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Streptococcus pneumoniae remains a leading cause of bacterial pneumonia despite the widespread introduction of vaccines for disease prevention. While vaccines have been effective at reducing the incidence of most vaccine-included serotypes, a rise in infection due to non-vaccine serotypes, and moderate efficacy against some vaccine included serotypes have contributed to high disease incidence, particularly in the elderly. Additionally, numerous isolates of S. pneumoniae are antibiotic resistant or multi-drug resistant. Several highly conserved pneumococcal proteins that are prevalent in the majority of serotypes have been examined and tested as potential vaccines in preclinical and clinical trials. We isolated the first human monoclonal antibodies (mAbs) (PhtD3, PhtD6, PhtD7, PhtD8, PspA16) against the pneumococcal histidine triad protein (PhtD), and the pneumococcal surface protein A (PspA), two conserved and protective antigens. mAbs to PhtD target diverse epitopes spanning the entire PhtD protein, and mAb PspA16 targets the N-terminal segment of PspA. The PhtD-specific mAbs were found to bind to multiple serotypes, while PspA16 serotype breadth was limited. In addition, we examined the prophylactic and therapeutic efficacy of mAb PhtD3 in several mouse models of pneumococcal pneumonia and sepsis. mAb PhtD3 prolonged the survival of infected mice when administered 2 hours before infection or 24 hours after infection. Additionally, mAb PhtD3 was effective against pneumococcal serotypes 4 and 3, the latter of which is a leading cause of invasive pneumococcal disease. Overall, our results provide new therapeutic reagents for disease prevention, and identify regions on PhtD and PspA recognized by human B cells.

Keeping abreast of trends in the articles and rapidly grasping a body of article’s key points and relationship from a holistic perspective is a new challenge in both literature research and text mining. As the important component, keywords can present the core idea of the academic article. Usually, articles on a single theme or area could share one or some same keywords, and we can analyze topological features and evolution of the articles co-keyword networks and keywords co-occurrence networks to realize the in-depth analysis of the articles. This paper seeks to integrate statistics, text mining, complex networks and visualization to analyze all of the academic articles on one given theme, complex network(s). All 5944 “complex networks” articles that were published between 1990 and 2013 and are available on the Web of Science are extracted. Based on the two-mode affiliation network theory, a new frontier of complex networks, we constructed two different networks, one taking the articles as nodes, the co-keyword relationships as edges and the quantity of co-keywords as the weight to construct articles co-keyword network, and another taking the articles’ keywords as nodes, the co-occurrence relationships as edges and the quantity of simultaneous co-occurrences as the weight to construct keyword co-occurrence network. An integrated method for analyzing the topological features and evolution of the articles co-keyword network and keywords co-occurrence networks is proposed, and we also defined a new function to measure the innovation coefficient of the articles in annual level. This paper provides a useful tool and process for successfully achieving in-depth analysis and rapid understanding of the trends and relationships of articles in a holistic perspective.

A new and efficient approach for the synthesis of oxygen and nitrogen heterocycles by organoselenium catalysis has been developed. The exo-cyclization proceeded smoothly under mild conditions with good functional group tolerance and excellent regioselectivity. Mechanistic studies revealed that 1-fluoropyridinium triflate is key for oxidative cyclization.

Listed energy companies play an important role in both the energy financial market and energy commodity market. As owners of listed energy companies, shareholders can influence the stability of the energy stock market by increasing or decreasing their holdings. To analyze the evolutionary features and stability of shareholders’ co-holding behavior, we constructed a derivative holding-based structural equivalence network of the shareholders (holding-based network) based on the primitive shareholding network of the listed companies and their shareholders. The main data used in this paper are the semi-annual reports from 2003 to 2012 that contain information about Chinese listed energy companies’ top 10 shareholders. The holding-based network takes the shareholders as nodes, whether holding the same listed energy companies’ stock at the same time as the edges, and the number of listed energy companies co-held as the weights. Due to the unique topological features of the holding-based network, we improved the Heuristic Algorithm to find the associated maximal connected sub-graph of the network, which is the main group of shareholders with shareholding consistency of the listed energy companies. This paper creates a new approach to analyze the relationships in the energy stock market, presenting a new method to analyze shareholder behavior.

