1,134 research outputs found

    Improving Rural Educational Attainment

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    More often than not, policymakers focus on school-based strategies to spur improvements in the educational progress of students. The 2002 No Child Left Behind Act, which demands greater school accountability for student performance, is a case in point. Yet, what happens in the classroom is only part of the story.In fact, as Lionel J. Beaulieu, Glenn D. Israel and Ronald C. Wimberley show in their chapter in "Challenges for Rural America in the Twenty-First Century", family characteristics have from 5 to 10 times as much impact as school characteristics on reading and math scores of rural U.S. eighth graders.In addition, community characteristics have as much impact as school characteristics on test scores, although both community and chool characteristics tend to be more important in geographically isolated rural areas than those adjacent to metropolitan areas. Clearly, helping rural youth succeed academically is the collective responsibility of families, schools, and communities.This issue brief is a joint product of the Rural Sociological Society and the National Coalition for Rural Entrepreneurship, a collaboration of four Regional Rural Development Centers: The Northeast Regional Center for Rural Development, the Southern Rural Development Center, the North Central Regional Center for Rural Development, and the Western Rural Development Center. Funding was also made available from the Ford Foundation.This brief is part of a policy brief series by the Rural Sociological Society and the Regional Rural Development Centers that stresses the importance of community collective action and developing the capacity of people and organizations to meet the community's needsThe Rural Sociological Society and the Regional Rural Development Centers creates new Public Policy Issue Brief series based on its recent book, "Challenges for Rural America in the Twenty-First Century".The briefs synthesize the context and substance of important issues raised in the book and address alternative policy options, with the goal of bringing important research to the policy community

    Validation of an algorithm-based definition of treatment resistance in patients with schizophrenia

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    Large-scale pharmacoepidemiological research on treatment resistance relies on accurate identification of people with treatment-resistant schizophrenia (TRS) based on data that are retrievable from administrative registers. This is usually approached by operationalising clinical treatment guidelines by using prescription and hospital admission information. We examined the accuracy of an algorithm-based definition of TRS based on clozapine prescription and/or meeting algorithm-based eligibility criteria for clozapine against a gold standard definition using case notes. We additionally validated a definition entirely based on clozapine prescription. 139 schizophrenia patients aged 18–65 years were followed for a mean of 5 years after first presentation to psychiatric services in South-London, UK. The diagnostic accuracy of the algorithm-based measure against the gold standard was measured with sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). A total of 45 (32.4%) schizophrenia patients met the criteria for the gold standard definition of TRS; applying the algorithm-based definition to the same cohort led to 44 (31.7%) patients fulfilling criteria for TRS with sensitivity, specificity, PPV and NPV of 62.2%, 83.0%, 63.6% and 82.1%, respectively. The definition based on lifetime clozapine prescription had sensitivity, specificity, PPV and NPV of 40.0%, 94.7%, 78.3% and 76.7%, respectively. Although a perfect definition of TRS cannot be derived from available prescription and hospital registers, these results indicate that researchers can confidently use registries to identify individuals with TRS for research and clinical practices

    International Federation of Clinical Chemistry (IFCC): Scientific Division, Committee on pH, Blood Gases and Electrolytes: Guidelines for Transcutaneouspo2andpco2 Measurement

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    This document provides guidelines for the terminology, methodology, and for the interpretation of data obtained from the use of skin (transcutaneous) po2 and pco2 electrodes. The transcutaneous technique has found special application in newborn infants. The causes of analytical bias with respect to arterial blood gas values, and imprecision obtained with transcutaneous pco2 electrodes, are reviewed. Electrode temperatures above 44°C should not be used routinely, and, at a measuring temperature of 44°C, the measuring site should be changed at least every 4 h to avoid skin burns

    Modelling [18F]LW223 PET data using simplified imaging protocols for quantification of TSPO expression in the rat heart and brain

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    PURPOSE: To provide a comprehensive assessment of the novel 18 kDa translocator protein (TSPO) radiotracer, [(18)F]LW223, kinetics in the heart and brain when using a simplified imaging approach. METHODS: Naive adult rats and rats with surgically induced permanent coronary artery ligation received a bolus intravenous injection of [(18)F]LW223 followed by 120 min PET scanning with arterial blood sampling throughout. Kinetic modelling of PET data was applied to estimated rate constants, total volume of distribution (V(T)) and binding potential transfer corrected (BP(TC)) using arterial or image-derived input function (IDIF). Quantitative bias of simplified protocols using IDIF versus arterial input function (AIF) and stability of kinetic parameters for PET imaging data of different length (40–120 min) were estimated. RESULTS: PET outcome measures estimated using IDIF significantly correlated with those derived with invasive AIF, albeit with an inherent systematic bias. Truncation of the dynamic PET scan duration to less than 100 min reduced the stability of the kinetic modelling outputs. Quantification of [(18)F]LW223 uptake kinetics in the brain and heart required the use of different outcome measures, with BP(TC) more stable in the heart and V(T) more stable in the brain. CONCLUSION: Modelling of [(18)F]LW223 PET showed the use of simplified IDIF is acceptable in the rat and the minimum scan duration for quantification of TSPO expression in rats using kinetic modelling with this radiotracer is 100 min. Carefully assessing kinetic outcome measures when conducting a systems level as oppose to single-organ centric analyses is crucial. This should be taken into account when assessing the emerging role of the TSPO heart-brain axis in the field of PET imaging. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00259-021-05482-1

