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Inflammatory arthropathy in the elite sports athlete
No full textElite athletes commonly present with joint pains that are attributed to overuse injuries though on occasion it can be due to an inflammatory arthropathy. The diagnostic challenge is that presenting symptoms of benign injuries are similar to inflammatory arthropathies. A holistic review of the athlete can provide clues suggestive of inflammatory arthropathy, before requesting further investigations to confirm the diagnosis. Current imaging modalities are not specific in differentiating inflammatory arthritis with other causes of joint inflammation. Prompt treatment is required to restore the athlete to an optimum level of activity and prevent career ending disability, all in adherence to the regulations of the sporting governing bodies. This review aims to highlight the importance of inflammatory arthropathy in the differentials for an athlete presenting with joint pains
Is the index efficient? A worldwide tour with stochastic dominance
No full textWe conduct a broad study of stochastic dominance efficiency on financial markets. We show that in the long run the vast majority of 17 equity market indices across the globe are inefficient at order two relative to their industry components. In the short run, the past stochastic dominance relation between the index and sub-indices predicts future dominance. Trading rules accounting for the predictability of stochastic dominance improve the out-of-sample certainty equivalents of risk-averse investors. The gains are especially pronounced for European and developing markets, while no consistent outperformance of alternative strategies is found for the S&P 100 and Nikkei 225 indices
Glacier forelands reveal fundamental plant and microbial controls on short-term ecosystem nitrogen retention
No full text1. Human activities have massively increased the amount of reactive nitrogen in the biosphere, which is leading to increased nitrogen (N) inputs in terrestrial ecosystems. The retention of N is a crucial ecosystem function of both managed and natural ecosystems, and there is a long history of experimental, observational, and conceptual studies identifying its major controls. Yet, the plant and soil microbial controls on the retention of added N remain elusive.2. Here, we used three ecosystem chronosequences in front of retreating glaciers in the European Alps to test our hypothesis that the retention of added reactive 15N increases as succession proceeds, and to identify the plant and microbial controls on ecosystem N retention.3. We found that the uptake and retention of N did not change during succession, despite consistent changes in plant, soil, and microbial properties with increasing time since deglaciation. Instead, we found that plant and microbial properties that remained constant during succession controlled 15N uptake and retention: low root and microbial C/N ratios, as well as high root biomass, increased plant and microbial uptake of added N. In addition, high soil concentrations of nitrate and ammonium reduced the uptake of N in microbes and roots, respectively.4. Synthesis Our results demonstrate that plant and microbial N demand, as well as soil N availability, drive the short-term retention of added N during succession in glacier forelands. This finding represents an advance in our understanding of the fundamental controls on ecosystem N retention and the role of plant-microbial interactions in this process. Such understanding is crucial for predicting and mitigating the response of terrestrial ecosystems to the ever-increasing amounts of reactive N in the biosphere
SOX9 is required for kidney fibrosis and activates NAV3 to drive renal myofibroblast function
No full textRenal fibrosis is a common end point for kidney injury and many chronic kidney diseases. Fibrogenesis dependson the sustained activation of myofibroblasts, which deposit the extracellular matrix that causes progressive scarringand organ failure. Here, we showed that the transcription factor SOX9 was associated with kidney fibrosis in humansand required for experimentally induced kidney fibrosis in mice. From genome-wide analysis, we identified Neuronnavigator 3 (NAV3) as acting downstream of SOX9 in kidney fibrosis. NAV3 increased in abundance and colocalizedwith SOX9 after renal injury in mice, and both SOX9 and NAV3 were present in diseased human kidneys. In an in vitromodel of renal pericyte transdifferentiation into myofibroblasts, we demonstrated that NAV3 was required formultiple aspects of fibrogenesis, including actin polymerization linked to cell migration and sustained activation ofthe mechanosensitive transcription factor YAP1. In summary, our work identifies a SOX9-NAV3-YAP1 axis involvedin the progression of kidney fibrosis and points to NAV3 as a potential target for pharmacological intervention
A structured catalyst support combining electrochemically exfoliated graphene oxide and carbon black for enhanced performance and durability in low-temperature hydrogen fuel cells
No full textReduced electrochemically exfoliated graphene oxide (rEGO) is combined with carbon black (CB) as a hybrid support material to improve platinum (Pt) catalyst electrochemical activity and durability. Pt/rEGO2-CB3 (rEGO/CB ratio 2/3) retains 71% of initial electrochemical surface area (ECSA) and maintains higher oxygen reduction reaction (ORR) activity compared to Pt/CB after 30000 cycles of the accelerated stress test (AST). In addition, Pt/rEGO2-CB3 shows a 1.8 times improvement in the hydrogen fuel cell performance compared with Pt/CB and is more stable after 24 hours at a continuous 0.60 V. The Pt/rEGO2-CB3 promotes the 4e- reaction pathway demonstrated by linear sweep voltammetry (LSV), which leads to greater ORR activity. In addition, the combination of rEGO and CB leads to both enhanced transport properties and improved stability. The Pt particles on both CB and rEGO are less likely to agglomerate in the composite support than in either of the two carbon supports when used alone
Non-conventional phases of colloidal nanorods with a soft corona
No full textUsing computer simulations, we investigate the phase behavior of hard-core spherocylinders with a length-to-diameter ratio L=σ = 5 and coated by a soft deformable corona of length λ=σ = 1:35. When quasi-two-dimensional layers are formed in smectic and solid phases at low temperatures, the competition between the two intrinsic length scales of the parallel aligned particles leads to the stabilization of different in-plane lattices of non-conventional symmetry, including low-density-hexagonal, square and high-density-hexagonal crystals as well as an intriguing dodecagonal quasicrystal. Our study opens up the opportunity of controlling the assembly of anisotropic nanoparticles into structures with pre-engineered symmetry-dependent physical properties