The function of plant polyphenols in controlling body weight has been in focus for a long time. The aim of this study was to investigate the effect of plant polyphenols on fecal microbiota utilizing oligosaccharides. Three plant polyphenols, quercetin, catechin and puerarin, were added into liquid media for fermenting for 24 h. The pH values, OD600 of the cultures and the content of carbohydrates at 0, 6, 10, 14, 18 and 24 h were determined. The abundance of Bacteroidetes and Firmicutes in each culture was quantified with qPCR after 10 h of fermentation, and the bacterial composition was analyzed using the software Quantitative Insights Into Microbial Ecology. The results revealed that all three plant polyphenols could significantly inhibit the growth of Bacteroidetes (P < 0.01) and Firmicutes (P < 0.01) while at the same time down-regulate the ratio of Bacteroidetes to Firmicutes (P < 0.01). But the fecal bacteria could maintain the ability to hydrolyze fructo-oligosaccharide (FOS) in vitro. Among the tested polyphenols, catechin presented the most intense inhibitory activity towards the growth of Bacteroidetes and Firmicutes, and quercetin was the second. Only the samples with catechin had a significantly lower energy metabolism (P < 0.05). In conclusion, plant polyphenols can change the pathway of degrading FOS or even energy metabolism in vivo by altering gut microbiota composition. It may be one of the mechanisms in which plant polyphenols can lead to body weight loss. It's the first report to study in vitro gastrointestinal microbiota fermenting dietary fibers under the intervention of plant polyphenols.

Compared to organic solar cells based on narrow-bandgap nonfullerene small-molecule acceptors, the performance of all-polymer solar cells (all-PSCs) lags much behind due to the lack of high-performance n-type polymers, which should have low-aligned frontier molecular orbital levels and narrow bandgap with broad and intense absorption extended to the near-infrared region. Herein, two novel polymer acceptors, DCNBT-TPC and DCNBT-TPIC, are synthesized with ultranarrow bandgaps (ultra-NBG) of 1.38 and 1.28 eV, respectively. When applied in transistors, both polymers show efficient charge transport with a highest electron mobility of 1.72 cm2 V-1 s-1 obtained for DCNBT-TPC. Blended with a polymer donor, PBDTTT-E-T, the resultant all-PSCs based on DCNBT-TPC and DCNBT-TPIC achieve remarkable power conversion efficiencies (PCEs) of 9.26% and 10.22% with short-circuit currents up to 19.44 and 22.52 mA cm-2 , respectively. This is the first example that a PCE of over 10% can be achieved using ultra-NBG polymer acceptors with a photoresponse reaching 950 nm in all-PSCs. These results demonstrate that ultra-NBG polymer acceptors, in line with nonfullerene small-molecule acceptors, are also available as a highly promising class of electron acceptors for maximizing device performance in all-PSCs.

Enterotoxigenic Escherichia coli (ETEC) strains producing heat-labile toxin (LT) and/or heat-stable toxin (STa) are a top cause of children's diarrhea and travelers' diarrhea. Holotoxin-structured GM1-binding LT is a strong immunogen and an effective adjuvant, and can serve a carrier or a platform for multivalent vaccine development. However, the significance of peptide domains or epitopes of LT particularly enzymatic LTA subunit in association with LT enterotoxicity and immunogenicity has not been characterized. In this study, we identified B-cell epitopes in silico from LTA subunit and examined epitopes for immunogenicity and association with LT enterotoxicity. Epitopes identified from LTA subunit were individually fused to a modified chicken ovalbumin carrier protein, and each epitope-ovalbumin fusion was used to immunize mice. Data showed all 11 LTA epitopes were immunogenic; epitope 7 (105SPHPYEQEVSA115) induced greater titers of anti-LT antibodies which neutralized LT enterotoxicity more effectively. To examine these epitopes for the significance in LT enterotoxicity, we constructed LT mutants by substituting each of 10 epitopes at the toxic A1 domain of LTA subunit with a foreign epitope and examined LT mutants for enterotoxicity and GM1-binding activity. Data showed that LT mutants exhibited no enterotoxicity but retained GM1-binding activity. The results from this study indicated that while not all immunodominant LTA epitopes were neutralizing, LT mutants with an individual epitope substituted lost enterotoxicity but retained GM1-binding activity. These results provided additional information to understand LT immunogenicity and enterotoxicity and suggested the potential application of LT platform for multivalent vaccines against ETEC diarrhea and other diseases.IMPORTANCE No vaccine is licensed for enterotoxigenic Escherichia coli (ETEC) strains, which remain a leading cause of diarrhea in children from developing countries and international travelers. GM1-binding heat-labile toxin (LT) which is a key virulence factor of ETEC diarrhea is a strong vaccine antigen and a self-adjuvant. LT can also serve a backbone or platform for MEFA (multiepitope fusion antigen), a newly developed structural vaccinology technology, to present heterogeneous epitopes (by replacing LT epitopes) and to mimic epitope antigenicity for development of broadly protective vaccines. Data from this study identified neutralizing LT epitopes and demonstrated that substitution of LT epitopes eliminated LT enterotoxicity without altering GM1-binding activity, suggesting LT is potentially a versatile MEFA platform to present heterogeneous epitopes for multivalent vaccines against ETEC and other pathogens.

