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Zinc nitrate, 2,4-pyridinedicarboxylic acid (2,4-pdcH2), and a hydrogen-bonding capable dipyridylamide ligand were combined in aqueous solution and subjected to hydrothermal reaction conditions. Three new crystalline coordination complexes were generated; their dimensionality depends crucially on the dipyridylamide length and geometric disposition of the pyridyl nitrogen donors. The three new phases were structurally characterized via single-crystal X-ray diffraction. {[H23-pina][Zn(2,4-pdc)2(H2O)2]·H2O} (1, 3-pina = 3-pyridylisonicotinamide) is a salt with protonated dipyridylamide cations and coordination complex anions. {[Zn2(2,4-pdc)2(H2O)4(3-pna)]·3H2O}n (2, 3-pna = 3-pyridylnicotinamide) shows a system of two-fold interpenetrated ruffled (6,3) coordination polymer layers. {[Zn(2,4-pdc)(H2O)2(3-pmna)]n (3, 3-pmna = 3-pyridylmethylnicotinamide) manifests a simple 1D chain topology. Luminescence was observed for two of the zinc complexes; this behavior is attributed to π–π* or π–n molecular orbital transitions. Thermal decomposition properties of the new phases are also probed.
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The last decade has seen the advent and consolidation of ontology based tools for the identification and biological interpretation of classes of genes, such as the Gene Ontology. The Gene Ontology (GO) is constantly evolving over time. The information accumulated time-by-time and included in the GO is encoded in the definition of terms and in the setting up of semantic relations amongst terms. Here we investigate the Gene Ontology from a complex network perspective. We consider the semantic network of terms naturally associated with the semantic relationships provided by the Gene Ontology consortium. Moreover, the GO is a natural example of bipartite network of terms and genes. Here we are interested in studying the properties of the projected network of terms, i.e. a gene-based weighted network of GO terms, in which a link between any two terms is set if at least one gene is annotated in both terms. One aim of the present paper is to compare the structural properties of the semantic and the gene-based network. The relative importance of terms is very similar in the two networks, but the community structure changes. We show that in some cases GO terms that appear to be distinct from a semantic point of view are instead connected, and appear in the same community when considering their gene content. The identification of such gene-based communities of terms might therefore be the basis of a simple protocol aiming at improving the semantic structure of GO. Information about terms that share large gene content might also be important from a biomedical point of view, as it might reveal how genes over-expressed in a certain term also affect other biological processes, molecular functions and cellular components not directly linked according to GO semantics.
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We present results from a suite of 169 hydrocode simulations of collisions between planetary bodies with radii from 100 to 1000 km. The simulation data are used to derive a simple scaling law for the threshold for catastrophic disruption, defined as a collision that leads to half the total colliding mass escaping the system post impact. For a target radius 100 ≤ RT ≤ 1000km and a mass MT and a projectile radius rp ≤ RT and mass mp we find that a head-on impact with velocity magnitude v is catastrophic if the kinetic energy of the system in the center of mass frame, K=0.5MTmpv2/(MT+mp), exceeds a threshold value K* that is a few times U=(3/5)GMT2/RT+(3/5)Gmp2/rp+GMTmp/(RT+rp), the gravitational binding energy of the system at the moment of impact; G is the gravitational constant. In all head-on collision runs we find K*=(5.5±2.9)U. Oblique impacts are catastrophic when the fraction of kinetic energy contained in the volume of the projectile intersecting the target during impact exceeds ∼2 K* for 30° impacts and ∼3.5 K* for 45° impacts. We compare predictions made with this scaling to those made with existing scaling laws in the literature extrapolated from numerical studies on smaller targets. We find significant divergence between predictions where in general our results suggest a lower threshold for disruption except for highly oblique impacts with rp ≪ RT. This has implications for the efficiency of collisional grinding in the asteroid belt (Morbidelli et al., [2009] Icarus, 204, 558–573), Kuiper belt (Greenstreet et al., [2015] Icarus, 258, 267–288), and early Solar System accretion (Chambers [2013], Icarus, 224, 43–56).
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Variation in the facial width-to-height ratio (fWHR) maps onto a number of behavioral and psychological traits among men (e.g., aggression, unethical behavior, negotiation performance). Importantly, observer judgments of many of these traits also correlate strongly with the fWHR, suggesting that it may represent an honest cue to dominance and status. It has been speculated that the relationship between fWHR and these behavioral traits is due to pubertal testosterone concurrently shaping facial structure and traits linked to social dominance. Others, however, have provided some initial, although inconsistent, evidence that circulating testosterone levels in adulthood may underlie associations between the fWHR and behavioral displays. Here, we provide a more powerful test of the second model by examining the relationship between fWHR, baseline testosterone, and competition-induced testosterone reactivity, across seven diverse samples of men (total N=780). We also report a further analysis including data published previously, for a total sample of 1041 men. Analysis of our individual samples, in addition to an internal meta-analysis, demonstrated no significant positive relationship between fWHR and baseline testosterone, or fWHR and three measures of competition-induced testosterone reactivity. We discuss potential reasons for previous discrepancies, and suggest avenues for future research.
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In robust nonparametric kernel regression context, we prescribe method to select trimming parameter and bandwidth. Through solving estimating equations, we control outlier effect through combining weighting and trimming. We show asymptotic consistency, establish bias, variance properties and derive asymptotics.
