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Three different conducting polymers, polythiophene (PT), polypirrol (PPY) and polyaniline (PANI) have been synthesized via oxidative chemical polymerization in aqueous media, in such a way that the synthesis protocol did not involve any toxic solvents. They have been tested in the abatement of nitrates from an aqueous solution without the need of any metal catalyst. The N -containing polymers (PANI and PPy) were able to remove nitrates to a level that accomplishes the European legislation requirements; however, the nature of each polymer greatly influenced the process mechanism. Whereas ion exchange between Cl − and SO 4 2 − counter-ions in the polymer and NO 3 − from water is the main responsible for the effective nitrate removal in PANI, as assessed by FTIR and XPS analyses, the nitrate removal mechanism on PPy is based in an electron transfer from the polymer to nitrate through N sites located in the pyrrolic ring. On the other hand, PT was not able to exchange nitrate unless it was synthesized with FeCl 3 as oxidant/dopant and an anionic surfactant (sodium dodecyl sulfate -SDS-) is used. In that case, the electrostatic attraction between sulfate (OSO 3 − ) groups from the surfactant and Fe 3+ ions from FeCl 3 produced the anchoring of Cl − to the oxidized PT growing chain, this favoring ion exchange with nitrate in the aqueous solution, followed by a redox process. [ABSTRACT FROM AUTHOR]

Abstract: Molecular dynamics (MD) has been shown to be a useful tool for unveiling many aspects of pore formation in lipid membranes under the influence of an applied electric field. However, the study of the structure and transport properties of electropores by means of MD has been hampered by difficulties in the maintenance of a stable electropore in the typically small simulated membrane patches. We describe a new simulation scheme in which an initially larger porating field is systematically reduced after pore formation to lower stabilizing values to produce stable, size-controlled electropores, which can then be characterized at the molecular level. A new method allows the three-dimensional modeling of the irregular shape of the pores obtained as well as the quantification of its volume. The size of the pore is a function of the value of the stabilizing field. At lower fields the pore disappears and the membrane recovers its normal shape, although in some cases long-lived, fragmented pores containing unusual lipid orientations in the bilayer are observed. [Copyright &y& Elsevier]

Abstract: In this work, we investigate if broadly used methodologies are adequate to detect periods of aridity based on the Spanish fossil record and try to infer which of them were more or less severe. Thus, we present a qualitative statistical approach to two popular palaeoecological methodologies: ecological diversity and cenograms. Discriminant models, derived from modern localities of known biome, determined the probable biomes of Neogene–Quaternary fossil assemblages. Principal component analyses (PCA) provided additional inference on their ordination within an aridity gradient. While models work adequately with modern faunas, the analyses of the palaeocommunities showed that their ecological structure is very different from that of modern faunas, affecting the models’ performance. Nevertheless, the PCA was able to establish an aridity gradient. Our results suggest that independent tools of palaeoecological analysis are critical when reconstructing palaeoenvironments. [Copyright &y& Elsevier]

Nitric oxide (NO) is an important modulator involved in immune regulation. Here, we describe conditions under which NO-donors induce apoptosis on Nb2 lymphoma cells, as evidenced by decreased cell viability and increased hypodiploid DNA content determined by flow cytometry. In addition, DNA fragmentation typical of apoptosis was shown by agarose gel electrophoresis. This apoptosis was accompanied by a significant increase of caspase-3-like enzymatic activity. Both ovine prolactin (oPRL) and ovine placental lactogen (oPL) exerted a protective effect on the NO-donor-induced apoptosis. Furthermore, dexamethasone (Dex)-induced cell death was also associated with caspase-3-like activity and oPL had the same potency as oPRL in its protective effect on Dex-induced apoptosis of Nb2 cells. [Copyright &y& Elsevier]

We present a family of algorithms for the numerical approximation of the Schrödinger equation with potential concentrated at a finite set of points. Our methods belong to the so-called fast and oblivious convolution quadrature algorithms. These algorithms are special implementations of Lubich's Convolution Quadrature which allow, for certain applications in particular parabolic problems, to significantly reduce the computational cost and memory requirements. Recently it has been noticed that their use can be extended to some hyperbolic problems. Here we propose a new family of such efficient algorithms tailored to the features of the Green's function for Schrödinger equations. In this way, we are able to keep the computational cost and the storage requirements significantly below existing approaches. These features allow us to perform reliable numerical simulations for longer times even in cases where the solution becomes highly oscillatory or seems to develop finite time blow-up. We illustrate our new algorithm with several numerical experiments. • Convolution quadrature for integral formulations of the Schrödinger equation. • Extension of the fast and oblivious algorithm. • New representation of convolution weights. • Extensive numerical experiments with link to codes. • The quantum beating phenomenon. [ABSTRACT FROM AUTHOR]