Scalable extension to the H.264/AVC video compression standard (SVC) enables one or more subset bit streams (layers) with multiple qualities to be contained in one high-quality video bit stream, which is a good solution for simultaneous transmission of video programs with different qualities. To fulfill the target of scalable video broadcasting (SVB), the transmission of SVC in broadcasting system uses the physical layer sub-channel technique, and different layers are transmitted in different sub-channels. Bit division multiplexing (BDM) is a newly proposed physical layer sub-channel technique at bit level, which could achieve higher transmission efficiency than conventional time division multiplexing scheme and improve the flexibility of the broadcasting system in conventional hierarchical modulation. In this paper, the combination of SVC and BDM technique is proposed and implemented for SVB. In addition, simplified BDM scheme, BDM-Lite, is also investigated for SVB, which significantly decreases the demapping complexity of the baseline layer due to high-order modulation, which is highly desirable for mobile/handheld receivers. Both simulation and FPGA implementation results show that the proposed BDM-Lite scheme has the advantages of both high transmission efficiency and low complexity of baseline reception.

We report a novel small molecule acceptor (SMA) named FTTB-PDI4 obtained via ring-fusion between the thiophene and perylene diimide (PDI) units of a PDI-tetramer with a tetrathienylbezene (TTB) core. A small voltage loss of 0.53 V and a high power conversion efficiency of 10.58% were achieved, which is the highest value reported for PDI-based devices to date. By comparing the fused and nonfused SMAs, we show that the ring-fusion introduces several beneficial effects on the properties and performances of the acceptor material, including more favorable energy levels, enhanced light absorption and stronger intermolecular packing. Interestingly, morphology data reveal that the fused molecule yields higher domain purity and thus can better maintain its molecular packing and electron mobility in the blend. Theoretical calculations also demonstrate that FTTB-PDI4 exhibits a "double-decker" geometry with two pairs of mostly parallel PDI units, which is distinctively different from reported PDI-tetramers with highly twisted geometries and can explain the better performance of the material. This work highlights the promising design of PDI-based acceptors by the ring-fusion strategy.

