bluuebunny/crossref_metadata_2025 huggingface dataset:
Organic anions and potassium salts in nutrition and metabolism
Authors: Demigné Christian , Sabboh Houda , Puel Caroline , Rémésy Christian , Coxam Véronique
Published: December 2004

The present review examines the importance of dietary organic anions in preventive nutrition. Organic anions are chiefly supplied by plant foods, as partially neutralised K salts such as potassium citrate, potassium malate and, to a lesser extent, oxalate or tartrate salts. Animal products may also supply K anions, essentially as phosphate, but also as lactate as a result of fermentative or maturation processes, but these K salts have little alkalinising significance. Citrate and malate anions are absorbed in the upper digestive tract, while a substantial proportion is probably metabolised in the splanchnic area. Whatever their site of metabolism, these anions finally yield KHCO3which is used by the kidneys to neutralise fixed acidity. This acidity essentially reflects the oxidation of excess S amino acids to sulfate ions, which is mainly related to the dietary protein level. Failure to neutralise acidity leads to low-grade metabolic acidosis, with possible long-term deleterious effects on bone Ca status and on protein status. Furthermore, low-grade acidosis is liable to affect other metabolic processes, such as peroxidation of biological structures. These metabolic disturbances could be connected with the relatively high incidence of osteoporosis and muscle-protein wasting problems observed in ageing individuals in Europe and Northern America. Providing a sufficient supply of K organic anions through fruit and vegetable intake should be recommended, fostering the actual motivational campaigns ('five (or ten) per d') already launched to promote the intake of plant foods rich in complex carbohydrates and various micronutrients.
p73 induction after DNA damage is regulated by checkpoint kinases Chk1 and Chk2
Authors: Urist Marshall , Tanaka Tomoaki , Poyurovsky Masha V. , Prives Carol
Published: December 2004

The checkpoint kinases Chk1 and Chk2 are central to the induction of cell cycle arrest, DNA repair, and apoptosis as elements in the DNA-damage checkpoint. We report here that in several human tumor cell lines, Chk1 and Chk2 control the induction of the p53 related transcription factor p73 in response to DNA damage. Multiple experimental systems were used to show that interference with or augmentation of Chk1 or Chk2 signaling strongly impacts p73 accumulation. Furthermore, Chk1 and Chk2 control p73 mRNA accumulation after DNA damage. We demonstrate as well that E2F1 directs p73 expression in the presence and absence of DNA damage. Chk1 and Chk2, in turn, are vital to E2F1 stabilization and activity after genotoxic stress. Thus, Chk1, Chk2, E2F1, and p73 function in a pathway mediating p53-independent cell death produced by cytotoxic drugs. Since p53 is often obviated through mutation as a cellular port for anticancer intervention, this pathway controlling p53 autonomous pro-apoptotic signaling is of potential therapeutic importance.
Replication-dependent destruction of Cdt1 limits DNA replication to a single round per cell cycle in Xenopus egg extracts
Authors: Arias Emily E. , Walter Johannes C.
Published: December 2004

In eukaryotes, prereplication complexes (pre-RCs) containing ORC, Cdc6, Cdt1, and MCM2-7 are assembled on chromatin in the G1 phase. In S phase, when DNA replication initiates, pre-RCs are disassembled, and new pre-RC assembly is restricted until the following G1 period. As a result, DNA replication is limited to a single round per cell cycle. One inhibitor of pre-RC assembly, geminin, was discovered in Xenopus, and it binds and inactivates Cdt1 in S phase. However, removal of geminin from Xenopus egg extracts is insufficient to cause rereplication, suggesting that other safeguards against rereplication exist. Here, we show that Cdt1 is completely degraded by ubiquitin-mediated proteolysis during the course of the first round of DNA replication in Xenopus egg extracts. Degradation depends on Cdk2/Cyclin E, Cdc45, RPA, and polymerase α, demonstrating a requirement for replication initiation. Cdt1 is ubiquitinated on chromatin, and this process also requires replication initiation. Once replication has initiated, Cdk2/Cyclin E is dispensable for Cdt1 degradation. When fresh Cdt1 is supplied after the first round of DNA replication, significant rereplication results, and rereplication is enhanced in the absence of geminin. Our results identify a replication-dependent proteolytic pathway that targets Cdt1 and that acts redundantly with geminin to inactivate Cdt1 in S phase.
A Dicer-like protein in Tetrahymena has distinct functions in genome rearrangement, chromosome segregation, and meiotic prophase
Authors: Mochizuki Kazufumi , Gorovsky Martin A.
Published: December 2004

Previous studies indicated that genome rearrangement involving DNA sequence elimination that occurs at late stages of conjugation in Tetrahymena is epigenetically controlled by siRNA-like scan (scn) RNAs produced from nongenic, heterogeneous, bidirectional, micronuclear transcripts synthesized at early stages of conjugation. Here, we show that Dcl1p, one of three Tetrahymena Dicer-like enzymes, is required for processing the micronuclear transcripts to scnRNAs. DCL1 is also required for methylation of histone H3 at Lys 9, which, in wild-type cells, specifically occurs on the sequences (IESs) being eliminated. These results argue that Dcl1p processes nongenic micronuclear transcripts to scnRNAs and is required for IES elimination. This is the first evidence linking nongenic micronuclear transcripts, scnRNAs, and genome rearrangement. Dcl1p also is required for proper mitotic and meiotic segregation of micronuclear chromosomes and for normal chromosome alignment in meiotic prophase, suggesting that DCL1 has multiple functions in regulating chromosome dynamics.
UBF-binding site arrays form pseudo-NORs and sequester the RNA polymerase I transcription machinery
Authors: Mais Christine , Wright Jane E. , Prieto José-Luis , Raggett Samantha L. , McStay Brian
Published: December 2004

