bluuebunny/crossref_metadata_2025 huggingface dataset:
Ergonomic Evaluation of the Ambulance Interior to Reduce Paramedic Discomfort and Posture Stress
Authors: Gilad Issachar , Byran Eyal
Published: November 2007

Objective: This study aims to evaluate safety and accessibility of an advanced life support (ALS) ambulance interior. Background: The standard ambulance's interior design is unsatisfactory based on perceived discomfort and postures that constrain paramedics and medical staff, resulting in unsafe treatment of patients, mainly when being transported. Methods: Two procedures were used to evaluate performance during a wide range of rescue tasks: a survey, based on questionnaires, interviews, and observation of paramedics performing routine tasks; and upper body and back posture analysis, based on postural considerations. Results: Findings revealed that 74% of the paramedics stated that the location of the paramedic's seat is inefficient while they perform clinical procedures; 94% found the bench uncomfortable; 77% felt that the vertical distance between the bench and the stretcher is too far; and 86% needed to steady themselves when the vehicle was moving. Posture analysis showed that paramedics undergo several nonneutral back postures, including twisted back (>20°) and sitting with back flexion between 20° and 45°. Conclusion: Because the interior of the ALS ambulance was found to be unsatisfactory both to paramedics and patients, alternative design issues are proposed. Application: The suggested practical layout contains four main modifications: (a) replacing the bench with two adjustable paramedic seats, (b) redesigning the medical cabinet for easy access, (c) adding an adjustable folding seat opposite the two new seats, and (d) adding a swiveling base and lifting apparatus that will accommodate the stretcher and enable better accessibility to patients by the paramedic personnel.
Thermal Comfort and Sensation in Men Wearing a Cooling System Controlled by Skin Temperature
Authors: Vernieuw Carrie R. , Stephenson Lou A. , Kolka Margaret A.
Published: November 2007

Objective: The study was done to determine whether thermal comfort (TC), thermal sensation (TS), and subjective factors gauging environmental stress were negatively affected with different cooling methods in men exercising in chemical protective clothing. Background: Previous studies have reported that intermittent regional cooling improved the efficacy of cooling as compared with constant cooling (CC), but no studies have addressed whether there is any improvement in thermal comfort. Methods: Eight male volunteers exercised at moderate work intensity (425 W) in three microclimate cooling tests. The circulating fluid in the cooling garment was provided during exercise to the head (6% body surface area [BSA]), torso (22% BSA), and thighs (44% BSA) and manipulated under three methods: (a) CC, (b) pulsed cooling (PC), and (c) PC activated by mean skin temperature (Tsk) control (PCskin). TC and TS ratings were recorded every 20 min during the 80-min test. Results: TC and TS ratings were not different for PCskin and CC; thus the participants perceived PCskin as being similar to CC. TS was significantly warmer with PC than with PCskin and CC ( p < .001). In PCskin, Tsk was significantly higher than in PC and CC ( p < .001), and PC skin was rated as being not as warm as PC according to TS. Conclusion: This indicates that the PC skin method was perceived as being as cool as CC and cooler than PC. Application: These findings indicate that the PCskin cooling method is an acceptable alternative to CC and PC based on human perceptions.
Effects of Speech- and Text-Based Interaction Modes in Natural Language Human-Computer Dialogue
Authors: Le Bigot Ludovic , Rouet Jean-François , Jamet Eric
Published: November 2007

Objective: This study examined the effects of user production (speaking and typing) and user reception (listening and reading) modes on natural language human-computer dialogue. Background: Text-based dialogue is often more efficient than speech-based dialogue, but the latter is more dynamic and more suitable for mobile environments and hands-busy situations. The respective contributions of user production and reception modes have not previously been assessed. Method: Eighteen participants performed several information search tasks using a natural language information system in four experimental conditions: phone (speaking and listening), Web (typing and reading), and mixed (speaking and reading or typing and listening). Results: Mental workload was greater and participants' repetitions of commands were more frequent when speech (speaking or listening) was used for both the user production and reception modes rather than text (typing or reading). Completion times were longer for listening than for reading. Satisfaction was lower, utterances were longer, and the interaction error rate was higher for speaking than typing. Conclusion: The production and reception modes both contribute to dialogue and mental workload. They have distinct contributions to performance, satisfaction, and the form of the discourse. Application: The most efficient configuration for interacting in natural language would appear to be speech for production and system prompts in text, as this combination decreases the time on task while improving dialogue involvement.
The Search for Complex Problem-Solving Strategies in the Presence of Stressors
Authors: Van Hiel Alain , Mervielde Ivan
Published: November 2007

Objective: The present research tests the effects of time pressure and noise on openmindedness to discover new problem-solving strategies. Background: We are primarily interested in transfer of skill from one phase to the next. More specifically, this study investigates whether the presence of stressors makes participants adhere to the sustained use of complex rules. Method: Participants learned to apply a complex rule in the first phase of a category learning task. In the second phase, this rule became dysfunctional and participants had to search for a new categorization rule in order to assign the stimuli to the correct classes. Two experiments were set up to investigate this issue. Results: Participants were found to have difficulty discovering a complex Phase 2 rule in the presence of stressors, whereas the discovery of a simple rule was not hindered by the presence of stressors. Conclusion: In the discussion, it is argued that the present results are compatible with previous research on stressors showing that time pressure and noise induce the application of simple strategies. The innovative finding here is that this simplification also occurs in individuals who are accustomed to using complex solutions. Application: The implications of the present results for emergency response training are elaborated upon.
Binocular Rivalry and Head-Worn Displays
Authors: Patterson Robert , Winterbottom Marc , Pierce Byron , Fox Robert
Published: November 2007

