bluuebunny/crossref_metadata_2025 huggingface dataset:
Muscle representation in the macaque motor cortex: An anatomical perspective
Authors: Rathelot Jean-Alban , Strick Peter L.
Published: May 2006

How are the neurons that directly influence the motoneurons of a muscle distributed in the primary motor cortex (M1)? To answer this classical question we used retrograde transneuronal transport of rabies virus from single muscles of macaques. This enabled us to define cortico-motoneuronal (CM) cells that make monosynaptic connections with the motoneurons of the injected muscle. We examined the distribution of CM cells that project to motoneurons of three thumb and finger muscles. We found that the CM cells for these digit muscles are restricted to the caudal portion of M1, which is buried in the central sulcus. Within this region of M1, CM cells for one muscle display a remarkably widespread distribution and fill the entire mediolateral extent of the arm area. In fact, CM cells for digit muscles are found in regions of M1 that are known to contain the shoulder representation. The cortical territories occupied by CM cells for different muscles overlap extensively. Thus, we found no evidence for a focal representation of single muscles in M1. Instead, the overlap and intermingling among the different populations of CM cells may be the neural substrate to create a wide variety of muscle synergies. We found two additional surprising results. First, 15–16% of the CM cells originate from area 3a, a region of primary somatosensory cortex. Second, the size range of CM cells includes both “fast” and “slow” pyramidal tract neurons. These observations are likely to lead to dramatic changes in views about the function of the CM system.
Connecting stuttering management and measurement: V. Deduction and induction in the development of stuttering treatment outcome measures and stuttering treatments
Authors: Onslow Mark
Published: May 2006

Background: The development of evidence‐based practice, which is increasingly popular in stuttering treatment, is closely linked to the development of outcome measures.

Aims: Two approaches to the development of stuttering treatment outcome measures are outlined. The first is the deductive, top‐down approach, where the development of specific outcome measures is guided by a priori general conceptualizations of the nature of the disorder. A competing approach to the development of stuttering treatment outcome measures is outlined. This is the inductive, or bottom up approach. This approach uses Baer's (1988, 1990) notion of specific complaints of clients as the starting point to develop inductive statements for use as general guidance for developing treatment outcome measures.

Main Contribution: It is argued that the deductive approach to development of outcome measures has limitations. It is overly prescriptive, generating numerous and increasingly complex outcome measures that are potentially confusing for clinicians. Further, it is arbitrary and fragile, being linked to conceptualizations and theories about stuttering, which, by necessity, are limited themselves. Further, the development of numerous outcome measures is not compatible with the conduct of randomized controlled trials, which allow a maximum of two primary outcome measures. In contrast, the inductive approach to the development of outcome measures has in its favour that it is empirically driven rather than arbitrary, and that it facilitates a yoking of the development of clinical outcomes and the clinical methods to attain those outcomes. The approach is unlikely to lead to the development of fruitless treatment methods. Further, the approach is parsimonious to the extent that it is likely to produce few guiding generalities for treatment outcome assessment — perhaps as few as two in the case of adults and one in the case of preschoolers. This is well suited to the use of the randomized controlled trial as a source of evidence for treatment efficacy.

Conclusions: One inductive statement that can be used to guide the development of outcome measures is that the ill effects of stuttered speech could be troubling for those who seek clinical help. The other is that those who seek clinical help are likely to experience speech‐related anxiety. Together, these sources of information provide sound guidance for the development of outcome measures relating to stuttered speech and speech‐related anxiety, and guidance for the development of treatments to offset those ill effects of the condition. Until another outcome measure can be derived from inductive processes, those treatment developments should serve all the needs of those who stutter and the clinicians who provide those needs.
The clathrin adaptor complex 1 directly binds to a sorting signal in Ste13p to reduce the rate of its trafficking to the late endosome of yeast
Authors: Foote Christopher , Nothwehr Steven F.
Published: May 2006

Yeast trans-Golgi network (TGN) membrane proteins maintain steady-state localization by constantly cycling to and from endosomes. In this study, we examined the trafficking itinerary and molecular requirements for delivery of a model TGN protein A(F→A)–alkaline phosphatase (ALP) to the prevacuolar/endosomal compartment (PVC). A(F→A)-ALP was found to reach the PVC via early endosomes (EEs) with a half-time of ∼60 min. Delivery of A(F→A)-ALP to the PVC was not dependent on either the GGA or adaptor protein 1 (AP-1) type of clathrin adaptors, which are thought to function in TGN to PVC and TGN to EE transport, respectively. Surprisingly, in cells lacking the function of both GGA and AP-1 adaptors, A(F→A)-ALP transport to the PVC was dramatically accelerated. A 12-residue cytosolic domain motif of A(F→A)-ALP was found to mediate direct binding to AP-1 and was sufficient to slow TGN→EE→PVC trafficking. These results suggest a model in which this novel sorting signal targets A(F→A)-ALP into clathrin/AP-1 vesicles at the EE for retrieval back to the TGN.
M line–deficient titin causes cardiac lethality through impaired maturation of the sarcomere
Authors: Weinert Stefanie , Bergmann Nora , Luo Xiuju , Erdmann Bettina , Gotthardt Michael
Published: May 2006

Titin, the largest protein known to date, has been linked to sarcomere assembly and function through its elastic adaptor and signaling domains. Titin's M-line region contains a unique kinase domain that has been proposed to regulate sarcomere assembly via its substrate titin cap (T-cap). In this study, we use a titin M line–deficient mouse to show that the initial assembly of the sarcomere does not depend on titin's M-line region or the phosphorylation of T-cap by the titin kinase. Rather, titin's M-line region is required to form a continuous titin filament and to provide mechanical stability of the embryonic sarcomere. Even without titin integrating into the M band, sarcomeres show proper spacing and alignment of Z discs and M bands but fail to grow laterally and ultimately disassemble.

