The coherent transmission technology using digital signal processing and advanced modulation formats, is bringing networks closer to the theoretical capacity limit of optical fibres, the Shannon limit. The in-phase/quadrature electro-optic modulator that encodes information on both the amplitude and the phase of light, is one of the underpinning devices for the coherent transmission technology. Ideally, such modulator should feature a low loss, low drive voltage, large bandwidth, low chirp and compact footprint. However, these requirements have been only met on separate occasions. Here, we demonstrate integrated thin-film lithium niobate in-phase/quadrature modulators that fulfil these requirements simultaneously. The presented devices exhibit greatly improved overall performance (half-wave voltage, bandwidth and optical loss) over traditional lithium niobate counterparts, and support modulation data rate up to 320 Gbit s −1. Our devices pave new routes for future highspeed, energy-efficient, and cost-effective communication networks.

Induction of effective cytotoxic T lymphocyte (CTL) and/or a specific antibody against conserved viral proteins may be essential to the development of a safe and effective severe acute respiratory syndrome coronavirus (SARS-Cov) vaccine. DNA vaccination represents a new strategy for induction of humoral and cellular immune response. To determine the ability of SARS-Cov nucleoprotein (N protein) to induce antiviral immunity, in this report, we established a stable C2C12 line expressing SARS-Cov N protein, which was used as a target for specific CTL assay. We also expressed recombinant N proteins in Escherichia coli and prepared N protein-specific polyclonal antibodies. C3H/He mice were immunized with N protein-expressible pcDN-fn vector by intramuscular injections. We found that the DNA vaccination induced both N protein-specific antibody and specific CTL activity to the target. When C3H/He mice were immunized by three separate injections, high antibody titre (1:3200-1:6400, average titre is 1:4580) and high CTL activity (67.4+/-8.4% (E:T = 25:1), 69.6+/-6.7% (E:T = 50:1) and 71.8+/-6.2% (E:T = 100:1)) were observed. In the case of two vaccine injections, CTL activity was also high (56.6+/-12.7% (E:T = 25:1), 57.4+/-11.7% (E:T = 50:1) and 63.0+/-6.3% (E:T = 100:1)) However, antibody titres were much lower (1:200-1:3200, average titre is 1:980). Our results suggest that SARS-Cov nucleocapsid gene might be a candidate gene for SARS DNA vaccination.

cTo design and discover new antimicrobial peptides (AMPs) with high levels of antimicrobial activity, a number of machinelearning methods and prediction methods have been developed. Here, we present a new prediction method that can identify novel AMPs that are highly similar in sequence to known peptides but offer improved antimicrobial activity along with lower host cytotoxicity. Using previously generated AMP amino acid substitution data, we developed an amino acid activity contribution matrix that contained an activity contribution value for each amino acid in each position of the model peptide. A series of AMPs were designed with this method. After evaluating the antimicrobial activities of these novel AMPs against both Gram-positive and Gram-negative bacterial strains, DP7 was chosen for further analysis. Compared to the parent peptide HH2, this novel AMP showed broad-spectrum, improved antimicrobial activity, and in a cytotoxicity assay it showed lower toxicity against human cells. The in vivo antimicrobial activity of DP7 was tested in a Staphylococcus aureus infection murine model. When inoculated and treated via intraperitoneal injection, DP7 reduced the bacterial load in the peritoneal lavage solution. Electron microscope imaging and the results indicated disruption of the S. aureus outer membrane by DP7. Our new prediction method can therefore be employed to identify AMPs possessing minor amino acid differences with improved antimicrobial activities, potentially increasing the therapeutic agents available to combat multidrug-resistant infections.A ntimicrobial peptides (AMPs) are produced by multicellular organisms to defend against microbial infections. Along with potent antimicrobial activity, many AMPs also have the ability to enhance immunity by functioning as immunomodulators (1-3). AMPs therefore have excellent therapeutic potential, especially in light of increased drug resistance to many conventional antibiotic therapies. A number of naturally occurring peptides and synthetic derivatives have been developed or are currently in development (2, 4-6). Although AMPs vary in length, amino acid composition, and structure, they share some similarities, such as electrical charge and amphipathicity (3, 7). To determine the characteristics that are important in antimicrobial activity, bioinformatic tools and prediction methods have been developed (8), all based to some extent on the sequence similarities between peptides (9-11).To optimize the antimicrobial activity of identified AMPs and to predict novel peptide sequences, we present a machine-learning method based on the concept of an antimicrobial activity contribution score for each amino acid. Here, we consider that each amino acid in a peptide sequence possesses a different level of importance for the biological activity of that peptide, and this is represented by an assigned score. By calculation of each amino acid's contribution score, we can predict the antimicrobial activity of an AMP.To verify our results, we tested some of our designed AMPs ...

This paper analyzes the impact of IRCA 1986, a U.S. amnesty, on immigrants' human capital development and labor market outcomes. Because of IRCA, the 1975-1981 arrivals were all legalized by 1990. However, many of the 1982-1986 arrivals remained illegal. Using the California Latino immigrants in Census 1990, I find that the 1975-81 arrivals on average outperform the 1982-86 arrivals in men's wage, women's labor force participation rate, and English-speaking ability. This finding is not a general trend of labor market conditions, because the analysis using refugees and U.S.-born Latinos, which are two comparison groups without legal status issue, indicate no difference in outcomes between pre-1982 and post-1982 cohorts.

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