Influence of the initial projection of the centre of gravity on posturo-kinetic coordination in humans. Application from a horizontal quadrupedal stance during voluntary limb raising

The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase.     

Center of Gravity Motions and Ankle Joint Stiffness Control in Upright Undisturbed Stance Modeled Through a Fractional Brownian Motion Framework

The authors modeled the center of gravity vertical projection (CG_V) and the difference, CP - CG_V, which, combined, constitute the center of pressure (CP) trajectory, as fractional Brownian motion in order to investigate their relative contributions and t heir spatiotemporal articulation. The results demonstrated that CG_V and CP - CG_V motions are both endowed in complementary tashion with strong stochastic and part-deterministic behaviors. In addition, if the temporal coordinates remain similar for all 3 trajectories by definition, the switch between the successive control mechanisms appears for shorter displacements for CP - CG_V and CG_V than for CP trajectories. Results deduced from both input (CG,) and muscular stiffness (CP - CG_V) thus provide insight into the way the central nervous system regulates stance control and in particular how CG and CP - CG are controlled.     

Comprehension of the Referential Intent of Looking and Pointing Between 12 and 15 Months

Butler, Caron, & Brooks (2000) tested the gaze following of 14-and 18-month-olds under 3 conditions: (1) when the adult's view of the targets was blocked by barriers, (2) when the barriers contained open windows, and (3) no barriers. Contrary to a nonmentalist "ecological" model (adult turns serve as cues to the location of interesting events), frequency of gaze following by 14-month-olds was not equivalent across the 3 conditions. Contrary to a mentalist model (infant wants to see what the adult is seeing), gaze following was not substantially less in the barrier than in the window and no-barrier conditions (as was the case for 18-month-olds). To examine whether the barriers posed vector projection problems for essentially nonmentalist, or line-of-sight problems for essentially mentalist younger infants, 3 experiments were conducted. In Experiment 1, a 12-month group was tested in the same 3 conditions to determine if, being younger, they might yield a more clearcut nonmentalist pattern. Contrarily, they behaved like Butler et al.'s 14-month-olds. In Experiment 2, a 14-month group was tested in the barrier and window conditions, but now combining pointing with turning. Infants behaved as predicted by the mentalist model: strong responding in the window condition and minimal in the barrier (where many strained to look inside the partitions). In Experiment 3, an attempt was made to differentiate between mentalist and "geometric" (vector projection) interpretations of the results of Experiment 2 by testing another 14-month group with the adult's eyes closed while pointing. Gaze following now dropped precipitously in the window condition as did looking inside the solid barriers, indicating (1) that infants in Experiment 2 had not simply been guided to target by an extended arm, but construed it as part of a referential act that was as much visual as gestural, and (2) that by 14 months, infants may have acquired a mentalistic concept of seeing.     

A Feminist Analysis of Seventeen Magazine: Content Analysis from 1945 to 1995

This study is an extension of the contentanalysis conducted by K. Peirce [(1990) AFeminist Theoretical Perspective on the Socialization ofTeenage Girls Through Seventeen Magazine, SexRoles, Vol. 23, pp. 491-500]. Her study examined thecontent of Seventeen magazine for the years 1961, 1972,and 1985, and the impact of the feminist movement fromthe 1960s through the 1980s. The present study explored the content of Seventeen magazine in the years1945, 1955, 1965, 1975, 1985, and 1995 to determine ifthe articles that are presented have changed in responseto the feminist movement from the 1940s to the present day. These results would supportthe contention that there is a relationship between thecontent of Seventeen magazine, in terms of traditionalvs. feminist messages, and the women's movement. However, these changes are slight and still donot reflect the various roles of teenage girls.Implications for further research arediscussed.     

A Qualitative Analysis of Home‐Based Counselors' Experiences in a Rural Setting

This qualitative study sought to understand the experiences of home‐based counselors working in a rural setting. In‐depth interviews were conducted with 12 counselors who were asked to describe their experiences in the areas of preparedness, professional development, challenges, and gender‐specific experiences. Fourteen coding categories emerged from the interviews, which led to the findings of 3 overarching themes: shared isolation, ethical ambiguity, and the high‐intensity nature of the job. Recommendations for home‐based counselors, agencies, and professional counseling associations are discussed.     

Ties that Bind: A Qualitative Study of Happy Long-Term Marriages

An abundance of literature exists concerning the marital relationship. While most research focuses on divorce and the social consequences of this phenomenon, more recently social scientists have focused on the marriages that remain intact. The purpose of this study was to gain insight into what factors make marriages last. This study used qualitative methodology to gain further insight into long-term marriages. Interviews were conducted with 15 heterosexual couples who had been married for at least 35 years and who identified their marriage as happy. Results indicate that for each couple the factors contributing to the longevity of their happy marriage were numerous and unique. While the most commonly mentioned factors included friendship, love, and similar backgrounds or interests, a wide range of responses were elicited.     

Evaluating the effectiveness of workshop interventions on contraceptive use among first-year college students

This study tested the effectiveness of 4 interventions designed to affect contraceptive knowledge, attitudes, and use among first-year Syracuse University students in New York State in the US. Pre- and post-tests obtained data on demographic characteristics, sexual behavior, contraceptive knowledge, sexual opinions, contraceptive attitudes, and contraceptive progress on a 5-step scale. Group 1 (79 students) received contraceptive information (CI) only. Group 2 (76) received CI and a cognitively oriented intervention. Group 3 (73) received CI and an experience-oriented intervention. Group 4 (77) received a combined cognitively and experience-oriented intervention with CI. The control group included 57 people. 78% on the pretest, and 84% on the post-test, had engaged in sexual intercourse for the first time in high school. 200 indicated previous intercourse in the past 3 months. Groups varied significantly in their knowledge, beliefs, and practices. All groups had greater contraceptive knowledge than control groups. Greater behavior beliefs about contraceptive use occurred in Groups 1 and 2. Groups 3 and 4 showed greater increases in positive attitudes toward use. All intervention students showed greater increases in positive attitudes toward a contraceptive process. Greater increases in the intention to use birth control occurred in Groups 3 and 4. Groups 2, 3, and 4 showed greater increases in reported use of birth control. Group 4 intervention was the most effective for males. Females were influenced by all interventions. Findings affirm the importance of including attitudinal components in sexuality and contraception workshops.