bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Niacin on Cell Adhesion and Early Atherogenesis: Biochemical and Functional Findings in Endothelial Cells
Authors: Tavintharan Subramaniam , Lim Su Chi , Sum Chee Fang
Published: January 2009

Abstract:  Atherosclerotic cardiovascular disease is a major cause of morbidity and mortality. Increased expression of cell adhesion molecules (CAM) and their ligands mediate essential processes in atherogenesis. Niacin reduces atherosclerotic cardiovascular complications and total mortality. Further understanding is needed on effects of niacin on CAM, and its functional consequences. The aim of this study was to evaluate the effects of niacin on CAM expression and monocyte adhesion in endothelial cells. Endothelial cells (HUVEC) were cultured to reach 80–90% confluence before experiments were initiated. Cells were exposed to DME/F12 with selected concentrations of niacin. To elicit the expression of CAM, cells were stimulated by addition of tumour necrosis factor (TNF)‐α, interleukin (IL)‐1 or interferon‐γ. Lysate from the conditioned media was assayed for CAM. The effect of niacin on mRNA expression of ICAM‐1 was studied using semi‐quantitative analysis of ICAM‐1 mRNA. Adhesion assays were performed with flow cytometry to study the functional significance of the effects niacin on CAM expression. Niacin significantly reduced ICAM‐1 and PECAM‐1 protein levels basally, and reduced the cytokine‐induced rise in ICAM‐1, with a similar effect for TNF‐α‐induced PECAM‐1 rise. The decrease in TNF‐α‐induced rise in ICAM‐1 level was associated with a reduction of NF‐κB activation, a reduction in mRNA expression of ICAM‐1, and a functional reduction in monocyte adhesion to cultured endothelial cells. Niacin reduces CAM expression and monocyte adhesion to endothelial cells. Apart from its lipid‐modifying effects, these pleiotropic effects of niacin may potentially contribute to the beneficial effects of risk reduction for atherosclerotic disease.
Androgens and Erectile Function: A Case for Early Androgen Use in Postprostatectomy Hypogonadal Men
Authors: Khera Mohit
Published: January 2009

Introduction

Erectile dysfunction affects up to 80% of men following a radical prostatectomy (RP) and is a common concern for these patients. Currently, hypogonadal men are not treated with testosterone after a RP for fear of stimulating dormant prostate cancer cells even though there is little evidence to support this hesitancy. There is data, however, to support the use of testosterone to aid in faster and better recovery of erections following RP.

Aims

The aim of this article is to explore the relationship between testosterone replacement therapy (TRT) and erectile preservation following RP.

Main Outcome Measures

The results of findings in the literature on the association between testosterone and its role in preserving erectile function, particularly in men following RP.

Methods

This article reviews and evaluates the literature that demonstrates the role of testosterone in obtaining erections and preserving erectile function. Additional articles were reviewed to assess the role of testosterone in erectile preservation following RP.

Results

This review demonstrates that testosterone does play a role in erectile function, particularly for men who have undergone a RP. Testosterone has been shown to have an effect on nitric oxide synthase release, phosphodiesterase type 5 expression and activity, and in cavernosal nerve function, and to contribute to venoocclusive disease in the penis. All of these effects are of particular importance to men attempting to preserve erectile function following RP.

Conclusions

While the relationship between TRT and improvement in erectile function has been well established, the role of testosterone in men following RP may be of even greater significance. However, further studies are needed to assess the true safety of TRT following RP.
WTO Constraints on Domestic Support in Agriculture: Past and Future
Authors: Brink Lars
Published: January 2009

The domestic support provisions in the WTO Agreement on Agriculture originate in the 1958 Haberler Report. Economic analysis often overlooks the agreement's legally important distinctions. Few domestic support issues lead to dispute settlement proceedings. The Doha negotiations would result in more constraints on domestic support than the sole commitment on Total Aggregate Measurement of Support (AMS) in the present agreement: ceilings on overall trade‐distorting support and blue box payments, and also product‐specific caps. Some 18 members would reduce their Total AMS commitments, and 25 would reduce the de minimis percentages. Most members would not reduce their constraints at all or only little. If today's developing countries continue to grow as they did in recent decades, their capacity to support agriculture increases significantly. If they then choose to support agriculture as today's developed countries did at the same stage of economic development, the future WTO constraints on trade‐distorting domestic support would allow them to provide considerably more such support than developed countries.

Les règles sur le soutien interne de l'Accord sur l'agriculture de l'OMC tirent son origine du rapport ≪Haberler≫ de 1958. L'analyse économique oublie souvent les distinctions d'importance juridique de l'accord. Peu de questions en soutien interne entraînent des procédures de règlement des différends. Les négociations de Doha se solderaient par plus de contraintes sur le soutien que le seul engagement de l'accord actuel, celui sur la mesure globale de soutien (MGS) totale. Ces contraintes comprennent des plafonds sur le soutien interne global ayant des effets de distorsion des échanges et sur les paiements dans la boîte bleue, ainsi que des plafonds par produit. Environ 18 membres réduiraient leurs engagements sur la MGS totale, et 25 membres réduiraient les pourcentages de minimis. La plupart des membres ne réduiraient pas leurs engagements ou les réduiraient seulement un peu. Si la croissance économique des pays, qui aujourd'hui sont en voie de développement, continue au même taux que dans les décennies récentes, leur capacité de soutenir leur agriculture augmente. S'ils choisissaient dans l'avenir de soutenir leur agriculture, comme l'ont fait les pays qui sont aujourd'hui les pays développés lorsqu'ils se trouvaient au même stage de développement, les contraintes futures de l'OMC sur le soutien interne faussant les échanges permettraient aux pays en voie de développement d'accorder de tel soutien dans des montants considérablement plus importants que ceux des pays développés.
A Dynamic Approach to Estimating and Testing Separability in U.S. Demand for Imported and Domestic Meats
Authors: Boonsaeng Tullaya , Wohlgenant Michael K.
Published: January 2009

