Internal wave pressure, velocity, and energy flux from density perturbations

Determination of energy transport is crucial for understanding the energy budget and fluid circulation in density varying fluids such as the ocean and the atmosphere. However, it is rarely possible to determine the energy flux field $\mathbf{J} = p \mathbf{u}$, which requires simultaneous measurements of the pressure and velocity perturbation fields, $p$ and $\mathbf{u}$. We present a method for obtaining the instantaneous $\mathbf{J}(x,z,t)$ from density perturbations alone: a Green's function-based calculation yields $p$, and $\mathbf{u}$ is obtained by integrating the continuity equation and the incompressibility condition. We validate our method with results from Navier-Stokes simulations: the Green's function method is applied to the density perturbation field from the simulations, and the result for $\mathbf{J}$ is found to agree typically to within $1\%$ with $\mathbf{J}$ computed directly using $p$ and $\mathbf{u}$ from the Navier-Stokes simulation. We also apply the Green's function method to density perturbation data from laboratory schlieren measurements of internal waves in a stratified fluid, and the result for $\mathbf{J}$ agrees to within $6\%$ with results from Navier-Stokes simulations. Our method for determining the instantaneous velocity, pressure, and energy flux fields applies to any system described by a linear approximation of the density perturbation field, e.g., to small amplitude lee waves and propagating vertical modes. The method can be applied using our Matlab graphical user interface EnergyFlux

Acceptance and Commitment Therapy for the treatment of posttraumatic stress among adolescents

The number of individuals who meet diagnostic criteria for posttraumatic stress disorder (PTSD) is a small percentage of those exposed to trauma; many youth who do not meet criteria for PTSD continue to experience problematic posttraumatic stress (PTS) symptomology. Acceptance and commitment therapy (ACT) has shown preliminary effectiveness in the treatment of adult PTSD, but its effectiveness in treating PTS in youth is unknown. Using a multiple-baseline design, this study investigated the effectiveness of 10-weeks of ACT to treat PTS in youth. Four adolescents from a community sample and three adolescents from a residential sample participated. The Clinician Administered PTSD Scale for Children and Adolescents, Child PTSD Symptom Scale, and Comprehensive Quality of Life Scale were completed at pretreatment, posttreatement, and 3- month follow-up. Individuals reported baseline data for 7 to 66 days. Symptom and process measures were completed at each session. Results revealed a decrease in PTS symptomology across both samples with mean reductions in self-reported PTS symptomology at posttreatment of 69% and 81% for the community and residential samples, respectively, and an overall 68% and 84% respective reduction at follow-up. Reductions in clinician rated measures of PTSD were observed for all participants with mean reductions of 57% and 61% in the community and residential samples at posttreatment, and 71% and 60% at follow-up, respectively. Results provide preliminary support for ACT as a treatment for adolescent PTS. Empirical and clinical implications as well as limitations and future directions are discussed. Key Words: Acceptance and Commitment Therapy; Posttraumatic Stress; PTSD; Treatmen

Stem cells, cancer, and cancer stem cells

Stem cell biology has come of age. Unequivocal proof that stem cells exist in the haematopoietic system has given way to the prospective isolation of several tissue-specific stem and progenitor cells, the initial delineation of their properties and expressed genetic programmes, and the beginnings of their utility in regenerative medicine. Perhaps the most important and useful property of stem cells is that of self-renewal. Through this property, striking parallels can be found between stem cells and cancer cells: tumours may often originate from the transformation of normal stem cells, similar signalling pathways may regulate self-renewal in stem cells and cancer cells, and cancer cells may include 'cancer stem cells'-rare cells with indefinite potential for self-renewal that drive tumorigenesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62862/1/414105a0.pd

Electronic Cash In E-Commerce: Comparative Analysis Of Views Of Hispanic And African-American Business Owners

Based on a survey of 1000 Hispanic and 1000 African-American business owners on the impacts e-commerce and e-cash are expected to have upon business practices, there were significant discrepancies between perceptions of these two groups regarding their ability to track and retain customers and to authenticate the source of e-cash payments.  In addition, while both groups of owners agreed that e-cash will likely replace traditional currency used in commercial transactions between consumers and business, they both are uncertain as to what degree central banks of countries should regulate and how much freedom the private sector should have for developing new forms of e-cash.  Hispanic business owners generally are more receptive to e-commerce viewing it as not making marketing strategies more difficult while African-American owners generally perceive enhanced issues to be resolved

