Modeling void abundance in modified gravity

We use a spherical model and an extended excursion set formalism with drifting diffusive barriers to predict the abundance of cosmic voids in the context of general relativity as well as f(R) and symmetron models of modified gravity. We detect spherical voids from a suite of N-body simulations of these gravity theories and compare the measured void abundance to theory predictions. We find that our model correctly describes the abundance of both dark matter and galaxy voids, providing a better fit than previous proposals in the literature based on static barriers. We use the simulation abundance results to fit for the abundance model free parameters as a function of modified gravity parameters, and show that counts of dark matter voids can provide interesting constraints on modified gravity. For galaxy voids, more closely related to optical observations, we find that constraining modified gravity from void abundance alone may be significantly more challenging. In the context of current and upcoming galaxy surveys, the combination of void and halo statistics including their abundances, profiles and correlations should be effective in distinguishing modified gravity models that display different screening mechanisms

A checklist of the land Mollusca (Gastropoda) of the islands of São Tomé and Príncipe, with new records and description of new taxa

The first comprehensive checklists since the works of Germain in 1916 are presented for the terrestrial mollusca of São Tomé and Príncipe. The fauna currently known comprises 59 species for São Tomé, 45 for Príncipe, and a total of 86 species in the country as a whole. Seven species of terrestrial Gastropoda are newly described from the island of São Tomé and six more from the island of Príncipe. The genera involved are Cyathopoma (Cyclophoridae), Maizania and Thomeomaizania (Maizaniidae), Pseudoveronicella (Veronicellidae), Nothapalus (Achatinidae), Gulella and Streptostele (Streptaxidae), Truncatellina (Truncatellinidae), Afroconulus (Euconulidae), Principicochlea n. gen., Principotrochoidea n. gen., Thomithapsia n. gen. and Thomitrochoidea n. gen. (Urocyclidae). Most of these are from natural forest habitats and are likely to be singleisland endemics. Aporachis n. gen. (Achatinidae s.l.) and Apothapsia n. gen. (Helicarionidae) are also described to accommodate previously known species. Rachis burnayi (Dohrn) and R. eminula (Morelet) are placed in the genus Gittenedouardia. Additional new island records are of ten species on São Tomé, one on Príncipe and two more on both islands. These include six species of “microgastropods” with wider ranges in tropical Africa that are likely to be hitherto overlooked parts of the indigenous fauna and six anthropogenic introductions. Pseudopeas crossei previously known only from Príncipe and Bioko is newly recorded on São Tomé. More detailed taxonomic notes are provided on identification and delimitation of species and genera in Cyclophoridae/ Maizaniidae, Veronicellidae, Achatinidae, Cerastidae, Helicarionidae, and on the forgotten but apparently valid Pseudoveronicella thomensis (Veronicellidae).info:eu-repo/semantics/publishedVersio

Myocardial tissue tagging with cardiovascular magnetic resonance

Cardiovascular magnetic resonance (CMR) is currently the gold standard for assessing both global and regional myocardial function. New tools for quantifying regional function have been recently developed to characterize early myocardial dysfunction in order to improve the identification and management of individuals at risk for heart failure. Of particular interest is CMR myocardial tagging, a non-invasive technique for assessing regional function that provides a detailed and comprehensive examination of intra-myocardial motion and deformation. Given the current advances in gradient technology, image reconstruction techniques, and data analysis algorithms, CMR myocardial tagging has become the reference modality for evaluating multidimensional strain evolution in the human heart. This review presents an in depth discussion on the current clinical applications of CMR myocardial tagging and the increasingly important role of this technique for assessing subclinical myocardial dysfunction in the setting of a wide variety of myocardial disease processes

Inhibition of human neutrophil oxidative burst by pyrazolone derivatives

The risk of agranulocytosis associated with the use of pyrazolone drugs at therapeutical doses and for short periods of time has been considered to be very low. However, little or no attention at all has been devoted to the possible hindrance of neutrophil burst and scavenging of neutrophilgenerated reactive oxygen species (ROS) by these compounds. Such an effect could be beneficial in the case of overactivation of neutrophils but could also be highly detrimental if the number of circulating neutrophils is already decreased. Thus, the aim of the present study was to evaluate the putative inhibitory effect of the pyrazolones dipyrone, aminopyrine, isopropylantipyrine, and antipyrine against human neutrophil burst and their scavenging activity against O2 S!, H2O2, HOS, ROOS, and HOCl. The obtained results showed that dipyrone and aminopyrine prevent phorbol-12-myristate-13-acetate-induced neutrophil burst with high efficiency, while isopropylantipyrine had little effect and antipyrine had no effect at all. Dipyrone and aminopyrine were highly potent scavengers of HOS and HOCl, while, in accordance with the neutrophil burst results, isopropylantipyrine had little effect and antipyrine had no effect at all against these two ROS. None of the studied pyrazolones was capable of scavenging O2 S! or H2O2, while dipyrone was shown to be the most reactive against ROOS

Listening to Music in the First, but not the Last 1.5 km of a 5-km Running Trial Alters Pacing Strategy and Improves Performance