The paper develops dynamic model of demand for domestic and imported meats and compares the performance of the dynamic model called the general AIDS error correction model (GAECM) with the static linear approximate almost ideal demand system (LA/AIDS) model. A test for separability is developed based on the long‐run solution to the dynamic model. The results indicate rejection of the static model in favor of the dynamic model. Homogeneity and symmetry are shown to hold for the dynamic model but are strongly rejected for the static model. Finally, separability between domestic and imported meats is rejected for all models at the 5% level of significance. However, the results of the dynamic model based on the corrected likelihood test with a low p‐value (p= 0.038) indicate that rejection of separability is borderline.

Le présent article porte sur l'élaboration d'un modèle dynamique de la demande de viandes produites au pays et de viandes importées, et compare la performance du modèle dynamique appelé modèle général de correction d'erreur AIDS avec le modèle statique LA/AIDS. Un test de séparabilité est élaboré d'après la solution à long terme du modèle dynamique. Les résultats indiquent le rejet du modèle statique en faveur du modèle dynamique. L'homogénéité et la symétrie sont valables pour le modèle dynamique, mais sont fortement rejetées dans le cas du modèle statique. Finalement, la séparabilité entre les viandes produites au pays et les viandes importées est rejetée pour tous les modèles à un seuil de signification de 5 p. 100. Cependant, les résultats du modèle dynamique, fondés sur la correction du test du rapport des vraisemblances avec une faible valeur p (p = 0,038), indiquent que le rejet de la séparabilité se situe à la limite.
Art and Negative Affect
Authors: Smuts Aaron
Published: January 2009

Why do people seemingly want to be scared by movies and feel pity for fictional characters when they avoid situations in real life that arouse these same negative emotions? Although the domain of relevant artworks encompasses far more than just tragedy, the general problem is typically called the paradox of tragedy. The paradox boils down to a simple question: If people avoid pain then why do people want to experience art that is painful? I discuss six popular solutions to the paradox: conversion, control, compensatory, meta‐response, catharsis, and rich experience theories.
Expression of Dense‐core Vesicles and of Their Exocytosis Are Governed by the Repressive Transcription Factor NRSF/REST
Authors: D'Alessandro Rosalba , Klajn Andrijana , Meldolesi Jacopo
Published: January 2009

The mechanism by which neurons and neurosecretory cells govern the expression and the exocytic discharge of their clear and dense‐core vesicles had remained unclear until recently when studies in the neurosecretory cell model PC12 revealed these processes to be orchestrated by the transcriptional repressor neuron restrictive silencer factor (NRSF)/repressor element‐1 silencing transcription factor (REST). In wild‐type PC12 fully competent for neurosecretion, NRSF/REST is low. The genes of the proteins involved in neurosecretion [from the secretory to vesicle membrane and plasma membrane proteins, including the soluble N‐ethylmaleimide‐sensitive factor attachment protein receptors (SNAREs) of exocytosis] were all repressed by increases of NRSF/REST expression to various extents when the increase was only a fewfold but were completely or almost completely repressed when the increase was large, as in spontaneously defective PC12 clones. In the first case the dense‐core vesicles were still competent for exocytosis but were smaller and less dense than in wild‐type cells; in the second they were no longer visible but did reappear when the repression was attenuated by transfection of a dominant‐negative construct of NRSF/REST combined with a secretory chromogranin or strengthened by treatment with a blocker of NRSF/REST‐associated enzymes, the histone deacetylases.
Rescuing the Subprime Meltdown in Insulin Exocytosis in Diabetes
Authors: Kwan Edwin P. , Gaisano Herbert Y.
Published: January 2009

Neuroendocrine pancreatic islet β‐cells secrete the hormone insulin in response to glucose stimulation and adapt efficiently to increased demand by peripheral tissues to maintain glucose homeostasis. Insulin is packed within dense‐core granules, which traffic and dock onto the plasma membrane whereby a Ca2+ stimulus evokes exocytosis by soluble N‐ethylmaleimide‐sensitive factor attachment protein receptor (SNARE), complex‐mediated, membrane fusion. Recent studies have unveiled postdocking steps mediated by “priming” factors that influence SNARE complex assembly to confer fusion readiness to the docked granules. This review will summarize recent insights into the priming role for Munc13 in the exocytosis of insulin granules. We present evidence for the interaction of Munc13‐1 with exocytotic substrates involved in cAMP‐mediated potentiation of insulin release, the latter we show to mediate enhanced granule‐to‐granule fusion events underlying compound exocytosis. We thus also further review the current understanding of granule‐to‐granule fusion. As agents acting on cAMP signaling are clinically used to augment insulin release in diabetes, this better understanding of priming steps may reveal additional novel therapeutic strategies to increase the capacity for insulin release to improve the treatment of diabetes.
Single Molecule Probing of SNARE Proteins by Atomic Force Microscopy
Authors: Liu Wei , Parpura Vladimir
Published: January 2009

