bluuebunny/crossref_metadata_2025 huggingface dataset:
ColRS two‐component system prevents lysis of subpopulation of glucose‐grown Pseudomonas putida
Authors: Putrinš Marta , Ilves Heili , Kivisaar Maia , Hõrak Rita
Published: July 2008

ColRS two‐component system is well conserved in pseudomonads, but its exact role has remained obscure. Here, we report that Pseudomonas putida deficient in ColR experiences serious carbon source‐specific stress that leads to the lysis of a subpopulation of bacteria growing on solid glucose medium. We observed that on glucose medium colR‐deficient bacteria aggregated, produced a Congo Red‐binding substance and had enhanced membrane permeability. Detection of a large amount of cytoplasmic β‐galactosidase and other proteins as well as chromosomal DNA in the growth medium of a colR mutant indicated that cell lysis took place if ColR was absent. Investigation of colony morphology revealed concavities in the centre of the colonies of colR mutant suggesting that cell lysis occurred mainly in the areas of the highest cell density. Analysis of bacteria at a single cell level by flow cytometry showed that population of glucose‐grown colR‐deficient cells was heterogeneous. In addition to the wild type‐like population, we detected a subpopulation of cells with damaged membrane permeable to propidium iodide. Interestingly, inactivation of oprB1 encoding a glucose porin eliminated the cell lysis as well as autoaggregation and membrane leakiness of a colR mutant indicating that glucose influx could be responsible for membrane stress in the absence of ColRS system.
Searching for new morphological characters in the systematics of scleractinian reef corals: comparison of septal teeth and granules between Atlantic and Pacific Mussidae
Authors: Budd Ann F. , Stolarski Jarosław
Published: July 2008

Recent molecular analyses have challenged the traditional classification of scleractinian corals at all taxonomic levels suggesting that new morphological characters are needed. Here we tackle this problem for the family Mussidae, which is polyphyletic. Most of its members belong to two molecular clades composed of: (1) Atlantic Mussidae and Faviidae (exceptMontastraea) and (2) Pacific Mussidae (Cynarina,Lobophyllia,Scolymia,Symphyllia) and Pectiniidae. Other Pacific mussids (e.g.Acanthastrea) belong to additional clades. To discover new characters that would better serve as phylogenetic markers, we compare the skeletal morphology of mussid genera in different molecular‐based clades. Three sets of characters are considered: (1) macromorphology (budding; colony form; size and shape of corallites; numbers of septal cycles), (2) micromorphology (shapes and distributions of septal teeth and granules), and (3) microstructure (arrangement of calcification centres and thickening deposits within costosepta). Although most traditional macromorphological characters exhibit homoplasy, several new micromorphological characters are effective at distinguishing clades, including the shapes and distribution of septal teeth and granules, the area between teeth, and the development of thickening deposits. Arrangements of calcification centres and fibres differ among clades, but the fine‐scale structure of thickening deposits does not.
Nitrofurantoin: the return of an old friend in the wake of growing resistance
Authors: Kashanian James , Hakimian Payam , Blute Michael , Wong Jean , Khanna Himmansh , Wise Gilbert , Shabsigh Ridwan
Published: July 2008

OBJECTIVE

To re‐evaluate the first‐ and second‐line therapies for treating uncomplicated urinary tract infection (UTI), as although fluoroquinolones are commonly used for this purpose, its level of use is thought to be inappropriately excessive and will eventually have a detrimental impact; thus we hypothesise that nitrofurantoin might be the best choice for this indication, due to its low frequency of use and its high susceptibility rate in common UTI pathogens.

MATERIALS AND METHODS

We retrospectively analysed antimicrobial susceptibility patterns of urinary isolates from 2003 to 2007, taken from a community‐based institutional hospital in Brooklyn, NY, USA.

RESULTS

In all, 10 417 cultures grewEscherichia colifrom 2003 to 2007. Overall, from 2003 to 2007, 95.6% ofE. coliurine isolates were susceptible to nitrofurantoin, with an average 2.3% resistance rate. By contrast,E. coliuropathogens had a mean 75.6% and 75.9% susceptibility and 24.2% and 24% resistance rate to both ciprofloxacin and levofloxacin, respectively. Co‐trimoxazole (trimethoprim/sulfamethoxazole; ‘TMP/SMX’) had a mean 29% resistance rate toE. coliover the same 5‐year period.

CONCLUSIONS

We consider that nitrofurantoin is a good fluoroquinolone‐sparing alternative to co‐trimoxazole; this study shows that nitrofurantoin is bactericidal to a mean of 95% ofE. coliUTIs. Nitrofurantoin also has a resistance rate of 2.3%, by contrast to the quinolones (ciprofloxacin and levofloxacin), with resistant rates of ≈24%, and Co‐trimoxazole, with a resistant rate of 29%. Nitrofurantoin is an acceptable treatment for uncomplicated UTIs and should now be considered the first‐line treatment. A reconsideration of UTI treatment guidelines might now be appropriate.
Developing an approach to defining the potential distributions of invasive plant species: a case study of Hakea species in South Africa
Authors: Le Maitre David C. , Thuiller Wilfried , Schonegevel Lucille
Published: July 2008

Aim  Models of the potential distributions of invading species have to deal with a number of issues. The key one is the high likelihood that the absence of an invading species in an area is a false absence because it may not have invaded that area yet, or that it may not have been detected. This paper develops an approach for screening pseudo‐absences in a way that is logical and defensible.

