378 research outputs found
Feasibility of a Readiness Exam for Predicting Radiography Program Success: A Pilot Study
ABSTRACT
Background: Research investigating predictors of academic success in rigorous health science education is valuable for curricular intervention for identified at-risk students. Various predictors of success have been investigated, but the literature is insufficient when examining anatomy and physiology readiness scores as they correlate to radiography curricular success. This pilot study assessed the correlation between readiness exam scores and programmatic course GPA to determine if the scores could be used as a metric for identifying academic success resources for incoming students. Cohorts of the radiography program at a midwestern health sciences center demonstrated a longitudinal trend of difficulty with anatomy and physiology programmatic coursework. Therefore, researchers set out to investigate whether or not readiness exam scores, in addition to the metrics they were already utilizing, could be used as a tool for early academic remediation. Objective: The objective of this study was to determine if the anatomy and physiology readiness exam scores would be reliable indicators of programmatic success in anatomy and physiology program coursework. Design: This investigation occurred in two phases: a retrospective correlational phase and a quasi-experimental phase. Methods: Retrospective data from cohorts that matriculated between 2013 and 2017 (n=91) was collected and de-identified. Data included prerequisite grade point average (GPA) and grades from anatomy and physiology course taken during the program. During the quasi-experimental phase, a sample of students (n=18) completed a readiness examination. The scores from this examination were correlated with prerequisite GPA and program anatomy and physiology GPA. Results: Data analysis revealed prerequisite GPA and the anatomy and physiology section of the readiness examination to be strong and moderate predictors of programmatic anatomy and physiology course grades, respectively. Conclusion: Predictors of curricular success in a radiography program’s anatomy and physiology coursework are essential factors to consider in relation to admissions practices, curricular prerequisite standards, and on-boarding of new students, especially those identified as at-risk
Incidental Findings on Brain MRI in People with HIV Infection
BACKGROUND: Incidental findings are a well-known complication of imaging studies done for both diagnostic and research purposes. Little is known about the rates and types of incidental findings found on brain MRI in patients with HIV infection, who may be at risk for HIV-Associated Neurocognitive Disorders (HAND).
METHODS: The parent study included 108 adults with HIV infection and 125 demographically-matched uninfected controls who completed MRI and neuropsychological testing. Incidental findings were classified by the study team as vascular, neoplastic, congenital, other neurologic, or non-neurologic. Categorical measures were compared using Pearson chi-square tests; continuous measures were compared using t-tests.
RESULTS: Among participants with HIV infection, 36/108 (33%) had incidental findings compared to 33/125 (26%) controls (p = 0.248). Rates of incidental findings were significantly correlated with increasing age in both participants with HIV infection (p = 0.013) and controls (p = 0.022). We found no correlation between presence of incidental findings and sex or race/ethnicity among either cohort, and no correlation with CD4 count or HAND status for the HIV-infected cohort.
CONCLUSIONS: Incidental findings were common in both participants with HIV infection and controls, at higher rates than previously reported in healthy populations. There was no significant difference in prevalence between the groups
Sensors and Systems for in situ Observations of Marine Carbon Dioxide System Variables
Autonomous chemical sensors are required to document the marine carbon dioxide system's evolving response to anthropogenic CO2 inputs, as well as impacts on short- and long-term carbon cycling. Observations will be required over a wide range of spatial and temporal scales, and measurements will likely need to be maintained for decades. Measurable CO2 system variables currently include total dissolved inorganic carbon (DIC), total alkalinity (AT), CO2 fugacity (fCO2), and pH, with comprehensive characterization requiring measurement of at least two variables. These four parameters are amenable to in situ analysis, but sustained deployment remains a challenge. Available methods encompass a broad range of analytical techniques, including potentiometry, spectrophotometry, conductimetry, and mass spectrometry. Instrument capabilities (precision, accuracy, endurance, reliability, etc.) are diverse and will evolve substantially over the time that the marine CO2 system undergoes dramatic changes. Different suites of measurements/parameters will be appropriate for different sampling platforms and measurement objectives
A Pharmacist-Led Medication Switch Protocol in an Academic HIV Clinic: Patient Knowledge and Satisfaction
BACKGROUND: Tenofovir alafenamide (TAF) is associated with less renal and bone toxicity compared with tenofovir disoproxil (TDF). TAF\u27s recent FDA approval has spurred HIV providers to consider switching antiretroviral therapy (ART) regimens containing TDF to TAF to minimize long term risks. Patient views on the process of such medication switches have not been explored.
METHODS: Patients taking elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF) following the Food and Drug Administration\u27s (FDA) approval of elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) received medication education from an HIV pharmacist prior to switching to the tenofovir alafenamide (TAF) formulation. Patients were asked to complete a cross-sectional survey assessing satisfaction with the switch process and knowledge about the new medication 4 to 8 weeks post-switch.