Objective: We provide a review and analysis of much of the published literature on binocular rivalry that is relevant to the design and use of head-worn displays (HWDs). Background: This review draws heavily from both the basic vision literature and applied HWD literature in order to help provide insight for minimizing the effects of binocular rivalry when HWDs are worn. Method: Included in this review are articles and books found cited in other works as well as articles and books obtained from an Internet search. Results: Issues discussed and summarized are (a) characteristics of binocular rivalry, (b) stimulus factors affecting rivalry, (c) cognitive variables affecting rivalry, and (d) tasks affected by rivalry. Conclusion: This paper offers a set of recommendations for minimizing the effects of binocular rivalry when HWDs are used as well as recommendations for future research. Application: Considerations of the basic vision literature on binocular rivalry will provide insight for future design solutions for HWDs.
Effects of Single Versus Multiple Warnings on Driver Performance
Authors: Cummings M.L. , Kilgore Ryan M. , Wang Enlie , Tijerina Louis , Kochhar Dev S.
Published: November 2007

Objective: To explore how a single master alarm system affects drivers' responses when compared with multiple, distinct warnings. Background: Advanced driver warning systems are intended to improve safety, yet inappropriate integration may increase the complexity of driving, especially in high workload situations. This study investigated the effects of auditory alarm scheme, reliability, and collision event type on driver performance. Method: Using a 2 × 2 × 4 mixed factorial design, we investigated the impact of two alarm schemes (master vs. individual) and two levels of alarm reliability (high and low) on distracted drivers' performance across four collision event types (frontal collision warnings, left and right lane departure warnings, and warnings for a fast-approaching following vehicle). Results: Participants' reaction times and accuracy rates were significantly affected by the type of collision event and alarm reliability. The use of individual alarms, rather than a single master alarm, did not significantly affect driving performance in terms of reaction time or response accuracy. Conclusion: Even though a master alarm is a relatively uninformative warning, it produced statistically no different reaction times or accuracy results when compared with information-rich auditory icons, some of which were spatially located. In addition, unreliable alarms negatively impacted driver performance, regardless of event type or alarm scheme. Application: These results have important implications for the development and implementation of multiple driver warning systems.
Boundary value problems for the inhomogeneous polyanalytic equation II
Authors: Begehr Heinrich , Kumar Ajay
Published: November 2007

Further mixed boundary value problems are studied for the inhomogeneous polyanalytic equation in the unit disc. As in part I, see [4], the boundary conditions are some combinations of Schwarz, Dirichlet and Neumann conditions. The method applied is based on an iteration process leading from lower order equations to higher ones, see [1–3]. The method can be used to solve all kind of such mixed problems also for other kinds of complex model equations.
Stability of disk-like galaxies – Part II: The Kuzmin disk
Authors: Fiřt Roman
Published: November 2007

We prove the existence and nonlinear stability of the Kuzmin disk, a polytropic steady state of the Vlasov–Poisson system widely used in astrophysics, which has infinite support, but finite mass. As in Part I we use the variational approach by REIN and GUO.
Oscillation of certain even-order neutral differential equations with distributed delay and damping term
Authors: Chen Da-Xue , Zhou Shu-Qing , Long Yu-Hua
Published: November 2007

In this paper, we investigate the oscillation of certain even-order neutral differential equations with distributed delay and damping term, and obtain several classes of sufficient conditions for the oscillation of all of its solutions, which generalize some known results. We also give some examples to illustrate the applicability of our results.
Supercritical fluid extraction of thorium from tissue paper matrix employing organophosphorus reagents
Authors: Kumar Pradeep , Pal Ankita , Saxena M. K. , Ramakumar K. L.
Published: November 2007

Feasibility of supercritical CO2 extraction of thorium from tissue paper matrix was studied and various organophosphorus reagents (TBP, TOPO, TPP, TPPO, TBPO) were evaluated as co-solvent. Effects of pressure (100–300 atm), temperature (313–353 K), flow rate (0.5–3 mL min−1), static time (0–40 min) and extraction time (5–40 min) on thorium extraction efficiency were investigated. Pressure of 200 atm, temperature of 333 K, CO2 flow rate of 2 mL min−1, 20 min static period followed by 20 min of extraction were found to be optimum. Under optimum conditions employing various organophosphorus reagents as co-solvent, extraction efficiency indicated the trends: (i) Among phosphates, if aliphatic group attached to P was replaced by aromatic group, then extraction efficiency decreased e.g. TBP (53%±8%) and TPP (39%±5%). (ii) Among the phosphine oxides, higher the aliphatic chain length attached to P, higher was the extraction efficiency e.g. TOPO (68%±4%) and TBPO (50%±9%). (iii) In case of phosphine oxides, if phenyl group was attached to P i.e. TPPO (59%±15%) then extraction efficiency was intermediate to TOPO and TBPO. (iv) Between phosphates and phosphine oxides, for aliphatic hydrocarbons, the extraction efficiencies were comparable e.g. TBP and TBPO. For aromatic ring, extraction efficiency was higher in phosphine oxides e.g. TPP and TPPO. Both TBPO and TPP have shown higher extraction efficiency in combination with TBP. The solvents dissolving oraganophosphorus reagents were found to influence extraction efficiency. The extraction efficiency was found to decrease slightly with increasing aliphatic chain length of the alcohol. The maximum extraction efficiency was obtained with 0.2 M TOPO in methanol where thorium was extractable with 68%±4 efficiency.
Synergistic extraction of Ce(III), Tb(III) and Lu(III) with a mixture of hexafluoroacetylacetone and triphenylphosphineoxide in benzene
Authors: Rizvi Moazzaz Ali , Ali Akbar , Iqbal Mohammad Saeed
Published: November 2007