Innovation  The step‐wise approach involves: (1) screening environmental variables to identify those most likely to indicate conditions where the species cannot invade; (2) identifying and selecting the most likely limiting variables; (3) using these to define the limits of its invasion potential; and (4) selecting points outside these limits as true absence records for input into species distribution models.

This approach was adopted and used for the study of three prominent Hakea species in South Africa. Models with and without the false absence records were compared. Two rainfall variables and the mean minimum temperature of the coldest month were the strongest predictors of potential distributions. Models which excluded false absences predicted that more of the potential distribution would have a high invasion potential than those which included them.

Main conclusions  The approach of applying a priori knowledge can be useful in refining the potential distribution of a species by excluding pseudo‐absence records which are likely to be due to the species not having invaded an area yet or being undetected. The differences between the potential distributions predicted by the different models convey more information than making a single prediction, albeit a consensus model. The robustness of this approach depends strongly on an adequate knowledge of the ecology, invasion history and current distribution of that species.
Impact of investors’ status on their evaluation of positive and negative, and past and future information
Authors: Cianci Anna M. , Falsetta Diana
Published: July 2008

This paper examines the effect of investors’ status (current and prospective) on their evaluation of information varying in valence (negative and positive) and temporality (past and future). Master of Business Administration graduates, proxying for current or prospective investors, rated the relevance of negative, positive, past, and future Management Discussion and Analysis information. Investors’ relevance ratings of information resulted in the following ranking (from highest to lowest): negative‐future, negative‐past, positive‐future, and positive‐past information. Furthermore, prospective investors (relative to current) rated positive and future information as more relevant and negative information as less relevant. Implications for effective disclosure strategies and policies are discussed.
AN EMPIRICAL SURVEY OF RESIDENTIAL WATER DEMAND MODELLING
Authors: Worthington Andrew C. , Hoffman Mark
Published: July 2008

Abstract The increased reliance on demand‐side management policies as an urban water consumption management tool has stimulated considerable debate among economists, water utility managers, regulators, consumer interest groups and policymakers. In turn, this has fostered an increasing volume of literature aimed at providing best‐practice estimates of price and income elasticities, quantifying the impact of non‐price water restrictions and gauging the impact of non‐discretionary environmental factors affecting residential water demand. This paper provides a synoptic survey of empirical residential water demand analyses conducted in the last 25 years. Both model specification and estimation and the outcomes of the analyses are discussed.
PLACE, PRINT AND MIRACLE: FORLÍ'S MADONNA OF THE FIRE AS FUNCTIONAL SITE
Authors: PON LISA
Published: July 2008

The Madonna of the Fire of Forlì is an early woodcut that miraculously survived a fire in 1428, and still resides in the cathedral of Forlì, a city southeast of Bologna. This miracle removed the woodcut from the traffic in images crossing geographic and chronological boundaries in which other early modern prints participated. Since 1428 it has acted instead as a functional site, bound to a single place and able to galvanize disparate local elements into a communal sense of emplacement. This essay explores both that ability to generate a local identity, as well as the Madonna of the Fire's status as a miraculous object. For the transformation of the Madonna of the Fire from quotidian devotional print to miraculous cult icon also activated its ability to work as a functional site by charging overlapping material, geographic and discursive loci with communal significance.
From concepts of motivation to its application in instructional design: Reconsidering motivation from an instructional design perspective
Authors: Cheng Yi‐Chia , Yeh Hsin‐Te
Published: July 2008

This paper explores the concepts of motivation, including extrinsic motivation and intrinsic motivation. It describes how motivation becomes a major concern in the field of instructional design (ID). Furthermore, a motivation model—the ARCS model—is identified and discussed. Finally, it provides an example of how to apply the motivational design process in ID. The aim of this paper is to facilitate a deeper understanding of motivation and to inform professionals about its importance in learning
‘I've stuck to the path I'm afraid’: exploring student non‐use of blended learning
Authors: Orton‐Johnson Kate
Published: July 2008

This paper draws on qualitative data from a study of student use of blended learning as part of a conventionally taught undergraduate Sociology course. Findings from an early evaluation questionnaire highlighted an overwhelming pattern of non‐use of the materials and subsequent research with a group of 16 students evidenced limited and inconsistent engagement with the resources. In an analysis of the category ‘non‐use’, the students’ rejection of the materials is seen to be closely related to a trust in traditional texts as authentic academic knowledge and an instrumental and strategic approach to study. Blended learning resources are shown to challenge existing learning patterns and practices, reconfigure existing understandings and expectations of academic scholarship and reconstruct academic boundaries in new spaces.
Diversity in the School Problems of Economically Disadvantaged Adolescents: Dual Pathways of Reading and Externalizing Problems
Authors: Ackerman Brian , Smith Clare , Kobak Roger
Published: July 2008

