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ON IRREGULAR SASAKI-EINSTEIN METRICS IN DIMENSION 5
No full textWe show that there are no irregular Sasaki-Einstein structureson rational homology 5-spheres. On the other hand, using K-stability weprove the existence of continuous families of non-toric irregular Sasaki-Einsteinstructures on odd connected sums of S2 × S3
Photons, Protons, SBRT, Brachytherapy- What is leading the charge for the management of prostate cancer? A Perspective From the GU Editorial Team
No full textSeismic geomorphology and evolution of the Melville Bugt Trough Mouth Fan, northwest Greenland
No full textTrough mouth fans on glaciated margins are a common sedimentary feature that contain a 25 record of ice sheet advance and retreat across the continental shelf. This study uses 2D and 3D seismic reflection data across the Melville Bugt Trough Mouth Fan (MB-TMF), offshore northwest Greenland, to document its stratigraphic architecture, glacigenic landforms, and marine deposits. The MB-TMF stratigraphy is characterised by rapid progradation of the continental shelf (over 100 km since ~2.7 Ma) and heterogeneous truncation or subsidence of topset strata. The variable topset character relates to the repeated growth and retreat of the Greenland Ice Sheet across the shelf since ~2.7 Ma. Seismic geomorphology and facies analysis of the prograding clinoforms show repeated sequences of debris flow deposits and gullies that are taken to infer gravity-driven processes and the presence of meltwater-related hyperpycnal flows in areas proximal to the ice sheet on the outer shelf. Several sets of mega-scale glacial lineations confirm the presence and flow pathways of successive ice streams since ~1.3 Ma. Bottomset contourites provide insights into the evolution of the West Greenland Current in Baffin Bay through the Pleistocene, with deposition starting at ~1.0 Ma, having ceased at the onset of glaciation at ~2.7 Ma. This suggests there was a major reduction in northward oceanographic heat transport during the Early Pleistocene, before an increase during interglacials after ~1.0 Ma. Evolution of the MB-TMF can be summarised into four stages that were controlled by variations in ice sheet erosion, topographic forcing of ice stream flow, and changes in accommodation related to glacigenic deposition and tectonic subsidence. These results show that during the Middle Pleistocene Transition there is an apparent switch from a meltwater-dominated depositional regime, to one with greater emplacement of materials by ice directly at the palaeo-shelf edge. These results provide significant new detail about the large-scale glacigenic and marine depositional processes during the repeated fluctuations of the northwest Greenland Ice Sheet into Melville Bugt since ~2.7 Ma
The effect of low temperature heat treatment on stress corrosion crack initiation in machined 316L stainless steel in high-temperature hydrogenated water
No full textA notable reduction of the stress corrosion cracking (SCC) initiation susceptibility was identified for machined cold-rolled 316L stainless steel that received a 650 °C/10 hours heat-treatment prior to slow strain rate tensile (SSRT) testing in high-temperature hydrogenated water. The cracks per unit area of the machined surface of heat-treated specimens decreased by ~50% compared to as-machined surfaces, and by >70% with respect to polished surfaces. The results were ascribed to recrystallization of the ultrafine-grains present in the outer deformation layer of the machined surface, which resulted in a reduction of the tensile residual stress and nano-indentation hardness
Hydrocracking of virgin and Post-Consumer Polymers
No full textWith the growing concern around polymer waste sent to landfill and its environmental release, one effective route for polymer recycling is hydrocracking over bifunctional zeolites. Zeolite Beta impregnated with 1% Pt has demonstrated high conversion of single and mixed streams of virgin and post-consumer polymers, LDPE, HDPE, PP and PS under mild reaction conditions of 330°C, 20 bar H2 and a 30 minute reaction time. The PE and PP streams giving a similar mix of low molecular weight hydrocarbons with higher selectivity toward gases (typically, C3-C4) and also, obtaining high iso- to normal paraffin ratio. PS was readily converted into an aromatic-rich product under these mild conditions and demonstrated the ability to be a source of benzene and ethylbenzene for use as raw materials in further polymer production. Dealuminated zeolite USY with 1% Pt increased the selectivity toward liquid products and resulting in more naphtha (C5-C12) and heavier liquids (C13-C20)
Stellar Dynamical Modeling - Accuracy of 3D Density Estimation for Edge-on Axisymmetric Galaxies
No full textFrom Rybicki’s analysis using the Fourier slice theorem, mathematically it is possi-ble to reproduce uniquely an edge-on axisymmetric galaxy’s 3D light distribution from its 2Dsurface brightness. Utilizing galaxies from a cosmological simulation, we examine the abil-ity of Syer and Tremaine’s made-to-measure method and Schwarzschild’s method for stellardynamical modeling to do so for edge-on oblate axisymmetric galaxies. Overall, we find thatthe methods do not accurately recover the 3D distributions, with the made-to-measure methodproducing more accurate estimates than Schwarzschild’s method. Our results have implica-tions broader than just luminosity density, and affect other luminosity-weighted distributionswithin galaxies, for example, age and metallicity