The synergistic solvent extraction of trivalent lanthanides such as Ce(III), Tb(III) and Lu(III) has been studied with a mixture of hexafluoroacetylacetone (HHFA) acting as an acidic chelating agent and triphenylphosphine oxide (TPPO) as a neutral ligand in benzene from aqueous solution of pH 2.5 having ionic strength 0.01 mol dm−3(K+/H+, Cl−). The composition of the synergistic adduct has been determined by slope analysis method and found to be M(HFA)3·2TPPO [M=Ce(III), Tb(III) Lu(III)]. The effect of various anions and cations on the extraction of these metal ions has also been studied and only oxalate among the anion and Cr(III) among the cations has some deleterious effect. The formation constant and separation factor from various metal ions have also been determined and discussed.
Modellierung und Simulation komplexer Messvorgänge mittels der Monte-Carlo-Methode (Modelling and Simulation of Complex Measurement Settings using the Monte-Carlo Method)
Authors: Wolf Marco , Müller Martin , Rösslein Matthias
Published: November 2007

Die Messunsicherheitsberechnung gewinnt zunehmend an Bedeutung, da nur mit einer Aussage über die Güte der Resultate einer Messung eine Vergleichbarkeit mit anderen Ergebnissen möglich ist. Das erste GUM-Supplement führt eine Monte-Carlo-Methode zur Berechnung der Messunsicherheit ein, die nicht den Einschränkungen der Unsicherheitsfortpflanzung unterliegt. Sie verwendet die vollständige Information beliebiger Eingangsverteilungen und setzt keine Linearisierbarkeit der Modellgleichung voraus. Die Software MUSE verwendet diese Berechnungsmethode und unterstützt den Anwender bei der Modellierung komplexer Messsysteme. Dazu werden Basismodelle verwendet, die der Modellierung von Messszenarien dienen können. Der Messprozess selbst wird modularisiert, wodurch man an Übersichtlichkeit und Strukturiertheit gewinnt.
Messunsicherheit bei der Bestimmung von Rauheitskennwerten mit Tastschnittgeräten (Uncertainty of Measurement in the Determination of Roughness Parameters Using Contact Stylus Instruments)
Authors: Krüger-Sehm Rolf , Seewig Jörg
Published: November 2007

Es wird ein Modell vorgestellt, das die Unsicherheitsquellen vom Antastvorgang bis zur Berechnung einzelner Rauheitskenngrößen beschreibt. Dabei soll verdeutlicht werden, wie sich in Abhängigkeit vom Grad der Kenntnis der Unsicherheitsquellen die Unsicherheit des Messergebnisses verändert. Beispielhaft wird gezeigt, wie durch die Beschreibung einer Oberflächenkenngröße als Zufallsvariable gegenüber der bisherigen Praxis die Messunsicherheit genauer angegeben werden kann.
Koordinatenmessung mit industrieller Röntgen-Computertomografie (Coordinate Measuring with Industrial X-Ray Computed Tomography)
Authors: Hiller Jochen , Kasperl Stefan , Hilpert Uwe , Bartscher Markus
Published: November 2007

Die industrielle Computertomografie (CT) hat in der letzten Zeit eine deutliche Weiterentwicklung in Richtung Koordinatenmesstechnik erfahren. Zahlreiche Messaufgaben können bereits sinnvoll und konkurrenzfähig gegenüber anderer Messtechnik gelöst werden. Dieser Beitrag beschreibt anhand eines speziellen Prüfkörpers und ausgewählter Mess- und Kenngrößen dimensionelle Messeigenschaften industrieller CT-Anlagen. Es wird gezeigt, wie sich unterschiedliche physikalische Effekte auf diese dimensionellen Messgrößen auswirken können. Darüber hinaus wird ein Korrekturverfahren vorgestellt, mit dem die Genauigkeit der mit CT ermittelten Geometriedaten erhöht werden kann.
Ein geometrisches Normal zur Prüfung von Röntgen-Mikro-Computertomografiemesssystemen (A Geometrical Standard for Testing of X-Ray Computer Tomography)
Authors: Neugebauer Michael , Hilpert Uwe , Bartscher Markus , Gerwien Norbert , Kunz Stefan , Neumann Frank , Goebbels Jürgen , Weidemann Gerd
Published: November 2007

Es wird ein neu entwickeltes geometrisches Normal zur Prüfung von Röntgen-Mikro-Computertomografiemesssystemen (μCT-Messsystemen) sowie ein Verfahren zur Herstellung und Kalibrierung beschrieben. Das Normal ermöglicht die Prüfung von μCT-Messsystemen mit den Verfahren der klassischen Koordinatenmesstechnik nach ISO 10360 bzw. VDI/VDE 2617 sowie dem Verfahren des Soll-Ist-Vergleiches von Referenz- und μCT-Messdaten.
Chirp-Kalibriernormale für Oberflächenmessgeräte (Chirp Calibration Standards for Surface Measuring Instruments)
Authors: Krüger-Sehm Rolf , Bakucz Peter , Jung Lena , Wilhelms Harald
Published: November 2007

