Electro-optic resonant phase modulator

An electro-optic resonant cavity is used to achieve phase modulation with lower driving voltages. Laser damage thresholds are inherently higher than with previously used integrated optics due to the utilization of bulk optics. Phase modulation is achieved at higher speeds with lower driving voltages than previously obtained with non-resonant electro-optic phase modulators. The instant scheme uses a data locking dither approach as opposed to the conventional sinusoidal locking schemes. In accordance with a disclosed embodiment, a resonant cavity modulator has been designed to operate at a data rate in excess of 100 megabits per sec. By carefully choosing the cavity finesse and its dimension, it is possible to control the pulse switching time to within 4 nano-sec. and to limit the required switching voltage to within 10 V. This cavity locking scheme can be applied by using only the random data sequence, and without the need of dithering of the cavity. Compared to waveguide modulators, the resonant cavity has a comparable modulating voltage requirement. Because of its bulk geometry, the resonant cavity modulator has the potential of accommodating higher throughput power. Mode matching into the bulk device is easier and typically can be achieved with higher efficiency. An additional control loop is incorporated into the modulator to maintain the cavity on resonance

Communicative Action and Citizen Journalism: A Case Study of \u3cem\u3eOhmyNews\u3c/em\u3e in South Korea

Drawing on Habermas’s theory of communicative action, this case study of OhmyNews in South Korea examines how citizen journalism operates in a broad organizational and social context. Through in-depth interviews with professional and citizen journalists, the study reveals that citizen journalism can be well understood at the intersection between the lifeworld and systems. Specifically, the study finds a coexistence mechanism by which citizen journalism competes, collaborates, coordinates, and compromises with professional journalism through communicative action, such as mutual understanding, reason-based discussion, and consensus building

Distribution of News Information through Social Bookmarking: An Examination of Shared Stories in the \u3cem\u3eDelicious\u3c/em\u3e Website

Introduction. This study examined the selection and sharing of news stories from Delicious, a popular social bookmarking site, in order to identify the most frequently consulted news information sources and news topics. Method. Targeting US-specific sources through initial computer screening of URLs, we employed content analysis to further analyse story topics and sources that were unclassified through the initial computer screening method. Analysis. After examining frequencies and percentages of the variables, a qualitative analysis was employed to assess relationships between story sources and story topics. Results. Findings document the diverse nature of stories from both traditional and new media channels. Social media sources, primarily blogs, are growing as a major news source. Prominent traditional news media were not exclusively used, and the sheer volume of uncategorized pages suggests that online news seekers consider alternative Web pages encountered during casual navigation as news sources. Conclusions. What online news audiences consider to be news is becoming increasingly broad and complex with unclassified sources dominating tagged stories. New information sources appear to make up for deficient story topics in the mainstream media

Anatomy of Front Pages: Comparison Between \u3cem\u3eThe New York Times\u3c/em\u3e and Other U.S. Major Metropolitan Newspapers

Using content analysis, this article compares the front-page elements of The New York Times with six major metropolitan national newspapers to assess how different news organizations package and present their most important page to the public. Findings reveal that The New York Times featured more international and national news stories, depended more frequently on its own staff for both stories and images, and used smaller headlines on its front pages compared with the other major metropolitan newspapers

U.S. Newspaper Editors’ Ratings of Social Media as Influential News Sources

Social media, as one key platform for citizen journalism, are becoming a useful news-gathering tool for journalists. Based on data from a nationwide probability sample of newspaper editors in the United States, this study investigates the extent to which newspaper editors consider social media an influential news source. Results show that variations in editors’ ratings of social media as a news source were related to multiple levels of influence, including professional journalistic experience, organization size, community structural pluralism, and citizen journalism credibility. Implications are discussed for the roles of social media in news production

Electric-optic resonant phase modulator

An electro-optic resonant cavity is used to achieve phase modulation with lower driving voltages. Laser damage thresholds are inherently higher than with previously used integrated optics due to the utilization of bulk optics. Phase modulation is achieved at higher speeds with lower driving voltages than previously obtained with non-resonant electro-optic phase modulators. The instant scheme uses a data locking dither approach as opposed to the conventional sinusoidal locking schemes. In accordance with a disclosed embodiment, a resonant cavity modulator has been designed to operate at a data rate in excess of 100 Mbps. By carefully choosing the cavity finesse and its dimension, it is possible to control the pulse switching time to within 4 ns and to limit the required switching voltage to within 10 V. Experimentally, the resonant cavity can be maintained on resonance with respect to the input laser signal by monitoring the fluctuation of output intensity as the cavity is switched. This cavity locking scheme can be applied by using only the random data sequence, and without the need of additional dithering of the cavity. Compared to waveguide modulators, the resonant cavity has a comparable modulating voltage requirement. Because of its bulk geometry, resonant cavity modulator has the potential of accommodating higher throughput power. Furthermore, mode matching into a bulk device is easier and typically can be achieved with higher efficiency. On the other hand, unlike waveguide modulators which are essentially traveling wave devices, the resonant cavity modulator requires that the cavity be maintained in resonance with respect to the incoming laser signal. An additional control loop is incorporated into the modulator to maintain the cavity on resonance

R992C (p.R1192C) Substitution in collagen II alters the structure of mutant molecules and induces the unfolded protein response.

