The efficiency of education in generating literacy: a stochastic frontier approach

The growing importance attached to education as a key factor to improve economic performance coupled with the persistent scarcity of resources for education makes it important that skills and literacy are produced efficiently. This paper provides an international comparison of the efficiency of literacy production. We find substantial differences between countries in levels of literacy, differences in literacy between education levels and differences in the efficiency of literacy production. There are some notable differences between more Anglo-Saxon countries and the Continental European countries. The findings suggest that in almost all countries the scope for efficiency improvements in education is large. So even without major increases in (public) funding, improvements in educational outcomes are achievable. We can get better value for the money we spend on education.

Computerised Analysis, Interpretation, Storage and Retrieval of Electrocardiograms

A study was undertaken to determine the feasibility of introducing a computerised electrocardiographic analysis and interpretive system as a service to a teaching and referral hospital. Available computer equipment and programmes are considered. The accuracy and quality of the analysis and interpretation of the electrocardiographic contours are basically dependent on such factors as pattern recognition, the criteria adopted for determining abnormalities, the relative values placed on scalar and orthogonal leads and the role of review by the physician. It is concluded that such systems are at a stage where they can feasibly be introduced and should be of advantage in freeing the physician from ,routine measuring and screening of electrocardiograms, thus saving many hours of professional and academic time. Furthermore, such systems can contribute greatly as an educational tool and increase the general knowledge of electrocardiography. Systems for storage and retrieval are also being developed and becoming available. The whole field is a developing one and continuous updating of programmes by the addition of more data, particularly for children, and the introduction of electrocardiographic comparison programmes need to be expedited.S. Afr. Med. J., 48, 1141 (1974)

Neurocognitive functions in pathological gambling: A comparison with alcohol dependence, Tourette syndrome and normal controls.

Aims Neurocognitive functions in pathological gambling have relevance for the aetiology and treatment of this disorder, yet are poorly understood. This study therefore investigated neurocognitive impairments of executive functions in a group of carefully screened Diagnostic and Statistical Manual version IV (DSM-IV-TR) pathological gamblers. Performance was compared to a group of normal control participants. To study the specificity of these neurocognitive deficits, a substance dependence group (alcohol dependence) and an impulse control disorder group (Tourette syndrome) were included. Design Cross-sectional study. Setting Addiction and general mental health treatment centres. Participants Forty-nine pathological gamblers, 48 abstinent alcohol-dependent patients, 46 participants with Tourette syndrome and 49 normal control participants. Measurements A comprehensive neuropsychological battery measuring executive functions as well as basic cognitive functions. Findings Both the pathological gambling and the alcohol dependent groups were characterized by diminished performance on inhibition, time estimation, cognitive flexibility and planning tasks. The Tourette syndrome group showed deficits only on inhibition tasks. Basic cognitive functions were intact in all clinical groups. Comorbid attention deficit hyperactivity disorder, antisocial personality disorder and nicotine dependence influenced the impaired functions of the clinical groups only minimally. Conclusions Carefully screened groups of pathological gamblers and alcohol dependents were characterized by diminished executive functioning, suggesting a dysfunction of frontal lobe circuitry in these disorders. The resemblance between the pathological gambling group and the alcohol dependence group suggests a common neurocognitive aetiology for these disorders. Psychosocial treatment of these disorders could benefit from assessing and targeting deficits in executive functions, as they probably influence the course of these disorders negatively

A new find of Megalotragus priscus (Alcelaphini, Bovidae) from the central Karoo, South Africa

Main articleWe document the occurrence of the Florisian, or late Quaternary, form of the giant alcelaphine, Megalotragus priscus, from dongas on the Ongers River, near Britstown in the central Karoo. This is significant as it confirms the occurrence of the species in the Karoo and it suggests significantly wetter environments and productive grasslands in the central Karoo in pre-Holocene times. The present-day Karoo environment did not maintain populations of large ruminant grazers similar to M. priscus, and other specialized Florisian grazers, prior to the advent of agriculture and pasture management. Aridification in recent times is the likely cause of changes in grassland quality and the local dissappearance of these animals, if not their extinction.Non

Resonant Inelastic X-ray Scattering Studies of Elementary Excitations

In the past decade, Resonant Inelastic X-ray Scattering (RIXS) has made remarkable progress as a spectroscopic technique. This is a direct result of the availability of high-brilliance synchrotron X-ray radiation sources and of advanced photon detection instrumentation. The technique's unique capability to probe elementary excitations in complex materials by measuring their energy-, momentum-, and polarization-dependence has brought RIXS to the forefront of experimental photon science. We review both the experimental and theoretical RIXS investigations of the past decade, focusing on those determining the low-energy charge, spin, orbital and lattice excitations of solids. We present the fundamentals of RIXS as an experimental method and then review the theoretical state of affairs, its recent developments and discuss the different (approximate) methods to compute the dynamical RIXS response. The last decade's body of experimental RIXS data and its interpretation is surveyed, with an emphasis on RIXS studies of correlated electron systems, especially transition metal compounds. Finally, we discuss the promise that RIXS holds for the near future, particularly in view of the advent of x-ray laser photon sources.Comment: Review, 67 pages, 44 figure