This study of economically disadvantaged 13‐year‐olds examined the relations between serious reading difficulties and clinical levels of externalizing behaviors in school. The variable‐centered results showed that family variables, adolescent verbal ability, and negative emotion patterns differed in uniquely predicting reading achievement and externalizing behaviors. The person‐centered analyses established robust groups of adolescents showing problems in a single domain, both domains, or neither domain, and that family and adolescent variables distinguished the adolescent groups in predictable ways. Longitudinal results available for a subsample showed that high problem levels for the groups were stable across elementary school and associated with first‐grade characteristics. The results provide evidence for relatively independent pathways of reading and externalizing difficulties for young disadvantaged adolescents.
Who Dislikes Whom, and For Whom Does It Matter: Predicting Aggression in Middle Childhood
Authors: Erath Stephen A. , Pettit Gregory S. , Dodge Kenneth A. , Bates John E.
Published: July 2008

This study investigated the role of mutual dislike dyads (MDDs) in the development of aggressive behavior across the middle childhood years. Of particular interest was whether involvement in MDDs predicted later aggression, and whether the magnitude of the association between MDDs and later aggression varied based on characteristics of target children and ‘others’ involved in their MDDs. Data were collected on a community sample of 453 children participating in an ongoing longitudinal study. Classroom peer nomination and rating‐scale measures were collected in kindergarten through third grade; aggressive behavior problems were assessed via teacher ratings in the early elementary years (kindergarten and first grade) and late elementary years (fourth and fifth grade). MDD involvement in the middle elementary years (second and third grade) was associated with higher levels of aggression in the late elementary years among boys (but not girls), and these predictions held after controlling for group‐level peer disliking in the middle elementary years, aggression in the early elementary years, and demographic variables. The association between MDD involvement and subsequent aggression was also qualified by the aggressiveness of others in children's MDDs: Having more MDDs predicted later aggression only among boys whose MDDs involved mostly non‐aggressive others.
Family‐centred practice: collaboration, competency and evidence
Authors: ESPE‐SHERWINDT MARILYN
Published: July 2008

In the 1990s, the developing field of early intervention with young children with disabilities and their families adopted family‐centred practice as its philosophical foundation. Family‐centred practice includes three key elements: (1) an emphasis on strengths, not deficits; (2) promoting family choice and control over desired resources; and (3) the development of a collaborative relationship between parents and professionals. During the last two decades, the field of early childhood disability has successfully defined the working principles of family‐centred practice for practitioners. Although research has acknowledged that the paradigm shift to family‐centred practice is neither simple nor easy, a substantive body of evidence demonstrates that (a) family‐centred practice can be linked to a wide range of demonstrated benefits for both children and families, and (b) families are more satisfied and find family‐centred practice to be more helpful than other models of practice.
Generalization of Jeffreys Divergence-Based Priors for Bayesian Hypothesis Testing
Authors: Bayarri M. J. , García-Donato G.
Published: July 2008

We introduce objective proper prior distributions for hypothesis testing and model selection based on measures of divergence between the competing models; we call them divergence-based (DB) priors. DB priors have simple forms and desirable properties like information (finite sample) consistency and are often similar to other existing proposals like intrinsic priors. Moreover, in normal linear model scenarios, they reproduce the Jeffreys–Zellner–Siow priors exactly. Most importantly, in challenging scenarios such as irregular models and mixture models, DB priors are well defined and very reasonable, whereas alternative proposals are not. We derive approximations to the DB priors as well as Markov chain Monte Carlo and asymptotic expressions for the associated Bayes factors.
DASSO: Connections Between the Dantzig Selector and Lasso
Authors: James Gareth M. , Radchenko Peter , Lv Jinchi
Published: July 2008

We propose a new algorithm, DASSO, for fitting the entire coefficient path of the Dantzig selector with a similar computational cost to the least angle regression algorithm that is used to compute the lasso. DASSO efficiently constructs a piecewise linear path through a sequential simplex-like algorithm, which is remarkably similar to the least angle regression algorithm. Comparison of the two algorithms sheds new light on the question of how the lasso and Dantzig selector are related. In addition, we provide theoretical conditions on the design matrix X under which the lasso and Dantzig selector coefficient estimates will be identical for certain tuning parameters. As a consequence, in many instances, we can extend the powerful non-asymptotic bounds that have been developed for the Dantzig selector to the lasso. Finally, through empirical studies of simulated and real world data sets we show that in practice, when the bounds hold for the Dantzig selector, they almost always also hold for the lasso.
METAEPISTEMOLOGY AND DIVINE REVELATION
Authors: BUCKAREFF ANDREI A.
Published: July 2008

In Crossing the Threshold of Divine Revelation, William Abraham offers a rich, subtle defense of an epistemology of divine revelation. In this paper, I focus on a cluster of metaepistemological claims made by Abraham. Specifically, I argue that Abraham's remarks about epistemic fit and the epistemic standards we bring to bear in making evaluations of divine revelation claims commit him to a species of epistemic relativism. I suspect, however, that Abraham does not think of himself as an epistemic relativist. If this is the case, then I believe Abraham needs to rethink his metaepistemological commitments that imply epistemic relativism.
A SUDDEN SURPRISE OF THE SOUL: THE PASSION OF WONDER IN HOBBES AND DESCARTES
Authors: DECKARD MICHAEL FUNK
Published: July 2008

