Expanding the Supply of High Quality Public Schools

Two levers that play critically important roles in determining how quickly and consistently successful schools and design models can be replicated. One is the degree of managerial responsibility, support, and control the organization chooses to exercise. The other is related to specificity of school design.This paper examines the school development landscape in the context of these levers, with examples of organizations that have chosen different paths with different tradeoffs and outcomes

Portland Public Schools: From Data and Decisions to Implementation and Results on Dropout Prevention

Many school district leaders, particularly those in urban areas, struggle to reduce dropout rates, but find themselves overwhelmed by the dimensions of the problem. There are, however, a few districts making notable progress towards reducing the number of dropouts and ensuring that students earn high school diplomas in a timely manner.One of these is the Portland, Oregon, Public Schools (PPS). In the course of a single calendar year (2007-2008) PPS began to have a positive impact in addressing its dropout problem. How? The key was gathering data that illuminated the true scope of the problem, identifying predictive indicators to spot high risk students, and then marshalling teachers, administrators and support services to focus on those individual students entering 9th grade who were at the highest risk of dropping out of high school

Pathogenicity studies on verocytotoxin-producing Escherichia coli : bacterial adhesion, toxin expression and uptake

Verotoxin-producing Escherichia coli (VTEC) are a group of medically important bacteria which have been implicated in cases of haemorrhagic colitis and haemolytic uraemic syndrome. They are characterised by the ability to produce Verotoxins (VT), potent exotoxins which kill mammalian cells by inhibiting protein synthesis. Two distinct VT are known, Verotoxin 1 (VT1) and Verotoxin 2 (VT2), and variants of VT2 have been described. VTEC adhere to intestinal cells via an attaching-effacing mechanism and many strains carry a 60-MDa plasmid which was thought to be involved in adhesion. Attachment of VTEC is thought to be an important pathogenic mechanism since it allows colonisation to occur, and facilitates delivery of toxin. The exact mechanisms of VTEC infection, however, especially the variation in severity of disease have not been established. This study aimed to investigate the putative virulence attributes of VTEC, namely toxin production and bacterial attachment. In order to study the toxins, it was first necessary to develop a reliable method of assay, and for this, two assays were chosen; a Vero cell assay which measured biological activity, and a colony ELISA, which detected the presence of toxin antigens. Since VT are produced by lysogenic phages, the effect of a phage inducer, mitomycin C, on VT production, was investigated. Increased levels of VT appeared to be detected and SDS-PAGE analysis of extracellular proteins revealed that the amount of toxin, and other phage proteins increased in the presence of mitomycin C, whilst bacterial protein levels remained constant. This effect was not seen when a non-VTEC strain was tested. The specific activity of VT increased inside the cell, where bacterial protein synthesis had ceased, but decreased extracellularly due to cell lysis. Extracellular phage particles were demonstrated by plaque assay. Mutants of 0157:H7 strain ATCC 35150, were produced by chemical mutagenesis. They did not possess the 60-MDa plasmid, found in the parent strain, and had an altered biochemical profile. Immunological assays revealed that they were altered in the O side chain of the LPS and it was shown by immunoblotting, that only the major outer membrane proteins reacted with anti-0157:H7 although they were not rough mutants. Analysis of the LPS neutral sugars showed that the mutants contained rhamnose, instead of fucose which was present in the parent strain. Despite these changes, however, the hydrophobicity of the mutants, or their ability to attach to colonic mucus or HeLa cells was unaffected, indicating that the 60-MDa plasmid is not significant in attachment. The mutants appeared to produce toxin with little activity, which was also biologically unstable. Secretion of the toxin appeared to be reduced, possibly as a result of the LPS mutations. The internalisation and intracellular processing of VT1 and VT2 was studied, and it was shown that the toxins were internalised by receptor- mediated endocytosis, but could probably by-pass this pathway. There was no requirement for exposure to an acidic environment, although fusion of endosomes with lysosomes was essential. It was also necessary for cells to possess physiologically functioning calcium channels for intoxication to occur

Different Forms of Vanadate on Sugar Transport in Insulin Target and Nontarget Cells

The effects of several vanadates (ie, orthovanadate, pervanadate, and two stable peroxovanadium compounds) on basal and insulin-stimulated 2-DG transport in insulin target and nontarget cell lines are reported, herein. In nontarget cells, exposure to vanadates (5 × 10(−6) to 10(−4) mol/L) resulted in 2-DG transport stimulatory responses similar to those observed in 2-DG transport post exposure to 667 nmol/L insulin alone, or insulin in combination with vanadates. In 3T3-L1 adipocytes and L6 myotubes, exposure to a vanadate compound or 67 nmol/L insulin, stimulated 2-DG transport dramatically. Again, this effect on stimulated transport was similar to 2-DG transport post-treatment with the effective vanadates in combination with insulin. While pervanadate or stable peroxovanadates stimulated 2-DG transport at 10(−5) to 10(−6) mol/L, orthovanadate up to 10(−4) mol/L was not effective in stimulating 2-DG transport in any of the cell lines tested. The data indicate that the various peroxovanadates are clearly superior insulin mimetics while a more limited insulin mimesis is observed with orthovanadate over a wide variety of cell types

Broadband Access, District Policy, and Student Opportunities for Remote Learning During COVID-19 School Closures