Atomic force microscopy (AFM) in force spectroscopy mode has recently emerged as a technique of choice for studying mechanical interactions between the proteins of the core soluble N‐ethylmaleimide‐sensitive fusion protein attachment protein attachment protein receptor (SNARE) complex. In these experiments, the rupture force, extension, spontaneous dissociation time, and interaction energy for SNARE protein–protein interactions can be obtained at the single molecule level. These measurements, which are complementary to results and conclusions drawn from other techniques, improve our understanding of the role of the SNARE complex in exocytosis.
Voltage‐gated Potassium Channel as a Facilitator of Exocytosis
Authors: Feinshreiber Lori , Singer‐Lahat Dafna , Ashery Uri , Lotan Ilana
Published: January 2009

Voltage‐gated ion channels are well characterized for their function in excitability signals. Accumulating studies, however, have established an ion‐independent function for the major classes of ion channels in cellular signaling. During the last few years we established a novel role for Kv2.1, a voltage‐gated potassium (Kv) channel, classically known for its role of repolarizing the membrane potential, in facilitation of exocytosis. Kv2.1 induces facilitation of depolarization‐induced release through its direct interaction with syntaxin, a protein component of the exocytotic machinery, independently of the potassium ion flow through the channel's pore. Here, we review our recent studies, further characterize the phenomena (using chromaffin cells and carbon fiber amperometry), and suggest plausible mechanisms that can underlie this facilitation of release.
Exocytosis, Mediatophore, and Vesicular Ca2+/H+ Antiport in Rapid Neurotransmission
Authors: Dunant Yves , Cordeiro J. Miguel , Gonçalves Paula P.
Published: January 2009

In rapid synapses, neurotransmitter quanta are emitted in less than 100 μs, often at a high frequency. Using fast cryofixation of synapses, we found a very brief (2–3 ms) change affecting intramembrane particles in presynaptic membrane. Vesicle openings also occurred but after a significant delay. The particle change is most probably linked to mediatophore, a proteolipid of 220 kDa. Mediatophore aggregates were demonstrated in active zones of the presynaptic membrane. Reconstituted in liposomes, Xenopus oocytes, and neuroblastoma cells, mediatophore releases acetylcholine in a Ca2+‐dependent and quantal manner, mimicking physiological release. In restricted presynaptic “nanodomains,” Ca2+ concentration explosively reaches a high level and then vanishes with a time constant of 300–400 μs. Among the processes contributing to the fast phase of Ca2+ buffering, a vesicular Ca2+/H+ antiport plays a major role. Energized by the Vesicular‐ATPase‐dependent proton gradient, the antiport has a low affinity for Ca2+. We inactivated the Ca2+/H+ antiport using bafilomycin A1, which annihilates the proton gradient. As a result, the postsynaptic potential was increased in duration for about 3 ms, an effect caused by persistence of transmitter release. A similar change was obtained by replacing extracellular Ca2+ by strontium, which inhibits the antiport. The antiport function, therefore, is to abbreviate the presynaptic Ca2+ signal, making transmitter release briefer. This allows transmission to operate at high frequency. Following a brief period of stimulation, calcium transiently accumulates in synaptic vesicles where it is exchanged against transmitter. Calcium is subsequently cleared from the terminal, most probably by exocytosis.
The Coffin–Lowry Syndrome‐associated Protein RSK2 Controls Neuroendocrine Secretion through the Regulation of Phospholipase D1 at the Exocytotic Sites
Authors: Zeniou‐Meyer Maria , Béglé Aurélie , Bader Marie‐France , Vitale Nicolas
Published: January 2009

Together with the soluble N‐ethylmaleimide‐sensitive factor attachment protein receptor (SNARE) proteins, fusogenic cone‐shaped lipids, such as phosphatidic acid (PA), have been recently shown to be important actors in membrane fusion during exocytosis. Phospholipase D (PLD) appears to be the main provider of PA at the exocytotic site in neuroendocrine cells. We show here that ribosomal S6 kinase 2 (RSK2) stimulates PLD activity through the phosphorylation of Thr147 in the PLD1 amino‐terminal Phox‐homology domain. In PC12 cells, depletion of RSK2 dramatically prevents PA synthesis at exocytotic sites and inhibits hormone release. Expression of PLD1 phosphomimetic mutants fully restores secretion in cells depleted of RSK2, suggesting that RSK2 is a critical upstream signaling element in the activation of PLD1 to produce the lipids required for exocytosis.
Regulated Exocytosis and Vesicle Trafficking in Astrocytes
Authors: Kreft Marko , Potokar Maja , Stenovec Matjaž , Pangršič Tina , Zorec Robert
Published: January 2009

