Internal and External Fluctuation Activated Non-equilibrium Reactive Rate Process

The activated rate process for non-equilibrium open systems is studied taking into account both internal and external noise fluctuations in a unified way. The probability of a particle diffusing passing over the saddle point and the rate constant together with the effective transmission coefficient are calculated via the method of reactive flux. We find that the complexity of internal noise is always harmful to the diffusion of particles. However the external modulation may be beneficial to the rate process.Comment: 10 pages, 1 figure (containing 2 subgraphs). arXiv admin note: text overlap with arXiv:cond-mat/9911028 by other author

Infant mortality statistics from the 2006 period linked birth/infant death data set.

The U.S. infant mortality rate was 6.68 infant deaths per 1,000 live births in 2006, a 3 percent decline from 6.86 in 2005. Infant mortality rates ranged from 4.52 per 1,000 live births for Central and South American mothers to 13.35 for non-Hispanic black mothers. Infant mortality rates were higher for those infants whose mothers were born in the 50 states or the District of Columbia, were unmarried, or were born in multiple deliveries. Infant mortality was also higher for male infants and infants born preterm or at low birthweight. The neonatal mortality rate was essentially unchanged in 2006 (4.46) from 2005 (4.54). The postneonatal mortality rate decreased 4 percent, from 2.32 in 2005 to 2.22 in 2006. Infants born at the lowest gestational ages and birthweights have a large impact on overall U.S. infant mortality. For example, more than half of all infant deaths in the United States in 2006 (54 percent) occurred to the 2 percent of infants born very preterm (less than 32 weeks of gestation). Still, infant mortality rates for late preterm infants (34-36 weeks of gestation) were three times those for term infants (37-41 weeks). The three leading causes of infant death--congenital malformations, low birthweight, and sudden infant death syndrome--taken together accounted for 46 percent of all infant deaths. The percentage of infant deaths that were "preterm-related" was 36.1 percent in 2006. The preterm-related infant mortality rate for non-Hispanic black mothers was 3.4 times higher and the rate for Puerto Rican mothers was 84 percent higher than for non-Hispanic white mothers

Infant mortality statistics from the 2004 period linked birth/infant death data set.

The U.S. infant mortality rate was 6.78 infant deaths per 1000 live births in 2004 compared with 6.84 in 2003. Infant mortality rates ranged from 4.67 per 1,000 live births for Asian and Pacific Islander mothers to 13.60 for non-Hispanic black mothers. Among Hispanics, rates ranged from 4.55 for Cuban mothers to 7.82 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers were born in the 50 states and the District of Columbia, were unmarried, or were born in multiple births. Infant mortality was also higher for male infants and infants born preterm or at low birthweight. The neonatal mortality rate declined from 4.63 in 2003 to 4.52 in 2004 while the postneonatal mortality rate was essentially unchanged. Infants born at the lowest gestational ages and birthweights have a large impact on overall U.S. infant mortality. More than one-half (55 percent) of all infant deaths in the United States in 2004 occurred to the 2 percent of infants born at less than 32 weeks of gestation. Still, infant mortality rates for late preterm (34-36 weeks of gestation) infants were three times those for term (37-41 week) infants. The three leading causes of infant death-Congenital malformations, low birthweight, and SIDS-taken together accounted for 45 percent all infant deaths. Results from a new analysis of preterm-related causes of death show that 36.5 percent of infant deaths in 2004 were due to preterm-related causes. The preterm-related infant mortality rate for non-Hispanic black mothers was 3.5 times higher, and the rate for Puerto Rican mothers was 75 percent higher than for non-Hispanic white mothers

Models of Cosmic Order: Physical Expression of Sacred Space Among the Ancient Maya

The archaeological record, as well as written texts, oral traditions, and iconographic representations, express the Maya perception of cosmic order, including the concepts of quadripartite division and layered cosmos. The ritual act of portioning and layering created spatial order and was used to organize everything from the heavens to the layout of altars. These acts were also metaphors for world creation, world order, and establishing the center as a position of power and authority. This article examines the articulations of these concepts from the level of caches to the level of regions from the past and present in an attempt to understand these ancient perceptions. We emphasize that basic organizational notions of the cosmos permeate all societal levels and argue that scholars should expand their focus to include how the sacred landscape and its related ideology were reproduced in the lives of everyday people