Given trigonometric monomials A 1 , A 2 , A 3 , A 4 , such that A 1 , A 3 have the same signs as sin ⁡ t , and A 2 , A 4 the same signs as cos ⁡ t , and natural numbers n , m > 1 , we study the family of Abel equations x ′ = ( a 1 A 1 ( t ) + a 2 A 2 ( t ) ) x m + ( a 3 A 3 ( t ) + a 4 A 4 ( t ) ) x n , a 1 , a 2 , a 3 , a 4 ∈ R . The center variety is the set of values a 1 , a 2 , a 3 , a 4 such that the Abel equation has a center (every bounded solution is periodic). We prove that the codimension of the center variety is one or two. Moreover, it is one if and only if A 1 = A 3 and A 2 = A 4 and it is two if and only if the family has non-trivial limit cycles (different from x ( t ) ≡ 0 ) for some values of the parameters. [ABSTRACT FROM AUTHOR]

Melatonin supplements are used widely in Europe and the United States (US) to alleviate jet-lag and other sleep-delay disorders. Recently, the European Commission authorized two health claims for food containing melatonin, with a minimum dose per quantified portion. This study aimed to determine the dose of melatonin in food supplements marketed in Europe (Spain) and the US by validating a liquid chromatography method with diode array detection (LC-DAD). Additionally, contaminants present in melatonin supplements were analyzed using ultra-high-performance liquid chromatography coupled to an orbitrap mass spectrometer. We tentatively identified 8 tryptophan-related contaminants in melatonin supplements, suggesting tighter impurity control in melatonin supplements is necessary. The LC-DAD validated method achieved reliable results regarding recovery, precision, repeatability, limit of detection, limit of quantitation and linearity. Label melatonin dose varied from 1–1.95 mg/unit and 0.3–5 mg/unit for supplements marketed in Europe (Spain) and the US, respectively. Four out of seventeen supplements showed significant deviations from melatonin content declared on the label (from −60% to −20%). Regarding health claims, three out of the ten supplements purchased in Spain should not include the claim “reduction of time taken to fall asleep”, as their melatonin content is lower than 1 mg. [ABSTRACT FROM AUTHOR]

Fumitories (subfamily Fumarioideae, Papaveraceae) represent, by their wide mainly northern temperate distribution (also present in South Africa) a suitable plant group to use as a model system for studying biogeographical links between floristic regions of the Northern Hemisphere and also the Southern Hemisphere Cape region. However, the phylogeny of the entire Fumarioideae subfamily is not totally known. In this work, we infer a molecular phylogeny of Fumarioideae, which we use to interpret the biogeographical patterns in the subfamily and to establish biogeographical links between floristic regions, such as those suggested by its different inter- and intra-continental disjunctions. The tribe Hypecoeae is the sister group of tribe Fumarieae, this latter holding a basal grade of monotypic or few-species genera with bisymmetric flowers, and a core group, Core Fumarieae, of more specious rich genera with zygomorphic flowers. The biogeographical analysis shows a subfamily that originated in East Asia at the end of the Early Cretaceous. From here, ancestral range expansions followed three different directions, one at the beginning of the Late Cretaceous by the ancestor of tribe Hypecoeae towards central Asia, and two during the Cretaceous–Palaeogene transition towards western North America and Indochina by the ancestor of the tribe Fumarieae. The ancestor of Core Fumarieae expanded its range from East Asia into the Himalayas before to the middle Eocene. The uplifts of the Qinghai-Tibetan Plateau together with the zonal climate pattern of the Palaeogene are suggested to be responsible both for the accelerated diversification rate resulting in the origin of the basal lineages of Core Fumarieae as well as for the westward migration of the ancestor of Fumarieae s.str. into the Irano-Turanian region. From here, this latter group reached South Africa during late Eocene and Mediterranean basin during Oligocene. There were two colonization waves of the Mediterranean following two different routes: a northern route during the early Oligocene by the subtribe Sarcocapninae, probably facilitated by the land bridge resulting of the Mediterranean microplate accretion; and a southern route into North Africa, through the Gomphotherium land bridge, taken by the subtribe Fumariinae between late Oligocene and middle Miocene. [ABSTRACT FROM AUTHOR]

