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In this work we report the experimental studies of the structural phase transition in the [(C3H7)4N]SnCl5(H2O)]·2H2O compound by differential scanning calorimetric (DSC) and Raman spectroscopic. The X-ray powder diffraction study of the [(C3H7)4N][SnCl5(H2O)]·2H2O sample at room temperature showed that this compound is monoclinic and has P121/c1 space group. Differential scanning calorimetric disclosed two types of phase transitions in the temperature range 356–376 (T1) K and at 393K (T2) characterized, by a loss of water molecules and probably a reconstruction of new anionic parts after T2 transition. The Raman scattering spectra recorded at various temperatures in the wavenumber range from 100 to 3800cm−1 covering the domains of existence of changes in the vicinity of the two phase transitions detected by DSC measurement. A detailed study of the spectral parameters (wave number, reduced intensity and the full width at half maximum) as a function of temperature of a chosen band, associated with (νs(SnO)+νs(SnCl)), based on an order–disorder model allowed us to obtain information relative to the activation energy and correlation length.
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How early blindness reorganizes the brain circuitry that supports auditory motion processing remains controversial. We used fMRI to characterize brain responses to in-depth, laterally moving, and static sounds in early blind and sighted individuals. Whole-brain univariate analyses revealed that the right posterior middle temporal gyrus and superior occipital gyrus selectively responded to both in-depth and laterally moving sounds only in the blind. These regions overlapped with regions selective for visual motion (hMT+/V5 and V3A) that were independently localized in the sighted. In the early blind, the right planum temporale showed enhanced functional connectivity with right occipito-temporal regions during auditory motion processing and a concomitant reduced functional connectivity with parietal and frontal regions. Whole-brain searchlight multivariate analyses demonstrated higher auditory motion decoding in the right posterior middle temporal gyrus in the blind compared to the sighted, while decoding accuracy was enhanced in the auditory cortex bilaterally in the sighted compared to the blind. Analyses targeting individually defined visual area hMT+/V5 however indicated that auditory motion information could be reliably decoded within this area even in the sighted group. Taken together, the present findings demonstrate that early visual deprivation triggers a large-scale imbalance between auditory and “visual” brain regions that typically support the processing of motion information.
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Species delimitations is problematic in many cases due to the difficulty of evaluating predictions from species hypotheses. In many cases delimitations rely on subjective interpretations of morphological and/or DNA data. Species with inadequate genetic resources needed to answer questions regarding evolutionary relatedness and genetic uniqueness are particularly problematic. In this study, we demonstrate the utility of restriction site associated DNA sequencing (RAD-seq) to objectively resolve unambiguous phylogenetic relationships in a recalcitrant group of deep-sea corals with divergences >80 million years. We infer robust species boundaries in the genus Paragorgia by testing alternative delimitation hypotheses using a Bayes Factors delimitation method. We present substantial evidence rejecting the current morphological species delimitation model for the genus and infer the presence of cryptic species associated with environmental variables. We argue that the suitability limits of RAD-seq for phylogenetic inferences cannot be assessed in terms of absolute time, but are contingent on taxon-specific factors. We show that classical taxonomy can greatly benefit from integrative approaches that provide objective tests to species delimitation hypotheses. Our results lead the way for addressing further questions in marine biogeography, community ecology, population dynamics, conservation, and evolution.
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In the present paper, I attempt to theoretically describe, analyze and compare the structural and optical properties in the core/multi-shell nanocrystal structure of a cadmium selenide (CdSe) core surrounded by zinc selenide (ZnSe) inner and zinc sulphide (ZnS) external growth shells. The atomistic tight-binding model (TB) and a configuration interaction method (CI) are implemented to calculate the single-particle spectra, optical band gaps, ground-state wave function overlaps, ground-state oscillation strengths, ground-state coulomb energies, ground-state exchange energies and Stokes shift as a function of ZnS external growth shell thicknesses. I underline that these computations are principally sensitive with the ZnS external growth shell thickness. The reduction of the optical band gaps, overlaps of ground electron-hole wave function, electron-hole interactions and Stokes shift is realized with the increasing ZnS external growth shell thickness. The improvement of the optical intensities is mainly achieved by including the ZnS exterior growth shell encapsulation. Importantly, the optical band gaps based on atomistic tight-binding theory are in a good agreement with the experiment. Finally, this emphasizes that the external passivation shell can now be engineered in a defined way, thus leading to manipulate the natural behaviors of nanodevices based on the scrutinized core/multi-shell nanocrystals.