In diesem Beitrag wird ein „Chirp”-Oberflächennormal vorgestellt. Es ist dafür vorgesehen, mit einer Serie von verschiedenen Ortsfrequenzen das Übertragungsverhalten von Oberflächenmessgeräten zu testen. Die Topografie des Normals enthält eine abgestufte Folge von Sinuswellen, deren Abstände, Steigungen und Krümmungen durch den Synthese- und Fertigungsprozess genau bekannt sind. Die Oberfläche des Normals wird durch einen Diamant-Drehprozess hergestellt. Bei der Erzeugung der NC-Steuerdaten wird mittels morphologischer Operationen der Einfluss der Werkzeuggeometrie berücksichtigt. Erste Ergebnisse von Messungen am Chirp-Normal mit Interferenzmikroskopen und Tastschnittgeräten werden gezeigt.
IR Voltage in Crevices during Crevice Corrosion and Sacrificial Cathodic Protection
Authors: Pickering Howard W.
Published: November 2007

This paper describes work related to Konrad G. Weil's research interests while a visiting scholar in the Pickering Laboratory at Penn State University in the period, 1991–2003. Specifically, this paper describes the role of IR voltage in (i) causing corrosion attack and hydrogen evolution and absorption inside crevices in iron, and (ii) increasing the lifetime of environmentally friendly electroplates used for corrosion prevention. I is the current flowing in a cavity's (e.g., crevice's) electrolyte and R is the resistance of this electrolyte path.
Synthesis of Zirconium Nanoparticles by Ultrafast Laser Ablation
Authors: Golightly Justin S. , Castleman A.W.
Published: November 2007

We report the results of the ablation of a zirconium rod in isopropyl alcohol employing a titanium sapphire femtosecond laser system operated at sub-800nm wavelengths with a fluence of 2mJ/pulse and a 10Hz pulse rate. Ablation of zirconium was investigated under two different focal regimes, resulting in ablation with different power densities. Optimally, the femtosecond laser system produces pulses of 100 femtoseconds; however, experiments were also performed in which the temporal nature of the femtosecond pulse was adjusted by stretching the pulse to minimize supercontinuum formation. The resultant nanoparticles displayed size distributions with mean values of 12 to 15nm. Optical activity of zirconium nanoparticles is addressed.
Resistive Switching in Ge0.3Se0.7 Films by Means of Copper Ion Migration
Authors: Schindler C. , Guo X. , Besmehn A. , Waser R.
Published: November 2007

Cu/Ge0.3Se0.7/Pt cells were prepared and bipolar resistive switching in Ge0.3Se0.7 films by means of copper ion migration was examined. The cell was switched from the high to the low resistance state at about -50mV, and it was switched back to the high resistance state at about 100mV. The resistance ratio between the high and the low state was up to 200. Up to approximately 104 switching cycles were achieved. Pulse measurements showed that the two resistance states were tuneable by varying the applied voltage and the pulse length. Therefore, it is possible to store more than one bit per cell. The current density is independent of the electrode diameter, indicating that the cell can be scaled down to the range of nanometers. Due to the low switching voltages, non-destructive read out operation, high storage density, and scalability, such cells are promising for future memory applications.
Microcalorimetry of Electrochemical Reactions at Submonolayer Conversions
Authors: Schuster Rolf , Rösch R. , Timm A. E.
Published: November 2007

We measured heat effects upon underpotential deposition or dissolution of a fraction of a monolayer of Cu on a Au surface. Temperature changes due to electrochemical reactions were pyroelectrically detected at the backside of a 100μm thin polycrystalline Au electrode. Pulsed electrochemical deposition or dissolution during 10ms intervals prevented significant loss of heat into the electrolyte on that time scale. The combination of both,i.e., pulsed electrochemical reactions at a thin electrode with low heat capacity, leads to unprecedented sensitivity. In addition, we compare the experimental temperature transients with the temperature evolution simulated for our experimental setup. Interferences stemming from mechanical deformation of the electrode foil due to potential-induced surface stress are also discussed.
In SituInvestigations on the Oxidation of Metals
Authors: Martin Manfred , Lakshmi N. , Koops U. , Yoo H.-I.
Published: November 2007

High temperature oxidation processes of metals are important solid state reactions from a fundamental point of view and also concerning technical applications. The kinetics of these solid state reactions was investigatedin situby X-ray absorption spectroscopy (XAS), optical microscopy and X-ray diffraction (XRD) at elevated temperatures and defined oxygen partial pressures. Oxidation of thin cobalt foils in air was studied by means of quick X-ray absorption spectroscopy (QEXAFS) at the CoKedge. By de-convolution of the spectra, the fractions of Co, CoO and Co3O4were determined as a function of time. During oxidation of the intermetallic compound CoGa only Ga is selectively oxidized andβ-Ga2O3is formed. Usingin situoptical microscopy and evaluating the interference colors it is shown that different crystallographic orientations of the intermetallic compound CoGa result in oxide scales of different thicknesses. Finally we present first experimental results on the oxidation of zirconium which were obtained byin situX-ray diffraction (XRD). The results show that both monoclinic and tetragonal ZrO2exist in the oxide scale. The latter one is probably stabilized by compressive stress near the Zr/ZrO2interface.
A High-Temperature Mössbauer Study of the Iron Nitrides
Authors: Bartels O. , Becker K.D.
Published: November 2007

