bluuebunny/crossref_metadata_2025 huggingface dataset:
Thought and Context
Authors: Corazza Eros
Published: March 2005

Focuses on the way in which our cognitive activity is context dependent. In developing an idea put forward by Perry (1986), it is shown how we can succeed in thinking about something without having to represent this very thing insofar as the aboutness of one’s thought may not be represented. To sustain this view, the chapter focuses on the phenomenon of tacit reference and shows how context may bridge the gap between a thought and the event it represents.
The Overmuch and Unfamiliar
Authors: Lennan Richard
Published: March 2005

In the light of the book's analysis of both the challenges facing the embrace of ecclesial faith and the resources of that faith, this chapter endeavours to express the possibilities for the church in the present. Of particular interest is the capacity of the church to undertake ‘inculturation’ in contemporary culture without the loss of its specific identity. In order to establish that point, the chapter returns to ‘tradition’ with a view to establishing that tradition, grounded as it is in the Holy Spirit, is able to develop, to be about change as well as preservation; tradition, then, can be a stimulus to creativity. The specific examples of possibilities for change that the chapter examines are ministry in the church and the role of women in the church. Concludes with an attempt to nominate the factors – pre‐eminent among which is openness to the Spirit – that might enable the communion of the church not only to develop alternatives to ‘the peril’, but also make more inviting the risk of ecclesial faith.
Rhetoric and the Construction of the Centre
Authors: Hindmoor Andrew
Published: March 2005

This chapter explores the rhetoric of invention, focusing on the kinds of arguments politicians use to persuade audiences. It discusses the kinds of rhetorical arguments politicians use, and the limits of rhetoric. It is argued that rhetoric can be used to change beliefs. However, it persuades an audience based on the beliefs it already has.
Rhetoric, New Labour, and the Constructionof the Centre
Authors: Hindmoor Andrew
Published: March 2005

This chapter examines New Labour’s efforts to rhetorically construct the political centre based on its policies on devolution, minimum wage, trade union recognition, and tax increase in the 2002 budget. It is argued that policies are not left-wing because policies are not ‘really’ anything. New Labour used definitions, comparisons, ridicule, authority, and arguments about cause and effect, contradiction, and sacrifice to persuade voters that its policies were at the political centre.
Innovation and the Construction of the Centre
Authors: Hindmoor Andrew
Published: March 2005

This chapter examines the concept of innovation. The assumption of calculative decision-making makes prediction and the attainment of equilibrium possible, but leaves no analytical room for innovation. It is argued that innovation gives politicians a choice of electoral strategies, that innovation is uncertain, and that beliefs about innovation are themselves constructed and contested.
Framing and the Construction of the Centre
Authors: Hindmoor Andrew
Published: March 2005

This chapter argues that the political centre is also constructed through framing. It discusses the nature of frames and framing effects. It argues that framing can be used to refer to the way in which parties develop competing definitions and constructions of election campaigns.
Framing, New Labour, and the Constructionof the Centre
Authors: Hindmoor Andrew
Published: March 2005

This chapter examines how New Labour sought to reframe several issues and events. It argues that framing is not an optional strategy used by parties, but an essential part of political competition. Parties do not simply defend policies, but frame the issues those policies relate to.
Conclusion
Authors: Hindmoor Andrew
Published: March 2005

This chapter discusses the four differences in the ways to view the process of party competition. These differences involve the relationship between the policies and positions of a party, the political significance of political arguments or spin, creativity, and the amount of choice parties have. Based on these, it is argued that New Labour’s electoral future remains uncertain.
“Money Attitudes” and Retirement Plan Design: One Size Does Not Fit All
Authors: MacFarland Donna M. , Marconi Carolyn D. , Utkus Stephen P.
Published: March 2005

The chapter examines how workers’ attitudes about money and retirement planning influence their participation in defined contribution (DC) pension plans. Workers were grouped into five “money attitude” clusters. Individuals showed difference preferences for the types of planning activities needed to be successful in conventional DC plans.
Implications of Pension Plan Features, Information, and Social Interactions for Retirement Saving Decisions
Authors: Duflo Esther , Saez Emmanuel
Published: March 2005

This chapter examines the factors influencing enrolment in 401(k) retirement plans. In one study, a random sample of employees was asked to attend a benefits information fair organised by the employer. It was found that employees’ decisions to participate in the plan were influenced by their peers rather than the information provided by the fair.
The International Finance Facility Proposal
Authors: Mavrotas George
Published: March 2005

Proposals for new institutional arrangements for Official Development Assistance (ODA) that exploit techniques for securitisation in the capital market can function as an innovative source for generating the funds necessary for the achievement of Millennium Development Goals (MDGs). This chapter takes as an example of this type of proposal the International Finance Facility (IFF) proposal published in the United Kingdom in January 2003 jointly by HM Treasury and the UK Department for International Development (DFID). It discusses the IFF proposal in detail, describing its main technical details and financial structure, and elaborating on crucially important administration and implementation issues. The proposal is evaluated in terms of both its potential advantages and its shortcomings, as well as suggesting ways to strengthen the proposal further. The key challenges for IFF are summarised in the concluding section.
A Global Lottery and a Global Premium Bond
Authors: Addison Tony , Chowdhury Abdur R.
Published: March 2005

