Effects of Virtual Reality-Based Aerobic Exercise on Perceptions of Pain and Fatigue in Individuals with Spinal Cord Injury.

Virtual reality (VR) has become an effective alternative to promote exercise. However, limited studies have investigated the effect of VR on pain and fatigue in individuals with spinal cord injury (SCI). Objective: The purpose of this study was to investigate the effects of using VR during exercise on pain and fatigue in individuals with SCI. This study employed a concurrent nested mixed-methods design. Materials and Methods: Eleven individuals with SCI completed a 6-minute exercise test using arm ergometry with and without VR. Pain and fatigue questionnaire data were collected using Pain Self Efficacy Questionnaire, the Fatigue Severity Scale, and the Fatigue Assessment Scale. Qualitative data were collected after the VR session. Results: Participants experienced less pain and fatigue during VR exercise than during non-VR exercise. Qualitative data were consistent with the questionnaire results. Conclusion: Clinicians should consider the use of VR in reducing pain and fatigue.

Aquatic treadmill walking at three depths of water in people with traumatic brain injury.

OBJECTIVE: The purpose of this study was to analyse kinematic and spatiotemporal gait characteristics of aquatic treadmill walking among three different depths of water in individuals with traumatic brain injury. METHODS: A total of 13 individuals with traumatic brain injury participated in the study and completed walking trials at three different depths as follows: waist, chest, and neck level, which was adjusted by a movable floor pool. A self-selected comfortable walking speed at the waist level was used as a matched speed for all walking trials. Participants completed three aquatic treadmill walking trials under each of the three water depths. Each participant's gait was captured by a customized underwater motion analysis system and processed by a two-dimensional motion analysis software. RESULTS: The repeated measures analysis of variance showed significant differences in spatiotemporal and joint kinematic variables across three conditions: stance swing ratio (p = .023), peak hip flexion (p = .001), hip range of motion (p = .047), and peak ankle dorsiflexion (p = .000). Various water properties in conjunction with motor impairments might have contributed to alterations in gait kinematics. CONCLUSION: Our findings suggest that walking in neck-depth water may not be ideal for gait training as it appears to limit hip flexion and ankle dorsiflexion. It is recommended that waist to chest-depth water be used to provide an accommodating environment for aquatic gait rehabilitation.

Stable carbon and hydrogen isotope analysis of methyl tert-butyl ether and tert-amyl methyl ether by purge and trap-gas chromatography-isotope ratio mass spectrometry: method evaluation and application.

In order to monitor the behaviour of contaminants in the aqueous environment effective enrichment techniques often have to be employed due to their low concentrations. In this work a robust and sensitive purge and trap-gas chromatography-isotope ratio mass spectrometry method for carbon and hydrogen isotope analysis of fuel oxygenates in water is presented. The method evaluation included the determination of method detection limits, accuracy and reproducibility of deltaD and delta(13)C values. Lowest concentrations at which reliable delta(13)C values could be determined were 5 microg L(-1) and 28 microg L(-1) for TAME and MTBE, respectively. Stable deltaD values for MTBE and TAME could be achieved for concentrations as low as 25 and 50 microg L(-1). Good long-term reproducibility of delta(13)C and deltaD values was obtained for all target compounds. But deltaD values varying more than 5 per thousand were observed using different thermal conversion tubes. Thus, a correction of deltaD values in the analysis of groundwater samples was necessary to guarantee comparability of the results. The applicability of this method was shown by the analysis of groundwater samples from a gasoline contaminated site. By two dimensional isotope analysis two locations within this site were identified at which anaerobic and aerobic degradation of methyl tert-butyl ether occurred.

Flow injection analysis-isotope ratio mass spectrometry for bulk carbon stable isotope analysis of alcoholic beverages.

A new method for bulk carbon isotope ratio determination of water-soluble samples is presented that is based on flow injection analysis-isotope ratio mass spectrometry (FIA-IRMS) using an LC IsoLink interface. Advantages of the method are that (i) only very small amounts of sample are required (2-5 microL of the sample for up to 200 possible injections), (ii) it avoids complex sample preparation procedures such as needed for EA-IRMS analysis (only sample dilution and injection,) and (iii) high throughput due to short analysis times is possible (approximately 15 min for five replicates). The method was first tested and evaluated as a fast screening method with industrially produced ethanol samples, and additionally the applicability was tested by the measurement of 81 alcoholic beverages, for example, whiskey, brandy, vodka, tequila, and others. The minimal sample concentration required for precise and reproducible measurements was around 50 microL L(-1) ethanol/water (1.71 mM carbon). The limit of repeatability was determined to be r=0.49%. FIA-IRMS represents a fast screening method for beverage authenticity control. Due to this, samples can be prescreened as a decisive criterion for more detailed investigations by HPLC-IRMS or multielement GC-IRMS measurements for a verification of adulteration.

Determination of 13C/12C isotopic ratios of biogenic organometal(loid) compounds in complex matrixes.

Methylated metal(loid) compounds are formed in the environment by abiotic as well as enzymatically catalyzed transfer of a methyl group. Due to the increased mobility and toxicity in comparison to the inorganic precursors, the investigation of the formation process is of high relevance. Though the natural abundance carbon isotope ratio can give important insights toward their origin as well as the biochemical methyl transfer process, so far, these species have not been investigated by carbon isotope ratio mass spectrometry (IRMS). This is due to the analytical challenge to precisely determine the natural isotope distribution of trace amounts of metal(loid)-bound carbon in complex organic matrixes. To overcome this problem, we tested the concept of selective derivatization of nonvolatile organometal(loid)s by hydride generation (HG) followed by purge and trap (P-T) enrichment, heart-cut gas chromatography (hcGC), and subsequent analysis by GC/IRMS. Parameter optimization of HG/P-T/hcGC was conducted using online coupling to element-sensitive ICPMS (inductively coupled plasma mass spectrometry) detection. The purity of the HG/P-T/hcGC fraction was verified by GC/MS. For the model substance trimethylarsine oxide (TMAsO), an excellent agreement of the delta(13)C-value analyzed by HG/P-T/hcGC-GC/IRMS was achieved in comparison to the bulk delta(13)C-value, which shows that no significant isotope fractionation occurred during hydride generation and subsequent separation. The optimized method showed good reproducibility and a satisfying absolute detection limit of 4.5 microg TMAsO (1.2 microg(carbon)). This method was applied to the analysis of TMAsO in compost. The low delta(13)C value of this compound (-48.38 +/- 0.41 per thousand) indicates that biomethylation leads to significant carbon fractionation. HG/P-T/hcGC-GC/IRMS is a promising tool for investigation of the biomethylation process in the environment.