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Terms modified by Adding Selected AbstractsScalable real-time animation of riversCOMPUTER GRAPHICS FORUM, Issue 2 2009Qizhi Yu Many recent games and applications target the interactive exploration of realistic large scale worlds. These worlds consist mostly of static terrain models, as the simulation of animated fluids in these virtual worlds is computationally expensive. Adding flowing fluids, such as rivers, to these virtual worlds would greatly enhance their realism, but causes specific issues: as the user is usually observing the world at close range, small scale details such as waves and ripples are important. However, the large scale of the world makes classical methods impractical for simulating these effects. In this paper, we present an algorithm for the interactive simulation of realistic flowing fluids in large virtual worlds. Our method relies on two key contributions: the local computation of the velocity field of a steady flow given boundary conditions, and the advection of small scale details on a fluid, following the velocity field, and uniformly sampled in screen space. [source] Service Personnel, Technology, and Their Interaction in Influencing Customer Satisfaction,DECISION SCIENCES, Issue 1 2006Craig M. Froehle ABSTRACT Managing both the technologies and the personnel needed for providing high-quality, multichannel customer support creates a complex and persistent operational challenge. Adding to this difficulty, it is still unclear how service personnel and these new communication technologies interact to influence the customer's perceptions of the service being provided. Motivated by both practical importance and inconsistent findings in the academic literature, this exploratory research examines the interaction of media richness, represented by three different technology contexts (telephone, e-mail, and online chat), with six customer service representative (CSR) characteristics and their influences on customer satisfaction. Using a large-sample customer survey data set, the article develops a multigroup structural equation model to analyze these interactions. Results suggest that CSR characteristics influence customer service satisfaction similarly across all three technology-mediated contexts. Of the characteristics studied, service representatives contribute to customer satisfaction more when they exhibit the characteristics of thoroughness, knowledgeableness, and preparedness, regardless of the richness of the medium used. Surprisingly, while three other CSR characteristics studied (courtesy, professionalism, and attentiveness) are traditionally believed to be important in face-to-face encounters, they had no significant impact on customer satisfaction in the technology-mediated contexts studied. Implications for both practitioners and researchers are drawn from the results and future research opportunities are discussed. [source] Temperature perception and nociceptionDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2004Barry G. Green Abstract The specificity theory of somesthesis holds that perceptions of warmth, cold, and pain are served by separate senses. Although no longer accepted in all its details, the theory's basic assumptions of anatomical and functional specificity have remained guiding principles in research on temperature perception and its relationship to pain. This article reviews the response characteristics of thermoreceptors, temperature-sensitive nociceptors, and their associated pathways in the context of old and new perceptual phenomena, most of which cannot be satisfactorily explained by the specificity theory. The evidence indicates that throughout most of the perceptual range, temperature sensitivity depends upon coactivation of, and interactions among, thermal and nociceptive pathways that are composed of both specific "labeled lines" and nonspecific, multimodal fibers. Adding to this complexity is evidence that tactile stimulation can influence the way in which thermal stimulation is perceived. It is argued that thermoreception is best defined as a functional subsystem of somesthesis that serves the very different and sometimes conflicting demands of thermoregulation, protection from thermal injury, and haptic perception. © 2004 Wiley Periodicals, Inc. J Neurobiol 61: 13,29, 2004 [source] Dopamine receptors modulate ethanol's locomotor-activating effects in preweanling ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2010Carlos Arias Abstract Near the end of the second postnatal week motor activity is increased soon after ethanol administration (2.5,g/kg) while sedation-like effects prevail when blood ethanol levels reach peak values. This time course coincides with biphasic reinforcement (appetitive and aversive) effects of ethanol determined at the same age. The present experiments tested the hypothesis that ethanol-induced activity during early development in the rat depends on the dopamine system, which is functional in modulating motor activity early in ontogeny. Experiments 1a and 1b tested ethanol-induced activity (0 or 2.5,g/kg) after a D1-like (SCH23390; 0, .015, .030, or .060,mg/kg) or a D2-like (sulpiride; 0, 5, 10, or 20,mg/kg) receptor antagonist, respectively. Ethanol-induced stimulation was suppressed by SCH23390 or sulpiride. The dopaminergic antagonists had no effect on blood ethanol concentration (Experiments 2a and 2b). In Experiment 3, 2.5,g/kg ethanol increased dopamine concentration in striatal tissue as well as locomotor activity in infant Wistar rats. Adding to our previous results showing a reduction in ethanol induced activity by a GABA B agonist or a nonspecific opioid antagonist, the present experiments implicate both D1-like and D2-like dopamine receptors in ethanol-induced locomotor stimulation during early development. According to these results, the same mechanisms that modulate ethanol-mediated locomotor stimulation in adult rodents seem to regulate this particular ethanol effect in the infant rat. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 52: 13,23, 2010 [source] Religious Persecution: And What To Do About ItDIALOG, Issue 2 2002John Hilary Martin Hinduism, Islam, Christianity, Buddhism, and other religions can all be found in geographically diverse Indonesia. Adding to this layered society are many different ethnic groups, political groups, and socio,economic groups. The joining of all these factors led to different communities forming adats,religio,customary agreements. When talking about "religious persecution" in Indonesia, all of these factors must be taken into account. Even so, it would be extremely naive to think that religious belief is a peripheral motivation for violence. This article explores a method by which religious scholars, leaders, and communities can curtail religious persecution in Indonesia; the method includes: personal encounter; discussion of the scholarly agenda; a public engagement through dialogue that leads to commitment; and finally, the appeal of prayer and ritual. [source] A randomized controlled trial of adding the nicotine patch to rimonabant for smoking cessation: efficacy, safety and weight gainADDICTION, Issue 2 2009Nancy A. Rigotti ABSTRACT Aims Because smoking cessation rates might be improved by combining drugs and by reducing post-cessation weight gain, we tested the smoking cessation efficacy, safety and effect on body weight of adding the nicotine patch to rimonabant, a cannabanoid type-1 receptor antagonist that reduces body weight. Design Randomized double-blind placebo-controlled trial. Setting Fifteen US research centers. Participants A total of 755 smokers (,15 cigarettes/day). Intervention Rimonabant (20 mg daily) was given open-label for 9 weeks. The 735 participants completing week 1 were randomized at day 8 (target quit day) to add a nicotine patch (n = 369) or placebo patch (n = 366) for 10 weeks (21 mg daily for 8 weeks plus a 2-week taper). Participants received weekly smoking counseling and were followed for 24 weeks. Measurements Biochemically validated 4-week continuous abstinence at end-of-treatment (weeks 6,9; primary end-point); 7-day point prevalence abstinence at weeks 9 and 24; sustained abstinence (weeks 6,24); change in body weight; and adverse events. Findings Rimonabant plus nicotine patch was superior to rimonabant plus placebo in validated continuous abstinence at weeks 6,9 (39.0% versus 21.3%; odds ratio 2.36, 95% confidence interval: 1.71,2.37; P < 0.01) and in all other efficacy measures. Mean end-of-treatment weight gain among quitters did not differ between groups (0.04 kg for combination versus 0.49 kg for rimonabant only, P = 0.15) and was similar in weight-concerned smokers. Serious adverse event rates did not differ between groups. Depression- and anxiety-related adverse events occurred in 32 (4.2%) and 44 (5.8%) subjects, respectively; eight (1.1%) and nine (1.2%) subjects stopped the drug due to depression and anxiety, respectively. Conclusions Adding a nicotine patch to rimonabant was well tolerated and increased smoking cessation rates over rimonabant alone. There was little post-cessation weight gain in either group, even among weight-concerned smokers, during drug treatment. [source] Depletion of tumor-induced Treg prior to reconstitution rescues enhanced priming of tumor-specific, therapeutic effector T cells in lymphopenic hostsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 11 2009Christian H. Poehlein Abstract We reported previously that vaccination of reconstituted, lymphopenic mice resulted in a higher frequency of tumor-specific effector T cells with therapeutic activity than vaccination of normal mice. Here, we show that lymphopenic mice reconstituted with spleen cells from tumor-bearing mice (TBM), a situation that resembles the clinical condition, failed to generate tumor-specific T cells with therapeutic efficacy. However, depletion of CD25+ Treg from the spleen cells of TBM restored tumor-specific priming and therapeutic efficacy. Adding back TBM CD25+ Treg to CD25, naïve and TBM donor T cells prior to reconstitution confirmed their suppressive role. CD25+ Treg from TBM prevented priming of tumor-specific T cells since subsequent depletion of CD4+ T cells did not restore therapeutic efficacy. This effect may not be antigen-specific as three histologically distinct tumors generated CD25+ Treg that could suppress the T-cell immune response to a melanoma vaccine. Importantly, since ex vivo depletion of CD25+ Treg from TBM spleen cells prior to reconstitution and vaccination fully restored the generation of therapeutic effector T cells, even in animals with established tumor burden, we have initiated a translational clinical trial of this strategy in patients with metastatic melanoma. [source] Aqueous fluids at elevated pressure and temperatureGEOFLUIDS (ELECTRONIC), Issue 1-2 2010A. LIEBSCHER Abstract The general major component composition of aqueous fluids at elevated pressure and temperature conditions can be represented by H2O, different non-polar gases like CO2 and different dissolved metal halides like NaCl or CaCl2. At high pressure, the mutual solubility of H2O and silicate melts increases and also silicates may form essential components of aqueous fluids. Given the huge range of P,T,x regimes in crust and mantle, aqueous fluids at elevated pressure and temperature are highly variable in composition and exhibit specific physicochemical properties. This paper reviews principal phase relations in one- and two-component fluid systems, phase relations and properties of binary and ternary fluid systems, properties of pure H2O at elevated P,T conditions, and aqueous fluids in H2O,silicate systems at high pressure and temperature. At metamorphic conditions, even the physicochemical properties of pure water substantially differ from those at ambient conditions. Under typical mid- to