Proposals are evaluated, from both an economic and an ethical viewpoint, for development funding through a global lottery, along with a complement to this: a global premium bond (a loan instrument in which the interest takes the form of a lottery prize, the capital being repayable on request, so that it has the characteristics of a savings product, which makes it potentially attractive to ethical investors). The chapter starts by looking at how a global lottery might work, evaluating the issue by discussing lottery operators and their regulation, the market for lotteries, competition between the global lottery and national lotteries, the challenge posed by Internet gambling, revenue‐raising potential, cross‐county equity, distributional and welfare effects, ethical issues, and development education. The potential for a global premium bond is then analysed, summarising the UK premium bond scheme as a model for a global version, setting out the modalities of a global premium bond and highlighting the differences from a global lottery. It is concluded that global versions of both a lottery and a premium bond are viable and complementary in mobilizing more development finance.
Inhibition of N2 Fixation in Soybean Is Associated with Elevated Ureides and Amino Acids
Authors: King C. Andy , Purcell Larry C.
Published: March 2005

Decreased N2 fixation in soybean (Glycine max) L. Merr. during water deficits has been associated with increases in ureides and free amino acids in plant tissues, indicating a potential feedback inhibition by these compounds in response to drought. We evaluated concentrations of ureides and amino acids in leaf and nodule tissue and the concurrent change in N2 fixation in response to exogenous ureides and soil-water treatments for the cultivars Jackson and KS4895. Exogenous ureides applied to the soil and water-deficit treatments inhibited N2 fixation by 85% to 90%. Mn fertilization increased the apparent catabolism of ureides in leaves and hastened the recovery of N2 fixation following exogenous ureide application for both cultivars. Ureides and total free amino acids in leaves and nodules increased during water deficits and coincided with a decline in N2 fixation for both cultivars. N2 fixation recovered to 74% to 90% of control levels 2 d after rewatering drought-stressed plants, but leaf ureides and total nodule amino acids remained elevated in KS4895. Asparagine accounted for 82% of the increase in nodule amino acids relative to well-watered plants at 2 d after rewatering. These results indicate that leaf ureides and nodule asparagine do not feedback inhibit N2 fixation. Compounds whose increase and decrease in concentration mirrored the decline and recovery of N2 fixation included nodule ureides, nodule aspartate, and several amino acids in leaves, indicating that these are potential candidate molecules for feedback inhibition of N2 fixation.
Uncertainty Distribution Associated with Estimating a Proportion in Microbial Risk Assessment
Authors: Miconnet Nicolas , Cornu Marie , Beaufort Annie , Rosso Laurent , Denis Jean‐Baptiste
Published: March 2005

The uncertainty associated with estimates should be taken into account in quantitative risk assessment. Each input's uncertainty can be characterized through a probabilistic distribution for use under Monte Carlo simulations. In this study, the sampling uncertainty associated with estimating a low proportion on the basis of a small sample size was considered. A common application in microbial risk assessment is the estimation of a prevalence, proportion of contaminated food products, on the basis of few tested units. Three Bayesian approaches (based on beta(0, 0), beta , and beta(l, 1)) and one frequentist approach (based on the frequentist confidence distribution) were compared and evaluated on the basis of simulations. For small samples, we demonstrated some differences between the four tested methods. We concluded that the better method depends on the true proportion of contaminated products, which is by definition unknown in common practice. When no prior information is available, we recommend the beta prior or the confidence distribution. To illustrate the importance of these differences, the four methods were used in an applied example. We performed two‐dimensional Monte Carlo simulations to estimate the proportion of cold smoked salmon packs contaminated by Listeria monocytogenes, one dimension representing within‐factory uncertainty, modeled by each of the four studied methods, and the other dimension representing variability between companies.
Modeling Growth of Clostridium perfringens in Pea Soup During Cooling
Authors: De Jong Aarieke E. I. , Beumer Rijkel R. , Zwietering Marcel H.
Published: March 2005

Clostridium perfringens is a pathogen that mainly causes food poisoning outbreaks when large quantities of food are prepared. Therefore, a model was developed to predict the effect of different cooling procedures on the growth of this pathogen during cooling of food: Dutch pea soup. First, a growth rate model based on interpretable parameters was used to predict growth during linear cooling of pea soup. Second, a temperature model for cooling pea soup was constructed by fitting the model to experimental data published earlier. This cooling model was used to estimate the effect of various cooling environments on average cooling times, taking into account the effect of stirring and product volume. The growth model systematically overestimated growth of C. perfringens during cooling in air, but this effect was limited to less than 0.5 log N/ml and this was considered to be acceptable for practical purposes. It was demonstrated that the growth model for C. perfringens combined with the cooling model for pea soup could be used to sufficiently predict growth of C. perfringens in different volume sizes of pea soup during cooling in air as well as the effect of stirring, different cooling temperatures, and various cooling environments on the growth of C. perfringens in pea soup. Although fine‐tuning may be needed to eliminate inaccuracies, it was concluded that the combined model could be a useful tool for designing good manufacturing practices (GMP) procedures.
Integration of Stochastic Effects and Data Uncertainties into the Design of Process Equipment
Authors: Knetsch Thomas , Hauptmanns Ulrich
Published: March 2005