Surface coating and particle size are main factors explaining the transcriptome-wide responses of the earthworm Lumbricus rubellus to silver nanoparticles

Due to the unique properties of differently sized and coated silver nanoparticles (AgNPs), they are used in important industrial and biomedical applications. However, their environmental fate in soil ecosystems and potential mechanisms of toxicity remain elusive, especially at the level of transcriptional regulation. We investigated the transcriptome-wide responses of the earthworm Lumbricus rubellus exposed to nine AgNPs differing in surface coating/charge (bovine serum albumin/negative AgNP_BSA, chitosan/positive AgNP_Chit, and polyvinylpyrrolidone/neutral AgNP_PVP) and sizes (20, 35 and 50 nm) at concentrations close to the EC50 value related to reproduction. AgNO3 was used in two concentrations to benchmark the AgNP effects against those of the Ag salt. A correlation was observed between the number of differentially expressed genes (DEGs) and Ag internal body concentration. Only metallothionein was regulated by all treatments. Medium sized AgNPs caused the most pronounced transcriptional responses, while AgNO3 affected the transcriptome less. Medium sized AgNP_BSA exposure caused the most extensive transcriptional responses with 684 DEGs. Gene ontology enrichment analysis of medium sized AgNP_BSA affected DEGs revealed that mitochondrial electron transport, autophagy and phagocytosis, mesoderm and heart development and microtubule organisation were affected. This was also confirmed by gene set enrichment for KEGG pathway analysis, indicating that phagocytosis, autophagy and signalling pathways related to mesoderm formation were significantly up regulated. All AgNP_BSA and AgNP_PVP exposures caused severe down regulation of ribosomal translation, suggesting that the high energy-demanding protein synthesis process is inhibited. Our data confirm the mechanisms previously identified among other animal models and human cell lines. To conclude, coating formulation and particle size severely impact transcriptional responses at a particular nanoparticle size, suggesting diverse mechanistic responses depending on the coating type

The human environmental balance

A future policy instrument for assessing the consequences of changes (already made) to the physical environment can be found in the instrument known as the human environmental balance. By taking all relevant aspects into account when using this instrument, present and future serious defects along with necessary areas of focus will become clear. In this way, the balance will fulfil an important evaluative and indicative function, serving as an integral conceptual framework to find out what investments to make and where they should be made. This report describes a survey, representing an initial step on the road to a balanced physical environment, charting further work along the way. It is also meant to stimulate a broad debate on how to audit this physical environment and what to study. The concept of the physical environment is defined as consisting of (stocks of) various objects in a certain (spatial) arrangement. These objects are evaluated from three perspectives: ecological, economic and social/psychological. The first two perspectives focus on long-term issues on sustainability. In the third perspective the central theme is the perception of the environment by humans themselves; here, we are concerned about short-term issues on the sub-national (local) level. The 1970-1995 draft balance also saw its first elaboration in this report.De leefomgevingsbalans is een door VROM voorgesteld toekomstig beleidsinstrument om gedane ingrepen in het fysieke milieu op hun integrale gevolgen voor de leefomgeving te beoordelen. De leefomgevingsbalans zou hiermee een belangrijke evaluerende en signalerende functie hebben: door beschouwing van alle relevante aspecten maakt de balans zichtbaar waar tekorten zijn of dreigen te ontstaan en waar extra inspanningen nodig zijn. Hiermee vormt de leefomgevingsbalans een integratief raamwerk dat richtinggevend kan zijn voor de aard en locatie van gewenste investeringen. Dit rapport is een verkenning van een mogelijk invulling van een dergelijke leefomgevingsbalans en dient uitsluitend als basis voor discussie. Het beschouwt de fysieke leefomgeving als een verzameling van (voorraden) van allerlei objecten in een bepaalde ruimtelijke configuratie. Deze objecten worden vanuit verschillende invalshoeken verschillend gewaardeerd. Hierbij is onderscheid gemaakt in een ecologisch, economisch en sociaal-psychologisch perspectief. De eerste twee perspectieven zijn vooral gericht op lange termijn-vraagstukken waarbij duurzaamheid voorop staat. Bij het laatste perspectief gaat om de individuele leefbaarheid van de burger, veelal handelend over korte termijn-vraagstukken op vooral lokaal niveau. Op deze wijze wordt het 'leefomgevingskapitaal' gepresenteerd als een drieluik van economische, ecologische en sociaal-psychologische waarden. In het rapport is ook een eerste uitwerking van dit concept voor de periode 1970-1995 gegeven

Time Evolution of tunneling and decoherence: soluble model

Decoherence effects associated to the damping of a tunneling two-level system are shown to dominate the tunneling probability at short times in strong coupling regimes in the context of a soluble model. A general decomposition of tunneling rates in dissipative and unitary parts is implemented. Master equation treatments fail to describe the model system correctly when more than a single relaxation time is involved