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Purpose: The purpose was to determine the effect of a single-dose prophylactic ibuprofen use before a 164-km road cycling event in high ambient temperature on the circulating cytokine and leukocyte responses. Methods: Twenty-three men (53 ± 8 y, 172.0 ± 22.0 cm, 85.1 ± 12.8 kg, 19.6 ± 4.4% body fat) completed a 164-km self-paced recreational road cycling event in a hot, humid, sunny environment (WBGT = 29.0 ± 2.9°C) after consuming 600 mg of ibuprofen (n = 13) or a placebo (n = 10). Blood samples were obtained one to two hours before (PRE) and immediately after (POST) the event, and analyzed for concentrations of circulating cytokines interleukins (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, GM-CSF, IFN-γ, and TNF-α and leukocytes (total leukocytes, granulocytes, monocytes, and lymphocytes). Results: Event completion time was 400.2 ± 74.8 min. Concentrations of all cytokines (except IL-1β, IL-2, IL-5, IL-12, GM-CSF, and IFN-γ) and of all leukocyte subsets increased from PRE to POST. Ibuprofen ingestion attenuated the increase in IL-10 (86% increase with Ibuprofen; 270% increase with placebo). Conclusions: Consuming 600 mg of Ibuprofen prior to a 164-km road cycling event in a hot-humid environment attenuates exercise-induced increases in the concentration of the anti-inflammatory cytokine IL-10, but does not alter the effect of the exercise event on concentrations of other circulating cytokines or leukocyte subset concentrations. [ABSTRACT FROM AUTHOR]

Roman‐period mummy portraits are considered to be ancient antecedents of modern portraiture. However, the techniques and materials used in their manufacture are not thoroughly understood. Analytical study of the pigments as well as the binding materials helps to address questions on what aspects of the painting practices originate from Pharaonic and/or Graeco‐Roman traditions, and can aid in determining the provenance of the raw materials from potential locations across the ancient Mediterranean and European worlds. Here, one of the largest assemblages of mummy portraits to remain intact since their excavation from the site of Tebtunis in Egypt was examined using multiple analytical techniques to address how they were made. The archaeological evidence suggests that these portraits were products of a single workshop and, correspondingly, they are found to be made using similar techniques and materials: wax‐based and lead white–rich paint combined with a variety of iron‐based pigments (including hematite, goethite and jarosite), as well as Egyptian blue, minium, indigo and madder lake to create subtle variations and tones. [ABSTRACT FROM AUTHOR]

Background/objectives: Void frequency (VF) is significantly correlated to hydration status, but it is unknown whether VF is reliable when an individual is repeatedly euhydrated (EU) or hypohydrated (HY). The purpose of this study was to test the reliability of VF when individuals were EU or HY on multiple occasions.Subjects/methods: Fourteen males (age 22±2 years, mass 79.1±12.8 kg) completed three EU trials achieved with 24-h ad libitum fluid intake, and 14 males (age 22±2 years, mass 78.6±10.4 kg) completed three HY trials achieved with 24-h fluid restriction. Twenty-four hour urine was collected and analyzed for specific gravity (USG) and VF. Subjects voided at a 'normal urgency' (rated a '2' on a 0-4 perceptual scale) throughout each 24-h period.Results: Twenty-four hour USG was greater and VF was lower when HY (1.026±0.003 and 5±2, respectively) versus EU (1.014±0.003 and 7±2; both P<0.05). Intra-class correlations for VF between the three trials at each hydration status were deemed acceptable (0.863 and 0.849 for EU and HY, respectively). Within-subject coefficients of variation for VF were 15±9 and 21±14% for the EU and HY trials.Conclusions: VF is a reliable index of 24-h hydration status when healthy young males are EU or HY and voiding at a consistent 'urgency'. [ABSTRACT FROM AUTHOR]