Mössbauer spectra of the iron nitrides have been measured at room temperature and at 550°C. In the case of the room temperature spectrum ofγ′-Fe4N, a fit strategy is reviewed which accounts for two spectroscopically inequivalent iron Fe(1) sites due to the simultaneous presence of magnetic and quadrupolar interactions. In contrast, the high-temperature spectra ofγ′-Fe4N allow for the direct determination of the quadrupolar interactions at Fe(1) sites. In the case ofɛ-Fe3N1+x, the stoichiometry dependent magnetically-split room temperature spectra demonstrate the extensive ordering of nitrogen in the compound. At 550°C, spectra have been measured at various defined thermodynamic conditions of controlled nitrogen activity. The quadrupole-split spectra high-temperature are discussed in relation to structure and disorder of the material. In particular, it is shown that the composition dependent high-temperature spectra ofɛ-Fe3N1+xcan be modelled in the framework of a simple two-site model.
Characterization of V-W and Mo-W Mixed Oxide Catalysts for the Selective Oxidation of Acrolein to Acrylic Acid
Authors: Schmitt C. , Giebeler L. , Schierholz R. , Endres S. , Fasel C. , Vogel H. , Fuess Hartmut
Published: November 2007

The ternary Mo-W and V-W mixed oxides are part of the quaternary V-Mo-W catalyst system which is highly active and selective for the important and widely used selective oxidation of acrolein to acrylic acid. Both subsystems are active and selective catalysts for this reaction, varying with composition. The microstructure of the samples has been identified as homogeneously distributed nanocrystalline grains within the shell of the hollow balls that are typical for the spray-drying process. The crystallite sizes differ between the two sample series and depend on the composition as well. The test for the catalytic performance revealed the highest selectivity and yield in acrylic acid production for the V-W catalyst with 70% tungsten content, although tungsten oxide is known to be chemically inactive. The active components vanadium oxide and molybdenum oxide presumably are the most selective for the reaction of acrolein to acrylic acid when their structure and cluster size is stabilized by a stable and inert WO3 matrix. The heating of the samples during the catalytic performance test caused a visible growth of the nanocrystallites which also protruded from the surface of the hollow balls. The structural rearrangements led to an increase of the catalytic performance.
High Resolution FTIR and Diode Laser Supersonic Jet Spectroscopy of the N = 2 HF Stretching Polyad in (HF)2 and (HFDF): Hydrogen Bond Switching and Predissociation Dynamics
Authors: He Yabai , Müller Holger B. , Quack Martin , Suhm Martin A.
Published: November 2007

We report Fourier transform infrared (FTIR) and high resolution diode laser spectra (∼ 1MHz instrumental bandwidth) obtained in cooled absorption cells as well as in a supersonic jet expansion for the N = 2 polyad region of the HF-stretching vibrations of (HF)2, HFDF and DFHF. Three vibrational transitions have been observed for (HF)2 and two for both monodeuterated isotopomers. For (HF)2 we have identified and analysed the observed transitions of the polyad member 22 of the type Δ K
a = 0 and Δ K
a = ± 1 up to rotational sublevel Δ K
a = 3. Band centers as well as rotational constants of all four K
a states have been determined. The tunneling splittings due to hydrogen bond switching for these four K
a states have been investigated, with the Δ K
a = 0 up to Δ K
a = 2 sublevels having tunneling symmetry Γ
vt = A
+ for the lower tunneling states, and switching periods ranging from 158ps for K
a = 0 to 1.35ns for K
a = 2. A tunneling level inversion is found at Δ K
a = 3, leading to a symmetry Γ
vt = B
+ for the lower tunneling state of this K
a-sublevel. The vibrational assignment of the measured spectra of (HF)2 was established by comparison with the monodeuterated isotopomers HFDF and DFHF. For HFDF we have identified and analysed five subbands between 7600cm-1 and 7730cm-1. We have determined the spectroscopic constants of the rotational levels Δ K
a = 0 and Δ K
a = 1 for the vibrationally excited state and of the levels of Δ K
a = 1 and Δ K
a = 2 of the ground state, the latter from combination differences. From the measurements in a supersonic jet expansion we determined the predissociation line width of the N = 22, K
a = 1 to be about 120MHz for the Γ
vt = A
+ tunneling state of (HF)2 and about 90MHz for Γ
vt = B
+. For the Δ K
a = 0 level of N = 22 we obtained predissociation line widths ranging around 100MHz, similar to those of the Δ K
a = 1 level. In the case of HFDF, the predissociation line width of Δ K
a = 1 is about 80MHz. Predissociation lifetimes for these levels with the unbonded HF stretching excited thus are in the range of about 1 to 2ns. The predissociation width in the N = 21 level is uncertain by about a factor three with lg(Δν/MHz) = (3 ± 0.5) and in N = 23 it is about 600MHz corresponding to rounded lifetimes of 0.1ns and 0.3ns when the bonded HF stretching is excited thereby demonstrating strongly mode selective predissociation rates in the N = 2 polyad. Under thermal equilibrium conditions we derived the pressure broadening coefficient for (HF)2 (γ = (6 ± 1) × 10-4cm-1/mbar in the wavenumber range between 7713cm-1 and 7721cm-1 for total gas pressures between 10 and 60mbar, all values as full widths half maximum). For absolute frequency calibrations we have remeasured the first overtone transitions of the monomer HF with much improved precision between P(5) (7515.80151cm-1) and R(7) (7966.22188cm-1).
A Refined All-Atom Model for the Ionic Liquid 1-n-Butyl 3-Methylimidazolium bis(Trifluoromethylsulfonyl)imide [bmim][Tf2N]
Authors: Zhao Wei , Eslami Hossein , Cavalcanti Welchy Leite , Müller-Plathe Florian
Published: November 2007

