30,431 research outputs found

    Phonon density of states and compression behavior in iron sulfide under pressure

    Get PDF
    We report the partial phonon densities of states (DOS) of iron sulfide, a possible component of the rocky planet's core, measured by the Fe-57 nuclear resonant inelastic x-ray scattering and calculate the total phonon DOS under pressure. From the phonon DOS, we drive thermodynamic parameters. A comparison of the observed and estimated compressibilities makes it clear that there is a large pure electronic contribution in the observed compressibility in the metallic state. Our results present the observation of thermodynamic parameters of iron sulfide with the low-spin state of an Fe2+ ion at the high density, which is similar to the condition of the Martian core

    Incidental threat during visuospatial working memory in adolescent anxiety: an emotional memory-guided saccade task

    Get PDF
    BackgroundPediatric anxiety disorders are among the most common psychiatric mental illnesses in children and adolescents, and are associated with abnormal cognitive control in emotional, particularly threat, contexts. In a series of studies using eye movement saccade tasks, we reported anxiety-related alterations in the interplay of inhibitory control with incentives, or with emotional distractors. The present study extends these findings to working memory (WM), and queries the interaction of spatial WM with emotional stimuli in pediatric clinical anxiety. MethodsParticipants were 33 children/adolescents diagnosed with an anxiety disorder, and 22 age-matched healthy comparison youths. Participants completed a novel eye movement task, an affective variant of the memory-guided saccade task. This task assessed the influence of incidental threat on spatial WM processes during high and low cognitive load. ResultsHealthy but not anxious children/adolescents showed slowed saccade latencies during incidental threat in low-load but not high-load WM conditions. No other group effects emerged on saccade latency or accuracy. ConclusionsThe current data suggest a differential pattern of how emotion interacts with cognitive control in healthy youth relative to anxious youth. These findings extend data from inhibitory processes, reported previously, to spatial WM in pediatric anxiety

    Rotating Black Hole Entropy from Two Different Viewpoints

    Full text link
    Using the brick-wall method, we study the entropy of Kerr-Newman black hole from two different viewpoints, a rest observer at infinity and zero angular momentum observer near horizon. We investigate this with scalar field in the canonical quantization approach. An observer at infinity can take one of the two possible frequency ranges; one is with positive frequencies only and the other is with the whole range including negative frequencies. On the other hand, a zero angular momentum observer near horizon can take positive frequencies only. For the observer at infinity the superradiant modes appear in either choice of the frequency ranges and the two results coincide. For the zero angular momentum observer superradiant modes do not appear due to absence of ergoregion. The resulting entropies from the two viewpoints turn out to be the same.Comment: LaTeX 18 pages, 2 figures, Minor modifications in section 3(ZAMO

    Comparison of certain microbial counting methods which are currently commonly used in the soaking process

    Get PDF
    This study examines the interrelation of the test methods which are commonly applied in the leather industry for hide or skin soaking. For this purpose, five different bactericides were given during the soaking processes and after the presoaking process. The processes were measured at the first 20th min, 24th and 48th h. For this purpose, two different ATP test kits, dip slide and agar pour plate method were used in order to determine the microorganism load as RLU (Relative Light Units) or CFU (Colony Forming Units)/ml. The values with all methods were identified as highly different from each other, while the statistical analyses indicated positive Pearson correlation coefficients especially between the 24th and 48th h measurements. The appearance of a positive correlation between the different methodsunder constant conditions implied the effectiveness of the bactericides to the customer at the factory environment. The ATP test method and dip slide methods that are commonly used in the market are correct and convenient methods offered by some companies

    The quasar Q0957+561: Lensed CO emission from a disk at z~1.4?

    Full text link
    In recent years large efforts have been made to detect molecular gas towards high redshifted objects. Up to now the literature reports on only two cases of CO-detection in quasars at a redshift between 1 and 2 - Q0957+561, a gravitationally lensed system at z=1.41 (Planesas et al. 1999), and HR10 at z=1.44 (Andreani et al. 2000). According to Planesas et al. (1999), 12CO(2-1) emission was detected towards both the lensed images of Q0957+561 with the IRAM Plateau de Bure Interferometer (PdBI). In contrast to the optical spectra of the two images which support the idea that they are images of one and the same object, the CO-spectra were surprisingly different: the southern image (named CO-B) shows a single blueshifted line whereas a double-peaked line profile with a blue- and a redshifted part appears towards the northern image (CO-A). Based on the observations and on simulations with a gravitational lens program, we are tempted to argue that the line profile traces the presence of molecular gas of a disk in the host galaxy around the quasar. We have now new observations with the PdBI providing the necessary sensitivity to corroborate our disk model.Comment: 4 pages, 1 figure, to appear in "Proceedings of the 4th Cologne-Bonn-Zermatt-Symposium", ed. S. Pfalzner, C. Kramer, C. Straubmeier, and A. Heithausen (Springer Verlag

