bluuebunny/crossref_metadata_2025 huggingface dataset:
Toxoplasmaand reaction time: role of toxoplasmosis in the origin, preservation and geographical distribution of Rh blood group polymorphism
Authors: NOVOTNÁ M. , HAVLÍČEK J. , SMITH A. P. , KOLBEKOVÁ P. , SKALLOVÁ A. , KLOSE J. , GAŠOVÁ Z. , PÍSAČKA M. , SECHOVSKÁ M. , FLEGR J.
Published: August 2008

The RhD protein which is theRHDgene product and a major component of the Rh blood group system carries the strongest blood group immunogen, the D-antigen. This antigen is absent in a significant minority of the human population (RhD-negatives) due toRHDdeletion or alternation. The origin and persistence of this RhD polymorphism is an old evolutionary enigma. Before the advent of modern medicine, the carriers of the rarer allele (e.g. RhD-negative women in the population of RhD-positives or RhD-positive men in the population of RhD-negatives) were at a disadvantage as some of their children (RhD-positive children born to pre-immunized RhD-negative mothers) were at a higher risk of foetal or newborn death or health impairment from haemolytic disease. Therefore, the RhD-polymorphism should be unstable, unless the disadvantage of carriers of the locally less abundant allele is counterbalanced by, for example, higher viability of the heterozygotes. Here we demonstrated for the first time that amongToxoplasma-free subjects the RhD-negative men had faster reaction times than Rh-positive subjects and showed that heterozygous men with both the RhD plus and RhD minus alleles were protected against prolongation of reaction times caused by infection with the common protozoan parasiteToxoplasma gondii. Our results suggest that the balancing selection favouring heterozygotes could explain the origin and stability of the RhD polymorphism. Moreover, an unequal prevalence of toxoplasmosis in different countries could explain pronounced differences in frequencies of RhD-negative phenotype in geographically distinct populations.
PUNISHMENT, INVALIDATION, AND NONVALIDATION: What H. L. A. Hart Did Not Explain
Authors: Stith Richard
Published: August 2008

Elaborating first upon H. L. A. Hart's distinction between imposing duties and imposing disabilities, this article explores the two senses mentioned (but not fully explained) by Hart in which power-holders may be legally disabled. Legal invalidation (nullification) of norms that have been generated by vulnerable power-holders is seen to reduce diversity or pluralism in every normative sphere, from the supranational to the intrafamilial. By contrast, mere legal nonvalidation (noncognizance) of such norms tends to preserve the autonomy of the power-holders that created the norms, thus enhancing legal pluralism. Punishment for creating forbidden norms amounts in principle to an in-between sort of control, less restrictive than completely invalidating them but more restrictive than just not validating them, that is, just ignoring them. Illustrative examples include the European Court of Justice's early use of invalidation to convert an international treaty into a supranational constitution, and the subtle effects of legal nonvalidation of same-sex marriage.
Unterscheidet sich die Struktur des Arbeitsgedächtnisses bei Schulkindern mit und ohne Lernstörung?
Authors: Schuchardt Kirsten , Roick Thorsten , Mähler Claudia , Hasselhorn Marcus
Published: August 2008

Zusammenfassung. 245 Kinder der ersten bis vierten Klassenstufe bearbeiten eine ausführliche Testbatterie zur Erfassung der Funktionstüchtigkeit bei phonologischen, visuell-räumlichen und zentral-exekutiven Arbeitsgedächtnisanforderungen. Etwa die Hälfte dieser Kinder leiden unter einer diagnostizierten Lernstörung (ICD-10). Mit Hilfe statistischer Dimensions- und Strukturanalysen konnte gezeigt werden, dass die der verwendeten Arbeitsgedächtnistestbatterie zugrunde liegende Vorstellung der Struktur von drei vergleichsweise unabhängigen Faktoren des Arbeitsgedächtnisses in gleicher Weise Gültigkeit hat für Kinder mit vs. ohne Lernstörung.
Die künstlerischen Therapien im Zeitalter der Neurowissenschaften
Authors: Jansen-Osmann Petra
Published: August 2008

Zusammenfassung. Diese Arbeit diskutiert den Einfluss der Neurowissenschaften auf die künstlerischen Therapien. Zunächst wird eine sehr kurze Einführung in die psychotherapeutischen Verfahren und ein kurzer Überblick über die künstlerischen Therapien gegeben. Dabei wird die Frage nach der Effektivität diskutiert. In einem weiteren Kapitel wird dann ein Überblick über die relevanten neurowissenschaftlichen Methoden gegeben, die in der Psychologie von großer Bedeutung sind. Insbesondere werden die Methoden der Elektro-Enzephalografie (EEG), der Magnet-Resonanz-Tomografie (MRT), der funktionellen Magnet-Resonanz-Tomographie (fMRT) und der Positronen-Emissions-Tomografie (PET) erklärt. Abschließend werden die Anwendungspotenziale der Neurowissenschaften in den psychotherapeutischen und künstlerischen Therapien erläutert.
Wort für Wort
Authors: Heimes Silke , Seizer Hans-Ulrich , Soyka Michael , Zingg Christina
Published: August 2008