Human ribosomal genes (rDNA) are located in nucleolar organizer regions (NORs) on the short arms of acrocentric chromosomes. Metaphase NORs that were transcriptionally active in the previous cell cycle appear as prominent chromosomal features termed secondary constrictions that are achromatic in chromosome banding and positive in silver staining. The architectural RNA polymerase I (pol I) transcription factor UBF binds extensively across rDNA throughout the cell cycle. To determine if UBF binding underpins NOR structure, we integrated large arrays of heterologous UBF-binding sequences at ectopic sites on human chromosomes. These arrays efficiently recruit UBF even to sites outside the nucleolus and, during metaphase, form novel silver stainable secondary constrictions, termed pseudo-NORs, morphologically similar to NORs. We demonstrate for the first time that in addition to UBF the other components of the pol I machinery are found associated with sequences across the entire human rDNA repeat. Remarkably, a significant fraction of these same pol I factors are sequestered by pseudo-NORs independent of both transcription and nucleoli. Because of the heterologous nature of the sequence employed, we infer that sequestration is mediated primarily by protein–protein interactions with UBF. These results suggest that extensive binding of UBF is responsible for formation and maintenance of the secondary constriction at active NORs. Furthermore, we propose that UBF mediates recruitment of the pol I machinery to nucleoli independently of promoter elements.
The Rice COLEOPTILE PHOTOTROPISM1 Gene Encoding an Ortholog of Arabidopsis NPH3 Is Required for Phototropism of Coleoptiles and Lateral Translocation of Auxin
Authors: Haga Ken , Takano Makoto , Neumann Ralf , Iino Moritoshi
Published: December 2004

We isolated a mutant, named coleoptile phototropism1 (cpt1), from γ-ray–mutagenized japonica-type rice (Oryza sativa). This mutant showed no coleoptile phototropism and severely reduced root phototropism after continuous stimulation. A map-based cloning strategy and transgenic complementation test were applied to demonstrate that a NPH3-like gene deleted in the mutant corresponds to CPT1. Phylogenetic analysis of putative CPT1 homologs of rice and related proteins indicated that CPT1 has an orthologous relationship with Arabidopsis thaliana NPH3. These results, along with those for Arabidopsis, demonstrate that NPH3/CPT1 is a key signal transduction component of higher plant phototropism. In an extended study with the cpt1 mutant, it was found that phototropic differential growth is accompanied by a CPT1-independent inhibition of net growth. Kinetic investigation further indicated that a small phototropism occurs in cpt1 coleoptiles. This response, induced only transiently, was thought to be caused by the CPT1-independent growth inhibition. The 3H-indole-3-acetic acid applied to the coleoptile tip was asymmetrically distributed between the two sides of phototropically responding coleoptiles. However, no asymmetry was induced in cpt1 coleoptiles, indicating that lateral translocation of auxin occurs downstream of CPT1. It is concluded that the CPT1-dependent major phototropism of coleoptiles is achieved by lateral auxin translocation and subsequent growth redistribution.
The characteristic histopathologic features of nevi on and around the ear
Authors: Lazova Rossitza , Lester Brian , Glusac Earl J. , Handerson Tamara , McNiff Jennifer
Published: December 2004

Background:  Nevi on certain areas of the body such as the acral, genital, and flexural regions may exhibit uncommon but characteristic histopathologic features. The purpose of this study was to characterize the distinctive features of nevi with a junctional component located on and around the ear.

Materials and methods:  A total of 101 compound and junctional nevi of the ear received at the Yale Dermatopathology Laboratory during a 10‐year period were examined in this study. The most characteristic feature of the majority of these nevi was irregularity of nesting pattern, with nests, which varied in size and shape and which were sometimes located between rete ridges.

Results:  Forty‐two (42%) of nevi on and around the ear showed poor circumscription, lateral extension of the junctional component beyond the dermal component, and elongation of rete ridges with bridging between them. A subset of these nevi (26 cases) showed uniformly large melanocytes with large vesicular nuclei without prominent nucleoli, and abundant pale, finely granular cytoplasm. These lesions did not show a tendency to recur.

