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Public Opinion and the Public Schools: Three Essays on Americans' Education Policy Preferences
Learning About Schooling: The Effects of State Level Student Achievement Data on Public Opinion
There is a growing literature on the effects of student achievement data on public opinion. Prior research suggests that individuals tend to overestimate student achievement in their area. The provision of current achievement levels tends to cause a decrease in confidence in the public schools. In some cases, it appears to increase support for various education reforms. However, previous experimental studies measured outcomes immediately after the provision of information about education performance, making it difficult to distinguish between long-lasting information effects and the more ephemeral consequences of priming. As a result, we do not know how large these effects truly are nor how long they last. I address these concerns by conducting a survey experiment in which I provide state level student achievement data to a randomly assigned treatment group and then measure political attitudes on education issues at three separate times: immediately, after one day, and after ten days. There is evidence that the provision of state level student achievement data temporarily reduces individuals’ confidence in their state school systems, but this effect does not persist after ten days.
Schoolhouse Democracy: Education Policy Responsiveness in the States
The link between public opinion and enacted public policy is referred to as policy responsiveness in the political science literature. Using new estimates of state level public opinion, I explore the relationship between support for increased education spending and average per pupil expenditures at the state level from 1984 to 2013. Within a given year, I find a modest, positive relationship between statewide public opinion on education spending and statewide per pupil expenditures. On average, states with greater support for education spending also tend to spend more per pupil. Within states over time, an increase in support for greater education spending is also associated with an increase in actual spending. However, after controlling for both between-state differences and common trends across states over time, I observe a negative relationship between public opinion and education spending levels. In circumstances in which spending levels are low relative to the state average and low relative to the year average, support for increased education spending tends to be high for that state and year. Additionally, education spending responsiveness tends to be worse in states with weak or non-existent teachers unions.
Polarization and the Politics of Education: What Moves Partisan Opinion?
This study explores the conditions under which partisan polarization and de-polarization occur with respect to public opinion on education issues. To guide this investigation, I pose three general questions. First, does the provision of policy-relevant information cause partisans to converge on the same position? Second, can signals from political elites with ideologically moderate views move partisans closer together? And third, does direct experience with public schools reduce the political abstraction with which one evaluates education policies? I repurpose and extend 17 existing survey experiments to help answer the first two questions, and I conduct a non-experimental data analysis to investigate the third. I find consistent evidence that the provision of education spending information has de-polarizing consequences, but the effects of ideologically moderate elite signals on polarization vary by year. I also find tentative evidence in favor of a link between direct experience with public schools and reduced polarization on education issues
Temperature dependence of breakdown and avalanche multiplication in In0.53Ga0.47As diodes and heterojunction bipolar transistors
The avalanche multiplication and impact ionization coefficients in In/sub 0.53/Ga/sub 0.47/As p-i-n and n-i-p diodes over a range of temperature from 20-400 K were measured and shown to have negative temperature dependence. This is contrary to the positive temperature dependence of the breakdown voltage measured on InP/In/sub 0.53/Ga/sub 0.47/As heterojunction bipolar transistors (HBTs) in this and previous works. It is shown that the collector-base dark current and current gain can be the overriding influence on the temperature dependence of breakdown in InP/In/sub 0.53/Ga/sub 0.47/As HBTs and could explain previous anomalous interpretations from the latter
Anti-inflammatory activity of Punica granatum L. (Pomegranate) rind extracts applied topically to ex vivo skin
Coadministered pomegranate rind extract (PRE) and zinc (II) produces a potent virucidal activity against Herpes simplex virus (HSV); however, HSV infections are also associated with localised inflammation and pain. Here, the objective was to determine the anti-inflammatory activity and relative depth penetration of PRE, total pomegranate tannins (TPT) and zinc (II) in skin, ex vivo. PRE, TPT and ZnSO4 were dosed onto freshly excised ex vivo porcine skin mounted in Franz diffusion cells and analysed for COX-2, as a marker for modulation of the arachidonic acid inflammation pathway, by Western blotting and immunohistochemistry. Tape stripping was carried out to construct relative depth profiles. Topical application of PRE to ex vivo skin downregulated expression of COX-2, which was significant after just 6 h, and maintained for up to 24 h. This was achieved with intact stratum corneum, proving that punicalagin penetrated skin, further supported by the depth profiling data. When PRE and ZnSO4 were applied together, statistically equal downregulation of COX-2 was observed when compared to the application of PRE alone; no effect followed the application of ZnSO4 alone. TPT downregulated COX-2 less than PRE, indicating that tannins alone may not be entirely responsible for the anti-inflammatory activity of PRE. Punicalagin was found throughout the skin, in particular the lower regions, indicating appendageal delivery as a significant route to the viable epidermis. Topical application of TPT and PRE had significant anti-inflammatory effects in ex vivo skin, confirming that PRE penetrates the skin and modulates COX-2 regulation in the viable epidermis. Pomegranates have potential as a novel approach in ameliorating the inflammation and pain associated with a range of skin conditions, including cold sores and herpetic stromal keratitis
