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51.
Solar‐driven interfacial vaporization by localizing solar‐thermal energy conversion to the air–water interface has attracted tremendous attention due to its high conversion efficiency for water purification, desalination, energy generation, etc. However, ineffective integration of hybrid solar thermal devices and poor material compliance undermine extensive solar energy exploitation and practical outdoor use. Herein, a 3D organic bucky sponge that has a combination of desired chemical and physical properties, i.e., broadband light absorbing, heat insulative, and shape‐conforming abilities that render efficient photothermic vaporization and energy generation with improved operational durability is reported. The highly compressible and readily reconfigurable solar absorber sponge not only places less constraints on footprint and shape defined fabrication process but more importantly remarkably improves the solar‐to‐vapor conversion efficiency. Notably, synergetic coupling of solar‐steam and solar‐electricity technologies is realized without trade‐offs, highlighting the practical consideration toward more impactful solar heat exploitation. Such solar distillation and low‐grade heat‐to‐electricity generation functions can provide potential opportunities for fresh water and electricity supply in off‐grid or remote areas.  相似文献   
52.
DNA shuffling was carried out with two chitosanase genes belonging to glycoside hydrolase family eight from Bacillus cereus KNUC51 and B. cereus KNUC55. The shuffled products, YM18 and YM20, which showed higher activity than the parents at 40°C, were selected for further studies. The 50 kDa chitosanases were purified using affinity chromatography with glutathione-Sepharose 4B. In general, the specific activity of YM18 is enhanced 250% and that of YM20 is 350% compared to the parents. YM20 exhibits a shift of the optimal pH level from 5.5 to 6.5. DNA sequence analysis revealed that YM18 and YM20 contained 2 amino acid substitutions (I13T and A87V for YM18; K66R and N352S for YM20). We presumed that these amino acid substitutions increase the specific activity and change the property of the two variants. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
53.
The application of microorganisms in the field of construction material is rapidly increasing worldwide; however, almost all studies that were investigated were bacterial sources with mineral-producing activity and not with organic substances. The difference in the efficiency of using bacteria as an organic agent is that it could improve the durability of cement material. This study aimed to assess the use of biofilm-forming microorganisms as binding agents to increase the compressive strength of cement-sand material. We isolated 13 alkaliphilic biofilmforming bacteria (ABB) from a cement tetrapod block in the West Sea, Korea. Using 16S RNA sequence analysis, the ABB were partially identified as Bacillus algicola KNUC501 and Exiguobacterium marinum KNUC513. KNUC513 was selected for further study following analysis of pH and biofilm formation. Cement-sand mortar cubes containing KNUC513 exhibited greater compressive strength than mineral-forming bacteria (Sporosarcina pasteurii and Arthrobacter crystallopoietes KNUC403). To determine the biofilm effect, Dnase I was used to suppress the biofilm formation of KNUC513. Field emission scanning electron microscopy image revealed the direct involvement of organic-inorganic substance in cement-sand mortar.  相似文献   
54.
Equus caballus papillomavirus type 1 (EcPV-1) was isolated from a cutaneous papilloma, the most common neoplasm in horses. The complete EcPV-1 nucleotide sequence and genomic organization were determined. Phylogenetic analysis showed that EcPV-1 is a close-to-root papillomavirus, with only distant relationships to the fibropapillomaviruses and the benign cutaneous papillomaviruses. To produce EcPV-1 virus-like particles (VLPs), the EcPV-1 L1 major capsid protein was expressed in insect cells using a recombinant baculovirus vector. The self-assembled EcPV-1 VLPs were morphologically indistinguishable from wild type papillomavirus virions. Monoclonal antibodies were developed against intact and denatured EcPV-1 VLPs. When tested by ELISA, all monoclonal antibodies produced against intact (#18) and some against denatured EcPV-1 VLPs (#16) reacted with intact EcPV-1 VLPs only, demonstrating that the VLPs carry type-specific conformational as well as linear epitopes on their surface. Recombinant EcPV-1 VLPs offer the potential of a noninfectious vaccine to prevent and eradicate equine cutaneous papillomatosis.  相似文献   
55.
