Reactive oxygen species may contribute to exercise-induced skeletal muscle damage, and antioxidants may protect against such damage. This study examined the effectiveness of prophylactic supplementation with vitamins C and E on symptoms of muscle damage in a single blind, two-group study design. Twelve male volunteers were randomly assigned to either treatment or control groups. The treatment group received 500 mg of vitamin C and 1,200 IU of alpha-tocopherol daily and the control group received glucose placebo for 37 days. After 30 days of treatment, volunteers performed 300 maximal eccentric contractions of the knee extensor muscles of one leg. Maximal voluntary isometric contraction force and electrically evoked force at a frequency of 20 Hz and 50 Hz were recorded before and after exercise, and on days 1, 2 and 7 after exercise. Muscle soreness questionnaires were completed and muscle girth recorded at the same time points. Eccentric contractile torque and work during the bout declined significantly in both groups ( P<0.001), but this decline was smaller in the vitamin-supplemented group ( P<0.05). Maximal voluntary isometric contraction force and 20:50 Hz force ratio declined significantly after exercise in both groups ( P<0.01), but the decline was smaller in the treatment group on days 1 and 2 post-exercise ( P<0.05). Both groups experienced similar significant muscle soreness and swelling after exercise. These data suggest that prior supplementation with dietary antioxidants ameliorates muscle functional decrements subsequent to eccentric muscle contraction.

The intense tropical fruit aroma of Sauvignon blanc wines has been associated with the varietal thiols 3-mercaptohexanol (3MH), derived from odorless precursors in the grape, and 3-mercaptohexyl acetate (3MHA), arising from 3MH during fermentation. Grapes and juice were sourced from five locations in Marlborough, New Zealand, taking hand-picked grapes and samples at four stages during the mechanical harvesting process and pressing, which were then fermented in replicated 750 mL bottles. With each set of juices, the highest concentrations of Cys-3MH and Glut-3MH were found in the juices pressed to 1 bar, but these juices produced wines with lower 3MH and 3MHA concentrations. With three of the juices, there was an increase in varietal thiol content for wines made from juices that had been machine harvested compared to the hand-picked samples, which matched earlier findings of lower 3MH and 3MHA levels in wines made from hand-picked grapes. Juices that were more oxidized, and which showed a higher absorbance at 420 nm, were found to produce wines with lower 3MH and 3MHA concentrations.

BackgroundDietary intervention trials rely on self-reported measures of intake for assessment of energy and macronutrient composition. Dietary fat intake is of particular interest due to strong associations with pathophysiology. In epidemiological trials phospholipid fatty acid composition may reflect composition of habitual diet, although strong correlations have been identified only for essential polyunsaturated fatty acids (PUFAs). Preliminary evidence shows that saturated fatty acids (SFA) C15:0 and C17:0 may be acceptable biomarkers. This study measured changes in erythrocyte membrane fatty acids during a period of strictly controlled fat feeding to investigate their use as a short-term marker of compliance, particularly for intake of SFAs.ResultsThis was a randomised cross-over trial in which diet was provided and strictly controlled. 20 healthy, male subjects were given a 40 energy % (en%) fat diet, high in saturated (high-SFA, 20 en%) or unsaturated (high-USFA, 24 en%) fatty acids for 2 periods of 3 weeks. Subjects were residential during intervention with all food and beverages provided. Dietary composition was verified by direct chemical analysis. Blood samples were collected on days 1,7,14, 21 and analysed for red blood cell (RBC) membrane fatty acid composition. Pearson correlation showed RBC fatty acid composition to mimic dietary composition by 3 weeks, but the relationships were weak. Of the SFAs only RBC C16:0 decreased in response to decreased dietary content on high-USFA treatment (ANOVA, diet, P < 0.05). Of the USFAs, higher levels of C18:1 MUFA, C20:4 and C22:6 long chain PUFA on high-USFA diet lead to higher C18:1, C20:4 and C22:6 within RBCs (ANOVA, time*diet, P < 0.05). Pearson's correlation was significant between dietary and RBC fatty acids during the 21d dietary manipulation for C18:1, and C20:5, C22:6 only (P < 0.05).ConclusionRBC membrane fatty acids cannot reliably be used as an independent measure of compliance for dietary SFA intake in short-term studies. The MUFA oleic acid and PUFAs EPA and DHA may be more useful as markers of compliance during short term intervention trials.

The construction of a simple absorption monitor for capillary electrophoresis, based on a bright blue-green light emitting diode as radiation source, is described. Fibre optic coupling between light source, capillary and photodiode detectors was employed. It was found that, owing to the use of a high intensity light emitting diode, no optical focusing elements were required. The performance of the device was found to be comparable to that of a commercial detector, and the versatility is demonstrated with methods for the determination of transition metal ions by complexation with 4-(2-pyridylazo)resorcinol and the indirect detection of other inorganic cations and anions using organic dyes.

Surface wipe sampling for methamphetamine is a standard protocol in many jurisdictions for sampling at suspected or known former clandestine methamphetamine laboratories, but this method relies on samples being taken from representatively contaminated surfaces. We have investigated whether a rapid sampling method for airborne methamphetamine can be used to supplement surface sampling. A dynamic solid phase microextraction (SPME) field sampler was constructed and tested in the field and in the laboratory. This device enabled large volumes of air to be passed over SPME fibres exposed during the comparatively short time (<2 h) that a testing company might be present at a former clandestine laboratory. The collected samples were then analyzed by gas chromatography-mass spectrometry.Airborne methamphetamine was detected with this method at former clandestine methamphetamine laboratory sites where surface wipe sampling showed surface methamphetamine concentrations greater than 40 mg/100 cm 2 . † Electronic supplementary information available: GC-MS chromatogram from an SPME bre exposed during cleaning of a clandestine laboratory. See

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A carbon composite strain sensing system using an embedded array of polymide-coated fiber Bragg grating sensors, which are interrogated by a tunable laser, is described. The system is controlled from a personal computer using a customized program. The system was tested using a composite panel consisting of 28 plies of carbon fiber. Consistent strain measurements were achieved using a laser scan resolution of 0.02 nm, which corresponds to a strain resolution of approximately 15 . Simulations of the panel were carried out using the Marc/Mentat finite element program for advanced engineering analysis. The experimental results compared well to those obtained from the simulations.