Consider the scalar differential equation x ′ = ∑ i = 0 m a i ( t ) x n i , where a i ( t ) are T -periodic analytic functions, and 1 ≤ n i ≤ n . For any polynomial Q ( x ) = x n 0 − ∑ i = 1 m α i x n i , the equation can be written as x ′ = a 0 Q ( x ) + R ( t , x ) . Let W be the Wronskian of Q and R with respect to x , and Q ˜ , W ˜ the previous polynomials after removing multiplicity of roots and solutions of the differential equation. We prove that if the vector field defined by the differential equation is “transversal” at every point of Q ˜ ( x ) = 0 or W ˜ ( t , x ) = 0 then the number of limit cycles (isolated periodic solutions in the set of periodic solutions) of the differential equation is at most 3 n − 1 . [ABSTRACT FROM AUTHOR]

Abstract: We study the uniqueness of limit cycles (periodic solutions that are isolated in the set of periodic solutions) in the scalar ODE in terms of , , . Our main result characterizes, under some additional hypotheses, the exponents , , , such that for any choice of the equation has at most one limit cycle. The obtained results have direct application to rigid planar vector fields, thus, planar systems of the form , , where . Concretely, when the set has at least three elements (or exactly one) and another technical condition is satisfied, we characterize the exponents , such that the origin of the rigid system is a center for any choice of and also when there are no limit cycles surrounding the origin for any choice of . [Copyright &y& Elsevier]

Abstract: Transgenic mice overexpressing Dyrk1A (TgDyrk1A), a Down syndrome (DS) candidate gene, exhibit motor and cognitive alterations similar to those observed in DS individuals. To gain new insights into the molecular consequences of Dyrk1A overexpression underlying TgDyrk1A and possibly DS motor phenotypes, microarray studies were performed. Transcriptome analysis showed an upregulation of the NR2A subunit of the NMDA type of glutamate receptors in TgDyrk1A cerebellum. NR2A protein overexpression was also detected in TgDyrk1A cerebellar homogenates, in the synaptosome-enriched fraction and in TgDyrk1A primary cerebellar granular neuronal cultures (CGNs). In TgDyrk1A synaptosomes, calcium-imaging experiments showed a higher calcium uptake after NMDA stimulation. Similarly, NMDA administration promoted longer calcium transients in TgDyrk1A CGNs. Taken together, these results show that NMDA-induced calcium rise is altered in TgDyrk1A cerebellar neurons and indicate that calcium signaling is dysregulated in TgDyrk1A mice cerebella. These findings suggest that DYRK1A overexpression might contribute to the dysbalance in the excitatory transmission found in the cerebellum of DS individuals and DS mouse models. [Copyright &y& Elsevier]

The potential of using trisodium phosphate (TSP) and sodium hydroxide (NaOH) to reduce Listeria monocytogenes populations in chicken skin was studied. Raw chicken legs inoculated with L. monocytogenes were dipped in water (control), in 8% (pH=12·59), 10% (pH=12·68) and 12% (pH=12·75) (w/v) TSP solutions, or in NaOH solutions of equal pH values to those of TSP: 0·175%, 0·200% and 0·220% (w/v). Surface pH values and L. monocytogenes counts of chicken skin were determined immediately after treatment (day 0) and after 1, 3 and 5 days of storage at 2°C. Compared with water dipping, TSP and NaOH treatments significantly (P<0·05) reduce Listeria populations at days 0, 1, 3 and 5 of refrigerated storage. Bacterial reductions varied between 1·12 and 3·34 log10 cycles for TSP-treated samples and between 1·80 and 3·28 log10 cycles for NaOH treated samples. The observed reductions in all treated samples were significantly (P<0·05) greater following storage. The concentration of the TSP solution was a significant factor in reducing the populations of L. monocytogenes. However, bacterial reductions were similar in samples treated with different concentrations of NaOH. The TSP or NaOH treatments resulted in relatively high residual surface pH values (8–9) initially and throughout storage. The pH values were significantly higher in the samples treated with TSP than in those treated with NaOH. [Copyright &y& Elsevier]

New criteria are established for upper bounds on the number of limit cycles of periodic Abel differential equations having two periodic invariant curves, one of them bounded. The criteria are applied to obtain upper bounds of either zero or one limit cycle for planar differential systems. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the existence of limit cycles for a family of generalized Abel equations x ′ = A (t) x m + B (t) x n , m , n ≥ 2. Under certain assumptions, it is proved that there exists a non-trivial limit cycle. This limit cycle has the characteristic that it arises from neither a Hopf bifurcation nor a perturbation of periodic orbits in a period annulus around the centre at the origin. [ABSTRACT FROM AUTHOR]

