Response of males and females to high-force eccentric exercise

It has previously been shown that females incur less muscle damage than males after strenuous exercise, but limited data are available for humans. To determine possible differences between the sexes in humans, the response to high-force eccentric exercise was examined in a large sample of women (n = 83) and men (n = 82). The participants performed a bout of eccentric exercise of the elbow flexors consisting of 70 maximal repetitions. Isometric strength, resting elbow angle and muscle soreness were measured before, immediately after (except soreness) and then daily for 7 days after exercise. There was a significant loss in strength among both groups (69% for women and 63% for men) (P < 0.01) immediately after exercise; at 168 h post-exercise, women still had a 27% strength loss and men had a 24% strength loss. No significant difference in strength loss or recovery rate was found between men and women. Soreness reached peak values 32-48 h post-exercise (P < 0.01), with no significant difference between men and women. Range of motion decreased significantly until 3 days after exercise (14.6 degrees or 0.255 rad loss for women; 12.2 degrees or 0.213 rad loss for men) (P < 0.01); at 168 h post-exercise, the women and men still showed a loss of 4.8 degrees (0.084 rad) and 4.0 degrees (0.07 rad), respectively. There was a significant interaction of sex x time (P < 0.01); a post-hoc test indicated that the women experienced a greater loss in range of motion at 72 h than men and this difference was maintained to 168 h post-exercise (P < 0.01). Thus, our results do not support the contention that women have a lower response to eccentric exercise than men.     

Physiological Responses to Maximal Treadmill and Handweighted Exercise

Abstract

The purpose of this investigation was to compare the peak physiological responses among four protocols that employed different amounts of handweighted exercise in 16 males (aged 26.3 ± 4.1 years). The four protocols were (a) uphill treadmill running (UR; 3.36 m-s¹, 2.5% grade increase-3 min¹); (b) uphill treadmill walking while pumping 1.36kg handweights (HW) (UWHW; 1.79ms¹, 5.0% grade increase-3 min¹; (c) treadmill walking while pumping .91-kg HW (WHW; 1.79 m-s¹, 0% grade, .91kg HW increase-3 min¹); and (d) standing in place and pumping HW (SHW; arm work as described in WHW). It was hypothesized that the peak responses would be inversely proportional to the estimated muscle mass activated (i.e., UR = UWHW > WHW > SHW). Dependent variables included peak oxygen uptake (VO₂ peak), peak heart rate (HRpeak), peak ventilation (V_epeak), and peak respiratory exchange ratio (RERpeak). No differences were noted between UR and UWHW with respect to any of the dependent variables. All variables (except RERpeak) were greater (p < .01) in UR and UWHW than either WHW or SHW. RERpeak was greater (p < .01) in UR and UWHW than in WHW. VO₂peak and HRpeak were greater (p < .01) in WHW when compared to SHW. Mean VO₂peak was 97.5, 69.7, and 60% of UR for UWHW, WHW, and SHW, respectively. Therefore, walking and pumping handweights provides a maximal stimulus to the oxygen transport system.     

Online interaction across three contexts: an analysis of culture and technological affordances

Students were linked virtually across three contexts: U.S., Malaysia, and China. Differences emerged in how student-created messages were constructed and interpreted; these impacted perceived relational affiliation. Messages constructed by students in Malaysia and China exhibited casual talk, greater self-disclosure, requests for personal information, and greater use of emoticons/emoji. Interactions were perceived as informal, friendly, and positive. U.S. students’ messages often showed institutional talk, less self-disclosure, and more attention to the instructor-assigned task. Asian-U.S. student pairs perceived their interactions as formal, less friendly, and less positive. This study shows how online technologies may be afforded and shaped by culture and interaction.     

Global exact tracking for uncertain MIMO linear systems by output feedback sliding mode control

This paper presents a solution to the problem of global exact output tracking for uncertain MIMO (multiple-input–multiple-output) linear plants with non-uniform arbitrary relative degree using output feedback sliding mode control. The key idea to overcome the relative degree obstacle is to generalize our previous hybrid estimation scheme to a multivariable version by combining, through switching, a standard linear lead filter with a non-linear one based on robust exact differentiators, achieving uniform global exponential practical stability and exact tracking.     

