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31.
Porcine reproductive and respiratory syndrome virus (PRRSV) can infect pigs and cause enormous economic losses to the pig industry worldwide. Porcine sialoadhesin (pSN) and CD163 have been identified as key viral receptors on porcine alveolar macrophages (PAM), a main target cell infected by PRRSV. In this study, the protein structures of amino acids 1–119 from the pSN and cSN (cattle sialoadhesin) N-termini (excluding the 19-amino acid signal peptide) were modeled via homology modeling based on mSN (mouse sialoadhesin) template structures using bioinformatics tools. Subsequently, pSN and cSN homology structures were superposed onto the mSN protein structure to predict the binding sites of pSN. As a validation experiment, the SN N-terminus (including the wild-type and site-directed-mutant-types of pSN and cSN) was cloned and expressed as a SN-GFP chimera protein. The binding activity between SN and PRRSV was confirmed by WB (Western blotting), FAR-WB (far Western blotting), ELISA (enzyme-linked immunosorbent assay) and immunofluorescence assay. We found that the S107 amino acid residue in the pSN N-terminal played a crucial role in forming a special cavity, as well as a hydrogen bond for enhancing PRRSV binding during PRRSV infection. S107 may be glycosylated during PRRSV infection and may also be involved in forming the cavity for binding PRRSV along with other sites, including W2, Y44, S45, R97, R105, W106 and V109. Additionally, S107 might also be important for pSN binding with PRRSV. However, the function of these binding sites must be confirmed by further studies.  相似文献   
32.
The magnetocaloric properties of new complex magnetic material La0.65Sr0.35Cu0.1Mn0.9O3, suitable for the Ericsson cycle, have been investigated. For this material, the effect of Cu doping can be attributed to a combination of doping disorder, Cu-Mn super exchange interactions and a site-percolation mechanism, which suppress the metallic conduction and Curie temperature. The Curie temperature decreases to 355 K. The magnetocaloric study exposes a comparable value of the magnetic entropy change for La0.65Sr0.35Cu0.1Mn0.9O3 sample, the value of the maximum entropy change, increases from 1.132 J/kgK to 3.11 J/kgK as magnetic field increases from 1 T to 4 T. A large relative cooling power (RCP) has been observed for La0.65Sr0.35Cu0.1Mn0.9O3. As a result, the studied sample can be considered as potential material for magnetic refrigeration.  相似文献   
33.
Enzyme mimics (or artificial enzymes) have emerged as valuable alternatives to natural enzymes since the pioneering work of Ronald Breslow. They have numerous advantages over natural enzymes, such as high stability, low cost, and tailorable activity. Among varieties of materials explored to mimic enzymes, the inorganic ones, including inorganic complexes and nanomaterials, have attracted increasing interest over the last decade and have the potential to address the current challenges in energy, environment, health, etc.  相似文献   
34.
Amphiphilic block copolymers have been the subject of great scientific interests due to their applications in various fields including nano drug delivery. Three amphiphilic block copolymers based on poly(ε-caprolactone) as a hydrophobic segment and methoxy poly(ethylene oxide) ( as a hydrophilic part were synthesized by the ring-opening polymerization of ε-caprolactone using MeO-PEO5K as macroinitiator by varying initial feed ratios. The synthesized polymers were further explored for their drug delivery potential using clotrimazole as model hydrophobic drug. Drug-loaded micelles were characterized for shape, size, drug encapsulation efficiency, in vitro release, and thermal stability using atomic force microscope, zetasizer, UV–visible spectrophotometry, FTIR, differential scanning calorimetry, and thermogravimetric analysis. Clotrimazole loaded in micelles were also investigated for its antifungal activity through an in vitro assay and scanning electron microscopy. The antifungal activity of drug increased significantly by delivering through polymeric micelles. Current study provides insight into different factors that can be maneuvered to achieve a variety of desired properties of micelles for improved therapeutic efficacy of drugs like clotrimazole. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47769.  相似文献   
35.
Ultra-low power transceiver design is proposed for wireless sensor node used in the wireless sensor network (WSN). Typically, each sensor node contains a transceiver so it is required that both hardware and software designs of WSN node must take care of energy consumption during all modes of operation including active/sleep modes so that the operational life of each node can be increased in order to increase the lifetime of network. The current declared size of the wireless sensor node is of millimeter order, excluding the power source and crystal oscillator. We have proposed a new 2.4 GHz transceiver that has five blocks namely XO, PLL, PA, LNA and IF. The proposed transceiver incorporates less number of low-drop outs (LDOs) regulators. The size of the transceiver is reduced by decreasing the area of beneficiary components up to 0.41 mm2 of core area in such a way that some functions are optimally distributed among other components. The proposed design is smaller in size and consumes less power, <1 mW, compared to other transceivers. The operating voltage has also been reduced to 1 V. This transceiver is most efficient and will be fruitful for the wireless networks as it has been designed by considering modern requirements.  相似文献   
36.
