Factors associated with private-public school performance: analysis of TALIS-PISA link data

We use measures of competitive pressure, administrative autonomy and staffing practices to explain the private-public performance difference in Australia, Portugal and Spain using the TALIS-PISA dataset. We employ OLS regression and counterfactual decomposition analysis on matched sub-samples. These school factors do not explain the overall private-public performance gap in the three countries except at the higher-end of the distribution. In other words, these factors appear to benefit only the high-performers in private schools in Australia and Spain. The results point to the potential limits of adopting private school practices for improving learning across the performance distribution especially for low-performing students

A promessa não aproveitada do uso de dados secundários na investigação internacional e comparada das políticas educativas

The objective of this commentary is to call attention to the feasibility and importance of large-scale, systematic, quantitative analysis in international and comparative education research. We contend that although many existing databases are under- or unutilized in quantitative international-comparative research, these resources present the opportunity for important, policy-relevant descriptive studies. We conclude the commentary with overarching observations about the strengths and limitations of such secondary data-based analysis.El objetivo de este comentario es señalar la viabilidad y la importancia del análisis cuantitativo, sistemático, y a gran escala en la investigación de la educación comparada internacional. Sostenemos que aunque muchas bases de datos existentes están poco o no utilizados en la investigación internacional y comparativa cuantitativa, estos recursos tienen mucho potencial para hacer estudios descriptivos importantes y relevantes para la política. Concluimos el comentario con observaciones generales sobre las ventajas y las desventajas de análisis basado en datos secundarios. O objetivo deste comentário é destacar a viabilidade e a importância das análise quantitativa, sistemática e investigação em grande escala na educação comparada internacional. Argumentamos que, enquanto muitos bancos de dados existentes são pouco ou não utilizados na investigação internacional e comparada quantitativa, esses recursos têm um grande potencial para estudos descritivos importantes e relevantes para as políticas. Nós concluímos o comentário com observações gerais sobre as vantagens e desvantagens de análise com base em dados secundários

Learning to add: are we subtracting the importance of the home environment?

Since my early days in school my association with Mathematics in most of its forms, including Algebra, geometry, and Statistics has always been very pleasant. In fact, Geometry, followed by Physics, was my favourite subject in school. Admittedly, there were some rough patches but right now they all seem too insignificant to even mention. To this day, I continue my healthy association with Math that I formed when I was young. A vast amount of my work today depends on applied quantitative research and I must say that on most days I can't get enough of it

Preparation and characterization of bis-[1,3,5]triazinyl diazenes and their utilization as flame retardants in polypropylene films

A series of bis-[1,3,5]triazinyl diazenes and two metal complexes thereof were synthesized and tested as new flame retardants in polypropylene films. It was observed that electron withdrawing triazinyl ring substituents (i.e. Cl and phenyl moieties) improved the thermal stability of diazene compounds, whereas electron donating groups (i.e. methoxy, dimethylamino and ethylthio moieties) had a destabilizing effect. TGA, DTA/DSC, NMR and ATR-FTIR were used for the characterization. Quantum mechanical modeling (Gaussian 09) was also utilized to facilitate the interpretation of the NMR data. Bis-(4,6-dichloro-[1,3,5]triazin-2-yl)-diazene 1 and bis-(4,6-dimethoxy-[1,3,5]triazin-2-yl)-diazene 2 were found to be effective flame retardants in polypropylene films and DIN4102-1 B2 classification was reached already at a loading of 0.5 wt%. Interestingly, the copper complex of 2 showed even higher fire retardant activity than its precursor 2, whereas the corresponding zinc complex exhibited lower flame retardant efficacy than its precursor

OASIS is Automated Statistical Inference for Segmentation, with applications to multiple sclerosis lesion segmentation in MRI☆

Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78%]) and the radiologist 52% (95% CI: [38%, 66%]). OASIS obtains the estimated probability for each voxel to be part of a lesion by weighting each imaging modality with coefficient weights. These coefficients are explicit, obtained using standard model fitting techniques, and can be reused in other imaging studies. This fully automated method allows sensitive and specific detection of lesion presence and may be rapidly applied to large collections of images

Gold catalysts for the synthesis of aromatic azocompounds from nitroaromatics in one step

[EN] One-step selective hydrogenation of nitroaromatics to obtain symmetric azocompounds with high yields has been performed with a gold supported on cerium oxide catalysts. Au/TiO2 and Au/CeO2 catalysts direct the reaction by two different pathways and with different selectivities. In situ FTIR studies reveal that the surface concentration of the intermediate nitrosobenzene is decisive in directing the reaction trough the different reaction pathways. In this way, while on Au/TiO2 a fast hydrogenation of the nitrosobenzene intermediate leads to a low surface concentration of the nitrosocompound, on Au/CeO2 nitrosobenzene is more stabilized on the catalyst surface leading to a lower hydrogenation and a higher coupling rate, resulting in high selectivities to azobenzene. On Au/CeO2, the relative weak adsorption of the azo with respect to the azoxycompound on the catalyst surface avoids the consecutive hydrogenation of azocompounds to the corresponding anilines until all the azoxy has been consumed. Asymmetric azobenzenes have also been obtained with very high yields on TiO2, through the Mills reaction.The authors wish to acknowledge the financial support from the Spanish Ministries of Education and Science and Economy and Competitiveness under the project Consolider-Ingenio 2010 (CSD2009-00050 "Development of more efficient catalysts for the design of sustainable chemical processes and clean energy production") and the Severo Ochoa program (SEV-2012-0267), respectively. D.C. thanks the Spanish MEC for postgraduate scholarship, project MAT2006-14274-C02-01.Cómbita Merchán, DF.; Concepción Heydorn, P.; Corma Canós, A. (2014). Gold catalysts for the synthesis of aromatic azocompounds from nitroaromatics in one step. Journal of Catalysis. 311:339-349. https://doi.org/10.1016/j.jcat.2013.12.014S33934931

