The Special Surveillance Breast Program: a model of intervention for women at high risk for breast cancer

The Special Surveillance Breast Program (SSBP) is a long-term, comprehensive, multidisciplinary program for women determined to be at high risk for the development of breast cancer. Because the women who attend this program are otherwise healthy but concerned about their risk for breast cancer, current and relevant information is required to address their concerns regarding the possibility of developing breast cancer. The purpose of this article is to describe the risk factors that indicate eligibility for the program, the structure of the program, and the results of an assessment that identified the needs of this special population.     

Contaminants in organically and conventionally produced winter wheat (Triticum aestivum) in Belgium

A database has been compiled with the levels of important contaminants (mycotoxins, heavy metals and pesticides) measured from 2002 to 2005 in winter wheat (Triticum aestivum) grown in Belgium according to the organic and conventional farming systems. Assuming no further change in contaminant levels during cereal processing and during the preparation of foodstuffs, conservative intakes are estimated for the consumers of cereal-based products such as flour, bread, breakfast cereals, dough and pastry. The results show that for the consumer of organic foodstuffs, estimated daily intakes are 0.56 µg deoxynivalenol (DON), 0.03 µg zearalenone (ZEA), 0.19 µg Cd, 0.28 µg Pb and 0.0006 µg Hg kg^-1 body weight, taking into account the average contaminant levels in unprocessed grains and the average cereal products consumptions in Belgium. For the consumers of conventional foodstuffs, the corresponding estimated daily intakes are 0.99 µg DON, 0.06 µg ZEA, 0.17 µg Cd, 0.12 µg Pb and 0.0007 µg Hg kg^-1 body weight. In addition, it appears that for the consumers of conventional products, intakes of some post-harvest insecticides have to be taken into account (0.11 µg chlorpyriphos-methyl, 0.2 µg dichlorvos and 0.24 µg pirimiphos-methyl kg^-1 bw). When expressed as a percentage of the tolerable/acceptable daily intake (TDI/ADI), it seems that the corresponding estimated (conservative) intakes are the highest for DON (56% for organic and 99% for conventional cereal products), ZEA (16% for organic and 32% for conventional cereal products), and Cd (19% for organic and 17% for conventional cereal products), all other estimated intakes of contaminants (including pesticides) being lower than 10% of the TDI/ADI.     

Mapping the social and behavioral sciences world-wide: Use of maps in portfolio analysis of national research efforts

We have developed a method to identify and map the internationally most visible research topics occurring in the social and behavioral sciences, as well as the topics which changed most over a decade. Methods and data relevent to a portfolio analysis of national research efforts are described. Keywords used by authors in scientific or scholarly publications provide a window on scientific developments and changes in scientific research. Using an interdisciplinary database, the SSCI, developments in publications were traced world-wide and for the US, UK, France, Germany, and the Netherlands. We compared two periods: 1981–85 and 1986–90 We discuss the major substantive developments occurring during 1981–1990, as visible in maps depicting both topics and disciplines. It is shown that the maps, enriched with scientometric indicators of strengths and weaknesses of national research efforts, can be important tools for science policy. The findings indicate that the research front on many topics in both social and behavioral sciences is international in the late 1980s.     

Metabolic consequences of phosphotransferase (PTS) mutation in a phenylalanine-producing recombinant Escherichia coli

E. coli strain PPA305, which has a wild-type PTS system, and PPA316, which utilizes a proton-galactose symport system for glucose uptake, were used as host strains to harbor a phenylalanine overproduction plasmid pSY130-14 and to study the effects of using different glucose uptake systems on phenylalanine production. The non-PTS strain (PPA316/pSY130-14) produced much less phenylalanine, ranging from 0 to 67% of that produced by the PTS strain (PPA305/pSY130-14) depending on cultivation conditions used. The non-PTS strain PPA316/pSY130-14 had an intracellular PEP concentration only one-sixth that of the PTS strain, PPA305/pSY130-14. Additionally, PPA316/pSY130-14 had a substantially lower energy state in terms of the size of the pool of high-energy phosphate compounds and the magnitude of the pH difference across the cytoplasmic membrane. The non-PTS strain consumed oxygen at a higher rate, attained lower biomass concentration, and produced no acetate and phenylalanine during fermentation, suggesting more carbon was oxidized to CO2, most likely through the TCA cycle. Analysis of intracellular fluxes through the central carbon pathways was performed for each strain utilizing exponential phase data on extracellular components and assuming quasi-steady state for intermediate metabolites. The non-PTS strain had a higher flux through pyruvate kinase (PYK) and TCA cycle which, in agreement with the observed higher oxygen uptake rate, suggests that more carbon was oxidized to CO2 through the TCA cycle. Further analysis using rate expression data for PYK and NMR data for the intracellular metabolites identified the regulatory properties of PYK as the probable cause for lower intracellular PEP levels in PPA316/pSY130-14.     

Guest Editors' Introduction

Journal of Signal Processing Systems -     

Right Hemisphere Sensitivity to Word- and Sentence-Level Context: Evidence From Event-Related Brain Potentials.

Researchers using lateralized stimuli have suggested that the left hemisphere is sensitive to sentence-level context, whereas the right hemisphere (RH) primarily processes word-level meaning. The authors investigated this message-blind RH model by measuring associative priming with event-related brain potentials (ERPs). For word pairs in isolation, associated words elicited more positive ERPs than unassociated words with similar magnitudes and onset latencies in both visual fields. Embedded in sentences, these same pairs showed large sentential context effects in both fields. Small effects of association were observed, confined to incongruous sentences after right visual hemifield presentation but present for both congruous and incongruous sentences after left visual hemifield presentation. Results do not support the message-blind RH model but do suggest hemispheric asymmetries in the use of word and sentence context during real-time processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the assessment of economic risk: factorial design versus Monte Carlo methods

The feasibility of large investment projects (such as gas transmission and power system projects) has many aspects. Usually, this problem cannot be modeled as a single optimization problem; instead, the multiple aspects (demand, supply, prices, investment costs) are modeled separately. Each aspect may require a large, nonlinear submodel. The results of such a submodel can often be summarized by one or a few variables, which combine all the submodel's information; for example, total demand is the sum of the demand per customer type, each type being modeled separately. Traditionally, the feasibility of the investment project is then judged by combining the results of the various submodels for the ‘base case’ values of all model inputs.This base case information, however, is not sufficient for the decision makers; they also like to know the economic risk they are taking. To assess this risk on the project level (Hertz, D. B., Risk analysis in capital investment. Harvard Business Review, 1964, 95–106) developed a method known as risk analysis. This method is based on the estimated probability distribution of a project's net present value (NPV). This distribution is obtained by introducing distributions for the model inputs. The project's economic risk is then. expressed as the probability of a negative NPV exceeding a critical value (say) α. Nowadays this approach is becoming popular, because many software packages (such as @RISK and Crystal Ball) facilitate such a risk analysis. Although Hertz's risk analysis is appealing, it has a number of theoretical and practical flaws, which may lead to wrong conclusions. These flaws are discussed in this paper.From a modelling point of view, Hertz's risk analysis is similar to analysing the technological or operational risk of an investment. However, economic risk and technological risk are different concepts that require different analyses. In this paper these differences are discussed and it is shown that Hertz's risk analysis does not measure what is normally meant by a project's economic risk. Furthermore, the information requirements for the application of risk analysis to large investment projects are formidable; this makes the results of Hertz's investment analysis unreliable. Less information is required by sensitivity analysis based on the statistical design of experiments (such as 2^k−P designs); this analysis is more robust, and leads to results that better satisfy the information needs of decision makers.