lower-crustal metamorphic conditions, the density of pure H2O is , the ion product Kw = 10,7.5 to approximately 10,12.5, the dielectric constant , = 8,25, and the viscosity , = 0.0001,0.0002 Pa sec compared to , Kw = 10,14, , = 78 and , = 0.001 Pa sec at ambient conditions. Adding dissolved metal halides and non-polar gases to H2O significantly enlarges the pressure,temperature range, where different aqueous fluids may co-exist and leads to potential two-phase fluid conditions under must mid- to lower-crustal P,T conditions. As a result of the increased mutual solubility between aqueous fluids and silicate melts at high pressure, the differences between fluid and melt vanishes and the distinction between fluid and melt becomes obsolete. Both are completely miscible at pressures above the respective critical curve giving rise to so-called supercritical fluids. These supercritical fluids combine comparably low viscosity with high solute contents and are very effective metasomatising agents within the mantle wedge above subduction zones. [source] THE CEO: A VISIBLE HAND IN WEALTH CREATION?JOURNAL OF APPLIED CORPORATE FINANCE, Issue 3 2000C. K. Prahalad Commensurate with the growth of their pay packages and public visibility, the role of the CEO in the corporate value creation process has increased significantly in recent years. This article argues that sustained wealth creation in a corporation has three distinct elements. The first and most basic is the selection of the lines of business in which to operate; this element is probably the most visible manifestation of CEO action in large corporations today. The second element is the value creation model, which answers the question: How is this particular set of businesses expected to add value over and above the sum of the values of each business or asset category standing alone? The third element is the internal governance system, which establishes the corporate structure and administrative processes of the firm and, perhaps even more important, defines the corporate values that drive the strategic and operational priorities of the different business units. The authors suggest that the essence of the work of the CEO is to develop and maintain a balanced relationship among these three elements of wealth creation and to ensure that the relationship evolves in the face of changing circumstances. CEOs are inevitably faced with dilemmas in managing this process,in particular, the need to balance continuity and change and to maintain the integrity of short-term performance disciplines while encouraging not only investment in growth opportunities (which can hurt near term performance), but also experimentation and collaboration among business units (which are difficult to measure and reward with most performance measurement and incentive schemes). Adding to the difficulties of managing such dilemmas, visibility and a strong public image are often thrust upon (if not sought by) CEOs, who must then determine how they can use that image to strengthen the commitment of their employees and investors. [source] BAKING PROPERTIES OF MILK PROTEIN-COATED WHEAT BRAN,JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2008CHARLES I. ONWULATA ABSTRACT Increasing the dietary fiber content of formulated foods will benefit the health and nutrition of consumers. The problem is that it is difficult to add substantial amounts of dietary fiber to formulated foods. Fiber absorbs significant amounts of water from surrounding ingredients creating texture problems such as soggy and dry patches in the foods. In this study, red wheat bran milled and sieved smaller than 140 microns was coated by spraying with a 50/50 emulsion of whey protein isolates (WPIs) and casein. WPI and casein emulsion was produced first by blending and shearing the milk proteins in ice and water and then evaporating under partial vacuum for 75 min at 45C. Cookies and muffins made with the milk protein-coated red wheat (MPCF) bran and the noncoated wheat bran (NCF), replacing 5, 10 and 15 wt % of the flour, were compared to control cookies and muffins made without added fiber. The water-holding capacity (WHC) of the MPCF and NCF was determined along with their moisture, color, hardness, and volume in the baked cookies and muffins. There was a significant (P < 0.01) improvement (250%) in loss of WHC of MPCF over NCF. In cookies, MPCF absorbed significantly less water and was slightly darker at 5 wt % substitution than NCF, but was between 12 to 60% higher in baked volume than the control. MPCF muffins were lighter in color and harder except for the 5 wt % muffins that were softer and higher in percent baked volume. Adding up to 15-g MPCF per 100 g batter can be added to baked cookies and muffins to increase fiber content and improve WHC and volume. PRACTICAL APPLICATIONS This study determined that coating wheat bran with specially treated dairy proteins reduced the amount of water the bran can absorb when added up to 15 wt% to formulations, or in the finished products, helping to maintain textural integrity of products. The intact wheat bran remains available for its functional health enhancing roles when consumed and digested. This knowledge allows the creation of nutritious high-fiber products with desirable texture. [source] Formation of Malonaldehyde, Formaldehyde, and Acetaldehyde in Apple Juice Induced by Ionizing RadiationJOURNAL OF FOOD SCIENCE, Issue 7 2002X. Fan And ABSTRACT: We investigated the effects of ionizing radiation on the formation of malonaldehyde (MA), formaldehyde (FA), and acetaldehyde (ACT) in apple juice. The formation of MA, FA, and ACT in both pasteurized and fresh juice increased with radiation dose. The G values (number of species formed per 100 eV absorbed) for MA, FA, and ACT in pasteurized juice were 0.0056, 0.061, and 0.044, respectively. MA concentration decreased rapidly during storage at 5°C, while ACT and FA did not. Irradiation-induced formation of