Philosophy begins in wonder, according to Plato and Aristotle. However, they did not expand a great deal on what precisely wonder is. Does this fact alone not raise curiosity in us as to why this passion is important? What is its role in our thinking except to end as soon as one begins conceptually delimiting its nature? The thinkers Thomas Hobbes and René Descartes both expanded upon earlier brief articulations of wonder in natural, supernatural and practical ways. By means of an historical and philosophical examination of these two early modern thinkers, this article hopes to begin to answer the question: ‘What is wonder?’
Correlation of Population Parameters Leading to Power Differences In Association Studies with Population Stratification
Authors: He Y. , Jiang R. , Fu W. , Bergen A. W. , Swan G. E. , Jin L.
Published: July 2008

The power of statistical tests to measure effect sizes in the presence of population stratification is an important issue for the design and analysis of population‐based association studies. Comparisons of statistical tests have shown that the power of different statistical approaches varies in different genetic scenarios. However, the impact of stratified population parameters on statistical power is not yet understood in a general statistical framework, particularly the impact of correlated population parameters. To investigate such impact in detail, we implemented a genetic model for population‐based association studies with stratified samples and evaluated the impact on power with different genetic scenarios. The investigation shows that correlation between disease prevalence and risk allele frequency among subpopulations impacts statistical power. In a model with five subpopulations and moderate population divergence (Fst= 0.01), the correlation accounts for more than 85% of power difference. Our results also show that the estimation of genetic effect for candidate loci is biased by population divergence. Beneficial alleles could be wrongly characterized as risk alleles when prevalence differences and divergences of risk loci are large among subpopulations.
Can the Allelic Test be Retired from Analysis of Case‐Control Association Studies?
Authors: Zheng Gang
Published: July 2008

It has been stated that, when Hardy‐Weinberg equilibrium (HWE) holds in the combined case‐control samples, the allelic test is asymptotically equivalent to the trend test (for the additive model) for testing genetic association, and hence the allelic test should not be used. A recent publication shows that the allelic test and the trend test are asymptotically equivalent when HWE holds in the population. It is known that, when HWE does not hold, the trend test can still be used while the allelic test is no longer valid. Therefore, the allelic test is either not valid or is asymptotically equivalent to the trend test. It appears that the allelic test is a nuisance test. Can it be retired from the analysis of case‐control association studies? It all depends on data and model assumptions. We give conditions under which the allelic test and the trend test are asymptotically equivalent under both null and alternative hypotheses.
Probability that a Two‐Stage Genome‐Wide Association Study will Detect a Disease‐Associated SNP and Implications for Multistage Designs
Authors: Gail M. H. , Pfeiffer R. M. , Wheeler W. , Pee D.
Published: July 2008

Large two‐stage genome‐wide association studies (GWASs) have been shown to reduce required genotyping with little loss of power, compared to a one‐stage design, provided a substantial fraction of cases and controls, πsample, is included in stage 1. However, a number of recent GWASs have used πsample < 0.2. Moreover, standard power calculations are not applicable because SNPs are selected in stage 1 by ranking their p‐values, rather than comparing each SNP's statistic to a fixed critical value. We define the detection probability (DP) of a two‐stage design as the probability that a given disease‐associated SNP will have a p‐value among the lowest ranks of p‐values at stage 1, and, among those SNPs selected at stage 1, at stage 2. For 8000 cases and 8000 controls available for study and for odds ratios per allele in the range 1.1‐1.3, we show that DP is substantially reduced for designs with πsample≤ 0.25, and that DP cannot be appreciably increased by analyzing the stage 1 and stage 2 data jointly. These results suggest that multistage designs with small first stages (e.g. πsample≤ 0.25) should be avoided, and that additional genotyping in earlier studies with small first stages will yield previously unselected disease‐associated SNPs.
Dystrophin Nonsense Mutations Can Generate Alternative Rescue Transcripts in Lymphocytes
Authors: Nishiyama A. , Takeshima Y. , Zhang Z. , Habara Y. , Tran T. H. T. , Yagi M. , Matsuo M.
Published: July 2008

Secondary alterations in splicing have been reported to produce semi‐functional mRNA from several nonsense mutations in the dystrophin gene. Disruptions of exonic splicing enhancers by single nucleotide changes are thought to underlie such alterations. The precise frequencies of such nonsense mutation‐dependent splicing alterations, however, remain unknown. Here we analyzed the splicing patterns of dystrophin mRNA in lymphocytes from 38 patients with dystrophinopathies due to nonsense mutations in the dystrophin gene. In seven of the cases (18%), we observed partial skipping of the nonsense‐encoding exon. Two of the seven cases, however, exhibited complex activation of a nonsense mutation‐created splice site, which resulted in the generation of novel transcripts. Examination of cis‐regulatory splicing elements through calculation of splicing probability scores and identification of potential splicing enhancer or silencer sequences failed to disclose a single cause for exon skipping. Remarkably, individual differences in splicing patterns were observed for cells from patients with identical nonsense mutations (C.5899C>T). Although five cases produced semi‐functional dystrophin mRNAs, only one of these exhibited a mild clinical course. These results provide important insights about targets for exon skipping induced by candidate antisense oligonucleotides and for ribosomal read‐through of nonsense mutations.
Differences in startle reflex and prepulse inhibition in European‐Americans and African‐Americans
Authors: Hasenkamp Wendy , Norrholm Seth D. , Green Amanda , Lewison Barbara , Boshoven William , Keyes Megan , Duncan Erica
Published: July 2008

