Effects of rising temperatures and [CO2] on the physiology of tropical forest trees

Using a mixture of observations and climate model outputs and a simple parametrization of leaf-level photosynthesis incorporating known temperature sensitivities, we find no evidence for tropical forests currently existing ‘dangerously close’ to their optimum temperature range. Our model suggests that although reductions in photosynthetic rate at leaf temperatures (TL) above 30°C may occur, these are almost entirely accountable for in terms of reductions in stomatal conductance in response to higher leaf-to-air vapour pressure deficits D. This is as opposed to direct effects of TL on photosynthetic metabolism. We also find that increases in photosynthetic rates associated with increases in ambient [CO2] over forthcoming decades should more than offset any decline in photosynthetic productivity due to higher D or TL or increased autotrophic respiration rates as a consequence of higher tissue temperatures. We also find little direct evidence that tropical forests should not be able to respond to increases in [CO2] and argue that the magnitude and pattern of increases in forest dynamics across Amazonia observed over the last few decades are consistent with a [CO2]-induced stimulation of tree growth

Supporting the library and information needs of UWE health and social care students on placement

© 2017 Health Libraries Group Objective: The aim of this research was to explore the library and information needs of health and social care students whilst on placement. Methods: Both desk and primary research were conducted and included an online questionnaire to students and semi-structured interviews. Results: The questionnaire was completed by 252 students from a variety of programmes, equivalent to a 10% response rate. The results indicate a wide range of factors impacting on the library and information experiences of students. Whilst differences in the availability of a physical library in hospital or community locations still exist, these are mitigated by technology and a preference for home study. A significant result is that 77% (n=193) of students on placement study at home, using a variety of Internet-connected devices. This highlights a marked change in practice and underlines the need for mobile-compliant e-resources and accessible at-a-distance services. Conclusion: As a result of this research, practical recommendations on how library support can be improved were developed including enhanced collaboration and learning with NHS colleagues, and knowledge sharing with other departments within the University who support our students

Individual Responses to an 8-Week Neuromuscular Training Intervention in Trained Pre-Pubescent Female Artistic Gymnasts

This study examined individual responses in leg stiffness, reactive strength index (RSI), movement proficiency (deep overhead squat and in-line lunge), and trunk muscular endurance (flexor and extensor tests) in young female gymnasts following an 8-week neuromuscular training intervention. Thirty-four pre-peak height velocity (PHV) female gymnasts were divided into either an experimental group (EXP n = 17) or control group (CON n = 17). The EXP replaced their normal gymnastics physical preparation with a neuromuscular training program, while the CON continued with their habitual gymnastics program. Chi square analysis showed that the EXP resulted in significantly more positive responders compared to CON for measures of leg stiffness (41% versus 12% responded positively), extensor muscular endurance, (76% versus 29%), and competency in the deep overhead squat, (76% versus 29%) and in-line lunge (left lead leg) (65% versus 18%). Conversely, the number of positive responders for RSI (53% versus 61%), the flexor endurance test (88% versus 53%), and the right in-line lunge (47% versus 35%) were not significantly different between groups. These findings suggest that most young gymnasts responded positively to neuromuscular training from the perspective of improving movement proficiency and trunk endurance; however, changes in leg stiffness and RSI were more variable and may require higher intensities to realise further adaptations

The Longitudinal Development of Movement Competency in Young High-Level Golfers

The aim of this study was to longitudinally monitor movement competency of golfers in a talent development program. Thirty-six golfers were included in the study (24 males, 12 females); on entry the mean age was 14.38 ± 2.88 years and mean handicap was 6. Participants completed the Golf Movement Screen (GMS). Data was collected annually at the start of each off-season in the program, providing three testing occasions over a two-year period. Total GMS score significantly improved (all p < 0.05) year-on year from 41 ± 13 on entry, to 52 ± 13 in year 1, and 63 ± 14 in year 2. Handicap also significantly improved from 6 ± 5 on entry to 2 ± 4 in year 2 (p < 0.05). Significant improvements were found in 7 of the 10 exercises between entry and year 1, and 9 of the 10 exercises between entry and year 2 (all p < 0.05), while scores for the remaining exercise were high on entry and remained stable. The findings suggest that golfers in a talent development program are able to improve their movement competency, and that the GMS has the sensitivity to detect these changes

Comparison of the Effect of Caffeine Ingestion on Time to Exhaustion between Endurance Trained and Untrained Men

