68 research outputs found

    Economic inequality and student achievement in reading, mathematics, and science across OECD countries

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    In this study, the associations of socioeconomic variables with reading test scores in grade 4 (PIRLS) and with math and science test scores in grades 4 and 8 (TIMSS) were examined across 28 OECD countries. This study adds to the current knowledge base by integrating measures of income inequality, which have been used in a few studies involving test scores, with other socioeconomic variables of interest. Bivariate correlations show that certain socioeconomic measures have stronger relationships with test score inequality than with average test scores: income inequality, gender inequality, and adolescent fertility rates all have significant relationships with test score inequality in reading, math, and science. There are also strong intercorrelations among these three socioeconomic variables. Income inequality is significantly associated with average science test scores in grades 4 and 8, while adolescent fertility rates hold significant relationships with average math and science test scores in both grades. Intercorrelations among the variables show that people who live in a country with high income inequality, and are at the lower end of that country’s income distribution, struggle in ways that people in countries with low income inequality do not. Health insurance and access to health care, paid maternity leave, and preschool education are easier to obtain in countries with lower income inequality. Examination of individual countries gives additional insight into the important role of income inequality. Slovenia, for example, has a relatively low GDP per capita but enjoys good test scores, perhaps because of its low income inequality. Finland, another country with low income inequality, attains PIRLS and TIMSS test scores that are among the highest in the world, in part because of social services that have the effect of further reducing income inequality. The U.S. is something of a puzzle because it has relatively high scores despite substantial inequality. Based on the results of this study and other current research, it seems likely that the U.S. could reduce test score inequality by providing targeted supports to low-income families, effectively reducing income inequality. Such supports may include: 1) installing wraparound services within school settings for low-income families; and 2) substantially expanding preschool access, especially among 3-year-olds

    Long-term culture of intestinal cell progenitors: an overview of their development, application, and associated technologies

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    Purpose of Review Long-term culture of adult progenitor cells in 3D is a recently emerging technology that inhabits the space between 2D cell lines and organ slice culture. Recent Findings Adaptations to defined media components in the wake of advances in ES and iPS cell culture has led to the identification of conditions that maintained intestinal cell progenitors in culture. These conditions retain cellular heterogeneity of the normal or tumour tissue, and the cultures have been shown to be genetically stable, such that substantial biobanks are being created from patient derived material. This coupled with advances in analytical tools has generated a field, characterized by the term “organoid culture”, that has huge potential for advancing drug discovery, regenerative medicine, and furthering the understanding of fundamental intestinal biology. Summary In this review, we describe the approaches available for the long-term culture of intestinal cells from normal and diseased tissue, the current challenges, and how the technology is likely to develop further

    Separating the scales in a compressible interstellar medium

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    We apply Gaussian smoothing to obtain mean density, velocity, magnetic and energy density fields in simulations of the interstellar medium based on three-dimensional magnetohydrodynamic equations in a shearing box 1×1×2kpc1\times1\times2 \, \rm{kpc} in size. Unlike alternative averaging procedures, such as horizontal averaging, Gaussian smoothing retains the three-dimensional structure of the mean fields. Although Gaussian smoothing does not obey the Reynolds rules of averaging, physically meaningful central statistical moments are defined as suggested by Germano (1992). We discuss methods to identify an optimal smoothing scale \ell and the effects of this choice on the results. From spectral analysis of the magnetic, density and velocity fields, we find a suitable smoothing length for all three fields, of 75pc\ell \approx 75 \, \rm{pc}. We discuss the properties of third-order statistical moments in fluctuations of kinetic energy density in compressible flows and suggest their physical interpretation. The mean magnetic field, amplified by a mean-field dynamo, significantly alters the distribution of kinetic energy in space and between scales, reducing the magnitude of kinetic energy at intermediate scales. This intermediate-scale kinetic energy is a useful diagnostic of the importance of SN-driven outflows

    Indoor CO2 and Thermal Conditions in Twenty Scottish Primary School Classrooms with Different Ventilation Systems during the COVID-19 Pandemic

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    Healthy indoor environments influence the comfort, health and wellbeing of the occupants. Monitoring the indoor temperature, relative humidity and CO2 levels in primary schools during the COVID-19 pandemic was mandated by a local authority in Scotland. The aim was to investigate the comfort and safety of the teachers and their pupils. This paper presents the measurements of indoor climate in 20 classrooms in four different primary schools in Scotland. The schools were of different architypes. The classrooms were of different sizes, orientations and occupancy, and had different ventilation systems. Ventilation was achieved either by manually opening the windows, or by a mechanical ventilation system. Indoor air temperature, relative humidity and carbon dioxide (CO2) concentrations were continuously monitored for one week during the heating season 2020/21. Occupancy and opening of the windows were logged in by the teachers. The ventilation rates in the classrooms were estimated by measuring the CO2 concentrations. On the 20 classrooms of the study, data of 19 were analysed. The results show that four of the five mechan-ically ventilated classrooms performed better than natural ventilation, which indicates that opening the windows depended on the customs and habits. Classrooms in naturally ventilated Victorian buildings have the worst average ventilation rate (4.38 L/s per person) compared to the other classrooms (5.8 L/s per person for the more recent naturally ventilated ones, and 6.08 L/s per person for the mechanically ventilated ones). The results of this preliminary study will be used as the basis to find ways to ensure adequate ventilation in natural ventilated classrooms