Shell Filling and Trigonal Warping in Graphene Quantum Dots
No full textTransport measurements through a few-electron circular quantum dot in bilayer graphene display bunching of the conductance resonances in groups of four, eight and twelve. This is in accordance with the spin and valley degeneracies in bilayer graphene and an additional threefold 'minivalleydegeneracy' caused by trigonal warping. For small electron numbers, implying a small dot size and a small displacement field, a two-dimensional s- and then a p-shell are successively filled with four and eight electrons, respectively. For electron numbers larger than 12, as the dot size andthe displacement field increase, the single-particle ground state evolves into a three-fold degenerate minivalley ground state. A transition between these regimes is observed in our measurements and can be described by band-structure calculations. Measurements in magnetic field confirm Hund'ssecond rule for spin filling of the quantum dot levels, emphasizing the importance of exchange interaction effects
Enhanced process for energy efficient extraction of 1,3-butadiene from a crude C4 cut
No full text1,3-butadiene is an essential platform chemical for producing rubberlike polymers, which is extracted from C4 hydrocarbons that are produced through steam cracking. The current state of-the-art technology is the BASF process that uses thermally coupled extractive distillation (ED) followed by two distillation columns. However, the process requires high temperature heat input, thus high cost hot utility and reduces the possibility for process heat integration. To solve these issues, this study proposes novel enhancements: the ED part is modified with intermediate heating and the classic columns are replaced with a heat pump assisted dividing wall column (DWC). Rigorous simulations were carried out in Aspen Plus for a typical ED process. The intermediate reboiler system is designed to maximize the possible process heat recovery. The results show that the heat pump assisted DWC is able to reduce the energy intensity of the classic distillation section of the BASF process by 54.8% and reduces the total annual costs by 29.9%. Additionally, the intermediate reboiler reduces the energy intensity of the ED section by 8.3% while also reducing the CAPEX of the system due to the need for a smaller recycle compressor. In combination, these modifications are able to achieve up to a 21% reduction in the energy intensity of the overall process, with a payback time of 1 year
Atomium: The astounding complexity of the near circumstellar environment of the M-type AGB star R Hydrae:I. Morpho-kinematical interpretation of CO and SiO emission
No full textEvolved low to intermediate mass stars are known to shed their gaseous envelope into a large dusty molecule-rich circumstellar nebula which typically develop a high degree of structural complexity. Most of the large-scale, spatially correlated structures in the nebula are thought to originate from the interaction of the stellar wind with a companion. As part of the Atomium large programme, we observed the M-type asymptotic giant branch star R Hydrae with the Atacama Large Millimeter/submillimeter Array (ALMA). The morphology of the inner wind of R Hya —which has a known companion at ∼3500 au — was determined from maps of CO and SiO obtained at high angular resolution. A map of the CO emission reveals a multi-layered structure consisting of a large elliptical feature at an angular scale of ∼10”, that is oriented along the North–South axis. The wind morphology within the elliptical feature is dominated by two hollow bubbles. The bubbles are on opposite sides of the AGB star and lie along an axis with a position angle of ∼115º. Both bubbles are offset from the central star, and its appearance in the SiO channel maps indicates that the two bubbles might be shock waves travelling through the AGB wind. An estimate of the dynamical age of the bubbles yields an age of the order of a hundred years, which is in agreement with the previously proposed elapsed time since the star last underwent a thermal pulse. When the CO and SiO emission is examined on sub-arcsecond angular scales, there is evidence for an inclined, differentially rotating equatorial density enhancement, strongly suggesting the presence of a second nearby companion. The major axis of the position angle of this disk is ∼70º, in the plane of the sky. We tentatively estimate that a lower limit on the mass of the nearby companion is ∼0.65 M, on the basis of the highest measured speeds in the disk and the location of its inner rim at ∼6 au from the AGB star
The additional benefit of professional fluoride application for children as an adjunct to regular fluoride toothpaste: A systematic review and meta-analysis
No full textObjective: To assess whether professional fluoride application (PFA) used in addition to regular fluoride toothpaste (RFT, ≥ 1,000 ppm) is more effective than RFT alone in children.Materials and Methods: A systematic search was conducted using the PubMed, Embase, Google Scholar and CENTRAL databases. Randomized controlled trials (RCTs) comparing the effectiveness of RFT+PFA and RFT alone were included. Meta-analyses with random-effects models were performed. The certainty of evidence was assessed using the GRADE approach.Results: A total of 2,729 records were identified from electronic and manual searches, which were screened by two reviewers independently and in duplicate. Six RCTs (5,034 participants) were included, of which four had high risk of bias and two had unclear risk of bias. The PFA used in all these trials was fluoride varnish (FV). In meta-analyses, no significant difference was observed between participants receiving FV+RFT and RFT alone of d(m/e)fs increment [mean difference (MD) -0.17, 95% confidence interval (CI) -0.60 to 0.26, P = 0.43, I2 = 38%; 6 trials, 5,034 participants, moderate certainty evidence], incidence of caries [risk ratio (RR) 0.91, 95% CI 0.80 to 1.05, P = 0.21, I2 = 41%; 4 trials, 4,487 participants, moderate certainty evidence], or changes in prevalence of caries (RR 0.89, 95% CI 0.78 to 1.01, P = 0.07, I2 = 0%, 4 trials, 4,189 participants, low certainty evidence).Conclusions: Low to moderate certainty evidence suggests that FV does not have significant additional caries-preventive benefit for children (under 8 years old) when provided as an adjunct to daily tooth brushing with RFT (≥ 1,000 ppm). There is insufficient evidence regarding the additional benefit of other PFA interventions