Zusammenfassung. Anliegen: Die heilende Wirkung von Sprache und Schrift, in Form der in Amerika längst etablierten Poesietherapie, kann man sich auch in der deutschen Psychiatrie und Psychotherapie zunutze machen. Methodik: Untersucht wurden 19 Patienten mit Erschöpfungssyndrom und Depressiver Störung, die auf der Grundlage eines integrierten psychiatrisch-psychotherapeutischen Konzeptes stationär behandelt wurden und zweimal wöchentlich an der Poesietherapie teilnahmen. Die Datenerhebung erfolgte anhand spezifisch für die Poesietherapie entworfener Evaluationsbögen und anhand der BfS nach Zerrsen. Ergebnis: Die Teilnehmer konnten in allen Kategorien (Ich-Stärke, Selbstreflexion, Bewusstseinserweiterung, Neuorientierung, Selbstwert) von der Poesietherapie profitieren, zudem verbesserte sich die subjektive Befindlichkeit. Diskussion: Die vorliegende Studie bestätigt die Ergebnisse der amerikanischen Studien. Die in einer amerikanischen Metaanalyse gewonnene Erkenntnis, dass Frauen in höherem Maß von der Poesietherapie profitieren als Männer, ließ sich hingegen nicht nachvollziehen.
Assessment of health related issues in individuals’, couples’, and families’ daily life
Authors: Perrez Meinrad , Reicherts Michael , Hänggi Yves , Horn Andrea B. , Michel Gisela , Schoebi Dominik , Wilhelm Peter
Published: August 2008

Abstract. Most research in health psychology is based on retrospective self reports, which are distorted by recall biases and have low ecological validity. To overcome such limitations we developed computer assisted diary approaches to assess health related behaviours in individuals’, couples’ and families’ daily life. The event- and time-sampling-based instruments serve to assess appraisals of the current situation, feelings of physical discomfort, current emotional states, conflict and emotion regulation in daily life. They have proved sufficient reliability and validity in the context of individual, couple and family research with respect to issues like emotion regulation and health. As examples: Regarding symptom reporting curvilinear pattern of frequencies over the day could be identified by parents and adolescents; or psychological well-being is associated with lower variability in basic affect dimensions. In addition, we report on preventive studies to improve parental skills and enhance their empathic competences towards their baby, and towards their partner.
Behavioural Cardiology at the Department of Psychology, Johannes Gutenberg-University Mainz, Germany
Authors: Schwerdtfeger Andreas , Spaderna Heike , Weidner Gerdi , Krohne Heinz W.
Published: August 2008

Abstract. We provide a short overview of the research in Behavioural Cardiology at the Department of Psychology at the Johannes Gutenberg-University Mainz focussing on two lines of research: Studies of psychosocial variables that might enhance or attenuate cardiovascular risk in healthy individuals and studies of psychosocial variables and health behaviours that might impact the health status of patients listed for heart transplantation. Our studies so far suggest that psychosocial factors like anxiety and repressive coping impact information processing and cardiovascular responses to stress. Moreover, we examine the impact of health-protective resource variables including self-efficacy and physical activity on psychological and physiological functioning in everyday life. Our studies of patients newly listed for heart transplantation document high levels of depression, the relevance of ischaemic aetiology regarding negative emotions and lacking support, and difficulties with smoking cessation and fluid restriction. Future analyses will show if these characteristics independently contribute to adverse pre-transplantation outcomes.
Health action process approach
Authors: Schwarzer Ralf , Lippke Sonia , Ziegelmann Jochen P.
Published: August 2008

Abstract. Health Psychology at the Freie Universität Berlin is devoted to research and teaching in the entire field of health psychology, including stress, coping, social support, self-efficacy, personality, quality of life, and health behavior change. In this article, we briefly describe one theory that represents our line of thinking (the Health Action Process Approach), followed by examples of longitudinal and experimental studies on health behavior change. A major finding is that interventions to improve physical activity, healthy nutrition, and dental hygiene are most effective when matched to three stages of change. Moreover, we address the field of health self-regulation across the life span: We are involved in the consortium Autonomy Despite Multimorbidity in Old Age (AMA), co-investigating the project Health Behaviors and Multiple Illnesses in Old Age (PREFER), and we are the home institution of the project Fostering Lifelong Autonomy and Resources in Europe: Behaviour and Successful Aging (FLARE-BSA).
Interindividual differences in emotion regulation
Authors: Weber Hannelore , Geisler Fay , Kubiak Thomas , Siewert Kerstin
Published: August 2008

Abstract. In this article, we present a short overview of findings from our current research on interindividual differences in emotion regulation and their consequences for health and well-being. In our research that is based on experimental designs, ambulatory assessment methods as well as cross-sectional surveys, we examine interindividual differences in expectancies, strategies and goals that we assume to be associated with adaptive stress and emotion regulation. Among the interindividual differences in goals and strategies, we focus on functional and dysfunctional dispositional anger-related goals and strategies, and the habitual use of humor, ruminative thinking, and eating behavior as strategies of emotion regulation. With regard to health-related expectancies, possible mechanisms linking dispositional optimism with the perception and receipt of social support are a main area of our current research.
Die Bedeutung von Unsicherheitsintoleranz für die Generalisierte Angststörung Modellüberlegungen und Entwicklung einer deutschen Version der Unsicherheitsintoleranz-Skala
Authors: Gerlach Alexander L. , Andor Tanja , Patzelt Julia
Published: August 2008

