252 research outputs found
Passivity and synchronization of coupled complex-valued memristive neural networks
The coupled complex-valued memristive neural networks (CCVMNNs) are investigated in this study. First, we analyze the passivity of the proposed network model by designing an appropriate controller and using certain inequalities as well as Lyapunov functional method, and provide a passivity condition for the considered CCVMNNs. In addition, a criterion for guaranteeing synchronization of this kind of network is established. Finally, the effectiveness and correctness of the acquired theoretical results are verified by a numerical example
Noninteractive Verifiable Outsourcing Algorithm for Bilinear Pairing with Improved Checkability
It is well known that the computation of bilinear pairing is the most expensive operation in pairing-based cryptography. In this paper, we propose a noninteractive verifiable outsourcing algorithm of bilinear pairing based on two servers in the one-malicious model. The outsourcer need not execute any expensive operation, such as scalar multiplication and modular exponentiation. Moreover, the outsourcer could detect any failure with a probability close to 1 if one of the servers misbehaves. Therefore, the proposed algorithm improves checkability and decreases communication cost compared with the previous ones. Finally, we utilize the proposed algorithm as a subroutine to achieve an anonymous identity-based encryption (AIBE) scheme with outsourced decryption and an identity-based signature (IBS) scheme with outsourced verification
Miamia maimai n. sp., a new Pennsylvanian stem-orthopteran insect, and a case study on the application of cladotypic nomenclature
A new stem-orthopteran insect assignable to the – traditional – genus and the – cladotypic-defined – taxon Miamia Dana, 1864 is described based on abundant material collected from the Xiaheyan locality (Ningxia, China; Early Pennsylvanian). Intra-specific wing venation variability in Miamia maimai n. sp. is appreciated based on wing pairs of single individuals, and on a complete series of conditions. Rare variants are reported. Details of head and leg morphology are documented: the new species possesses a five-segmented tarsus provided with paired claws and arolium, and labial palps with at least four segments, probably five. The nomenclatural section is conducted under the cladotypic nomenclatural procedure, but in a way largely consistent with the traditional usage. This experiment demonstrates that a combination composed of a "genus level-taxon" name previously associated with a definition and type material (e.g. Miamia), a specific epithet (e.g. maimai), and authorship information (e.g. Béthoux et al. 2012), with further mention to "Miamia maimai" or "M. maimai", provides a suitable reference to the species under all nomenclatural procedures, including the traditional one.doi:10.1002/mmng.20120000
The Social Media Industry: Where Is it Heading?
The social media industry has entered a new stage with intensifying competition and heightened uncertainty about future directions. The purpose of this paper is to provide analyses of the current challenges and to identify industry-wide trends that may offer a roadmap for the future. This study identified five major trends in the current social media industry: 1) content is king, and that content is moving to visual; 2) artificial intelligence is key to competitive advantage; 3) network effects still matter, but business model innovation can overcome that barrier; 4) the need to broaden revenue sources; and 5) the strive for the everything app. In this changing environment, social media companies need to adapt and innovate their business models proactively to stay ahead
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IL-17A produced by αβ T cells drives airway hyper-responsiveness in mice and enhances mouse and human airway smooth muscle contraction.
Emerging evidence suggests that the T helper 17 (T(H)17) subset of αβ T cells contributes to the development of allergic asthma. In this study, we found that mice lacking the αvβ8 integrin on dendritic cells did not generate T(H)17 cells in the lung and were protected from airway hyper-responsiveness in response to house dust mite and ovalbumin sensitization and challenge. Because loss of T(H)17 cells inhibited airway narrowing without any obvious effects on airway inflammation or epithelial morphology, we examined the direct effects of T(H)17 cytokines on mouse and human airway smooth muscle function. Interleukin-17A (IL-17A), but not IL-17F or IL-22, enhanced contractile force generation of airway smooth muscle through an IL-17 receptor A (IL-17RA)-IL-17RC, nuclear factor κ light-chain enhancer of activated B cells (NF-κB)-ras homolog gene family, member A (RhoA)-Rho-associated coiled-coil containing protein kinase 2 (ROCK2) signaling cascade. Mice lacking integrin αvβ8 on dendritic cells showed impaired activation of this pathway after ovalbumin sensitization and challenge, and the diminished contraction of the tracheal rings in these mice was reversed by IL-17A. These data indicate that the IL-17A produced by T(H)17 cells contributes to allergen-induced airway hyper-responsiveness through direct effects on airway smooth muscle
Bis{2,4-dibromo-6-[(2-phenylethyl)iminomethyl]phenolato-κ2 N,O}cobalt(II)
In the title complex, [Co(C15H12Br2NO)2], the CoII atom is four-coordinated by two N,O-bidentate chelate Schiff base ligands, displaying a flattened tetrahedral coordination environment. The CoII atom occupies a special position on a twofold rotation axis. In the crystal, molecules are linked via weak C—H⋯Br interactions
