Identification of cellulose nitrate X-ray film for the purpose of conservation: Organic elemental analysis     

Konstantina Konstantinidou  Emma Humphreys-Williams  Mark Kearney 《文物保护研究》2017,62(1):24-32

Cellulose nitrate was widely used as a film base for photography, cinematography, and radiography in the first half of the twentieth century. Its stability is inherently poor and subject to environmental storage conditions. The risk of fire and the cross-infection effect on the cellulose acetate film stored at the same location necessitate that cellulose nitrate is identified within collections and stored separately. Not only medical archives, but also museums using radiography in their research may hold a sizeable amount of historical X-ray films. The Natural History Museum, London has been using film for X-radiography since before World War II. This suggests that some of the X-ray materials in its collections have a cellulose nitrate rather than ‘safety’ (cellulose acetate or polyester) film base. X-ray sheets rarely contain information related to their composition so science-based identification methods must be used. We propose the determination of nitrogen content in the film by organic elemental analysis (OEA) as a reliable method for the identification of films (X-ray, photographic, or cinematographic) with a cellulose nitrate base. Though it is a destructive method, the sample size required is small (<1?mg). This method does not require any sample preparation apart from weighing the samples and wrapping them in tin foil. OEA proved to be more accurate than the ‘float’ test in trichloroethylene and quicker and more straightforward to perform than infrared spectroscopy.  相似文献   

Physiological load associated with a Zumba® fitness workout: a comparison pilot study between classes and a DVD     

Anne Delextrat  Emma Neupert 《Journal of sports sciences》2016,34(1):47-55

The objectives were to compare the metabolic load elicited by Zumba^® classes and DVD workouts and link the physiological responses to participants’ psychological characteristics. Fifteen women (25.4 ± 4.3 years old; 164.9 ± 5.1 cm; 56.9 ± 5.8 kg; 23.9 ± 4.9% body fat) performed three Zumba^® classes and three Zumba^® DVD workouts using a repeated measure design. Energy expenditure was assessed by extrapolating oxygen cost from heart rate (HR) using regressions from a preliminary incremental running test. Differences between Zumba^® classes and Zumba^® DVD workouts were assessed by Student’s T tests and repeated measures analysis of variance and correlations between physiological and psychological variables by the Pearson’s coefficient. Results showed that Zumba^® classes allowed greater energy expenditure compared to Zumba^® DVD workouts (6.8 ± 0.9 vs 5.6 ± 0.9 kcal · min^?1, 95% confidence interval (CI) limits: 0.3–2.1, P = 0.016), with significant differences in the time spent with a HR above 85% of HR reserve (14.7 vs 1.7%, 95% CI: 5.6–20.4, P = 0.021). Furthermore, women with a greater autonomy score showed a smaller difference between DVD and class (r = 0.511, P = 0.048), while greater differences were shown in women with greater interpersonal skills (r = ?0.563, P = 0.028). The results suggest that while both types of workouts are suitable to maintain fitness Zumba^® classes allow greater energy expenditure.  相似文献   

Effects of increasing and decreasing physiological arousal on anticipation timing performance during competition and practice     

Michael J. Duncan  Mike Smith  Elizabeth Bryant  Emma Eyre  Kathryn Cook  Joanne Hankey 《European Journal of Sport Science》2016,16(1):27-35

The aim of this study was to investigate if the effects of changes in physiological arousal on timing performance can be accurately predicted by the catastrophe model. Eighteen young adults (8 males, 10 females) volunteered to participate in the study following ethical approval. After familiarisation, coincidence anticipation was measured using the Bassin Anticipation Timer under four incremental exercise conditions: Increasing exercise intensity and low cognitive anxiety, increasing exercise intensity and high cognitive anxiety, decreasing exercise intensity and low cognitive anxiety and decreasing exercise intensity and high cognitive anxiety. Incremental exercise was performed on a treadmill at intensities of 30%, 50%, 70% and 90% heart rate reserve (HRR) respectively. Ratings of cognitive anxiety were taken at each intensity using the Mental Readiness Form 3 (MRF3) followed by performance of coincidence anticipation trials at speeds of 3 and 8 mph. Results indicated significant condition × intensity interactions for absolute error (AE; p = .0001) and MRF cognitive anxiety intensity scores (p = .05). Post hoc analysis indicated that there were no statistically significant differences in AE across exercise intensities in low–cognitive anxiety conditions. In high–cognitive anxiety conditions, timing performance AE was significantly poorer and cognitive anxiety higher at 90% HRR, compared to the other exercise intensities. There was no difference in timing responses at 90% HRR during competitive trials, irrespective of whether exercise intensity was increasing or decreasing. This study suggests that anticipation timing performance is negatively affected when physiological arousal and cognitive anxiety are high.  相似文献   