The comparison of disassembly in the developing and mature knockout sarcomere suggests diverse functions for titin's M line in embryonic development and the adult heart that not only involve the differential expression of titin isoforms but also of titin-binding proteins.
Vascular endothelial growth factor is an important determinant of sepsis morbidity and mortality
Authors: Yano Kiichiro , Liaw Patricia C. , Mullington Janet M. , Shih Shu-Ching , Okada Hitomi , Bodyak Natalya , Kang Peter M. , Toltl Lisa , Belikoff Bryan , Buras Jon , Simms Benjamin T. , Mizgerd Joseph P. , Carmeliet Peter , Karumanchi S. Ananth , Aird William C.
Published: May 2006

Sepsis, the systemic inflammatory response to infection, is a leading cause of morbidity and mortality. The mechanisms of sepsis pathophysiology remain obscure but are likely to involve a complex interplay between mediators of the inflammatory and coagulation pathways. An improved understanding of these mechanisms should provide an important foundation for developing novel therapies. In this study, we show that sepsis is associated with a time-dependent increase in circulating levels of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) in animal and human models of sepsis. Adenovirus-mediated overexpression of soluble Flt-1 (sFlt-1) in a mouse model of endotoxemia attenuated the rise in VEGF and PlGF levels and blocked the effect of endotoxemia on cardiac function, vascular permeability, and mortality. Similarly, in a cecal ligation puncture (CLP) model, adenovirus–sFlt-1 protected against cardiac dysfunction and mortality. When administered in a therapeutic regimen beginning 1 h after the onset of endotoxemia or CLP, sFlt peptide resulted in marked improvement in cardiac physiology and survival. Systemic administration of antibodies against the transmembrane receptor Flk-1 but not Flt-1 protected against sepsis mortality. Adenovirus-mediated overexpression of VEGF but not PlGF exacerbated the lipopolysaccharide-mediated toxic effects. Together, these data support a pathophysiological role for VEGF in mediating the sepsis phenotype.
The Antibacterial Activity of Human Neutrophils and Eosinophils Requires Proton Channels but Not BK Channels
Authors: Femling Jon K. , Cherny Vladimir V. , Morgan Deri , Rada Balázs , Davis A. Paige , Czirják Gabor , Enyedi Peter , England Sarah K. , Moreland Jessica G. , Ligeti Erzsébet , Nauseef William M. , DeCoursey Thomas E.
Published: May 2006

Electrophysiological events are of central importance during the phagocyte respiratory burst, because NADPH oxidase is electrogenic and voltage sensitive. We investigated the recent suggestion that large-conductance, calcium-activated K+ (BK) channels, rather than proton channels, play an essential role in innate immunity (Ahluwalia, J., A. Tinker, L.H. Clapp, M.R. Duchen, A.Y. Abramov, S. Page, M. Nobles, and A.W. Segal. 2004. Nature. 427:853–858). In PMA-stimulated human neutrophils or eosinophils, we did not detect BK currents, and neither of the BK channel inhibitors iberiotoxin or paxilline nor DPI inhibited any component of outward current. BK inhibitors did not inhibit the killing of bacteria, nor did they affect NADPH oxidase-dependent degradation of bacterial phospholipids by extracellular gIIA-PLA2 or the production of superoxide anion (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{O}_{2^{.}}^{{-}}\) \end{document}). Moreover, an antibody against the BK channel did not detect immunoreactive protein in human neutrophils. A required role for voltage-gated proton channels is demonstrated by Zn2+ inhibition of NADPH oxidase activity assessed by H2O2 production, thus validating previous studies showing that Zn2+ inhibited \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{O}_{2^{.}}^{{-}}\) \end{document} production when assessed by cytochrome c reduction. In conclusion, BK channels were not detected in human neutrophils or eosinophils, and BK inhibitors did not impair antimicrobial activity. In contrast, we present additional evidence that voltage-gated proton channels serve the essential role of charge compensation during the respiratory burst.
Ca2+-activated Cl− Current from Human Bestrophin-4 in Excised Membrane Patches
Authors: Tsunenari Takashi , Nathans Jeremy , Yau King-Wai
Published: May 2006