MA, FA, and ACT decreased with decreasing irradiation temperature. Exclusion of oxygen during irradiation reduced formation of ACT and FA, but not MA. Adding 1000 ppm of ascorbate, sorbate, or sulfite to juice before irradiation also decreased MA formation. [source] A one-carbon modification of protein lysine associated with elevated oxidative stress in human substantia nigraJOURNAL OF NEUROCHEMISTRY, Issue 2 2006Erik Floor Abstract We describe for the first time a naturally occurring lysine modification that is converted to methyllysine by reduction with sodium borohydride. This modification is ,1.7 times as abundant in soluble proteins from human substantia nigra pars compacta as in proteins from other brain regions, possibly as a result of elevated oxidative stress in the nigra. Proteins from cultured PC12 cells exposed to oxidative stress conditions also contain elevated levels of this lysine modification. The abundance of the naturally occurring modification is roughly 0.08 nmoles/mg protein in either unstressed brain or PC12 cells. Modification levels remain stable in isolated proteins incubated for 2 h at 37°C in pH 7 buffer. We propose that the endogenous modification is the lysine Schiff base, ,- N -methylenelysine, and that lysine modifications may result from a reaction with formaldehyde in vivo. Rat brain contains ,60 nmoles/g wet weight of formaldehyde, which probably includes both free and reversibly bound forms. Adding ,35 µm HCHO to PC12 cell growth medium introduces methylenelysine modifications in cell proteins and impairs cell viability. The existence of this post-translational modification suggests new mechanisms of oxidative stress that may contribute to tissue degeneration, including loss of nigral dopamine neurons during normal aging and in Parkinson's disease. [source] Complete dissolution and hydrolysis of wood in hot waterAICHE JOURNAL, Issue 10 2008Zhen Fang Abstract When willow and water were heated rapidly (7,16°C/s) to high temperatures and high pressures, most of willow (90 vol %) dissolved in water at 341°C in 2.5 s without complete dissolution. Adding 0.8 wt % Na2CO3, complete dissolution of willow (concentration up to 35 vol %) was observed at 329,367°C and water densities of 322,787 kg/m3 (14,106 MPa) in 1.5 s. By cooling the solublized willow immediately, micron particles were obtained via precipitation. If heated further to 400°C, willow was completely hydrolyzed to sugars/sugar oligomers in 14.6 s at homogeneous conditions. A flow reactor was proposed to completely solubilize willow for the production of micron particles, sugars, bio-fuels and chemicals continuously. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] A study of collective motions in liquid tert -butanol from low-wavenumber Raman scatteringJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2009P. Sassi Abstract The collective properties of liquid tert -butyl alcohol (TBA) were analysed by low-wavenumber Raman (LWR) scattering spectroscopy. Vibrational and relaxation phenomena of this H-bonding system were assessed in pure liquid phase at different temperatures in the 15,70 °C range, and in solution with 2,2,-dimethyl butane (2,2,-DMB) and water as a function of composition in the 0.7,xTBA,0.9 range at constant temperature (T = 25 °C). The LWR spectrum of pure TBA (below 150 cm,1) was expressed by the dynamical (or Raman) susceptibility ???? and reproduced by curve fitting using three functional forms. The high-wavenumber band, whose intensity is poorly dependent on the temperature, was assigned to the ultrafast librational mode; the remaining components with an intensity that increased with temperature were attributed to relaxation dynamics in the range of picosecond (,slow' 3 ps) and sub-picosecond (,fast', 0.4 ps) timescales. Adding 2,2,-DMB to TBA had no significant effect on the intermolecular interactions in alcohol-rich solutions, with almost unchanged LWR scattering features. On the other hand, water added to TBA determined an increase in interactions, similar to the effect of a temperature decrease in pure liquid alcohol; this was clearly depicted by the LWR profiles. Moreover, through the analysis of the OH stretching bands of water in solution, the confinement of aqueous pools in the hydrophilic spaces of alcohol-rich solutions was confirmed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Forecasting volatility for options valuationOPEC ENERGY REVIEW, Issue 3 2006Mahdjouba Belaifa The petroleum sector plays a neuralgic role in the basement of world economies, and market actors (producers, intermediates, as well as consumers) are continuously subjected to the dynamics of unstable oil market. Huge amounts are being invested along the production chain to make one barrel of crude oil available to the end user. Adding to that are the effect of geopolitical dynamics as well as geological risks as expressed in terms of low chances of successful discoveries. In addition, fiscal regimes and regulations, technology and environmental concerns are also among some of the major factors that contribute to the substantial risk in the oil industry and render the market structure vulnerable to crises. The management of these vulnerabilities require modern tools to reduce risk to a certain level, which unfortunately is a non-zero value. The aim of this paper is, therefore, to provide a modern technique to capture the oil price stochastic volatility that can be implemented to value the exposure of an investor, a company, a corporate or a Government. The paper first analyses the regional dependence on oil prices, through a historical perspective and then looks at the evolution of pricing environment since the large price jumps of the 1970s. The main causes of oil prices volatility are treated in the third part of the paper. The rest of the article deals with volatility models and forecasts used in risk management, with an implication for pricing derivatives. [source] A