Conclusions:  This study supports the existence of a subset of nevi on or near the ear that, like certain nevi located on other special sites, exhibit unusual but characteristic features, which may be misinterpreted as atypical or malignant.
CD4+CD25+ regulatory T cells: I. Phenotype and physiology
Authors: HOLM THOMAS LINDEBO , NIELSEN JANNE , CLAESSON MOGENS H.
Published: December 2004

The immune system protects us against foreign pathogens. However, if fine discrimination between self and non‐self is not carried out properly, immunological attacks against self may be launched leading to autoimmune diseases, estimated to afflict up to 5% of the population. During the last decade it has become increasingly clear that regulatory CD4+CD25+ T cells (Treg cells) play an important role in the maintenance of immunological self‐tolerance, and that this cell subset exerts its function by suppressing the proliferation or function of autoreactive T cells. Based on human and murine observations, this review presents a characterization of the phenotype and functions of the Treg cells in vitro and in vivo. An overview of the surface molecules associated with and the cytokines produced by the Treg cells is given and the origin, activation requirements and mode of action of the Treg cells are discussed. Finally, we address the possibility that Treg cells may play a central role in immune homeostasis, regulating not only autoimmune responses, but also immune responses toward foreign antigens.
CD4+CD25+ regulatory T cells: II. Origin, disease models and clinical aspects
Authors: NIELSEN JANNE , HOLM THOMAS LINDEBO , CLAESSON MOGENS H.
Published: December 2004

Autoimmune diseases afflict approximately 5% of the population and reflect a failure in the immune system to discriminate between self and non‐self resulting in the breakdown of self‐tolerance. Regulatory CD4+CD25+ T cells (Treg cells) have been shown to play an important role in the maintenance of immune homeostasis and self‐tolerance by counteracting the development and effector functions of potentially autoreactive T cells. We have in the previous APMIS review described the phenotype and physiology of Treg cells. The present overview deals with the thymic origin of Treg cells and their role in disease models such as autoimmune gastritis and inflammatory bowel disease. Finally, we will consider some aspects of the therapeutic potential of Treg cells.
Generalized least-squares fit of multiequation models
Authors: Marshall Simon L. , Blencoe James G.
Published: December 2004

A method for fitting multiequation models to data sets of finite precision is proposed. This is based on the Gauss–Newton algorithm devised by Britt and Luecke (1973); the inclusion of several equations of condition to be satisfied at each data point results in a block diagonal form for the effective weighting matrix. This method allows generalized nonlinear least-squares fitting of functions that are more easily represented in the parametric form (x(t),y(t)) than as an explicit functional relationship of the form y=f(x). The Aitken (1935) formulas appropriate to multiequation weighted nonlinear least squares are recovered in the limiting case where the variances and covariances of the independent variables are zero. Practical considerations relevant to the performance of such calculations, such as the evaluation of the required partial derivatives and matrix products, are discussed in detail, and the operation of the algorithm is illustrated by applying it to the fit of complex permittivity data to the Debye equation.
Fraunhofer diffraction by a thin wire and Babinet’s principle
Authors: Ganci Salvatore
Published: December 2004

The Fraunhofer diffraction of a Gaussian wave field incident on a thin wire is examined. It is shown theoretically and experimentally that a simple application of Babinet’s principle leads to erroneous results.
A classical experiment revisited: The bounce of balls and superballs in three dimensions
Authors: Doménech Antonio
Published: December 2004

A description of the inelastic collision of a ball when it bounces on a rigid horizontal surface with arbitrary initial spin conditions is presented. I consider cases where rebound occurs with and without sliding, and when the ball grips the surface. Two rebound models are discussed in which friction is described in terms of the static and dynamic coefficients of friction and the friction is expressed in terms of horizontal coefficients of restitution. The azimuthal and vertical deviation angles of the ball after impact are predicted as a function of the incident angle. We present data from an experiment in which a ball is launched horizontally from the edge of the laboratory bench and then rebounds on a horizontal surface. Ordinary balls exhibit two rebound regimes, with and without sliding, and can be satisfactorily described by the first model. Superballs exhibit a grip behavior whose description requires the use of the second model.
Dual Transcriptional Control of
amfTSBA
, Which Regulates the Onset of Cellular Differentiation in
Streptomyces griseus
Authors: Ueda Kenji , Takano Hideaki , Nishimoto Madoka , Inaba Hiromi , Beppu Teruhiko
Published: December 2004

The
amf
gene cluster encodes a probable secretion system for a peptidic morphogen, AmfS, which induces aerial mycelium formation in
Streptomyces griseus
. Here we examined the transcriptional control mechanism for the promoter preceding
amfT
(P
amfT
) directing the transcription of the
amfTSBA
operon. High-resolution S1 analysis mapped a transcriptional start point at 31 nucleotides upstream of the translational start codon of
amfT
. Low-resolution analysis showed that P
amfT
is developmentally regulated in the wild type and completely abolished in an
amfR
mutant. The −35 region of P
amfT
contained the consensus sequence for the binding of BldD, a pleiotropic negative regulator for morphological and physiological development in
Streptomyces coelicolor
A3(2). The cloned
bldD
locus of
S. griseus
showed high sequence similarity to the
S. coelicolor
counterpart. Transcription of
bldD
occurred constitutively in both the wild type and an A-factor-deficient mutant of
S. griseus
, which suggests that the regulatory role of BldD is independent of A-factor. The gel retardation assay revealed that purified BldD and AmfR recombinant proteins specifically bind P
amfT
. Overproduction of BldD in the wild-type cell conferred a bald phenotype (defective in aerial growth and streptomycin production) and caused marked repression of P
amfT
activity. An
amfT
-depleted mutant also showed a bald phenotype but P
amfT
activity was not affected. Both the
bldD
-overproducing wild-type strain and the
amfT
mutant were unable to induce aerial growth of an
amfS
mutant in a cross-feeding assay, which indicates that these strains are defective in the production of an active AmfS peptide. The results overall suggests that two independent regulators, AmfR and BldD, control P
amfT
activity via direct binding to determine the transcriptional level of the
amf
operon responsible for the production and secretion of AmfS peptide, which induces the erection of aerial hyphae in
S. griseus
.
Genetic Analysis of the HAMP Domain of the Aer Aerotaxis Sensor Localizes Flavin Adenine Dinucleotide-Binding Determinants to the AS-2 Helix
Authors: Ma Qinhong , Johnson Mark S. , Taylor Barry L.
Published: December 2004