    Aryl Phosphoramidates of 5-Phospho Erythronohydroxamic Acid, A New Class of Potent Trypanocidal Compounds

    Get PDF
    RNAi and enzymatic studies have shown the importance of 6-phosphogluconate dehydrogenase (6-PGDH) in Trypanosoma brucei for the parasite survival and make it an attractive drug target for the development of new treatments against human African trypanosomiasis. 2,3-O-Isopropylidene-4-erythrono hydroxamate is a potent inhibitor of parasite Trypanosoma brucei 6-phosphogluconate dehydrogenase (6-PGDH), the third enzyme of the pentose phosphate pathway. However, this compound does not have trypanocidal activity due to its poor membrane permeability. Consequently, we have previously reported a prodrug approach to improve the antiparasitic activity of this inhibitor by converting the phosphate group into a less charged phosphate prodrug. The activity of prodrugs appeared to be dependent on their stability in phosphate buffer. Here we have successfully further extended the development of the aryl phosphoramidate prodrugs of 2,3-O-isopropylidene-4-erythrono hydroxamate by synthesizing a small library of phosphoramidates and evaluating their biological activity and stability in a variety of assays. Some of the compounds showed high trypanocidal activity and good correlation of activity with their stability in fresh mouse blood

    Noncommutative BTZ Black Hole in Polar Coordinates

    Full text link
    Based on the equivalence between the three dimensional gravity and the Chern-Simons theory, we obtain a noncommutative BTZ black hole solution as a solution of U(1,1)×U(1,1)U(1,1)\times U(1,1) noncommutative Chern-Simons theory using the Seiberg-Witten map. The Seiberg-Witten map is carried out in a noncommutative polar coordinates whose commutation relation is equivalent to the usual canonical commutation relation in the rectangular coordinates up to first order in the noncommutativity parameter θ\theta. The solution exhibits a characteristic of noncommutative polar coordinates in such a way that the apparent horizon and the Killing horizon coincide only in the non-rotating limit showing the effect of noncommutativity between the radial and angular coordinates.Comment: 14 pages, V2: minor changes, v3: reduced for clarification, a reference adde

    The view from Salford : perspectives on scholarly communications from a research-informed university

    Get PDF
    This article presents a range of perspectives on the current state of the scholarly communications sector through the lens of a research-informed university, beginning with a short overview of research at the University of Salford and followed by our assessment of what we feel is working, and indeed not working, with the current system. Based on this, we assess what we feel are the current barriers to change and both how these can be overcome and what we are doing to overcome them. Finally, we provide some commentary on what we feel is the changing open access paradigm and where all this should take us next

    Computer Simulation of the Impact of Cigarette Smoking On Humans

    Get PDF
    In this edition, emphasis has been laid on computer simulation of the impact of cigarette smoking on the population between now and the next 50 years, if no government intervention is exercised to control the behaviour of smokers. The statistical indices derived from the previous article (WAJIAR Volume 4) in the series were plugged in as input to the simulation model. The software simulation followed a statistical model. The simulation software was developed using the internationally accepted Software Engineering Methodology – the Structured System Analysis and Design Methodology (SSADM), coding by OOP and packaging by Prototyping methodologies. The simulation is intended to be predictive and to enable policy makers see the impact and dangers of cigarette smoking between now and the next 50 years if current abuse is not controlled, that is, the number of smokers likely to contact liver, brain and related diseases and who are most likely to die from these diseases. The summary of the result shows that in the next fifty years, a total of 2379591 people will likely suffer liver diseases, 2379818 people will likely suffer lung diseases, 2380297 people will likely suffer hepatitis and 2379689 will also likely suffer Brain Damage. Generally, a total of 9519395 people will likely suffer these four diseases caused by cigarette smoking and most importantly, the total number of deaths is expected to be 1903880. This result suggests that the negative impact of cigarette smoking is significant and demands immediate government intervention to avoid further population decimation. Keywords: Simulation, Software, Model, Population, Design
    • …
    corecore