Investigation of ultrafast laser photonic material interactions: challenges for directly written glass photonics

Currently, direct-write waveguide fabrication is probably the most widely studied application of femtosecond laser micromachining in transparent dielectrics. Devices such as buried waveguides, power splitters, couplers, gratings and optical amplifiers have all been demonstrated. Waveguide properties depend critically on the sample material properties and writing laser characteristics. In this paper we discuss the challenges facing researchers using the femtosecond laser direct-write technique with specific emphasis being placed on the suitability of fused silica and phosphate glass as device hosts for different applications.Comment: 11 pages, 87 references, 11 figures. Article in revie

Feasibility study for reliable magnetic connection switch, phase I Final report

Feasibility of magnetic circuits for high reliability computer switche

Mission possible: diatoms can be used to infer past duckweed (lemnoid Araceae) dominance in ponds

Compared to larger lakes, ponds have rarely been the focus of palaeoecological studies. A common feature of ponds, especially those subject to eutrophication, is mass surface coverings of lemnoid Araceae (duckweed) which have severe implications for ecological processes in small waterbodies, in particular lowered oxygen content. To help understand the implications of duckweed dominance for the long-term ecology of ponds, and to determine the potential for palaeoecological studies in ponds more generally, we develop a new diatom-based Lemna-indicator metric. Recent studies of diatom host-plant relationships have shown significant associations between duckweed and the epiphytes Lemnicola hungarica and Sellaphora saugerresii (formally known as Sellaphora seminulum). To determine the potential of these species as palaeo-indicators of long-term duckweed dynamics in ponds, we investigated the diatom composition of surface sediment assemblages in sets of duckweed and non-duckweed-dominated ponds in Norfolk, eastern England. In addition, we undertook diatom analysis of two cores from a small farmland pond (Bodham Rail Pit) subject to a known duckweed dominance event (1999–2005). Both L. hungarica and S. saugerresii were significant predictors of past Lemna dominance in the surface sediments. Further, in the core study, both diatom species accurately and closely tracked the documented “on–off” duckweed cycle. Our study suggests huge potential for using ponds in palaeoecological studies and for diatom-based investigations of floating plant histories

The Energy Expenditure of Recreational Ballroom Dance

International Journal of Exercise Science 7(3) : 228-235, 2014. The popularity of recreational ballroom dancing has increased dramatically in recent years. Yet, relatively little information is known regarding the physiological demands of ballroom dancing. The purpose of this study was to determine the energy requirements for recreational ballroom dancing. 24 participants volunteered including 12 women (mean ± SD: 21 ± 3 yrs, 165.8 ± 7.4 cm, 56.8 ± 11.1 kg) and 12 men (23 ± 1 yr, 175.5 ± 8.4 cm, 78.1 ± 15.6 kg). Gas exchange was recorded using a portable metabolic system during a series of five ballroom dances: Waltz, Foxtrot, Swing, Cha-Cha, and Swing. Each song was four minutes in duration, separated by a two minute rest period, totaling 30 minutes of testing. The intensity of each dance in metabolic equivalents (METs) is: Waltz = 5.3 ± 1.3, Foxtrot = 5.3 ± 1.5, Cha-Cha = 6.4 ± 1.6 and Swing = 7.1 ± 1.6 and 6.9 ± 1.7. Mean energy cost for the 30 minutes of testing was 5.88 ±1.7 kilocalories (kcal•min-1), 6.12 ± 1.2 METs. Mean energy cost and months of recreational dance experience were not significantly related (R2 = 0.04, p = 0.35). Energy expenditure of the follow partner was significantly related to the energy expenditure of the lead partner (R2 = 0.52, p \u3c0.01). Finally, this study validates the intensity of recreational ballroom dance as matching the criteria established by the American College of Sports Medicine for improving cardiorespiratory fitness and reducing the risk of chronic diseases

Two-axis bend measurement with Bragg gratings in multicore optical fiber

We describe what is to our knowledge the first use of fiber Bragg gratings written into three separate cores of a multicore fiber for two-axis curvature measurement. The gratings act as independent, but isothermal, fiber strain gauges for which local curvature determines the difference in strain between cores, permitting temperature-independent bend measurement. (C) 2003 Optical Society of America

Effect of cyclosporine on hepatic cytosolic estrogen and androgen receptor levels before and after partial hepatectomy

