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Background: Two-point discrimination (TPD) is an assessment of tactile acuity. People with multiple sclerosis (MS) can have reduced foot sole tactile acuity, which has been linked to impaired balance. Objective: To quantify the test–retest reliability of TPD on the sole of the foot in people with MS. Approach: 41 participants (32 females), with mean (SD) age of 60 (9) years, and Expanded Disability Status Scale of <7.5, had their TPD measured at the head of the first metatarsal and the heel on two occasions, 2–14 d apart. Mean systematic change, within-subjects SD, limits of agreement (LOA), coefficient of variation and the intraclass correlation coefficient (ICC) were quantified as point estimates (95% CI). Main results: Systematic learning effects were evident. The within-subjects SD at the metatarsal and the heel was 6.7 mm (5.5–8.6) and 8.3 mm (6.7–10.8), and the LOAs were 18.6 mm (15.2–24.) and 23.7 mm (18.7–30.1), respectively. ICCs for metatarsal and heel was 0.87 (0.76–0.93) and 0.90 (0.80–0.95), respectively, but these were likely inflated by sample heterogeneity. Significance: In people with MS, TPD on the sole of the foot has an adequate test–retest reliability for research purposes, but there is substantial measurement variability for individual patients. [ABSTRACT FROM AUTHOR]

Summary: Worldwide prevalence of adult overweight and obesity is a growing public health issue. Adults with overweight/obesity often have chronic musculoskeletal pain. Using a mixed‐methods review, we aimed to quantify the effectiveness and explore the appropriateness of weight loss interventions for this population. Electronic databases were searched for studies published between 01/01/90 and 01/07/16. The review included 14 randomized controlled trials that reported weight and pain outcomes and three qualitative studies that explored perceptions of adults with co‐existing overweight/obesity and chronic musculoskeletal pain. The random‐effects pooled mean weight loss was 4.9 kg (95%CI:2.9,6.8) greater for intervention vs control. The pooled mean reduction in pain was 7.3/100 units (95%CI:4.1,10.5) greater for intervention vs control. Study heterogeneity was substantial for weight loss (I2 = 95%, tau = ±3.5 kg) and pain change (I2 = 67%, tau = ±4.1%). Meta‐regression slopes for the predictors of study quality, mean age and baseline mean weight on mean study weight reduction were shallow and not statistically significant (P > 0.05). The meta‐regression slope between mean pain reduction and mean weight lost was shallow, and not statistically significant, −0.09 kg per unit pain score change (95%CI:−0.21,0.40, P = 0.54). Meta‐synthesis of qualitative findings resulted in two synthesized findings; the importance of healthcare professionals understanding the effects of pain on ability to control weight and developing management/education programmes that address comorbidity. [ABSTRACT FROM AUTHOR]

Introduction This feasibility study aimed to (i) develop a clinical protocol using a long-term potentiation-like repetitive stimulation protocol for transcutaneous electrical nerve stimulation in patients with upper limb complex regional pain syndrome and (ii) develop a research protocol for a single-blind randomised controlled trial investigating the efficacy of transcutaneous electrical nerve stimulation for complex regional pain syndrome. Methods This small-scale single-blind feasibility randomised-controlled trial planned to randomise 30 patients with upper limb complex regional pain syndrome to either a variant of transcutaneous electrical nerve stimulation or placebo transcutaneous electrical nerve stimulation for three weeks. Stimulation comprised 20 pulses over 1 s with a non-stimulation interval of 5 s, a so-called repetitive electrical stimulation protocol following the timing of long-term potentiation. Pain, function and body image were measured at baseline, post-treatment and at three months follow-up. At three months, participants were invited to one-to-one interviews, which were analysed thematically. Results A transcutaneous electrical nerve stimulation protocol with electrodes applied proximal to the area of allodynia in the region of the upper arm was developed. Participant concordance with the protocol was high. Recruitment was below target (transcutaneous electrical nerve stimulation (n = 6), placebo (n = 2)). Mean (SD) pain intensity for the transcutaneous electrical nerve stimulation group on a 0 to 10 scale was 7.2 (2.4), 6.6 (2.8) and 7.8 (1.9), at baseline, post-treatment and at three-month follow-up, respectively. Qualitative data suggested that some patients found transcutaneous electrical nerve stimulation beneficial, easy to use and were still using it at three months. Conclusion Patients tolerated transcutaneous electrical nerve stimulation well, and important methodological information to facilitate the design of a large-scale trial was obtained (ISRCTN48768534). [ABSTRACT FROM AUTHOR]

