Large-scale structure formation for power spectra with broken scale invariance

We have simulated the formation of large-scale structure arising from COBE-normalized spectra computed by convolving a primordial double-inflation perturbation spectrum with the CDM transfer function. Due to the broken scale invariance ('BSI') characterizing the primordial perturbation spectrum, this model has less small-scale power than the (COBE-normalized) standard CDM model. The particle-mesh code (with $512^3$ cells and $256^3$ particles) includes a model for thermodynamic evolution of baryons in addition to the usual gravitational dynamics of dark matter. It provides an estimate of the local gas temperature. In particular, our galaxy-finding procedure seeks peaks in the distribution of gas that has cooled. It exploits the fact that ``cold" particles trace visible matter better than average and thus provides a natural biasing mechanism. The basic picture of large-scale structure formation in the BSI model is the familiar hierarchical clustering scenario. We obtain particle in cell statistics, the galaxy correlation function, the cluster abundance and the cluster-cluster correlation function and statistics for large and small scale velocity fields. We also report here on a semi-quantitative study of the distribution of gas in different temperature ranges. Based on confrontation with observations and comparison with standard CDM, we conclude that the BSI scenario could represent a promising modification of the CDM picture capable of describing many details of large-scale structure formation.Comment: 15 pages, Latex using mn.sty, uuencoded compressed ps-file with 15 figures by anonymous ftp to ftp://ftp.aip.de/incoming/mueller/bsi.u

Recent aspects on outcomes in geriatric fracture patients

As the population ages, the number of fragility fractures is expected to increase dramatically. These injuries are frequently associated with less than satisfactory outcomes. Many of the patients experience adverse events or death, and few regain their pre-injury functional status. Many also lose their independence as a result of their fracture. This manuscript will explore problems and some potential solutions to evaluate the outcomes of geriatric fracture care. Specific, system-wide, and societal concerns will be discussed. Limited suggestions will be made for future steps to improve outcomes assessment

Fall 1969

Massachusetts Lawn and Turf Grass CouncilBetter Turf Through Research and Education Artificial Turf Faces Credibility Gab by Dr. Gene C. Nutter (page 1) Nitrogen Facts and Fallacies by W.H. Garman (2) DDT Opponents by Charles Wurster, Jr. (10) DDT Defenders by Charles Wurster, Jr. (11) What Type 2,4-D to Use? by J.S. Coartney and A.H. Kates (21) Irrigation Circuit Break Pinpointed in One Hour (24

A comparison of FreeSurfer-generated data with and without manual intervention

This paper examined whether FreeSurfer - generated data differed between a fully – automated, unedited pipeline and an edited pipeline that included the application of control points to correct errors in white matter segmentation. In a sample of 30 individuals, we compared the summary statistics of surface area, white matter volumes, and cortical thickness derived from edited and unedited datasets for the 34 regions of interest (ROIs) that FreeSurfer (FS) generates. To determine whether applying control points would alter the detection of significant differences between patient and typical groups, effect sizes between edited and unedited conditions in individuals with the genetic disorder, 22q11.2 deletion syndrome (22q11DS) were compared to neurotypical controls. Analyses were conducted with data that were generated from both a 1.5 tesla and a 3 tesla scanner. For 1.5 tesla data, mean area, volume, and thickness measures did not differ significantly between edited and unedited regions, with the exception of rostral anterior cingulate thickness, lateral orbitofrontal white matter, superior parietal white matter, and precentral gyral thickness. Results were similar for surface area and white matter volumes generated from the 3 tesla scanner. For cortical thickness measures however, seven edited ROI measures, primarily in frontal and temporal regions, differed significantly from their unedited counterparts, and three additional ROI measures approached significance. Mean effect sizes for edited ROIs did not differ from most unedited ROIs for either 1.5 or 3 tesla data. Taken together, these results suggest that although the application of control points may increase the validity of intensity normalization and, ultimately, segmentation, it may not affect the final, extracted metrics that FS generates. Potential exceptions to and limitations of these conclusions are discussed