A refined flexible all-atom model for a room temperature ionic liquid, 1-n-butyl 3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]), is reported here. Extensive molecular dynamics simulations were performed to check the validity of this model. We found that the thermodynamic and dynamic properties such as density, isobaric expansivity, isothermal compressibility, and self-diffusion coefficient described by the present model are in good agreement with experimental observations. Based on the calculated results, there has been a considerable improvement in the force field with respect to the previous model by Lopes et al. [15,16].
Acute exercise increases adipose tissue interstitial adiponectin concentration in healthy overweight and lean subjects
Authors: Højbjerre Lise , Rosenzweig Mary , Dela Flemming , Bruun Jens M , Stallknecht Bente
Published: November 2007

Objective

We studied how an acute bout of exercise influences expression and concentration of adiponectin and regulators of adiponectin in adipose tissue and plasma.

Design and methods

Eight overweight and eight lean males were examined by large-pore microdialysis in s.c. abdominal adipose tissue (SCAAT) and had arterialized blood sampled. On one day subjects rested for 3 h, exercised for 1 h at 55% of maximal oxygen uptake and rested again for 2.5 h, and on another day subjects rested for 6.5 h. On the day including exercise SCAAT was biopsied before and after exercise.

Results

Exercise increased the SCAAT interstitial adiponectin concentration in both overweight and lean subjects and concentrations did not differ between groups. Plasma adiponectin did not increase during exercise and was similar in overweight and lean subjects. Adiponectin mRNA in SCAAT decreased during exercise and was similar in overweight and lean subjects. Surprisingly, the interstitial adiponectin concentration in SCAAT was only 20% of the plasma concentration. SCAAT interleukin-6 (IL-6) microdialyzate and plasma concentrations and SCAAT IL-6 mRNA increased during exercise in both groups. Tumor necrosis factor-α (TNF-α) plasma concentration did not change during exercise in any of the groups, but SCAAT TNF-α mRNA increased after exercise in both groups. Furthermore, exercise decreased SCAAT leptin mRNA with no change in resistin mRNA.

Conclusions

Acute exercise increases adipose tissue interstitial adiponectin concentration in both overweight and lean subjects with no major changes in plasma adiponectin concentration. The interstitial concentration of adiponectin in SCAAT is only 20% of that in plasma.
Glucocorticoids and Cardiovascular Disease
Authors: Walker Brian R
Published: November 2007

Chronic excessive activation of glucocorticoid receptors induces obesity, insulin resistance, glucose intolerance, dyslipidaemia and hypertension. Subtle abnormalities of the hypothalamic–pituitary–adrenal axis and/or of tissue sensitivity to glucocorticoids are also associated with these cardiovascular risk factors in patients with the metabolic syndrome. Furthermore, glucocorticoids have direct effects on the heart and blood vessels, mediated by both glucocorticoid and mineralocorticoid receptors and modified by local metabolism of glucocorticoids by the 11β-hydroxysteroid dehydrogenase enzymes. These effects influence vascular function, atherogenesis and vascular remodelling following intra-vascular injury or ischaemia. This article reviews the systemic and cardiovascular effects of glucocorticoids, and the evidence that glucocorticoids not only promote the incidence and progression of atherogenesis but also modify the recovery from occlusive vascular events and intravascular injury. The conclusion is that manipulation of glucocorticoid action within metabolic and cardiovascular tissues may provide novel therapeutic avenues to combat cardiovascular disease.
Mifepristone (RU 486) in Cushing's syndrome
Authors: Johanssen Sarah , Allolio Bruno
Published: November 2007

Context

Mifepristone (RU 486) blocks the action of cortisol by binding to the glucocorticoid receptor and, therefore, is of potential therapeutic value in Cushing's syndrome. However, research in endogenous hypercortisolism has been hampered by the controversy related to the use of mifepristone for inducing abortion. Currently, new studies are planned to better define the role of RU 486 in Cushing's syndrome. This paper reviews the available evidence concerning the therapeutic effects and adverse events of RU 486 in Cushing's syndrome.

Evidence acquisition

Original articles and reviews were identified using a PubMed search strategy covering the time period until February 2007.