Coordination chemistry underlies the structure/function of biological metal complexes. Contextualising this chemical information within an organism’s physiology is critical for enhancing the understanding of bioinorganic chemistry but few high-fidelity probes are available. Here we develop fluorescence X-ray absorption near-edge structure tomography as a means for studying the spatial arrangement of biological coordination chemistry within intact organisms, and demonstrate the approach by mapping the distribution of cuprous and cupric complexes within Drosophila melanogaster. [ABSTRACT FROM AUTHOR]

Kinesio® Tex tape (KTT) is used in a variety of clinical settings. The purpose of this study was to investigate the effect of KTT from randomized controlled trials (RCTs) in the management of clinical conditions. A systematic literature search of CINAHL; MEDLINE; OVID; AMED; SCIENCE DIRECT; PEDRO; www.internurse.com; SPORT DISCUS; BRITISH NURSING INDEX; www.kinesiotaping.co.uk; www.kinesiotaping.com; COCHRANE CENTRAL REGISTER OF CLINICAL TRIALS; and PROQUEST was performed up to April 2012. The risk of bias and quality of evidence grading was performed using the Cochrane collaboration methodology. Eight RCTs met the full inclusion/exclusion criteria. Six of these included patients with musculoskeletal conditions; one included patients with breast-cancer-related lymphedema; and one included stroke patients with muscle spasticity. Six studies included a sham or usual care tape/bandage group. There was limited to moderate evidence that KTT is no more clinically effective than sham or usual care tape/bandage. There was limited evidence from one moderate quality RCT that KTT in conjunction with physiotherapy was clinically beneficial for plantar fasciitis related pain in the short term; however, there are serious questions around the internal validity of this RCT. There currently exists insufficient evidence to support the use of KTT over other modalities in clinical practice. [ABSTRACT FROM AUTHOR]

It is commonly theorised that patellofemoral pain syndrome (PFPS) is caused by maltracking due to vastus medialis (VM) weakness relative to the vastus lateralis (VL). Despite this being a controversial theory, patellar taping is a commonly used technique that purports to correct this muscle imbalance by increasing the VM/VL ratio. The effects of different forms of taping on vasti muscle activity are still not known. The objective of this study was to investigate the effects of three different types of patellar taping on the VM/VL ratio in asymptomatic university students. Each participant performed a set of four single–legged squats under four separate taping conditions: A) medial, B) lateral, C) neutral, and D) no-tape. The condition sequence was randomised. The main outcome measure was the normalised VM/VL ratio, assessed by using surface electromyography.Secondary outcome measures were the normalised EMG activity of the VM and the VL. A convenience sample of 24 (17 females) students (22 ± 10 years, M ± SD) completed this study. The lateral taping condition produced small but significantly greater VM/VL ratios than the medial (p = 0.007) and neutral (p = 0.007) but not the no-tape (p = 0.123) condition. There were no significant differences between the medial, neutral, and no-tape conditions. These results question whether patellar taping can impart a clinically significant effect on the VM/VL ratio. The results of this study cannot be directly extrapolated to a patient population, and further research in the PFPS population is required before clinical recommendations can be made. [ABSTRACT FROM AUTHOR]