Stochastic effects and data uncertainties are present in any engineering calculation. Their impact may be particularly important if they concern the design of process equipment. A calculation model for the dynamic behavior of a heat exchanger and procedures to deal with the related uncertainties are presented. Their propagation through the calculation by means of a Monte Carlo approach is shown. The temperature at the heat exchanger outlet and the step response of a sudden variation in the heat exchanger inlet temperature are simulated and evaluated by way of example. It is demonstrated that the inclusion of stochastic effects and uncertainties provides a more reliable basis for design decisions and hence reduces the probability of errors.
The Beneficial Effect of Concurrent Task-Irrelevant Mental Activity on Temporal Attention
Authors: Olivers Christian N.L. , Nieuwenhuis Sander
Published: March 2005

It is believed that the human cognitive system is fundamentally limited in deploying attention over time. This limitation is reflected in the attentional blink, the impaired ability to identify the second of two visual targets presented in close succession. We report the paradoxical finding that the attentional blink is significantly ameliorated when observers are concurrently engaged in distracting mental activity, such as free-associating on a task-irrelevant theme or listening to music. This finding raises questions about the fundamental nature of the attentional blink, and suggests that the temporal dynamics of attention are determined by task circumstances that induce either a more or a less distributed state of mind.
Inflammation‐induced hyperexcitability of nociceptive gastrointestinal DRG neurones: the role of voltage‐gated ion channels
Authors: Beyak M. J. , Vanner S.
Published: March 2005

Abstract  Gastrointestinal (GI) inflammation modulates the intrinsic properties of nociceptive dorsal root ganglia neurones, which innervate the GI tract and these changes are important in the genesis of abdominal pain and visceral hyperalgesia. neurones exhibit hyperexcitability characterized by a decreased threshold for activation and increased firing rate, and changes in voltage‐gated Na+ and K+ channels play a major role in this plasticity. This review highlights emerging evidence that specific subsets of channels and signalling pathways are involved and their potential to provide novel selective therapeutic targets for the treatment of abdominal pain.
Interpreting collimated beam ultraviolet photolysis rate data in terms of electrical efficiency of treatment
Authors: Sharpless Charles M , Linden Karl G
Published: March 2005

A novel approach is presented for using fluence-based rate constants from collimated beam ultraviolet (UV) degradation kinetics to estimate electrical efficiencies for large-scale treatment of chemical contaminants. Atrazine (ATZ) and N-nitrosodimethylamine (NDMA) are given as examples. The relative electrical efficiencies of medium-pressure (MP) and low-pressure (LP) mercury lamps for treating these contaminants estimated from collimated beam data compare favorably with data collected using a bench-scale annular reactor and two different waters. For the water with higher UV transmittance, ATZ degradation was more efficient with the MP lamp by 8%, while for the water with lower transmittance the LP lamp was more efficient by 4%. For NDMA, the LP lamp was more efficient than the MP lamp in both waters tested: it was 29% more efficient in the water with higher transmittance and 58% more efficient in the water with lower transmittance. Key words: chemical treatment, water treatment, ultraviolet radiation, pesticides, photochemical reactions, potable water, electric power demand.
Comparative analysis of the Saccharomyces cerevisiae and Caenorhabditis elegans protein interaction networks
Authors: Agrafioti Ino , Swire Jonathan , Abbott James , Huntley Derek , Butcher Sarah , Stumpf Michael PH
Published: March 2005

Background

Protein interaction networks aim to summarize the complex interplay of proteins in an organism. Early studies suggested that the position of a protein in the network determines its evolutionary rate but there has been considerable disagreement as to what extent other factors, such as protein abundance, modify this reported dependence.

Results

We compare the genomes of Saccharomyces cerevisiae and Caenorhabditis elegans with those of closely related species to elucidate the recent evolutionary history of their respective protein interaction networks. Interaction and expression data are studied in the light of a detailed phylogenetic analysis. The underlying network structure is incorporated explicitly into the statistical analysis. The increased phylogenetic resolution, paired with high-quality interaction data, allows us to resolve the way in which protein interaction network structure and abundance of proteins affect the evolutionary rate. We find that expression levels are better predictors of the evolutionary rate than a protein's connectivity. Detailed analysis of the two organisms also shows that the evolutionary rates of interacting proteins are not sufficiently similar to be mutually predictive.

Conclusion

It appears that meaningful inferences about the evolution of protein interaction networks require comparative analysis of reasonably closely related species. The signature of protein evolution is shaped by a protein's abundance in the organism and its function and the biological process it is involved in. Its position in the interaction networks and its connectivity may modulate this but they appear to have only minor influence on a protein's evolutionary rate.
Antiplatelet agents for prevention of pre-eclampsia and its consequences: a systematic review and individual patient data meta-analysis
Authors:   The Perinatal Antiplatelet Review of International Studies (PARIS) Collaboration Steering Group on behalf of the PARIS Collaboration,   The PARIS Collaboration
Published: March 2005

Background

There is now good evidence that antiplatelet agents (principally low dose aspirin) prevent pre-eclampsia, a leading cause of morbidity and mortality for pregnant women and their babies. A Cochrane Review identified moderate, but clinically important, reductions in the relative risks of pre-eclampsia (19%), preterm birth (7%) and perinatal mortality (16%) in women allocated antiplatelets, rather than placebo or no antiplatelet.

