Coherent response of lakes in Ontario, Canada to reductions in sulphur deposition: the effects of climate on sulphate concentrations

International audienceSulphate deposition in south-central Ontario declined between 1976 and 2000 by more than 50%, whereas lake sulphate (SO42?) concentrations decreased by, on average, only half as much. To investigate the factors that controlled this slower than expected response, the temporal patterns in lake SO42? concentrations were compared with patterns in both deposition and climate, since climate has a major influence on the hydrological cycle in this part of the continent. To do this, the temporal coherence in SO42? concentrations between 9 lake basins was estimated using the intraclass correlation from a repeated-measures analysis of variance and two subsets of lakes were found (six in one group, four in the other), each with lakes having synchronous patterns. One subset (4 lakes) included the 3 with the longest water replenishment times (>3.4 yr) which are expected to respond to decreases in SO42? deposition more slowly. However, the average pattern reflecting the temporal changes of each of the two subsets was very similar. The response of both subsets of lakes to the decreasing SO42? deposition over two decades was independent of the degree of acidification or sensitivity to acidification of the lakes. In a determination of which factors best predicted each of those two subsets' SO42? time series, good predictive models were produced by regional/global-scale climate indices, specifically the Southern Oscillation Index (SOI) describing the El Niño Southern Oscillation (ENSO) and the North Atlantic Oscillation Index (NAOI), as well as by SO42? deposition indices. When the predictor variables were combined, models which described the long-term changes in lake SO42? concentration best included the SOI, the NAOI and SO42? deposition. Thus, large-scale climate factors play a major role in determining the response of aquatic systems to changes in SO42? deposition, perhaps through their influence on lake and/or catchment processes that effectively delay recovery. Keywords: Atmospheric deposition, lake recovery, temporal trends, climate, temporal coherenc

The impact of broadband in schools

The report reviews evidence for the impact of broadband in English schools, exploring; Variations in provision in level of broadband connectivity; Links between the level of broadband activity and nationally accessible performance data; Aspects of broadband connectivity and the school environment that contribute to better outcomes for pupils and teachers; Academic and motivational benefits associated with educational uses of this technology

Tablet PCs in schools: Case study report: A report for Becta by the Open University

The publication provides an analysis of twelve case studies involving schools in England that were using Tablet PCs. The analysis is complemented by brief individual reports describing aspects of how each of these schools was using Tablet PCs

Thermally assisted domain walls quantum tunneling at the high temperature range

A theoretical and numerical investigations of the quantum tunneling of the domain walls in ferromagnets and weak ferromagnets was performed taking into account the interaction between walls and thermal excitations of a crystal. The numerical method for calculations of the probability of a thermally stimulated quantum depinning as the function of temperature at the wide temperature range has been evolved.Comment: 5 pages, 3 figure

Pattern formation in Turing systems with mixed boundary conditions

A central issue in developmental biology is the formation of pattern and form in the early embryo. From the apparently homogeneous mass of dividing cells that exists in the earliest stages of development emerges the vast range of pattern and structure observed in the adult. The formation of structure is termed morphogenesis, and pattern generation models are known as morphogenetic models. The role of modelling in morphogenesis is to suggest possible scenarios as to how various physical and chemical processes conspire to produce pattern

Surface temperature measurements using a thin film thermal array

A thin film device was designed and fabricated to measure surface temperatures. An array of eight integrated thermal sensors are mounted on a 0.002 inch (0.05 mm) Kapton film and multiplexed to obtain an area thermal measurement. The device was tested on a flat plate airfoil and demonstrated a temperature variation of 0.55 C maximum and 0.05 C minimum compared to embedded thermocouples. Future improvements are also discussed

The Impacts of Wrist Wrap Type and Sex on Bench Press Muscular Strength and Power

While wrist wraps have become increasingly prevalent in both competitive and recreational demographics, their posited ability to augment bench press performance by enhanced wrist stability still remains unclear. PURPOSE: To determine the effect of varying wrap styles on bench-specific muscular strength and associated power, as well as quantitative and subjective differences between sexes. METHODS: Eighteen resistance trained males and females (9M/9F; 24±4y; 176±33cm; 80±15kg) visited the laboratory on three separate occasions in randomized, crossover, and counterbalanced design to sport either a flexible wrist wrap (FW), stiff wrap (SW), or a no wrap control (NW) condition. All participants underwent a bench press one-repetition maximum (1RM) test and linear position transducer-derived peak power and velocity assessments. Furthermore, subjective stability (SS) and discomfort (SD) were determined promptly following 1RM attempts. Bench press performance and sex-collapsed subjective variables were analyzed using a two-way (condition x sex) mixed model ANOVA with repeated measures and a nonparametric Friedman’s ANOVA, respectively. Both analyses were performed at a p\u3c.05 significance level. RESULTS: Analyses failed to detect any main condition or interaction effects for bench press 1RM, however, a statistically significant main sex effect was observed (p\u3c.001; ηp2=.597) favoring males relative to females (p\u3c.001; 114±22kg vs 68±16kg). Both peak power and velocity failed to reveal any significant main condition or sex effects, nor any interactions. Nonparametric assessments further revealed significant wrist wrap condition effects for both SS (p\u3c.001; Kendall’s W=.628) and SD (p\u3c.001; Kendall’s W=.935), whereby NW was statistically more comfortable (p\u3c.001) than either wrap condition, without any difference between DW and SW (p\u3e.05). CONCLUSION: Although wrist wraps did not significantly alter bench press-specific strength and power, participants nonetheless perceived wrist wraps as subjectively more stable irrespective of increased discomfort. ACKNOWLEDGEMENTS: The authors of this abstract would like to thank Peter Spence and SBD Apparel for generously donating the wrist wraps utilized in the present investigation