RESULTS: Sixty five patients completed the switch and 57 (88%) completed a follow-up survey. Most (86%) reported understanding why the switch was made, while 91% correctly identified that TAF is associated with reduced renal toxicity, and 73% correctly identified that TAF is associated with reduced bone toxicity. No statistically significant difference was found in satisfaction with or understanding of why the medication switch was made when assessed by sex, age, race, or education, but there was a trend toward significance in the distribution of answers based on education level with those with a high school diploma, General Educational Development (GED) or less being more likely to be satisfied with the medication switch (p = 0.074).
CONCLUSIONS: Education from an ambulatory clinic-based HIV pharmacist resulted in high rates of patient satisfaction and understanding of the switch from TDF to TAF-containing ART
Pressure induced superconductivity in the charge density wave compound TbTe3
A series of high-pressure resistivity measurements on single crystals of
TbTe3 reveal a complex phase diagram involving the interplay of
superconducting, antiferromagnetic and charge density wave orders. The onset of
superconductivity reaches a maximum of ~ 3.5 K (onset) near 75 kbar.Comment: 4 pages, 4 figures; magnetization figure removed due to space
constraints; accepted for publication in Physical Review Letter
Enhancing firm performance through internal market orientation and employee organizational commitment
Considering the importance of retaining key staff and managing the negative impact of high labor turnover on firm performance, this study investigates the notion of internal market orientation (IMO) as an employee management tool for helping companies retain employees and leverage performance via their organizational commitment.
Drawing on data from three different managerial respondents in 275 companies based in China, the findings demonstrate the precedential effect of IMO on corporate performance through employees’ organizational commitment and retention. Inter-departmental relationship and interdepartmental communication, together with ownership types are identified as potential moderating variables, which may vary IMO’s effectiveness in the framework.
This study provides scholars and practitioners with empirical evidence of IMO’s contribution to different industries and markets. Building on a western perspective, this study extends the literature in an emerging market context and specifically has implications for managing Chinese employees
Insights on geochemical cycling of U, Re and Mo from seasonal sampling in Boston Harbor, Massachusetts, USA
Author Posting. © The Author(s), 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 71 (2007): 895-917, doi:10.1016/j.gca.2006.10.016.This study examined the removal of U, Mo, and Re from seawater by
sedimentary processes at a shallow-water site with near-saturation bottom water O2 levels
(240-380 ÎĽmol O2/L), very high organic matter oxidation rates (annually averaged rate is
870 ÎĽmol C/cm2/y), and shallow oxygen penetration depths (4 mm or less throughout the
year). Under these conditions, U, Mo, and Re were removed rapidly to asymptotic pore
water concentrations of 2.2–3.3 nmol/kg (U), 7–13 nmol/kg (Mo), and 11–14 pmol/kg
(Re). The order in which the three metals were removed, determined by fitting a
diffusion-reaction model to measured profiles, was Re < U < Mo. Model fits also suggest
that the Mo profiles clearly showed the presence of a near-interface layer in which Mo
was added to pore waters by remineralization of a solid phase. The importance of this
solid phase source of pore water Mo increased from January to October as the organic
matter oxidation rate increased, bottom water O2 decreased, and the O2 penetration depth
decreased. Experiments with in situ benthic flux chambers generally showed fluxes of U
and Mo into the sediments. However, when the overlying water O2 concentration in the
chambers was allowed to drop to very low levels, Mn and Fe were released to the
overlying water along with the simultaneous release of Mo and U. These experiments
suggest that remineralization of Mn and/or Fe oxides may be a source of Mo and perhaps
U to pore waters, and may complicate the accumulation of U and Mo in bioturbated
sediments with high organic matter oxidation rates and shallow O2 penetration depths.
Benthic chamber experiments including the nonreactive solute tracer, Br-,
indicated that sediment irrigation was very important to solute exchange at the study site.
The enhancement of sediment-seawater exchange due to irrigation was determined for
the nonreactive tracer (Br-), TCO2, NH4
+, U and Mo. The comparisons between these
solutes showed that reactions within and around the burrows were very important for
modulating the Mo flux, but less important for U. The effect of these reactions on Mo
exchange was highly variable, enhancing Mo (and, to a lesser extent, U) uptake at times
of relatively modest irrigation, but inhibiting exchange when irrigation rates were faster.
These results reinforce the observation that Mo can be released to and removed from pore
waters via sedimentary reactions.
