A preliminary study of flat-panel displays

Six display technologies that might be of future value in a spacelab workstation are discussed. Some have been developed to the point where they could be used as a computer display while others have not. The display technologies studied are electroluminescents, light-emitting didodes, gas plasma, liquid crystal, electrochromic, and electrophoretic. An explanation of each mechanism is provided along with the state-of-the-art development

Cyber Security: China and Russia\u27s Erosion of 21st Century United States\u27 Hegemony

With Russia and China emerging as challengers to U.S. hegemony, the use of cyber warfare could tilt the current balance of power in either of their favors. Using various methods, hackers can acquire sensitive information and destroy online infrastructures. In the development of cyber warfare, China has become a seasoned veteran with computer virus operations dating back to 199714. Russia has emerged as a cyber aggressor, as seen in Russia’s cyber attacks on several countries in the last decade. This paper argues that, with the growth of foreign cyber technology, the probability of cyberspace being used as a military front by state or non-state actors against the United States increases

Ethical Issues Associated With Routine Screening and Prophylaxis for Group B Streptococcus in Pregnancy

An increased awareness of the impact of group B streptococcus (GBS) infection on neonatal outcome has prompted several seemingly discordant committee recommendations. Intrapartum antibiotics are effective in reducing the risk of neonatal morbidity when administered to a colonized woman who has a clinical condition that places her neonate at high risk for early-onset sepsis. However, less is known about the efficacy of prophylactic antibiotics in the colonized woman who does not have obvious risk factors. Some authorities have suggested that providers refrain from administering intrapartum antibiotics to colonized women who do not have any of these risk factors, primarily due to concerns about potential adverse reactions, selection of resistant pathogens, and cost-effectiveness. These recommendations may conflict with the desires of an informed woman who weighs the real, albeit low, risk for serious neonatal disease against the lower perceived risk of adverse maternal sequelae from allergic reactions to the antimicrobial agents. Selective prophylaxis for GBS disease that is limited to the colonized parturient with risk factors has the potential for creating conflict because maternal beneficence-based obligations of the physician may be at odds with maternal autonomy-based obligations. We believe that, given all currently available information, providers have a moral obligation to discuss GBS screening and treatment issues with patients. The potential for conflict between patient and physician at the time of delivery can be minimized through the use of preventive ethics, allowing patients to develop advance directives regarding intrapartum management within the confines of reasonable and cost-effective care. Until a consensus is reached among experts, the most prudent approach would be to address such issues proactively and individualize care based upon the overall estimation and anticipation of risk as well as the patient's specific desires

Process Evaluation of the Los Angeles Unified School District Nutrition Network

IntroductionThis study evaluated the Los Angeles Unified School District Nutrition Network, a large multicomponent nutrition and physical activity program in an ethnically diverse school district, launched in 2000.MethodsWe calculated descriptive statistics and performed hierarchical logistic regression on school-level demographic and implementation data.ResultsThirty-six percent of eligible schools participated in 2001, and 79% of participating schools reapplied the following year. Elementary schools and schools that applied for grant money were more likely to re-apply. Produce sampling was the most frequently cited program highlight, and making purchases with program grant money was the most frequently cited challenge.ConclusionOur findings suggest that schools serving students of low socioeconomic status and diverse ethnicities can be recruited into a large program to promote healthy dietary choices and physical activity, especially elementary schools. Effectiveness and institutionalization of the program might be positively affected by fostering local ownership, allowing school personnel who apply for the grant to tailor the program to their individual schools

Trehalose Is A Chemical Attractant In The Establishment Of Coral Symbiosis

Coral reefs have evolved with a crucial symbiosis between photosynthetic dinoflagellates (genus Symbiodinium) and their cnidarian hosts (Scleractinians). Most coral larvae take up Symbiodinium from their environment; however, the earliest steps in this process have been elusive. Here we demonstrate that the disaccharide trehalose may be an important signal from the symbiont to potential larval hosts. Symbiodinium freshly isolated from Fungia scutaria corals constantly released trehalose (but not sucrose, maltose or glucose) into seawater, and released glycerol only in the presence of coral tissue. Spawning Fungia adults increased symbiont number in their immediate area by excreting pellets of Symbiodinium, and when these naturally discharged Symbiodinium were cultured, they also released trehalose. In Y-maze experiments, coral larvae demonstrated chemoattractant and feeding behaviors only towards a chamber with trehalose or glycerol. Concomitantly, coral larvae and adult tissue, but not symbionts, had significant trehalase enzymatic activities, suggesting the capacity to utilize trehalose. Trehalase activity was developmentally regulated in F. scutaria larvae, rising as the time for symbiont uptake occurs. Consistent with the enzymatic assays, gene finding demonstrated the presence of a trehalase enzyme in the genome of a related coral, Acropora digitifera, and a likely trehalase in the transcriptome of F. scutaria. Taken together, these data suggest that adult F. scutaria seed the reef with Symbiodinium during spawning and the exuded Symbiodinium release trehalose into the environment, which acts as a chemoattractant for F. scutaria larvae and as an initiator of feeding behavior- the first stages toward establishing the coral-Symbiodinium relationship. Because trehalose is a fixed carbon compound, this cue would accurately demonstrate to the cnidarian larvae the photosynthetic ability of the potential symbiont in the ambient environment. To our knowledge, this is the first report of a chemical cue attracting the motile coral larvae to the symbiont