Bestrophins are a newly discovered family of Cl− channels, some members of which are activated by intracellular Ca2+. So far, all studies were carried out with whole-cell recordings from plasmid-transfected cultured cells, so it is unclear whether Ca2+ activates bestrophin through a metabolic mechanism or in a more direct way. We report here experiments that addressed this question with excised, inside-out membrane patches. We chose human bestrophin-4 (hBest4) for heterologous expression because it gave particularly large Cl− currents when expressed, thus allowing detection even in excised membrane patches. hBest4 gave a negligible Cl− current in a Ca2+-free solution on the cytoplasmic (bath) side, but produced a Cl− current that was activated by Ca2+ in a dose-dependent manner, with a K1/2 of 230 nM. Thus, Ca2+ appears to activate the bestrophin Cl− channel without going through a freely diffusible messenger or through protein phosphorylation. Because the activation and deactivation kinetics were very slow, however, we cannot exclude the involvement of a membrane-associated messenger.
Widespread genome duplications throughout the history of flowering plants
Authors: Cui Liying , Wall P. Kerr , Leebens-Mack James H. , Lindsay Bruce G. , Soltis Douglas E. , Doyle Jeff J. , Soltis Pamela S. , Carlson John E. , Arumuganathan Kathiravetpilla , Barakat Abdelali , Albert Victor A. , Ma Hong , dePamphilis Claude W.
Published: May 2006

Genomic comparisons provide evidence for ancient genome-wide duplications in a diverse array of animals and plants. We developed a birth–death model to identify evidence for genome duplication in EST data, and applied a mixture model to estimate the age distribution of paralogous pairs identified in EST sets for species representing the basal-most extant flowering plant lineages. We found evidence for episodes of ancient genome-wide duplications in the basal angiosperm lineages including Nuphar advena (yellow water lily: Nymphaeaceae) and the magnoliids Persea americana (avocado: Lauraceae), Liriodendron tulipifera (tulip poplar: Magnoliaceae), and Saruma henryi (Aristolochiaceae). In addition, we detected independent genome duplications in the basal eudicot Eschscholzia californica (California poppy: Papaveraceae) and the basal monocot Acorus americanus (Acoraceae), both of which were distinct from duplications documented for ancestral grass (Poaceae) and core eudicot lineages. Among gymnosperms, we found equivocal evidence for ancient polyploidy in Welwitschia mirabilis (Gnetales) and no evidence for polyploidy in pine, although gymnosperms generally have much larger genomes than the angiosperms investigated. Cross-species sequence divergence estimates suggest that synonymous substitution rates in the basal angiosperms are less than half those previously reported for core eudicots and members of Poaceae. These lower substitution rates permit inference of older duplication events. We hypothesize that evidence of an ancient duplication observed in the Nuphar data may represent a genome duplication in the common ancestor of all or most extant angiosperms, except Amborella.
Very little intron loss/gain in Plasmodium: Intron loss/gain mutation rates and intron number
Authors: Roy Scott William , Hartl Daniel L.
Published: May 2006

We compared intron positions in conserved regions of 3479 orthologous gene pairs from Plasmodium falciparum and Plasmodium yoelii, which likely diverged ≥100 million years ago (Mya). Only 27 out of 2212 positions were specific to one of the two species. Intron presence in related species shows that at least 19 and possibly 26 of the changes are due to intron loss, depending on phylogeny. The implied intron loss and gain rates are much lower than previously estimated for nematodes, arthropods, fungi, and plants, and are comparable only with the rates in vertebrates. That all observed changes were exact, occurring without loss or gain of flanking coding sequence, suggests intron loss via an mRNA intermediate, as does a nonsignificant trend toward loss of introns at adjacent positions. Many of the intron changes occurred in genes encoding proteins involved in nucleic acid-related processes, as previously found for intron gains in nematodes. Two changes occurred in the chloroquine resistance transporter, suggesting a role for positive selection in intron loss in Plasmodium. The dearth of intron loss and gain could be explained by the lack of known transposable elements in Plasmodium, since transposable elements and/or reverse transcriptase are thought to be necessary for both processes. The observed pattern suggests that the availability of stochastic intron loss and gain mutations can be a major determinant of changes in intron number.
False Remembering in the Aged
Authors: Jacoby Larry L. , Rhodes Matthew G.
Published: May 2006

Researchers studying human memory have increasingly focused on memory accuracy in aging populations. In this article we briefly review the literature on memory accuracy in healthy older adults. The prevailing evidence indicates that, compared to younger adults, older adults exhibit both diminished memory accuracy and greater susceptibility to misinformation. In addition, older adults demonstrate high levels of confidence in their false memories. We suggest an explanatory framework for the high level of false memories observed in older adults, a framework based on the theory that consciously controlled uses of memory decline with age, making older adults more susceptible to false memories that rely on automatic processes. We also point to future research that may remedy such deficits in accuracy.
Infants' Differential Processing of Female and Male Faces
Authors: Ramsey-Rennels Jennifer L. , Langlois Judith H.
Published: May 2006

Infants show an interesting asymmetry in face processing: They are more fluent in processing female faces than they are at processing male faces. We hypothesize that such processing asymmetry results from greater experience with female faces than with male faces early in development. Asymmetrical face processing may have long-lasting implications for development of face recognition, development of knowledge structures regarding females and males, and social-information processing. We encourage researchers to use both female and male faces in their face-perception research and to conduct separate analyses for female and male faces.
Learning in High-Tech and Multimedia Environments
Authors: Moreno Roxana
Published: May 2006

