77 research outputs found
Child Language Brokering in School: Final Research Report
The primary aim of the project was to provide an evidence basis for more sensitive and effective practice and more carefully articulated school policies on the use of pupils as language brokers for their own parents and others in school. To this end we investigated and triangulated the views and experiences of two groups who we expected to bring distinctive and complementary perspectives to the topic - teachers in schools in multilingual areas and young adults who had acted as language brokers in the course of their own school career (ex-CLBs ). The study addressed the following research questions in relation to both groups: 1. How often and for what purposes are CLBs used in schools? 2. To what degree are CLBs used in routine contacts with parents (their own & those of others), in more sensitive discussions about vulnerable pupils (e.g. about SEN) and in discussions when crucial matters are being resolved (e.g. planning for subject choices in Year 10)? 3. What are the perceived advantages and disadvantages of school language brokering arrangements? 4. How do teachers and ex-CLBs perceive CLBs in terms of their alignment with family or personal interests as against detached, independent values of translation and interpreting? 5. What views do ex-CLBs now have of their experience of the process, their own agency, competence and effectiveness and how the process was facilitated or obstructed by the actions and attitudes of their teachers? 6. What differences of view and understanding are there between teachers who are themselves bilingual or multilingual, teachers who are monolingual and ex-CLBs? 7. What recommendations would current teachers and ex-CLBs make on how to improve schools? policies and practices on CLB activity
Child Language Brokering in School: Final Research Report
The primary aim of the project was to provide an evidence basis for more sensitive and effective practice and more carefully articulated school policies on the use of pupils as language brokers for their own parents and others in school. To this end we investigated and triangulated the views and experiences of two groups who we expected to bring distinctive and complementary perspectives to the topic - teachers in schools in multilingual areas and young adults who had acted as language brokers in the course of their own school career (ex-CLBs ). The study addressed the following research questions in relation to both groups:
1. How often and for what purposes are CLBs used in schools?
2. To what degree are CLBs used in routine contacts with parents (their own & those of others), in more sensitive discussions about vulnerable pupils (e.g. about SEN) and in discussions when crucial matters are being resolved (e.g. planning for subject choices in Year 10)?
3. What are the perceived advantages and disadvantages of school language brokering arrangements?
4. How do teachers and ex-CLBs perceive CLBs in terms of their alignment with family or personal interests as against detached, independent values of translation and interpreting?
5. What views do ex-CLBs now have of their experience of the process, their own agency, competence and effectiveness and how the process was facilitated or obstructed by the actions and attitudes of their teachers?
6. What differences of view and understanding are there between teachers who are themselves bilingual or multilingual, teachers who are monolingual and ex-CLBs?
7. What recommendations would current teachers and ex-CLBs make on how to improve schools? policies and practices on CLB activity
Comparative analysis of carrying capacity indices for the central Aegean Islands
The tourist industry is one of the most important economic activities in Greece. The country receives over 14 million visitors per year. In an era where tourism is one of the fastest growing sectors of the developing countries the competition with existing tourism destinations, such as Greece, will intensify. Greece has enjoyed increasing numbers and revenues from tourism due to the unique environment both natural and man-made making it a high profile tourist destination. However, it is already clear, that the uncontrolled growth of the industry can bring serious environmental and social problems, leading to a decline in the quality of tourist product and services provided. Such negative effects can be controlled and reduced using environmental and tourism indices to estimate the impact of tourism and other businesses on the environment. The purpose of this paper is to apply the principles of coastal environmental management for the Islands in the central Aegean Sea islands via the carrying capacity assessment methodology in order to develop environmental performance indicators necessary for formulating a novel sustainable development policy proposal for Greek tourism.peer-reviewe