HAMP domains are signal transduction domains typically located between the membrane anchor and cytoplasmic signaling domain of the proteins in which they occur. The prototypical structure consists of two helical amphipathic sequences (AS-1 and AS-2) connected by a region of undetermined structure. TheEscherichia coliaerotaxis receptor, Aer, has a HAMP domain and a PAS domain with a flavin adenine dinucleotide (FAD) cofactor that senses the intracellular energy level. Previous studies reported mutations in the HAMP domain that abolished FAD binding to the PAS domain. In this study, using random and site-directed mutagenesis, we identified the distal helix, AS-2, as the component of the HAMP domain that stabilizes FAD binding. AS-2 in Aer is not amphipathic and is predicted to be buried. Mutations in the sequence coding for the contiguous proximal signaling domain altered signaling by Aer but did not affect FAD binding. The V264M residue replacement in this region resulted in an inverted response in whichE. colicells expressing the mutant Aer protein were repelled by oxygen. Bioinformatics analysis of aligned HAMP domains indicated that the proximal signaling domain is conserved in other HAMP domains that are not involved in chemotaxis or aerotaxis. Only one null mutation was found in the coding sequence for the HAMP AS-1 and connector regions, suggesting that these are not active signal transduction sites. We consider a model in which the signal from FAD is transmitted across a PAS-HAMP interface to AS-2 or the proximal signaling domain.
Posttranscriptional Repression of GacS/GacA-Controlled Genes by the RNA-Binding Protein RsmE Acting Together with RsmA in the Biocontrol StrainPseudomonas fluorescensCHA0
Authors: Reimmann Cornelia , Valverde Claudio , Kay Elisabeth , Haas Dieter
Published: December 2004

In the plant-beneficial soil bacteriumPseudomonas fluorescensCHA0, the production of biocontrol factors (antifungal secondary metabolites and exoenzymes) is controlled at a posttranscriptional level by the GacS/GacA signal transduction pathway involving RNA-binding protein RsmA as a key regulatory element. This protein is assumed to bind to the ribosome-binding site of target mRNAs and to block their translation. RsmA-mediated repression is relieved at the end of exponential growth by two GacS/GacA-controlled regulatory RNAs RsmY and RsmZ, which bind and sequester the RsmA protein. A gene (rsmE) encoding a 64-amino-acid RsmA homolog was identified and characterized in strain CHA0. Overexpression ofrsmEstrongly reduced the expression of target genes (hcnA,for a hydrogen cyanide synthase subunit;aprA, for the main exoprotease; andphlA, for a component of 2,4-diacetylphloroglucinol biosynthesis). Single null mutations in eitherrsmAorrsmEresulted in a slight increase in the expression ofhcnA,aprA, andphlA. By contrast, anrsmA rsmEdouble mutation led to strongly increased and advanced expression of these target genes and completely suppressed agacSmutation. Both the RsmE and RsmA levels increased with increasing cell population densities in strain CHA0; however, the amount of RsmA showed less variability during growth. Expression ofrsmEwas controlled positively by GacA and negatively by RsmA and RsmE. Mobility shift assays demonstrated specific binding of RsmE to RsmY and RsmZ RNAs. The transcription and stability of both regulatory RNAs were strongly reduced in thersmA rsmEdouble mutant. In conclusion, RsmA and RsmE together account for maximal repression in the GacS/GacA cascade of strain CHA0.
Identification of a
Dichelobacter nodosus
Ferric Uptake Regulator and Determination of Its Regulatory Targets
Authors: Parker Dane , Kennan Ruth M. , Myers Garry S. , Paulsen Ian T. , Rood Julian I.
Published: December 2004