Proton-induced X-ray emission (PIXE) has been used to characterize the multielement chemistry of the diverse fluid inclusions found in intrusion-related gold systems in the Tintina gold province, Yukon and Alaska. The studied samples are from shallow-level examples that contain coexisting brine (type 3) and carbon dioxide-bearing vapor (type 4) inclusions (e.g., Shotgun, Donlin Creek Dome area, Mike Lake, and Brewery Creek) and deeper level deposits (e.g., Pogo, Dublin Gulch, and Emerald Lake) that contain low-salinity carbon dioxide-(type 1) and/or methane-rich (type 5) inclusions, which locally are overprinted by late secondary type 3 inclusions (e.g., Pogo and Emerald Lake). Major element ratios, K/Ca and Mn/Fe, of both synore high-salinity (type 3) and low-salinity (types 1, 4, and 5) inclusions are >1 and <0.24, respectively. The latter is consistent with the reduced conditions in which intrusion-related gold systems form. Late, secondary type 3 inclusions at Emerald Lake and Pogo, however; are chemically distinct, with higher Mn/Fe ratios (>0.24), and at Pogo low K/Ca ratios (<0.2). Chlorine and bromine data have been used to trace the source of salinity. Two distinct groups of Br/Cl mol ratio are recognized. Group 1 includes type 3 inclusions from the Pogo region, Mike Lake, Brewery Creek, and Emerald Lake, which have Br/C1 mol ratios consistent with typical magmatic values, mostly above 0.5 x 10-3 and below 1.54 x 10-3 (seawater). Group 2 comprises type 3 inclusions from Donlin Creek and Shotgun in southwestern Alaska, which have Br/Cl mol ratios from 2.34 x 10-3 to 6.37 x 10-3, potentially reflecting a halogen contribution from the local sedimentary crust (the Kuskokwim basin) considered to be the primary source of the granite melts. The data also provide insights into important metal contents of the fluid inclusions, including copper, zinc, lead, tungsten, and arsenic; however, gold, bismuth and antimony were all below the detection limits for these elements by the PIXE technique. The results explain some of the distinct metal associations of shallow and deep intrusion-related gold systems. Fluid inclusions in deposits emplaced at shallow crustal levels are characterized by higher iron, manganese, zinc, and lead contents due to the greater abundance of chlorine. Tungsten is more elevated in the low-salinity, carbon dioxide-bearing fluid inclusions in deposits at deeper levels, consistent with high tungsten in the deposits and likely due to the formation of tungstate rather than chloride complexes. Copper and arsenic have similar concentrations in both low- and high-salinity inclusions, also suggesting that ligands other than chlorine were important for these elements. Experimental and microanalytical studies have shown that copper, arsenic, and gold can complex with sulfur and do not require chlorine, exclusively, for metal transport. This may explain why deposits at both shallow and deep levels contain gold despite the wide variation in salinity and different fluid types present. [ABSTRACT FROM AUTHOR]

The X-ray spectra of pure elements, excited using MeV energy beam of protons from the nuclear microprobe, have known spectra signatures. This makes X-ray spectra for more complex mixtures amenable to decomposition into contributions from the component elements. By devising this procedure as a matrix operation that transforms directly from spectrum vector to elemental concentration vector, the decomposition can be performed very efficiently enabling the real-time projection of the component element signals. In the case of a raster-scanned beam, with data that contain position information for each X-ray event, this approach enables the real-time projection of component element spatial distribution images. This paper describes the matrix transform approach called dynamic analysis (DA), which enables on-line real-time imaging of major and trace elements using proton-induced X-ray emission (PIXE). The method also provides off-line iterative yield corrections to these images to compensate for changing sample composition across an image area. The resulting images are quantitative in two respects: (1) they resolve the pure element components and strongly reject interferences from other elements and (2) they can be directly interrogated for sample composition at each pixel, over areas, or along lines across the image area, with accuracy comparable to microanalytical point analysis methods. The paper describes the DA method, presents tests, and discusses its application to quantitative major and trace element imaging in geology. © 2001 John Wiley & Sons, Inc. Int J Imaging Syst Technol 11, 219–230, 2000 [ABSTRACT FROM AUTHOR]