When do high-tech environments promote learning? The goal of this article is to offer one answer to this question by examining the classic distinction between media and method, in terms of their roles in promoting learning with technology. To this end, I first propose a cognitive theory of learning with media, from which a set of instructional design principles are derived. Then I review research in which the relative learning contributions of method and media are investigated, and I offer final reflections for future research.
The Structure of Emotion
Authors: Barrett Lisa Feldman , Wager Tor D.
Published: May 2006

One common point of debate in the study of emotion is whether the basic, irreducible elements of emotional life are discrete emotion categories, such as anger, fear, sadness, and so on, or dimensions such as approach and avoidance. Resolving this debate will identify the basic building blocks of emotional life that are the most appropriate targets of scientific inquiry. In this paper, we briefly review meta-analytic work on the neuroimaging of emotion and examine its potential for identifying “natural kinds” of emotion in the brain. We outline criteria for identifying such natural kinds, summarize the evidence to date on category and dimensional approaches, and suggest ways in which neuroimaging studies could more directly address fundamental questions about the nature of emotion.
Attentional Limitations in Doing Two Tasks at Once
Authors: Lien Mei-Ching , Ruthruff Eric , Johnston James C.
Published: May 2006

People generally have difficulty doing two tasks at once. To explain this fact, theorists have proposed that central processing—the thought-like stages following perceptual encoding and preceding response processing—takes place for only one task at a time. Because this bottleneck imposes severe limits on human cognitive processes, research has attempted to find exceptions. There is now solid evidence that, at least in the laboratory, the entire bottleneck can be completely bypassed under favorable combinations of circumstances. While these findings provide a ray of hope for enabling parallel multitasking in real-world scenarios, it will not be easy to take advantage of the combination of conditions that appear to be necessary.
As Others See Us
Authors: Achenbach Thomas M.
Published: May 2006

Discrepancies are often found between self-reports and reports by others regarding psychopathology. Both the person being assessed and various informants may contribute crucial data concerning a person's functioning. Comprehensive assessment requires data from multiple informants. Such data can be easily obtained with parallel self-report and collateral-report forms. The multi-informant data can be compared, aggregated, and used in many ways. Optimal use of multi-source data is essential for clinical assessment and for discovering causes and cures of psychopathology.
Radiation hybrid mapping of 18 positional and physiological candidate genes for arthrogryposis multiplex congenita on porcine chromosome 5
Authors: Genini S. , Nguyen T. T. , Malek M. , Talbot R. , Gebert S. , Rohrer G. , Nonneman D. , Stranzinger G. , Vögeli P.
Published: May 2006

We report the chromosomal assignment of 18 porcine genes to human homologues using the INRA‐Minnesota swine radiation hybrid panel (IMpRH). These genes (CACNA1C, COL2A1, CPNE8, C3F, C12ORF4, DDX11, GDF11, HOXC8, KCNA1, MDS028, TMEM106C, NR4A1, PHB2, PRICKLE1, Q6ZUQ4, SCN8A, TUBA8 and USP18) are located on porcine chromosome 5 (SSC5) and represent positional and functional candidates for arthrogryposis multiplex congenita (AMC), which maps to SSC5. CPNE8, PRICKLE1, Q6ZUQ4 and TUBA8 were mapped to the interval for pig AMC between microsatellites SW152 and SW904. Three SNPs in TUBA8 co‐segregated with the AMC phenotype in 230 pigs of our research population without recombination and could be used as a genetic marker test for AMC. In addition, we provide evidence that a small chromosomal region of HSA22q11.2 evolutionarily corresponds to SSC5q12–q22 (and contains the human homologues of porcine SW152, Q6ZUQ4, TUBA8 and USP18), while the regions flanking HSA22q11.2 on SSC5 correspond to HSA12p13 and HSA12q12. We identified seven distinct chromosomal blocks, further supporting extensive rearrangements between genes on HSA12 and HSA22 in the AMC region on SSC5.
Estimation of the number of genetic markers required for individual animal identification accounting for genotyping errors
Authors: Weller J. I. , Seroussi E. , Ron M.
Published: May 2006

Nearly all studies that consider the power of exclusion for individual identification using genetic markers ignore the possibility of erroneous genotypes, although individual genotype error rates are approximately 1% for microsatellites. Single nucleotide polymorphisms (SNPs) have lower error rates, but because of their lower information content, more SNPs than microsatellites will be required to obtain the same power of exclusion for traceability. In this study, we accounted for genotyping mistakes by requiring at least two discrepancies to reject a match. Exclusion probabilities were computed analytically and by simulation. A microsatellite with five alleles was approximately comparable in exclusion power to 2–2.25 SNPs. At least eight SNPs were required to achieve a 99% probability of rejection for a match between two individuals, while with 25 SNPs there was a <1% chance for a match between any of five million individuals.
The Tabby cat locus maps to feline chromosome B1
Authors: Lyons L. A. , Bailey S. J. , Baysac K. C. , Byrns G. , Erdman C. A. , Fretwell N. , Froenicke L. , Gazlay K. W. , Geary L. A. , Grahn J. C. , Grahn R. A. , Karere G. M. , Lipinski M. J. , Rah H. , Ruhe M. T. , Bach L. H.
Published: May 2006

The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (T a‐) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, θ = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17‐cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats.
Changing sources of soil respiration with time since fire in a boreal forest
Authors: CZIMCZIK CLAUDIA I. , TRUMBORE SUSAN E. , CARBONE MARIAH S. , WINSTON GREGORY C.
Published: May 2006