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A fundamental challenge to understanding our evolved psychology is to explain how cooperative or prosocial behaviors are maintained despite the immediate temptation to free-ride. We propose that charismatic leadership and followership can be best understood as a product of this recurrent, fitness-relevant selection pressure for adaptations that effectively promoted and sustained prosocial behaviors within groups. We describe charismatic leadership and followership as a dynamic process in which leaders signal their ability to benefit the group by increasing the perceived likelihood that cooperation will succeed. A charismatic leader is one who is able to attract the attention of other group members and serve as a focal point for aligning and synchronizing prosocial orientations in followers, suppressing sensitivity to cooperative risks, and enhancing the salience of perceived cooperative rewards. We hypothesize that exposure to such individuals will activate heuristics causing participants to behave more prosocially. The results of three economic experiments (N=500) provide behavioral evidence for the “charismatic prosociality” hypothesis through the use of the Trust, Dictator, and Stag Hunt Games.
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The insulin-like growth factor 2 antisense (Igf2as) gene is part of the Ins-Igf2-H19 imprinted gene cluster. The function of the paternally expressed Igf2as is still elusive. In our previous work, we showed that Igf2as transcripts were located in the cytoplasm of C2C12 mouse myoblast cells, associated with polysomes and polyadenylated suggesting that Igf2as is protein coding. In the present work, the protein coding capacity of Igf2as was investigated. We demonstrate for the first time the existence of a polypeptide translated from an Igf2as construct. Furthermore, an RNA-Seq analysis was performed using RNA prepared from skeletal muscles of newborn wild-type and ∆DMR1-U2 mice to further elucidate the function of Igf2as transcripts. We found no evidence for a regulatory role of Igf2as in the imprinted gene cluster. Interestingly, the RNA-Seq analysis indicated that Igf2as plays a role in the energy metabolism, the cell cycle, histone acetylation and muscle contraction pathways. Our Igf2as investigations further elucidated that there are two distinct Igf2as transcripts corresponding to two putative ORFs.
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High quality line parameters of the band systems of ethane are required for accurate characterization of spectral features observed in the atmospheres of Jovian planets and their satellites. To date, experimental characterization of the excited vibrational states lying below 1300cm−1 has been made. This includes the torsional bands around 35µm, ν9 (820cm−1), ν3 (990cm−1), ν12−ν9 (380cm−1) and ν9+ν4−ν4 (830cm−1) bands. These earlier high resolution ro-vibrational analyses were made to experimental accuracy. Here, we report a detailed analysis of the weak ν6 band in the 1340–1410cm−1 region using a spectrum recorded at a resolution of 0.003cm−1 and temperature of 200K. The Hamiltonian model included couplings between ν6 and ν9 (in particular with ν9+2ν4 with which it is resonantly coupled) as well as couplings between ν6 and ν8. An excellent fit to within experimental accuracy was obtained. Taking the results of this 5-state fit, together with earlier results on lower lying vibrations, we now have experimental characterization for torsion–vibration states of ethane lying below 1400cm−1.
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Skeletal muscle, cartilage and bone must function in a co-ordinated fashion during locomotion and growth. In the present study on the gilthead sea bream (Sparus aurata) we tested the hypothesis that muscle and bone differ in their responsiveness to stimuli eliciting fast growth, providing a potential mechanism for generating the skeletal deformities observed in aquaculture. To investigate transcription regulation in skeletal muscle and bone we stimulated protein synthesis using a flooding dose of the branched chain amino acid leucine and compared the results with saline-injected controls. To increase the amount of available sequence information for gene expression analysis a de novo transcriptome was assembled using publicly available Next Generation Sequencing libraries from embryo, fast skeletal muscle, bone and cartilage. The resulting 5 million reads were assembled into 125,646 isotigs representing around 16,000 unique genes, including most components of the Pi3k/Akt/mTor signalling pathway. Principal components analysis was able to distinguish the transcriptional responses between leucine and saline injected controls in skeletal muscle, but not in the bone. General Linear Modelling revealed significant temporal changes in gene expression following leucine injection including the tissue-specific markers sparc, bglap (bone), mlc2 and myod2 (muscle) and gene transcripts associated with Pi3k/Akt/mTor signalling, p70sk6, akt2, ampka and mtor. Skeletal muscle showed more pronounced and rapid changes in transcript abundance than the bone to the same pro-growth signal. The observed differences in transcriptional response are consistent with the idea that fast growth results in a miss-match between muscle and bone development and may contribute to a higher incidence of skeletal deformities.
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Genome-scale metabolic models comprise stoichiometric relations between metabolites, as well as associations between genes and metabolic reactions and facilitate the analysis of metabolism. We computationally reconstructed the metabolic network of the lactic acid bacterium Streptococcus pyogenes M49. Initially, we based the reconstruction on genome annotations and already existing and curated metabolic networks of Bacillus subtilis, Escherichia coli, Lactobacillus plantarum and Lactococcus lactis. This initial draft was manually curated with the final reconstruction accounting for 480 genes associated with 576 reactions and 558 metabolites. In order to constrain the model further, we performed growth experiments of wild type and arcA deletion strains of S. pyogenes M49 in a chemically defined medium and calculated nutrient uptake and production fluxes. We additionally performed amino acid auxotrophy experiments to test the consistency of the model. The established genome-scale model can be used to understand the growth requirements of the human pathogen S. pyogenes and define optimal and suboptimal conditions, but also to describe differences and similarities between S. pyogenes and related lactic acid bacteria such as L. lactis in order to find strategies to reduce the growth of the pathogen and propose drug targets.
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