Laccase enzymes (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) play a major role in the degradation of phenolic compounds such as lignin. They are common in fungi and have been suggested to participate in host colonization by pathogenic fungi. Putative mycoviruses have recently been isolated from the causal agent of pine pitch canker disease, Fusarium circinatum Nirenberg & O'Donell. In this study, the effects of single and double mycoviral infections on laccase activity, growth rate and pathogenicity were investigated in fourteen F. circinatum strains. Extracellular laccase activity was analyzed by the Bavendamm test, image processing and a spectrophotometric method. Mycelial growth, in vivo pathogenicity and seedling survival probability were also determined in Monterrey pine ( Pinus radiata D. Don) seedlings. The findings showed that (i) mycelial growth of isolates from the same fungal population was homogeneous, (ii) the presence of mycovirus appears to increase the virulence of fungal isolates, (iii) co-infection (with two mycoviruses) caused cryptic effects in fungal isolates, and (iv) laccases embody a possible auxiliary tool in fungal infection. The prospects for biocontrol, the adaptive role of F . circinatum mycoviruses and the importance of laccase enzymes in host colonization are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The INhibitor of Growth (ING) family of tumor suppressors regulates the transcriptional state of chromatin by recruiting remodeling complexes to sites with histone H3 trimethylated at position K4 (H3K4me3). This modification is recognized by the plant homeodomain (PHD) present at the C-terminus in the five members of the ING family. ING4 facilitates histone H3 acetylation by the HBO1 complex. Here, we show that ING4 forms homodimers through its N-terminal domain, which folds independently into an elongated coiled-coil structure. The central region of ING4, which contains the nuclear localization sequence, is disordered and flexible and does not directly interact with p53, or does it with very low affinity, in contrast to previous findings. The NMR analysis of the full-length protein reveals that the two PHD fingers of the dimer are chemically equivalent and independent of the rest of the molecule. The detailed NMR analysis of the full-length dimeric protein binding to histone H3K4me3 shows essentially the same binding site and affinity as the isolated PHD finger. Therefore, the ING4 dimer has two identical and independent binding sites for H3K4me3 tails, which, in the context of the chromatin, could belong to the same or to different nucleosomes. These results show that ING4 is a bivalent reader of the chromatin H3K4me3 modification and suggest a mechanism for enhanced targeting of the HBO1 complex to specific chromatin sites. This mechanism could be common to other ING-containing remodeling complexes. [Copyright &y& Elsevier]

Abstract: Cyclosporin A (CsA) has nephrotoxic effects known to involve reactive oxygen species (ROS), since antioxidants prevent the kidney damage induced by this drug. Given that mitochondria are among the main sources of intracellular ROS, the aims of our study were to examine the mitochondrial effects of CsA in the porcine renal endothelial cell line LLC-PK1 and the influence of the antioxidant Vitamin E (Vit E). Following the treatment of LLC-PK1 cells with CsA, we assessed the mitochondrial synthesis of superoxide anion, permeability transition pore opening, mitochondrial membrane potential, cardiolipin peroxidation, cytochrome c release and cellular apoptosis, using flow cytometry and confocal microscopy procedures. Similar experiments were done after Vit E preincubation of cells. CsA treatment increased superoxide anion in a dose-dependent way. CsA opened the permeability transition pores, caused Bax migration to mitochondria, and decreased mitochondrial membrane potential and cardiolipin content. Also CsA released cytochrome c into cytosol and provoked cellular apoptosis. Vit E pretreatment inhibited the effects that CsA induced on mitochondrial structure and function in LLC-PK1 cells and avoided apoptosis. CsA modifies mitochondrial LLC-PK1 cell physiology with loss of negative electrochemical gradient across the inner mitochondrial membrane and increased lipid peroxidation. These features are related to apoptosis and can explain the cellular damage that CsA induces. As Vit E inhibited these effects, our results suggest that they were mediated by an increase in ROS production by mitochondria. [Copyright &y& Elsevier]

