School Size and the Distribution of Test Scores

After forty years of school consolidation, the preponderance of the evidence, including the results presented in this paper, suggest that the race to reap returns to scale and specialization in education may have come at a high price. This paper uses newly available STAR test score data from California to explore the relationship between school size and the distribution of test scores across elementary, middle, and high schools. We find that school size has a statistically significant and economically large impact on school performance. For example, the probability that an average suburban high school is dominated by low scorers rises from 47% to 71% as the school grows from 200 to 800 students per grade.school size, test scores

Tiltaksplan for forurensede sedimenter i Aust-Agder. Fase 1 - Miljøtilstand,

Rapporten omhandler første fase av tiltaksplan for forurensede sedimenter i Aust-Agder. De tre utvalgte områdene i Aust-Agder er Tvedestrand på innsiden av Sagesund, Arendal havneområde med Tromøysund og Vikkilen i Grimstad. I dette arbeidet er det gjort en gjennomgang av eksisterende data med kartpresentasjon av miljøstatus for de ulike miljøgiftene i hvert tiltaksområde. Videre er det gitt en oversikt over aktuelle og mulige kilder til forurensning i nedbørfeltet og høyrisikoområder er foreslått. Data fra indre Tvedestrandsfjord har vist høye konsentrasjoner av både PAH og TBT (tilstandsklasse IV-V) slik at flere grunne områder er definert som mulige høyrisikoområder. Det er imidlertid behov for å ta prøver i grunne farvann for å kunne fastslå dette. I Arendal er spesielt havneområdene og området rundt Eydehavn forurenset av miljøgifter, men også småbåthavner og andre områder er sterkt forurenset. I likhet med Tvedestrand er det også her lite data fra grunne områder som er mest utsatt for spredning. Indre del av Vikkilen er foreslått som høyrisikoområde på grunn av høye PAH-verdier og ekstremt høye TBT-verdier. Det er behov for å ta prøver som verifiserer nivåene og gir opplysning om omfang

Corporate philanthropic practices

We study corporate philanthropy using an original database that includes firm-level data on dollar giving, giving priorities, governance, and managerial involvement in giving programs. Results provide some support for the theory that giving enhances shareholder value, as firms in the same industry tend to adopt similar giving practices and firms that advertise more intensively also give more to charity. But much of our evidence indicates that agency costs play a prominent role in explaining corporate giving. Firms with larger boards of directors are associated with significantly more cash giving and with the establishment of corporate foundations. Consistent with effective monitoring by creditors, firms with higher debt-to-value ratios give less cash to charities and are less likely to establish foundations. The empirical work considers the impact of industry regulation on giving and controls for state philanthropy laws and fiduciary responsibility laws

On the estimation of CO2 capillary entry pressure : Implications on geological CO2 storage

This work was partially funded by the Research Council of Norway through a CLIMIT project, ConocoPhillips and the Ekofisk co-venturers, including TOTAL, ENI, Statoil and Petoro. We thank the anonymous reviewers whose comments/suggestions helped to improve the written presentation of this manuscript.Peer reviewedPostprin

Ecological speciation in European whitefish is driven by a large-gaped predator

Lake-dwelling fish that form species pairs/flocks characterized by body size divergence are important model systems for speciation research. Although several sources of divergent selection have been identified in these systems, their importance for driving the speciation process remains elusive. A major problem is that in retrospect, we cannot distinguish selection pressures that initiated divergence from those acting later in the process. To address this issue, we studied the initial stages of speciation in European whitefish (Coregonus lavaretus) using data from 358 populations of varying age (26-10,000 years). We find that whitefish speciation is driven by a large-growing predator, the northern pike (Esox lucius). Pike initiates divergence by causing a largely plastic differentiation into benthic giants and pelagic dwarfs: ecotypes that will subsequently develop partial reproductive isolation and heritable differences in gill raker number. Using an eco-evolutionary model, we demonstrate how pike's habitat specificity and large gape size are critical for imposing a between-habitat trade-off, causing prey to mature in a safer place or at a safer size. Thereby, we propose a novel mechanism for how predators may cause dwarf/giant speciation in lake-dwelling fish species.Peer reviewe

Segmentation of glioblastomas in early post-operative multi-modal MRI with deep neural networks

Extent of resection after surgery is one of the main prognostic factors for patients diagnosed with glioblastoma. To achieve this, accurate segmentation and classification of residual tumor from post-operative MR images is essential. The current standard method for estimating it is subject to high inter- and intra-rater variability, and an automated method for segmentation of residual tumor in early post-operative MRI could lead to a more accurate estimation of extent of resection. In this study, two state-of-the-art neural network architectures for pre-operative segmentation were trained for the task. The models were extensively validated on a multicenter dataset with nearly 1000 patients, from 12 hospitals in Europe and the United States. The best performance achieved was a 61% Dice score, and the best classification performance was about 80% balanced accuracy, with a demonstrated ability to generalize across hospitals. In addition, the segmentation performance of the best models was on par with human expert raters. The predicted segmentations can be used to accurately classify the patients into those with residual tumor, and those with gross total resection