Zusammenfassung. Theoretischer Hintergrund: In der neueren Literatur wird Unsicherheitsintoleranz (UI) als ein wichtiger Faktor bei der Entstehung und Aufrechterhaltung der Generalisierten Angststörung diskutiert. Die Skala zur Erfassung von UI fehlt bisher in deutscher Sprache. Fragestellung: Welche psychometrischen Eigenschaften weist die deutsche Übersetzung der „Intolerance of Uncertainty Scale” auf? Welche Faktorenstruktur liegt der Skala zugrunde? Kann das Instrument gekürzt werden? Ist die neu gewonnene Faktorenstruktur in einer unabhängigen Stichprobe zu replizieren? Welchen Anteil der Varianz der Sorgenaktivität (PSWQ) kann UI erklären? Wie lässt sich UI mit anderen relevanten Konstrukten in ein Modell der GAS integrieren? Methode: Mit Hilfe einer explorativen Faktorenanalyse wurde an einer studentischen Stichprobe (N = 682) die Faktorenstruktur des deutschen UI Fragebogens gewonnen. Auf Grundlage dieser Faktorenstruktur wurde eine gekürzte Version (UI-18) erstellt. Diese Faktorenstruktur wurde in einer zweiten studentischen Stichprobe (N = 540) konfirmiert. Zur Konstruktvalidierung wurde ein Regressionsmodell zur Vorhersage von Sorgenaktivität gerechnet. Ergebnisse: Der neu gewonnene Fragebogen UI-18 weist drei replizierbare Faktoren auf („Eingeschränkte Handlungsfähigkeit bei UI”, „Belastung durch UI” und „Vigilanz bei UI”). Die UI Skalen Belastung und Vigilanz, vier Skalen des Metakognitionsfragebogen und Geschlecht sagen bedeutsam Sorgenaktivität voraus. Schlussfolgerungen: Unsicherheitsintoleranz kann reliabel gemessen werden. Vor dem Hintergrund unserer Ergebnisse wird ein Modell der GAS vorgestellt, das Unsicherheitsintoleranz, Metakognitionen bezüglich des Sorgens sowie die Vermeidungstheorie des Sorgens integriert.
The Relationship Between Goal Orientation, Social Comparison Responses, Self-Efficacy, and Performance
Authors: Carmona Carmen , Buunk Abraham P. , Dijkstra Arie , Peiró José M.
Published: August 2008

The present study examined whether social comparison responses (identification and contrast in social comparison) mediated the relationship between goal orientation (promotion and prevention) and self-efficacy, and whether self-efficacy was subsequently related with a better performance. As expected, the results showed that promotion-oriented individuals – who are focused on achieving success – had higher self-efficacy than prevention-oriented individuals – who are focused on avoiding failure. Only one of the social comparison responses had a mediating role. That is, the tendency to contrast oneself with others who were doing better mediated the relationship between a prevention goal orientation and self-efficacy. In addition, self-efficacy was related to a better performance.
Reinitiation or termination of fluid‐driven fractures at frictional bedding interfaces
Authors: Zhang Xi , Jeffrey Robert G.
Published: August 2008

A two‐dimensional numerical model for coupled elastic deformation and fluid flow has been developed to examine reinitiation or termination of a vertical fluid‐driven fracture in bedded rocks. The rocks on both sides of the bedding interface are assumed to be impermeable, and a Newtonian fluid, whose viscous dissipation cannot be neglected, is injected at a constant rate. Crack nucleation on the frictional interface is controlled by a tensile stress criterion. A fracture approaching the interface or terminating on it can generate a large bed‐parallel tensile stress in the uncracked layer in excess of the local tensile strength to initiate a new fracture. The propagation of the nucleated fracture is assisted by interface sliding and pressurized fluid. The bedding interface can provide a conductive channel to connect the parent and the new fractures. Fluid partitioning among fracture branches depends on local stress states and triggers their competition to become the main fracture. The three types of fracture patterns generated numerically by the model are crosscutting through, terminating at, and offsetting at the interface. A large modulus or toughness contrast across the interface can lead to containment of the hydraulic fracture on the interface. For offsetting fractures, the presence of the bedding plane can reduce fracture permeability, and any associated high‐stress barrier acts to slow or arrest further fluid‐driven fracture growth. Propagating the new fracture results in high excess pressure, consistent with measured abnormal pressure in commercial fracture treatments. The predicted offset distances are on the order of centimeters, and their continued growth is perpendicular to the bedding contacts.
Lava dome growth and mass wasting measured by a time series of ground‐based radar and seismicity observations
Authors: Wadge G. , Macfarlane D. G. , Odbert H. M. , James M. R. , Hole J. K. , Ryan G. , Bass V. , De Angelis S. , Pinkerton H. , Robertson D. A. , Loughlin S. C.
Published: August 2008