The compound 20-HETE is involved in numerous physiological functions, including blood pressure and platelet aggregation. Glucuronidation of 20-HETE by UDP-glucuronosyltransferases (UGTs) is thought to be a primary pathway of 20-HETE elimination in humans. The present study identified major UGT enzymes responsible for 20-HETE glucuronidation and investigated their genetic influence on the glucuronidation reaction using human livers (n = 44). Twelve recombinant UGTs were screened to identify major contributors to 20-HETE glucuronidation. Based on these results, UGT2B7, UGT1A9, and UGT1A3 exhibited as major contributors to 20-HETE glucuronidation. The Km values of 20-HETE glucuronidation by UGT1A3, UGT1A9, and UGT2B7 were 78.4, 22.2, and 14.8 μM, respectively, while Vmax values were 1.33, 1.78, and 1.62 nmol/min/mg protein, respectively. Protein expression levels and genetic variants of UGT1A3, UGT1A9, and UGT2B7 were analyzed in human livers using Western blotting and genotyping, respectively. Glucuronidation of 20-HETE was significantly correlated with the protein levels of UGT2B7 (r2 = 0.33, P < 0.001) and UGT1A9 (r2 = 0.31, P < 0.001), but not UGT1A3 (r2 = 0.02, P > 0.05). A correlation between genotype and 20-HETE glucuronidation revealed that UGT2B7 802C>T, UGT1A9 −118T9>T10, and UGT1A9 1399T>C significantly altered 20-HETE glucuronide formation (P < 0.05–0.001). Increased levels of 20-HETE comprise a risk factor for cardiovascular diseases, and the present data may increase our understanding of 20-HETE metabolism and cardiovascular complications.  相似文献   
56.
57.
In 1997, cutaneous papillomatosis caused by Florida manatee (Trichechus manatus latirostris [Tm]) papillomavirus 1 (TmPV1) was detected in seven captive manatees at the Homosassa Springs Wildlife State Park, Florida, USA, and, subsequently, in two wild manatees from the adjacent Homosassa River. Since then, papillomatosis has been reported in captive manatees housed in other locations, but not in wild animals. To determine TmPV1 antibody prevalence in captive and wild manatees sampled at various locations throughout Florida coastal regions, virus-like particles, composed of the L1 capsid protein of TmPV1, were generated with a baculovirus expression system and used to measure anti-TmPV1 antibodies in an enzyme-linked immunosorbent assay. Serologic analysis of 156 manatees revealed a TmPV1 antibody prevalence of 26.3%, with no significant difference between captive (n=39) and wild (n=117) manatees (28.2% and 25.6%, respectively). No antibody-positive wild animal showed PV-induced cutaneous lesions, whereas papillomatosis was observed in 72.7% of antibody-positive captive manatees. Our data indicate that Florida manatees living in the wild are naturally infected by TmPV1 but rarely show TmPV1-induced papillomatosis. Hence, it appears that the wild population would not be harmed in a case of contact with captive animals without visible lesions and productive infections, which could be thus released into the wild.  相似文献   
58.
59.
High‐grade gliomas are one of the most common brain tumors and notorious for poor prognosis due to their malignant nature. Gliomas have an extensive area of hypoxia, which is critical for glioma progression by inducing aggressiveness and activating the angiogenesis process in the tumor microenvironment. To resolve the factors responsible for the highly malignant nature of gliomas, we comprehensively profiled the U373MG glioma cell secretome—exosome and soluble fraction under hypoxic and normoxic conditions. A total of 239 proteins were identified from the exosome and soluble fractions. Vascular endothelial growth factor, stanniocalcin 1 (STC1) and stanniocalcin 2, and insulin‐like growth factor binding protein 3 and 6, enriched in the soluble fraction, and lysyl oxidase homolog 2 enriched in the exosomal fraction were identified as upregulated proteins by hypoxia based on a label‐free quantitative analysis. STCs and insulin‐like growth factor binding proteins, which were identified as secretory proteins under hypoxic conditions, were highly correlated with glioma grade in human patients by microarray analysis. An in vitro scratch wound assay revealed that STC1 and 2 have important functions in the induction of cell migration in a hypoxia‐dependent manner, suggesting that they are hypoxia‐dependent migration factors.  相似文献   
60.
This study investigated the antifungal effects of cement paste containing Paenibacillus polymyxa E681 against Aspergillus niger, a deleterious fungus commonly found in cement buildings and structures. To test the antifungal effects, cement paste containing P. polymyxa E681 was neutralized by CO2 gas, and the fungal growth inhibition was examined according to the clear zone around the cement specimen. In addition to the antifungal effects of the cement paste added with bacteria, calcium crystal precipitation of P. polymyxa E681 was examined by qualitative and quantitative analyses. The cement paste containing P. polymyxa E681 showed strong antifungal effects but fusA mutant (deficient in fusaricidin synthesis) showed no antifungal activity. Crack sealing of the cement paste treated with P. polymyxa E681 was captured by light microscope showed fungal growth inhibition and crack repairing in cement paste.  相似文献   
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