Astrocytes are increasingly viewed as crucial cells supporting and integrating brain functions. It is thought that the release of gliotransmitters into the extracellular space by regulated exocytosis supports a significant part of communication between astrocytes and neurons. Prior to exocytosis, the membrane‐bound vesicles are transported through the astrocyte cytoplasm. Our recent studies have revealed new insights into vesicle trafficking in the cytoplasm of astrocytes and are reviewed in this article. The prefusion mobility of fluorescently labeled peptidergic vesicles was studied in cultured rat and mouse astrocytes. Vesicle delivery to the plasma membrane involved an interaction with the cytoskeleton, in particular with microtubules and actin filaments. Interestingly, vesicle mobility in mouse astrocytes deficient in intermediate filaments show impaired directionality of peptidergic vesicle mobility. To explore whether stimuli that increase the concentration of free calcium ions in the cytoplasm triggered vesicular ATP release from astrocytes, human embryonic kidney‐293T cells transfected with a P2X3 receptor were used as sniffers to detect ATP release. Glutamate stimulation of astrocytes was followed by an increase in the incidence of small, transient, inward currents in sniffer cells, reminiscent of postsynaptic quantal events observed at synapses. Some of the membrane‐bound vesicles are retrieved from the plasma membrane to be recycled back into the cytosol. Trafficking velocity of postfusion (recycling) atrial natriuretic peptide vesicles was one order of magnitude slower in comparison to the mobility of prefusion vesicles. However, transport of all vesicle types studied required an intact cytoskeleton.
The Fusion Pore and Vesicle Cargo Discharge Modulation
Authors: Vardjan Nina , Stenovec Matjaž , Jorgačevski Jernej , Kreft Marko , Grilc Sonja , Zorec Robert
Published: January 2009

Exocytosis, the merger of the vesicle membrane with the plasma membrane, is thought to mediate the release of hormones and neurotransmitters from secretory vesicles. The work of Bernard Katz and colleagues decades ago considered that vesicle cargo discharge initially requires the delivery of secretory vesicles to the plasma membrane where vesicles dock and are primed for fusion with the plasma membrane. Then, upon stimulation, the vesicle and the plasma membranes fuse to form a transient fusion pore through which cargo molecules diffuse out of the vesicle lumen into the extracellular space. Katz and colleagues considered this process to occur in an all‐or‐none fashion. However, recent studies show that this may not be so simple. The aim of this overview is to highlight the novel findings that indicate that fusion pores are subject to regulations, which affect the release competence of a single vesicle. Here we discuss the elementary properties of spontaneous and stimulated peptidergic vesicle discharge, which appears to be modulated, at least in pituitary lactotrophs, by fusion pore conductance (pore diameter) and fusion pore gating (kinetics).
Compound Exocytosis in Pituitary Cells
Authors: Vardjan Nina , Jorgačevski Jernej , Stenovec Matjaž , Kreft Marko , Zorec Robert
Published: January 2009

Neurotransmitter and hormone release from vesicles involves fusion between the vesicle and the plasma membranes, a process termed exocytosis. Recently we reported that most of the spontaneous and stimulated exocytotic events in pituitary lactotrophs are transient and repetitive, appearing in bursts lasting more than 100 s. However, whether this is also the case in compound vesicle‐to‐vesicle exocytosis is unknown. Here we investigated compound exocytotic events in resting and stimulated lactotrophs by using optical and cell‐attached patch‐clamp capacitance measurements. Elementary compound exocytotic events were characterized by multiple‐amplitude on‐steps in synaptopHluorin fluorescence and in membrane capacitance signals. Multiple‐amplitude on‐steps appeared either as a relatively large upward step, indicating that vesicles were fused with each other prior to fusion of the vesicle membrane with the plasma membrane (multivesicular exocytosis), or as a time‐dependent stepwise signal increase, indicating sequential fusion of two or more vesicles with the plasma membrane (sequential exocytosis). In the majority of membrane capacitance recordings (>90%), multiple‐amplitude on‐steps terminated as multiple‐amplitude off‐steps. These complex amplitude events were repetitive, indicating that transient fusion pore openings reflect repetitive interactions of a single vesicle or vesicles in a cluster with the plasma membrane. Out of many mechanisms, these interactions may enable the diffusion of fusion proteins from the plasma membrane to the membrane of the primary fused vesicles, consequently enabling vesicle‐to‐vesicle fusion. The incidence of compound exocytotic events increased by 33% after stimulation, which is consistent with the enhanced efficiency of hormone secretion after the stimulus.
‘The Rise of the Historical Consciousness’
Authors: Wolfart Johannes C.
Published: January 2009

‘The rise of the historical consciousness’ represents a grand narrative that is closely linked to other meta‐histories, especially modernization and secularization. The idea that critical thought about history arose uniquely in a certain place (Europe, particularly Germany) and at a certain time (the Enlightenment of the eighteenth century) is widespread and powerful. As an ideology this notion, which is also known as historicism, actually operates in two principal directions. First, it poses a direct challenge to other powerful epistemological systems of the West, especially those supporting the establishments of science and religion. Second, historicism is a key element in the imperialism, cultural and otherwise, by means of which European and American societies have dominated the rest of the world in the capitalist age. Finally, this dual operation of historicism means not only that it has come in for much criticism, especially in recent decades, but that such criticism has come from both ends of the very wide spectrum in contemporary cultural politics. Rather confusingly, historicism remainsboththe darling and the bête noire ofboth‘conservative’ theological apologists and ‘radical’ postcolonial critics.
The Impact of Agglomeration and Storage on Flavor and Flavor Stability of Whey Protein Concentrate 80% and Whey Protein Isolate
Authors: Wright B.J. , Zevchak S.E. , Wright J.M. , Drake M.A.
Published: January 2009