Heavy-mineral concentrates (garnets, chromites) and xenoliths from 21 Cretaceous-Tertiary kimberlite intrusions have been used to map the lithospheric mantle beneath the Lac de Gras area in the central part of the Slave Province. Analyses of Nickel Temperature (TNi) and Zinc Temperature (TZn) have been used to place garnet and chromite xenocrysts, respectively, in depth context. Paleogeotherms derived from both xenoliths and concentrates lie near a 35 mW/m2 conductive model at T <= 900°C, and near a 38 mW/m2 model at higher T, implying a marked change in conductivity and/or a thermal transient. Plots of garnet composition vs TNi also show a sharp discontinuity in mantle composition at 900°C. Garnets from <145 km depth are ultradepleted in Y, Zr, Ti and Ga, whereas those from greater depths (to >= 200 km) are similar to garnets from Archean mantle world-wide. Relative abundances of garnet types indicate that the shallow layer consists of ~60% (clinopyroxene-free) harzburgite and 40% lherzolite, whereas the deeper layer contains 15-20% harzburgite and 80-85% lherzolite. T estimates on eclogite xenoliths show that all were derived from the deeper layer. Xenolith data and garnet compositions indicate that the shallow layer is more magnesian (Fo92-94) than the deeper layer (Fo91-92), and both layers are more olivine rich than South African or Siberian Archean peridotite xenoliths. The composition and sharply defined structure of the Lac de Gras lithosphere are unique within our current knowledge of Archean mantle sections. The shallow layer of this lithosphere section is similar to peridotites from some highly depleted ophiolites from convergent-margin settings, and may have formed in a similar situation during the accretion of the Hackett and Contwoyto terranes (magmatic arc and accretionary prism, respectively) to the ancient continental Anton terrane at 2·6-2·7 Ga. The deeper layer is interpreted as a plume head, which rose from the lower mantle and underplated the existing lithosphere at 2·6 Ga; evidence includes a high proportion of the superdeep inclusion assemblage (ferropericlase-perovskite) in the diamond population. This event could have provided heat for generation of the widespread 2·6 Ga post-tectonic granites. Proterozoic subduction from east and west may have modified the cratonic root, mainly by introduction of eclogites near its base. [ABSTRACT FROM PUBLISHER]

Chrome-pyrope garnet is a minor but widespread phase in ultramafic rocks of the continental lithosphere; its complex chemistry preserves a record of events related to fluid movements in the mantle, including melt extraction and metasomatism. We have examined the major-element and trace-element composition of >12 600 Cr-pyrope (Cr2O3 > 1 wt %) xenocrysts in volcanic rocks to evaluate their compositional ranges and interelement relationships. Samples have been divided into three major groups (Archon, >= 2·5 Ga; Proton, 2·5-1 Ga; Tecton, <1 Ga) depending on the age of the last major tectonothermal event in the crust penetrated by the host volcanic rock. Relative depths of garnets within each sample have been determined by measurement of Nickel Temperature (TNi). Mn, Ni and Zn contents of Cr-pyrope garnets are controlled by T-dependent partitioning between garnet and mantle olivine. The expected correlation of mg-number with T is largely masked by effects of bulk composition and crystal chemistry. The Cr content of garnet is a primary indicator of the degree of depletion of the host rock; Fe, Y, Ti and Ga show negative correlations with Cr, suggesting that all have been removed as part of the primary depletion process. In garnets with TNi < 1200°C, the average degree of depletion as measured by these elements decreases from Archon to Proton to Tecton. High-temperature metasomatism, reflecting the introduction of asthenospheric melts, produces strong positive correlations between Fe, Zr, Ti, Y and Ga, and leads to `refertilization' of previously depleted rocks. The prominent Ca-Cr correlation (`lherzolite trend') seen in garnets from clinopyroxene-bearing rocks is controlled primarily by the Cr/Al of the host rock, and Ca shows a strong negative association with Mg. The position and slope of the lherzolite trend vary with temperature and tectonic setting, suggesting that the P/T ratio exerts a control on Ca/Cr in lherzolite garnets. Garnets with less Ca than the lherzolite trend (`subcalcic garnets') are largely confined to Archon suites, where they typically are concentrated in the 130-180 km depth range. The few subcalcic garnets from Proton suites typically are lower in Cr and occur at shallower depths (100-120 km). Subcalcic garnets are absent in Tecton suites analysed in this work. The complexity of the geochemical relationships illustrated here, and their variation with temperature and tectonic setting, suggests that it is possible to define meaningful compositional populations of garnets, which can be used to map the stratigraphy and structure of the lithospheric mantle. [ABSTRACT FROM PUBLISHER]