Slowing the stork : better health for women through family planning

Each year 500,000 women die from causes related to pregnancy - 99 percent of them in developing countries. While many of those pregnancies are unwanted and could have been prevented by family planning, only a minority of developing country couples use effective contraceptive methods. For some women, pregnancy represents a major health risk. Others, of lower risk, do not want any more children. This paper discusses the factors which determine women's use of contraceptives, and how family planning programs reach the large numbers of women at risk from further pregnancies. The most successful family planning policies offer women a variety of contraceptive methods tailored to specific age groups and educational levels. Much program experience suggests that family planning is one of, if not the most cost-effective means of averting maternal deaths. The savings generated by family planning services could be invested in saving the lives and health of women who do want to have more children.Health Monitoring&Evaluation,Adolescent Health,Reproductive Health,Early Child and Children's Health,Gender and Health

Hypergraphic matroids

A method of defining a matroid on the edge-set of a k-uniform hypergraph (a k-hypergraph) is defined, which is a generalisation of that used for defining a matroid on the edge-set of a graph; the matroids so defined are called "hypergraphic matroids". Analogues are found in hypergraphs of the concepts of trees, forests, circuits, cutsets and components; we show that two generalisations are necessary of the concept of a vertex in a graph - a vertex, and a (k-l)-subset of vertices of a k-hypergraph; we call such a subset a node. The class of hypergraphic matroids is not closed under contraction, but may be enlarged to the class of generalised hypergraphic matroids, which is the closure of the class of hypergraphic matroids under the operation of taking minors. These matroids are defined in an analogous way to hypergraphic matroids, but a particular type of submodular function is necessary, instead of the cardinality function used for hyper graphs. We show that no finite set of forbidden minors exists to characterise either harpergraphic or generalised hypergraphic matroids. There is, however, a lattice characterisation of hypergraphic matroids. Transversal matroids are hypergraphic, and we give a simple method of obtaining a presentation. We also prove that hypergraphic matroids are representable over every characteristic, and that binary generalised hypergraphic matroids are graphic. The graph-theoretic notion of series-parallel extension is generalised, motivated by hypergraph considerations, to a new operation called generalised series-parallel extension. This operation has many properties similar to series-parallel extension. Generalised seriesparallel networks are defined, and characterised by a set of six forbidden minors. An extension of this result characterises ternary base-orderable matroids. We show that the matroid of a hypergraph can be used to derive weak and strong colourings of the nodes, and that, under obvious necessary conditions, all such colourings arise in this way. Connectedness and paths are investigated, but the results obtained for hypergraphs are less satisfactory than those for graphs, largely because the concepts of "node" and "vertex" do not coincide for general k-hypergraphs

Photosynthesis by the pericarp of developing cereal grain

Some photosynthetic properties of the chlorophyll containing layers of the immature cereal pericarp are described.The tissue was found to be capable of high rates of photosynthesis as determined by light dependent oxygen evolution. These rates were, however, reduced when isolated pericarps were used.The activity and kinetic properties of the enzyme phosphoenol pyruvate carboxylase (EC 4.1.1. 31) were investigated in some detail. In general enzyme activity followed chlorophyll content of the pericarp, although these results depended upon the exact conditions of plant growth. The dependence of enzyme activity on phosphoenol pyruvate and glucose 6 - phosphate concentration was investigated. The kinetic properties of the barley pericarp enzyme were found to be very similar to that from the maize leaf.The pericarp was found to contain high concentrations of phenols. These could be oxidised either in non-enzymic reactions by metal ions or enzymically by polyphenol oxidase. Thus extraction and reaction media were devised in which enzyme degradation by the products of phenol oxidation was minimised.The products of carbon dioxide fixation in isolated pericarps were in part identified, and resembled those reported for plants having the pathway. Further, the measured enzyme activities correlated with those found in plants with this pathway. The metabolic events leading to the synthesis of phosphoenol pyruvate remain unresolved

Evaluating the Predictive Validity of the Speed DIAL Version of the DIAL-3, Developmental Indicators for the Assessment of Learning.