The removal rate of U and Mo from seawater by sedimentary reactions was found
to agree with the rate of accumulation of authigenic U and Mo in the solid phase. The
fluxes of U and Mo determined by in situ benthic flux chamber measurements were the
largest that have been measured to date. These results confirm that removal of redoxsensitive
metals from continental margin sediments underlying oxic bottom water is
important, and suggest that continental margin sediments play a key role in the marine
budgets of these metals.We appreciate the financial support
from the National Science Foundation (OCE-0220892). Funding for this work was also
provided to JLM by the Postdoctoral Scholar Program at WHOI courtesy of the Cabot
Marine Environmental Science Fund and the J. Seward Johnson Fund. Financial support
to IMK was given by The Swedish Foundation for International Cooperation in Research
and Higher Education
A model for uranium, rhenium, and molybdenum diagenesis in marine sediments based on results from coastal locations
Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 73 (2009): 2938-2960, doi:10.1016/j.gca.2009.02.029.The purpose of this research is to characterize the mobilization and
immobilization processes that control the authigenic accumulation of uranium (U),
rhenium (Re) and molybdenum (Mo) in marine sediments. We analyzed these redox–
sensitive metals (RSM) in benthic chamber, pore water and solid phase samples at a site
in Buzzards Bay, Massachusetts, U.S.A., which has high bottom water oxygen
concentrations (230–300 mol/L) and high organic matter oxidation rates (390 mol
C/cm2/y). The oxygen penetration depth varies from 2–9 mm below the sediment–water
interface, but pore water sulfide is below detection (< 2M). The RSM pore water
profiles are modeled with a steady–state diagenetic model that includes irrigation, which
extends 10–20 cm below the sediment–water interface. To present a consistent
description of trace metal diagenesis in marine sediments, RSM results from sediments in
Buzzards Bay are compared with previous research from sulfidic sediments (Morford et
al., GCA 71).
Release of RSM to pore waters during the remineralization of solid phases occurs
near the sediment–water interface at depths above the zone of authigenic RSM formation.
This release occurs consistently for Mo at both sites, but only in the winter for Re in
Buzzards Bay and intermittently for U. At the Buzzards Bay site, Re removal to the solid
phase extends to the bottom of the profile, while the zone of removal is restricted to ~2–9
cm for U and Mo. Authigenic Re formation is independent of the anoxic
remineralization rate, which is consistent with an abiotic removal mechanism. The rate
of authigenic U formation and its modeled removal rate constant increase with increasing
anoxic remineralization rates, and is consistent with U reduction being microbially
mediated. Authigenic Mo formation is related to the formation of sulfidic
microenvironments. The depth and extent of Mo removal from pore water is closely
associated with the balance between iron and sulfate reduction and the consumption of
pore water sulfide via iron sulfide formation. Pore water RSM reach constant asymptotic
concentrations in sulfidic sediments, but only pore water Re is constant at depth in
Buzzards Bay. The increases in pore water U at the Buzzards Bay site are consistent with
addition via irrigation and subsequent upward diffusion to the removal zone. Deep pore
water Mo concentrations exceed its bottom water concentration due to irrigation–induced
oxidation and remobilization from the solid phase. In sulfidic sediments, there is no
evidence for higher pore water U or Mo concentrations at depth due to the absence of
irrigation and/or the presence of more stable authigenic RSM phases.
There are good correlations between benthic fluxes and authigenic accumulation
rates for U and Mo in sulfidic sediments. However, results from Buzzards Bay suggest
irrigation ultimately results in the partial loss of U and Mo from the solid phase, with
accumulation rates that are 20–30% of the modeled flux. Irrigation can augment (Re,
possibly U) or compromise (U, Mo) authigenic accumulation in sediments, and is
important when determining burial rates in continental margin sediments.The authors also acknowledge financial support from the National Science Foundation
(JLM, WRM: OCE–0220892), Research Corporation (JLM, CMC), Franklin & Marshall
College, and the Hackman Summer Research Program at F&M
Chronic cisplatin treatment promotes enhanced damage repair and tumor progression in a mouse model of lung cancer
Chemotherapy resistance is a major obstacle in cancer treatment, yet the mechanisms of response to specific therapies have been largely unexplored in vivo. Employing genetic, genomic, and imaging approaches, we examined the dynamics of response to a mainstay chemotherapeutic, cisplatin, in multiple mouse models of human non-small-cell lung cancer (NSCLC). We show that lung tumors initially respond to cisplatin by sensing DNA damage, undergoing cell cycle arrest, and inducing apoptosis—leading to a significant reduction in tumor burden. Importantly, we demonstrate that this response does not depend on the tumor suppressor p53 or its transcriptional target, p21. Prolonged cisplatin treatment promotes the emergence of resistant tumors with enhanced repair capacity that are cross-resistant to platinum analogs, exhibit advanced histopathology, and possess an increased frequency of genomic alterations. Cisplatin-resistant tumors express elevated levels of multiple DNA damage repair and cell cycle arrest-related genes, including p53-inducible protein with a death domain (Pidd). We demonstrate a novel role for PIDD as a regulator of chemotherapy response in human lung tumor cells.National Institutes of Health (U.S.) (grant 5-UO1-CA84306)National Cancer Institute (U.S.) (CA034992
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