Environmental Correlates of Nesting Success in Red-Shouldered Hawks

We evaluated the influence of weather on reproduction of the Red-shouldered Hawk (Buteo lineatus) in an agricultural landscape in south-central Florida where we found relatively high densities of successfully nesting hawks. We used a generalized linear modeling approach within an information-theoretic framework to examine the influence of total rainfall, rainfall frequency, and temperature on the timing of nesting, nesting success, and productivity of hawks during 1995-2000. The best models indicated an influence of rainfall frequency and laying period on hawk reproduction. During years with less frequent rainfall in the summer and fall months prior to the beginning of the breeding season, fewer pairs attempted to nest, and hawks nested later and had smaller clutch sizes and lower productivity. Hawks that nested later in the breeding season had lower hatching success and lower overall nest success. Although Red-shouldered Hawks are generally reported to inhabit forested landscapes throughout their range, a common feature seems to be a dependence on wetlands and riparian habitat for foraging. We propose that the proportion of wetlands throughout the landscape is a unique aspect of south-central Florida that may allow for persistence of unusually high numbers of hawks

Analysis of Care Coordination for Children with Special Health Care Needs: A Parent\u27s Perspective

Introduction. Care coordination involves organizing patient care activities and sharing information among all of the participants concerned with a patient\u27s care to achieve improved outcomes, a recent national focus. Compared to the national average, a higher percentage of Vermont children are cared for in an office that meets medical home criteria. However, there is limited research on medical home and care coordination for children with special health care needs (CSHCN) in the state of Vermont. Objectives. The goal of this study was to assess family perceptions, knowledge, and attitudes about how well care coordination is working for Vermont families with CSHCN. Methods. A paper and an electronic anonymous survey was developed for Vermont families with CSHCN. The surveys were then distributed by Vermont Family Network and the UVMMC Department of Pediatrics. Focus group interviews were also conducted at Vermont Family Network to provide family insight to explain the quantitative data. Results. 30 participants responded to the survey; only 20 completed it. The overall composite satisfaction score is 54%. This score takes into account 4 questions regarding care coordination satisfaction. Each question was formatted into a numerical value ranging from zero to five, with an overall score of 20 equating to 100% satisfaction. Discussion. Findings indicate that families with CSHCN are not satisfied with the level of care coordination currently provided. Respondents reported many barriers regarding care coordination, including lack of communication among health care providers, insurance coverage, and lack of support during transitional periods in care. Recommended improvements were identified.https://scholarworks.uvm.edu/comphp_gallery/1251/thumbnail.jp

Planetary astronomy

The authors profile the field of astronomy, identify some of the key scientific questions that can be addressed during the decade of the 1990's, and recommend several facilities that are critically important for answering these questions. Scientific opportunities for the 1990' are discussed. Areas discussed include protoplanetary disks, an inventory of the solar system, primitive material in the solar system, the dynamics of planetary atmospheres, planetary rings and ring dynamics, the composition and structure of the atmospheres of giant planets, the volcanoes of IO, and the mineralogy of the Martian surface. Critical technology developments, proposed projects and facilities, and recommendations for research and facilities are discussed

Greenland ice core “signal” characteristics: An expanded view of climate change

The last millenium of Earth history is of particular interest because it documents the environmental complexities of both natural variability and anthropogenic activity. We have analyzed the major ions contained in the Greenland Ice Sheet Project 2 (GISP 2) ice core from the present to ∼674 A.D. to yield an environmental reconstruction for this period that includes a description of nitrogen and sulfur cycling, volcanic emissions, sea salt and terrestrial influences. We have adapted and extended mathematical procedures for extracting sporadic (e.g., volcanic) events, secular trends, and periodicities found in the data sets. Finally, by not assuming that periodic components (signals) were “stationary” and by utilizing evolutionary spectral analysis, we were able to reveal periodic processes in the climate system which change in frequency, “turn on,” and “turn off” with other climate transitions such as\u27that between the little ice age and the medieval warm period