Radiocarbon signatures (Δ14C) of carbon dioxide (CO2) provide a measure of the age of C being decomposed by microbes or respired by living plants. Over a 2‐year period, we measured Δ14C of soil respiration and soil CO2 in boreal forest sites in Canada, which varied primarily in the amount of time since the last stand‐replacing fire. Comparing bulk respiration Δ14C with Δ14C of CO2 evolved in incubations of heterotrophic (decomposing organic horizons) and autotrophic (root and moss) components allowed us to estimate the relative contributions of O horizon decomposition vs. plant sources. Although soil respiration fluxes did not vary greatly, differences in Δ14C of respired CO2 indicated marked variation in respiration sources in space and time.

The 14C signature of respired CO2 respired from O horizon decomposition depended on the age of C substrates. These varied with time since fire, but consistently had Δ14C greater (averaging ∼120‰) than autotrophic respiration. The Δ14C of autotrophically respired CO2 in young stands equaled those expected for recent photosynthetic products (70‰ in 2003, 64‰ in 2004). CO2 respired by black spruce roots in stands >40 years old had Δ14C up to 30‰ higher than recent photosynthates, indicating a significant contribution of C stored at least several years in plants.

Decomposition of O horizon organic matter made up 20% or less of soil respiration in the younger (<40 years since fire) stands, increasing to ∼50% in mature stands. This is a minimum for total heterotrophic contribution, since mineral soil CO2 had Δ14C close to or less than those we have assigned to autotrophic respiration. Decomposition of old organic matter in mineral soils clearly contributed to soil respiration in younger stands in 2003, a very dry year, when Δ14C of soil respiration in younger successional stands dropped below those of the atmospheric CO2.
Trends and methodological impacts in soil CO2 efflux partitioning: A metaanalytical review
Authors: SUBKE JENS‐ARNE , INGLIMA ILARIA , FRANCESCA COTRUFO M.
Published: May 2006

Partitioning soil carbon dioxide (CO2) efflux (RS) into autotrophic (RA; including plant roots and closely associated organisms) and heterotrophic (RH) components has received considerable attention, as differential responses of these components to environmental change have profound implications for the soil and ecosystem C balance. The increasing number of partitioning studies allows a more detailed analysis of experimental constraints than was previously possible. We present results of an exhaustive literature search of partitioning studies and analyse global trends in flux partitioning between biomes and ecosystem types by means of a metaanalysis. Across all data, an overall decline in the RH/RS ratio for increasing annual RS fluxes emerged. For forest ecosystems, boreal coniferous sites showed significantly higher (P<0.05) RH/RS ratios than temperate sites, while both temperate or tropical deciduous forests did not differ in ratios from any of the other forest types. While chronosequence studies report consistent declines in the RH/RS ratio with age, no difference could be detected for different age groups in the global data set. Different methodologies showed generally good agreement if the range of RS under which they had been measured was considered, with the exception of studies estimating RH by means of root mass regressions against RS, which resulted in consistently lower RH/RS estimates out of all methods included. Additionally, the time step over which fluxes were partitioned did not affect RH/RS ratios consistently. To put results into context, we review the most common techniques and point out the likely sources of errors associated with them. In order to improve soil CO2 efflux partitioning in future experiments, we include methodological recommendations, and also highlight the potential interactions between soil components that may be overlooked as a consequence of the partitioning process itself.
Stand age‐related effects on soil respiration in a first rotation Sitka spruce chronosequence in central Ireland
Authors: SAIZ GUSTAVO , BYRNE KENNETH A. , BUTTERBACH‐BAHL KLAUS , KIESE RALF , BLUJDEA VIOREL , FARRELL EDWARD P.
Published: May 2006

The effect of stand age on soil respiration and its components was studied in a first rotation Sitka spruce chronosequence composed of 10‐, 15‐, 31‐, and 47‐year‐old stands established on wet mineral gley in central Ireland. For each stand age, three forest stands with similar characteristics of soil type and site preparation were used. There were no significant differences in total soil respiration among sites of the same age, except for the case of a 15‐year‐old stand that had lower soil respiration rates due to its higher productivity. Soil respiration initially decreased with stand age, but levelled out in the older stands. The youngest stands had significantly higher respiration rates than more mature sites. Annual soil respiration rates were modelled by means of temperature‐derived functions. The averageQ10value obtained treating all the stands together was 3.8. Annual soil respiration rates were 991, 686, 556, and 564 g C m−2for the 10‐, 15‐, 31‐, and 47‐year‐old stands, respectively. We used the trenching approach to separate soil respiration components. Heterotrophic respiration paralleled soil organic carbon dynamics over the chronosequence, decreasing with stand age to slightly increase in the oldest stand as a result of accumulated aboveground litter and root inputs. Root respiration showed a decreasing trend with stand age, which was explained by a decrease in fine root biomass over the chronosequence, but not by nitrogen concentration of fine roots. The decrease in the relative contribution of autotrophic respiration to total soil CO2efflux from 59.3% in the youngest stand to 49.7% in the oldest stand was explained by the higher activity of the root system in younger stands. Our results show that stand age should be considered if simple temperature‐based models to predict annual soil respiration in afforestation sites are to be used.
The hydrophilic, foaming and emulsifying properties of casein concentrates produced by various methods
Authors: Roman Janesca A. , Sgarbieri Valdemiro C.
Published: May 2006