Protective Effect of Hydrogen on Sodium Iodate-Induced Age-Related Macular Degeneration in Mice
Oxidative stress is one of the main causes of AMD. Hydrogen has anti-oxidative stress and apoptotic effects on retinal injury. However, the effect of hydrogen on AMD is not clear. In this study, fundus radiography, OCT, and FFA demonstrated that HRW reduced the deposition of drusen-like structures in RPE layer, prevented retina from thinning and leakage of ocular fundus vasculature induced by NaIO3. ERG analysis confirmed that HRW effectively reversed the decrease of a-wave and b-wave amplitude in NaIO3-mice. Mechanistically, HRW greatly reduced the oxidative stress reaction through decreased MDA levels, increased SOD production, and decreased ROS content. The OGG1 expression was downregulated which is a marker of oxidative stress. Involvement of oxidative stress was confirmed using oxidative stress inhibitor ALCAR. Moreover, oxidative stress reaction was associated with expression of Sirt1 level and HRW significantly inhibited the downregulation of Sirt1 expression. This result was further confirmed with AICAR which restore Sirt1 expression and activity. In addition, NaIO3-induced retinal damage was related to apoptosis via caspase 8 and caspase 9, but not the caspase 3 pathways, which led to upregulation of Bax and p53, downregulation of Bcl-2, and increase in Jc-1-positive cells in mice. However, HRW effectively reversed these effects that apoptosis induced. These results suggest that HRW protects retinal functions against oxidative stress injury through inhibiting downregulation of Sirt1 and reducing retinal apoptosis. Therefore, we speculated that hydrogen administration is a promising treatment for AMD therapy
Novel manufacturing process of pneumococcal capsular polysaccharides using advanced sterilization methods
Pneumococcal disease is caused by Streptococcus pneumoniae, including pneumonia, meningitis and sepsis. Capsular polysaccharides (CPSs) have been shown as effective antigens to stimulate protective immunity against pneumococcal disease. A major step in the production of pneumococcal vaccines is to prepare CPSs that meet strict quality standards in immunogenicity and safety. The major impurities come from bacterial proteins, nucleic acids and cell wall polysaccharides. Traditionally, the impurity level of refined CPSs is reduced by optimization of purification process. In this study, we investigated new aeration strategy and advanced sterilization methods by formaldehyde or β-propiolactone (BPL) to increase the amount of soluble polysaccharide in fermentation supernatant and to prevent bacterial lysis during inactivation. Furthermore, we developed a simplified process for the CPS purification, which involves ultrafiltration and diafiltration, followed by acid and alcohol precipitation, and finally diafiltration and lyophilization to obtain pure polysaccharide. The CPSs prepared from formaldehyde and BPL sterilization contained significantly lower level of residual impurities compared to the refined CPSs obtained from traditional deoxycholate sterilization. Finally, we showed that this novel approach of CPS preparation can be scaled up for polysaccharide vaccine production
Humic acid production from the degradation of Yima coal by Cunninghamella elegans combined with Bacillus sp.
Biodegradation is one of the important ways for the clean and efficient utilization of coal. However, the effectiveness of degradation by the combination of fungi and bacteria has not been well understood. In the present study, the combined degradation of the Yima coal was tested. The coal samples were firstly oxidized with nitric acid, followed by cultured in the media of Cunninghamella elegans and Bacillus sp.. The absorbance of A450, pH and metallic element (Cr, As, Mn, Pb, Co, Ni, Cu, Zn, Mo) contents of the degradation solution were determined by UV-visible spectrophotometry, pH meter and inductively coupled plasma mass spectrometry, respectively. The humic acid was analyzed by element analyzer, Fourier transform infrared spectroscopy and gas chromatog-raphy-mass spectrometry. The results showed that the humic acid yields of C. elegans, Bacillus sp. and their mixture were 58.17%, 61.00% and 67.17%, respectively. The pH of the degradation solution of mixed strains was similar to that of the bacteria. The characteristic products of the bacteria degradation were detected in the humic acid samples derived from mixed strains, while the opposite was true for the fungi. It was suggested that the combination of the two strains enhanced the alkaline environment and improved the degradation rate of nitric acid-treated coal. The bacteria played a leading role in the degradation process. Metallic elements (Cr, As, Mn, Pb, Co, Ni, Cu, Zn, Mo) were transferred from coal to the degradation solution during the degradation process, and the contents of Cr, As, Pb, Ni, Cu and Mo were fitted with A450, the coefficient of determination (R2) were greater than 0.6. It indicated that the contents of these six metal elements in the degradation solution could represent the degradation rate. Chemically extracted humic acid and biologically extracted humic acid were rich in the active functional groups such as carboxyl, hydroxyl, carbonyl, long-chain fatty acids (C16, C18) and four pyrrole derivatives. The biologically extracted humic acid also contained fatty acids (C3, C4, C5, C13, C14, C15), of smaller molecular weight, as well as nitrogen-containing compounds such as two pyrrole derivatives and a furan. The contents of C and H elements in the biologically extracted humic acid were higher than that in the chemically extracted humic acid
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