Estrogen and androgen receptors within the liver have been reported to modulate the hepatic regenerative response to partial hepatectomy. Moreover, cyclosporine has several untoward effects that might occur as a consequence of alterations in sex hormone activity. To evaluate these questions the following experiments were performed. Estrogen and androgen receptors in cytosol were quantitated in livers of rats treated with cyclosporine or olive oil vehicle before and after partial hepatectomy or a sham operation. Ornithine decarboxylase activity and thymidine kinase activity were assessed as indices of hepatic regeneration. Preoperative levels of estrogen receptor activity in the hepatic cytosol were significantly greater in rats treated with cyclosporine as compared to vehicle treated controls (P<0.01). In contrast, preoperative levels of androgen receptor activity in the cyclosporine-treated and vehicle-treated animals were similar. Following partial hepatectomy, a reduction in the activity of both sex hormone receptors in the hepatic cytosol was observed and was compatible with results described previously in normal animals. Unexpectedly the preoperative levels of ornithine decarboxylase (P<0.01) and thymidine kinase activity (P<0.01) were significantly greater in the rats treated with cyclosporine as compared to the vehicle treated controls. As expected, ornithine decarboxylase activity (at 6 hr) and thymidine kinase activity (at 24 hr) rose and peaked in response to a partial hepatectomy but were significantly greater (P<0.05) in the rats treated with cyclosporine as compared to the vehicle. These results show that cyclosporine treatment causes an increase in the hepatic content of estrogen receptor activity that is associated with an enhanced potential for a regenerative response. These effects of cyclosporine treatment on the sex hormone receptor levels in liver may explain the mechanisms responsible for some of the untoward effects of treatment with this agent. © 1990 Plenum Publishing Corporation

Identifying sediment discontinuities and solving dating puzzles using monitoring and palaeolimnological records

Palaeolimnological studies should ideally be based upon continuous, undisturbed sediment sequences with reliable chronologies. However for some lake cores, these conditions are not met and palaeolimnologists are often faced with dating puzzles caused by sediment disturbances in the past. This study chooses Esthwaite Water from England to illustrate how to identify sedimentation discontinuities in lake cores and how chronologies can be established for imperfect cores by correlation of key sediment signatures in parallel core records and with long-term monitoring data (1945‒2003). Replicated short cores (ESTH1, ESTH7, and ESTH8) were collected and subjected to loss-on-ignition, radiometric dating (210Pb, 137Cs, and 14C), particle size, trace metal, and fossil diatom analysis. Both a slumping and a hiatus event were detected in ESTH7 based on comparisons made between the cores and the long-term diatom data. Ordination analysis suggested that the slumped material in ESTH7 originated from sediment deposited around 1805‒1880 AD. Further, it was inferred that the hiatus resulted in a loss of sediment deposited from 1870 to 1970 AD. Given the existence of three superior 14C dates in ESTH7, ESTH1 and ESTH7 were temporally correlated by multiple palaeolimnological proxies for age-depth model development. High variability in sedimentation rates was evident, but good agreement across the various palaeolimnological proxies indicated coherence in sediment processes within the coring area. Differences in sedimentation rates most likely resulted from the natural morphology of the lake basin. Our study suggests that caution is required in selecting suitable coring sites for palaeolimnological studies of small, relatively deep lakes and that proximity to steep slopes should be avoided wherever possible. Nevertheless, in some cases, comparisons between a range of contemporary and palaeolimnological records can be employed to diagnose sediment disturbances and establish a chronology

Locating and building knowledges outside of the academy : approaches to engaged teaching at the University of Sheffield

This article draws on three case studies, which illuminate a number of practical, ethical and intellectual issues that arise from engaged teaching activities within the curriculum. Projects from the disciplines of Architecture, English and Journalism Studies illustrate the possibilities offered by learning and teaching projects which emphasise public facing, co-produced knowledge as central components. It is argued that such approaches enable dynamic forms of learning to emerge, which work to expand the parameters of subject-specific knowledge while enabling the development of citizenship attributes and employability skills amongst students in ways that deepen, rather than dilute, intellectual rigour. The article locates these practical pedagogical reflections within theoretical frameworks offered by those working (largely in North America* on publicly engaged approaches to scholarship and seeks to draw connections with contemporary developments in learning and teaching in the UK. Keywords: civic university; engaged teaching; engaged scholarship; co-productio

Measuring Adolescent Ego-Identity Status: A Comparison of the Semistructured Interview and the Objective Measure of Ego-Identity Status

Erikson\u27s (1980) conceptualizations of the adolescent developmental task of identity development as operationalized by Marcia (1966) into four statuses (identity achieved, moratorium, foreclosure and diffusion) have been measured by both interviews and questionnaires. Research using Marcia\u27s (1966) Ego Identity Interview and studies incorporating the Adams and colleagues\u27 Extended Objective Measure of Ego Identity Status (EOM-EIS) questionnaire have been reported as having acceptable levels of reliability and validity. However direct status-to-status comparisons of the OM-EIS and the Marcia interview identity status classifications have shown only moderate agreement. This study re-examined the internal consistency and construct validity of the EOM-EIS and the Marcia interview and contrast several strategies of assessing concurrent validity. A convenience sample of 61 16-year-old adolescents were utilized to address these issues. The major findings included: (a) both instrumentations showed acceptable to sound estimates of internal reliability, internal validity and construct validity, (b) congruence between classification schemes is moderate, (c) most of the convergence between the EOM-EIS and the semistructured interview exists in ideological exploration, and (d) the EOM-EIS displayed superior estimates of predictive validity. The primary conclusion of this study is, while the EOM-EIS displayed the best overall match with Eriksonian theory, considering the long-term acceptance and usage of the semistructured interview strategy and the limitations of this particular study, that the EOM-EIS and the semistructured interview are approximately equally capable (or incapable) of assessing the underlying psychological processes involved in ego-identity formation. Also some considerations for ego-identity instrumentation are offered and a cubic model of ego-identity classification is proposed