The expression of iron regulated genes in bacteria is typically controlled by the ferric uptake regulator (Fur) protein, a global transcriptional repressor that regulates functions as diverse as iron acquisition, oxidative stress, and virulence. We have identified a
fur
homologue in
Dichelobacter nodosus
, the causative agent of ovine footrot, and shown that it complements an
Escherichia coli fur
mutant. Homology modeling of the
D. nodosus
Fur protein with the recently solved crystal structure of Fur from
Pseudomonas aeruginosa
indicated extensive structural conservation. As Southern hybridization analysis of different clinical isolates of
D. nodosus
indicated that the
fur
gene was present in all of these strains, the
fur
gene was insertionally inactivated to determine its functional role. Analysis of these mutants by various techniques did not indicate any significant differences in the expression of known virulence genes or in iron-dependent growth. However, we determined several Fur regulatory targets by two-dimensional gel electrophoresis coupled with mass spectrometry. Analysis of proteins from cytoplasmic, membrane, and extracellular fractions revealed numerous differentially expressed proteins. The transcriptional basis of these differences was analyzed by using quantitative reverse transcriptase PCR. Proteins with increased expression in the
fur
mutant were homologues of the periplasmic iron binding protein YfeA and a cobalt chelatase, CbiK. Down-regulated proteins included a putative manganese superoxide dismutase and ornithine decarboxylase. Based on these data, it is suggested that in
D. nodosus
the Fur protein functions as a regulator of iron and oxidative metabolism.
Proteomics Analysis by Two-Dimensional Differential Gel Electrophoresis Reveals the Lack of a Broad Response of
Neisseria meningitidis
to In Vitro-Produced AI-2
Authors: Schauder Stephan , Penna Lucia , Ritton Adeline , Manin Catherine , Parker Fabienne , Renauld-Mongénie Geneviève
Published: December 2004

To investigate the effect of the autoinducer AI-2 on protein expression in
Neisseria meningitidis
, a
luxS
mutant of strain MC58 was grown in the presence and absence of in vitro-produced AI-2, and differential protein expression was assessed by two-dimensional differential gel electrophoresis.
N. meningitidis
did not show a global response to AI-2 signaling activity.
Light Signaling in Scotopic Conditions in the Rabbit, Mouse and Rat Retina: A Physiological and Anatomical Study
Authors: Protti Dario A. , Flores-Herr Nicolas , Li Wei , Massey Stephen C. , Wässle Heinz
Published: December 2004

In the dark, light signals are conventionally routed through the following circuit: rods synapse onto rod bipolar (RB) cells, which in turn contact AII amacrine cells. AII cells segregate the light signal into the on and off pathways by making electrical synapses with on cone bipolar (CB) cells and glycinergic inhibitory chemical synapses with off CB cells. These bipolar cells synapse onto their respective ganglion cells, which transfer on and off signals to the visual centers of the brain. Two alternative pathways have recently been postulated for the signal transfer in scotopic conditions: 1) electrical coupling between rods and cones, and 2) a circuit independent of cone photoreceptors, implying direct contacts between rods and off CB cells. Anatomical evidence supports the existence of both these circuits. To investigate the contribution of these alternative pathways to scotopic vision in the mammalian retina, we have performed patch-clamp recordings from ganglion cells in the dark-adapted retina of the rabbit, mouse, and rat. Approximately one-half of the ganglion cells in the rabbit retina received off signals through a circuit that was independent of RB cells. This was shown by their persistence in the presence of the glutamate agonist 2-amino-4-phosphonobutyric acid (APB), which blocks rod→RB cell signaling. Consistent with this result, strychnine, a glycine receptor antagonist, was unable to abolish these off responses. In addition, we were able to show that some off cone bipolar dendrites terminate at rod spherules and make potential contacts. In the mouse retina, however, there seems to be a very low proportion of off signals carried by an APB-resistant pathway. No ganglion cells in the rat retina displayed APB- and strychnine-resistant responses. Our data support signaling through flat contacts between rods and off CB cells as the alternative route, but suggest that the significance of this pathway differs between species.
Microarray gene expression analysis of theFob3bobesity QTL identifies positional candidate geneSqleand perturbed cholesterol and glycolysis pathways
Authors: Stylianou Ioannis M. , Clinton Michael , Keightley Peter D. , Pritchard Clare , Tymowska-Lalanne Zuzzana , Bünger Lutz , Horvat Simon
Published: December 2004

Obesity-related diseases are poised to become the primary cause of death in developed nations. While a number of monogenic causes of obesity have recently been identified, these are responsible for only a small proportion of human cases of obesity. Quantitative trait locus (QTL) studies using animal models have revealed hundreds of potential loci that affect obesity; however, few have been further analyzed beyond the original QTL scan. We previously mapped four QTL in an F2between divergently selected Fat (F) and Lean (L) lines. A QTL of large effect on chromosome 15 ( Fob3) was subsequently mapped to a higher resolution into two smaller-effect QTL ( Fob3a and Fob3b) using crosses between the F-line and a congenic line containing L-line alleles at the Fob3 QTL region. Here we report the gene expression characterization of Fob3b. Microarray expression analysis using the NIA-NIH 15K cDNA array set containing 14,938 mouse ESTs was employed to identify candidate genes and pathways that are differentially expressed between the F-line and a congenic line containing only the Fob3b QTL ( Fob3b-line). Our study suggests squalene epoxidase (Sqle), a cholesterol biosynthesis enzyme, as a strong positional candidate gene for Fob3b. Several other cholesterol biosynthesis pathway genes unlinked to Fob3b were found to be differentially expressed, suggesting that a perturbation of this pathway could be in part responsible for the phenotypic difference between the F-line and Fob3b-line mice.
Environmental Ethics from An Interdisciplinary Perspective: The Marquette Experience
Authors: Schaefer Jame
Published: December 2004