Food cravings are subjective, motivational states thought to induce binge eating among eating disorder patients. This study compared food cravings across eating disorders. Women (N=135) diagnosed with anorexia nervosa, restrictive (ANR) or binge-purging (ANBP) types, or bulimia nervosa, non-purging (BNNP) or purging (BNP) types completed measures of food cravings. Discriminant analysis yielded two statistically significant functions. The first function differentiated between all the four group pairs except ANBP and BNNP, with levels of various food-craving dimensions successively increasing for ANR, ANBP, BNNP, and BNP participants. The second function differentiated between ANBP and BNNP participants. Overall, the functions improved classification accuracy above chance level (44% fewer errors). The findings suggest that cravings are more strongly associated with loss of control over eating than with dietary restraint tendencies. [ABSTRACT FROM AUTHOR]

Abstract: Food cravings are subjective, motivational states thought to induce binge eating among eating disorder patients. This study compared food cravings across eating disorders. Women (N =135) diagnosed with anorexia nervosa, restrictive (ANR) or binge–purging (ANBP) types, or bulimia nervosa, non-purging (BNNP) or purging (BNP) types completed measures of food cravings. Discriminant analysis yielded two statistically significant functions. The first function differentiated between all the four group pairs except ANBP and BNNP, with levels of various food-craving dimensions successively increasing for ANR, ANBP, BNNP, and BNP participants. The second function differentiated between ANBP and BNNP participants. Overall, the functions improved classification accuracy above chance level (44% fewer errors). The findings suggest that cravings are more strongly associated with loss of control over eating than with dietary restraint tendencies. [Copyright &y& Elsevier]

Abstract: Cluster computing has become an essential issue for designing immersive visualization systems. This paradigm employs scalable clusters of commodity computers with much lower costs than would be possible with the high-end, shared memory computers that have been traditionally used for virtual reality purposes. This change in the design of virtual reality systems has caused some development environments oriented toward shared memory computing to require modifications to their internal architectures in order to support cluster computing. This is the case of VR Juggler, which is considered one of the most important virtual reality application development frameworks based on open source code. This paper not only describes in detail the mechanisms based on cluster computing included in the internal design of VR Juggler, but also proposes a new global performance evaluation methodology. The goal of this methodology is to test the graphical performance of immersive visualization systems based on clusters of computers in terms of both network latency and number of nodes in the cluster. In this sense, a performance evaluation of VR Juggler, both in an overall and a modular approach, is presented. The obtained results show that VR Juggler can be considered as an efficient tool to support immersive visualization systems on a cluster of computers. [Copyright &y& Elsevier]

Abstract: Bacteriophage infections of starter lactic acid bacteria are a serious risk in the dairy industry. Phage infection can lead to slow lactic acid production or even the total failure of fermentation. The associated economic losses can be substantial. Rapid and sensitive methods are therefore required to detect and identify phages at all stages of the manufacture of fermented dairy products. This study describes a simple and rapid multiplex PCR method that, in a single reaction, detects the presence of bacteriophages infecting Streptococcus thermophilus and Lactobacillus delbrueckii, plus three genetically distinct ‘species’ of Lactococcus lactis phages commonly found in dairy plants (P335, 936 and c2). Available bacteriophage genome sequences were examined and the conserved regions used to design five pairs of primers, one for each of the above bacteriophage species. These primers were designed to generate specific fragments of different size depending on the species. Since this method can detect the above phages in untreated milk and can be easily incorporated into dairy industry routines, it might be readily used to earmark contaminated milk for use in processes that do not involve susceptible starter organisms or for use in those that involve phage-deactivating conditions. [Copyright &y& Elsevier]

Abstract: We present the first redundant detection of sporadic impact flashes on the Moon from a systematic survey performed between 2001 and 2004. Our wide-field lunar monitoring allows us to estimate the impact rate of large meteoroids on the Moon as a function of the luminous energy received on Earth. It also shows that some historical well-documented mysterious lunar events fit in a clear impact context. Using these data and traditional values of the luminous efficiency for this kind of event we obtain that the impact rate on Earth of large meteoroids (0.1–10 m) would be at least one order of magnitude larger than currently thought. This discrepancy indicates that the luminous efficiency of the hypervelocity impacts is higher than 10−2, much larger than the common belief, or the latest impact fluxes are somewhat too low, or, most likely, a combination of both. Our nominal analysis implies that on Earth, collisions of bodies with masses larger than 1 kg can be as frequent as 80,000 per year and blasts larger than 15-kton could be as frequent as one per year, but this is highly dependent on the exact choice of the luminous efficiency value. As a direct application of our results, we expect that the impact flash of the SMART-1 spacecraft should be detectable from Earth with medium-sized telescopes. [Copyright &y& Elsevier]