The acoustic startle reflex and its modulation by a prepulse are psychophysiological phenomena that are commonly studied to evaluate various aspects of information processing. Recent reports in human populations suggest that subjects from disparate racial backgrounds may have significant differences in the startle response. To determine if this pattern could be observed in our subject population and whether it extended to prepulse inhibition (PPI), we evaluated baseline startle parameters and PPI in 53 African‐Americans (AA) and 38 European‐Americans (EA). In AA compared to EA, mean startle magnitude and probability of blink response were lower, with no difference in habituation. PPI was greater in AA than EA when groups were matched on baseline startle magnitude. These findings support the idea of racial differences in startle response. Implications for study design are highlighted, and possible environmental and genetic influences are considered.
Superior temporal gyrus spectral abnormalities in schizophrenia
Authors: Edgar J. Christopher , Hanlon Faith M. , Huang Ming‐Xiong , Weisend Michael P. , Thoma Robert J. , Carpenter Bruce , Hoechstetter Karsten , Cañive José M. , Miller Gregory A.
Published: July 2008

Considerable evidence indicates early auditory stimulus processing abnormalities in schizophrenia, but the mechanisms are unclear. The present study examined oscillatory phenomena during a paired‐click paradigm in the superior temporal gyrus (STG) as a possible core problem. The primary question addressed is whether first click and/or second click group differences in the time‐domain evoked response in patients with schizophrenia are due to (1) group differences in the magnitude of poststimulus oscillatory activity, (2) group differences in poststimulus phase‐locking, and/or (3) group differences in the magnitude of ongoing background oscillatory activity. Dense‐array magnetoencephalography from 45 controls and 45 patients with schizophrenia produced left‐ and right‐hemisphere STG 50‐ and 100‐ms time‐frequency evoked, phase‐locking, and total power measures. Whereas first click 100‐ms evoked theta and alpha abnormalities were observed bilaterally, evoked low beta‐band differences were specific to the left hemisphere. Compared to controls, patients with schizophrenia showed more low‐frequency phase variability, and the decreased 100‐ms S1 evoked response observed in patients was best predicted by the STG phase‐locking measure.
Underlying mechanisms of the P3a task‐difficulty effect
Authors: Kimura Motohiro , Katayama Jun'ichi , Murohashi Harumitsu
Published: July 2008

In three‐stimulus oddball studies, even typical deviant stimuli elicited a large P3a event‐related brain potential (ERP) when target/standard discrimination was difficult. To investigate the underlying mechanisms, the effects of task difficulty on early deviant‐related ERPs were assessed. Four visual stimuli defined by an orthogonal combination of task‐relevant size (nontarget 80%, target 20%) and task‐irrelevant luminance (standard 80%, deviant 20%) were presented randomly, where two task difficulties (easy, difficult) were defined by target/nontarget discriminability. An increase in task difficulty enhanced P3a as well as a posterior negativity (change‐related negativity) and an anterior positivity (frontal positivity) elicited by deviant nontarget stimuli. These results suggest that attentional modulation of refractoriness‐based rareness detection and an attention‐triggering process underlie the P3a task‐difficulty effect.
Unvoluntary attentional capture in change blindness
Authors: Schankin Andrea , Wascher Edmund
Published: July 2008

Change blindness occurs when the presentation of successively presented pictures goes along with a simultaneous presentation of distractors (e.g., mudsplashes). An ERP component (N2pc) was used to track shifts of attention to lateralized changes under different attentional conditions. Observing central changes and not knowing about lateral changes elicited no N2pc. If lateral changes were task relevant, however, an N2pc was observed for both detected and undetected changes. Repeating the first task, lateral changes also evoked an N2pc, although they were again not task relevant. These results indicate that the transient of the change, although never occluded by mudsplashes, did not attract attention (bottom up) automatically but additional knowledge about its occurrence is necessary (top down). An attentional shift, however, does not necessarily lead to an aware representation of the change.
Locus of response slowing resulting from alternation‐based processing interference
Authors: Dudschig Carolin , Jentzsch Ines
Published: July 2008

In serial reaction time (RT) tasks, performance is strongly influenced by previous events. RT in Trial N is much slower after response changes than response repetitions from Trial N−2 to Trial N−1 when response–stimulus interval is short (I. Jentzsch & H. Leuthold, 2005). The aim of the present study was to investigate the mechanisms leading to this slowing by contrasting the idea of a hard bottleneck, postponing all subsequent processing, with a selective prolonging of postperceptual stages. We analyzed the lateralized readiness potential (LRP) and peak latencies of P1, N1, and P300 components in a choice RT task mapping four stimuli to two responses. Alternation‐based interference affected the S‐LRP interval but neither the LRP‐R interval nor the latency of P1, N1, and P300. These findings suggest that, whereas alternation‐based conflict originates at response‐related stages, postconflict slowing selectively affects central, premotoric processing.
An animal geography of avian feeding habits in Peterborough, Ontario
Authors: Campbell Michael
Published: July 2008

