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51.
Since the discovery of camelid heavy-chain antibodies in 1993, there has been tremendous excitement for these antibody domains (VHHs/sdAbs/nanobodies) as research tools, diagnostics, and therapeutics. Commercially, several patents were granted to pioneering research groups in Belgium and the Netherlands between 1996–2001. Ablynx was established in 2001 with the aim of exploring the therapeutic applications and development of nanobody drugs. Extensive efforts over two decades at Ablynx led to the first approved nanobody drug, caplacizumab (Cablivi) by the EMA and FDA (2018–2019) for the treatment of rare blood clotting disorders in adults with acquired thrombotic thrombocytopenic purpura (TPP). The relatively long development time between camelid sdAb discovery and their entry into the market reflects the novelty of the approach, together with intellectual property restrictions and freedom-to-operate issues. The approval of the first sdAb drug, together with the expiration of key patents, may open a new horizon for the emergence of camelid sdAbs as mainstream biotherapeutics in the years to come. It remains to be seen if nanobody-based drugs will be cheaper than traditional antibodies. In this review, I provide critical perspectives on camelid sdAbs and present the promises and challenges to their widespread adoption as diagnostic and therapeutic agents. 相似文献
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The proper placement of visual sensors across a sensor field for covering targets with arbitrary location and orientation is a mission-critical decision in surveillance applications. The specifics of sensor deployment in these applications not only determine the maximum achievable coverage, but it also affects the quality of the target’s appearance in cameras for subsequent use in vision tasks. However, the inaccuracies inherent in localization techniques and the lack of knowledge regarding the target orientation render existing proposals insufficient for real-life scenarios. In this paper, we address both challenges. First, we extend the conventional point representation of targets with a circular model to account for full-angle coverage of targets with known location yet with unknown orientation from all directions. We then assume, in the absence of precise location information, a trajectory profile of targets could instead be generated through the importance sampling of the environment, indicating spots where the target is most likely located. This profile-based abstraction enables us to capture the uncertainty in target’s location by encircling every agglomeration of proximal samples within one cluster. Each cluster can then be viewed as a virtual macroscopic circular target for which we formulate the coverage problem in terms of a Binary Integer Programming (BIP) model. We have also taken into account the presence of obstruction in between multiple targets by calculating the angles of view of the sensors in an occlusion-dependant manner, effectively determining optimal placement for maximal instead of full-angle coverage. Evaluation results derived from our simulation experiments reveal that the proposed mechanism can effectively achieve high coverage accuracy with minimum number of deployed sensors. 相似文献
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Application of natural fibre composites is going to increase in different areas caused by environmental, technical and economic advantages. However, their low mechanical properties have limited their particular application in automotive structural components. Hybridizations with other reinforcements or matrices can improve mechanical properties of natural fibre composite. Moreover, geometric optimizations have a significant role in structural strength improvement. This study focused on selecting the best geometrical bumper beam concept to fulfill the safety parameters of the defined product design specification (PDS). The mechanical properties of developed hybrid composite material were considered in different bumper beam concepts with the same frontal curvature, thickness, and overall dimensions. The low-speed impact test was simulated under the same conditions in Abaqus V16R9 software. Six weighted criteria, which were deflection, strain energy, mass, cost, easy manufacturing, and the rib possibility were analyzed to form an evaluation matrix. Topsis method was employed to select the best concept. It is concluded that double hat profile (DHP) with defined material model can be used for bumper beam of a small car. In addition, selected concept can be strengthened by adding reinforced ribs or increasing the thickness of the bumper beam to comply with the defined PDS. 相似文献
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Kok Kee Yang M. R. Mahmoudian Mehdi Ebadi Hun Lee Koay Wan Jeffrey Basirun 《Metallurgical and Materials Transactions B》2011,42(6):1274-1279
Voltammetry and chronoamperometry for the electrodeposition of tin from Tin(II) methane sulfonate mixed with ionic liquid and methane sulfonate acid at room temperature was studied. Cyclic voltammetry shows redox waves of Tin(II), which proves that the electrodeposition of tin from Tin(II) methane sulfonate is a diffusion-controlled process. The diffusion coefficient of Tin(II) ions in the solvent mixture showed good agreement from both voltammetry and chronoamperometry results. The diffusion coefficient of Tin(II) in the mixture was much smaller than in aqueous solution, and it depends on the anion of the ionic liquid. 相似文献
56.
Mehdi Ebadi Wan J. Basirun Yatimah Alias Mohammad R. Mahmoudian 《Metallurgical and Materials Transactions A》2011,42(8):2402-2410
The codeposition of Ni-Co-Fe-Zn alloys from a mixture of 1-ethyl-3-methylimidazolium chloride (EMIC)/ethylene glycol (EG) was studied using potentiostatic electrodeposition in the potential range of –1.10 and –1.30 V vs saturated calomel electrode (SCE), using a permanent parallel magnetic field (PPMF) of 9 T. The uniform magnetic field was aligned parallel to the cathode surface. It was found that both normal and anomalous codeposition occurred. Films with different elemental percentage and deposit morphology were obtained from a mixture of EMIC/EG solution at the applied potentials (–1.10 and –1.30 V) in the absence and presence of a PPMF. The influence of magnetic field on the nucleation and growth process is studied with respect to the magneto-hydrodynamic effect (MHD) and applied potentials. 相似文献
57.
In this paper, a laminated composite plate is analyzed using a multiscale method. At first, material properties of a lamina are obtained using an analytical micromechanical approach called simplified unit cell method (SUCM), and then in structural level, the generalized differential quadrature method (GDQM) is used to analyze a laminated composite plate. By means of the Boltzmann superposition principle, the viscoelastic behavior of the matrix is obtained. The Prony series is considered to define the compliance of matrix. To verify the results, graphiteT300/epoxy5208 composite material is analyzed and the results are compared with existing experimental data. The multiscale algorithm includes obtaining overall properties of the composite by SUCM; then, these properties are used to define the bending stiffness. Governing equations of motion of laminated composite plate are solved via GDQM and Newton–Raphson method. Variations of stresses and displacements versus time and volume fraction of the fibers are shown for laminated composite plates with different boundary conditions. 相似文献
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Introducing a specific clean extraction procedure with a minimal matrices effect for food colorant determination is still a challengeable topic and highly recommended. Mixed hemimicelle solid-phase extraction method, based on cetyltrimethylammonium bromide-coated Fe3O4/SiO2 nanoparticles as a novel, simple, and fast preconcentration method, was applied for preconcentration and fast isolation of three synthetic food colorants in foodstuff matrices prior to HPLC-UV-vis determination. The influence of different parameters on extraction efficiency such as surfactant amount, sample pH, time of extraction, desorption condition, and nanoparticles concentration was optimized. Under the optimized conditions, a preconcentration factor of 100 was achieved by extracting 10 mL sample. The limit of detection for the three synthetic food colorants including Tartrazine, Sunset yellow FCF, and Quinoline yellow is 2.50, 1.25, and 2.12 μg/L, respectively. The proposed method was applicable for extraction and preconcentration of three food colorants in various food samples with the food dye contents in the range of 13–105 μg/L. 相似文献