The primary purpose of this research was to validate psychometric integrity of the Speed DIAL screening instrument by establishing its predictive validity. The validation process included determining what, if any, associations existed between the predictor variable, Speed DIAL and the outcome variable, the Virginia Standards of Learning third-grade math and total English tests. Gender and age were factors in the study. Finally, certain intervening variables, those occurring after the predictor variable, but before the outcome variable, were included in the study. These interventions were supplementary programs or placements provided students in the hopes of positively influencing students\u27 academic performance. The documented interventions were: retention status, special education status, number of years participating in Title I math, number of years participating in Title I reading, and number of years participating in the Phonological Awareness Literacy Screening (PALS) program. Based on the findings, Speed DIAL does possess predictive qualities. There was a moderate correlation between Speed DIAL scores and Virginia Standards of Learning third-grade math and total English test scores. Speed DIAL\u27s overall effectiveness rating exceeded 75%. Females scored higher than males on the Speed DIAL, and there was a negative association between Speed DIAL and the documented intervening variables. Using the Elaboration Paradigm, these intervening variables validated the positive association between Speed DIAL scores and scores on the Virginia Standards of Learning third-grade tests

A Cross-National Examination of Expected Correlation of Computer Ethical Perceptions and User Computer Attitudes

This study examined computer ethical perceptions and computer use attitudes among three differing groups consisting of nationalities from the United States, Singapore and Hong Kong. The purpose of the study was to determine if computer attitudes have a moderating effect on the perceptions of computer ethical use across multiple cultural backgrounds. Evidence supporting this claim would add additional insight into previously discovered differences. This study found limited support for the suggested hypotheses, but confirmed fundamental cultural differences. Future research should examine other variables to determine if significant effects can be determined from unexamined variable

A study of relativistic electron flux enhancements in the Earth's outer radiation belt

The relativistic electron distribution that occupies the outer radiation belt has been observed to vary significantly during intervals of disturbed solar wind conditions. Of particular interest are the order of magnitude increases in the relativistic electron flux that sometimes, but not always, follow the onset of a magnetic storm. These currently unpredictable relativistic electron flux enhancements are potentially hazardous during space missions causing radiation damage to spacecraft instrumentation and to humans. The work presented here establishes the conditions in the solar wind that lead to such flux enhancements. In addition, through the combined analysis of electron and wave data we provide essential constraints for the numerous proposed mechanisms for the acceleration of relativistic electrons in the outer radiation belt. The study uses data from the two STRV micro-satellites, which uncommonly are in the necessary orbit to provide coverage of almost the total electron population of the outer radiation belt essential for understanding the dynamics of the electron population. Data on the > 0.75 MeV energy electrons is used to investigate the relationship between the electron flux enhancements during magnetic storms and the coincident solar wind and geomagnetic conditions. Three distinct different types of electron responses arc identified, with outcomes that are shown to strongly depend on the solar wind speed and in particular the interplanetary magnetic field orientation during the magnetic storm recovery phase. A number of the electron acceleration mechanisms proposed to explain relativistic electron flux enhancements are driven by Pc5 pulsations in the magnetosphere. We thus investigate the relationship between these waves and electron response during magnetic storms. The findings point to a strong correlation between the Pc5 energy present during flux enhancement events and the size of the subsequent flux increase. However, the strength of the Pc5 power falls off quickly in the vicinity of the peak flux enhancement. In order to separate non-adiabatic processes, such as electron loss and most importantly heating, from adiabatic effects, we represent the electron data in a canonical coordinate system of the three adiabatic invariants. M, J and &phis; during two case studies. Using this method we identify an internal source of accelerated relativistic electrons and a further source of relativistic electrons at larger L supplied via substorm injections and inward radial diffusion. We also confirm the absence of either source of relativistic electrons when the IMF is northward during the recovery phase. Finally we use the results to help validate or discredit the various proposed electron acceleration mechanisms and end by identifying the mechanism that fits most convincingly with the analysis