Energy-Efficient Resource Allocation for NOMA-MEC Networks with Imperfect CSI
No full textThe combination of non-orthogonal multiple access (NOMA) and multi-access edge computing (MEC) can significantly improve the system performance including communication coverage, spectrum efficiency, etc. In this paper, we focus on energy-efficient resource allocation for a multi-user multi-BS NOMA-MEC network with imperfect channel state information (CSI), where each user can upload its tasks to multiple base stations (BSs) for remote executions. We propose an optimization scheme, including task assignment, power allocation and user association, to minimize energy consumption. Specifically, we transform the probabilistic problem into a non-probabilistic one. To efficiently solve this nonconvex energy minimization problem, we first investigate the one-user two-BS case and derive the optimal closed-form expressions of task assignment and power allocation via the bilevel programming method. Subsequently, based on the derived optimal solution, we propose a low complexity algorithm for the user association in the multi-user multi-BS scenario. Simulations demonstrate that the proposed algorithm can yield much better performance than the conventional OMA scheme and the identical results with lower complexity from the exhaustive search with the small number of BSs
The importance of keratinocyte-dendritic cell interactions in understanding fragrance allergy
No full textRepolarizing potassium currents in working myocardium of Japanese quail: novel translational model for cardiac electrophysiology
No full textBirds developed endothermy and four-chambered high-performance heart independently from mammals. Though avian embryos are extensively studied and widely used as various models for heart research, little is known about cardiac physiology of adult birds. Meanwhile, cardiac electrophysiology is in search for easily accessible and relevant model objects which resemble human myocardium in the pattern of repolarizing currents (I Kr , I Ks , I Kur and I to ). This study focuses on the configuration of electrical activity and electrophysiological phenotype of working myocardium in adult Japanese quails ( Coturnix japonica ). The resting membrane potential and action potential (AP) waveform in quail atrial myocardium were similar to that in working myocardium of rodents. Using whole-cell patch clamp and sharp glass microelectrodes, we demonstrated that the repolarization of quail atrial and ventricular myocardium is determined by voltage-dependent potassium currents I Kr , I Ks and I to – the later was previously considered as an exclusive evolutionary feature of mammals. The specific blockers of these currents, dofetilide (3 μmol l -1 ), HMR 1556 (30 μmol l -1 ) and 4-aminopyridine (3 mmol l -1 ), prolonged AP in both ventricular and atrial myocardial preparations. The expression of the corresponding channels responsible for these currents, in quail myocardium was investigated with quantitative RT-PCR and western blotting. In conclusion, the described pattern of repolarizing ionic currents and channels in quail myocardium makes this species a novel and suitable experimental model for translational cardiac research and reveals new information related to the evolution of cardiac electrophysiology in vertebrates
A Quantitative Systematic Review of Clinical Outcome Measure Use in Peripheral Nerve Injury of the Upper Limb
No full textBACKGROUND: Peripheral nerve injury (PNI) is common, leading to reduced function, pain, and psychological impact. Treatment has not progressed partly due to inability to compare outcomes between centres managing PNI. Numerous outcome measures exist but there is no consensus on which outcome measures to use nor when.OBJECTIVE: To perform a systematic review in order to describe and classify outcome measures used in PNI.METHODS: A search of Ovid Medline, Ovid Embase, Allied and Complementary Medicine Database (AMED) and CENTRAL (Cochrane Clinical Trials) was conducted. Randomised control trials, cohort studies, case-controlled and case series ( 5 participants) published from inception of the database until 2019 investigating adult patients with a traumatic upper limb peripheral nerve injury in which an outcome measurement was utilised were included.RESULTS: Ninety-six studies were included (15 RCTs, 8 case-control studies, 18 cohort studies, 5 observational studies and the remainder were case-series or retrospective reviews). Fifty-six individual outcome measures were identified, utilised across 28 different countries and 7,097 patients. Ten core domains were defined: sensory subjective, sensory objective, motor subjective, motor objective, sensorimotor function, psychology and wellbeing, disability, quality of life, pain and discomfort, and neurotrophic measures.CONCLUSION: Lack of consensus on outcome measure use hinders comparison of outcomes between nerve injury centres and the development of novel treatments. Development of a core outcome set will help standardise outcome reporting, improve translation of novel treatments from lab to clinical practice, and ensure future research in peripheral nerve injury is more amenable to systematic review and meta-analysis