ABSTRACT: The impact of agglomeration on flavor and flavor stability of whey protein concentrates 80% (WPC80) and whey protein isolates (WPI) has not been widely addressed. This study examined the impact of agglomeration on the flavor and flavor stability of commercial WPC80 and WPI across 18 mo of storage. Duplicate agglomerated and nonagglomerated WPC80 and WPI were collected from 4 facilities and stored at 21 °C, 50% relative humidity. Volatile analysis using solid phase microextraction (SPME) with gas chromatography‐mass spectrometry (GC‐MS) and descriptive sensory analysis were conducted every 2 mo. Solubility index, bulk volume, dispersibility, moisture, and color (L,a,b) were tested every 3 or 6 mo. Consumer acceptance testing with protein beverages was conducted with fresh and stored whey proteins. Higher intensities and more rapid development of lipid oxidation flavors (cardboard, raisin/brothy, cucumber, and fatty) were noted in agglomerated powders compared to nonagglomerated powders (P< 0.05). Volatile analysis results confirmed sensory results, which indicated increased formation of aldehydes and ketones in agglomerated products compared to nonagglomerated powders (P< 0.05). Consumer acceptance scores for protein beverages were lower for beverages made with agglomerated WPC80 stored for 12 mo and agglomerated or nonagglomerated WPI stored for 18 mo compared to fresh products while trained panelists detected differences among beverages and rehydrated proteins earlier. Agglomeration with or without lecithin decreased the storage stability of whey proteins. These results indicate that the optimum shelf life at 21 °C for nonagglomerated whey proteins is 12 to 15 mo and 8 to 12 mo for agglomerated whey proteins.
Factors Affecting the Hydroxycinnamate Decarboxylase/Vinylphenol Reductase Activity of Dekkera/Brettanomyces: Application for Dekkera/Brettanomyces Control in Red Wine Making
Authors: Benito S. , Palomero F. , Morata A. , Calderón F. , Suárez‐Lepe J.A.
Published: January 2009

ABSTRACT:  The growth of Dekkera/Brettanomyces yeasts during the ageing of red wines—which can seriously reduce the quality of the final product—is difficult to control. The present study examines the hydroxycinnamate decarboxylase/vinylphenol reductase activity of different strains of Dekkera bruxellensis and Dekkera anomala under a range of growth‐limiting conditions with the aim of finding solutions to this problem. The yeasts were cultured in in‐house growth media containing different quantities of growth inhibitors such as ethanol, SO2, ascorbic acid, benzoic acid and nicostatin, different sugar contents, and at different pHs and temperatures. The reduction of p‐coumaric acid and the formation of 4‐ethylphenol were periodically monitored by HPLC‐PDA. The results of this study allow the optimization of differential media for detecting/culturing these yeasts, and suggest possible ways of controlling these organisms in wineries.
Primary Reaction Dynamics of Proteorhodopsin Mutant D97N Observed by Femtosecond Infrared and Visible Spectroscopy†
Authors: Verhoefen Mirka‐Kristin , Neumann Karsten , Weber Ingrid , Glaubitz Clemens , Wachtveitl Josef
Published: January 2009

Femtosecond time‐resolved spectroscopy in the visible and IR range was utilized to study the primary reaction dynamics of the proteorhodopsin (PR) D97N mutant in comparison with wild type PR at different pH values. The analysis of the data obtained in the mid‐IR closely resembles the results for wild type PR. The observation of the first ground state intermediate K is initially obscured by a complex reaction scheme of vibrational relaxation and heating effects, but its spectral signature clearly emerges at long delay times. In the visible range, a biexponential decay of the excited state within 30 ps and the formation of the K photoproduct is observed. The decay time constants derived for the D97N mutant in D2O are slightly larger than in H2O due to H/D exchange. This kinetic isotope effect is even less pronounced than for wild type PR at pH 6. These results support the current notion of a pH dependent hydrogen bonding network in the retinal binding pocket of PR and a weaker interaction between the retinal Schiff base and the counter ion complex compared to bacteriorhodopsin.
Inactivation of Virulent Burkholderia pseudomallei by Sunlight
Authors: Sagripanti Jose‐Luis , Levy Avram , Robertson Jeannie , Merritt Adam , Inglis Timothy J. J.
Published: January 2009

The goal of this study was to determine the sensitivity of virulent Burkholderia pseudomallei to natural sunlight. We describe solar dosimetry calibrated to integrate radiation between 295 and 305 nm and an exposure system that minimizes thermal effects on bacterial cells. Burkholderia pseudomallei cells were either exposed to sunlight in UV transparent dishes or maintained in the dark covered by opaque foil. The cells maintained in the dark remained at constant levels for the duration of all experiments. The exposed cells nearby were killed with a kinetic studied through 5 Log10 inactivation. We found that cells in stationary phase of growth were nearly two‐fold more resistant to sunlight than cells in lag or exponential growth. A virulent strain of B. pseudomallei that produced mucoid colonies showed sensitivity to sunlight similar to both a virulent strain that produced nonmucoid colonies and a strain of B. thailandensis. The inactivation of B. pseudomallei by sunlight in different types of water of environmental relevance or inside amoebae was investigated. The sensitivity of virulent B. pseudomallei was calculated and its comparison with previous studies employing monochromatic germicidal light (254 nm) is discussed. This may be the first report in the open literature of the inactivation of a virulent biological threat agent by natural sunlight. These data should assist in estimating the risk for contracting melioidosis and in predicting the time period during which B. pseudomallei remains infectious after an accidental or intentional release in the environment.
Historiometry in Personality and Social Psychology
Authors: Simonton Dean Keith
Published: January 2009