Aspergillus niger: an unusual cause of invasive pulmonary aspergillosis

Infections due to Aspergillus species cause significant morbidity and mortality. Most are attributed to Aspergillus fumigatus, followed by Aspergillus flavus and Aspergillus terreus. Aspergillus niger is a mould that is rarely reported as a cause of pneumonia. A 72-year-old female with chronic obstructive pulmonary disease and temporal arteritis being treated with steroids long term presented with haemoptysis and pleuritic chest pain. Chest radiography revealed areas of heterogeneous consolidation with cavitation in the right upper lobe of the lung. Induced bacterial sputum cultures, and acid-fast smears and cultures were negative. Fungal sputum cultures grew A. niger. The patient clinically improved on a combination therapy of empiric antibacterials and voriconazole, followed by voriconazole monotherapy. After 4 weeks of voriconazole therapy, however, repeat chest computed tomography scanning showed a significant progression of the infection and near-complete necrosis of the right upper lobe of the lung. Serum voriconazole levels were low–normal (1.0 μg ml−1, normal range for the assay 0.5–6.0 μg ml−1). A. niger was again recovered from bronchoalveolar lavage specimens. A right upper lobectomy was performed, and lung tissue cultures grew A. niger. Furthermore, the lung histopathology showed acute and organizing pneumonia, fungal hyphae and oxalate crystallosis, confirming the diagnosis of invasive A. niger infection. A. niger, unlike A. fumigatus and A. flavus, is less commonly considered a cause of invasive aspergillosis (IA). The finding of calcium oxalate crystals in histopathology specimens is classic for A. niger infection and can be helpful in making a diagnosis even in the absence of conidia. Therapeutic drug monitoring may be useful in optimizing the treatment of IA given the wide variations in the oral bioavailability of voriconazole

Women, weather, and woes: The triangular dynamics of female-headed households, economic vulnerability, and climate variability in South Africa

Existing gender inequality is believed to be heightened as a result of weather events and climate-related disasters that are likely to become more common in the future. We show that an already marginalized group—female-headed households in South Africa—is differentially affected by relatively modest levels of variation in rainfall, which households experience on a year-to-year basis. Data from three waves of the National Income Dynamics Survey in South Africa allow us to follow incomes of 4,162 households from 2006 to 2012. By observing how household income is affected by variation in rainfall relative to what is normally experienced during the rainy season in each district, our study employs a series of naturally occurring experiments that allow us to identify causal effects. We find that households where a single head can be identified based on residency or work status are more vulnerable to climate variability than households headed by two adults. Single male-headed households are more vulnerable because of lower initial earnings and, to a lesser extent, other household characteristics that contribute to economic disadvantages. However, this can only explain some of the differential vulnerability of female-headed households. This suggests that there are traits specific to female-headed households, such as limited access to protective social networks or other coping strategies, which makes this an important dimension of marginalization to consider for further research and policy in South Africa and other national contexts. Households headed by widows, never-married women, and women with a non-resident spouse (e.g., “left-behind” migrant households) are particularly vulnerable. We find vulnerable households only in districts where rainfall has a large effect on agricultural yields, and female-headed households remain vulnerable when accounting for dynamic impacts of rainfall on income

Gender Based Within-Household Inequality in Childhood Immunization in India: Changes over Time and across Regions

Background and Objectives: Despite India’s substantial economic growth in the past two decades, girls in India are discriminated against in access to preventive healthcare including immunizations. Surprisingly, no study has assessed the contribution of gender based within-household discrimination to the overall inequality in immunization status of Indian children. This study therefore has two objectives: to estimate the gender based within-household inequality (GWHI) in immunization status of Indian children and to examine the inter-regional and inter-temporal variations in the GWHI. Data and Methods: The present study used households with a pair of male-female siblings (aged 1–5 years) from two rounds of National Family Health Survey (NFHS, 1992–93 and 2005–06). The overall inequality in the immunization status (after controlling for age and birth order) of children was decomposed into within-households and between-households components using Mean log deviation to obtain the GWHI component. The analysis was conducted at the all-India level as well as for six specified geographical regions and at two time points (1992–93 and 2005–06). Household fixed-effects models for immunization status of children were also estimated. Results and Conclusions: Findings from household fixed effects analysis indicated that the immunization scores of girls were significantly lower than that of boys. The inequality decompositions revealed that, at the all-India level, the absolute level of GWHI in immunization status decreased from 0.035 in 1992–93 to 0.023 in 2005–06. However, as a percentage o