Uncertainty remains, however, about whether some women (in terms of risk) benefit more than others, what dose of aspirin is best and when in pregnancy treatment should ideally start. Rather than undertake new trials, the best way to answer these questions is to utilise existing individual patient data from women enrolled in each trial.

Methods/Design

Systematic review with meta-analysis based on individual patient data. This involves the central collection, validation and re-analysis of thoroughly checked data from individual women in all the available randomised trials.

The objective is to confirm that antiplatelet agents, given during pregnancy, will reduce the incidence of pre-eclampsia. The review will then determine the size of this effect, and whether antiplatelets delay the onset of pre-eclampsia or its impact on important outcomes for women and their babies. It will also explore whether the effect of antiplatelets differs by womens' risk profile; when commenced during pregnancy; and/or by dose.

Discussion

The PARIS (Perinatal Antiplatelet Review of International Studies) Collaboration has been formed to undertake the review. This will be the first individual patient data review in the perinatal field. Final results should be available by 2006–7.
Effects of exposure to a combination of zinc- and lead-spiked sediments on mouthpart development and growth in Chironomus tentans
Authors: Martinez Edward A. , Moore Barry C , Schaumloffel John , Dasgupta Nairanjana
Published: March 2005

Exposures to either zinc or lead in contaminated sediments have been shown to induce characteristic deformities in larval chironomids. This study examined the effects of exposure to lead and zinc in combination on Chironomus tentans larvae. Proportions of mouthpart deformities in populations of larvae reared in sediments containing nominal combinations of lead and zinc were tested for additive, synergistic, and antagonistic interactions using logistic regression. Metal body burdens, body size measurements, and survival were used to evaluate toxicity and developmental impacts. Results demonstrate zinc and lead mixtures produce fewer deformities than the individual metal, so their interaction may be characterized as antagonistic. However, exposure to the metal mixtures also caused delayed development and failure to hatch. The apparent decline in deformities may be an artifact of higher mortalities or developmental effects. This research provides better understanding of some of the problems and considerations for use of chironomid population deformity proportions in bioassessments for sediment metal contamination.
Toxicological profiling of sediments using in vitro bioassays, with emphasis on endocrine disruption
Authors: Houtman Corine J. , Cenijn Peter H. , Hamers Timo , Lamoree Marja H. , Legler Juliette , Murk Albertinka J. , Brouwer Abraham
Published: March 2005

In vitro bioassays are valuable tools for screening environmental samples for the presence of bioactive (e.g., endocrine-disrupting) compounds. They can be used to direct chemical analysis of active compounds in toxicity identification and evaluation (TIE) approaches. In the present study, five in vitro bioassays were used to profile toxic potencies in sediments, with emphasis on endocrine disruption. Nonpolar total and acid-treated stable extracts of sediments from 15 locations in the Rhine Meuse estuary area in The Netherlands were assessed. Dioxin-like and estrogenic activities (using dioxin-responsive chemical-activated luciferase gene expression [DR-CALUX] and estrogen-responsive chemical-activated luciferase gene expression [ER-CALUX] assays) as well as genotoxicity (UMU test) and nonspecific toxic potency (Vibrio fischeri assay) were observed in sediment extracts. For the first time, to our knowledge, in vitro displacement of thyroid hormone thyroxine (T4) from the thyroid hormone transport protein thransthyretin by sediment extracts was observed, indicating the presence of compounds potentially able to disrupt T4 plasma transport processes. Antiestrogenic activity was also observed in sediment. The present study showed the occurrence of endocrine-disrupting potencies in sediments from the Dutch delta and the suitability of the ER- and DR-CALUX bioassays to direct endocrine-disruption TIE studies.
Increased kidney, liver, and testicular cell death after chronic exposure to 17α-ethinylestradiol in medaka (Oryzias latipes)
Authors: Weber Lynn P. , Balch Gordon C. , Metcalfe Chris D. , Janz David M.
Published: March 2005

Sublethal effects observed in fish exposed to environmental estrogens may be mediated via stimulation of cell death. To investigate whether cell death is induced in fish after chronic exposure to estrogenic chemicals, Japanese medaka (Oryzias latipes) were exposed from hatch until sexual maturity to 10 ng/L 17α-ethinylestradiol (EE2) or acetone solvent (control). Cell death was evaluated in blinded histological sections of whole medaka using terminal dideoxynucleotidyl-mediated dUTP nick end-labeling (TUNEL), which labels nuclei of cells containing apoptotic or necrotic (fragmented) DNA. The major impact of EE2 exposure in both male and female medaka was to significantly increase the number of TUNEL-positive hepatocytes and kidney tubule cells compared to control. Cell morphology was consistent with apoptosis in the liver and cloudy swelling or necrosis in the tubule cells. The number of TUNEL-positive interstitial (hematopoietic) and glomerular cells was significantly greater in the kidneys of EE2-exposed male, but not female, medaka. The EE2 exposure also significantly increased the number of TUNEL-positive testicular cells in medaka compared to corresponding controls, namely Leydig cells, Sertoli cells, spermatocytes, and spermatids. In medaka with gonadal intersex, areas of fibrosis and areas containing female gonadal cells were relatively unstained with TUNEL. No effect of EE2 exposure on the number of TUNEL-positive ovarian somatic cells or on the rate of female ovarian follicle atresia was found. These results suggest that chronic exposure to EE2 in medaka is hepatotoxic and nephrotoxic in both sexes, whereas gonadal toxicity is specific to males.
An assessment of the bioaccumulation of estrone in Daphnia magna
Authors: Gomes Rachel L. , Deacon Hannah E. , Lai Ka M. , Birkett Jason W. , Scrimshaw Mark D. , Lester John N.
Published: March 2005