The hydrophilic and surfactant properties of casein concentrates made by different processes such as isoelectric precipitation and neutralization (commercial casein, CC) coagulation by rennet (casein clots, COC) and microfiltration/diafiltration (casein micelles, CM) were studied. Water absorption capacity (WAC), water solubility (WS) and water‐holding capacity (WHC) were highest for CM and lowest for COC. Solubility was higher in water and in pH 5.5, 0.10 m NaCl solution for both CM and COC. Foaming capacity was better for CM than for CC at pH 4.0 and for CC at pH 6.0 and 8.0. Foam stability was low for both CM and CC at pH 4.0 but it was high for CM at pH 6.0 and 8.0 and for CC in the absence of salt. Emulsifying capacity was higher for CC at pH 4.0 and 7.0. Stability of emulsion was high for CC at pH 4.0 and for CM at pH 7.0.
Evaluation of zinc and magnesium bioavailability from pea (Pisum sativum, L.) sprouts. Effect of illumination and different germination periods
Authors: Urbano Gloria , López‐Jurado María , Aranda Carlos , Vilchez Antonio , Cabrera Lydia , Porres Jesus M. , Aranda Pilar
Published: May 2006

The effect of sprouting pea seeds (Pisum sativum, L) for 2, 4 and 6 days, with and without light, on the content of zinc (Zn) and magnesium (Mg) and their nutritive utilisation by growing rats was studied. Soaking of pea seeds prior to germination caused a 49% reduction in Zn content followed by minor losses during germination. The content of Mg decreased by 6% as a result of the soaking process, and by 20–28% during germination. Sprouting for 2 and 4 days improved the bioavailability of Zn and Mg from pea seeds (from 32.2 to 88.6–108.0 μg retained Zn per day, and from 1.64 to 2.97–4.79 mg retained Mg per day in raw and sprouted pea flour diets, respectively), outweighing the reductions in Zn and Mg content because of seed soaking. The presence or absence of light during the germination process did not affect the results. We conclude that sprouting of peas for 4 days was the most effective treatment to improve the bioavailability of Zn and Mg in pea seeds.
Shelf‐life of a dragee product based on sunflower kernel depending on packaging materials used
Authors: Pajin Biljana , Lazic Vera , Jovanovic Olga , Gvozdenovic Jasna
Published: May 2006

In this study, we investigated the quality and shelf‐life of a dragee product obtained by coating a confectionery sunflower kernel with sugar syrup. The product was packed in oriented polypropylene/oriented polypropylene, oriented polypropylene/metallised oriented polypropylene, polyester/polyethylene and kept at room temperature in daylight for 5 months. At the beginning of the experiment, the dragee product was in the category of excellent sensory quality (total score of sensory evaluation is between 18.0 and 20.0) in terms of its colour, smell, taste, mastication and structure. During the storage, these properties changed and the product lost its stability. Peroxide value in the dragee product increased from 0.5 to 9.0 mmol O/kg during the 5 months of storage. The free fatty acid content also increased from 1.3% in fresh dragee product to 2.5% after 5 months of storage. The packaging material metallised polyester/polyethylene, labelled metPET/PE, has the lowest oxygen permeability (8.0 mL m−2/dan Δp 1 bar) and because of this it had the strongest influence in the prevention of hydrolytic and oxidative changes in the final product.
Floristic patterns and plant traits of Mediterranean communities in fragmented habitats
Authors: Chust Guillem , Pérez‐Haase Aaron , Chave Jérôme , Pretus Joan Ll.
Published: May 2006

Aim  To contrast floristic spatial patterns and the importance of habitat fragmentation in two plant communities (grassland and scrubland) in the context of ecological succession. We ask whether plant assemblages are affected by habitat fragmentation and, if so, at what spatial scale? Does the relative importance of the niche differentiation and dispersal‐limitation mechanisms change throughout secondary succession? Is the dispersal‐limitation mechanism related to plant functional traits?

Location  A Mediterranean region, the massif of Albera (Spain).

Methods  Using a SPOT satellite image to describe the landscape, we tested the effect of habitat fragmentation on species composition, determining the spatial scale of the assemblage response. We then assessed the relative importance of dispersal‐related factors (habitat fragmentation and geographical distance) and environmental constraints (climate‐related variables) influencing species similarity. We tested the association between dispersal‐related factors and plant traits (dispersal mode and life form).

Results  In both community types, plant composition was partially affected by the surrounding vegetation. In scrublands, animal‐dispersed and woody plants were abundant in landscapes dominated by closed forests, whereas wind‐dispersed annual herbs were poorly represented in those landscapes. Scrubby assemblages were more dependent on geographical distance, habitat fragmentation and climate conditions (temperature, rainfall and solar radiation); grasslands were described only by habitat fragmentation and rainfall. Plant traits did not explain variation in spatial structuring of assemblages.