Evidence synthesis

Treatment of Cushing's syndrome with mifepristone has been reported in a total of 18 patients, with daily doses ranging from 5 to 30 mg/kg. Case reports indicate that the mifepristone-induced receptor blockade may lead to significant clinical improvement in patients with Cushing's syndrome in whom surgery and inhibitors of adrenal steroidogenesis fail to control hypercortisolism. Due to its rapid onset of action, mifepristone may be particularly useful in acute crises, e.g. in cortisol-induced psychosis. Side effects include adrenal insufficiency and, as a result of its antiprogestin action, endometrial hyperplasia in long-term treatment. Adrenal insufficiency can be assessed only by careful clinical evaluation, as the hormonal parameters are not reliable during receptor blockade, and is rapidly reversed by exogenous dexamethasone. Well-designed larger clinical trials are needed to better assess the value of this interesting drug in the treatment of Cushing's syndrome.
Population Dynamics and Distribution Patterns of Longfin Smelt in the San Francisco Estuary
Authors: Rosenfield Jonathan A. , Baxter Randall D.
Published: November 2007

The San Francisco Estuary supports several endemic species of fish and the southernmost populations of other species. Many of these native species and populations are imperiled or have experienced recent population declines that indicate a general decline in the estuary's capacity to support pelagic fish species. We studied the distribution and abundance of one of the estuary's native species, longfin smeltSpirinchus thaleichthys, using data from three long‐term aquatic sampling programs. Each of the sampling programs we studied revealed a substantial reduction in the abundance of longfin smelt. These trends support the idea that the estuary's capacity to support pelagic fish species has been significantly reduced over the past three decades. Longfin smelt in the estuary displayed consistent patterns in relative abundance and distribution during their life cycle. We also found significant, but weak, spatial autocorrelation among sampling stations. These patterns in distribution reveal differential habitat use and migratory behavior. Managers can use these insights into longfin smelt distribution patterns to improve interpretation of sampling program results.
Anticipated Climate Warming Effects on Bull Trout Habitats and Populations Across the Interior Columbia River Basin
Authors: Rieman Bruce E. , Isaak Daniel , Adams Susan , Horan Dona , Nagel David , Luce Charles , Myers Deborah
Published: November 2007

A warming climate could profoundly affect the distribution and abundance of many fishes. Bull trout Salvelinus confluentus may be especially vulnerable to climate change given that spawning and early rearing are constrained by cold water temperatures creating a patchwork of natal headwater habitats across river networks. Because the size and connectivity of patches also appear to influence the persistence of local populations, climate warming could lead to increasing fragmentation of remaining habitats and accelerated decline of this species. We modeled the relationships between (1) the lower elevation limits of small bull trout and mean annual air temperature and (2) latitude and longitude across the species' potential range within the interior Columbia River basin of the USA. We used our results to explore the implications of the climate warming expected in the next 50 or more years. We found a strong association between the lower elevation limits of bull trout distributions and longitude and latitude; this association was consistent with the patterns in mean annual air temperature. We concluded that climate does strongly influence regional and local bull trout distributions, and we estimated bull trout habitat response to a range of predicted climate warming effects. Warming over the range predicted could result in losses of 18‐92% of thermally suitable natal habitat area and 27‐99% of large (>10,000‐ha) habitat patches, which suggests that population impacts may be disproportionate to the simple loss of habitat area. The predicted changes were not uniform across the species' range, and some populations appear to face higher risks than others. These results could provide a foundation for regional prioritization in conservation management, although more detailed models are needed to prioritize actions at local scales.
Greywater recycling: treatment options and applications
Authors: Pidou M. , Memon F. A. , Stephenson T. , Jefferson B. , Jeffrey P.
Published: November 2007

Wastewater is an immense resource that could find significant applications in regions of water scarcity. Greywater has particular advantages in that it is a large source with a low organic content. Through critical analysis of data from existing greywater recycling applications, this paper presents a review of existing technologies and applications by collating a disparate information base and comparing/contrasting the strengths and weaknesses of different approaches. Simple technologies and sand filters have been shown to have a limited effect on greywater; membranes are reported to provide good solids removal but cannot efficiently tackle the organic fraction. Alternatively, biological and extensive schemes achieve a good general treatment of greywater with particularly effective removal of organics. The best overall performances were observed within schemes that combine different types of methods to ensure effective treatment of all the fractions.
Hydraulic conductivity of tyres in landfill drainage systems
Authors: Hudson A. P. , Beaven R. P. , Powrie W. , Parkes D.
Published: November 2007

Whole or shredded scrap tyres are sometimes proposed as an alternative to conventional aggregates in landfill drainage systems. Landfill basal drainage systems are, however, subjected to large overburden stresses from the overlying waste, which may compress a tyre drainage layer, thereby reducing its porosity and hence its effectiveness. Previous work has indicated that tyre drainage layers will remain effective under high stresses, but tests have in the main been restricted to small (<100 mm) shred sizes. The use of coarser shreds or even whole tyres for landfill drainage systems may be advantageous as they are more economical to produce and may be less prone to clogging than smaller shreds. In the current paper, the results of large-scale (2 m diameter) tests to investigate the variation in hydraulic conductivity (permeability) with stress of 50, 200 and 450 mm nominal size tyre shreds are compared with data from the literature for smaller-size shreds and whole tyres. Tests were carried out at vertical stresses up to 600 kPa, representing landfill depths of up to about 60 m. Potential errors in laboratory test procedures are highlighted and the influence of scale and the relative test chamber to particle size on the results is discussed. It is concluded that a chamber to particle size ratio of at least 6 is needed with a rigid walled permeameter, if errors owing to peripheral flow effects are to be avoided. Relationships between shred size and drainage properties are investigated: no clear correlation between tyre shred size and drainage properties in the particle size range 50–450 mm is found. Whole tyres, however, generally have a slightly higher hydraulic conductivity, while samples containing a significant proportion of material less than 20 mm in size have generally a lower hydraulic conductivity at a given vertical stress than clean samples of larger shreds.
Stabilised mineral–biomass mixtures in groundwork: pilot study
Authors: Chan B. K. C. , Dudeney A. W. L.
Published: November 2007

