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671.
Galectin-1 is a β-galactoside-binding lectin with manifold biological functions. A single tryptophan residue (W68) in its carbohydrate binding site plays a major role in ligand binding and is highly conserved among galectins. To fine tune galectin-1 specificity, we introduced several non-canonical tryptophan analogues at this position of human galectin-1 and analyzed the resulting variants using glycan microarrays. Two variants containing 7-azatryptophan and 7-fluorotryptophan showed a reduced affinity for 3’-sulfated oligosaccharides. Their interaction with different ligands was further analyzed by fluorescence polarization competition assay. Using molecular modeling we provide structural clues that the change in affinities comes from modulated interactions and solvation patterns. Thus, we show that the introduction of subtle atomic mutations in the ligand binding site of galectin-1 is an attractive approach for fine-tuning its interactions with different ligands.  相似文献   
672.
In this paper, we report the synthesis of Cr2AlC by using biochars derived from lignin, Distiller's dried grains with solubles (DDGS), and hemp fibers. Initially, the powders were pyrolyzed at 1350°C for 4 h in Ar atmosphere to form biochars. The ball-milled and sieved biochar powders were then mixed with Cr and Al powders in different stoichiometric ratios according to the C-content of the biochars. The mixed powders were reacted at 1350°C for 4 h in Ar atmosphere. Detailed scanning electron microscopy and X-ray diffraction analysis showed the powders derived from hemp and DDGS biochars were > 90% pure as compared to powders derived from lignin biochar which was 76% pure. It is expected that ternary ceramics derived from biochars can be an addition avenue for carbon-storage.  相似文献   
673.
A smart community grid is an electrical network, which connects several producers, consumers, and prosumers to share energy in an intelligent and secure way. The main challenges of smart community grid are demand response, demand bidding, dynamic electricity tariffs, demand-side management, and prosumers handling. The current state-of-the-art smart grid decision making is focused on consumers and producers behavior while the aim of this research is to achieve prosumer's different goals in an optimized and intelligent way. A genetic algorithm (GA)-based solution is proposed to share energy in an optimized way without affecting the prosumers' preferences. Six prosumers smart community grids data sets are used to validate the performance of the proposed system. The results show that the proposed method significantly improves the loss of energy sharing without compromising the user's preferences.  相似文献   
674.
Neural Computing and Applications - Histopathology imaging is one of the key methods used to determine the presence of cancerous cells. However, determining the results from such medical images is...  相似文献   
675.
Microorganisms display nonequilibrium predator–prey behaviors, such as chasing–escaping and schooling via chemotactic interactions. Even though artificial systems have revealed such biomimetic behaviors, switching between them by control over chemotactic interactions is rare. Here, a spindle-like iron-based metal–organic framework (MOF) colloidal motor which self-propels in glucose and H2O2, triggered by UV light is reported. These motors display intrinsic UV light-triggered fuel-dependent chemotactic interactions, which are used to tailor the collective dynamics of active-passive colloidal mixtures. In particular, the mixtures of active MOF motors with passive colloids exhibit distinctive “chasing–escaping” or “schooling” behaviors, depending on glucose or hydrogen peroxide being used as the fuel. The transition in the collective behaviors is attributed to an alteration in the sign of ionic diffusiophoretic interactions, resulting from a change in the ionic clouds produced. This study offers a new strategy on tuning the communication between active and passive colloids, which holds substantial potentials for fundamental research in active matter and practical applications in cargo delivery, chemical sensing, and particle segregation.  相似文献   
676.
Bipolar membrane electrodialysis (BMED) is considered a state-of-the-art technology for the conversion of salts into acids and bases. However, the low concentration of base generated from a traditional BMED process may limit the viability of this technology for a large-scale application. Herein, we report an especially designed multistage-batch (two/three-stage-batch) BMED process to increase the base concentration by adjusting different volume ratios in the acid (Vacid), base (Vbase), and salt compartments (Vsalt). The findings indicated that performance of the two-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:5 was superior in comparison to the three-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:2. Besides, the base concentration could be further increased by exchanging the acid produced in the acid compartment with fresh water in the second stage-batch process. With the two-stage-batch BMED, the maximum concentration of the base can be obtained up to 3.40 mol∙L–1, which was higher than the most reported base production by BMED. The low energy consumption and high current efficiency further authenticate that the designed process is reliable, cost-effective, and more productive to convert saline water into valuable industrial commodities.  相似文献   
677.
Pattern Analysis and Applications - 3D model reconstruction from single 2D RGB images is a challenging and actively researched computer vision task. Several techniques based on conventional network...  相似文献   
678.
679.
Silicon - This research aims to study the behavior of silica based geopolymeric material (22–28%Si) from granitic waste. Granitic waste in powder form was used as main precursor in...  相似文献   
680.
Neural Computing and Applications - Knowledge graphs (KGs) inherently lack reasoning ability which limits their effectiveness for tasks such as question–answering and query expansion. KG...  相似文献   
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