Main conclusions  Plant establishment in early Mediterranean communities may be driven primarily by migration from neighbouring established communities, whereas the importance of habitat specialization and community drift increases over time. Plant life forms and dispersal modes did not explain the spatial variation of species distribution, but species richness within the community with differing plant traits was affected by habitat patchiness.
Calcium and vitamin D in the prevention and treatment of osteoporosis – a clinical update
Authors: BOONEN S. , VANDERSCHUEREN D. , HAENTJENS P. , LIPS P.
Published: May 2006

Combined calcium and vitamin D supplementation is an essential component of the management of osteoporosis, supported by a strong scientific rationale. The types of individuals who should receive calcium and vitamin D supplements are those: (i) patients with documented osteoporosis receiving antiresorptive or anabolic treatment; (ii) patients receiving glucocorticoids; and (iii) individuals with or at high risk of calcium and/or vitamin D insufficiencies, in particular older women and men. This article describes the evidence base that supports targeting these groups. Benefits are most apparent when 800 IU day−1 vitamin D is complemented with a dose of 1000–1200 mg day−1 elemental calcium. Compliance is also key to optimizing clinical efficacy.
Sleep Beliefs Scale (SBS) and circadian typology
Authors: ADAN ANA , FABBRI MARCO , NATALE VINCENZO , PRAT GEMMA
Published: May 2006

The aim of this work was to present the Sleep Beliefs Scale (SBS), a 20‐item reviewed version of the Sleep Hygiene Awareness by Lacks and Rotert [Behav. Res. Ther., 1986, 28: 104–112]. We also examined for the first time the influence of circadian typology in sleep beliefs. Voluntary and unpaid psychology students participated in the study (n = 510; 182 men and 328 women), from Italy and Spain, aged between 18 and 33 (22.80 ± 4.14 years). The mean score of SBS was 13.05 (SD = 3.46; range 2–20) in the total sample, with a distribution positive skewness to high score (correct beliefs) (Z = 1.82; P = 0.003). The internal consistency was good (Cronbach's α = 0.714) and factor analysis extracted three factors labelled ‘Sleep‐incompatible behaviours’ (eight items), ‘Sleep–wake cycle behaviours’ (seven items) and ‘Thoughts and attitudes to sleep’ (five items). Circadian typology influences the total score and that of the three factors, as well the majority of the items that compose the SBS. The morning‐type showed the best scores, the evening‐type the worst, and the neither‐type the medium scores. Moreover, in the men sample, the differences between circadian typology groups were higher than in the women sample. The SBS showed good psychometric properties; however, further studies in other countries, with clinical and non‐student samples, and more aged subjects are needed so as to validate this psychometric instrument. The circadian typology is an individual difference that presented significant relationships with the sleep beliefs, the possibility of the evening‐type being a risk factor for a worse sleep hygiene, and the maintenance of sleep problems such as insomnia may all be investigated in depth in future research.
Timing of spontaneous sleep‐paralysis episodes
Authors: GIRARD TODD A. , CHEYNE J. ALLAN
Published: May 2006

The objective of this prospective naturalistic field study was to determine the distribution of naturally occurring sleep‐paralysis (SP) episodes over the course of nocturnal sleep and their relation to bedtimes. Regular SP experiencers (N = 348) who had previously filled out a screening assessment for SP as well as a general sleep survey were recruited. Participants reported, online over the World Wide Web, using a standard reporting form, bedtimes and subsequent latencies of spontaneous episodes of SP occurring in their homes shortly after their occurrence. The distribution of SP episodes over nights was skewed to the first 2 h following bedtime. Just over one quarter of SP episodes occurred within 1 h of bedtime, although episodes were reported throughout the night with a minor mode around the time of normal waking. SP latencies following bedtimes were moderately consistent across episodes and independent of bedtimes. Additionally, profiles of SP latencies validated self‐reported hypnagogic, hypnomesic, and hypnopompic SP categories, as occurring near the beginning, middle, and end of the night/sleep period respectively. Results are consistent with the hypothesis that SP timing is controlled by mechanisms initiated at or following sleep onset. These results also suggest that SP, rather than uniquely reflecting anomalous sleep‐onset rapid eye movement (REM) periods, may result from failure to maintain sleep during REM periods at any point during the sleep period. On this view, SP may sometimes reflect the maintenance of REM consciousness when waking and SP hallucinations the continuation of dream experiences into waking life.
Adaptive servo‐ventilation and deadspace: effects on central sleep apnoea
Authors: SZOLLOSI I. , O'DRISCOLL D. M. , DAYER M. J. , COATS A. J. , Morrell M. J. , Simonds A. K.
Published: May 2006