This study compared the ergogenic effects of caffeine on men who were endurance trained to those who were untrained. The study was a double-blind, placebo-controlled crossover experimental design. Ten endurance trained men (mean age 24.4 ± 2.0 yrs, weight 79.4 ± 8.5 kg, predicted VO2 max 46.3 ± 1.8 mL·kg-1·min-1) and 10 untrained men (mean age 22.8 ± 1.9 yrs, weight 88.9 ± 9.9 kg, predicted VO2 max 37.6 ± 2.7 mL·kg-1·min-1) completed two cycle ergometer trials to exhaustion at 80% of their predicted workload max 30 min after ingesting either 5 mg·kg-1 of body weight of caffeine or a placebo. Neither group displayed significant increases in time to exhaustion (Trained Group: 786.4 ± 251.5 sec for the placebo trial and 810.7 ± 209.4 sec for the caffeine trial and the Untrained Group: 514.6 ± 107.8 sec for the placebo trial and 567.3 ± 140.5 sec for the caffeine trial) after ingesting caffeine. When compared statistically between groups, the difference was not significant. When the groups were combined, the difference was caffeine and the placebo was not significant. The findings indicate that there was no ergogenic effect of caffeine on time to exhaustion in either endurance trained or untrained men

Bio-banding in Sport: Applications to Competition, Talent Identification, and Strength and Conditioning of Youth Athletes

Bio-banding is the process of grouping athletes on the basis of attributes associated with growth and maturation, rather than chronological age. Children of the same age may vary considerably in biological maturation with some individuals maturing well in advance or delay of their peers. The timing of maturation has important implications for competition, talent identification and training. Increased awareness and interest in the subject of maturation has sparked a renewed interest in the study and application of bio-banding. This overview describes the purpose and process of bio-banding, potential benefits and limitations, and also presents some recent advances in its application in youth sports

Near-future level of CO2-driven ocean acidification radically affects larval survival and development in the brittlestar Ophiothrix fragilis

The world's oceans are slowly becoming more acidic. In the last 150 yr, the pH of the oceans has dropped by similar to 0.1 units, which is equivalent to a 25 % increase in acidity. Modelling predicts the pH of the oceans to fall by 0.2 to 0.4 units by the year 2100. These changes will have significant effects on marine organisms, especially those with calcareous skeletons such as echinoderms. Little is known about the possible long-term impact of predicted pH changes on marine invertebrate larval development. Here we predict the consequences of increased CO2 (corresponding to pH drops of 0.2 and 0.4 units) on the larval development of the brittlestar Ophiothrix fragilis, which is a keystone species occurring in high densities and stable populations throughout the shelf seas of northwestern Europe (eastern Atlantic). Acidification by 0.2 units induced 100 % larval mortality within 8 d while control larvae showed 70 % survival over the same period. Exposure to low pH also resulted in a temporal decrease in larval size as well as abnormal development and skeletogenesis (abnormalities, asymmetry, altered skeletal proportions). If oceans continue to acidify as expected, ecosystems of the Atlantic dominated by this keystone species will be seriously threatened with major changes in many key benthic and pelagic ecosystems. Thus, it may be useful to monitor O. fragilis populations and initiate conservation if needed

Laser Peening to Improve Fatigue Strength and Lifetime of Critical Components1

AbstractFatigue failure is typically driven by component geometric requirements that result in local areas of high tensile loading stress. Within this paper we discuss the deep protective stress generated by laser peening and show examples of using a newly developed finite element predictive strain and stress tool that accurately models laser peening. The analysis tool and robust process enable the accurate engineering of local compressive stress into critical areas of diverse/all(?) ferrous and non-ferrous materials in a well-defined manner that significantly improves fatigue life and strength. This capability opens the potential for advanced designs with increased performance, enhanced reliability and reduced system weight

Asymmetry During Maximal Sprint Performance in 11- to 16-Year-Old Boys

Purpose: The aim of this study was to examine the influence of age and maturation upon magnitude of asymmetry in the force, stiffness and the spatiotemporal determinants of maximal sprint speed in a large cohort of boys. Methods: 344 boys between the ages of 11 and 16 years completed an anthropometric assessment and a 35 m sprint test, during which sprint performance was recorded via a ground-level optical measurement system. Maximal sprint velocity, as well as asymmetry in spatiotemporal variables, modeled force and stiffness data were established for each participant. For analysis, participants were grouped into chronological age, maturation and percentile groups. Results: The range of mean asymmetry across age groups and variables was 2.3–12.6%. The magnitude of asymmetry in all the sprint variables was not significantly different across age and maturation groups (p > .05), except relative leg stiffness (p < .05). No strong relationships between asymmetry in sprint variables and maximal sprint velocity were evident (rs < .39). Conclusion: These results provide a novel benchmark for the expected magnitude of asymmetry in a large cohort of uninjured boys during maximal sprint performance. Asymmetry in sprint performance is largely unaffected by age or maturation and no strong relationships exist between the magnitude of asymmetry and maximal sprint velocity