Beyond the online catalog: developing an academic information system in the sciences

The online public access catalog consists essentially of a machine-readable database with network capabilities. Like other computer-based information systems, it may be continuously enhanced by the addition of new capabilities and databases. It may also become a gateway to other information networks. This paper reports the evolution of the Bibliographic Access and Control System (BACS) of Washington University in end-user searching, current awareness services, information management, and administrative functions. Ongoing research and development and the future of the online catalog are also discussed.     

Customer prioritization in higher education: targeting ‘right’ students for long-term profitability

As competition for students, faculty and financial support has increased, so has the application of marketing in the field of higher education. One critical application of marketing all too often neglected, misunderstood and mismanaged in higher education is targeting customers for profitability. The purpose of this paper is to enrich the marketing practices of academic institutions as they face increasing competition for students, faculty and funding by presenting a discussion of ‘right,’ ‘at-risk right’ and ‘wrong’ customers for higher education. This paper reviews marketing paradigms as they have evolved over time, explains the concepts of right, at-risk right and wrong customers as they apply to higher education and identifies managerial implications critical to today's higher education administrators.     

Adaptations in the teaching of composition to non-native speakers of English

This article defines the problem of teaching foreign students in standard American university composition courses. It describes how two composition courses were modified to meet the needs of students who were beyond English as a Second Language composition but not yet ready for mainstream study. The article suggests that adaptations, not only in technique, but in approach and content as well, are required in order to fulfill the needs of these special students.Sally L. Chirinos, M.A. was the Academic Director of the EFL Program at the Instituto Cultural Peruano-Norteamericano, Arequipa, Peru from 1977–78. Suellen Rundquist is a M.A. candidate in Foreign Language Education and English as a Second Language at the University of Minnesota. Lisa Washburn holds a M.A. in English as a Second Language and a M.A. Germanic Philology from the University of Minnesota.     

Influence of conspecific and predatory Stressors and their associated odors on defensive burying and freezing responses

In Experiment 1, male rats were exposed to either aggressive (i.e., alpha) or nonaggressive conspecific colonies and tested 24 h later, with or without alpha odors, for freezing behavior and burying of a wall prod that had been the source of a brief electric shock. The results indicated that prior defeat experience and the presence of alpha odors alone during testing had no significant effects, but the combination of prior defeat and alpha-odor testing significantly decreased burying and increased freezing behavior. In Experiment 2, we examined the effects of noncontact exposure to a cat, as a predatory Stressor, during subsequent prod-shock tests involving the presence or absence of cat odors. Exposure to a cat failed to disrupt later prod burying and did not produce freezing. However, the presence of cat odors during testing significantly reduced the amount of defensive burying,without resulting in an increment in freezing. In Experiment 3, rats were given 1, 5, or 30 inescapable preshocks in the presence of either cat odors or a hedonically neutral citronella odor and were tested 24 h later for prod burying and freezing with or without these odors. Both the cat and the citronella odors resulted in a significant reduction in burying and an increase in freezing for rats given 5 and 30 preshocks and tested in the presence of these respective conditioned odors. For the groups that were given 5 preshocks, preshock and later testing in the presence of cat odors resulted in significantly less prod burying and more freezing than for rats that were preshocked and tested in the presence of citronella. The findings of these three ethoexperimental studies are discussed in terms of the learned-helplessness theory, the stress-coping-fear-defense (SCFD) theory, and the concept of selective CS-US associability.     

Adoptive Gay Father Families: A Longitudinal Study of Children’s Adjustment at Early Adolescence

Findings are presented from the second phase of a UK longitudinal study of 33 gay father, 35 lesbian mother, and 43 heterosexual parent families when their adopted children reached early adolescence. Participants predominantly lived in urban/suburban areas and were mostly white and well-educated. Standardized interviews, observations, and questionnaires of parental mental health, parent–child relationships, and adolescent adjustment were administered to parents, children, and teachers between 2016 and 2018. There were few differences between family types. However, adjustment problems had increased in all family types, with better parenting quality and parental mental health associated with fewer adjustment problems. The findings contribute to adoption policy and practice, and to theoretical understanding of the role of parental gender in child development.