    First-principles extrapolation method for accurate CO adsorption energies on metal surfaces

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    We show that a simple first-principles correction based on the difference between the singlet-triplet CO excitation energy values obtained by DFT and high-level quantum chemistry methods yields accurate CO adsorption properties on a variety of metal surfaces. We demonstrate a linear relationship between the CO adsorption energy and the CO singlet-triplet splitting, similar to the linear dependence of CO adsorption energy on the energy of the CO 2π\pi* orbital found recently {[Kresse {\em et al.}, Physical Review B {\bf 68}, 073401 (2003)]}. Converged DFT calculations underestimate the CO singlet-triplet excitation energy ΔEST\Delta E_{\rm S-T}, whereas coupled-cluster and CI calculations reproduce the experimental ΔEST\Delta E_{\rm S-T}. The dependence of EchemE_{\rm chem} on ΔEST\Delta E_{\rm S-T} is used to extrapolate EchemE_{\rm chem} for the top, bridge and hollow sites for the (100) and (111) surfaces of Pt, Rh, Pd and Cu to the values that correspond to the coupled-cluster and CI ΔEST\Delta E_{\rm S-T} value. The correction reproduces experimental adsorption site preference for all cases and obtains EchemE_{\rm chem} in excellent agreement with experimental results.Comment: Table sent as table1.eps. 3 figure

    3D imaging of colorectal cancer organoids identifies responses to Tankyrase inhibitors

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    Aberrant activation of the Wnt signalling pathway is required for tumour initiation and survival in the majority of colorectal cancers. The development of inhibitors of Wnt signalling has been the focus of multiple drug discovery programs targeting colorectal cancer and other malignancies associated with aberrant pathway activation. However, progression of new clinical entities targeting the Wnt pathway has been slow. One challenge lies with the limited predictive power of 2D cancer cell lines because they fail to fully recapitulate intratumoural phenotypic heterogeneity. In particular, the relationship between 2D cancer cell biology and cancer stem cell function is poorly understood. By contrast, 3D tumour organoids provide a platform in which complex cell-cell interactions can be studied. However, complex 3D models provide a challenging platform for the quantitative analysis of drug responses of therapies that have differential effects on tumour cell subpopulations. Here, we generated tumour organoids from colorectal cancer patients and tested their responses to inhibitors of Tankyrase (TNKSi) which are known to modulate Wnt signalling. Using compounds with 3 orders of magnitude difference in cellular mechanistic potency together with image-based assays, we demonstrate that morphometric analyses can capture subtle alterations in organoid responses to Wnt inhibitors that are consistent with activity against a cancer stem cell subpopulation. Overall our study highlights the value of phenotypic readouts as a quantitative method to asses drug-induced effects in a relevant preclinical model

    Modeling colorectal cancer: A bio-resource of 50 patient-derived organoid lines

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    Background and Aim Colorectal cancer (CRC) is the second leading cause of cancer death worldwide. To improve outcomes for these patients, we need to develop new treatment strategies. Personalized cancer medicine, where patients are treated based on the characteristics of their own tumor, has gained significant interest for its promise to improve outcomes and reduce unnecessary side effects. The purpose of this study was to examine the potential utility of patient-derived colorectal cancer organoids (PDCOs) in a personalized cancer medicine setting. Methods Patient-derived colorectal cancer organoids were derived from tissue obtained from treatment-naïve patients undergoing surgical resection for the treatment of CRC. We examined the recapitulation of key histopathological, molecular, and phenotypic characteristics of the primary tumor. Results We created a bio-resource of PDCOs from primary and metastatic CRCs. Key histopathological features were retained in PDCOs when compared with the primary tumor. Additionally, a cohort of 12 PDCOs, and their corresponding primary tumors and normal sample, were characterized through whole exome sequencing and somatic variant calling. These PDCOs exhibited a high level of concordance in key driver mutations when compared with the primary tumor. Conclusions Patient-derived colorectal cancer organoids recapitulate characteristics of the tissue from which they are derived and are a powerful tool for cancer research. Further research will determine their utility for predicting patient outcomes in a personalized cancer medicine setting

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

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    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Supplement A- Supplemental material for "Role of PT in Ventral Hernia Reconstruction"

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    Supplement A- Supplemental material for "Role of PT in Ventral Hernia Reconstruction"</p
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