10,932 research outputs found

    The effect of school quality on educational attainment and wages

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    The paper examines the effects of school pupil-teacher ratios and type of school on educational attainment and wages using the British National Child Development survey (NCDS). The NCDS is a panel survey which has followed a cohort of individuals born in March 1958, and has a rich set of background variables recorded throughout the individual's life. The results suggest that, once we control for ability and family background, the pupil-teacher ratio has no impact on educational qualifications or on male wages. It has an impact on women’s wages at the age of 33, particularly those of low ability. We also find evidence that those who attend selective schools have better educational outcomes and, in the case of men, higher wages at the age of 33. The impact is higher for the type of individuals who are less likely not to attend selective schools, but for whom a comparison group does exist among those attending

    3D Effects Of The Entropic Force

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    This work analyzes the classical statistical mechanics associated to phase-space curves in three dimensions. Special attention is paid to the entropic force. Strange effects like confinement, hard core, and asymptotic freedom are uncovered. Negative specific heats, that were previously seen to emerge in a one-dimensional setting, disappear in 3D, and with them, gravitational effects of the entropic force.Comment: arXiv admin note: substantial text overlap with arXiv:1306.203

    Physical peculiarities of divergences emerging in q-deformed statistics

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    It was found in [Europhysics Letters {\bf 104}, (2013), 60003] that classical Tsallis theory exhibits poles in the partition function Z{\cal Z} and the mean energy . These occur at a countably set of the q-line. We give here, via a simple procedure, a mathematical account of them. Further, by focusing attention upon the pole-physics, we encounter interesting effects. In particular, for the specific heat, we uncover hidden gravitational effects.Comment: 21 pages, 3 figures. Title has changed. Text has change

    VGF changes during the estrous cycle: a novel endocrine role for TLQP peptides?

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    Although the VGF derived peptide TLQP-21 stimulates gonadotropin-releasing hormone (GnRH) and gonadotropin secretion, available data on VGF peptides and reproduction are limited. We used antibodies specific for the two ends of the VGF precursor, and for two VGF derived peptides namely TLQP and PGH, to be used in immunohistochemistry and enzyme-linked immunosorbent assay complemented with gel chromatography. In cycling female rats, VGF C-/N-terminus and PGH peptide antibodies selectively labelled neurones containing either GnRH, or kisspeptin (VGF N-terminus only), pituitary gonadotrophs and lactotrophs, or oocytes (PGH peptides only). Conversely, TLQP peptides were restricted to somatostatin neurones, gonadotrophs, and ovarian granulosa, interstitial and theca cells. TLQP levels were highest, especially in plasma and ovary, with several molecular forms shown in chromatography including one compatible with TLQP-21. Among the cycle phases, TLQP levels were higher during metestrus-diestrus in median eminence and pituitary, while increased in the ovary and decreased in plasma during proestrus. VGF N- and C-terminus peptides also showed modulations over the estrous cycle, in median eminence, pituitary and plasma, while PGH peptides did not. In ovariectomised rats, plasmatic TLQP peptide levels showed distinct reduction suggestive of a major origin from the ovary, while the estrogen-progesterone treatment modulated VGF C-terminus and TLQP peptides in the hypothalamus-pituitary complex. In in vitro hypothalamus, TLQP-21 stimulated release of growth hormone releasing hormone but not of somatostatin. In conclusion, various VGF peptides may regulate the hypothalamus-pituitary complex via specific neuroendocrine mechanisms while TLQP peptides may act at further, multiple levels via endocrine mechanisms involving the ovary

    Origins of plateau formation in ion energy spectra under target normal sheath acceleration

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    Target normal sheath acceleration (TNSA) is a method employed in laser--matter interaction experiments to accelerate light ions (usually protons). Laser setups with durations of a few 10 fs and relatively low intensity contrasts observe plateau regions in their ion energy spectra when shooting on thin foil targets with thicknesses of order 10 μ\mathrm{\mu}m. In this paper we identify a mechanism which explains this phenomenon using one dimensional particle-in-cell simulations. Fast electrons generated from the laser interaction recirculate back and forth through the target, giving rise to time-oscillating charge and current densities at the target backside. Periodic decreases in the electron density lead to transient disruptions of the TNSA sheath field: peaks in the ion spectra form as a result, which are then spread in energy from a modified potential driven by further electron recirculation. The ratio between the laser pulse duration and the recirculation period (dependent on the target thickness, including the portion of the pre-plasma which is denser than the critical density) determines if a plateau forms in the energy spectra.Comment: 11 pages, 12 figure