Exogenous growth of Peléean lava domes involves the addition of lava from a central summit vent and mass wasting on the flanks as rockfalls and pyroclastic flows. These processes were investigated at the Soufrière Hills Volcano, Montserrat, between 30 March and 10 April 2006, using a ground‐based imaging millimeter‐wave radar, AVTIS, to measure the shape of the dome and talus surface and rockfall seismicity combined with camera observations to infer pyroclastic flow deposit volumes. The topographic evolution of the lava dome was recorded in a time series of radar range and intensity measurements from a distance of 6 km, recording a southeastward shift in the locus of talus deposition with time, and an average height increase for the talus surface of about 2 m a day. The AVTIS measurements show an acceleration in lava extrusion rate on 5 April, with a 2‐day lag in the equivalent change in the rockfall seismicity record. The dense rock equivalent volumetric budget of lava added and dispersed, including the respective proportions of the total for each component, was calculated using: (1) AVTIS range and intensity measurements of the change in summit lava (∼1.5 × 106 m3, 22%), (2) AVTIS range measurements to measure the talus growth (∼3.9 × 106 m3, 57%), and (3) rockfall seismicity to measure the pyroclastic flow deposit volumes (∼1.4 × 106 m3, 21%), which gives an overall dense rock equivalent extrusion rate of about 7 m3·s−1. These figures demonstrate how efficient nonexplosive lava dome growth can be in generating large volumes of primary clastic deposits, a process that, by reducing the proportion of erupted lava stored in the summit region, will reduce the likelihood of large hazardous pyroclastic flows.
Seasonal variations of the Yellow River plume in the Bohai Sea: A model study
Authors: Wang Qiang , Guo Xinyu , Takeoka Hidetaka
Published: August 2008

We investigated the behavior of the Yellow River plume in the Bohai Sea through a year and its controlling mechanisms using a numerical model driven by monthly averaged wind stress, heat flux, and river discharge. The model produced a clear seasonal behavior of the Yellow River plume. In summer, the Yellow River plume extends northeastward into the central Bohai Sea; in autumn, it turns southward and flows into Laizhou Bay along the coast; in winter, most of the diluted water is found around southeastern corner of Laizhou Bay; and in spring, a low‐salinity area appears in southwest Laizhou Bay. With the same model, several well‐designed numerical experiments were performed to investigate the effect on the behavior of the Yellow River plume of tidal current, river discharge, wind stress, and thermal stratification. The tidal currents promote the offshore spread of diluted water, while the tide‐induced residual currents prevent the plume from extending further downstream (in the direction of Kelvin wave propagation). Wind stresses lead to pronounced changes in the path and shape of the plume. In autumn and winter, northwesterly or northerly winds drive the buoyant water into Laizhou Bay along the coast. In summer, the combination of southeasterly winds and thermal stratification drives the plume extend northeastward into the central Bohai Sea. By changing only the magnitude of wind stress or river discharge in the experiments, we examined the sensitivity of summertime plume to the magnitude of wind stress and river discharge.
Total lightning activity as an indicator of updraft characteristics
Authors: Deierling Wiebke , Petersen Walter A.
Published: August 2008

This study investigates the relationship of total lightning activity and updraft characteristics, such as updraft volume and maximum updraft speed, for a number of storms of different types occurring in the High Plains and in Northern Alabama. Ground‐based Doppler and dual polarimetric radar observations were used to compute updraft characteristics. Also, ground‐based total lightning data were available at both locations. Results show that time series of updraft volume in the charging zone (at temperatures colder than −5°C) with vertical velocities greater than either 5 or 10 m s−1 have clear relationships with total lightning activity (r = 0.93). Furthermore, these relationships between updraft volume and lightning activity for the storm types of the two climate regimes tend to converge when considering only the subfreezing layers of the clouds. Neither the maximum nor the mean updraft speed correlate as well with total lightning activity (r = <0.8) as updraft volume. Through expanded study designed to explore further regime variability (or lack thereof) of updraft volume‐lightning flash rate relationships, better or refined parameterizations for the numerical forecasting of lightning and/or detection and prediction of storm intensity could be realized.
Mapping outlet points used for watershed delineation onto DEM‐derived stream networks
Authors: Lindsay John B. , Rothwell James J. , Davies Helen
Published: August 2008

Outlet point positions taken from hydrometric stations commonly do not coincide with stream locations extracted from digital elevation models (DEMs). This is a serious problem for accurate watershed delineation of data sets containing numerous outlets, which is critical in regional‐scale studies that relate catchment characteristics to basin responses. The advanced outlet repositioning approach (AORA), presented here, replicates the processes involved in manual outlet placement while reducing inefficiency and potential for blunders. The technique uses water body names to identify locations for outlet repositioning that are consistent with nearby outlets. The AORA performance was compared against two existing automated techniques using 993 stations in seven basins in northwest England. The AORA had the fewest repositioning errors in each basin and nearly halved the overall number of errors in the data set, compared with the second‐best method. This work highlights the potential errors that may be present in studies that have employed existing automated watershed mapping methods.
Persistent global proton aurora caused by high solar wind dynamic pressure
Authors: Laundal K. M. , Østgaard N.
Published: August 2008