Measuring atomic NOON-states and using them to make precision measurements
A scheme for creating NOON-states of the quasi-momentum of ultra-cold atoms
has recently been proposed [New J. Phys. 8, 180 (2006)]. This was achieved by
trapping the atoms in an optical lattice in a ring configuration and rotating
the potential at a rate equal to half a quantum of angular momentum . In this
paper we present a scheme for confirming that a NOON-state has indeed been
created. This is achieved by spectroscopically mapping out the anti-crossing
between the ground and first excited levels by modulating the rate at which the
potential is rotated. Finally we show how the NOON-state can be used to make
precision measurements of rotation.Comment: 14 preprint pages, 7 figure
Potentiated virucidal activity of pomegranate rind extract (PRE) and punicalagin against Herpes simplex virus (HSV) when co-administered with zinc (II) ions, and antiviral activity of PRE against HSV and aciclovir-resistant HSV
Background There is a clinical need for new therapeutic products against Herpes simplex virus (HSV). The pomegranate, fruit of the tree Punica granatum L, has since ancient times been linked to activity against infection. This work probed the activity of pomegranate rind extract (PRE) and co-administered zinc (II) ions. Materials and methods PRE was used in conjunction with zinc (II) salts to challenge HSV-1 and aciclovir-resistant HSV in terms of virucidal plaque assay reduction and antiviral activities in epithelial Vero host cells. Cytotoxicity was determined by the MTS assay using a commercial kit. Results Zinc sulphate, zinc citrate, zinc stearate and zinc gluconate demonstrated similar potentiated virucidal activity with PRE against HSV-1 by up to 4-fold. A generally parabolic relationship was observed when HSV-1 was challenged with PRE and varying concentrations of ZnSO4, with a maximum potentiation factor of 5.5. Punicalagin had 8-fold greater virucidal activity than an equivalent mass of PRE. However, antiviral data showed that punicalagin had significantly lower antiviral activity compared to the activity of PRE (EC50 = 0.56 μg mL-1) a value comparable to aciclovir (EC50 = 0.18 μg mL-1); however, PRE also demonstrated potency against aciclovir-resistant HSV (EC50 = 0.02 μg mL-1), whereas aciclovir showed no activity. Antiviral action of PRE was not influenced by ZnSO4. No cytotoxicity was detected with any test solution. Conclusions The potentiated virucidal activity of PRE by coadministered zinc (II) has potential as a multi-action novel topical therapeutic agent against HSV infections, such as coldsores
In vitro permeation and biological activity of punicalagin and zinc (II) across skin and mucous membranes prone to Herpes simplex virus infection
Coadministration of pomegranate rind extract (PRE) and zinc (II) ions has recently been reported as a potential new topical treatment for Herpes simplex virus (HSV) infections. In the current work we examined the in vitro topical delivery of punicalagin (major phytochemical of PRE) and zinc from hydrogels across epithelial membranes that can become infected with HSV.
Porcine epidermal, buccal and vaginal mucous membranes were excised and mounted in Franz diffusion cells and dosed with a simple hydrogel containing PRE and zinc sulphate (ZnSO4). The permeation of punicalagin and zinc were determined by HPLC and ICPMS respectively; punicalagin was also determined in the basal layers by reverse tape stripping. Receptor phases from the epidermal membrane experiment were also used to challenge HSV-1 in Vero host cells, and ex vivo porcine skin was used to probe COX-2 modulation.
Punicalagin and zinc permeated each of the three test membranes, with significantly greater amounts of both delivered across the epidermal membrane. The amounts of punicalagin permeating the buccal and vaginal membranes were similar, although the amount of zinc permeating the vaginal membrane was comparatively very large – it is known that zinc interacts with vaginal mucosa. The punicalagin recovered by reverse tape stripping of the epidermal, buccal and vaginal membranes gave 0.47 ± 0.016, 0.45 ± 0.052 and 0.51 ± 0.048 nM cm− 2 respectively, and were statistically the same (p < 0.05). A 2.5 log reduction was achieved against HSV-1 using diffusion cell receptor phase, and COX-2 expression was reduced by 64% in ex vivo skin after 6 h.
Overall, a hydrogel containing 1.25 mg mL− 1 PRE and 0.25 M ZnSO4 was able to topically deliver both the major bioactive compound within PRE and Zn (II) across all membranes and into the site specific region of Herpes simplex vesicular clusters, while maintaining potentiated virucidal and anti-inflammatory properties. This novel therapeutic system therefore has potential for the topical treatment of HSV infections
EGFR is required for Wnt9a-Fzd9b signalling specificity in haematopoietic stem cells.