We investigated the molecular bases of spondyloepiphyseal dysplasia (SED) associated with the R992C (p.R1192C) substitution in collagen II. At the protein level, we analyzed the structure and integrity of mutant molecules, and at the cellular level, we specifically studied the effects of the presence of the R992C collagen II on the biological processes taking place in host cells. Our studies demonstrated that mutant collagen II molecules were characterized by altered electrophoretic mobility, relatively low thermostability, the presence of atypical disulfide bonds, and slow rates of secretion into the extracellular space. Analyses of cellular responses to the presence of the mutant molecules showed that excessive accumulation of thermolabile collagen II was associated with the activation of an unfolded protein response and an increase in apoptosis of host cells. Collectively, these data suggest that molecular mechanisms of SED may be driven not only by structural changes in the architecture of extracellular collagenous matrices, but also by intracellular processes activated by the presence of mutant collagen II molecules

Decision‐Making About Reproductive Choices Among Individuals At‐Risk for Huntington's Disease

We explored how individuals at‐risk for HD who have or have not been tested make reproductive decisions and what factors are involved. We interviewed 21 individuals (8 with and 4 without the mutation, and 9 un‐tested) in‐depth for 2 hours each. At‐risk individuals faced a difficult series of dilemmas of whether to: get pregnant and deliver, have fetal testing, have pre‐implantation genetic diagnosis, adopt, or have no children. These individuals weighed competing desires and concerns: their own desires vs. those of spouses vs. broader moral concerns (e.g., to end the disease; and/or follow dictates against abortion) vs. perceptions of the interests of current or future offspring. Quandaries arose of how much and to whom to feel responsible. Some changed their perspectives over time (e.g., first “gambling,” then being more cautious). These data have critical implications for genetic counselors and other health care workers and future research, particularly as more genetic tests become available

Atypical Clinical and Diagnostic Features in Ménétrier's Disease in a Child

Ménétrier's disease is one of the rarest protein-losing gastropathies in childhood. It is characterized clinically by non-specific gastrointestinal symptoms and edema, biochemically by hypoalbuminemia, and pathologically by enlarged gastric folds. In adults, this disease can be devastating with significant morbidity and mortality. In childhood, it is a self-limiting, transient and benign illness. Its treatment is largely supportive with total parenteral nutrition (TPN) while oral intake is encouraged. Acute onset of vomiting in healthy school age children can be initially explained by acute viral gastroenteritis. However, persistent vomiting associated with hematemesis and severe abdominal pain should warrant further work-up. This case report illustrates a self-limiting and rare cause of protein-losing enteropathy called Ménétrier's disease that presented with several variant clinical features not typically described in association with this entity

Disclosures of Huntington disease risk within families: Patterns of decision‐making and implications

Patterns of disclosure of Huntington disease risk and genetic test results among family members are important, but have been underexplored. We interviewed 21 individuals in‐depth—eight mutation‐positive for HD, four mutation‐negative, and nine not tested—for 2 hr each. Within families, critical questions arose of what, when, and to whom to disclose, and what to do post‐disclosure. Interviewees wrestled with dilemmas of what to tell (e.g., suspicions vs. confirmed symptoms; initiation vs. completion of testing; partial vs. indirect information), how to disclose (e.g., planning in advance vs. “blurting out” information in arguments), and whether and how to tell extended family members. Questions arose of when to tell (i.e., to avoid disclosing “too early” or “too late”). Similarities and differences emerged related to types of relationships (e.g., parents telling offspring vs. offspring telling parents vs. siblings telling each other). Individuals often disclosed because of perceived duty to foster the health of their family members, enabling these others to pursue appropriate medical evaluation, if desired. Yet tensions arose because the information could burden these members, who also have rights to remain “in denial” if they wish and not discuss the topic or pursue testing. Post‐disclosure, dilemmas emerged of whether and how much to encourage family members to pursue testing. These data shed important light on critical issues that have received little, if any, attention concerning what, how, and when disclosure occurs, and have key implications for at‐risk individuals, genetic counselors, and other health care workers (HCWs), and for future research. At‐risk individuals would benefit from considering these issues in advance. HCWs need to realize that these decisions are multi‐faceted. Future research can explore whether, when, how, and how often HCWs raise these issues with individuals