Water conflicts appear when there are insufficient and less available water resources than water demands claimed by different agents. In this study, a new bankruptcy approach is investigated to resolve water conflicts in the Zarrinehroud River Basin, the largest and most important sub-basin of Lake Urmia’s Basin in the northwest of Iran. The new bankruptcy method is compared with the proportional rule (PRO) and another alternative based on the cessation of irrigated agriculture in the region proposed to supply and save environmentally in danger Lake Urmia. Four scenarios consisting of the current situation, optimistic, average and pessimistic scenarios regarding the future of water resources of the basin and agricultural developments were considered. According to the results, both bankruptcy rules helped Lake Urmia to receive more water, but neither could utterly overcome the water shortage of the Lake, so can be used as supplementary actions alongside other solutions. The cessation of irrigated agriculture throughout the basin overcame the average annual shortage of Lake Urmia in the first and second scenarios equal to 137 and 148 million cubic meters respectively. It showed disability to fully supply the lake in the third and fourth scenarios. These three methods must be combined with a social-economic policy like the purchase of decreased water allocations to farmers to be socially acceptable.  相似文献   
37.
The swelling rate and the environmental sensitivity of novel superabsorbent gum arabic–acrylic hydrogel hybrids were investigated. The swelling kinetics of the hydrogel hybrids was studied by means of a Voigt‐based viscoelastic model. The effects of concentration of the initiator, crosslinker, and the monomer ratio on the swelling rate were studied. The superswelling properties of the hydrogel hybrids were evaluated in various environmental pH, salinity and solvent–water mixtures. The optimally prepared hydrogel, MR5, showed a reproducible on–off switching behavior when the swelling medium was alternatively changed between distilled water and alkaline solutions. The hydrogel hybrid MR5 was also tested to be swollen and deswollen alternatively in distilled water and sodium chloride solution. The sorption–desorption behavior was found to be quite repeatable. A similar capability was interestingly observed when a calcium chloride solution with the same molar concentration was used. The swelling changes of the hydrogel hybrid were examined in various water–solvent systems including the aqueous solutions of methanol, ethanol, acetone, ethylene glycol, glycerol, and dimethylsulfoxide. One and/or two volume‐phase transitions were induced by the nonsolvents. The transitions were explained according to the solubility parameters of the solvents and water–solvent mixtures. The swelling–deswelling capability of the hydrogel in alternatively changed solvent–water mixtures was also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5667–5674, 2006  相似文献   
38.
We report here highly dense and pure metallic cadmium (Cd) multifarious prismatic microcrystals (CMPMCs) fabricated by thermal decomposition of cadmium oxide (CdO) powder at 700 °C for 60 min under NH3 gas ambient inside horizontal tube furnace. CMPMCs were observed to be 1-1.5 μm in size with interesting morphologies of various cross sections such as triangular, trapezoidal, pentagonal and hexagonal etc. having solid, hollow/semi-hollow appearances. The as-synthesized CMPMCS were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Room temperature photoluminescence (PL) spectrum for Cd metal microcrystals exhibited a prominent emission band at 365 along with a shoulder peak at 404 nm. The UV main emission band is ascribed to radiative recombination of the electrons in the s, p conduction band near the Fermi surface and holes in the d bands generated under xenon light excitation whereas shoulder peak may be owing to surface oxidation effects or induced defects. This study shows the potential of CMPMCs for applications in optical devices. Based on vapour-solid (VS) process, growth mechanism for the formation of CMPMCs is also proposed and discussed briefly.  相似文献   
39.
Wireless Sensor Network (WSN) is considered to be one of the fundamental technologies employed in the Internet of things (IoT); hence, enabling diverse applications for carrying out real-time observations. Robot navigation in such networks was the main motivation for the introduction of the concept of landmarks. A robot can identify its own location by sending signals to obtain the distances between itself and the landmarks. Considering networks to be a type of graph, this concept was redefined as metric dimension of a graph which is the minimum number of nodes needed to identify all the nodes of the graph. This idea was extended to the concept of edge metric dimension of a graph G, which is the minimum number of nodes needed in a graph to uniquely identify each edge of the network. Regular plane networks can be easily constructed by repeating regular polygons. This design is of extreme importance as it yields high overall performance; hence, it can be used in various networking and IoT domains. The honeycomb and the hexagonal networks are two such popular mesh-derived parallel networks. In this paper, it is proved that the minimum landmarks required for the honeycomb network HC(n), and the hexagonal network HX(n) are 3 and 6 respectively. The bounds for the landmarks required for the hex-derived network HDN1(n) are also proposed.  相似文献   
40.
A convenient and scalable technique for the synthesis of rutile titanium dioxide (TiO2) nano-rods was presented by using bulk TiO2 powder, sodium hydroxide (NaOH) and distilled water as raw materials. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) studies indicate that the prepared sample is crystalline and free from any impurities, however, it has no distinct shape and possesses a huge degree of agglomeration, and the average crystal size is around 40 nm. After annealing the sample at 600 °C for 2 h, it is observed through FESEM that nano-rods are formed. And XRD analysis shows that the nano-rods are single crystalline with distinct and smooth surfaces in different sizes with average length of about 1 µm and diameter of about 80 nm. Further UV-visible spectroscopy and Raman studies were conducted for the prepared sample and the band gap of the final product is found to be 3.40 eV.  相似文献   
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