Evaluating a Multidimensional Reading Comprehension Program and Reconsidering the Lowly Reputation of Tests of Near‐Transfer          下载免费PDF全文

Douglas Fuchs  Emma Hendricks  Meagan E. Walsh  Lynn S. Fuchs  Jennifer K. Gilbert  Wen Zhang Tracy  Samuel Patton III  Nicole Davis‐Perkins  Wooliya Kim  Amy M. Elleman  Peng Peng 《Learning disabilities research & practice》2018,33(1):11-23

We conducted a 14‐week experimental study of 2 versions of a relatively comprehensive RC intervention that involved 50 classroom teachers, 15 tutors, and 116 children drawn in equal proportions from grades 3 and 5 in 13 schools in a large urban school district. Students were randomly assigned in equal numbers to the two tutoring conditions and a control group. Results indicated that students in the two tutored groups tended to perform comparably on all tests and to outperform controls (more so in grade 5 than grade 3) on near‐transfer but not far‐transfer measures of RC. This differential pattern of program effects for near‐ versus far‐transfer measures raises questions about how tests of near‐transfer and far‐transfer are conventionally understood.  相似文献   

Genetics and molecular biology of muscle adaptation     

Emma Clapp 《Journal of sports sciences》2013,31(14)

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The value of circulars in supervising the teaching of reading     

Emma Young Case 《Peabody Journal of Education》2013,88(4):220-222

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Developing tests of impaired coordination for Paralympic classification: normative values and test–retest reliability     

Mark J. Connick  Emma Beckman  Rebecca Deuble  Sean M. Tweedy 《Sports Engineering》2016,19(3):147-154

Current methods of assessing coordination in Paralympic classification are non-instrumented and are based on ordinal scales of measurement and therefore impede the development of evidence-based methods of classification. This paper describes an instrumented battery of tests that measure impaired coordination in a way that will permit evidence-based classification. Test–retest reliability and normative values for each of the tests are reported. Twenty participants visited the laboratory on two occasions, each time completing 11 tests: three running-specific, lower-limb reciprocal tapping tests (yielding five outcome measures); four throwing-specific, upper-limb discrete tapping tests (yielding four outcome measures); and four wheelchair-specific, upper-limb reciprocal tapping tests yielding seven outcome measures. Reliability was evaluated using Intra-class Correlation Coefficients (ICCs), Standard Error of Measurement, Limits of Agreement and Paired t-tests. ICCs for fourteen of the 16 outcome measures were excellent (ICC ≥ 0.80), although systematic bias was evident in two of these—a unilateral, running-specific lower-limb tests on the non-dominant side, and a unilateral wheelchair-specific upper limb test on the dominant side. ICCs for two tests—a bilateral wheelchair-specific upper limb test (0.74), and a unilateral wheelchair-specific upper limb test on the non-dominant side (0.54)—were good and fair respectively. Results indicate that 12 of the measures evaluated have measurement properties that will facilitate the development of evidence-based methods of Paralympic classification in athletics. Positional adjustment and increased familiarization may improve reliability in the other four. Studies evaluating reliability of this test battery in people with coordination impairments are warranted.  相似文献   

Played in London: Charting the Heritage of a City at Play     

Emma Lile 《国际体育史杂志》2016,33(6-7):757-759

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The theory of everything?     

Emma Tobin 《Metascience》2012,21(1):65-69

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What Are Little Learners Made of? Sugar and Spice and All Things Nice,and Leptin and TNFα and Melatonin     

Emma K. Adam 《Mind, Brain, and Education》2013,7(4):243-245

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