Animal geography, emphasising jointly ‘actant’ behaviour of animals and people, encourages an innovative rethink of animal ecology, including animal strategies, hopes and fears in foraging, in a co‐dependent framework with human behaviour. This paper studies bird–human reactions and feeding interactions in Peterborough, Ontario. It uses ecological survey methods, and also relies on alternative sources, including unique bird behaviours and ‘strategies’, intra‐species differences and human emotions, preferences and feeding strategies. Feeders’ presence attracted birds to non‐habitat areas, altering the ecology of avian presence and foraging, and preferential feeding created serious, previously non‐existent, inter‐species conflicts and inventive, usually successful reactions from birds. There were inter‐species, and in some cases intra‐species, hierarchies of dominance, based on possible avian decisionmaking co‐dependent with the human behaviours in the continually recreated and inflected spaces. This possibly anthropomorphic perspective of bird behaviour moves beyond established theories of adaptation and the relation of human–bird behavioural interactions to bird ecology.
Dialysis Rounds A Dialysis Case Presentation and Discussion Edited by Roger A. Rodby: Management of Refractory Ascites Using Nocturnal Home Hemodialysis
Authors: Pauly Robert P. , Sood Manish M. , Chan Christopher T.
Published: July 2008

Ascites in patients with end‐stage renal disease (ESRD) poses a challenging management scenario for nephrologists. We present two patients with ascites refractory to treatment with standard outpatient hemodialysis which resolved upon the initiation of nocturnal home hemodialysis (NHD). NHD is a form of intensive renal replacement therapy whereby patients receive up to 8 hours of continuous hemodialysis and ultrafiltration, five to seven times per week. In both cases, the ascites resolved within weeks of changing hemodialysis modalities. NHD allowed a significant reduction in ultrafiltration rates, which likely underlies the procedural tolerability and contributed to the successful outcomes. This option could be considered in the management of the patient with ESRD and refractory ascites.
Editorial: Diet, Inflammation, and Chronic Kidney Disease: Getting to the Heart of the Matter
Authors: Neade Tina , Uribarri Jaime
Published: July 2008

Cardiovascular disease (CVD) remains a leading cause of death in patients with chronic kidney disease (CKD). CVD is now thought to result from the interplay of several factors including inflammation, oxidative stress and endothelial dysfunction. Advanced glycation end products (AGE) are known to be elevated in patients with CKD and these compounds possess these pro‐oxidant, pro‐inflammatory and anti‐endothelial properties. There has been a great deal of literature linking diet and inflammation, and recent work has shown the diet to be a significant contributor to the body’s AGE pool. We herein hypothesize that a diet high in AGE plays an important role in the initiation of chronic subclinical inflammation that seems to underlie the high prevalence of CVD in CKD patients. Herein we will briefly examine the evidence linking different components of diet with inflammation in CKD patients. We will then focus on the role of dietary AGEs in inflammation and potentially CVD in CKD, and in conclusion, we will propose dietary modifications as part of a multifactorial approach to ameliorate unhealthy lifestyles among CKD patients. The most important message is that simple changes in culinary technique rather than in the food nutrient composition may be the most important part of preventing CVD in this population.
EFFECTS OF NUTRIENT ENRICHMENT ON PRIMARY PRODUCTION AND BIOMASS OF SEDIMENT MICROALGAE IN A SUBTROPICAL SEAGRASS BED1
Authors: Bucolo Philip , Sullivan Michael J. , Zimba Paul V.
Published: July 2008

Eutrophication of coastal waters often leads to excessive growth of microalgal epiphytes attached to seagrass leaves; however, the effect of increased nutrient levels on sediment microalgae has not been studied within seagrass communities. A slow‐release NPK Osmocote fertilizer was added to sediments within and outside beds of the shoal grass Halodule wrightii, in Big Lagoon, Perdido Key, Florida. Gross primary production (GPP) and biomass (HPLC photopigments) of sediment microalgae within and adjacent to fertilized and control H. wrightii beds were measured following two 4‐week enrichment periods during June and July 2004. There was no effect of position on sediment microalgal GPP or biomass in control and enriched plots. However, nutrient enrichment significantly increased GPP in both June and July. These results suggest that sediment microalgae could fill some of the void in primary production where seagrass beds disappear due to excessive nutrient enrichment. Sedimentary chl a (proxy of total microalgal biomass) significantly increased only during the June enrichment period, whereas fucoxanthin (proxy of total diatom biomass) was not increased by nutrient enrichment even though its concentration doubled in the enriched plots in June.
ABSENCE OF A LARGE BROWN MACROALGA ON URBANIZED ROCKY REEFS AROUND SYDNEY, AUSTRALIA, AND EVIDENCE FOR HISTORICAL DECLINE1
Authors: Coleman Melinda A. , Kelaher Brendan P. , Steinberg Peter D. , Millar Alan J. K.
Published: July 2008