Marquette University's new Interdisciplinary Minor in Environmental Ethics moves beyond a multidisciplinary approach to learning by integrating and applying the knowledge and skills acquired in ecology, natural resource economics, environmental philosophy, earth physics, and theology courses. The first two years of this interdisciplinary program provided an opportunity for faculty and students to experiment with collaborative methods in their individual courses, and culminated in a capstone seminar that focused on the ethical implications of electricity generation and use in the United States. From this experience, a more comprehensive approach to addressing environmental problems from an ethical perspective was developed, and more effective ways of teaching and learning were identified to improve the program.
Environmental Education And Metaethics
Authors: Goldin Owen
Published: December 2004

Contrā Dale Jamieson, the study of the metaethical foundations of environmental ethics may well lead students to a more environmentally responsible way of life. For although metaethics is rarely decisive in decision making and action, there are two kinds of circumstances in which it can play a crucial role in our practical decisions. First, decisions that have unusual features do not summon habitual ethical reactions, and hence invite the application of ethical precepts that the study of metaethics and ethical theory isolate and clarify. Second, there are times in which the good of others (including organisms and systems in the natural world) may well be given greater weight in one's ethical deliberations if theory has made clear that the good to be promoted is ontologically independent of one's own good.
Control as an Engagement Feature for Young Children’s Attention to and Learning of Computer Content
Authors: Calvert Sandra L. , Strong Bonnie L. , Gallagher Lizann
Published: December 2004

This article examines a study in which young children were exposed to a computer story that varied the amount of control that children had over the visual and verbal content. Children who controlled the computer demonstrated more attention and involvement than those who watched an adult control the experience. Boys who had an adult control the program were more likely to try to gain control of the activity by making attempts to get the mouse or by asking to change activities. Control, however, had no effect on children’s memory of visual or verbal content. The implication is that control is an engagement feature that has its greatest impact when examining attention and interest, a lesson that may facilitate constructive early adult-child interactions with educational computer software.
Democratization and Constitutional Crises in Presidential Regimes
Authors: Pérez-Liñán Aníbal
Published: December 2004

This article explores the impact of democratization on the resolution of executive-legislative crises in Latin American presidential regimes. The author studies 27 episodes in which the executive branch closed the legislature or the legislature removed the chief executive from office between 1950 and 2000. It is hypothesized that the democratization of Latin American presidential systems has hindered the ability of presidents to challenge the legislature and encouraged the emergence of congressional supremacy (i.e., the capacity of congress to impeach the president if a serious conflict emerges). Three causal mechanisms account for this outcome: (a) a lower likelihood of military intervention, (b) the elimination of constitutional tools used by authoritarian presidents to dissolve congress, and (c) greater stability in the constitutional environment. After discussing the limitations of conventional maximum likelihood tests, the author assesses this hypothesis using a fuzzy-set qualitative comparative model.
Demographic and Social Variables Associated with Psychiatric and School-Related Indicators for Asian/Pacific-Islander Adolescents
Authors: Hishinuma Earl S. , Johnson Ronald C. , Carlton Barry S. , Andrade Naleen N. , Nishimura Stephanie T. , Goebert Deborah A. , Yuen Noelle Y.C. , Wegner Eldon L. , Makini George K. , Nahulu Linda B. , Else Iwalani R.N. , Chang Janice Y.
Published: December 2004

Background: Factors associated with Asian/Pacific-Islander adolescent adjustment is a greatly neglected research area.

Aims: The purpose of the present study was to investigate the relation between demographic, social and adjustment measures based on a large-scale investigation of Asian/Pacific-Islander youths.

Method: A total of 2577 adolescents were surveyed across 4 public schools in Hawai‘i during the 1992-1993 school year.

Results: Three social variables (number of relatives frequently seen, family support and friends’ support) exhibited statistically significant but low correlations. Family support had the highest negative association with the four psychiatric symptoms (depression, anxiety, aggression, substance use). Friends’ support was inconsistently associated with the adjustment measures, and the number of relatives frequently seen resulted in negligible effects. In contrast, demographic variables, especially ethnicity, played a much greater role in the association with the four school-related measures (grade-point average, absences, suspensions, conduct infractions).

Discussion: For Asian/Pacific-Islander youths, the quality of the social supports, including family relations, may be particularly important in the adolescents’ adjustment. When examining school-related outcomes, demographic variables, with particular emphases on ethnicity and culture, must be considered. When developing and implementing prevention and intervention services and programs, consideration of family and ethnic-cultural influences should be taken into account, with further research needed in several related domains: other SES influences, life stressors, migration-generational effects, ethnic identity, self-concept indicators and socio-political aspects.
Impact of Gender And Parents’ Marital Status on Adolescents’ Suicidal Ideation
Authors: Ang Rebecca P. , Ooi Yoon Phaik
Published: December 2004

This study investigated the effect of gender and parents’ marital status on adolescents’ suicidal ideation in a sample of Grade 8 and Grade 9 students (mean age 14.12 years) in Singapore. Two hundred and seventy-one (149 boys and 122 girls) students completed the junior high school version of the Suicidal Ideation Questionnaire (SIQ-JR) and a short demographic questionnaire. Consistent with our hypothesis, the 2 (Gender) 2 (Parents’ marital status) ANOVA yielded a statistically significant interaction effect as expected. Specifically, tests of simple effects reveal that adolescent boys from single-parent families were found to be significantly higher on suicidal ideation compared with adolescent boys from two-parent families. This difference was not found among adolescent girls - adolescent girls from single-parent and two-parent families did not differ significantly on suicidal ideation. Being a boy in a single-parent home environment may increase one’s risk for endorsing clinically significant suicidal ideation.
Attitude Toward and Knowledge about Mental Illness in Fiji Islands
Authors: Aghanwa Henry Stephens
Published: December 2004

Backgrounds: There is a dearth of information on the extent of knowledge about mental illness and attitudes toward the mentally ill in Fiji.