Based on fundamental characteristics previously determined, two types of pilot studies were carried out to inform possible future full-scale field application of stabilised mineral—biomass mixtures as components of brownfield restoration projects. To gain a preliminary confirmation of properties, four vertical cylinders containing mixed compacted material were used to represent cylindrical volumes within supposedly continuous mixed emplacements. A 100 t field emplacement based on an alkaline model was constructed within a clay lining. This was regulated by an Environment Agency waste management licence. During 18 months' monitoring, optical surveys detected no significant mechanical movement and the emplacement remained essentially dry despite periods of heavy rain and flooding. No landfill gas was detected in boreholes within the compact mass. Pore water recovered during final excavation contained low but significant levels of ammonia and heavy metals, thus justifying lining. The results should form the basis of development to a full-scale prototype emplacement (∼10 5 t, 1 ha) as a means of assessing this technology for reusing bulk surplus industrial products under regulation.
Does war beget child aggression? Military violence, gender, age and aggressive behavior in two Palestinian samples
Authors: Qouta Samir , Punamäki Raija‐Leena , Miller Thomas , El‐Sarraj Eyad
Published: November 2007

We examined, first, the relations between children's exposure to military violence and their aggressive behavior and the role of age and gender in that relation in two Palestinian samples. Second, we tested parenting practices as a moderator of the relation between exposure to military violence and aggressive behavior, and third, whether exposure to military violence of different nature (direct victimization versus witnessing) has specific associations with different forms of aggression (reactive, proactive and aggression‐enjoyment). Study I was conducted in a relatively calm military‐political atmosphere in Palestine‐Gaza, and included 640 children, aged 6–16 years whose parents (N=622) and teachers (N=457) provided reports. Older children (≥12 years) provided self‐reports (N=211). Study II included 225 Palestinian children aged 10–14‐year, who participated during a high‐violence period of the Al Aqsa Intifada characterized by air raids, killing and destruction. Results showed that witnessing severe military violence was associated with children's aggressive and antisocial behavior (parent‐reported) in study I, and with proactive, reactive and aggression‐enjoyment (child‐reported) in the study II. As hypothesized, good and supporting parenting practices could moderate the link between exposure to military violence and aggressive behavior. Aggr. Behav. 34:231–244, 2008. © 2007 Wiley‐Liss, Inc.
Children's dietary recalls from three validation studies: types of intrusion vary with retention interval
Authors: Baxter Suzanne Domel , Hardin James W. , Smith Albert F. , Royer Julie A. , Guinn Caroline H.
Published: November 2007

Using previously collected data of fourth‐grade children observed eating school meals and then interviewed, we categorized intrusions (food items reported but not observed eaten) as stretches (on the child's tray) or confabulations (not on the child's tray). We investigated intrusions, confabulations, and stretches and the role of liking, at different retention intervals (morning interviews about the previous day's intake; evening interviews about that day's intake) and under different reporting‐ order prompts (forward; reverse). As retention interval between consumption and report increased, the likelihood (1) increased that reported items were intrusions, that reported items were confabulations and that intrusions were confabulations; and (2) was constant that reported items were stretches. Results concerning reporting‐order prompts were inconclusive. Liking ratings were higher for matches (reports of items observed eaten) than stretches, for confabulations than stretches, and for matches than omissions (unreported items observed eaten), but did not vary by retention interval or reporting‐order prompts. Copyright © 2007 John Wiley & Sons, Ltd.
Structure, interaction and property of amino‐functionalized imidazolium ILs by molecular dynamics simulation and Ab initio calculation
Authors: Yu Guangren , Zhang Suojiang , Zhou Guohui , Liu Xiaomin , Chen Xiaochun
Published: November 2007

Imidazolium ionic liquids (ILs) can be functionalized by introducing NH2, which were found to be excellent solvents for CO2 capture and electrophile separation, however, some disadvantages, e.g., the relatively high viscosities, limit their eventual large‐scale applications. To understand the influences of amino addition on their properties and promote their applications, the microstructure and interionic interaction in two selected amino‐functionalized imidazolium ILs, 1‐aminoethyl‐3‐methylimidazolium hexafluorophosphate and 1‐aminopropyl‐3‐butylimidazolium tetrafluoroborate, are studied both for bulk liquid by using molecular dynamics simulations and for isolated ion pair by using ab initio calculations. It is found that the amino addition does not remarkably affect the organization of anions around C2‐site, C4‐site, and C5‐site on imidazolium ring, while it participates in the cation–anion interaction as a new strong site where anions strongly organize around NH2 and form strong ion‐type hydrogen bonds. The condensed phase simulations indicate that their ionic self‐diffusion coefficients are on the order of 10−13 m2 s−1 at room temperature, roughly 2 order of magnitude lower than that of conventional imidazolium ILs without NH2; the isolated ion pair calculations show that such terminal amino‐associated interaction reduces the flexibility of alkyl side chains and increases the cation–anion interaction; and these results are qualitatively consistent with their higher experimental viscosities. © 2007 American Institute of Chemical Engineers AIChE J, 2007