1,854 research outputs found

    Beyond High Stakes Testing: Rural High School Students and Their Yearbooks

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    I conducted surveys, focus group interviews, and analyzed the yearbooks of fifty four yearbook students from five rural high schools to investigate students process of yearbook construction and to determine what was meaningful and memorable to them throughout their high school experience. Changs (1992) construct of an adolescent ethos, including the elements of getting along with everyone, being involved, and being independent, provided a conceptual framework, and was affirmed by students responses. References to rites of passage and intensification embedded in the high school program as described by Burnett (1969) confirmed these students perceptions of high school as a four year passage experience

    Concentrations of polybrominated diphenyl ethers (PBDEs) and 2,4,6-tribromophenol in human placental tissues

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    Legacy environmental contaminants such as polybrominated diphenyl ethers (PBDEs) are widely detected in human tissues. However, few studies have measured PBDEs in placental tissues, and there are no reported measurements of 2,4,6-tribromophenol (2,4,6-TBP) in placental tissues. Measurements of these contaminants are important for understanding potential fetal exposures, as these compounds have been shown to alter thyroid hormone regulation in vitro and in vivo. In this study, we measured a suite of PBDEs and 2,4,6-TBP in 102 human placental tissues collected between 2010 and 2011 in Durham County, North Carolina, USA. The most abundant PBDE congener detected was BDE-47, with a mean concentration of 5.09 ng/g lipid (range: 0.12–141 ng/g lipid; detection frequency 91%); however, 2,4,6-TBP was ubiquitously detected and present at higher concentrations with a mean concentration of 15.4 ng/g lipid (range:1.31–316 ng/g lipid; detection frequency 100%). BDE-209 was also detected in more than 50% of the samples, and was significantly associated with 2,4,6-TBP in placental tissues, suggesting they may have a similar source, or that 2,4,6-TBP may be a degradation product of BDE-209. Interestingly, BDE-209 and 2,4,6-TBP were negatively associated with age (rs = − 0.16; p = 0.10 and rs = − 0.17; p = 0.08, respectively). The results of this work indicate that PBDEs and 2,4,6-TBP bioaccumulate in human placenta tissue and likely contribute to prenatal exposures to these environmental contaminants. Future studies are needed to determine if these joint exposures are associated with any adverse health measures in infants and children

    Feasibility of Large High-Powered Solar Electric Propulsion Vehicles: Issues and Solutions

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    Human exploration beyond low Earth orbit will require the use of enabling technologies that are efficient, affordable, and reliable. Solar electric propulsion (SEP) has been proposed by NASA s Human Exploration Framework Team as an option to achieve human exploration missions to near Earth objects (NEOs) because of its favorable mass efficiency as compared to traditional chemical systems. This paper describes the unique challenges and technology hurdles associated with developing a large high-power SEP vehicle. A subsystem level breakdown of factors contributing to the feasibility of SEP as a platform for future exploration missions to NEOs is presented including overall mission feasibility, trip time variables, propellant management issues, solar array power generation, array structure issues, and other areas that warrant investment in additional technology or engineering development

    The interRAI suite of mental health assessment instruments: an integrated system for the continuum of care

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    The lives of persons living with mental illness are affected by psychological, biological, social, economic, and environmental factors over the life course. It is therefore unlikely that simple preventive strategies, clinical treatments, therapeutic interventions, or policy options will succeed as singular solutions for the challenges of mental illness. Persons living with mental illness receive services and supports in multiple settings across the health care continuum that are often fragmented, uncoordinated, and inadequately responsive. Appropriate assessment is an important tool that health systems must deploy to respond to the strengths, preferences, and needs of persons with mental illness. However, standard approaches are often focused on measurement of psychiatric symptoms without taking a broader perspective to address issues like growth, development, and aging; physical health and disability; social relationships; economic resources; housing; substance use; involvement with criminal justice; stigma; and recovery. Using conglomerations of instruments to cover more domains is impractical, inconsistent, and incomplete while posing considerable assessment burden. interRAI mental health instruments were developed by a network of over 100 researchers, clinicians, and policy experts from over 35 nations. This includes assessment systems for adults in inpatient psychiatry, community mental health, emergency departments, mobile crisis teams, and long-term care settings, as well as a screening system for police officers. A similar set of instruments is available for child/youth mental health. The instruments form an integrated mental health information system because they share a common assessment language, conceptual basis, clinical emphasis, data collection approach, data elements, and care planning protocols. The key applications of these instruments include care planning, outcome measurement, quality improvement, and resource allocation. The composition of these instruments and psychometric properties are reviewed, and examples related to homeless are used to illustrate the various applications of these assessment systems

    The All-Data-Based Evolutionary Hypothesis of Ciliated Protists with a Revised Classification of the Phylum Ciliophora (Eukaryota, Alveolata)

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    This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ The file attached is the published version of the article

    Prediction of Breast Cancer-Related Lymphedema By Dermal Backflow Detected With Near-infrared Fluorescence Lymphatic Imaging