Central Sleep Apnoea (CSA) occurs commonly in heart failure. Adaptive servo‐ventilation (ASV) and deadspace (DS) have been shown in research settings to reverse CSA. The likely mechanism for this is the increase of PaCO2 above the apnoeic threshold. However the role of increasing FiCO2 on arousability remains unclear. To compare the effects of ASV and DS on sleep and breathing, in particular effects on Arousal Index (ArI), ten male patients with heart failure and CSA were studied during three nights with polysomnography plus measurements of PetCO2. The order of the interventions control (C), ASV and DS was randomized. ASV and DS caused similar reductions in apnoea–hypopnoea index [(C) 30.0 ± 6.6, (ASV) 14.0 ± 3.8, (DS) 15.9 ± 4.7 e h−1; both P < 0.05]. However, DS was associated with decreased total sleep time compared with C (P < 0.02) and increased spontaneous ArI compared to C and ASV (both P < 0.01). Only DS was associated with increased ΔPetCO2 from resting wakefulness to eupnic sleep [(C) 2.1  ± 0.9, (ASV) 1.3 ± 1.0, (DS) 5.6 ± 0.5 mmHg; P = 0.01]. ASV and DS both stabilized ventilation however DS application also increased sleep fragmentation with negative impacts on sleep architecture. We speculate that this effect is likely to be mediated by increased PetCO2 and respiratory effort associated with DS application.
Subjective sleepiness and accident risk avoiding the ecological fallacy
Authors: INGRE MICHAEL , ÅKERSTEDT TORBJÖRN , PETERS BJÖRN , ANUND ANNA , KECKLUND GÖRAN , PICKLES ANDREW
Published: May 2006

The present study of sleepiness and accident risk in a HI‐FI car simulator aimed to provide subject‐level relative risks (RR) with 95% confidence intervals (CI) for different levels of subjective sleepiness measured with the Karolinska Sleepiness Scale (KSS), 1 = very alert, 9 = very sleepy, fighting sleep, an effort to staying awake. Five male and five female shift workers, mean age 37 years, participated with a 2‐h drive (08:00–10:00 hours) in a dynamic high‐fidelity moving base driving simulator, after a night of work and after a night of sleep. Subjective sleepiness was measured with KSS every 5 min and events of incidents (two wheels outside the right lane), accidents (two wheels off the road or four wheels in opposite lane) and crashes (four wheels off the road) were recorded. The probability of an accident was modelled with a Generalized Linear Mixed Model approach to estimate subject‐specific effects, rather than group average effects, to avoid the ecological fallacy. The results showed that sleepiness was strongly related to accident risk. An average subject was estimated at 28.2 times (95% CI RR = 10.7–74.1) increased risk at KSS = 8 and at 185 times (95% CI RR = 42–316) at KSS = 9 compared with KSS = 5. There were large individual differences in event propensity that complicates the prediction of absolute accident risk for individual subjects.
Individualized and time‐variant model for the functional link between thermoregulation and sleep onset
Authors: QUANTEN STIJN , DE VALCK ELKE , CLUYDTS RAYMOND , AERTS JEAN‐MARIE , BERCKMANS DANIEL
Published: May 2006

This study makes use of control system model identification techniques to examine the relationship between thermoregulation and sleep regulation. Specifically, data‐based mechanistic (DBM) modelling is used to formulate and experimentally test the hypothesis, put forth by Gilbertet al.[Sleep Med. Rev.8(2004) 81], that there exists a connection between distal heat loss and sleepiness. Six healthy sleepers each spent three nights and the following day in the sleep laboratory: an adaptation, a cognitive arousal and a neutral testing day. In the cognitive arousal condition, a visit of a television camera crew took place and subjects were asked to be interviewed. During each of the three 25‐min driving simulator tasks per day, the distal‐to‐proximal gradient and the electroencephalogram are recorded. It is observed from these experimental data that there exists a feedback connection between thermoregulation and sleep. In addition to providing experimental evidence in support of theGilbertet al.(2004)hypothesis, the authors propose that the nature of the feedback connection is determined by the nature of sleep/wake state (i.e. NREM sleep versus unwanted sleepiness in active subjects). Besides this, an individualized and time‐variant model for the linkage between thermoregulation and sleep onset is presented. This compact model feeds on real‐time data regarding distal heat loss and sleepiness and contains a physically meaningful parameter that delivers an individual‐ and time‐depending quantification of a well known biological features in the field of thermoregulation: the thermoregulatory error signalThypo(t)−Tset(t). A validation of these physical/biological features emphasizes the reliability and power of DBM in describing individual differences related to the sleep process.
Sleepless night, the moon is bright: longitudinal study of lunar phase and sleep
Authors: RÖÖSLI MARTIN , JÜNI PETER , BRAUN‐FAHRLÄNDER CHARLOTTE , BRINKHOF MARTIN W. G. , LOW NICOLA , EGGER MATTHIAS
Published: May 2006

Popular belief holds that the lunar cycle affects human physiology, behaviour and health. We examined the influence of moon phase on sleep duration in a secondary analysis of a feasibility study of mobile telephone base stations and sleep quality. We studied 31 volunteers (18 women and 13 men, mean age 50 years) from a suburban area of Switzerland longitudinally over 6 weeks, including two full moons. Subjective sleep duration was calculated from sleep diary data. Data were analysed using multiple linear regression models with random effects. Mean sleep duration was 6 h 49 min. Subjective sleep duration varied with the lunar cycle, from 6 h 41 min at full moon to 7 h 00 min at new moon (P < 0.001). Average sleep duration was shortened by 68 min during the week compared with weekends (P < 0.001). Men slept 17 min longer than women (P < 0.001) and sleep duration decreased with age (P < 0.001). There was also evidence that rating of fatigue in the morning was associated with moon phase, with more tiredness (P = 0.027) at full moon. The study was designed for other purposes and the association between lunar cycle and sleep duration will need to be confirmed in further studies.