Historiometry is one of the oldest methods in personality and social psychology. In fact, the first professional publication in experimental social psychology also incorporated a historiometric study. The present review article begins by describing the nature of the technique with respect to unit definition and sampling, the several approaches to measuring variables, and the correlational nature of the statistical analyses. This description also pinpoints some of the unique characteristics of the approach. These attributes and other attributes are then illustrated using the historiometric research on assessed leadership of US presidents. This research has converged on a single predictive equation that has been successfully replicated and extended over a quarter century of research. The article closes with a brief evaluation of historiometry's future prospects in the field.
Distributed Connectionist Models in Social Psychology
Authors: Smith Eliot R.
Published: January 2009

Distributed connectionist models of mental representation (also termed PDP or parallel distributed processing, or ANN or artificial neural networks) constitute a fundamental alternative to the associative or schematic models that have been much more prevalent in social psychology. A connectionist model is made up of a large number of very simple processing units, richly interconnected and able to send signals to each other depending on their momentary activation levels. No individual processing unit represents a meaningful concept; instead, overall patterns of activation hold representational meaning. This article emphasizes the novel properties of connectionist representation that might appeal to theorists and researchers in social psychology, including their context sensitivity and flexibility, ability to represent prototypes and exemplars within a single network, and ability to determine whether a stimulus is familiar even before the stimulus can be identified or categorized.
Involvement of PI3K/PTEN/AKT/mTOR pathway in invasion and metastasis in hepatocellular carcinoma: Association with MMP‐9
Authors: Chen Jing‐song , Wang Qian , Fu Xin‐hui , Huang Xiao‐Hui , Chen Xi‐lin , Cao Liang‐qi , Chen Lian‐zhou , Tan Hao‐xiang , Li Wen , Bi Jiong , Zhang Long‐juan
Published: January 2009

Aim:  To investigate the status of Phosphatidylinositol 3‐kinase (PI3K)/PTEN/AKT/mammalian target of rapamycin (mTOR) pathway and its correlation with clinicopathological features and matrix metalloproteinase‐2, ‐9 (MMP‐2, 9) in human hepatocellular carcinoma (HCC).

Methods:  PTEN, Phosphorylated AKT (p‐AKT), Phosphorylated mTOR (p‐mTOR), MMP‐2, MMP‐9 and Ki‐67 expression levels were evaluated by immunohistochemistry on tissue microarrays containing 200 HCCs with paired adjacent non‐cancerous liver tissues. PTEN, MMP‐2 and MMP‐9 mRNA levels were determined by real‐time RT‐PCR in 36 HCCs. The relationships between PI3K/PTEN/AKT/mTOR pathway and clinicopathological factors and MMP‐2, 9 were analyzed in HCC.

Results:  In HCC, PTEN loss and overexpression of p‐AKT and p‐mTOR were associated with tumor grade, intrahepatic metastasis, vascular invasion, TNM stage and high Ki‐67 labeling index (P < 0.05). PTEN loss was correlated with p‐AKT, p‐mTOR and MMP‐9 overexpression. Furthermore, PTEN and MMP‐2, 9 mRNA levels were down‐regulated and up‐regulated in HCC compared with paired non‐cancerous liver tissues, respectively (P < 0.01). PTEN, MMP‐2 and MMP‐9 mRNA levels were correlated with tumor stage and metastasis. There was an inverse correlation between PTEN and MMP‐9 mRNA expression. However, PI3K/PTEN/AKT/mTOR pathway was not correlated with MMP‐2.

Conclusions:  PI3K/PTEN/AKT/mTOR pathway, which is activated in HCC, is involved in invasion and metastasis through up‐regulating MMP‐9 in HCC.
Serum concentration of 27‐hydroxycholesterol predicts the effects of high‐cholesterol diet on plasma LDL cholesterol level
Authors: Hirayama Takeshi , Mizokami Yuji , Honda Akira , Homma Yasuhiko , Ikegami Tadashi , Saito Yoshifumi , Miyazaki Teruo , Matsuzaki Yasushi
Published: January 2009

Aim:  The effect of dietary cholesterol on plasma cholesterol concentrations varies widely among individuals. Recent studies suggest that the synthesis of oxysterols is up‐regulated when tissue cholesterol is saturated. The present study was undertaken to test the hypothesis that a serum high concentration of 27‐hydroxycholesterol, one of the oxysterols, reflects positive cholesterol balance in the body and predicts intolerance to a high‐cholesterol diet.

Methods:  In 30 subjects, 750 mg/day of cholesterol was added for 4 weeks to the ordinary diet. Blood samples were collected at the start and finish of the supplementation. Serum sterol and oxysterol concentrations were measured by high‐resolution GC‐MS.

Results:  A receiver operating characteristic curve was drawn and the cutoff point (80 ng/mg cholesterol) was chosen to maximize sensitivity (81.3%) and specificity (64.3%) for predicting a positive change of LDL cholesterol concentration after cholesterol loading. Subjects with higher serum 27‐hydroxycholesterol concentrations (≥ 80 ng/mg cholesterol) showed significantly (P < 0.05) high values for the change of LDL cholesterol concentration (+7.4 ± 3.4%, mean ± SEM, n = 17) compared with those with lower 27‐hydroxycholesterol levels (−5.3 ± 2.7%, n = 13).