Heat-stable toxin (STa)-producing enterotoxigenic Escherichia coli (ETEC) strains are a top cause of moderate-to-severe diarrhea in children from developing countries and a common cause of travelers' diarrhea. Recent progress in using STa toxoids and toxoid fusions to induce neutralizing anti-STa antibodies has accelerated ETEC vaccine development. However, concern remains regarding whether the derived anti-STa antibodies cross-react with STa-like guanylin and uroguanylin, two guanylate cyclase C (GC-C) ligands regulating fluid and electrolyte transportation in human intestinal and renal epithelial cells. To further divert STa from guanylin and uroguanylin structurally and antigenically and to eliminate anti-STa antibody cross-reactivity with guanylin and uroguanylin, we mutated STa at the 9th (leucine), 12th (asparagine), and 14th (alanine) residues for the double and triple mutants STa L9A/N12S , STa L9A/A14H , STa N12S/A14T , and STa L9A/N12S/A14H . We then fused each STa mutant (three copies) to a monomeric heat-labile toxin (LT) mutant (mnLT R192G/L211A ) for the toxoid fusions 3×STa L9A/N12S -mnLT R192G/L211A , 3×STa L9A/A14H -mnLT R192G/L211A , 3×STa N12S/A14T -mnLT R192G/L211A , and 3×STa L9A/N12S/A14H -mnLT R192G/L211A ; examined each fusion for anti-STa immunogenicity; and assessed the derived antibodies for in vitro neutralization activity against STa toxicity and for cross-reactivity with guanylin and uroguanylin. Mice subcutaneously immunized with each fusion protein developed anti-STa antibodies, and the antibodies derived from 3×STa N12S -mnLT R192G/L211A , 3×STa L9A/N12S -mnLT R192G/L211A , or 3×STa N12S/A14T -mnLT R192G/L211A prevented STa from the stimulation of intracellular cGMP in T-84 cells. Competitive enzyme-linked immunosorbent assays (ELISAs) showed that guanylin and uroguanylin hardly blocked the binding of anti-STa antibodies to the coated STa-ovalbumin conjugate. These results indicated that antibodies derived from 3×STa N12S -mnLT R192G/L211A , 3×STa L9A/N12S -mnLT R192G/L211A , or 3×STa N12S/A14T -mnLT R192G/L211A neutralized STa and had little cross-reactivity with guanylin and uroguanylin, suggesting that these toxoid fusions are suitable antigens for ETEC vaccines. IMPORTANCE Enterotoxigenic Escherichia coli (ETEC) strains are a leading cause of children's diarrhea and travelers' diarrhea. Currently, there is no licensed vaccine against ETEC diarrhea. One key challenge is to identify safe antigens to induce antibodies neutralizing the key STa without cross-reacting with guanylin and uroguanylin, two important ligands controlling homeostasis in human intestinal and renal epithelial cells. In this study, we generated nontoxic fusion antigens that induced antibodies that neutralize STa enterotoxicity in vitro and do not cross-react with guanylin or uroguanylin. These fusions have become the preferred antigens for the development of ETEC vaccines to potentially prevent the deaths of hundreds of thousands of young children and hundreds of millions of diarrheal cases each year.

Shareholders are the owners of listed companies, and their relationships can directly affect the structure of the stock market. In this paper, we analyze the topological properties and evolution of the cross-shareholding networks of listed companies in the past 5 years in China from 2007 to 2011, an infrequently considered topic, by taking shareholders’ cross-shareholding relationships into account. This analysis arrives at a deeper insight into the inner characteristics of China’s stock market. We find that the cross-shareholding networks of listed companies with shareholders’ cross-shareholding relationships display statistical features that reveal the stock market’s complex relationships more precisely. In particular, the results show that when the shareholders’ cross-shareholding relationships are considered, first, the In-degree and Out-degree of the cross-shareholding networks follow power-law distribution and the R 2 of the linear regression analysis of the cumulative degree distribution is relatively higher; second, the modularity of the communities is larger; finally, both the number of members of top-ranked communities and the number of communities that have a large number of members are larger than those of which only considering the relationships between shareholders and listed companies are taken into account. Such cross-shareholding networks analysis taking shareholders’ cross-shareholding relations into account would be a helpful tool for supervisory departments and for stock market researchers to grasp the inner cross-shareholding relationships of listed companies in China, and it will be also helpful for the further researches about the “agent problems” in the stock markets from a whole point of view.

Listed energy company is the principal part of the energy market, including the energy investment, energy trade, energy operation etc. Stockholders are the owners of the listed energy companies, whose relationships would affect the stability of the energy market directly. In order to analyze the evolution features and stability of the relationships between the stockholders, we constructed a generator holding-based structural equivalence network of the shareholders based on the primitive affiliation network of the listed companies and their shareholders. The main data used in this paper is the semi-annual reports from 2003 to 2012 which contain the information about Chinese listed energy companies’ top 10 shareholders. The holding-based network takes the shareholders as the nodes, whether holding the same listed energy companies’ stock at the same period as the edges, and the number of the listed energy companies holding at the same time as the weights. In this paper, we improved the traditional Heuristic method and then found the maximal connected sub-graphs of the holding-based networks in different time domain by the improved Heuristic method. The main method and theory used in this paper is complex network, we calculated and analyzed the evolution and the stability of the maximal connected sub-graphs. This paper comes up with a new angle to analyze the relationships in the energy stock market, and present a new method to analyze the stockholders’ behaviors.

