Sweat lactate response during cycling at 30 degrees C and 18 degrees C WBGT

Sweat lactate reflects eccrine gland metabolism. However, the metabolic tendencies of eccrine glands in a hot versus thermoneutral environment are not well understood. Sixteen male volunteers completed a maximal cycling trial and two 60-min cycling trials [30 degrees C = 30 +/- 1 degrees C and 18 degrees C = 18 +/- 1 degrees C wet bulb globe temperature (WBGT)]. The participants were requested to maintain a cadence of 60 rev min(-1) with the intensity individualized at approximately 90% of the ventilatory threshold. Sweat samples at 10, 20, 30, 40, 50 and 60 min were analysed for lactate concentration. Sweat rate at 30 degrees C (1380 +/- 325 ml x h(-1)) was significantly greater (P < 0.05) than at 18 degrees C (632 +/- 311 ml x h(-1)). Sweat lactate concentration was significantly greater (P < 0.05) at each time point during the 18 degrees C trial, with values between trials tending to converge across time. During the 30 degrees C trial, both heart rate (20, 30, 40, 50 and 60 min) and rectal temperature (30, 40, 50 and 60 min) were significantly higher than in the 18 degrees C trial. Higher sweat lactate concentrations coupled with lower sweat rates may indicate a greater relative contribution of oxygen-independent metabolism within eccrine glands during exercise at 18 degrees C. Decreases in sweat lactate concentration across time suggest either greater dilution due to greater sweat volume or increased reliance on aerobic metabolism within eccrine glands. The convergence of lactate concentrations between trials may indicate that time-dependent modifications in sweat gland metabolism occur at different rates contingent partially on environmental conditions.     

Collection development for new librarians: Advice from the trenches

There are many challenges facing new librarians in the academic environment, including collection development. This article analyzes the topic of collection development and how it relates to new professionals in the field of librarianship. The article contains a literature review of papers discussing the collection development curriculum in library and information science programs, expected skills required of collection development offices, and library training programs for new librarians. The article also provides practical advise by recent graduates and their collection development experiences. Topics of discussion include acclimation to a new environment, collection development policies and procedures, liaison work, resource selection, and time management.     

Use of the decomposition technique to test the educational screening hypothesis

The principal issue addressed in this article is whether or not education directly creates productivity and earnings as taught by traditional human capital theory. If not, an alternative argument could be that employers use education as a screening device to select employees. Employing the decomposition technique to compare income for self-employed and private sector employees, evidence is presented which rejects the screenist theory.     

Influence of bench angle on upper extremity muscular activation during bench press exercise

This study compared the muscular activation of the pectoralis major, anterior deltoid and triceps brachii during a free-weight barbell bench press performed at 0°, 30°, 45° and –15° bench angles. Fourteen healthy resistance trained males (age 21.4 ± 0.4 years) participated in this study. One set of six repetitions for each bench press conditions at 65% one repetition maximum were performed. Surface electromyography (sEMG) was utilised to examine the muscular activation of the selected muscles during the eccentric and concentric phases. In addition, each phase was subdivided into 25% contraction durations, resulting in four separate time points for comparison between bench conditions. The sEMG of upper pectoralis displayed no difference during any of the bench conditions when examining the complete concentric contraction, however differences during 26–50% contraction duration were found for both the 30° [122.5 ± 10.1% maximal voluntary isometric contraction (MVIC)] and 45° (124 ± 9.1% MVIC) bench condition, resulting in greater sEMG compared to horizontal (98.2 ± 5.4% MVIC) and –15 (96.1 ± 5.5% MVIC). The sEMG of lower pectoralis was greater during –15° (100.4 ± 5.7% MVIC), 30° (86.6 ± 4.8% MVIC) and horizontal (100.1 ± 5.2% MVIC) bench conditions compared to the 45° (71.9 ± 4.5% MVIC) for the whole concentric contraction. The results of this study support the use of a horizontal bench to achieve muscular activation of both the upper and lower heads of the pectoralis. However, a bench incline angle of 30° or 45° resulted in greater muscular activation during certain time points, suggesting that it is important to consider how muscular activation is affected at various time points when selecting bench press exercises.     

Perceived Local Job Prospects and School Connectedness in a Struggling Rural Economy: A Life-Course Perspective

Late in first decade of the 2000s, the closing of pulp and paper mills in the rural northeastern United States contributed to economic decline in the region and to rising concerns about population decline due to out-migration among local emerging adults in search of occupational or educational opportunities. In this context, and drawing on a life-course framework, the present study used four waves of panel data from the population of 7th- and 11th-grade public school students in a rural northeastern U.S. county to explore whether the county unemployment rate was related to perceived local job prospects; school connectedness was related to subsequent perceived job prospects; and the effects of county unemployment and school connectedness on perceived local job prospects varied by age cohort. Initially, changes in respondents’ perceptions about local job prospects paralleled shifts in local unemployment similarly for both cohorts; yet after the older cohort respondents had completed high school, their perceived local job prospects fell sharply, while perceptions among the younger cohort respondents, who were still in high school, remained stable. Among the older cohort respondents only, school connectedness was associated with subsequent positive perceptions about local job prospects net of relevant controls. Same-age cohort comparisons, evaluated when each cohort was in 12th-grade, showed no differences in the short-term effects of school connectedness on perceived local job prospects, despite variations in the age-linked timing of the most dramatic rise in unemployment during the study. The results highlight the lasting importance of school connectedness for teens raised in struggling rural economies.     

Greenhouse affect: the relationship between the sustainable design of schools and children’s environmental attitudes

This study aims to determine if primary school children’s environmental attitudes can be predicted by whether their school had been designed or adapted for sustainability. A New Ecological Paradigm (NEP) scale for children was adopted to measure attitudes, with supplementary questions added to align this scale to the Australian context of the study. In addition, the original adult NEP scale was used to determine relationships between children’s environmental attitudes, their School Design and their Parents’ and Teachers’ Environmental Attitudes. Data collected from grade 4, 5 and 6 primary school children, their parents and teachers were analysed via three multiple regressions. The results indicate that sustainable design in schools improves the environmental attitudes of children towards perceptibly green building features, such as solar panels, the use of recycled water, natural daylighting and outdoor classrooms including food-producing gardens.