Retarded coordinates based at a world line, and the motion of a small black hole in an external universe

In the first part of this article I present a system of retarded coordinates based at an arbitrary world line of an arbitrary curved spacetime. The retarded-time coordinate labels forward light cones that are centered on the world line, the radial coordinate is an affine parameter on the null generators of these light cones, and the angular coordinates are constant on each of these generators. The spacetime metric in the retarded coordinates is displayed as an expansion in powers of the radial coordinate and expressed in terms of the world line's acceleration vector and the spacetime's Riemann tensor evaluated at the world line. The formalism is illustrated in two examples, the first involving a comoving world line of a spatially-flat cosmology, the other featuring an observer in circular motion in the Schwarzschild spacetime. The main application of the formalism is presented in the second part of the article, in which I consider the motion of a small black hole in an empty external universe. I use the retarded coordinates to construct the metric of the small black hole perturbed by the tidal field of the external universe, and the metric of the external universe perturbed by the presence of the black hole. Matching these metrics produces the MiSaTaQuWa equations of motion for the small black hole.Comment: 20 pages, revtex4, 2 figure

Supporting Maine’s Families: Recommendations from Maine\u27s Relatives as Parents Project

Maine is experiencing an increasing rate of children being raised by their grandparents or other relatives. The common reasons these individuals have taken on the responsibility of surrogate parenting, when the biological parents are unwilling or unable to do so include drug and alcohol abuse, child abuse and neglect, mental health problems, illness and death, incarceration and family violence. Under the vast majority of circumstances, relatives take responsibility for these children instead of the State Child Protective Services; this saves the State money but can be very burdensome to the family. Though relatives welcome the children, they often face unexpected lifestyle changes. The challenges they face can be physically, emotionally, and financially overwhelming, compromising their capacity to provide unconditional love, build trust, and serve as strong adult role models. It is in the interest of Maine’s children and families to support relatives in assuming this responsibility. These caregivers - often called kinship caregivers - take on this responsibility because they want to keep their families together; they love their grandchildren and want to keep them healthy and safe. The availability of responsive policies and programs have the capacity to alleviate stress and improve health and also help reduce the sense of isolation often felt by older adults raising children. During 2002-2003, the University of Maine Center on Aging, with a grant from Generations United, sponsored the Relatives as Parents Project Task Force to develop recommendations on how Maine can better support families in relative-headed households. Three subcommittees grew out of Maine’s RAPP Task Force and the recommendations presented here reflect the work of those three groups. The foci of these subcommittees were: financial security, community resources, and mental health and substance abuse issues

Dynamical effects of the neutrino gravitational clustering at Planck angular scales

We study the CMB anisotropy induced by the non-linear perturbations in the massive neutrino density associated to the non-linear gravitational clustering proceses. Our results show that for the neutrino fraction in agreement with that indicated by the astroparticle and nuclear physics experiments and a cosmological accreting mass comparable with the mass of known clusters, the angular resolution and the sensitivity of the CMB anisotropy measurements from the Planck surveyor will allow the detection of the dynamical effects of the neutrino gravitational clustering.Comment: 40 pages and 12 figures, submitted to ApJ (14 March 2002