We conceptualize students’ opportunities to learn remotely during the initial school closures associated with the COVID-19 pandemic. We then examine variation in remote instruction using an original statewide survey of teachers in Tennessee, deployed just a few weeks into the closures. Using three-level logistic regression models, we explore potential predictors of regular remote instruction, including prepandemic measures of broadband access, the demographic composition of schools, and measures of district policy responses created from districts’ public COVID-19 plans. We find that teachers in schools serving more economically disadvantaged students and in rural districts are less likely to report regular remote instruction, especially via providing digital resources and holding virtual classes or tutoring. Fewer opportunities for Tennessee’s rural students appear driven in part by lower community access to high-speed broadband, but district policies to distribute technology may partially mitigate this gap in access

Early Holocene Occupation at the West Lost River Site, Klamath County, Oregon

Excavations at the West Lost River Site (35KL972) provide new insights on early Holocene occupation of southwestern Oregon. The article focuses on the artifacts and specimens recovered from the site

The effects of estradiol-17β on the sex reversal, survival, and growth of green sunfish Lepomis cyanellus

The feminization of green sunfish Lepomis cyanellus could expand their utility as a game fish or aquacultured species by preventing overcrowding and precocious reproduction in stocked systems. Feminization of green sunfish could also help elucidate information on their sex determination system. We report the feminization of green sunfish cohorts via oral administration of estradiol-17β (E2) during early development. A low-dose (100 E2 mg per kg of diet) and a high-dose (150 E2 mg per kg of diet) experimental E2 treatment were fed to juvenile green sunfish from 30 to 90 days post-hatch. Fish were subsequently evaluated for any treatment effect on gonadal development, survival, and growth. Both E2 treatments resulted in 100% feminization, with no morphological or histological differences detected between E2 treated ovaries and those from a control group. The control group was composed mostly of males (82.61%). Overall, there was no effect of E2 on survival (P = 0.310) and growth rate data suggested no statistical differences (P = 0.0805). However, the growth rate of the high-dose group increased slightly higher after the treatment ended than the other treatments (P = 0.042), suggesting that E2 might suppress growth in green sunfish. In addition, the control group did not exhibit a higher survival rate after the treatment period ended (P = 0.266), whereas both E2 treated groups did (P = 0.0003–0.0050). We found that the low dose, 100 E2 mg per kg of diet, was sufficient for fully feminizing green sunfish if administered during development from 30 to 90 days post-hatch and E2 dosages may result in deleterious effects on green sunfish’s health and growth

Idiopathic pulmonary fibrosis: Prognostic value of changes in physiology and six minute hallwalk.

Rationale and Hypothesis: Idiopathic pulmonary fibrosis is a fatal disease with a variable rate of progression. We hypothesized that changes in distance walked and quantity of desaturation during a six-minute-walk test (6MWT) would add prognostic information to changes in FVC or diffusing capacity for carbon monoxide. Methods: One hundred ninety-seven patients with idiopathic pulmonary fibrosis were evaluated. Desaturation during the 6MWT was associated with increased mortality even if a threshold of 88% was not reached. Baseline walk distance predicted subsequent walk distance but was not a reliable predictor of subsequent mortality in multivariate survival models. The predictive ability of serial changes in physiology varied when patients were stratified by the presence/absence of desaturation 88% during a baseline 6MWT. For patients with a baseline saturation 88% during a 6MWT, the strongest observed predictor of mortality was serial change in diffusing capacity for carbon monoxide. For patients with saturation 88% during their baseline walk test, serial decreases in FVC and increases in desaturation area significantly predicted subsequent mortality, whereas decreases in walk distance and in diffusing capacity for carbon monoxide displayed less consistent statistical evidence of increasing mortality in our patients. Conclusion: These data highlight the importance of stratifying patients by degree of desaturation during a 6MWT before attributing prognostic value to serial changes in other physiologic variables.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91940/1/2006 AJRCCM Idiopathic pulmonary fibrosis - Prognostic value of changes in physiology and six minute hallwalk.pd

Prognostic implications of physiologic and radiographic changes in idiopathic interstitial pneumonia

Idiopathic interstitial pneumonias are a diverse group of lung diseases with varied prognoses. We hypothesized that changes in physiologic and radiographic parameters would predict survival. We retrospectively examined 80 patients with usual interstitial pneumonia and 29 patients with nonspecific interstitial pneumonia. Baseline characteristics were examined together with 6-month change in forced vital capacity, diffusing capacity for carbon monoxide, and ground glass infiltrate and fibrosis on high resolution computed tomography. Patients with usual interstitial pneumonia were more likely to have a statistically significant or marginally significant decline in lung volume, diffusing capacity for carbon monoxide, and an increase in ground glass infiltrates (p <= 0.08) compared with patients with nonspecific interstitial pneumonia. For patients with usual interstitial pneumonia, change in forced vital capacity was the best physiologic predictor of mortality (p = 0.05). In a multivariate Cox proportional hazards model controlling for histopathologic diagnosis, gender, smoking history, baseline forced vital capacity, and 6-month change in forced vital capacity, a decrease in forced vital capacity remained an independent risk factor for mortality (decrease > 10%; hazard ratio 2.47; 95% confidence interval 1.29, 4.73; p = 0.006). We conclude that a 6-month change in forced vital capacity gives additional prognostic information to baseline features for patients with idiopathic interstitial pneumonia.Supported by National Institutes of Health NHLBI grants P50HL46487, NIH/NCRR 3 MO1 RR00042-33S3, NIH/NIA P60 AG08808-06, NHLBI, 1 K24 HL04212, and 1 K23 HL68713.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91973/1/2003 AJRCCM - Prognostic Implications of Physiologic and Radiographic Changes in Idiopathic Interstitial Pneumonia.pd