    A first order Tsallis theory

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    We investigate first-order approximations to both i) Tsallis' entropy SqS_q and ii) the SqS_q-MaxEnt solution (called q-exponential functions eqe_q). It is shown that the functions arising from the procedure ii) are the MaxEnt solutions to the entropy emerging from i). The present treatment is free of the poles that, for classic quadratic Hamiltonians, appear in Tsallis' approach, as demonstrated in [Europhysics Letters {\bf 104}, (2013), 60003]. Additionally, we show that our treatment is compatible with extant date on the ozone layer.Comment: 4 figures adde

    USING SCAFFOLDING TECHNIQUE TO IMPROVE THE SPEAKING SKILL OF THE SECOND SEMESTER STUDENTS OF ENGLISH DEPARTMENT

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    Ada anggapan bahwa pengetahuan kebahasaan seseorang diukur dari kemampuan berbicara. Berbicara adalah sarana yang mendasar dalam komunikasi manusia, demikian juga mahasiswa Bahasa Inggris, mereka juga dituntut untuk bisa berbicara dalam Bahasa Inggris dengan baik. Parameter seorang pembelajar  Bahasa Inggris adalah kemampuannya berbicara secara lancar. Namun kenyataan menunjukkan bahwa banyak pembelajar yang tidak bisa berbicara dengan tepat dan lancar walaupun sudah belajar selama 6 tahun.Capaian ketrampilan berbicara pembelajar dipengaruhi beberapa faktor, yaitu faktor eksternal dan internal. Motivasi adalah satu dari faktor internal yang berperan penting dalam kesuksesan belajar. Faktor yang berikutnya adalah teknik yang digunakan oleh guru.Scaffolding adalah suatu jembatan yang menghubungkan pengetahuan yang dimiliki dengan hal yang belum diketahui. Jika dilaksanakan dengan baik, scaffolding akan menjadi daya yang memicu pembelajar untuk menguasai sesuatu. Dalam proses ini pembimbing memfasilitasi pembelajar untuk menguasai konsep yang tidak dapat dikuasai pembelajar. Pembimbing tidak hanya memberikan bantuan tetapi juga harus sebisa mungkin memberikan kebebasan bagi pembelajar untuk menyelesaikan tugas-tugas secara mandiri. Ketika pembelajar sudah  bisa bertanggung jawab atau menyelesaikan suatu tugas secara mandiri, maka pembimbing secara bertahap menjauh dan memberikan kebebasan untuk belajar secara mandiri. Keyword : Scaffolding  Technique, Speaking Skil

    Combined Effects of the North Atlantic Oscillation and the Arctic Oscillation on Sea Surface Temperature in the Alborán Sea

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    We explored the possible effects of the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) on interannual sea surface temperature (SST) variations in the Albora´n Sea, both separately and combined. The probability of observing mean annual SST values higher than average was related to NAO and AO values of the previous year. The effect of NAO on SST was negative, while that of AO was positive. The pure effects of NAO and AO on SST are obscuring each other, due to the positive correlation between them. When decomposing SST, NAO and AO in seasonal values, we found that variation in mean annual SST and mean winter SST was significantly related to the mean autumn NAO of the previous year, while mean summer SST was related to mean autumn AO of the previous year. The one year delay in the effect of the NAO and AO on the SST could be partially related to the amount of accumulated snow, as we found a significant correlation between the total snow in the North Albora´n watershed for a year with the annual average SST of the subsequent year. A positive AO implies a colder atmosphere in the Polar Regions, which could favour occasional cold waves over the Iberian Peninsula which, when coupled with precipitations favoured by a negative NAO, may result in snow precipitation. This snow may be accumulated in the high peaks and melt down in spring-summer of the following year, which consequently increases the runoff of freshwater to the sea, which in turn causes a diminution of sea surface salinity and density, and blocks the local upwelling of colder water, resulting in a higher SST.CGL2009-11316 (Ministerio de Ciencia e Innovación, Spain, and FEDER
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