Global images of the proton aurora taken with the SI‐12 camera onboard the IMAGE satellite reveal a very direct relationship between the solar wind dynamic pressure and the intensity of the global proton aurora. We show that an increase in dynamic pressure leads to an immediate and persistent increase in proton precipitation, also when the increase is slow. When the dynamic pressure decreases, the proton aurora diminishes. Five events during geomagnetic quiet times, with mostly northward IMF, have been selected in order to characterize the proton aurora caused exclusively by high dynamic pressure and establish important criteria that the dynamic pressure‐induced precipitation mechanism(s) must satisfy. We also present measurements during southward IMF and show that the combined effect of high solar wind dynamic pressure and southward IMF produces intense global proton aurora. Some of the characteristics are: (1) The aurora is global, with peak intensities at midnight and flanks. (2) A dawn/dusk asymmetry shows that the precipitation originates from magnetospheric protons that have undergone gradient/curvature drift. (3) The time delay between ground magnetic signatures of a change in the solar wind dynamic pressure and a change in global proton aurora is short (−2 minutes). Our observations indicate that the precipitation mechanism(s) behind the proton aurora during high dynamic pressure is directly connected to the compression of the magnetosphere, both at the flanks and nightside.
Asymmetry parameters in the lower troposphere derived from aircraft measurements of aerosol scattering coefficients over tropical India
Authors: Ramachandran S. , Rajesh T. A.
Published: August 2008

Aerosol scattering coefficients (total βsca and backscatter βbacksca) are measured on board an aircraft using an integrating nephelometer at 450, 550, and 700 nm in the 0 to 3000‐m region over four locations in India in an air campaign held during March–May 2006. βsca is a factor of two higher in the east (Bhubaneshwar, Chennai) than in the west (Trivandrum, Goa). βsca is about 5–10 × 10−5 m−1 over Bhubaneshwar and Chennai. βbacksca is about an order of magnitude lower than βsca. Seven‐day air back trajectory analysis indicate that air masses originating from arid/semiraid regions, continents, and marine regions are found to influence the aerosol characteristics, in addition to local urban sources. No elevated aerosol layers are seen during the campaign. b, the aerosol backscatter fraction, is greater than 0.13 in the lower troposphere. The columnar mean Ångström exponent (α) is >1.75. Asymmetry parameter g profiles are derived for the first time over India in the lower troposphere, using the relation between b and g. 550‐nm g corresponding to 30% RH is in the 0.3–0.6 range over India. Higher b, higher α, and lower g values over these locations suggest the dominance of submicron aerosols during the campaign. Scattering aerosols corrected to 30% RH in the 0 to 3000‐m altitude region contribute about 20–35% to MODIS aerosol optical depths (AODs). The variation in the contribution of scattering aerosols to AODs highlights the spatial and vertical differences in aerosol properties.
Model complexity control for hydrologic prediction
Authors: Schoups G. , van de Giesen N. C. , Savenije H. H. G.
Published: August 2008

A common concern in hydrologic modeling is overparameterization of complex models given limited and noisy data. This leads to problems of parameter nonuniqueness and equifinality, which may negatively affect prediction uncertainties. A systematic way of controlling model complexity is therefore needed. We compare three model complexity control methods for hydrologic prediction, namely, cross validation (CV), Akaike's information criterion (AIC), and structural risk minimization (SRM). Results show that simulation of water flow using non‐physically‐based models (polynomials in this case) leads to increasingly better calibration fits as the model complexity (polynomial order) increases. However, prediction uncertainty worsens for complex non‐physically‐based models because of overfitting of noisy data. Incorporation of physically based constraints into the model (e.g., storage‐discharge relationship) effectively bounds prediction uncertainty, even as the number of parameters increases. The conclusion is that overparameterization and equifinality do not lead to a continued increase in prediction uncertainty, as long as models are constrained by such physical principles. Complexity control of hydrologic models reduces parameter equifinality and identifies the simplest model that adequately explains the data, thereby providing a means of hydrologic generalization and classification. SRM is a promising technique for this purpose, as it (1) provides analytic upper bounds on prediction uncertainty, hence avoiding the computational burden of CV, and (2) extends the applicability of classic methods such as AIC to finite data. The main hurdle in applying SRM is the need for an a priori estimation of the complexity of the hydrologic model, as measured by its Vapnik‐Chernovenkis (VC) dimension. Further research is needed in this area.
Abrogation of the resistance of choline-induced Pseudomonas aeruginosa virulence to sub-MIC erythromycin by ethanol
Authors: Katri Nava , Garber Nachman Chaim , Kilfin Gillar , Gilboa-Garber Nechama
Published: August 2008

Despite Pseudomonas aeruginosa antibiotic resistance, erythromycin (ERM, a macrolide) at subinhibitory concentration (sub-MIC) reduces its pathogenicity. We assessed ERM effects on P. aeruginosa in cultures containing choline (Ch) without and with 1% ethanol (Et) addition. Ch, as an osmoprotectant, increases the following virulence factors (VIFs): lectins (haemagglutination); proteases (casein and elastin lysis); haemolytic phospholipase C (PLC-H; haemolysis); pyocyanin (pigment o.d.) and autoinducers (violacein bioassay). Ethanol also increases lectins, proteases, pyocyanin, autoinducers and rhamnolipid (RHAL; haemolysis) formation, but reduces Ch-induced PLC and protease (elastase) activities. ERM has been shown to totally suppress the Et-induced VIFs, whereas partially reducing the Ch-induced ones. Unexpectedly, ERM combination with 1% Et dramatically annuls the Ch-induced factors. Et contribution might be attributed to its effect on cell membrane, displaying synergism with ERM, whereas antagonizing Ch osmoprotective potential and shifting gene expression. This information is worth further molecular investigation and clinical consideration for skin infection therapy.
Increases in Weight and Body Size Increase the Odds for Hypertension During 7 Years of Follow‐up
Authors: Williams Paul T.
Published: August 2008