Loss of habitat‐forming algae is increasingly prevalent in temperate marine ecosystems. Here, we document absence of an important habitat‐forming macroalga, Phyllospora comosa (Labill.) C. Agardh, along an urbanized coast in New South Wales (NSW), Australia. Dense Phyllospora canopies were common on shallow sublittoral reefs north and south of Sydney. In contrast, we did not find a single individual along ∼70 km of rocky coastline in the Sydney metropolitan region, despite historical evidence to suggest that it was very common half a century ago. Recolonization of this important habitat‐forming alga has not occurred on Sydney reefs despite improved water quality, protection of its habitat, and frequent long‐distance dispersal of Phyllospora wrack. While there are obvious limitations, historical information can be useful for identifying potential shifts in community structure to increase our understanding of contemporary ecological patterns.
PREDATION BY THE TOXIC DINOFLAGELLATE DINOPHYSIS FORTII ON THE CILIATE MYRIONECTA RUBRA AND OBSERVATION OF SEQUESTRATION OF CILIATE CHLOROPLASTS1
Authors: Nagai Satoshi , Nitshitani Goh , Tomaru Yuji , Sakiyama Sanae , Kamiyama Takashi
Published: July 2008

This is the first report of the propagation of the toxic dinoflagellate Dinophysis fortii Pavill. under laboratory conditions when fed on the marine ciliate Myrionecta rubra grown with the cryptophyte Teleaulax amphioxeia (W. Conrad) D. R. A. Hill. In contrast, reduced growth of D. fortii (max. of 3–4 divisions) and formation of small cells were observed in the absence of the ciliate or when provided with T. amphioxeia only as prey, showing that D. fortii cannot utilize T. amphioxeia as prey. In the TEM observation of D. fortii cells, which had fully fed on the ciliate prey, well‐developed chloroplasts (5–12 μm in length) were seen and three thylakoids were usually arranged in most of the chloroplasts observed, but chloroplasts having two thylakoids were sometimes confirmed. In cells starved for 4 weeks, decrease of chloroplast numbers and disappearance of large chloroplasts were observed, and only a few small chloroplasts (0.5–2 μm in length) remained in the marginal regions. In the observation of the sequestration process of the chloroplasts ingested from M. rubra by D. fortii, within 15 min after D. fortii captured M. rubra, incorporation of almost all of the chloroplasts was observed, while most of the other cell contents still remained in the M. rubra cell. After that, dispersion of the ingested chloroplasts toward the marginal regions was confirmed, suggesting that chloroplasts of M. rubra are ingested and dispersed in D. fortii cells in advance of the ingestion of the other cell contents to prevent them from being digested in food vacuoles. The ingested chloroplasts can also function as kleptoplastids.
ACCLIMATION TO LOW TEMPERATURE OF TWO ARTHROSPIRA PLATENSIS (CYANOBACTERIA) STRAINS INVOLVES DOWN‐REGULATION OF PSII AND IMPROVED RESISTANCE TO PHOTOINHIBITION1
Authors: Vonshak Avigad , Novoplansky Nurit
Published: July 2008

This study aimed to compare the ability of two Arthrospira platensis (Nordst.) Gomont strains, M2 and Kenya, isolated from two different habitats, to acclimate to low temperature (15°C). Both strains had similar growth rates at 30°C, but once acclimated to low temperature, M2 showed a greater decline in growth (59% vs. 41% in the Kenya strain). We suggest that the Kenya strain acclimated better to low temperature by down‐regulating its photosynthetic activity through (i) decreasing antenna size and thus reducing energy flux into the photosystems; (ii) decreasing reaction center density (RC/CSX) and the performance index, thus decreasing the trapping probability and electron transport rate while maintaining electron transport probability for electron transport beyond QA− unchanged; (iii) increasing the energy dissipation flux. In contrast, the M2 strain showed no difference in antenna size and exhibited a much lower decrease in RC/CSX and a lower dissipation rate. Hence, the Kenya strain minimized potential damage on the acceptor side of PSII compared to the M2 cells. Furthermore, acclimation to low temperature was accompanied by an improved mechanism for handling excess energy resulting in an enhanced ability of the Kenya strain to rapidly repair damaged PSII RCs and withstand a high photon flux density (HPFD) stress; this finding might be defined as a cross‐adaptation phenomenon. This study may provide a tool to identify strains suitable for outdoor mass‐production in different regions characterized by different climate conditions.
CULTURE OF THE HETEROTROPHIC DINOFLAGELLATE PROTOPERIDINIUM CRASSIPES (DINOPHYCEAE) WITH NONCELLULAR FOOD ITEMS1
Authors: Yamaguchi Aika , Horiguchi Takeo
Published: July 2008

The genus Protoperidinium is an assemblage of heterotrophic dinoflagellates, several species of which have been successfully cultured in the past using various photosynthetic algae as a food source. We succeeded in culturing Protoperidinium crassipes (Kof.) Balech on three separate occasions for periods ranging from 2 to 21 months using rice flour as a food source. In these cultures, unusual small types of cells that were never observed to actively feed sometimes appeared. We confirmed that P. crassipes in culture exhibited bioluminescence.
Adolescent and Adult Heart Rate Responses to Self‐Administered Ethanol
Authors: Ristuccia Robert C. , Spear Linda P.
Published: July 2008

Background:  Despite the fact that adolescent rats have repeatedly been found to consume more ethanol than adult rats in a variety of ethanol access paradigms, the exact cause of the increase in ethanol consumption during adolescence is not known. One possibility is that age differences in sensitivity to ethanol’s rewarding effects may contribute to the elevated intake seen among adolescents. Human studies have shown that autonomic effects of ethanol, particularly ethanol‐induced tachycardia, are correlated with the positive hedonic properties of the drug and, hence, may serve as a biomarker for reward.

