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1.
Musculoskeletal sarcomas represent rare heterogenous malignancies of mesenchymal origin that can be divided in two distinct subtypes, bone and soft tissue sarcomas. Current treatment options combine the surgical excision of local tumors and multidrug chemotherapy to prevent metastatic widespread disease. Due to the grim prognosis that usually accompanies such tumors, researchers have attempted to shed light on the molecular pathways implicated in their pathogenesis in order to develop novel, innovative, personalized therapeutic strategies. Erythropoietin-producing human hepatocellular receptors (EPHs) are tyrosine-kinase transmembrane receptors that, along with their ligands, ephrins, participate in both tumor-suppressive or tumor-promoting signaling pathways in bone and soft tissue sarcomas. The EPH/ephrin axis orchestrates cancerous processes such as cell–cell and cell–substrate adhesion and enhances the remodeling of the intracellular cytoskeleton to stimulate the motility and invasiveness of sarcoma cells. The purpose of our study was to review published PubMed literature to extract results from in vitro, in vivo and clinical trials indicative of the role of EPH/ephrin signaling in bone and soft tissue sarcomas. Based on these reports, significant interactions between the EPH/ephrin signaling pathway and a plethora of normal and abnormal cascades contribute to molecular mechanisms enhancing malignancy during sarcoma progression. In addition, EPHs and ephrins are prospective candidates for diagnostic, monitoring and therapeutic purposes in the clinical setting against bone and soft tissue sarcomas.  相似文献   
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Unbalanced charge injection is deleterious for the performance of colloidal quantum dot (CQD) light‐emitting diodes (LEDs) as it deteriorates the quantum efficiency, brightness, and operational lifetime. CQD LEDs emitting in the infrared have previously achieved high quantum efficiencies but only when driven to emit in the low‐radiance regime. At higher radiance levels, required for practical applications, the efficiency decreased dramatically in view of the notorious efficiency droop. Here, a novel methodology is reported to regulate charge supply in multinary bandgap CQD composites that facilitates improved charge balance. The current approach is based on engineering the energetic potential landscape at the supra‐nanocrystalline level that has allowed to report short‐wave infrared PbS CQD LEDs with record‐high external quantum efficiency in excess of 8%, most importantly, at a radiance level of ≈5 W sr?1 m2, an order of magnitude higher than prior reports. Furthermore, the balanced charge injection and Auger recombination reduction has led to unprecedentedly high operational stability with radiance half‐life of 26 068 h at a radiance of 1 W sr?1 m?2.  相似文献   
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The paper introduces a novel detection and tracking system that provides both frame-view and world-coordinate human location information, based on video from multiple synchronized and calibrated cameras with overlapping fields of view. The system is developed and evaluated for the specific scenario of a seminar lecturer presenting in front of an audience inside a “smart room”, its aim being to track the lecturer’s head centroid in the three-dimensional (3D) space and also yield two-dimensional (2D) face information in the available camera views. The proposed approach is primarily based on a statistical appearance model of human faces by means of well-known AdaBoost-like face detectors, extended to address the head pose variation observed in the smart room scenario of interest. The appearance module is complemented by two novel components and assisted by a simple tracking drift detection mechanism. The first component of interest is the initialization module, which employs a spatio-temporal dynamic programming approach with appropriate penalty functions to obtain optimal 3D location hypotheses. The second is an adaptive subspace learning based 2D tracking scheme with a novel forgetting mechanism, introduced to reduce tracking drift and increase robustness. System performance is benchmarked on an extensive database of realistic human interaction in the lecture smart room scenario, collected as part of the European integrated project “CHIL”. The system consistently achieves excellent tracking precision, with a 3D mean tracking error of less than 16 cm, and is demonstrated to outperform four alternative tracking schemes. Furthermore, the proposed system performs relatively well in detecting frontal and near-frontal faces in the available frame views. This work was performed while Zhenqiu Zhang was on a summer internship with the Human Language Technology Department at the IBM T.J. Watson Research Center.  相似文献   
4.
Cork taint, one of the most known off-flavours in wine, is usually attributed to the presence of the aromatic compound 2,4,6-trichloroanisole (2,4,6-TCA) in cork stoppers made from the bark of the cork oak, Quercus suber. There are many major chemical/biochemical pathways through which 2,4,6-TCA can be formed during cork production. The estimated incidence of cork-tainted wine bottles ranges from 2–to 7%, costing global wine industry approximately US$ 10 billion annually. During this study, a laboratory-scale system was designed and constructed, to efficiently treat cork bark and stopper samples using ozone and/or other sterilizing gases, such as steam, via sequential application of pulsed vacuum–pressure cycles. The developed physicochemical processes were studied and evaluated in order to achieve both sterilization conditions and 2,4,6-TCA removal without affecting the mechanical and bottling properties of cork. According to the results, the application of ozone alone seems to be a promising treatment method for cork barks. However, the pulsed treatment ensures both sufficient removal (99%) of both bacteria and moulds from cork stoppers when combined with ozone or steam and satisfactory deodorization of cork stoppers achieving high percentages (90%) of 2,4,6-TCA removal when combined with steam. The operating cost of each alternative process (plain or pulsed, with or without ozone and/or steam) was estimated and compared, in laboratory scale, for the selection of the most efficient process, taking into account technicoeconomical aspects.  相似文献   
5.
In this paper a systematic methodology is presented for the simultaneous optimal selection of raw materials, fossil fuels and alternative fuels in cement production. The aim is to offer a generic mathematical formulation that can be used as the basis for developing case specific mathematical formulations that can assist the strategic decision-making process. The mathematical model presented takes into consideration the essential elements of a cement plant operation. The final formulation is a mixed integer linear programming problem that aims at minimizing the overall operating cost. A realistic case study is presented which demonstrates the usefulness of the proposed mathematical programming methodology.  相似文献   
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The aim of the present study was to assess the influence of substrate concentration on the fermentative hydrogen production from sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time (HRT) of 12 h and carbohydrate concentrations ranging from 9.89 to 20.99 g/L, in glucose equivalents. The maximum hydrogen production rate and yield were obtained at the concentration of 17.50 g carbohydrates/L and were 2.93 ± 0.09 L H2/L reactor/d and 0.74 ± 0.02 mol H2/mol glucose consumed, corresponding to 8.81 ± 0.02 L H2/kg sweet sorghum, respectively. The main metabolic product at all steady states was butyric acid, while ethanol production was high at high substrate concentrations. The experiments showed that hydrogen productivity depends significantly on the initial carbohydrate concentration, which also influences the distribution of the metabolic products.  相似文献   
8.
This paper studies neural structures with weights that follow the model of the quantum harmonic oscillator (Q.H.O.). The proposed neural networks have stochastic weights which are calculated from the solution of Schrödinger’s equation under the assumption of a parabolic (harmonic) potential. These weights correspond to diffusing particles, which interact to each other as the theory of Brownian motion (Wiener process) predicts. The learning of the stochastic weights (convergence of the diffusing particles to an equilibrium) is analyzed. In the case of associative memories the proposed neural model results in an exponential increase of patterns storage capacity (number of attractors). Finally, it is shown that conventional neural networks and learning algorithms based on error gradient can be conceived as a subset of the proposed quantum neural structures. Thus, the complementarity between classical and quantum physics is also validated in the field of neural computation.  相似文献   
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