The bioaccumulation of estrone by Daphnia magna was determined. Direct uptake via the aqueous medium occurred within the first 16 h. A bioconcentration factor of 228 was established over all temporal periods. Ingestion via Chlorella vulgaris gave a partitioning factor of 24, which may approximate to a biomagnification factor assuming steady state conditions. These preliminary results indicate that the partitioning to Daphnia magna via the food source, C. vulgaris is less significant than bioconcentration.
Effect of 3,4,3′,4′-tetrachlorobiphenyl on the reworking behavior of Lumbriculus variegatus exposed to contaminated sediment
Authors: Landrum Peter F. , Leppänen Matti , Robinson Sander D. , Gossiaux Duane C. , Burton G. Allen , Greenberg Marc , Kukkonen Jussi V. K. , Eadie Brian J. , Lansing Margaret B.
Published: March 2005

The reworking response (bioturbation) of the oligochaete Lumbriculus variegatus was measured by following the burial rate and spread of a 137Cs marker layer translating worm activity into a biological burial rate (Wb) and a biological diffusion rate constant (Db) for surficial sediment mixing. Reworking was measured at 10 and 22°C in two sediments: a reference site sediment dosed with 3,4,3′,4′-tetrachlorobiphenyl (TCBP) and a field-collected sediment from a polychlorinated biphenyl (PCB)-contaminated site in Dicks Creek (DCC, Middletown, OH, USA). The body residue associated with response to TCBP also was determined. Reduction in the temperature from 22 to 10°C reduced both Wb and Db by a factor of approximately two. The internal TCBP concentration to reduce the Wb by 50% was 96 nmol/g (95% CI 45–225 nmol/g) and 124 nmol/g (40–547 nmol/g) (28 and 36 μg/g) wet weight at 22 and 10°C, respectively, and was independent of temperature. The Wb for the DCC sediment was lower than observed for the highest TCBP treatment. The internal body residue for total PCB for worms exposed to DCC sediment was 20-fold lower than TCBP in worms exposed to the lowest TCBP treatment on a molar basis. Comparing body residues of total PCB to TCBP assumes that the PCB congeners act additively on a molar basis. The DCC site contained a higher proportion of coarse material and a lower organic carbon concentration. The difference in sediment characteristics was assumed to be responsible for differences in the Wb.
Interlaboratory comparison of a reduced volume marine sediment toxicity test method using the amphipod Ampelisca abdita
Authors: Ferretti James A. , Calesso Diane F. , Lazorchak James M. , Dolce Thomas J. , Arnold Jennifer , Goodfellow William L. , Smith Mark E. , Serbst Jonathan R.
Published: March 2005

The U.S. Environmental Protection Agency has standardized methods for performing acute marine amphipod sediment toxicity tests. A test design reducing sediment volume from 200 to 50 ml and overlying water from 600 to 150 ml was recently proposed. An interlaboratory comparison was conducted to evaluate the precision of this reduced sediment volume toxicity test method using the marine amphipod Ampelisca abdita. A negative control and three sediment samples of varying degrees of toxicity ranging from low to high were tested by six laboratories. Complete agreement was reached in rank of relative toxicity for all samples tested by five out of six laboratories. Test acceptability for control survival was achieved by all laboratories, and 69% agreement in classification of the sediments as toxic or nontoxic was documented. Coefficients of variation in all test samples were similar to those reported in other interlaboratory studies using marine amphipods. Results of this study indicate that the reduced sediment volume test using A. abdita is a reliable and precise measure of acute toxicity in marine sediment samples.
Mechanistic approaches for evaluating the toxicity of reactive organochlorines and epoxides in green algae
Authors: Niederer Christian , Behra Renata , Harder Angela , Schwarzenbach René P. , Escher Beate I.
Published: March 2005

Reactive electrophilic chemicals, such as reactive organochlorine compounds or epoxides, react specifically with a broad spectrum of nucleophilic biomolecules, including proteins and DNA. Conventional toxicity tests for algae, involving the observation of growth inhibition, i.e., the inhibition of cell multiplication, after several days, yield unreliable information for risk assessment because reactive compounds hydrolyze to different extents during the exposure period. The diversity of their modes of toxic action further complicates effect assessment and calls for methods yielding additional information on the mechanisms of toxicity. One of the primary targets of reactive chemicals in cells is the tripeptide glutathione (GSH), which is important for detoxification but can also be regarded as a toxicity sensor because changes in glutathione levels indicate stress. A vital system for algae is the photosynthetic system, which is indirectly affected by reactive chemicals. The test systems developed in this study for the assessment of reactive toxicity toward algae were therefore based not only on nonspecific toxicity indicators like growth inhibition but also on indicators for disturbance of photosynthesis (inhibition of photosystem II quantum yield) and glutathione metabolism. The application of the developed test systems on Scenedesmus vacuolatus after short-term exposure of 2 h showed that these tests can be used as fast screening tests for algal toxicity and in mode-of-action-based test batteries.
Harbor seals (Phoca vitulina) in British Columbia, Canada, and Washington State, USA, reveal a combination of local and global polychlorinated biphenyl, dioxin, and furan signals
Authors: Ross Peter S. , Jeffries Steven J. , Yunker Mark B. , Addison Richard F. , Ikonomou Michael G. , Calambokidis John C.
Published: March 2005