In non-smokers, passive heat stress increases shear stress and vasodilation, decreasing arterial stiffness. Smokers, who reportedly have arterial dysfunction, may have similar improvements in arterial stiffness with passive heat stress. Therefore, we examined the effects of an acute bout of whole-body passive heat stress on arterial stiffness in smokers vs. non-smokers. Thirteen smokers (8.8 ± 5.5 [median = 6] cigarettes per day for >4 years) and 13 non-smokers matched for age, mass, height, and exercise habits (27 ± 8 years; 78.8 ± 15.4 kg; 177.6 ± 6.7 cm) were passively heated to 1.5 °C core temperature ( T) increase. At baseline and each 0.5 °C T increase, peripheral (pPWV) and central pulse wave velocity (cPWV) were measured via Doppler ultrasound. No differences existed between smokers and non-smokers for any variables (all p > 0.05), except cPWV slightly increased from baseline (526.7 ± 81.7 cm · s) to 1.5 °C Δ T (579.7 ± 69.8 cm · s; p < 0.005), suggesting heat stress acutely increased central arterial stiffness. pPWV did not change with heating (grand mean: baseline = 691.9 ± 92.9 cm · s; 1.5 °C Δ T = 691.9 ± 79.5 cm · s; p > 0.05). Changes in cPWV and pPWV during heating correlated ( p < 0.05) with baseline PWV in smokers (cPWV: r = −0.59; pPWV: r = −0.62) and non-smokers (cPWV: r = −0.45; pPWV: r = −0.77). Independent of smoking status, baseline stiffness appears to mediate the magnitude of heating-induced changes in arterial stiffness. [ABSTRACT FROM AUTHOR]

Background/Objectives:Few user-friendly hydration assessment techniques exist for the general population to use on a daily basis. The present study evaluated void number over 24 h as a potential hydration assessment tool.Subjects/Methods:Male and female subjects collected urine for 24 h while adequately hydrated (n=44; 22±4 years, 168±16 cm, 73±15 kg) or fluid restricted (n=43; 22±3 years, 175±10 cm, 81±24 kg). As a control, participants were asked to void when feeling the 'first urge to void' on a commonly used urge scale and noted the volume of each void. For each sample, 24-h urine volume, osmolality (UOSM), specific gravity (USG) and color were measured in the laboratory.Results:As designed, the level of urge upon voiding was consistent throughout the study (2±0; 'first urge to void'). Samples were classified by USG as either euhydrated (USG<1.020) or hypohydrated (USG⩾1.020). Grouping by UOSM did not change results. Euhydrated versus hypohydrated individuals had greater 24-h urine volume (1933±864 versus 967±306 ml, respectively) and lower urine color (2±1 versus 5±1), USG (1.012±0.004 versus 1.025±0.004) and UOSM (457±180 versus 874±175 mOsm/kg H2O; all P<0.001). Euhydrated individuals voided more than hypohydrated individuals over the 24-h period (5±2 versus 3±1 voids; P<0.001). Additionally, void number inversely correlated with hydration status as identified by USG (r=−0.50; P<0.05) and UOSM (r=−0.56; P<0.05).Conclusions:In conclusion, over 24 h, individuals with a higher void number were euhydrated (that is, had less concentrated hydration biomarkers) than those with a lower void number. Based on these data, void number might be utilized as a simple and feasible hydration assessment for the general public, as it utilizes no equipment or technical expertise. [ABSTRACT FROM AUTHOR]