Luminosity- and morphology-dependent clustering of galaxies

How does the clustering of galaxies depend on their inner properties like morphological type and luminosity? We address this question in the mathematical framework of marked point processes and clarify the notion of luminosity and morphological segregation. A number of test quantities such as conditional mark-weighted two-point correlation functions are introduced. These descriptors allow for a scale-dependent analysis of luminosity and morphology segregation. Moreover, they break the degeneracy between an inhomogeneous fractal point set and actual present luminosity segregation. Using the Southern Sky Redshift Survey~2 (da Costa et al. 1998, SSRS2) we find both luminosity and morphological segregation at a high level of significance, confirming claims by previous works using these data (Benoist et al. 1996, Willmer et al. 1998). Specifically, the average luminosity and the fluctuations in the luminosity of pairs of galaxies are enhanced out to separations of 15Mpc/h. On scales smaller than 3Mpc/h the luminosities on galaxy pairs show a tight correlation. A comparison with the random-field model indicates that galaxy luminosities depend on the spatial distribution and galaxy-galaxy interactions. Early-type galaxies are also more strongly correlated, indicating morphological segregation. The galaxies in the PSCz catalog (Saunders et al. 2000) do not show significant luminosity segregation. This again illustrates that mainly early-type galaxies contribute to luminosity segregation. However, based on several independent investigations we show that the observed luminosity segregation can not be explained by the morphology-density relation alone.Comment: aastex, emulateapj5, 20 pages, 13 figures, several clarifying comments added, ApJ accepte

Mapping Cortical Morphology in Youth With Velocardiofacial (22q11.2 Deletion) Syndrome

Objective: Velo-cardio-facial syndrome (VCFS; 22q11.2 deletion syndrome) represents one of the highest known risk factors for schizophrenia. Insofar as up to thirty percent of individuals with this genetic disorder develop schizophrenia, VCFS constitutes a unique, etiologically homogeneous model for understanding the pathogenesis of schizophrenia. Method: Using a longitudinal, case-control design, we acquired anatomic magnetic resonance images to investigate both cross-sectional and longitudinal alterations in surface cortical morphology in a cohort of adolescents with VCFS and age-matched typical controls. All participants were scanned at two time points. Results: Relative to controls, youth with VCFS exhibited alterations in inferior frontal, dorsal frontal, occipital, and cerebellar brain regions at both time points. We observed little change over time in surface morphology of either study group. However, within the VCFS group only, worsening psychosocial functioning over time was associated with Time 2 surface contractions in left middle and inferior temporal gyri. Further, prodromal symptoms at Time 2 were associated with surface contractions in left and right orbitofrontal, temporal and cerebellar regions, as well as surface protrusions of supramarginal gyrus. Conclusions: These findings advance our understanding of cortical disturbances in VCFS that produce vulnerability for psychosis in this high risk population

Definition of infection after fracture fixation: A systematic review of randomized controlled trials to evaluate current practice

Introduction: One of the most challenging musculoskeletal complications in modern trauma surgery is infection after fracture fixation (IAFF). Although infections are clinically obvious in many cases, a clear definition of the term IAFF is crucial, not only for the evaluation of published research data but also for the establishment of uniform treatment concepts. The aim of this systematic review was to identify the definitions used in the scientific literature to describe infectious complications after internal fixation of fractures. The hypothesis of this study was that the majority of fracture-related literature do not define IAFF. Material and methods: A comprehensive search was performed in Embase, Cochrane, Google Scholar, Medline (OvidSP), PubMed publisher and Web-of-Science for randomized controlled trials (RCTs) on fracture fixation. Data were collected on the definition of infectious complications after fracture fixation used in each study. Study selection was accomplished through two phases. During the first phase, titles and abstracts were reviewed for relevance, and the full texts of relevant articles were obtained. During the second phase, full-text articles were reviewed. All definitions were literally extracted and collected in a database. Then, a classification was designed to rate the quality of the description of IAFF. Results: A total of 100 RCT’s were identified in the search. Of 100 studies, only two (2%) cited a validated definition to describe IAFF. In 28 (28%) RCTs, the authors used a self-designed definition. In the other 70 RCTs, (70%) there was no description of a definition in the Methods section, although all of the articles described infections as an outcome parameter in the Results section. Conclusion: This systematic review shows that IAFF is not defined in a large majority of the fracture-related literature. To our knowledge, this is the first study conducted with the objective to explore this important issue. The lack of a consensus definition remains a problem in current orthopedic trauma research and treatment and this void should be addressed in the near future