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    PURPOSE: Mild breast cancer-related lymphedema (BCRL) is clinically diagnosed as a 5%-10% increase in arm volume, typically measured no earlier than 3-6 months after locoregional treatment. Early BCRL treatment is associated with better outcomes, yet amid increasing evidence that lymphedema exists in a latent form, treatment is typically delayed until arm swelling is obvious. In this study, we investigated whether near-infrared fluorescence lymphatic imaging (NIRF-LI) surveillance could characterize early onset of peripheral lymphatic dysfunction as a predictor of BCRL. METHODS: In a prospective, longitudinal cohort/observational study (NCT02949726), subjects with locally advanced breast cancer who received axillary lymph node dissection and regional nodal radiotherapy (RT) were followed serially, between 2016 and 2021, before surgery, 4-8 weeks after surgery, and 6, 12, and 18 months after RT. Arm volume was measured by perometry, and lymphatic (dys) function was assessed by NIRF-LI. RESULTS: By 18 months after RT, 30 of 42 study subjects (71%) developed mild-moderate BCRL (i.e., ≥ 5% arm swelling relative to baseline), all manifested by dermal backflow of lymph into lymphatic capillaries or interstitial spaces. Dermal backflow had an 83% positive predictive value and 86% negative predictive value for BCRL, with a sensitivity of 97%, specificity of 50%, accuracy of 83%, positive likelihood ratio of 1.93, negative likelihood ratio of 0.07, and odds ratio of 29.00. Dermal backflow appeared on average 8.3 months, but up to 23 months, before the onset of mild BCRL. CONCLUSION: BCRL can be predicted by dermal backflow, which often appears months before arm swelling, enabling early treatment before the onset of edema and irreversible tissue changes

    System-Size Independence of Directed Flow Measured at the BNL Relativistic Heavy-Ion Collider

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    We measure directed flow (ν_1) for charged particles in Au+Au and Cu+Cu collisions at √S_(NN)=200 and 62.4 GeV, as a function of pseudorapidity (η), transverse momentum (p_t), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to ν_1 in different collision systems, and investigate possible explanations for the observed sign change in ν_1(p_t)

    Spectroscopic scanning tunneling microscopy insights into Fe-based superconductors

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    In the first three years since the discovery of Fe-based high Tc superconductors, scanning tunneling microscopy (STM) and spectroscopy have shed light on three important questions. First, STM has demonstrated the complexity of the pairing symmetry in Fe-based materials. Phase-sensitive quasiparticle interference (QPI) imaging and low temperature spectroscopy have shown that the pairing order parameter varies from nodal to nodeless s\pm within a single family, FeTe1-xSex. Second, STM has imaged C4 -> C2 symmetry breaking in the electronic states of both parent and superconducting materials. As a local probe, STM is in a strong position to understand the interactions between these broken symmetry states and superconductivity. Finally, STM has been used to image the vortex state, giving insights into the technical problem of vortex pinning, and the fundamental problem of the competing states introduced when superconductivity is locally quenched by a magnetic field. Here we give a pedagogical introduction to STM and QPI imaging, discuss the specific challenges associated with extracting bulk properties from the study of surfaces, and report on progress made in understanding Fe-based superconductors using STM techniques.Comment: 36 pages, 23 figures, 229 reference

    Spin alignment measurements of the K0(892)K^{*0}(892) and ϕ(1020)\phi(1020) vector mesons at RHIC

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    We present the first spin alignment measurements for the K0(892)K^{*0}(892) and ϕ(1020)\phi(1020) vector mesons produced at mid-rapidity with transverse momenta up to 5 GeV/c at sNN\sqrt{s_{NN}} = 200 GeV at RHIC. The diagonal spin density matrix elements with respect to the reaction plane in Au+Au collisions are ρ00\rho_{00} = 0.32 ±\pm 0.04 (stat) ±\pm 0.09 (syst) for the K0K^{*0} (0.8<pT<5.00.8<p_T<5.0 GeV/c) and ρ00\rho_{00} = 0.34 ±\pm 0.02 (stat) ±\pm 0.03 (syst) for the ϕ\phi (0.4<pT<5.00.4<p_T<5.0 GeV/c), and are constant with transverse momentum and collision centrality. The data are consistent with the unpolarized expectation of 1/3 and thus no evidence is found for the transfer of the orbital angular momentum of the colliding system to the vector meson spins. Spin alignments for K0K^{*0} and ϕ\phi in Au+Au collisions were also measured with respect to the particle's production plane. The ϕ\phi result, ρ00\rho_{00} = 0.41 ±\pm 0.02 (stat) ±\pm 0.04 (syst), is consistent with that in p+p collisions, ρ00\rho_{00} = 0.39 ±\pm 0.03 (stat) ±\pm 0.06 (syst), also measured in this work. The measurements thus constrain the possible size of polarization phenomena in the production dynamics of vector mesons.Comment: 7 pages, 4 figures. fig.1 updated; one more reference added, one typo corrected, published in PRC.77.06190

    Longitudinal double-spin asymmetry for inclusive jet production in p+p collisions at sqrt(s)=200 GeV

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    We report a new STAR measurement of the longitudinal double-spin asymmetry A_LL for inclusive jet production at mid-rapidity in polarized p+p collisions at a center-of-mass energy of sqrt(s) = 200 GeV. The data, which cover jet transverse momenta 5 < p_T < 30 GeV/c, are substantially more precise than previous measurements. They provide significant new constraints on the gluon spin contribution to the nucleon spin through the comparison to predictions derived from one global fit of polarized deep-inelastic scattering measurements.Comment: 7 pages, 4 figures + 1 tabl
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