Conclusions:  In subjects with high serum 27‐hydroxycholesterol concentrations were unable to adapt to a high‐cholesterol diet. The concentration of serum 27‐hydroxycholesterol appears to reflect cholesterol saturation in the body and predicts to some extent a responsiveness to dietary cholesterol.
Synthesis of Multistable Equilibrium Compliant Mechanisms Using Combinations of Bistable Mechanisms
Authors: Oh Young Seok , Kota Sridhar
Published: January 2009

In this paper, we present a mathematical approach to synthesize multistable compliant mechanisms by combining multiple bistable equilibrium mechanisms. More specifically, we identify and categorize various types of bistabilities by characterizing the essential elements of their complicated deformation pattern. The behavior of a bistable compliant mechanism, in general, is highly nonlinear. Using combinations of such nonlinearities to capture the behavior of multistable (more than two stable positions) mechanisms can be quite challenging. To determine multistable behavior, our simplified mathematical scheme captures the essential parameters of bistability, such as the load-thresholds that cause the jump to the next stable position. This mathematical simplification enables us to characterize bistable mechanisms by using piecewise lower-order polynomials and, in turn, synthesize multistable mechanisms. Three case studies involving combinations of two, three, and four bistable behaviors are presented for the purpose of generating multistable mechanisms with up to 16 stable positions. The methodology enables us to design a compliant mechanism with a desired number of stable positions. A design example of a quadristable equilibrium rotational compliant mechanism consisting of two bistable submechanisms is presented to demonstrate the effectiveness of the approach.
Optimization of Support Locations of Beam and Plate Structures Under Self-Weight by Using a Sprung Structure Model
Authors: Jang Gang-Won , Shim Ho Seong , Kim Yoon Young
Published: January 2009

To find support locations minimizing uneven deformation is an important design issue in a large plate under self-weight. During the imprinting process of LCD panels, for instance, a large variation in the deflection of an LCD panel due to its self-weight deteriorates the quality of nanoscale imprinted lines. Motivated by this need, this research aims to develop an efficient gradient-based optimization method of finding optimal support locations of beam or plate structures under self-weight. To use a gradient-based algorithm, the support locating problem is formulated with continuous design variables. In this work, a beam or plate structure is assumed to be supported by a set of distributed springs, which are attached to all nodes of the discretized model of a given structure. The spring stiffness is made to vary continuously as a function of the design variable in which unsupported and supported states of a structure are represented with springs having limit stiffness values. Because elastically supported structures exhibit considerably different structural behaviors from structures without elastic supports, it is difficult to select an objective function fulfilling the design goal and ensuring convergence to distinct supported-unsupported states without ambiguous intermediate states. To address this issue, an extensive study is conducted and an appropriate objective function is then suggested. An optimization formulation using the objective function is presented and several numerical problems are considered to check the validity and usefulness of the developed formulation.
A Closed-Form Planet Load Sharing Formulation for Planetary Gear Sets Using a Translational Analogy
Authors: Ligata H. , Kahraman A. , Singh A.
Published: January 2009

A simplified discrete model to predict load sharing among the planets of a planetary gear set having carrier planet position errors is presented in this study. The model proposes a translational representation of the torsional system and includes any number of planets positioned at any spacing configuration. The discrete model predictions are validated by comparing them to (i) the predictions of a deformable-body planetary gear set model and (ii) planet load sharing measurements from planetary gear sets having three to six planets. A set of closed-form planet load sharing formulas are derived from the discrete model for gear sets having equally-spaced planets for conditions when all of the planets are loaded. These formulas allow, in an accurate and direct way, calculation of planet loads as a function of position errors associated with each planet.
Abnormal processing of temporal fine structure in speech for frequencies where absolute thresholds are normal
Authors: Lorenzi Christian , Debruille Louis , Garnier Stéphane , Fleuriot Pierre , Moore Brian C. J.
Published: January 2009

The identification of nonsense syllables that were lowpass filtered at 1.5kHz was compared for subjects with normal hearing and subjects with mild-to-severe hearing loss at high frequencies but with normal or near-normal hearing at low frequencies. Absolute thresholds were mostly within the normal range (<20dB hearing level) for both groups for frequencies below 1.5kHz. Performance was assessed with intact speech, speech that had been processed to preserve only temporal envelope cues in a few frequency bands (E speech), and speech that had been processed to remove envelope cues as far as possible while preserving temporal fine structure cues, again in a few frequency bands (TFS speech). For the intact speech and E speech, the hearing-impaired subjects performed slightly more poorly than the normal-hearing subjects, but this effect was significant only for the intact speech. For the TFS speech, the hearing-impaired subjects performed significantly more poorly than the normal-hearing subjects, with 12 out of 16 of the former performing at chance. The results indicate that, for people with hearing loss at medium to high frequencies, the processing of the TFS of speech can be degraded for frequencies where absolute thresholds are within the normal range.
Comment on “Measuring power production in the mammalian cochlea” [Curr. Biol. 17, 1340 (2007)]
Authors: Chen Fangyi , Nuttall Alfred L.
Published: January 2009