The harbor seal (Phoca vitulina) can serve as a useful indicator of food web contamination by persistent organic pollutants (POPs) because of its high trophic level, wide distribution in temperate coastal waters of the Northern Hemisphere, and relative ease of capture. In 1996 through 1997, we live-captured 60 harbor seal pups from three regions, spanning remote (Queen Charlotte Strait, BC, Canada), moderately industrialized (Strait of Georgia, BC, Canada), and heavily industrialized (Puget Sound, WA, USA) marine basins straddling the Canada-United States border. Biopsy samples of blubber were taken and analyzed for congener-specific polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by using high-resolution gas chromatography-high-resolution mass spectrometry. Harbor seals in Puget Sound were heavily contaminated with PCBs, whereas seals from the Strait of Georgia had relatively high concentrations of PCDDs and PCDFs. Pattern evaluation and principal components analysis suggested that proximity to sources influenced the mixture to which seals were exposed, with those inhabiting more remote areas being exposed to lighter PCB congeners (those with lower Henry's law constant and KOW) that disperse more readily through atmospheric and other processes. Total toxic equivalents to 2,3,7,8-tetrachlorodibenzo-p-dioxin for the PCBs, PCDDs, and PCDFs suggest that Puget Sound seals are at greatest risk for adverse health effects, and that PCBs represent the class of dioxinlike contaminants of greatest concern at all sites.
Web search strategies and human individual differences: Cognitive and demographic factors, Internet attitudes, and approaches
Authors: Ford Nigel , Miller David , Moss Nicola
Published: March 2005

The research reported here was an exploratory study that sought to discover the effects of human individual differences on Web search strategy. These differences consisted of (a) study approaches, (b) cognitive and demographic features, and (c) perceptions of and preferred approaches to Web‐based information seeking. Sixty‐eight master's students used AltaVista to search for information on three assigned search topics graded in terms of complexity. Five hundred seven search queries were factor analyzed to identify relationships between the individual difference variables and Boolean and best‐match search strategies. A number of consistent patterns of relationship were found. As task complexity increased, a number of strategic shifts were also observed on the part of searchers possessing particular combinations of characteristics. A second article (published in this issue of JASIST; Ford, Miller, & Moss, 2005) presents a combined analyses of the data including a series of regression analyses.
Contribution of morphometry in the differential diagnosis of fine‐needle thyroid aspirates
Authors: Karslıoğlu Yıldırım , Celasun Bülent , Günhan Ömer
Published: March 2005

Background

Cytologic discrimination of cellular nodules, follicular adenoma, and follicular carcinoma in the thyroid is problematic. Methods are needed to achieve a reliable diagnosis. Some sophisticated tools, such as microarrays, offer great potential but lack accompanying morphologic information.

Methods

One hundred twelve samples obtained from patients with lesions histopathologically diagnosed as nodular goiter, follicular adenoma, follicular carcinoma, and papillary carcinoma were used. Eight geometric features, such as nuclear area and circular form factor, were measured. The dataset was divided into six overlapping groups to represent the frequently encountered situations in routine practice. Multivariate analysis of variance, Tukey's honestly significant differences test, and discriminant analysis were performed. Statistical analysis was carried out with two conceptually different approaches. In the first, data from all measured nuclei were used. In the second, a subset of data representing the most extreme values of variables was extracted from the entire dataset to simulate the “selection procedure” performed during conventional morphologic examination.

Results

When the selected dataset instead of data from all measured nuclei was used, the correct classification rates in discriminant analysis improved considerably.

Conclusions

Morphologic examination is based primarily on selection. Using data obtained from all of the cells in morphometry may cause a dilution effect in diagnostically important features. Morphometric studies may also be planned with a proper selection “bias.” This may be particularly helpful when isolated abnormal cells carry most of the diagnostic information. © 2005 Wiley‐Liss, Inc.
Inhibitors of ubiquitin‐dependent proteolysis can delay programmed cell death of adult intersegmental muscles in the moth Manduca sexta
Authors: Bayline Ronald J. , Dean Derek M. , Booker Ronald
Published: March 2005