randomized trial of delayed extubation for the reduction of reintubation in extremely preterm infants,PEDIATRIC PULMONOLOGY, Issue 2 2008Claude Danan MD Abstract Objective To compare immediate extubation versus delayed extubation after 36 hr in extremely low-birth weight infants receiving gentle mechanical ventilation and perinatal lung protective interventions. Our hypothesis was that a delayed extubation in this setting would decrease the rate of reintubation. Study design/Methodology A prospective, unmasked, randomized, controlled trial to compare immediate extubation and delayed extubation after 36 hr. Optimized ventilation in both groups included continuous tracheal gas insufflation (CTGI), prophylactic surfactant administration, low oxygen saturation target and moderate permissive hypercapnia. Successful extubation for at least 7 days was the primary criterion and ventilatory support requirements until 36 weeks gestational age the main secondary criteria. Patient selection Eighty-six infants under 28 weeks gestational age in a single neonatal intensive tertiary care unit. Results Delayed extubation (1.9,±,0.8 days vs. 0.5,±,0.7 days) did not improve the rate of successful extubation but had no long-term adverse effects. CTGI and the lung protective strategy we describe resulted in a very gentle ventilation. The rate of survival without bronchopulmonary dysplasia (BPD, defined as any respiratory support at 36 weeks gestational age) was similar in the two groups and remarkably high for the global population (78%) and for the subgroup of infants <1,000 g at birth (75%). Conclusions Adding 36 hr of optimized mechanical ventilation before first extubation does not improve the rate of successful extubation but has no adverse effects. Pediatr Pulmonol. 2008; 43:117,124. © 2007 Wiley-Liss, Inc. [source] DPCT: Adding to the Cardiac Predictive TerminologyACADEMIC EMERGENCY MEDICINE, Issue 10 2009Jonathan Singer MD No abstract is available for this article. [source] Biomass recycling from a riboflavin cultivation with B. subtilis: Lysis, extract production and testing as substrate in riboflavin cultivationBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2006Karlheinz Bretz Abstract Autolysis of riboflavin-producing B. subtilis can be induced by pH, lack of carbon source, and the buffer system. Stress factors like temperature shift or oxygen dearth enhance the autolysis process. After cultivation of a riboflavin-producing strain, the pH of the whole culture broth was adjusted to 6.5,7.5. At a temperature of 40°C, autolysis started after 1 h. Adding a defined amount of commercially available endo- and exo-proteases enhanced both auto- and proteo-lysis. Optimization of endo- and exo-protease concentrations and of the time increased the degree of proteolysis. Additionally, the amount of DNA and Protein trapped in the riboflavin crystals could be significantly reduced by autolysis. After autolysis, the cultivation broth was centrifuged and the supernatant was cross-flow filtrated with a cut off of 10 kDa. Using this autolysate instead of yeast extract as a medium component for riboflavin production with B. subtilis, a riboflavin yield of 77% was obtained in comparison with the standard cultivation on yeast extract. © 2006 Wiley Periodicals, Inc. [source] From rent seeking to human capital: a model where resource shocks cause transitions from stagnation to growthCANADIAN JOURNAL OF ECONOMICS, Issue 3 2008Nils-Petter Lagerlöf The latter is interpreted as trade or manufacturing. Rent seeking exerts negative externalities on the productivity of human capital. Adding shocks, in the form of fluctuations in the size of the contested resource, the model can replicate a long phase with stagnant incomes and high levels of rent seeking, interrupted by small, failed growth spurts, eventually followed by a permanent transition to a sustained growth path where rent seeking vanishes in the limit. The model also generates a rise and fall of the so-called natural resource curse: before the takeoff, an increase in the size of the contested resource has a positive effect on incomes; shortly after the takeoff, the effect is negative; and on the balanced growth path the growth rate of per capita income is independent of resource shocks. Les auteurs présentent un modèle de croissance où les agents divisent leur temps entre la chasse aux rentes (sous la forme de concurrence pour la ressource existante) et le travail productif dans le secteur du capital humain. Cette dernière activité peut se faire dans le commerce ou le secteur manufacturier. La chasse aux rentes a des effets externes négatifs sur la productivité du capital humain. Si l'on injecte des chocs prenant la forme de fluctuations dans la taille de la ressource contestée, le modèle peut générer une longue période durant laquelle les revenus stagnent et le niveau de chasse aux rentes est élevé, période interrompue par des petits sursauts de croissance qui tournent court, et suivie éventuellement par une transition permanente à un sentier de croissance soutenue où, à la limite, les activités de chasse aux rentes disparaissent. Le modèle génère aussi l'apparition et la disparition de la malédiction des ressources naturelles: avant que la croissance prenne son envol, un accroissement de la taille de la ressource contestée a un effet positif sur les revenus; peu après le décollage, l'effet est négatif; et sur le sentier de croissance équilibrée, le taux de croissance des revenus per capita est indépendant des chocs sur la ressource. [source] Phylogenetics, biogeography and classification of, and character evolution in, gamebirds (Aves: Galliformes): effects of character exclusion, data partitioning and missing dataCLADISTICS, Issue 6 2006Timothy M. Crowe The phylogenetic relationships, biogeography and classification of, and morpho-behavioral (M/B) evolution in, gamebirds (Aves: Galliformes) are investigated. In-group taxa (rooted on representatives