Development of selective inhibitors of transglutaminase: phenylthiourea derivatives

L

State Anxiety Is Associated with Cardiovascular Reactivity in Young, Healthy African Americans

Although several studies have shown that enhanced cardiovascular reactivity can predict hypertension development in African Americans, these findings have not been consistent among all studies examining reactivity and hypertension susceptibility. This inconsistency may be explained by the influence of anxiety (state and trait) on the blood pressure response to stress. Therefore, this study sought to determine whether anxiety is associated with blood pressure response to cold pressor (CP) and anger recall (AR) stress tests in young healthy African Americans. Modeling using state and trait anxiety revealed that state anxiety predicts systolic (SBP) and diastolic blood pressure DBP response to CP and AR (P ≤ 0.02). Interestingly, state anxiety predicted heart rate changes only to CP (P < 0.01; P = 0.3 for AR). Although trait anxiety was associated with SBP response to AR and not CP, it was not a significant predictor of reactivity in our models. We conclude that anxiety levels may contribute to the variable blood pressure response to acute stressors and, therefore, should be assessed when performing cardiovascular reactivity measures

Population-based Interventions Engaging Communities of Color in Healthy Eating and Active Living: A Review

INTRODUCTION: The U.S. obesity epidemic is escalating, particularly among communities of color. Obesity control efforts have shifted away from individual-level approaches toward population-based approaches that address socio-cultural, political, economic, and physical environmental factors. Few data exist for ethnic minority groups. This article reviews studies of population-based interventions targeting communities of color or including sufficient samples to permit ethnic-specific analyses. METHODS: Inclusion criteria were established, an electronic database search conducted, and non-electronically catalogued studies retrieved. Findings were aggregated for earlier (early 1970s to early 1990s) and later (mid-1990s to present) interventions. RESULTS: The search yielded 23 ethnically inclusive intervention studies published between January 1970 and May 2003. Several characteristics of inclusive interventions were consistent with characteristics of community-level interventions among predominantly white European-American samples: use of non-interpersonal channels for information dissemination directed at broad spheres of influence (e.g., mass media), promotion of physical activity, and incorporation of social marketing principles. Ethnically inclusive studies, however, also placed greater emphasis on involving communities and building coalitions from study inception; targeting captive audiences; mobilizing social networks; and tailoring culturally specific messages and messengers. Inclusive studies also focused more on community than individual norms. Later studies used "upstream" approaches more than earlier studies. Fewer than half of the inclusive studies presented outcome evaluation data. Statistically significant effects were few and modest, but several studies demonstrated better outcomes among ethnic minority than white participants sampled. CONCLUSION: The best data available speak more about how to engage and retain people of color in these interventions than about how to create and sustain weight loss, regular engagement in physical activity, or improved diet. Advocacy should be directed at increasing the visibility and budget priority of interventions, particularly at the state and local levels

Observations of Giant Pulses from Pulsar PSR B0950+08 using LWA1

We report the detection of giant pulse emission from PSR B0950+08 in 24 hours of observations made at 39.4 MHz, with a bandwidth of 16 MHz, using the first station of the Long Wavelength Array, LWA1. We detected 119 giant pulses from PSR B0950+08 (at its dispersion measure), which we define as having SNRs at least 10 times larger than for the mean pulse in our data set. These 119 pulses are 0.035% of the total number of pulse periods in the 24 hours of observations. The rate of giant pulses is about 5.0 per hour. The cumulative distribution of pulse strength $S$ is a steep power law, $N(>S)\propto S^{-4.7}$, but much less steep than would be expected if we were observing the tail of a Gaussian distribution of normal pulses. We detected no other transient pulses in a dispersion measure range from 1 to 90 pc cm$^{-3}$, in the beam tracking PSR B0950+08. The giant pulses have a narrower temporal width than the mean pulse (17.8 ms, on average, vs. 30.5 ms). The pulse widths are consistent with a previously observed weak dependence on observing frequency, which may be indicative of a deviation from a Kolmogorov spectrum of electron density irregularities along the line of sight. The rate and strength of these giant pulses is less than has been observed at $\sim$100 MHz. Additionally, the mean (normal) pulse flux density we observed is less than at $\sim$100 MHz. These results suggest this pulsar is weaker and produces less frequent giant pulses at 39 MHz than at 100 MHz.Comment: 27 pages, 12 figures, typos correcte