Quantification of resting myocardial blood flow velocity in normal humans using real-time contrast echocardiography. A feasibility study

BACKGROUND: Real-time myocardial contrast echocardiography (MCE) is a novel method for assessing myocardial perfusion. The aim of this study was to evaluate the feasibility of a very low-power real-time MCE for quantification of regional resting myocardial blood flow (MBF) velocity in normal human myocardium. METHODS: Twenty study subjects with normal left ventricular (LV) wall motion and normal coronary arteries, underwent low-power real-time MCE based on color-coded pulse inversion Doppler. Standard apical LV views were acquired during constant IV. infusion of SonoVue(®). Following transient microbubble destruction, the contrast replenishment rate (β), reflecting MBF velocity, was derived by plotting signal intensity vs. time and fitting data to the exponential function; y (t) =A (1-e(-β(t-t0))) + C. RESULTS: Quantification was feasible in 82%, 49% and 63% of four-chamber, two-chamber and apical long-axis view segments, respectively. The LAD (left anterior descending artery) and RCA (right coronary artery) territories could potentially be evaluated in most, but contrast detection in the LCx (left circumflex artery) bed was poor. Depending on localisation and which frames to be analysed, mean values of [Image: see text] were 0.21–0.69 s(-1), with higher values in medial than lateral, and in basal compared to apical regions of scan plane (p = 0.03 and p < 0.01). Higher β-values were obtained from end-diastole than end-systole (p < 0.001), values from all-frames analysis lying between. CONCLUSION: Low-power real-time MCE did have the potential to give contrast enhancement for quantification of resting regional MBF velocity. However, the technique is difficult and subjected to several limitations. Significant variability in β suggests that this parameter is best suited for with-in patient changes, comparing values of stress studies to baseline

Associations between maternal long-chain polyunsaturated fatty acid concentrations and child cognition at 7 years of age: The MEFAB birth cohort

Concentrations of the fish fatty acids EPA and DHA are low among Dutch women of reproductive age. As the human brain incorporates high concentrations of these fatty acids in utero, particularly during third trimester of gestation, these low EPA and DHA concentrations may have adverse consequences for fetal brain development and functioning. Analyses were conducted using longitudinal observational data of 292 mother-child pairs participating in the MEFAB cohort. Maternal AA, DHA, and EPA were determined in plasma phospholipids - obtained in three trimesters - by gas-liquid chromatography. Cognitive function was assessed at 7 years of age, using the Kaufman Assessment Battery for Children, resulting in three main outcome parameters: sequential processing (short-term memory), simultaneous processing (problem-solving skills), and the mental processing composite score. Spline regression and linear regression analyses were used to analyse the data, while adjusting for potential relevant covariates. Only 2% of the children performed more than one SD below the mental processing composite norm score. Children with lower test scores (<25%) were more likely to have a younger mother with a higher pre-gestational BMI, less likely to be breastfed, and more likely to be born with a lower birth weight, compared to children with higher test scores (≥25%). Fully-adjusted linear regression models did not show associations of maternal AA, DHA, or EPA status during any of the pregnancy trimesters with childhood sequential and simultaneous processing. Maternal fatty acid status during pregnancy was not associated with cognitive performance in Dutch children at age 7

Myalgic encephalomyelitis/chronic fatigue Syndrome (ME/CFS) : Investigating care practices pointed out to disparities in diagnosis and treatment across European Union

ME/CFS is a chronic, complex, multisystem disease that often limits the health and functioning of the affected patients. Diagnosing patients with ME/CFS is a challenge, and many different case definitions exist and are used in clinical practice and research. Even after diagnosis, medical treatment is very challenging. Symptom relief and coping may affect how patients live with their disease and their quality of life. There is no consensus on which diagnostic criteria should be used and which treatment strategies can be recommended for patients. The purpose of the current project was to map the landscape of the Euromene countries in respect of national guidelines and recommendations for case definition, diagnosis and clinical approaches for ME/CFS patients. A 23 items questionnaire was sent out by email to the members of Euromene. The form contained questions on existing guidelines for case definitions, treatment/management of the disease, tests and questionnaires applied, and the prioritization of information for data sampling in research. We obtained information from 17 countries. Five countries reported having national guidelines for diagnosis, and five countries reported having guidelines for clinical approaches. For diagnostic purposes, the Fukuda criteria were most often recommended, and also the Canadian Consensus criteria, the International Consensus Criteria and the Oxford criteria were used. A mix of diagnostic criteria was applied within those countries having no guidelines. Many different questionnaires and tests were used for symptom registration and diagnostic investigation. For symptom relief, pain and anti-depressive medication were most often recommended. Cognitive Behavioral Therapy and Graded Exercise treatment were often recommended as disease management and rehabilitative/palliative strategies. The lack of consistency in recommendations across European countries urges the development of regulations, guidance and standards. The results of this study will contribute to the harmonization of diagnostic criteria and treatment for ME/CFS in Europe