In the moth Manduca sexta, intersegmental muscles (ISMs) undergo rapid programmed cell death (PCD) within 48 hr of adult emergence. ISM PCD involves ubiquitin‐dependent proteasomal degradation accompanied by the down‐regulation of expression of actin genes and the up‐regulation of degradative gene expression such as ubiquitin. Hemin chloride and N‐acetyl‐leu‐leu‐norleucinal (ALLN), both inhibitors of proteasomal activity, administered before adult emergence delayed PCD for up to 5 days in ISMs maintained from the larval stage, such as the dorsal internal medial muscle in abdominal segment 4 (DIM‐A4). ISMs that developed during metamorphosis from respecified larval muscles such as the DIM‐A2 were less dramatically affected. The increase in polyubiquitinated proteins and the decrease in actin mRNA expression accompanying maintained ISM PCD were delayed after inhibitor application. No changes were detected in respecified ISMs. These results reveal a regulatory role for proteasomal activity in an early stage of maintained ISM cell death. Developmental Dynamics 233:445–455, 2005. © 2005 Wiley‐Liss, Inc.
Activation of catechol‐O‐methyltransferase in astrocytes stimulates homocysteine synthesis and export to neurons
Authors: Huang Guowei , Dragan Magdalena , Freeman David , Wilson John X.
Published: March 2005

Elevation of the total homocysteine (tHcy) concentration in plasma has been implicated in neurodegeneration in patients with stroke, dementia, Alzheimer disease, and Parkinson disease. Because the mechanisms controlling brain tHcy are unknown, the present study investigated its synthesis and transport in primary rat brain cell cultures. We found that the catechol‐O‐methyltransferase (COMT) substrate 3,4‐dihydroxybenzoic acid (DHB) increased export of tHcy in astrocytes, but not in neurons. The export mechanism was selective for tHcy over cyst(e)ine, total glutathione (tGSH) or cysteinylglycine (Cys‐Gly). tHcy export from astrocytes was also induced by the COMT substrates levodopa (L‐DOPA), dopamine and quercetin, and it was blocked by the COMT inhibitors tropolone and entacapone. This export was associated with increased synthesis of tHcy because both intracellular and extracellular tHcy concentrations rose during COMT activation. Incubation in cyst(e)ine‐deficient medium inhibited the tHcy export response to COMT activation. Exogenous tHcy (100 μM) was accumulated into neurons, but not into astrocytes. We conclude that activation of COMT causes sustained synthesis of Hcy in astrocytes and transport of this amino acid to neurons.© 2005 Wiley‐Liss, Inc.
Adhesion‐dependent redistribution of MAP kinase and MEK promotes muscarinic receptor‐mediated signaling to the nucleus
Authors: Slack Barbara E. , Siniaia Marina S.
Published: March 2005

The mitogen‐activated protein kinases (MAPKs) are activated by extracellular signals, and translocate to the nucleus where they modulate transcription. Integrin‐mediated cell adhesion to extracellular matrix (ECM) proteins is required for efficient transmission of MAPK‐based signals initiated by growth factors. However, the modulation of G protein‐coupled receptor (GPCR) signaling by adhesion is less well understood. In the present study, we assessed the impact of cell adhesion on MAPK activation by muscarinic M3 receptors. The muscarinic agonist carbachol more efficiently promoted stress fiber formation and tyrosine phosphorylation of focal adhesion‐associated proteins in M3 receptor‐expressing cells adherent to fibronectin or collagen type I, as compared to polylysine. Overall MAPK activation was robust in cells adherent to all three substrata. However, total levels of MAPK and mitogen‐activated protein kinase kinase (MEK) in the nucleus were significantly greater in cells adherent to ECM proteins for 2.5 h, and levels of activated MAPK and MEK in the nuclei of these cells were higher following carbachol stimulation, relative to levels in cells adherent to polylysine. MEK inhibitors did not prevent adhesion‐dependent translocation of MAPK and MEK to the nucleus, and increased nuclear phospho‐MEK levels in carbachol‐stimulated cells. The results suggest that adhesion of cells to ECM triggers the redistribution of MAPK and MEK to the nucleus, possibly as a result of the cytoskeletal rearrangements that accompany cell spreading. This may represent a mechanism for priming the nucleus with MEK and MAPK, leading to more rapid and pronounced increases in intranuclear phospho‐MAPK upon GPCR stimulation. © 2005 Wiley‐Liss, Inc.
A note on Ramsey numbers for books
Authors: Nikiforov Vladimir , Rousseau Cecil C.
Published: March 2005

The book with n pages Bn is the graph consisting of n triangles sharing an edge. The book Ramsey number r(Bm,Bn) is the smallest integer r such that either Bm ⊂ G or Bn ⊂ G for every graph G of order r. We prove that there exists a positive constant c such that r(Bm,Bn) = 2n + 3 for all n ≥ cm. Our proof is based mainly on counting; we also use a result of Andrásfai, Erdős, and Sós stating that triangle‐free graphs of order n and minimum degree greater than 2n/5 are bipartite. © 2005 Wiley Periodicals, Inc. J Graph Theory
Switching stimulation patterns improves performance of paralyzed human quadriceps muscle
Authors: Scott Wayne B. , Lee Samuel C. K. , Johnston Therese E. , Binder‐Macleod Stuart A.
Published: March 2005

The clinical efficacy of functional electrical stimulation (FES) is limited by the rapid onset of fatigue. Functional electrical stimulation applications typically stimulate skeletal muscles with constant‐frequency trains (CFTs). Our laboratory has identified trains that we call doublet‐frequency trains (DFTs) and that produce greater forces than CFTs, but more fatigue during repetitive activation than comparable CFTs. The purpose of this study was to see whether a series of CFTs followed by DFTs would reach a targeted isometric peak force more times than either train type alone during repetitive isometric activation of the paralyzed quadriceps muscles of subjects with spinal cord injuries (SCI). The combination of CFTs followed by DFTs reached the targeted isometric force 14% more often than the CFTs alone and 18% more often than the DFTs alone. These findings confirm that switching train types may be a useful strategy to offset the rapid fatigue of the functionally important quadriceps muscle that persons with SCI experience when using FES. Muscle Nerve, 2005
Flaviviruses in motor neuron disease
Authors: Pamphlett Roger , Kum‐Jew Stephen , King Nicholas J. C.
Published: March 2005