Aims: This study aimed to explore these aspects, and also to determine the factors influencing them.

Method: Market vendors, peri-urban dwellers, white-collar and health workers from Greater Suva were interviewed. The interview schedule used elicited socio-demographic characteristics, knowledge of, and attitudes toward, mental illness.

Results: A majority of the subjects attributed the cause of mental illness to substance abuse, believed in the diversity of mental illness, considered hospital as an important source of help and acknowledged the effectiveness of medication.

Less than one-fifth of the subjects were willing to marry or employ mentally ill persons. About 42% of the sample would be deterred by embarrassment from seeking help.

Educational attainment was correlated with knowledge about mental illness, except with knowledge about early mental symptoms ( p < 0.01). Prestigious occupation, single marital status, female gender, younger age and urban dwelling were associated with positive disposition toward the mentally ill ( p < 0.01). Race was not significantly influential on almost all attitudinal variables.

Conclusion: Health education is capable of positively influencing knowledge about, and attitudes toward, mental illness in Fiji.
Compression Characterization of High-modulus Carbon Fibers
Authors: Montagnier O. , Hochard C.
Published: December 2004

The study deals with testing and modeling the mesoscopic compression behavior of high-modulus carbon fibers-reinforced epoxy. These fibers are very stiff, but their compression performances are poor. To decrease the risk margins during the sizing process, it is necessary to determine their compression behavior as accurately as possible. Two tests were carried out on two types of high-modulus carbon fibers (M55J fibers and K63712 fibers): the pure compression Celanese test, which gives poor strain results, and a new pure bending test, which allows large displacements and generates higher strain levels. This bending test makes it possible to know without inverse calculation the load for any sections and to use machine specimens in order to avoid tab effects. An elastic nonlinear model (a power function of the strain) is proposed to describe the loss of compressive rigidity until the brittle rupture. Model coefficients are identified for the two materials with a simple inverse calculation. The pure bending test brought to light a highly nonlinear behavior of the unidirectional K63712 fibers.
Structure–Properties Relationship of Short Jute Fiber-reinforced Polypropylene Composites
Authors: Cabral H. , Cisneros M. , Kenny J. M. , Vazquez A. , Bernal C. R.
Published: December 2004

In the present work, mechanical response, water uptake, and dielectric properties of jute fiber-reinforced polypropylene (PP) composites are studied. Uniaxial tensile and Izod notched tests are conducted for a range of fiber volume fraction. It was found that the tensile Young’s modulus and tensile strength monotonically increased with increasing the fiber volume fraction, whereas the impact resistance increased up to a critical value of the fiber volume fraction and then declined. Furthermore, different predictive models are successfully applied to describe the dependence of tensile properties on fiber content. Fracture surface observation by SEM of samples broken in static and impact tests showed matrix yielding and brittle matrix behavior, respectively. Fiber pullout and poor fiber– matrix adhesion were also observed in the fracture surfaces. A change in the dependence of the water uptake and dielectric properties with fiber loading at a critical fiber content was also found.
Pharmacokinetics of Aripiprazole and Concomitant Lithium and Valproate
Authors: Citrome Leslie , Josiassen Richard , Bark Nigel , Salazar Daniel E. , Mallikaarjun Suresh
Published: December 2004

The objective of this study was to assess the pharmacokinetics of the antipsychotic aripiprazole when coadministered with lithium or valproate. Two open‐label, sequential treatment design studies were conducted in chronically institutionalized patients with schizophrenia or schizoaffective disorder requiring treatment with lithium (n = 12) or valproate (divalproex sodium) (n=10). Patients received aripiprazole 30 mg/day on days 1 to 14 and aripiprazole with concomitant therapy on days 15 to 36. Lithium was titrated from 900 mg until serum concentrations reached 1.0 to 1.4 mEq/L for at least 5 days. Valproate was titrated to 50 to 125 mg/L. Coadministration with lithium increased mean Cmax and AUC values of aripiprazole by about 19% and 15%, respectively, whereas the apparent oral clearance decreased by 15%. There was no effect on the steady‐state pharmacokinetics of the active metabolite of aripiprazole. Coadministration with valproate decreased the AUC and Cmax of aripiprazole by 24% and 26%, respectively, with minimal effects on the active metabolite. Therapeutic doses of lithium and divalproex had no clinically significant effects on the pharmacokinetics of aripiprazole in patients with schizophrenia or schizoaffective disorder.
Comparison of the Pharmacokinetics of Hawthorn Phenolics in Extract Versus Individual Pure Compound
Authors: Chang Qi , Zuo Zhong , Ho Walter K. K. , Chow Moses S. S.
Published: December 2004