Changes in BMI and body size were compared to incident hypertension in 24,550 men and 10,111 women followed prospectively as part of the National Runners' Health Study to test whether long‐term weight change affects hypertension risk. Incident hypertensions were reported by 2,143 men and 430 women during (mean ± s.d.) 7.8 ± 1.8 and 7.5 ± 2.0 years of follow‐up, respectively. Despite being active, men's and women's BMI increased 1.15 ± 1.70 and 0.95 ± 1.89 kg/m2, respectively, and their waist circumferences increased 2.97 ± 5.02 and 3.29 ± 6.67 cm, respectively. Compared to those whose BMI declined, those who gained ≥2.4 kg/m2 had an odds ratio (95% confidence interval) of 1.68 (1.45, 1.94) for becoming hypertensive if male and 1.42 (1.05, 1.92) if female. Men whose waist circumference increased ≥6 cm had an odds ratio of 1.22 (1.01, 1.47) for becoming hypertensive compared to those whose waists decreased. In both sexes, the odds for hypertension were significantly related to BMI at follow‐up when adjusted for baseline BMI, but generally not to baseline BMI when adjusted for follow‐up BMI. In the subset whose weights remained relatively unchanged during follow‐up (±0.4 kg/m2), each kg/m2 increment in BMI was associated with an odds ratio for becoming hypertensive of 1.19 (1.14, 1.24) in men and 1.11 (1.02, 1.20) in women. Thus, even among lean, physically active individuals: (i) weight gain increases hypertension risk; (ii) higher body weight increases the hypertension risk in a dose‐dependent manner in the absence of any weight change; and (iii) there is no advantage carried forward to having been previously lean.
Disruption of a mitochondrial RNA-binding protein gene results in decreased cytochrome b expression and a marked reduction in ubiquinol–cytochrome c reductase activity in mouse heart mitochondria
Authors: Xu Fenghao , Ackerley Cameron , Maj Mary C. , Addis Jane B. L. , Levandovskiy Valeriy , Lee Jisoo , MacKay Nevena , Cameron Jessie M. , Robinson Brian H.
Published: August 2008

Mice homozygous for a defect in the PTCD2 (pentatricopeptide repeat domain protein 2) gene were generated in order to study the role of this protein in mitochondrial RNA metabolism. These mice displayed specific but variable reduction of ubiquinol–cytochrome c reductase complex activity in mitochondria of heart, liver and skeletal muscle due to a decrease in the expression of mitochondrial DNA-encoded cytochrome b, the catalytic core of the complex. This reduction in mitochondrial function has a profound effect on the myocardium, with replacement of ventricular cardiomyocytes by fibro-fatty tissue. Northern blotting showed a reduction in the mRNA for the mitochondrial DNA encoded proteins cytochrome b (cytb) and ND5 (NADH dehydrogenase subunit 5) and an elevation in a combined pre-processed ND5-CYTB transcript. This suggests that the PTCD2 protein is involved in processing RNA transcripts involving cytochrome b derived from mitochondrial DNA. This defines the site for PTCD2 action in mammalian mitochondria and suggests a possible role for dysfunction of this protein in the aetiology of heart failure.
A simple patchy colloid model for the phase behavior of lysozyme dispersions
Authors: Gögelein Christoph , Nägele Gerhard , Tuinier Remco , Gibaud Thomas , Stradner Anna , Schurtenberger Peter
Published: August 2008

We propose a minimal model for spherical proteins with aeolotopic pair interactions to describe the equilibrium phase behavior of lysozyme. The repulsive screened Coulomb interactions between the particles are taken into account assuming that the net charges are smeared out homogeneously over the spherical protein surfaces. We incorporate attractive surface patches, with the interactions between patches on different spheres modeled by an attractive Yukawa potential. The parameters entering the attractive Yukawa potential part are determined using information on the experimentally accessed gas-liquid-like critical point. The Helmholtz free energy of the fluid and solid phases is calculated using second-order thermodynamic perturbation theory. Our predictions for the solubility curve are in fair agreement with experimental data. In addition, we present new experimental data for the gas-liquid coexistence curves at various salt concentrations and compare these with our model calculations. In agreement with earlier findings, we observe that the strength and the range of the attractive potential part only weakly depend on the salt content.
Reversible geminate recombination of hydrogen-bonded water molecule pair
Authors: Markovitch Omer , Agmon Noam
Published: August 2008

The (history independent) autocorrelation function for a hydrogen-bonded water molecule pair, calculated from classical molecular dynamics trajectories of liquid water, exhibits a t−3/2 asymptotic tail. Its whole time dependence agrees quantitatively with the solution for reversible diffusion-influenced geminate recombination derived by Agmon and Weiss [J. Chem. Phys. 91, 6937 (1989)]. Agreement with diffusion theory is independent of the precise definition of the bound state. Given the water self-diffusion constant, this theory enables us to determine the dissociation and bimolecular recombination rate parameters for a water dimer. (The theory is indispensable for obtaining the bimolecular rate coefficient.) Interestingly, the activation energies obtained from the temperature dependence of these rate coefficients are similar, rather than differing by the hydrogen-bond (HB) strength. This suggests that recombination requires displacing another water molecule, which meanwhile occupied the binding site. Because these activation energies are about twice the HB strength, cleavage of two HBs may be required to allow pair separation. The autocorrelation function without the HB angular restriction yields a recombination rate coefficient that is larger than that for rebinding to all four tetrahedral water sites (with angular restrictions), suggesting the additional participation of interstitial sites. Following dissociation, the probability of the pair to be unbound but within the reaction sphere rises more slowly than expected, possibly because binding to the interstitial sites delays pair separation. An extended diffusion model, which includes an additional binding site, can account for this behavior.
Measurement of the thermal conductivity of nanofluids by the multicurrent hot-wire method
Authors: Peñas José R. Vázquez , Ortiz de Zárate José M. , Khayet Mohamed
Published: August 2008