Mathematical analysis of a model for the growth of the bovine corpus luteum
The corpus luteum (CL) is an ovarian tissue that grows in the wound space created by follicular rupture. It produces the progesterone needed in the uterus to maintain pregnancy. Rapid growth of the CL and progesterone transport to the uterus require angiogenesis, the creation of new blood vessels from pre-existing ones, a process which is regulated by proteins that include fibroblast growth factor 2 (FGF2).\ud
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In this paper we develop a system of time-dependent ordinary differential equations to model CL growth. The dependent variables represent FGF2, endothelial cells (ECs), luteal cells, and stromal cells (like pericytes), by assuming that the CL volume is a continuum of the three cell types. We assume that if the CL volume exceeds that of the ovulated follicle, then growth is inhibited. This threshold volume partitions the system dynamics into two regimes, so that the model may be classified as a Filippov (piecewise smooth) system.\ud
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We show that normal CL growth requires an appropriate balance between the growth rates of luteal and stromal cells. We investigate how angiogenesis influences CL growth by considering how the system dynamics depend on the dimensionless EC proliferation rate, p5. We find that weak (low p5) or strong (high p5) angiogenesis leads to ‘pathological’ CL growth, since the loss of CL constituents compromises progesterone production or delivery. However, for intermediate values of p5, normal CL growth is predicted. The implications of these results for cow fertility are also discussed. For example, inadequate angiogenesis has been linked to infertility in dairy cows
Simulations and experimental demonstrations of encoding for X-ray coherent scattering
Diffraction data may be measured using approaches that lead to ambiguity in the interpretation of scattering distributions. Thus, the encoding and decoding of coherent scattering distributions have been considered with a view to enabling unequivocal data interpretation. Two encoding regimes are considered, where encoding occurs between the X-ray source and sample, and where the encoder is placed between the sample and detector. In the first case, the successful recovery of diffraction data formed from the interrogation of powder samples with annular incident beams is presented using a coded aperture approach. In the second regime, encoding of Debye cones is shown to enable recovery of the sample position relative to the detector. The errors associated with both regimes are considered and the advantages of combining the two discussed
Simulations and experimental demonstrations of encoding for X-ray coherent scattering
Diffraction data may be measured using approaches that lead to ambiguity in the interpretation of scattering distributions. Thus, the encoding and decoding of coherent scatter distributions have been considered with a view to enabling unequivocal data interpretation. Two encoding regimes are considered where encoding occurs between the X-ray source and sample, and where the encoder is placed between the sample and detector. In the first case, the successful recovery of diffraction data formed from the interrogation of powder samples with annular incident beams is presented using a coded aperture approach. In a second regime, encoding of Debye cones is shown to enable recovery of sample position relative to the detector. The errors associated with both regimes are considered and the advantages of combining both discussed
Depth resolved snapshot energy-dispersive X-ray diffraction using a conical shell beam
We demonstrate a novel imaging architecture to collect range encoded diffraction patterns from overlapping samples in a single conical shell projection. The patterns were measured in the dark area encompassed by the beam via a centrally positioned aperture optically coupled to a pixelated energy-resolving detector. We show that a single exposure measurement of 0.3 mAs enables d-spacing values to be calculated. The axial positions of the samples were not required and the resultant measurements were robust in the presence of crystallographic textures. Our results demonstrate rapid volumetric materials characterization and the potential for a direct imaging method, which is of great relevance to applications in medicine, non-destructive testing and security screening
Mathematical analysis of a model for the growth of the bovine corpus luteum.
