999 research outputs found
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Who benefits from public spending on higher education in South Asia and sub-Saharan Africa?
Most countries are far from achieving the new sustainable development target of equal access to higher education by 2030, with those in South Asia and sub-Saharan Africa furthest behind. This raises questions about the allocation of public resources across the education system to promote equity. We use data from Demographic and Health Surveys and UNESCO Institute for Statistics in 31 countries in these regions to assess who benefits from public spending on education. Our results reveal an overall pattern of pro-rich education spending, increasing with education level. We find that this pattern can be traced to an allocation of resources to higher education that is disproportionate to the sub-sectorâs size: even when higher education spending overall represents a small proportion of total educational expenditure, per-capita expenditure is extremely high. Given that the richest predominantly gain access to higher education, the current spending patterns are likely to reinforce wealth-driven education inequalities
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Understanding the external social benefits of education in Ethiopia: A contextual analysis using young lives
This paper explores social benefits, or externalities, of education in Ethiopia. Enrolment has expanded rapidly across all phases of formal education, yet there is limited evidence of its potential externalities in this context. This paper draws on the Young Lives study which provides longitudinal data on the lives of children over the past two decades. Using data from Young Livesâ older cohort of survey respondents, our results show that young people who participated in education beyond secondary level were more likely to engage in community action and to voluntarily give to community organizations or political groups than young people with lower levels of education. These results show the potential externalities of education. Importantly, the paper situates empirical analyses and results in the socio-cultural realities within and beyond the education sector in Ethiopia. The paper thus provides a deeper and contextually relevant understanding for the existence of social benefits and the potential enhancement of these through formal education
Force and energy dissipation variations in non-contact atomic force spectroscopy on composite carbon nanotube systems
UHV dynamic force and energy dissipation spectroscopy in non-contact atomic
force microscopy were used to probe specific interactions with composite
systems formed by encapsulating inorganic compounds inside single-walled carbon
nanotubes. It is found that forces due to nano-scale van der Waals interaction
can be made to decrease by combining an Ag core and a carbon nanotube shell in
the Ag@SWNT system. This specific behaviour was attributed to a significantly
different effective dielectric function compared to the individual
constituents, evaluated using a simple core-shell optical model. Energy
dissipation measurements showed that by filling dissipation increases,
explained here by softening of C-C bonds resulting in a more deformable
nanotube cage. Thus, filled and unfilled nanotubes can be discriminated based
on force and dissipation measurements. These findings have two different
implications for potential applications: tuning the effective optical
properties and tuning the interaction force for molecular absorption by
appropriately choosing the filling with respect to the nanotube.Comment: 22 pages, 6 figure
Seeds for effective oligonucleotide design
Background: DNA oligonucleotides are a very useful tool in biology. The best algorithms for designing good DNA oligonucleotides are filtering out unsuitable regions using a seeding approach. Determining the quality of the seeds is crucial for the performance of these algorithms.\ud
Results: We present a sound framework for evaluating the quality of seeds for oligonucleotide design. The F-score is used to measure the accuracy of each seed. A number of natural candidates are tested: contiguous (BLAST-like), spaced, transitions-constrained, and multiple spaced seeds. Multiple spaced seeds are the best, with more seeds providing better accuracy. Single spaced and transition seeds are very close whereas, as expected, contiguous seeds come last. Increased accuracy comes at the price of reduced efficiency. An exception is that single spaced and transitions-constrained seeds are both more accurate and more efficient than contiguous ones.\ud
Conclusions: Our work confirms another application where multiple spaced seeds perform the best. It will be useful in improving the algorithms for oligonucleotide desig
Testing the magnetotail configuration based on observations of lowâaltitude isotropic boundaries during quiet times
We investigate the configuration of the geomagnetic field on the nightside magnetosphere during a quiet time interval based on National Oceanic and Atmospheric Administration Polar Orbiting Environment Satellites Medium Energy Proton and Electron Detector (NOAA/POES MEPED) measurements in combination with numerical simulations of the global terrestrial magnetosphere using the Space Weather Modeling Framework. Measurements from the NOAA/POES MEPED lowâaltitude data sets provide the locations of isotropic boundaries; those are used to extract information regarding the field structure in the source regions in the magnetosphere. In order to evaluate adiabaticity and mapping accuracy, which is mainly controlled by the ratio between the radius of curvature and the particleâs Larmor radius, we tested the threshold condition for strong pitch angle scattering based on the MHD magnetic field solution. The magnetic field configuration is represented by the model with high accuracy, as suggested by the high correlation coefficients and very low normalized rootâmeanâsquare errors between the observed and the modeled magnetic field. The scattering criterion, based on the values of k=RcÏ ratio at the crossings of magnetic field lines, associated with isotropic boundaries, with the minimum B surface, predicts a critical value of kCRâŒ33. This means that, in the absence of other scattering mechanisms, the strong pitch angle scattering takes place whenever the Larmor radius is âŒ33 times smaller than the radius of curvature of the magnetic field, as predicted by the Space Weather Modeling Framework.Key PointsWe tested the threshold condition for strong pitch angle scattering based on the MHD magnetic fieldSWMF model suggests a threshold condition for strong pitch angle scattering of k = 33For quiet time, the k parameter varies within 2 orders of magnitudePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135070/1/jgra52310.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135070/2/jgra52310_am.pd