We present experimental results of the thermal conductivity of several nanofluids prepared by dispersing nanoparticles of SiO2 and CuO in water and ethylene glycol at various concentrations up to ≈5% in mass fraction. The measurements have been performed by the multicurrent hot-wire technique. Good agreement, within 2%, is found in recommended and published thermal conductivities of the pure fluids. Our experimental technique allows a very accurate determination of the enhancement in the thermal conductivity of the fluids due to the presence of dispersed nanoparticles. Measured enhancements compare well with some of the values published so far in the literature. We have compared our results with simple theoretical models that predict the thermal conductivity of solid suspensions and found that in some cases observed enhancements are several times larger than the predicted ones.
Symplectic and multisymplectic Lobatto methods for the “good” Boussinesq equation
Authors: Aydın A. , Karasözen B.
Published: August 2008

In this paper, we construct second order symplectic and multisymplectic integrators for the “good” Boussineq equation using the two-stage Lobatto IIIA-IIIB partitioned Runge–Kutta method, which yield an explicit scheme and is equivalent to the classical central difference approximation to the second order spatial derivative. Numerical dispersion properties and the stability of both integrators are investigated. Numerical results for different solitary wave solutions confirm the excellent long time behavior of symplectic and multisymplectic integrators by preserving local and global energy and momentum.
Low temperature Raman spectra of hydrogen in simple and binary clathrate hydrates
Authors: Giannasi Alessandra , Celli Milva , Ulivi Lorenzo , Zoppi Marco
Published: August 2008

The Raman spectrum of hydrogen clathrate hydrates has been measured, as a function of temperature, down to 20 K. Rotational bands of H2 and HD, trapped into the small cages of simple (H2O–H2) and binary (H2O–THF–H2) hydrates, have been analyzed and the fivefold degeneracy of the molecular J=2 rotational level has been discussed in the light of the available theoretical calculations. The vibrational frequencies of H2 molecules encapsulated in the large cages of simple hydrates turn out to be well separated from those pertaining to the small cages. Comparison with the equivalent D2 spectra allowed us to assign the large cavity vibrational frequencies to three couples of Q1(1)−Q1(0)H2 vibrational modes. Populations of ortho and para species have been measured as a function of time from rotational spectra and the rate of ortho-para conversion has been estimated for both simple and binary hydrates. We suggest, using the H2 vibrational spectra, a model to analyze the cage population in simple hydrates.
Plasmonic properties of a metallic torus
Authors: Dutta Chizuko M. , Ali Tamer A. , Brandl Daniel W. , Park Tae-Ho , Nordlander Peter
Published: August 2008

Using the plasmon hybridization method, we investigate the optical properties of metallic tori of different shapes and for different polarizations. The plasmon energies are found to be strongly dependent on polarization and on the aspect ratio of the torus, which we define as the ratio of the radii of the two circles that define the structure. For incident light polarized in the plane of the torus, the optical spectrum is characterized by two features, a long wavelength highly tunable dipolar plasmon resonance, and a short wavelength mode corresponding to excitation of several higher order torus modes. For aspect ratios smaller than 0.8, we find that the energy of the tunable dipolar torus mode can be described analytically as an infinite cylinder plasmon of a wavelength equal to the length of the tube. For perpendicular polarization, the spectrum exhibits a single feature made up of several closely spaced higher order torus modes which are only weakly dependent on the aspect ratio. The calculated optical properties are found to be in excellent agreement with results from numerical finite difference time domain calculations and with results from other groups.
Using thin film transistors to quantify carrier transport properties of amorphous organic semiconductors
Authors: Cheung C. H. , Tsung K. K. , Kwok K. C. , So S. K.
Published: August 2008

The hole transport properties of two phenylamine-based compounds were evaluated by thin film transistor (TFT) measurement and time-of-flight (TOF) technique. The compounds were N,N′-diphenyl-N,N′-bis(1-naphthyl) (1,1′biphenyl)-4,4′diamine (NPB) and 4,4′,4″-tris[n-(2-naphthyl)-n-phenyl-amino] triphenylamine (2TNATA). With tungsten oxide/gold as the charge injecting electrode, the field effect mobility of NPB was found to be 2.4×10−5cm2∕Vs at room temperature, which was about one order of magnitude smaller than that obtained from independent TOF experiments (3×10−4cm2∕Vs). Similar observations were found for 2TNATA. Temperature dependent measurements were carried out to study the energetic disorder of the materials. It was found that the energetic disorder was increased in the neighborhood of a gate dielectric layer.
Effect of discrete coherent structures on plasma-wall interactions in the scrape-off-layer
Authors: D’Ippolito D. A. , Myra J. R.
Published: August 2008