Wnt signalling drives many processes in development, homeostasis and disease; however, the role and mechanism of individual ligand-receptor (Wnt-Frizzled (Fzd)) interactions in specific biological processes remain poorly understood. Wnt9a is specifically required for the amplification of blood progenitor cells during development. Using genetic studies in zebrafish and human embryonic stem cells, paired with in vitro cell biology and biochemistry, we determined that Wnt9a signals specifically through Fzd9b to elicit β-catenin-dependent Wnt signalling that regulates haematopoietic stem and progenitor cell emergence. We demonstrate that the epidermal growth factor receptor (EGFR) is required as a cofactor for Wnt9a-Fzd9b signalling. EGFR-mediated phosphorylation of one tyrosine residue on the Fzd9b intracellular tail in response to Wnt9a promotes internalization of the Wnt9a-Fzd9b-LRP signalosome and subsequent signal transduction. These findings provide mechanistic insights for specific Wnt-Fzd signals, which will be crucial for specific therapeutic targeting and regenerative medicine
Farm Level Comparison of H.R. 2646 and S. 1731
The provisions in the House (H.R. 2646) and Senate (S. 1731) farm bills are analyzed with respect to their impacts on 94 representative crop, livestock, and dairy farms. The analysis incorporates both historical price and production risk for the farms so the “safety net” aspects of the bills can be compared. Representative crop livestock and dairy farms for major production regions across the county are analyzed. Information to describe and simulate these farms comes from a panel of farmers in each local area. The farm panels are reconvened frequently to update their farm’s data. The representative farm data base has been used for policy analysis for more than 15 years. The simulation model used for the analysis was developed by AFPC scientists.Agribusiness, Agricultural and Food Policy,
Effect of Natriuretic Peptide-Guided Therapy on Hospitalization or Cardiovascular Mortality in High-Risk Patients With Heart Failure and Reduced Ejection Fraction: A Randomized Clinical Trial.
Importance: The natriuretic peptides are biochemical markers of heart failure (HF) severity and predictors of adverse outcomes. Smaller studies have evaluated adjusting HF therapy based on natriuretic peptide levels ( guided therapy ) with inconsistent results.
Objective: To determine whether an amino-terminal pro-B-type natriuretic peptide (NT-proBNP)-guided treatment strategy improves clinical outcomes vs usual care in high-risk patients with HF and reduced ejection fraction (HFrEF).
Design, Settings, and Participants: The Guiding Evidence Based Therapy Using Biomarker Intensified Treatment in Heart Failure (GUIDE-IT) study was a randomized multicenter clinical trial conducted between January 16, 2013, and September 20, 2016, at 45 clinical sites in the United States and Canada. This study planned to randomize 1100 patients with HFrEF (ejection fraction ≤40%), elevated natriuretic peptide levels within the prior 30 days, and a history of a prior HF event (HF hospitalization or equivalent) to either an NT-proBNP-guided strategy or usual care.
Interventions: Patients were randomized to either an NT-proBNP-guided strategy or usual care. Patients randomized to the guided strategy (n = 446) had HF therapy titrated with the goal of achieving a target NT-proBNP of less than 1000 pg/mL. Patients randomized to usual care (n = 448) had HF care in accordance with published guidelines, with emphasis on titration of proven neurohormonal therapies for HF. Serial measurement of NT-proBNP testing was discouraged in the usual care group.
Main Outcomes and Measures: The primary end point was the composite of time-to-first HF hospitalization or cardiovascular mortality. Prespecified secondary end points included all-cause mortality, total hospitalizations for HF, days alive and not hospitalized for cardiovascular reasons, the individual components on the primary end point, and adverse events.
Results: The data and safety monitoring board recommended stopping the study for futility when 894 (median age, 63 years; 286 [32%] women) of the planned 1100 patients had been enrolled with follow-up for a median of 15 months. The primary end point occurred in 164 patients (37%) in the biomarker-guided group and 164 patients (37%) in the usual care group (adjusted hazard ratio [HR], 0.98; 95% CI, 0.79-1.22; P = .88). Cardiovascular mortality was 12% (n = 53) in the biomarker-guided group and 13% (n = 57) in the usual care group (HR, 0.94; 95% CI; 0.65-1.37; P = .75). None of the secondary end points nor the decreases in the NT-proBNP levels achieved differed significantly between groups.
Conclusions and Relevance: In high-risk patients with HFrEF, a strategy of NT-proBNP-guided therapy was not more effective than a usual care strategy in improving outcomes.
Trial Registration: clinicaltrials.gov Identifier: NCT01685840
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