIMA), aortic cross-clamp time, or other clinical variables were predictive of diaphragmatic dysfunction. Mean left diaphragmatic motion was 2.8 +/- 1.1 cm (range, 1.0 to 5.7 cm), mean right diaphragmatic motion was 3.9 +/- 1.1 cm (range, 1.8 to 6.4 cm), and ratio of left to right motion was 0.74 +/- 0.27 (range, 0.19 to 1.4). Forty-one patients had normally positioned diaphragms on the chest x-ray film; four of these had poor mobility by ultrasonography (< 1.6 cm). Of the seven elevated left hemidiaphragms on chest x-ray films, three had an excursion of 1.6 cm or more by ultrasonography. The mean FVC for all patients was 59 +/- 13 percent of predicted. There was no relationship between diaphragmatic mobility and FVC or negative inspiratory pressure. The diaphragmatic motion in 36 patients having LIMA grafting was similar to those without (2.7 +/- 1.2 cm [n = 36] vs 2.8 +/- 0.8 cm [n = 12], respectively). Aortic cross-clamp time and respiratory symptoms also did not correlate with diaphragmatic mobility. Sonography can be used in the evaluation of diaphragmatic motion after CABG and may be more accurate in detecting a poorly mobile diaphragm than is the chest x-ray film.

Coronary Artery Bypass↗
PubMed1992

Sonoelasticity of organs: shear waves ring a bell.

Sonoelasticity is the use of ultrasonography to visualize, in real time, the hardness of stiffness of tissues and organs by depicting the tissue's motion in response to an applied vibration source. The applied vibration source is usually of low amplitude and low frequency (less than 0.1 mm displacement and less than 2000 Hz). Under these conditions, the natural vibration response of tissues and whole organs is revealed as a standing wave pattern determined by the low-frequency elastic constants of the tissues and their boundary conditions, factors that are not related to the ultrasonic echogenicity. As a result, hard or dense isoechoic tumors that are undetectable by conventional ultrasonography often can be visualized in sonoelasticity imaging by virtue of their altered vibration response. In this report, we demonstrate the appearance of organs such as the breast, liver, and kidney during real-time, in vivo sonoelasticity imaging. The results show that the shape and location of vibration patterns are dependent on the tissues and vibration frequencies; thus, information about the basic elastic properties of tissues should be obtainable.

Breast↗
PubMed1991

Color Doppler ultrasound compared to a radionuclide scanning of spermatic cord torsion in a canine model.

High resolution color doppler ultrasound can simultaneously display blood flow superimposed on detailed gray scale anatomic images. Using a single-blind study design, nine adult male dogs underwent intravaginal spermatic cord torsion and subsequent evaluation with technetium 99M-pertechnetate radionuclide, and color doppler ultrasound imaging techniques. Torsions of 90 to 720 degrees were created surgically, followed by examination with each modality at one hour (four animals), and four hours (five animals) following the procedure. Testicular torsion was diagnosed if perfusion was absent or markedly diminished on color doppler imaging or radionuclide scan. In all cases of 360 degrees or greater, torsion was diagnosed by either modality at both one and four hour time delays. If observers did not diagnose torsion, they were asked to assess the relative testicular perfusion. Color doppler ultrasound and radionuclide scanning were without error in correctly detecting a relative decrease in perfusion in each of these instances. Furthermore, color doppler imaging with spectral analysis was able to detect an enhancement of the diastolic component of the arterial signal at 180 degrees of torsion. This spectral pattern coupled with a relative decrease in blood flow allowed presumptive diagnosis at one hour of partial torsion that was subsequently apparent as absent perfusion only after 4 hours on radionuclide and repeat color doppler ultrasound. Color doppler ultrasound proved to be superior to radionuclide scanning in detecting diminished perfusion in this experiment. The detailed information provided by spectral and anatomic display with color doppler ultrasound recommends it for the evaluation of acute scrotal pathology of uncertain etiology.

Animals↗
PubMed1991

Sonoelasticity imaging: results in in vitro tissue specimens.

The authors present a method for imaging tissue stiffness (sonoelasticity) that has been developed and tested in a laboratory setting by using in vitro canine and human prostate glands. A low-frequency acoustic source was used to induce vibration in tissue under examination, and a color Doppler ultrasound (US) instrument was modified to detect vibration amplitude. The resulting image is a color "map" of tissue vibration superimposed on conventional gray-scale US images. Stiffer tissues vibrated less in response to audible sound, regardless of echogenicity. Normal human and canine prostate glands demonstrated a uniform vibration pattern. Four of four human prostatic adenocarcinomas and two stiff inclusions injected into canine prostate glands demonstrated a lack of vibration in comparison with normal surrounding tissue. The authors conclude that while further study is necessary, sonoelasticity imaging may enhance the detection of neoplasms by enabling their identification solely on the basis of stiffness.

Adenocarcinoma↗
PubMed1991

Testicular imaging.

Clinicians have relied on radionuclide scanning for evaluating acute scrotal pain and on ultrasonography for chronic scrotal pain and anatomic lesions (testicular and paratesticular structures). This review reinforces the utility of these established imaging techniques and also introduces color Doppler ultrasonography as an integral component in the advancement of testicular imaging, particularly in effective and timely diagnosis of spermatic cord torsion. The expanding capability of MR imaging for scrotal disorders is presented.

Color↗
PubMed1990

Relations among early adolescent temperament, parent and peer demands, and adjustment: a test of the goodness of fit model.

This study assessed whether the goodness of fit--between early adolescents temperaments and their parents and peers demands, or "ethnotheories", regarding temperament--was more related to adjustment than were acontextual measures of temperament alone. Data from the Pennsylvania Early Adolescent Transitions Study, a short-term longitudinal investigation of 153 adolescents from the beginning of sixth grade to the end of seventh grade, were used. Temperament was indexed by the nine attributes measured by the Revised Dimension of Temperament Survey, and the measures of demands regarding temperament were derived from different versions of this instrument. Adjustment was indexed by teacher ratings of academic and social competence and by parent ratings of problem behaviors. At the end of Grade 6 and the beginning of Grade 7, the number of significant relations between the adjustment measures and the fit scores tended to be greater than the number of significant relations between adjustment and temperament, measured alone. Moreover, groups formed on the basis of high vs. low temperament fit showed differential adjustment scores: adolescents in the low fit group in regard to both peer- and parent-demands received lower teacher ratings of scholastic competence, and higher parent ratings for conduct and school problems, than did the adolescents in the high fit group.

Child↗