of the Anseriformes) include 158 species representing all suprageneric galliform taxa and 65 genera. The characters include 102 M/B attributes and 4452 nucleic acid base pairs from mitochondrial cytochrome b (CYT B), NADH dehydrogenase subunit 2 (ND2), 12S ribosomal DNA (12S) and control region (CR), and nuclear ovomucoid intron G (OVO-G). Analysis of the combined character data set yielded a single, completely resolved cladogram that had the highest levels of jackknife support, which suggests a need for a revised classification for the phasianine galliforms. Adding 102 M/B characters to the combined CYT B and ND2 partitions (2184 characters) decisively overturns the topology suggested by analysis of the two mtDNA partitions alone, refuting the view that M/B characters should be excluded from phylogenetic analyses because of their relatively small number and putative character state ambiguity. Exclusion of the OVO-G partition (with >,70% missing data) from the combined data set had no effect on cladistic structure, but slightly lowered jackknife support at several nodes. Exclusion of third positions of codons in an analysis of a CYT B + ND2 partition resulted in a massive loss of resolution and support, and even failed to recover the monophyly of the Galliformes with jackknife support. A combined analysis of putatively less informative, "non-coding" characters (CYT B/ND2 third position sites + CR +12S + OVO-G sequences) yielded a highly resolved consensus cladogram congruent with the combined-evidence cladogram. Traditionally recognized suprageneric galliform taxa emerging in the combined cladogram are: the families Megapodiidae (megapodes), Cracidae (cracids), Numididae (guineafowls), Odontophoridae (New World quails) and Phasianidae (pheasants, pavonines, partridges, quails, francolins, spurfowls and grouse) and the subfamilies Cracinae (curassows, chachalacas and the horned guan), Penelopinae (remaining guans), Pavoninae sensu lato (peafowls, peacock pheasants and argus pheasants), Tetraoninae (grouse) and Phasianinae (pheasants minus Gallus). The monophyly of some traditional groupings (e.g., the perdicinae: partridges/quails/francolins) is rejected decisively, contrasted by the emergence of other unexpected groupings. The most remarkable phylogenetic results are the placement of endemic African galliforms as sisters to geographically far-distant taxa in Asia and the Americas. Biogeographically, the combined-data cladogram supports the hypothesis that basal lineages of galliforms diverged prior to the Cretaceous/Tertiary (K-T) Event and that the subsequent cladogenesis was influenced by the break-up of Gondwana. The evolution of gamebirds in Africa, Asia and the Americas has a far more complicated historical biogeography than suggested to date. With regard to character evolution: spurs appear to have evolved at least twice within the Galliformes; a relatively large number of tail feathers (, 14) at least three times; polygyny at least twice; and sexual dimorphism many times. © The Willi Hennig Society 2006. [source] Engaging Science Education Within Diverse CulturesCURRICULUM INQUIRY, Issue 3 2003James Gaskell At the heart of discussions about an appropriate school science in a diverse world are questions about the status of modern science versus other schemes for understanding the natural world. Does modern science occupy a privileged epistemological position with respect to alternative beliefs? There has been a movement from an emphasis on replacing students' ideas based on traditional cultures to one of respecting those ideas and adding to them an understanding of modern science ideas and an exploration of when each might be useful. Respecting both sets of explanations need not deny discussions about credibility in particular contexts. School science, however, is always located within wider educational and political structures. Broad elements of the community must be engaged in dialogue concerning what knowledge about the natural world is important, to whom, and for what purposes. [source] Obsessive,compulsive disorder: a review of the diagnostic criteria and possible subtypes and dimensional specifiers for DSM-V,DEPRESSION AND ANXIETY, Issue 6 2010James F. Leckman M.D. Abstract Background: Since the publication of the DSM-IV in 1994, research on obsessive,compulsive disorder (OCD) has continued to expand. It is timely to reconsider the nosology of this disorder, assessing whether changes to diagnostic criteria as well as subtypes and specifiers may improve diagnostic validity and clinical utility. Methods: The existing criteria were evaluated. Key issues were identified. Electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies. Results: This review presents a number of options and preliminary recommendations to be considered for DSM-V. These include: (1) clarifying and simplifying the definition of obsessions and compulsions (criterion A); (2) possibly deleting the requirement that people recognize that their obsessions or compulsions are excessive or unreasonable (criterion B); (3) rethinking the clinical significance criterion (criterion C) and, in the interim, possibly adjusting what is considered "time-consuming" for OCD; (4) listing additional disorders to help with the differential diagnosis (criterion D); (5) rethinking the medical exclusion criterion (criterion E) and clarifying what is meant by a "general medical condition"; (6) revising the specifiers (i.e., clarifying that OCD can involve a range of insight, in addition to "poor insight," and adding "tic-related OCD"); and (7) highlighting in the DSM-V text important clinical features of OCD that are not currently mentioned in the criteria (e.g., the major symptom dimensions). Conclusions: A number of changes to the existing diagnostic criteria for OCD are proposed. These proposed criteria may change as the DSM-V process progresses. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc. [source] New and experimental approaches to treatment of diabetic foot ulcers: a comprehensive review of emerging treatment strategiesDIABETIC MEDICINE, Issue 11 2004R. Eldor Abstract Diabetic foot ulcers occur in up to 15% of all diabetic patients and are a leading cause of nontraumatic amputation worldwide. Neuropathy, abnormal foot biomechanics, peripheral vascular disease and external trauma are the major contributors to the development of a foot ulcer in the diabetic patient. Therapy today includes repeated debridement, offloading, and dressings, for lower grade ulcers, and broad spectrum antibiotics and occasionally limited or complete amputation for higher grades, requiring a team effort of health care workers from various specialties. The large population affected by diabetic foot ulcers and the high rates of failure ending with amputation even with the best therapeutic regimens, have resulted in the development of new therapies and are the focus of this review. These include new off loading techniques, dressings from various materials, methods to promote wound closure using artificial skin grafts, different growth factors or wound bed modulators and methods of debridement. These new techniques are promising but still mostly unproven and traditional approaches cannot be replaced. New and generally more expensive therapies should be seen as adding to traditional approaches. [source] Forage collection, substrate preparation, and diet composition in fungus-growing antsECOLOGICAL ENTOMOLOGY, Issue 3 2010HENRIK H. DE FINE LICHT 1. Variation and control of nutritional input is an important selective force in the evolution of mutualistic interactions and may significantly affect coevolutionary modifications in partner species. 2. The attine fungus-growing ants are a tribe of more than 230 described species (12 genera) that use a variety of different substrates to manure the symbiotic fungus they cultivate inside the nest. Common ,wisdom' is that the conspicuous leaf-cutting ants primarily use freshly cut plant material, whereas most of the other attine species use dry and partly degraded plant material such as leaf litter and caterpillar frass, but systematic comparative studies of actual resource acquisition across the attine ants have not been done. 3. Here we review 179 literature records of diet composition across the extant genera of fungus-growing ants. The records confirm the dependence of leaf-cutting ants on fresh vegetation but find that flowers, dry plant debris, seeds (husks), and insect frass are used by all genera, whereas other substrates such as nectar and insect carcasses are only used by some. 4. Diet composition was significantly correlated with ant substrate preparation behaviours before adding forage to the fungus garden, indicating that diet composition and farming practices have co-evolved. Neither diet nor preparation behaviours changed when a clade within the paleoattine genus Apterostigma shifted from rearing leucocoprinous fungi to cultivating pterulaceous fungi, but the evolutionary derived transition to yeast growing in the Cyphomyrmex rimosus group, which relies almost exclusively on nectar and insect frass, was associated with specific changes in diet composition. 5. The co-evolutionary transitions in diet composition across the genera of attine ants indicate that fungus-farming insect societies have the possibility to obtain more optimal fungal crops via artificial selection, analogous to documented practice in human subsistence farming. [source] Limitation of nesting resources for ants in Colombian forests and coffee plantationsECOLOGICAL ENTOMOLOGY, Issue 5 2006INGE ARMBRECHT Abstract 1.,This study examines limitation of nesting resources for leaf-litter and twig-nesting ants as a mechanism of diversity loss across an intensification gradient of coffee production in Colombia. Twelve farms were selected and classified into four management types: forest, polygeneric shade coffee, monogeneric shade coffee, and sun coffee (unshaded coffee monocultures). 2.,At each of the farms, four treatment subplots were established at the corners of each of 10 25 m2 plots: (i) twig augmentation (adding 10 empty bamboo twigs); (ii) litter augmentation (tripling existing litter profile); (iii) twig and litter augmentation; and (iv) no manipulation control, for a total of 480 subplots. A twig addition experiment was also performed on coffee bushes. 3.,The results showed significantly more ant colonies in the forest and monogeneric shade coffee litter augmentation plots after 4 months. Litter-nesting ant species richness was higher in all three shade systems than in the sun coffee. The identities of ants nesting on coffee bushes were different from those in the soil level litter. Fewer species nested in bamboo twigs placed in litter in the most intensive systems. 4.,More ants nested in the resource addition treatments, and more ant species were found in forested habitats; however, a single mechanism cannot explain the observed patterns. It was concluded that a combination of bottom-up and top-down effects might lead to the loss of associated fauna with the intensification of these agroecosystems. [source] The Hope of a Critical Ethics: Teachers and LearnersEDUCATIONAL THEORY, Issue 3 2004Donald Blumenfeld-Jones The basic question of this essay is what motivates a person to act on behalf of the "ethical good"? Critical theorists (such as Max Horkheimer, Paulo Freire, and Sharon Welch) have proposed the educational development of critical rationality as the answer to this question, with Freire adding the notion of love and Welch adding the notion of "dangerous memory." These positions are both critiqued and used as a starting place for proposing a critical ethics with three bases: (1) Emmanuel Levinas's notion of ethical infinity (that is, a person is more than any category can reveal and categories entrap and harm the person), (2) the notion of creating a community based on "relational authority," and (3) the development of moral imagination. Descriptions of specific classroom situations ground the discussion in education. [source] Venture Capitalists' Decision to SyndicateENTREPRENEURSHIP THEORY AND PRACTICE, Issue 2 2006Sophie Manigart Financial theory, access to deal flow, selection, and monitoring skills are used to explain syndication in venture capital firms in six European countries. In contrast with U.S. findings, portfolio management motives are more important for syndication than individual deal management motives. Risk sharing, portfolio diversification, and access to larger deals are more important than selection and monitoring of deals. This holds for later stage and for early stage investors. Value adding is a stronger motive for syndication for early stage investors than for later stage investors, however. Nonlead investors join syndicates for the selection and value-adding skills of the syndicate partners. [source] Use of stable isotope-labelled cells to identify active grazers of picocyanobacteria in ocean surface watersENVIRONMENTAL MICROBIOLOGY, Issue 2 2009Jorge Frias-Lopez Summary Prochlorococcus and Synechococcus are the two most abundant marine cyanobacteria. They represent a significant fraction of the total primary production of the world oceans and comprise a major fraction of the prey biomass available to phagotrophic protists. Despite relatively rapid growth rates, picocyanobacterial cell densities in open-ocean surface waters remain fairly constant, implying steady mortality due to viral infection and consumption by predators. There have been several studies on grazing by specific protists on Prochlorococcus and Synechococcus in culture, and of cell loss rates due to overall grazing in the field. However, the specific sources of mortality of these primary producers in the wild remain unknown. Here, we use a modification of the RNA stable isotope probing technique (RNA-SIP), which involves adding labelled cells to natural seawater, to identify active predators that are specifically consuming Prochlorococcus and Synechococcus in the surface waters of the Pacific Ocean. Four major groups were identified as having their 18S rRNA highly labelled: Prymnesiophyceae (Haptophyta), Dictyochophyceae (Stramenopiles), Bolidomonas (Stramenopiles) and Dinoflagellata (Alveolata). For the first three of these, the closest relative of the sequences identified was a photosynthetic organism, indicating the presence of mixotrophs among picocyanobacterial predators. We conclude that the use of RNA-SIP is a useful method to identity specific predators for picocyanobacteria in situ, and that the method could possibly be used to identify other bacterial predators important in the microbial food-web. [source] Predicting ready biodegradability in the Japanese ministry of international trade and industry testENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2000Jay Tunkel Abstract Two new predictive models for assessing a chemical's biodegradability in the Japanese Ministry of International Trade and Industry (MITI) ready biodegradation test have been developed. The new methods use an approach similar to that in the existing BIOWIN© program, in which the probability of rapid biodegradation is estimated by means of multiple linear or nonlinear regression against counts of 36 chemical substructures (molecular fragments) plus molecular weight (mol wt). The data set used to develop the new models consisted of results (pass/no pass) from the MITI test for 884 discrete organic chemicals. This data set was first divided into randomly selected training and validation sets, and new coefficients were derived for the training set using the BIOWIN fragment library and mol wt as independent variables. Based on these results, the fragment library was then modified by deleting some fragments and adding or refining others, and the new set of independent variables (42 substructures and mol wt) was fit to the MITI data. The resulting linear and nonlinear regression models accurately classified 81% of the chemicals in an independent validation set. Like the established BIOWIN models, the MITI models are intended for use in chemical screening and in setting priorities for further review. [source] Demonstration of strong enterobacterial reactivity of CD4+CD25, T,cells from conventional and germ-free mice which is counter-regulated by CD4+CD25+ T,cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2004Monika Gad Abstract Unfractionated CD4+ T,cells from the gut-associated lymphoid tissue (GALT) and peripheral lymph nodes are unresponsive when exposed to enterobacterial antigens in vitro. Under similar conditions, CD4+ T,cells depleted in vivo or in vitro of CD4+CD25+ T,cells proliferate extensively. The CD4+CD25, T,cell reactivity depends on MHC class,II presentation, specific TCR stimulation, CD4 ligation, and antigen processing by antigen-presenting cells. The CD4+CD25, T,cells respond to autologousand heterologous enterobacterial antigens, but not to antigens from the feces of germ-free mice. Surprisingly, CD4+CD25, T,cells obtained from the GALT of germ-free mice also proliferate when exposed to enterobacterial antigens, and adding back the conventional or germ-free CD4+CD25+ T,cells to the enteroantigen-stimulated CD4+CD25, T,cells abolishes proliferation. As judged from carboxyfluorescein diacetate succinimidyl ester-labeling experiments, 4,5% of the CD4+CD25, T,cells respond to enteroantigen. The data show for the first time that CD4+CD25, T,cells with reactivity towards the enterobacterial flora and regulatory CD4+CD25+ T,cells are present in both conventional and germ-free mice. The data suggest that a significant proportion of the peripheral pool of CD4+CD25, T,cells express anti-enterobacterial reactivity, which, due to the presence of regulatory CD4+CD25+ T,cells, is kept in a quiescent state. [source] | ||||||||||||||||||||||||||||||||||||||||