Recently, a paper by Lakashkin et al. (2007) (“Power amplification in the mammalian cochlea,” Curr. Biol. 17, 1340–1344) was published on how power can be measured in the mammalian cochlea. The general subject is of current widespread interest, so the question of whether the method used by Lakashkin et al. is valid may be of interest to the readers of this journal. Power generation in the cochlea can account for the extraordinary sensitivity of hearing. Lukashkin et al. claimed to provide a direct proof of cochlear power generation. A first-order spring-dashpot system was used to model the organ of Corti. The power flux direction can be derived from the sign of the phase difference between the force and displacement, which can be presented as a “hysteresis plot.” Basilar membrane (BM) vibration near the characteristic frequency (CF) was measured while applying a low-frequency modulation tone together with the CF tone. A force was derived from the modulation profile of the BM CF vibration and when plotted versus the displacement at the modulation frequency, the function had a counterclockwise direction of hysteresis, suggesting power generation. In this letter, we present comments on the analysis in the report: (1) that it is not appropriate to analyze at the modulation frequency to derive the power generation at CF; (2) that the derivation of a force from just the displacement profile is not justified, followed by an alternative interpretation of the experimental data.
Cooperative prey herding by the pelagic dolphin, Stenella longirostris
Authors: Benoit-Bird Kelly J. , Au Whitlow W. L.
Published: January 2009

Sonar techniques were used to quantitatively observe foraging predators and their prey simultaneously in three dimensions. Spinner dolphins foraged at night in highly coordinated groups of 16–28 individuals using strict four-dimensional patterns to increase prey density by up to 200 times. Herding exploited the prey’s own avoidance behavior to achieve food densities not observed otherwise. Pairs of dolphins then took turns feeding within the aggregation that was created. Using a proxy estimate of feeding success, it is estimated that each dolphin working in concert has more access to prey than it would if feeding individually, despite the costs of participating in the group maneuvers, supporting the cooperation hypothesis. Evidence of a prey density threshold for feeding suggests that feedback from the environment may be enough to favor the evolution of cooperation. The remarkable degree of coordination shown by foraging spinner dolphins, the very strict geometry, tight timing, and orderly turn taking, indicates the advantage conferred by this strategy and the constraints placed upon it. The consistent appearance of this behavior suggests that it may be a critical strategy for energy acquisition by spinner dolphins in energy poor featureless environments in the tropical Pacific Ocean.
Monitoring progressive damage in polymer-based composite using nonlinear dynamics and acoustic emission
Authors: Bentahar Mourad , Guerjouma Rachid El
Published: January 2009

In this work quantitative results of applying nonlinear acoustic dynamics to study progressive damage in a polymer-based composite SMC (sheet molding compound) are presented. Via carefully controlled resonant plate experiment, nonlinear slow dynamics (SNLD) response of SMC in terms of relaxation time and frequency shift has been shown to be very sensitive to gradual damage induced using three-point bending tests. Besides, acoustic emission monitoring is used to characterize damage through the elastic energy released by SMC at every damage step. Interesting logarithmlike changes of the SNLD parameters as a function of the acoustic emission cumulated energy are found.
The decision process in forward-masked intensity discrimination: Evidence from molecular analyses
Authors: Oberfeld Daniel
Published: January 2009

In a two-interval forced-choice intensity discrimination task presenting a fixed increment, the level of the forward masker in interval 1 and interval 2 was sampled independently from the same normal distribution on each trial. Mean and standard deviation of the distribution were varied. Correlational analyses of the trial-by-trial data revealed different decision strategies depending on the relation between mean masker level and standard level. If the two levels were identical, listeners tended to select the interval containing the higher-level masker, behaving like an energy detector at the output of a temporal window of integration. For mean masker level higher than the standard level, most listeners showed a negative correlation between the masker level in a given interval and the probability of selecting this interval, indicating a strategy of comparing the masker loudness and the target loudness in each of the two observation intervals, and voting for the interval where the loudness difference was smaller. Implications for models of forward-masked intensity discrimination and differences from decision strategies reported for forward-masked detection tasks [Jesteadt et al., (2005). “Effect of variability in level on forward masking and on increment detection,” J. Acoust. Soc. Am. 118, 325–337] are discussed.
A broadband fast multipole accelerated boundary element method for the three dimensional Helmholtz equation
Authors: Gumerov Nail A. , Duraiswami Ramani
Published: January 2009

The development of a fast multipole method (FMM) accelerated iterative solution of the boundary element method (BEM) for the Helmholtz equations in three dimensions is described. The FMM for the Helmholtz equation is significantly different for problems with low and high kD (where k is the wavenumber and D the domain size), and for large problems the method must be switched between levels of the hierarchy. The BEM requires several approximate computations (numerical quadrature, approximations of the boundary shapes using elements), and these errors must be balanced against approximations introduced by the FMM and the convergence criterion for iterative solution. These different errors must all be chosen in a way that, on the one hand, excess work is not done and, on the other, that the error achieved by the overall computation is acceptable. Details of translation operators for low and high kD, choice of representations, and BEM quadrature schemes, all consistent with these approximations, are described. A novel preconditioner using a low accuracy FMM accelerated solver as a right preconditioner is also described. Results of the developed solvers for large boundary value problems with 0.0001≲kD≲500 are presented and shown to perform close to theoretical expectations.