On Maximal Unbordered Factors
Given a string of length , its maximal unbordered factor is the
longest factor which does not have a border. In this work we investigate the
relationship between and the length of the maximal unbordered factor of
. We prove that for the alphabet of size the expected length
of the maximal unbordered factor of a string of length~ is at least
(for sufficiently large values of ). As an application of this result, we
propose a new algorithm for computing the maximal unbordered factor of a
string.Comment: Accepted to the 26th Annual Symposium on Combinatorial Pattern
Matching (CPM 2015
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A research-informed dialogic-teaching approach to early secondary school mathematics and science: the pedagogical design and field trial of the epiSTEMe intervention
The project undertook pedagogical research aimed at improving pupil engagement and learning in early secondary school physical science and mathematics. Using principles identified as effective in the research literature and drawing on a range of existing pedagogical resources, the project designed and trialled a classroom intervention, with associated professional development, in a form intended to be suited to implementation at scale. The most distinctive feature of the pedagogical approach is its inclusion of a component of dialogic teaching. Aimed at the first year of secondary education in English schools (covering ages 11â12), the intervention consists of a short introductory module designed to prepare classes for this dialogic teaching component, and topic modules which employ the pedagogical approach to cover two curricular topics in each of science and mathematics. A field trial was conducted over the 2010/2011 school year in 25 volunteer schools, randomly assigned to intervention and control groups. Within the intervention group, observation of lessons indicated that the level of dialogic teaching was higher for one of the topic modules than others. Evaluation focused on the effectiveness of the topic modules, each trialled in more than 10 classes containing a total of over 300 pupils, and compared with a group of similar composition. Overall, at this first implementation, learning gains under the intervention were no greater, although for individual topic modules the effects ranged from small negative to small positive. No difference was found between intervention and control groups either in the opinion of pupils about their classroom experience or in changes in their attitude towards subjects.Thanks are due to the Economic and Social Research Council which provided funding for the epiSTEMe project (RES-179-25-0003), to the teachers who generously volunteered to review, pilot and trial versions of the modules, to Christine Howe for her contribution to design and analysis, and to Andy Tolmie and Anna Vignoles for statistical advice.This is the final version of the article. It first appeared from Taylor & Francis via https://doi.org/10.1080/02671522.2015.112964
Finding All Solutions of Equations in Free Groups and Monoids with Involution
The aim of this paper is to present a PSPACE algorithm which yields a finite
graph of exponential size and which describes the set of all solutions of
equations in free groups as well as the set of all solutions of equations in
free monoids with involution in the presence of rational constraints. This
became possible due to the recently invented emph{recompression} technique of
the second author.
He successfully applied the recompression technique for pure word equations
without involution or rational constraints. In particular, his method could not
be used as a black box for free groups (even without rational constraints).
Actually, the presence of an involution (inverse elements) and rational
constraints complicates the situation and some additional analysis is
necessary. Still, the recompression technique is general enough to accommodate
both extensions. In the end, it simplifies proofs that solving word equations
is in PSPACE (Plandowski 1999) and the corresponding result for equations in
free groups with rational constraints (Diekert, Hagenah and Gutierrez 2001). As
a byproduct we obtain a direct proof that it is decidable in PSPACE whether or
not the solution set is finite.Comment: A preliminary version of this paper was presented as an invited talk
at CSR 2014 in Moscow, June 7 - 11, 201
Assessing the role of oxygen on ring current formation and evolution through numerical experiments
We address the effect of ionospheric outflow and magnetospheric ion composition on the physical processes that control the development of the 5 August 2011 magnetic storm. Simulations with the Space Weather Modeling Framework are used to investigate the global dynamics and energization of ions throughout the magnetosphere during storm time, with a focus on the formation and evolution of the ring current. Simulations involving multifluid (with variable H+/O+ ratio in the inner magnetosphere) and singleâfluid (with constant H+/O+ ratio in the inner magnetosphere) MHD for the global magnetosphere with inner boundary conditions set either by specifying a constant ion density or by physicsâbased calculations of the ion fluxes reveal that dynamical changes of the ion composition in the inner magnetosphere alter the total energy density of the magnetosphere, leading to variations in the magnetic field as well as particle drifts throughout the simulated domain. A low oxygen to hydrogen ratio and outflow resulting from a constant ion density boundary produced the most disturbed magnetosphere, leading to a stronger ring current but misses the timing of the storm development. Conversely, including a physicsâbased solution for the ionospheric outflow to the magnetosphere system leads to a reduction in the crossâpolar cap potential (CPCP). The increased presence of oxygen in the inner magnetosphere affects the global magnetospheric structure and dynamics and brings the nightside reconnection point closer to the Earth. The combination of reduced CPCP together with the formation of the reconnection line closer to the Earth yields less adiabatic heating in the magnetotail and reduces the amount of energetic plasma that has access to the inner magnetosphere.Key PointsLow O+/H+ ratio produced stronger ring currentInclusion of physicsâbased ionospheric outflow leads to a reduction in the CPCPOxygen presence is linked to a nightside reconnection point closer to the EarthPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112251/1/jgra51856.pd
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