The corpus luteum (CL) is an ovarian tissue that grows in the wound space created by follicular rupture. It produces the progesterone needed in the uterus to maintain pregnancy. Rapid growth of the CL and progesterone transport to the uterus require angiogenesis, the creation of new blood vessels from pre-existing ones, a process which is regulated by proteins that include fibroblast growth factor 2 (FGF2). In this paper we develop a system of time-dependent ordinary differential equations to model CL growth. The dependent variables represent FGF2, endothelial cells (ECs), luteal cells, and stromal cells (like pericytes), by assuming that the CL volume is a continuum of the three cell types. We assume that if the CL volume exceeds that of the ovulated follicle, then growth is inhibited. This threshold volume partitions the system dynamics into two regimes, so that the model may be classified as a Filippov (piecewise smooth) system. We show that normal CL growth requires an appropriate balance between the growth rates of luteal and stromal cells. We investigate how angiogenesis influences CL growth by considering how the system dynamics depend on the dimensionless EC proliferation rate, ρ₅. We find that weak (low ρ₅) or strong (high ρ₅) angiogenesis leads to 'pathological' CL growth, since the loss of CL constituents compromises progesterone production or delivery. However, for intermediate values of ρ₅, normal CL growth is predicted. The implications of these results for cow fertility are also discussed. For example, inadequate angiogenesis has been linked to infertility in dairy cows
Changes in the Isotopic Signature of Atmospheric Nitrous Oxide and Its Global Average Source During the Last Three Millennia
Nitrous oxide (N2O) is a strong greenhouse gas whose mole fraction in the atmosphere has increased over the industrial period. We present a new set of isotope measurements of N2O in air extracted from ice cores covering the last 3,000 years. For the preindustrial (PI) atmosphere, we find an average N2O mole fraction of (267 ± 1) nmol/mol and average tropospheric N2O isotopic values of δ15Nav PI = (9.5 ± 0.1)‰, δ18OPI = (47.1 ± 0.2)‰, δ15Nα PI = (17.8 ± 0.4)‰, and δ15Νβ PI = (1.2 ± 0.4)‰. From PI to modern times all isotope signatures decreased with a total change of δ15Nav = (−2.7 ± 0.2)‰, δ18O = (−2.5 ± 0.4)‰, δ15Nα = (−2.0 ± 0.7)‰, and δ15Νβ (−3.5 ± 0.7)‰. Interestingly, the temporal evolution is not the same for δ15Nav and δ18O. δ18O trends are relatively larger during the early part, and δ15Nav trends are larger during the late part of the industrial period, implying a decoupling of sources over the industrial period. Using a mass balance model, we determined the isotopic composition of the total average N2O source. Assuming that the total present source is the sum of a constant natural source and an increasing anthropogenic source, this anthropogenic source has an isotopic signature of δ15Nav source,anthrop = (−15.0 ± 2.6)‰, δ18Osource,anthrop = (30.0 ± 2.6)‰, δ15Nα source,anthrop = (−4.5 ± 1.7)‰, and δ15Nβ source,anthrop = (−24.0 ± 8.4)‰. The 15N site preference of the source has increased since PI times, which is indicative of a relative shift from denitrification to nitrification sources, consistent with agricultural emissions playing a major role in the N2O increase.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Constraining N2O emissions since 1940 using firn air isotope measurements in both hemispheres
N2O is currently the third most important anthropogenic greenhouse gas in terms of radiative forcing and its atmospheric mole fraction is rising steadily. To quantify the growth rate and its causes over the past decades, we performed a multi-site reconstruction of the atmospheric N2O mole fraction and isotopic composition using new and previously published firn air data collected from Greenland and Antarctica in combination with a firn diffusion and densification model. The multi-site reconstruction showed that while the global mean N2O mole fraction increased from (290±1)nmolmol-1 in 1940 to (322±1)nmolmol-1 in 2008, the isotopic composition of atmospheric N2O decreased by (-2.2±0.2)% for δ15Nav, (-1.0±0.3)% for δ18O, (-1.3±0.6)% for δ15Nα, and (-2.8±0.6)% for δ15Nβ over the same period. The detailed temporal evolution of the mole fraction and isotopic composition derived from the firn air model was then used in a two-box atmospheric model (comprising a stratospheric box and a tropospheric box) to infer changes in the isotopic source signature over time. The precise value of the source strength depends on the choice of the N2O lifetime, which we choose to fix at 123 years. The average isotopic composition over the investigated period is δ15Nav Combining double low line (-7.6±0.8)% (vs. air-N2), δ18O Combining double low line (32.2±0.2)% (vs. Vienna Standard Mean Ocean Water-VSMOW) for δ18O, δ15Nα Combining double low line (-3.0±1.9)% and δ15Nβ Combining double low line (-11.7±2.3)%. δ15Nav, and δ15Nβ show some temporal variability, while for the other signatures the error bars of the reconstruction are too large to retrieve reliable temporal changes. Possible processes that may explain trends in 15N are discussed. The 15N site preference (Combining double low line δ15Nα-δ15Nβ) provides evidence of a shift in emissions from denitrification to nitrification, although the uncertainty envelopes are large
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