    Genomics: Think Global, Act Local

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    Long a slogan for environmentalists, “think global, act local” could be a new rallying cry for biologists. As genome-wide techniques advance and their costs drop, scientists are expanding into larger and larger territories—metagenomics, global proteomic approaches, and analyses of thousands of genomes. These massive data sets are opening up new possibilities for understanding some of the smallest details of the genome. Here, we look at four such cases—investigating the evolutionary role of insertions and deletions in the genome, connecting an orphan enzyme with its gene, mapping the fine details of chromatin structure, and characterizing global interactions between proteins and RNA—all of which depend on a combination of global thinking and local action

    Comparing the hierarchy of keywords in on-line news portals

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    The tagging of on-line content with informative keywords is a widespread phenomenon from scientific article repositories through blogs to on-line news portals. In most of the cases, the tags on a given item are free words chosen by the authors independently. Therefore, relations among keywords in a collection of news items is unknown. However, in most cases the topics and concepts described by these keywords are forming a latent hierarchy, with the more general topics and categories at the top, and more specialised ones at the bottom. Here we apply a recent, cooccurrence-based tag hierarchy extraction method to sets of keywords obtained from four different on-line news portals. The resulting hierarchies show substantial differences not just in the topics rendered as important (being at the top of the hierarchy) or of less interest (categorised low in the hierarchy), but also in the underlying network structure. This reveals discrepancies between the plausible keyword association frameworks in the studied news portals

    Hierarchy measure for complex networks

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    Nature, technology and society are full of complexity arising from the intricate web of the interactions among the units of the related systems (e.g., proteins, computers, people). Consequently, one of the most successful recent approaches to capturing the fundamental features of the structure and dynamics of complex systems has been the investigation of the networks associated with the above units (nodes) together with their relations (edges). Most complex systems have an inherently hierarchical organization and, correspondingly, the networks behind them also exhibit hierarchical features. Indeed, several papers have been devoted to describing this essential aspect of networks, however, without resulting in a widely accepted, converging concept concerning the quantitative characterization of the level of their hierarchy. Here we develop an approach and propose a quantity (measure) which is simple enough to be widely applicable, reveals a number of universal features of the organization of real-world networks and, as we demonstrate, is capable of capturing the essential features of the structure and the degree of hierarchy in a complex network. The measure we introduce is based on a generalization of the m-reach centrality, which we first extend to directed/partially directed graphs. Then, we define the global reaching centrality (GRC), which is the difference between the maximum and the average value of the generalized reach centralities over the network. We investigate the behavior of the GRC considering both a synthetic model with an adjustable level of hierarchy and real networks. Results for real networks show that our hierarchy measure is related to the controllability of the given system. We also propose a visualization procedure for large complex networks that can be used to obtain an overall qualitative picture about the nature of their hierarchical structure.Comment: 29 pages, 9 figures, 4 table

    A quantitative PCR method to quantify ruminant DNA in porcine crude heparin

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    Heparin is a well-known glycosaminoglycan extracted from porcine intestines. Increased vigilance for transmissible spongiform encephalopathy in animal-derived pharmaceuticals requires methods to prevent the introduction of heparin from ruminants into the supply chain. The sensitivity, specificity, and precision of the quantitative polymerase chain reaction (PCR) make it a superior analytical platform for screening heparin raw material for bovine-, ovine-, and caprine-derived material. A quantitative PCR probe and primer set homologous to the ruminant Bov-A2 short interspersed nuclear element (SINE) locus (Mendoza-Romero et al. J. Food Prot. 67:550–554, 2004) demonstrated nearly equivalent affinities for bovine, ovine, and caprine DNA targets, while exhibiting no cross-reactivity with porcine DNA in the quantitative PCR method. A second PCR primer and probe set, specific for the porcine PRE1 SINE sequence, was also developed to quantify the background porcine DNA level. DNA extraction and purification was not necessary for analysis of the raw heparin samples, although digestion of the sample with heparinase was employed. The method exhibits a quantitation range of 0.3–3,000 ppm ruminant DNA in heparin. Validation parameters of the method included accuracy, repeatability, precision, specificity, range, quantitation limit, and linearity
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