Conventional organic solar cell (OSC) systems have significant energy offsets between the donor and acceptor both at the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. Because of this, in a bulk heterojunction (BHJ) system, electrons typically transport in acceptors, whereas holes typically transport in donors. It is not favorable for electrons to hop back and forth between the donor and acceptor because the hopping is energetically disfavored. In such conventional OSC systems, the addition of donor polymer to acceptor films should typically reduce the electron mobility. In this study, a surprisingly large increase (up to 30×) in electron mobility is observed in an OSC blend when introducing a polymer donor into small molecular acceptor. By ruling out morphology reasons, it is shown that the donor polymer can assist the electron transport by providing "bridges" or a "shortcut" for electron transport across the domains of small molecular acceptors. This can happen because, for these systems, the LUMO offset is small. The study shows the benefits of donor-assisted electron transport in BHJ systems with small energetic offsets. This finding could be also applied to other fields to tune the optimized charge transport property of organic materials or slush blends.

A new and efficient approach for the synthesis of oxygen and nitrogen heterocycles by organoselenium catalysis has been developed. The exo-cyclization proceeded smoothly under mild conditions with good functional group tolerance and excellent regioselectivity. Mechanistic studies revealed that 1-fluoropyridinium triflate is key for oxidative cyclization.

Scalable video transmission (SVT) system, which is able to transmit video programs with multiple qualities to different users with different channel and reception conditions, is well designed and implemented on FPGA in this paper. The designed SVT system is based on bit division multiplexing (BDM) technique and H.264/SVC. Capacity region analysis, bit error ratio (BER) simulations and field trial are performed in this paper. The results show that the proposed SVT system has higher spectrum efficiency than the traditional SVT system with redundant source bit streams and time division multiplexing technique. Field trial results show that, with the proposed SVT system, video services with different qualities have different coverage areas.

Haemophilus parasuis is generally considered a commensal organism in the upper respiratory tract of pigs, where it evades the host immune system and survives the challenging host environment. In response to various host stresses, H. parasuis strains can adapt to the adverse conditions. However, the specific bacterial factors that participate in this process are poorly understood. Here, we investigated the role of ClpP in H. parasuis virulent strain CF7066 by generating a clpP deletion mutant (ΔclpP), as well as a complemented strain C-clpP. Our findings supported that ClpP is essential for stress tolerance of H. parasuis, by the demonstrations that the ΔclpP mutant showed decreased resistance to heat, oxidation, and osmotic pressure. Notably, we observed increased autoagglutination and biofilm formation in the ΔclpP mutant and the amount of polysaccharides and extracellular proteins, which are the main components of biofilm, were much higher in the ΔclpP mutant than the wild-type strain. Real-time PCR demonstrated that the transcriptional regulators csrA and rpoD, and a possible biofilm repressor luxS were significantly downregulated upon clpP deletion. Together, these observations suggest that ClpP plays an essential role in stress tolerance, and negatively regulates biofilm formation in H. parasuis.

This paper proposes an adaptive normalized min-sum algorithm for the decoding of low-density parity check (LDPC) codes, which utilizes an adaptive normalization factor to improve the accuracy of the soft information transferred during the iterative decoding process, and provides superior performance accordingly. This adaptive normalization factor can be adjusted dynamically and adaptively at each decoding iteration according to a look-up table obtained via training and simulation. Its implementation facility and independence from the channel characteristics make the proposed adaptive normalized min-sum algorithm expect a wide application. Simulation results show that the proposed algorithm can achieve performance much closer to the sum-product algorithm and a coding gain of around 0.2dB compared to the conventional normalized min-sum algorithm for DVB-S2's rate 2/5 and 3/5 LDPC codes over the additive white Gaussian noise (AWGN) channel.

Amplitude phase shift keying (APSK) constellation with Gray mapping was proposed recently. In this paper, a simplified soft demapping algorithm for Gray-APSK is developed. Simulation results show that the proposed algorithm decreases the soft demapping complexity considerably with little loss of SNR.

Summary form only given. The recent demonstration of emission spectral narrowing in /spl pi/-conjugated polymer films, has stirred widespread interest to the phenomenon of laser-action in these materials. It is now generally believed that spectral narrowing in superior polymer films is caused by amplified spontaneous emission (i.e. single pars stimulated emission (SE)) enhanced by the optical waveguiding in the film. However, the femtosecond exciton dynamics under SE conditions, and the effects of exciton inhomogeneity in the films on the properties of the SE and its dynamics have not been investigated. In this study we have used the gated frequency up-conversion technique with 300 fs time resolution to fully resolve the emission dynamics in thin films of 2,5-dioctyloxy poly(p-phenylene vinylene) (DOO-PPV) an excitation power, below and above the threshold power for spectral narrowing.