New Findings What is the central question of this study? Simulated haemorrhage increases ventilation prior to presyncope, possibly increasing venous return through the respiratory pump. Heat stress alone also increases ventilation. It is unknown whether this increased ventilation would be greater with combined heat stress and simulated haemorrhage., What is the main finding and its importance? Our data suggest that the increased ventilation during simulated haemorrhage induced via lower body negative pressure is not altered in heat-stressed humans. These findings have implications for individuals who are often heat stressed and at a higher risk of haemorrhagic injury. During a hypotensive challenge whilst heat stressed, these individuals are unlikely to realize benefits of a heightened respiratory pump relative to when they are normothermic., Simulated haemorrhage, e.g. lower body negative pressure (LBNP), reduces central blood volume and mean arterial pressure, while ventilation increases. Passive whole-body heat stress likewise increases ventilation. The objective of this project was to test the hypothesis that ventilatory responses to reductions in central blood volume and arterial pressure during simulated haemorrhage are enhanced when individuals are heat stressed rather than normothermic. Eight healthy men (34 ± 9 years old, 176 ± 6 cm tall and 80.2 ± 4.2 kg body weight) underwent a simulated haemorrhagic challenge via LBNP until presyncope on two separate occasions, namely normothermic control and whole-body heat-stress trials. Baseline ventilation and core and mean skin temperatures were not different between trials (all P > 0.05). Prior to LBNP, heat stress increased core (from 36.8 ± 0.2 to 38.2 ± 0.2°C, P < 0.05) and mean skin temperatures (from 33.9 ± 0.5 to 38.1 ± 0.6°C, P < 0.05), as well as minute ventilation (from 8.01 ± 2.63 to 13.68 ± 6.68 l min-1, P < 0.01). At presyncope, mean arterial pressure and middle cerebral artery blood velocity decreased in both trials ( P < 0.05). At presyncope, ventilation increased to 23.22 ± 6.78 ( P < 0.01) and 25.88 ± 10.16 l min-1 ( P < 0.01) in the normothermic and hyperthermic trials, respectively; however, neither the increase in ventilation from the pre-LBNP period nor the absolute ventilation was different between normothermic and hyperthermic trials ( P > 0.05). These data suggest that the increase in ventilation during simulated haemorrhage induced via LBNP is not altered in heat-stressed humans. [ABSTRACT FROM AUTHOR]

In this study, we have evaluated the applicability of Nd isotopic analysis for the provenancing of Roman glass and we present a database of Nd isotopic compositions of possible sand raw materials from the western Mediterranean, as a means of comparison for the growing number of isotopic studies on ancient glass. The 143Nd/144Nd isotope ratio of sands is a good indicator for their geological (and sometimes geographical) provenance. The use of the isotopic signature of Nd as a proxy for the source of silica in glass is, however, not always straightforward because of the possible overlap of signatures from different suppliers. [ABSTRACT FROM AUTHOR]

The provenancing of Roman natron glass is one of the most challenging problems in the field of archaeometry. Although the use of Sr and Nd isotope ratios and trace element signatures as an indication of provenance has proven promising, there are still many unknowns. In this study, the influence of the different raw materials on the final Sr isotopic composition of Roman natron glass is examined. It is shown that the 87Sr/86Sr ratio in natron glass is significantly influenced by the silicate fraction of the sand used and does not always provide a clear indication of the lime source used. [ABSTRACT FROM AUTHOR]

In this study analysis of major elements and Sr--Nd isotopes is performed on 33 colourless glass fragments from two Ro- man shipwrecks discovered in the Northern Mediterranean Sea, the Iulia Felix (irst half of the third century AD) and the Ouest-Embiez (end of the second--beginning of the third century AD). Two compositional groups are deined based upon the major elements analysis, suggesting the use of diferent raw materials, and possibly the production of the glass samples in two separate factories. Sr--Nd isotopes, promising indicators for provenancing geological resources used as raw materials 87 86 in glass manufacturing, conirm the compositional groups. The Sr/ Sr signature is very close to the modern sea water signature (0·7092) for all samples, likely due to the use of shell as glass raw material. The Nd signature further subdivides the compositional groups, suggesting the use of three diferent sand raw materials for the production of glass. [ABSTRACT FROM AUTHOR]

The effects of exercise-induced dehydration and fluid ingestion on men's cognitive performance were assessed. Eleven young men attended separate sessions in which each individual cycled in a controlled environment at 60% of V̇2max for periods of 15, 60, or 120 mm without fluid replacement or 120 mm with fluid replacement. Immediately following the assigned submaximal exercise period, the participant completed a graded exercise test to voluntary exhaustion. An executive processing test and a short-term memory test were performed prior to and immediately following exercise. Choice-response times during the executive processing test decreased following exercise, regardless of the level of dehydration. Choice-response errors increased following exercise, but only on trials requiring set shifting. Short-term memory performance improved following exercise, regardless of the level of dehydration. Changes in cognitive performance following exercise are hypothesized to be related to metabolic arousal following strenuous physical activity. [ABSTRACT FROM AUTHOR]