Sporadic motor neuron disease (MND) causes a progressive loss of motor neurons. West Nile virus can attack motor neurons, so we examined whether flavivirus infection could be detected in MND cases. Spinal cord sections from 22 MND cases were stained immunohistochemically with a flavivirus‐specific antibody. No staining for flavivirus was seen in any case. Sporadic MND does not appear to arise from a recent infection with a flavivirus. Muscle Nerve, 2005
Work and retirement after cancer diagnosis
Authors: Bednarek, Heather L. , Bradley Cathy J.
Published: March 2005

A pilot telephone survey was administered to 253 cancer survivors, ages 35–75, 5–7 years after their diagnosis of breast, colorectal, lung, or prostate cancer. These survivors reported their demographic characteristics and, if they had retired, reasons for retirement and their impression of the retirement experience. Retirees were older, had less education and lower incomes, and fewer had health insurance through their current/former employer relative to employed survivors. Those who had retired, regardless of whether they retired before or after a cancer diagnosis, were similar in age, race/ethnicity, health insurance status, household income, and impressions of retirement. The results suggest that cancer may not negatively affect survivors' decision to retire or the quality of the retirement experience. © 2005 Wiley‐Liss, Inc. Res Nurs Health 28:126–135, 2005
The effect of resolution‐dependent global shape modifications on rigid‐body protein–protein docking
Authors: Segal Dadi , Eisenstein Miriam
Published: March 2005

Docking unbound molecules presents a challenge in the case where no prior biological or bioinformatic knowledge exists. This is mainly due to differences between the structures of the molecules when in a complex and in the free state. Presumably, these differences interfere with the ability of protein–protein docking algorithms, which rely on a dominant shape descriptor, to identify the correct solution and rank it higher than false solutions. In this study we verify the notion that small discords in the molecular fit can be eliminated by using appropriately designed low‐resolution shape descriptors, thereby improving the docking results. We exploit the inherent gradual resolution dependency of Fourier transforms and formulate a resolution‐dependent shape descriptor by truncating selected Fourier transform terms. Thus, different levels of shape modification are attained, affecting the degree of detail in the depiction of the molecular surface. We applied the modified descriptor to a selection of 23 protein–protein systems, using the unbound structures where possible. The docking results obtained with the new geometric descriptor were considerably superior to former results, improving the ranks of nearly correct solutions for 17 systems. Unification of the results of scans in which different resolutions were employed further improved the ranks of nearly correct solutions to less than 100 for 12 of the 23 systems and less than 300 for 20 systems. The new geometric descriptor can be combined with other descriptors, which typify the electrostatic or hydrophobic character of the molecular surface, and with external experimental or bioinformatic data. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Sex and age differences in fragility in a heart failure population
Authors: Altimir Salvador , Lupón Josep , González Beatriz , Prats Montserrat , Parajín Teresa , Urrutia Agustín , Coll Ramon , Valle Vicente
Published: March 2005

Background

Heart failure (HF) patients have a high degree of fragility and dependence from physical, cognitive and psychological points of view, and are a mainly geriatric population.

Aim

To detect the existence of fragility in all patients treated in a Heart Failure Unit and to evaluate age and sex differences.

Methods

All patients underwent a basic geriatric evaluation to detect possible loss of autonomy for doing basic and instrumental activities, cognitive deterioration, emotional disturbance or social risk.

Results

Three hundred sixty patients (mean age 65.2 years, 41.7% ≥70 years, 27.5% women) were evaluated. Fragility was detected in 41.7% of patients, being more prevalent in patients ≥70 years (p<0.001) and in women (p<0.001). A Barthel Index <90 was found in 22.5% of patients and an anomalous OARS Scale was found in 18.3%. Pfeiffer test's score was abnormal in 7.8% of patients. A positive depression response in abbreviate GDS was observed in 29.7%. All items analysed were more prevalent in patients ≥70 years and in women, with the unexpected exception of depression symptoms that were as prevalent in younger as in older patients.

Conclusion

Fragility is common in patients with heart failure, even in younger patients, and can be detected easily using standardised geriatric scales. Prevalence of fragility was significantly higher in older patients and in women, although the presence of depression symptoms was as prevalent in younger as in older patients.
Initiation of rain by turbulence‐induced condensational growth of cloud droplets
Authors: Tisler P. , Zapadinsky E. , Kulmala M.
Published: March 2005

Rain droplet formation due to condensational growth and small‐scale turbulent fluctuations is investigated. We report here the results of Monte Carlo type simulations of the droplet activation on cloud condensation nuclei and subsequent condensational growth in a turbulent cloud medium. According to modeling results relatively small fluctuations in temperature and water vapor concentration play essential role in droplet size distribution broadening and producing big cloud droplets, responsible for onset of fast coalescence growth and initiation of precipitation.