A learning curve model has been developed to analyze the mass production cost structure of proton exchange membrane fuel cells for automobiles. The fuel cell stack cost is aggregated by the cost of ...membranes, platinum, electrodes, bipolar plates, peripherals and assembly process. The mass production effects on these components are estimated. Nine scenarios with different progress ratios and future power densities are calculated by the learning curve for cumulative production of 50
000 and 5 million vehicles. The results showed that the fuel cell stack cost could be reduced to the same level as that of an internal combustion engine today, and that the key factors are power density improvement and mass production process of bipolar plates and electrodes for reducing total cost of fuel cell stack.
We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed ...apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.
Observations of strong flux of low-energy neutrons were made by 3He counters during thunderstorms (Gurevich et al., 2012) 11. How the unprecedented enhancements were produced remains elusive. To ...better elucidate the mechanism, a simulation study of surrounding material impacts on measurement by 3He counters was performed with GEANT4. It was found that unlike previously thought, a 3He counter had a small sensitivity to high-energy gamma rays because of inelastic interaction with its cathode-tube materials (Al or stainless steel). A 3He counter with the intrinsic small sensitivity, if surrounded by thick materials, would largely detect thunderstorm-related gamma rays rather than those neutrons produced via photonuclear reaction in the atmosphere. On the other hand, the counter, if surrounded by thin materials and located away from a gamma-ray source, would observe neutron signals with little gamma-ray contamination. Compared with the Gurevich measurement, the present work allows us to deduce that the enhancements are attributable to gamma rays, if their observatory was very close to or inside a gamma-ray emitting region in thunderclouds.
Open wedge high tibial osteotomy (OWHTO) for medial-compartment osteoarthritis of the knee can be complicated by intra-operative lateral hinge fracture (LHF). We aimed to establish the relationship ...between hinge position and fracture types, and suggest an appropriate hinge position to reduce the risk of this complication.
Consecutive patients undergoing OWHTO were evaluated on coronal multiplanar reconstruction CT images. Hinge positions were divided into five zones in our new classification, by their relationship to the proximal tibiofibular joint (PTFJ). Fractures were classified into types I, II, and III according to the Takeuchi classification.
Among 111 patients undergoing OWHTOs, 22 sustained lateral hinge fractures. Of the 89 patients without fractures, 70 had hinges in the zone within the PTFJ and lateral to the medial margin of the PTFJ (zone WL), just above the PTFJ. Among the five zones, the relative risk of unstable fracture was significantly lower in zone WL (relative risk 0.24, confidence interval 0.17 to 0.34).
Zone WL appears to offer the safest position for the placement of the osteotomy hinge when trying to avoid a fracture at the osteotomy site. Cite this article:
2017;99B10:1313-18.
Implant-related infection is one of the leading reasons for failure in orthopaedics and trauma, and results in high social and economic costs. Various antibacterial coating technologies have proven ...to be safe and effective both in preclinical and clinical studies, with post-surgical implant-related infections reduced by 90% in some cases, depending on the type of coating and experimental setup used. Economic assessment may enable the cost-to-benefit profile of any given antibacterial coating to be defined, based on the expected infection rate with and without the coating, the cost of the infection management, and the cost of the coating. After reviewing the latest evidence on the available antibacterial coatings, we quantified the impact caused by delaying their large-scale application. Considering only joint arthroplasties, our calculations indicated that for an antibacterial coating, with a final user's cost price of €600 and able to reduce post-surgical infection by 80%, each year of delay to its large-scale application would cause an estimated 35 200 new cases of post-surgical infection in Europe, equating to additional hospital costs of approximately €440 million per year. An adequate reimbursement policy for antibacterial coatings may benefit patients, healthcare systems, and related research, as could faster and more affordable regulatory pathways for the technologies still in the pipeline. This could significantly reduce the social and economic burden of implant-related infections in orthopaedics and trauma.
: C. L. Romanò, H. Tsuchiya, I. Morelli, A. G. Battaglia, L. Drago. Antibacterial coating of implants: are we missing something?
2019;8:199-206. DOI: 10.1302/2046-3758.85.BJR-2018-0316.
The present paper gives an overview and review on self-organized TiO2 nanotube layers and other transition metal oxide tubular structures grown by controlled anodic oxidation of a metal substrate. We ...describe mechanistic aspects of the tube growth and discuss the electrochemical conditions that need to be fulfilled in order to synthesize these layers. Key properties of these highly ordered, high aspect ratio tubular layers are discussed. In the past few years, a wide range of functional applications of the layers have been explored ranging from photocatalysis, solar energy conversion, electrochromic effects over using the material as a template or catalyst support to applications in the biomedical field. A comprehensive view on state of the art is provided.
During a winter thunderstorm on 24 November 2017, a strong burst of gamma rays with energies up to ∼10 MeV was detected coincident with a lightning discharge, by scintillation detectors installed at ...the Kashiwazaki-Kariwa Nuclear Power Station at sea level in Japan. The burst had a subsecond duration, which is suggestive of photoneutron production. The leading part of the burst was resolved into four intense gamma-ray bunches, each coincident with a low-frequency radio pulse. These bunches were separated by 0.7-1.5 ms, with a duration of ≪1 ms each. Thus, the present burst may be considered as a "downward" terrestrial gamma-ray flash (TGF), which is analogous to upgoing TGFs observed from space. Although the scintillation detectors were heavily saturated by these bunches, the total dose associated with them was successfully measured by ionization chambers, employed by nine monitoring posts surrounding the power plant. From this information and Monte Carlo simulations, the present downward TGF is suggested to have taken place at an altitude of 2500±500 m, involving 8_{-4}^{+8}×10^{18} avalanche electrons with energies above 1 MeV. This number is comparable to those in upgoing TGFs.
Giant cell tumor of bone (GCTB) is a rare primary bone tumor, characterized by osteoclast-like giant cells that express receptor activator of nuclear factor-kappa B (RANK), and stromal cells that ...express RANK ligand (RANKL), a key mediator of osteoclast activation. A RANKL-specific inhibitor, denosumab, was predicted to reduce osteolysis and control disease progression in patients with GCTB.
Seventeen patients with GCTB were enrolled. Patients were treated with denosumab at 120 mg every 4 weeks, with a loading dose of 120 mg on days 8 and 15. To evaluate efficacy, objective tumor response was evaluated prospectively by an independent imaging facility on the basis of prespecified criteria.
The proportion of patients with an objective tumor response was 88% based on best response using any tumor response criteria. The proportion of patients with an objective tumor response using individual response criteria was 35% based on the modified Response Evaluation Criteria in Solid Tumors (RECIST) criteria, 82% based on the modified European Organization for Research and Treatment of Cancer (EORTC) criteria, and 71% based on inverse Choi criteria. The median time of study treatment was 13.1 months.
The findings demonstrate that denosumab has robust clinical efficacy in the treatment of GCTB.
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