Methods:  In this experiment, a limited‐access self‐administration paradigm was used to examine the autonomic effects of ethanol in outbred male adolescent and in adult Sprague‐Dawley rats under circumstances likely to reveal the rewarding value of ethanol.

Results:  The results indicated that voluntary ethanol consumption was greater in adolescent than adult rats and that only adolescents consumed enough of the saccharin‐sweetened ethanol solution to show a tachycardic effect greater than that seen in response to saccharin alone.

Conclusions:  To the extent that these tachycardic properties of ethanol are associated with the rewarding/hedonic properties of ethanol as previously reported in humans, these findings support the suggestion that adolescent animals may have found the ethanol‐containing solution to be more rewarding than the saccharin solution. A similar effect was not seen in adults, findings consistent with the notion that adult rats may not consume enough ethanol under these circumstances to experience its positive rewarding properties.
Electrophysiological Effects of Dizocilpine (MK‐801) in Adult Rats Exposed to Ethanol During Adolescence
Authors: Criado José R. , Wills Derek N. , Walker Brendan M. , Ehlers Cindy L.
Published: July 2008

Background:  Despite evidence showing persistent changes in N‐methyl‐D‐aspartate (NMDA)‐receptor function following ethanol (EtOH) exposure, the contribution of NMDA systems to the long‐term neurophysiological consequences of adolescent EtOH exposure is unclear. The aims of this study were the following: (1) to determine whether adolescent EtOH exposure produces neurophysiological changes after a prolonged withdrawal period in adult rats and (2) to assess protracted alterations in neurophysiological responses to the NMDA antagonist MK‐801 in adult rats exposed to EtOH during adolescence.

Methods:  Adolescent male Wistar rats were exposed to EtOH vapor for 12 h/d for 5 weeks. The effects of MK‐801 (0.0 to 0.1 mg/kg, intraperitoneally) on the electroencephalogram (EEG) and auditory event‐related potentials (ERPs) were assessed after 8 weeks of abstinence from EtOH.

Results:  Experiments in aim 1 revealed that adolescent EtOH exposure reduced EEG variability in the frontal cortex in the 4 to 6 Hz band but had no effect on cortical and hippocampal EEG power and ERPs. Experiments in aim 2 showed that MK‐801 significantly reduced EEG power in the parietal cortex (4 to 6 Hz, 6 to 8 Hz, 8 to 16 Hz, 16 to 32 Hz) and hippocampus (16 to 32 Hz) and EEG variability in the parietal cortex (6 to 8 Hz, 16 to 32 Hz) following adolescent EtOH exposure. MK‐801 produced a significant decrease in hippocampal EEG variability (4 to 6 Hz, 8 to 16 Hz, 16 to 32 Hz) in control, but not in EtOH‐exposed rats. MK‐801 reduced frontal P1 ERP amplitude and latency in response to the rare tone in EtOH‐exposed rats compared to controls. In contrast, MK‐801 significantly reduced P3 ERP amplitude and latency in control, but not in EtOH‐exposed rats.

Conclusions:  The effects of MK‐801 on hippocampal EEG variability and P3 ERP amplitude and latency are significantly attenuated after a prolonged withdrawal period following adolescent EtOH exposure. However, the inhibitory effects of MK‐801 on cortical and hippocampal EEG power were enhanced in rats exposed to EtOH during adolescence. Taken together, these data suggest protracted changes in NMDA systems following adolescent EtOH exposure.
Increase in Screening for Colorectal Cancer in Older Americans: Results from a National Survey
Authors: Chen Xiao , White Mary C. , Peipins Lucy A. , Seeff Laura C.
Published: July 2008

OBJECTIVES: To compare the proportions of the U.S. population aged 65 and older who underwent tests for colorectal cancer (CRC) in 2000 and 2005 to examine the effect of the change in Medicare reimbursement for screening colonoscopy that occurred in 2001.

DESIGN: National population‐based survey.

SETTING: United States.

PARTICIPANTS: A total of 6,035 respondents to the 2000 National Health Interview Survey (NHIS) and 5,490 respondents to the 2005 NHIS aged 65 and older.

MEASUREMENTS: A questionnaire was used to assess self‐reports of testing (colonoscopy, sigmoidoscopy, or home fecal occult blood test (FOBT)) for CRC. Estimates for the U.S. population were extrapolated from the survey results. To account for the complex sampling design, SUDAAN was used to calculate population sizes and proportions.

RESULTS: In U.S. adults aged 65 and older, the proportion reporting up‐to‐date CRC testing increased from 39.5% in 2000 to 47.1% in 2005. By 2005, endoscopy had become more common than home FOBT for CRC screening in older adults. In 2000 and in 2005, a higher proportion of men than women were screened across all age groups and for all screening modalities. The proportion screened declined with older age.

CONCLUSION: Substantial increases in CRC testing, particularly colonoscopy, followed changes in Medicare reimbursement for screening colonoscopy in adults aged 65 and older. Although nearly half of older adults were up to date with CRC tests, differences remained in the use of screening according to age and sex within this age group.