Muscle damage response in female collegiate athletes following repeated sprint activity

Exercise induced muscle damage (EIMD) is a well-investigated area, however there is a paucity of data surrounding the damage response in females. The aim of this study was to examine the damage responses from a sport-specific bout of repeated sprints in female athletes. Eleven well-trained females (mean ± SD; age 22 ± 3 y, height 166.6 ± 5.7 cm, mass 62.7 ± 4.5 kg) in the luteal phase of the menstrual cycle completed a repeated sprint protocol designed to induce EIMD (15 × 30 m sprints). Creatine kinase (CK), countermovement jump height (CMJ), knee extensor maximum voluntary contraction force (MVIC), muscle soreness (DOMS), 30 m sprint time and limb girth were recorded pre, post, 24 h, 48 h and 72 h post exercise. CK was elevated at 24, 48 and 72 h (p < 0.05), peaking at 24 h (+418%) and returning towards baseline at 72 h. CMJ height was reduced immediately post, 24 and 48 h (p < 0.05). Sprint performance was also negatively affected immediately post, 24 h, 48 h and 72 h post exercise. Muscle soreness peaked at 48 h (p<0.01) and remained significantly elevated at 72 h post exercise (p<0.01). Limb girth and MVIC did not alter over time. The current study provides new information on the EIMD response in trained females following a sport specific bout of repeated sprints. Importantly, this damage response has the potential to negatively affect performance for several days post-exercise

Methodological developments in the luminescence dating of brick from English late medieval and post medieval buildings

Fired clay brick samples, obtained from a group of seven high-status late-medieval and post-medieval buildings in England ranging in age from c. ad 1390 to 1740, were dated by the luminescence method using an optically stimulated luminescence (OSL) technique. The results obtained indicate that, when applied to quartz extracted from brick, the technique is capable of producing dates that are in consistently good agreement with independent dating evidence for the buildings. For six samples taken from a group of four dating 'control' buildings the mean difference between the central values of luminescence and assigned ages was 5 ± 10 years (SD, n = 6). The methodology used is appropriate for application to other standing buildings in other temporal and geographic regions, and may be used with confidence where conventional dating methods are less certain. The study also examines the luminescence characteristics of quartz and the characteristics of the lithogenic radionuclides in brick samples and identifies various aspects related to the assessment of experimental uncertainty in testing the reliability of the method

Development of single grain OSL dating of ceramic materials: Spatially resolved measurement of absorbed dose

The feasibility of using an OSL scanning technique to determine the cumulative absorbed dose for single inclusions in sliced brick samples is explored in this paper. The OSL scanner was configured to provide optical stimulation using laser sources with either blue/green or near-IR wavelengths. A regenerative OSL procedure was successfully applied to determine the palaeodose for single grains of quartz in the surface of the ceramic slices ranging in diameter from 60 to . The results obtained compare well with calculated values of palaeodose obtained by scaling the measured values of palaeodose obtained using a single aliquot regenerative procedure with disaggregated quartz inclusions extracted from the same brick and prepared using the conventional inclusion technique

The use of calcium silicate bricks for retrospective dosimetry

The suitability of calcium silicate bricks (CSBs) for the retrospective measurement of gamma dose using luminescence techniques has been investigated. Bricks of this type are distinguished from fired clay bricks by containing negligible clay and requiring comparatively low temperature treatment during manufacture. They have been used widely in the construction of buildings in the Former Soviet Union since the 1970s but hitherto have not been used for retrospective dosimetry measurements. A procedure based on the use of the 210°C thermoluminescence (TL) peak of quartz was tested with granular quartz extracted from three types of CSB, one of which had been taken from a settlement downwind of Chernobyl. The degree to which the residual geological TL signal within the temperature range of the 210°C TL peak had been reduced during manufacture varied with brick type; the levels of residual TL corresponded, in the samples tested, to absorbed doses in the range (<5 mGy–100 mGy). The TL sensitivity of the quartz was generally sufficient to measure absorbed doses of 20 mGy and above. An estimate of the cumulative fallout dose obtained with the CSB from the contaminated settlement was in good agreement with that obtained in a previous study based on measurements with a fired clay brick from the same building

Two-photon excitation and luminescence of a CaWO4 scintillator

Luminescence of a CaWO4 scintillator was studied in the temperature range 77–500 K using intense laser excitation in the 450–600 nm spectral region. Characteristics of the observed blue emission are similar to those of the intrinsic luminescence of calcium tungstate. The emission is concluded to be caused by cascade excitation of CaWO4 that results in a two-photon excited (TPE) luminescence. The features of TPE luminescence of CaWO4 are analysed in comparison to those obtained with UV and X-ray excitation

Uses and recycling of brick in medieval and Tudor English buildings: insights from the application of luminescence dating and new avenues for further research.

Luminescence dating has been applied to ceramic bricks sampled from a selection of English medieval ecclesiastical and secular buildings in Essex, Kent and Lincolnshire, ranging in age from the fourth to the late sixteenth centuries. The results obtained for the Anglo-Saxon churches, which included Brixworth, confirmed the reuse of Roman brick in all cases. The dates for the earliest medieval brick type indicate that brick making was reintroduced during the eleventh century, a century earlier than previously accepted, and dates for bricks from the same secular Tudor building indicate that the practice of recycling of building materials during the late medieval period was also applied to brick

One- and two-photon excited luminescence and band-gap assignment in CaWO4

Luminescence properties of CaWO4 have been investigated using complementary one- and two-photon excitation techniques. Analysis of the thermal changes in the luminescence spectra indicates that the observed high-energy shift of the CaWO4 emission maximum is mainly caused by a change of position of the intrinsic blue band. The thermal broadening and shift of this band can be interpreted satisfactorily in terms of a model of the luminescence center interacting with the vibrating crystalline environment. The characteristic parameters of the phonon system obtained from the experiment agree with those from earlier independent studies. Intense laser stimulation of CaWO4 in the spectral region &lt;505 nm (&gt;2.45 eV) results in emission with spectral and kinetics features that are characteristic of the radiative decay of a WO42- oxyanion complex in this crystal. The kinetics of luminescence decay under two-photon excitation changes with increasing excitation density due to exchange interaction of the elementary excitations. From a comparative analysis of the optical properties of CaWO 4 obtained in the course of two-photon and one-photon spectroscopic studies (absorption, reflection, one- and two-photon excitation spectra) it is concluded that the energy gap of the crystal is 5.2 ± 0.3 eV