We examined the effects of listening to music on attentional focus, rating of perceived exertion (RPE), pacing strategy and performance during a simulated 5-km running race. 15 participants performed 2 controlled trials to establish their best baseline time, followed by 2 counterbalanced experimental trials during which they listened to music during the first (M-start) or the last (M-finish) 1.5 km. The mean running velocity during the first 1.5 km was significantly higher in M-start than in the fastest control condition (p < 0.05), but there was no difference in velocity between conditions during the last 1.5 km (p > 0.05). The faster first 1.5 m in M-start was accompanied by a reduction in associative thoughts compared with the fastest control condition. There were no significant differences in RPE between conditions (p > 0.05). These results suggest that listening to music at the beginning of a trial may draw the attentional focus away from internal sensations of fatigue to thoughts about the external environment. However, along with the reduction in associative thoughts and the increase in running velocity while listening to music, the RPE increased linearly and similarly under all conditions, suggesting that the change in velocity throughout the race may be to maintain the same rate of RPE increase.Australian Department of Education, Employment and Workplace RelationsAustralian Department of Education, Employment and Workplace Relation

One-pot hydrogen production and cascade reaction of furfural to bioproducts over bimetallic Pd-Ni TUD-1 type mesoporous catalysts

Bimetallic Pd-Ni TUD-1 type mesoporous catalysts are effective for the cascade reaction of the renewable platform chemical furfural (FUR) to the useful bioproducts 2-alkoxyfuran, 2-methylfuran (2MF), 4-oxopentanal and its acetals, which find diverse applications, some already in the market. With a single catalyst, the in situ hydrogen supply from formic acid (FAc), as well as several acid-reduction steps of the overall catalytic process were triggered, leading to the desired bioproducts (bioPs), all in one-pot under moderate reaction conditions. These multipurpose materials were prepared using different procedures and conditions, which influenced the material properties and the catalytic performances. Detailed characterisation (microstructural/molecular level) and catalytic studies led to new mechanistic insights into the FUR reaction (with identification of intermediates), allowed to assess the roles of the different types of metal species in the complex reaction mechanism, understand the influence of material properties on the catalytic process, and catalyst stability and regeneration. The best-performing catalyst was prepared stepwise via impregnation of palladium on a hydrothermally synthesised nickel silicate with a molar ratio Si/Ni of 20, ending with filtration-washing-calcination procedures. This catalyst led to 83% 2MF yield, at 98% FUR conversion (90% total bioPs yield), using 1-butanol as solvent, at 170 °C. The reported catalytic protocol benefits from the fact that external usage of H2 for catalyst activation and/or the catalytic reaction is not required, no high-pressure gases are used, and FAc is used as source of hydrogen supplied in situ for the catalytic reaction under moderate conditions. Moreover, FAc presents low toxicity, it is easy to handle/store, and is a typical coproduct of carbohydrate biomass conversion processes, and thus its repurposing is highly desirable.publishe

The optical/X-ray connection: ICM iron content and galaxy optical luminosity in 20 galaxy clusters

X-ray observations of galaxy clusters have shown that the intra-cluster gas has iron abundances of about one third of the solar value. These observations also show that part (if not all) of the intra-cluster gas metals were produced within the member galaxies. We present a systematic analysis of 20 galaxy clusters to explore the connection between the iron mass and the total luminosity of early-type and late-type galaxies, and of the brightest cluster galaxies (BCGs). From our results, the intra-cluster medium (ICM) iron mass seems to correlate better with the luminosity of the BCGs than with that of the red and blue galaxy populations. As the BCGs cannot produce alone the observed amount of iron, we suggest that ram-pressure plus tidal stripping act together to enhance, at the same time, the BCG luminosities and the iron mass in the ICM. Through the analysis of the iron yield, we have also estimated that SN Ia are responsible for more than 50% of the total iron in the ICM. This result corroborates the fact that ram-pressure contributes to the gas removal from galaxies to the inta-cluster medium, being very efficient for clusters in the temperature range 2 < kT (keV)< 10Comment: Accepted for publication in MNRAS (11 pg, 9 figures and 3 tables

Spiral-like structure in nearby clusters of galaxies

X-ray data analysis have found that fairly complex structures at cluster centres are more common than expected. Many of these structures have similar morphologies, which exhibit spiral-like substructure. It is not yet well known how these structures formed or are maintained. Understanding the origin of these spiral-like features at the centre of some clusters is the major motivation behind this work. We analyse deep \textit{Chandra} observations of 15 nearby galaxy clusters (0.01 $< z <$ 0.06), and use X-ray temperature and substructure maps to detect small features at the cores of the clusters. We detect spiral-like features at the centre of 7 clusters: A85, A426, A496, Hydra A cluster, Centaurus, Ophiuchus, and A4059. These patterns are similar to those found in numerical hydrodynamic simulations of cluster mergers with non-zero impact parameter. In some clusters of our sample, a strong radio source also occupies the inner region of the cluster, which indicates a possible connection between the two. Our investigation implies that these spiral-like structures may be caused by off-axis minor mergers. Since these features occur in regions of high density, they may confine radio emission from the central galaxy producing, in some cases, unusual radio morphology.Comment: 14 pages, 3 figures, accepted for publication in A&A (Nov 17, 2009