The pharmacokinetics of an active herbal substance may be different when administered in an extract form as compared to that when administered as a pure compound. This study investigated the pharmacokinetics of 4 active compounds of hawthorn fruits—namely, (−)‐epicatechin, chlorogenic acid, hyperoside, and isoquercitrin—following administration of an extract formulation (as hawthorn phenolic extract, which contained the active compounds) or equivalent doses of individual pure compound in male Sprague‐Dawley rats (n = 5 per group). The hawthron phenolic extract or pure compounds were administered both orally and intravenously. Following administration, multiple plasma samples were obtained, and the plasma concentrations were determined by high‐performance liquid chromatography. After the intravenous injection of hawthorn phenolic extract, higher plasma drug concentration, larger area under the plasma concentration‐time curve from 0 to infinity, longer terminal elimination half‐life, smaller apparent volume of distribution, lower total body clearance, and higher urinary excretion of each compound were obtained when compared to that after the pure compound. Following the oral administration of either hawthorn phenolic extract or pure compound, only epicatechin was absorbed, and their pharmacokinetics were generally not significantly different between these 2 formulations. The differences in the pharmacokinetics of the 2 formulations following intravenous but not oral administration may be attributable to the existence of other co‐occurring components in the hawthorn phonolic extract (which may be present in the body after intravenous but not oral administration). The results showed that an herbal extract formulation, when administered intravenously, could potentially alter the pharmacokinetics of its active ingredients.
Knowledge or Trust?
Authors: Moy Patricia , Torres Marcos , Tanaka Keiko , McCluskey Michael R.
Published: December 2004

Participation as a key component of democracy has been the focus of considerable research, with the body of scholarship focusing overwhelmingly on voting. However, because political interests and opinions can be conveyed and expressed outside the voting booth, this study examines political activity in a nonelectoral context, specifically, World Trade Organization (WTO) policies and issues as well as the WTO ministerial meeting held in Seattle, Washington, in the fall of 1999. Within this context, this study explores the process of media effects on participation, focusing on knowledge and trust in the organization as intervening variables between attention to WTO news and anticipated behaviors related to the WTO. Survey data collected from 277 adults from the greater Seattle area prior to the WTO meeting were used to test seven hypotheses and address two research questions. Results indicate that newspaper and television reliance had differential effects on knowledge about the WTO and trust in the institution. Moreover, the effects of trust on political behavior were considerably stronger than those of knowledge.
Violent Men
Authors: Seager James A.
Published: December 2004

Fifty federally incarcerated males completed a self-report measure of impulsivity called the I Questionnaire. Offender self-schemas for a hostile world were measured with responses to questions about hypothetical social situations and with perceptions of weapons during a binocular rivalry task. Multiple regression analysis indicated that 31% of the variance in violent criminal history and 48% of the variance in psychopathy, as measured with the Psychopathy Checklist–Revised, could be accounted for by combinations of impulsivity and self-schemas for a hostile world. It was concluded that persistently violent males and males with traits of psychopathy impulsively react to attributions that others are threatening them.
Historical and Personality Correlates to the Violence Patterns of Juveniles Tried as Adults
Authors: Kruh Ivan P. , Frick Paul J. , Clements Carl B.
Published: December 2004

This study examined the utility of several personality indices for explaining variance in the frequency, variety, and situational correlates of past violence exhibited by imprisoned juveniles after controlling for historical risk factors. One hundred prison inmates ages 16 to 21 who were juveniles at the time of their adjudication completed personality measures assessing overcontrolled hostility and psychopathic traits, and they reported on the number and types of past violence and the situational correlates (e.g., location of violent episodes, victim characteristics, and precipitating events) to their violent behavior. The measure of overcontrolled hostility and the historical risk assessment indices were not significantly associated with the frequency or variety of past violent behavior nor were they significantly associated with the situational correlates to violence. In contrast, a measure of psychopathic traits demonstrated significant incremental validity after controlling for historical data in its association with the frequency, variety, and situational patterns of violent behavior.
Diversity of accuracy profiles for absolute pitch recognition
Authors: Bahr Nan , Christensen Carol A. , Bahr Mark
Published: December 2004

Most advanced musicians are able to identify and label a heard pitch if given an opportunity to compare it to a known reference note. This is called ‘relative pitch’ (RP). A much rarer skill is the ability to identify and label a heard pitch without the need for a reference. This is colloquially referred to as ‘perfect pitch’, but appears in the academic literature as ‘absolute pitch’ (AP). AP is considered by many as a remarkable skill. As people do not seem able to develop it intentionally, it is generally regarded as innate. It is often seen as a unitary skill and that a set of identifiable criteria can distinguish those who possess the skill from those who do not. However, few studies have interrogated these notions. The present study developed and applied an interactive computer program to map pitch-labelling responses to various tonal stimuli without a known reference tone available to participants. This approach enabled the identification of the elements of sound that impacted on AP. Pitch-labelling responses of 14 participants with AP were recorded for their accuracy. Each participant’s response to the stimuli was unique. Their accuracy of labelling varied across dimensions such as timbre, range and tonality. The diversity of performance between individuals appeared to reflect their personal musical experience histories.