The effect of discrete plasma transport by coherent structures on plasma-wall interactions in the scrape-off-layer (SOL) is illustrated by a simple model problem. A one-dimensional ballistic model is studied in which a periodic train of plasma blobs creates a series of discrete pulses of neutral atoms by sputtering of a high-Z wall. Collisions between the neutral pulses and blobs lead to ionization of the high-Z atoms, convective transport back to the wall, and subsequent self-sputtering. An analytic condition for high-Z impurity avalanche is calculated and evaluated taking into account the effect of the temperature nonlinearity of the ionization rate. It is shown that the discreteness of the blob particle and energy transport leads to quite different results than a steady-state fluid model with the same average density and temperature. Similar effects are expected in fully intermittent transport due to turbulence or edge localized modes in the SOL of tokamaks. The model calculations also illustrate a potentially important interaction between high-power radio frequency antennas and high-Z walls.
Improving selective thermal emission properties of three-dimensional macroporous silicon through porosity tuning
Authors: Garín M. , Trifonov T. , Rodríguez A. , Alcubilla R. , Marquier F. , Arnold C. , Greffet J.-J.
Published: August 2008

We present a theoretical and experimental study on the effect of progressive porosity increase, through multiple oxidation/oxide removal steps, upon the optical characteristics in three-dimensional macroporous silicon. It is shown that, by increasing porosity, optical features can be pushed toward higher frequencies. Optimum porosities exist where normal or omnidirectional total reflection bandwidths are maximized, doubling the initial values. Results are confirmed experimentally through angle-resolved reflectance and thermal emission measurements.
Stamped microbattery electrodes based on self-assembled M13 viruses
Authors: Nam Ki Tae , Wartena Ryan , Yoo Pil J. , Liau Forrest W. , Lee Yun Jung , Chiang Yet-Ming , Hammond Paula T. , Belcher Angela M.
Published: August 2008

The fabrication and spatial positioning of electrodes are becoming central issues in battery technology because of emerging needs for small scale power sources, including those embedded in flexible substrates and textiles. More generally, novel electrode positioning methods could enable the use of nanostructured electrodes and multidimensional architectures in new battery designs having improved electrochemical performance. Here, we demonstrate the synergistic use of biological and nonbiological assembly methods for fabricating and positioning small battery components that may enable high performance microbatteries with complex architectures. A self-assembled layer of virus-templated cobalt oxide nanowires serving as the active anode material in the battery anode was formed on top of microscale islands of polyelectrolyte multilayers serving as the battery electrolyte, and this assembly was stamped onto platinum microband current collectors. The resulting electrode arrays exhibit full electrochemical functionality. This versatile approach for fabricating and positioning electrodes may provide greater flexibility for implementing advanced battery designs such as those with interdigitated microelectrodes or 3D architectures.
Crystal structure of a self-assembling lipopeptide detergent at 1.20 Å
Authors: Ho Dona N. , Pomroy Neil C. , Cuesta-Seijo José A. , Privé Gilbert G.
Published: August 2008

Lipopeptide detergents (LPDs) are a new class of amphiphile designed specifically for the structural study of integral membrane proteins. The LPD monomer consists of a 25-residue peptide with fatty acyl chains linked to side chains located at positions 2 and 24 of the peptide. LPDs are designed to form α-helices that self-assemble into cylindrical micelles, providing a more natural interior acyl chain packing environment relative to traditional detergents. We have determined the crystal structure of LPD-12, an LPD coupled to two dodecanoic acids, to a resolution of 1.20 Å. The LPD-12 monomers adopt the target conformation and associate into cylindrical octamers as expected. Pairs of helices are strongly associated as Alacoil-type antiparallel dimers, and four of these dimers interact through much looser contacts into assemblies with approximate D
2
symmetry. The aligned helices form a cylindrical shell with a hydrophilic exterior that protects an interior hydrophobic cavity containing the 16 LPD acyl chains. Over 90% of the methylene/methyl groups from the acylated side chains are visible in the micelle interiors, and ≈90% of these adopt trans dihedral angle conformations. Dodecylmaltoside (DDM) was required for the crystallization of LPD-12, and we find 10–24 ordered DDM molecules associated with each LPD assembly, resulting in an overall micelle molecular weight of ≈30 kDa. The structures confirm the major design objectives of the LPD framework, and reveal unexpected features that will be helpful in the engineering additional versions of lipopeptide amphiphiles.
Chemical reaction dynamics
Authors: Crim F. Fleming
Published: August 2008

Understanding the motions of the constituent atoms in reacting molecules lies at the heart of chemistry and is the central focus of chemical reaction dynamics. The most detailed questions one can ask are about the evolution of molecules prepared in a single quantum state to products in individual states, and both calculations and experiments are providing such detailed understanding of increasingly complex systems. A central goal of these studies is uncovering the essential details of chemical change by removing the averaging over the initial conditions that occurs in many cases. Such information provides an exquisite test of theory and helps paint pictures of complicated chemical transformations. The goal of this Special Feature is to provide a snapshot of a portion of the field of chemical reaction dynamics. Much of the work presented here emphasizes a close interplay of experiment and theory in ways that sharpen the conclusions of both and animate future studies. The articles do not completely cover the rich field of chemical reaction dynamics but rather provide a glimpse of some of the emerging insights.