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Using data collected for the Environmental Protection Agency's (EPA) 2011 National Wetland Condition Assessment (NWCA), we developed separate multimetric indices (MMIs) for vegetation, soil, algae taxa, and water to assess condition of freshwater wetlands in the northeastern US. This study represents the first attempt at developing multiple biotic and abiotic MMIs of wetland condition over this large of an area, and is only possible because of the high quality data collected by the NWCA. We chose metrics that distinguished between reference and most disturbed sites, had a signal:noise ratio>2, and were not strongly correlated with other metrics, latitude, or longitude. The vegetation and soil MMIs were the best performing indices, with good separation between reference and most disturbed sites, and included commonly used condition metrics (e.g., pH and P concentration for soil, and percent cover of exotic species for vegetation). The algae MMI was the weakest index, with considerable overlap between reference and most disturbed sites. For areas smaller than our study, algae taxa may be suitable for wetland MMIs. However, in our study area, many algae taxa followed strong latitudinal or longitudinal gradients, and could not be considered for the algae MMI. Small sample size and several metrics with a high signal:noise ratio were the major limitations of the water MMI. We also examined how well landscape (level 1) and rapid assessment (level 2) metrics predicted MMIs using random forest regression. Agricultural land use surrounding wetlands was an important predictor for all four MMIs, although the soil, algae and water MMI models performed best when intensive (level 3) vegetation metrics were also included in the random forest regression models. Based on these results, we recommend wetland assessment programs employ a combination of landscape and rapid assessment monitoring at many sites, along with level 3 monitoring at a subset of sites. We developed these MMIs to evaluate freshwater wetland condition for a long-term monitoring program in Acadia National Park. These MMIs are also applicable to a range of wetland types covering 11 states in the northeastern United States and can be calculated using a downloadable spreadsheet that calculates and rates each MMI using raw metric values.
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Intensities and self-broadening coefficients are presented for about 460 of the strongest water vapour lines in the spectral regions 1400–1840cm−1 and 3440–3970cm−1 at room temperature, obtained from rather unique measurements using a 5-mm-path-length cell. The retrieved spectral line parameters are compared with those in the HITRAN database ver. 2008 and 2012 and with recent ab-initio calculations. Both the retrieved intensities and half-widths are on average in reasonable agreement with those in HITRAN-2012. Maximum systematic differences do not exceed 4% for intensities (1600cm−1 band) and 7% for self-broadening coefficients (3600cm−1 band). For many lines however significant disagreements were detected with the HITRAN-2012 data, exceeding the average uncertainty of the retrieval. In addition, water vapour line parameters for 5300cm−1 (1.9μm) band reported by us in 2005 were also compared with HITRAN-2012, and show average differences of 4–5% for both intensities and half-widths.
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Infection with helminthic parasites, including the soil-transmitted helminth Trichuris trichiura (human whipworm), has been shown to modulate host immune responses and, consequently, to have an impact on the development and manifestation of chronic human inflammatory diseases. De novo derivation of helminth proteomes from sequencing of transcriptomes will provide valuable data to aid identification of parasite proteins that could be evaluated as potential immunotherapeutic molecules in near future. Herein, we characterized the transcriptome of the adult stage of the human whipworm T. trichiura, using next-generation sequencing technology and a de novo assembly strategy. Nearly 17.6 million high-quality clean reads were assembled into 6414 contiguous sequences, with an N50 of 1606bp. In total, 5673 protein-encoding sequences were confidentially identified in the T. trichiura adult worm transcriptome; of these, 1013 sequences represent potential newly discovered proteins for the species, most of which presenting orthologs already annotated in the related species T. suis. A number of transcripts representing probable novel non-coding transcripts for the species T. trichiura were also identified. Among the most abundant transcripts, we found sequences that code for proteins involved in lipid transport, such as vitellogenins, and several chitin-binding proteins. Through a cross-species expression analysis of gene orthologs shared by T. trichiura and the closely related parasites T. suis and T. muris it was possible to find twenty-six protein-encoding genes that are consistently highly expressed in the adult stages of the three helminth species. Additionally, twenty transcripts could be identified that code for proteins previously detected by mass spectrometry analysis of protein fractions of the whipworm somatic extract that present immunomodulatory activities. Five of these transcripts were amongst the most highly expressed protein-encoding sequences in the T. trichiura adult worm. Besides, orthologs of proteins demonstrated to have potent immunomodulatory properties in related parasitic helminths were also predicted from the T. trichiura de novo assembled transcriptome.
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Magnesium aluminium hydroxycarbonate hydrotalcites (denoted as MgAl–CO3-HTs) with different Mg/Al molar ratios (4, 3 and 2) were synthesised by the co-precipitation method under low supersaturation conditions, and then treated with sodium dodecylsulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS) surfactants to produce the nanocomposites — organo-hydrotalcites; dodecylsulfate-hydrotalcites(DS-HTs) and dodecylbenzenesulfonate-hydrotalcites (DBS-HTs) through calcination-reconstruction method. Powder X-ray diffraction (PXRD) and infrared spectroscopy analysis of intercalated samples showed that dodecylsulfate and dodecylbenzenesulfonate guests were successfully intercalated into the parent hydrotalcites, with the PXRD revealing that the species could assume varying configurations within the interlayer gallery regions of this clay based materials, displaying monolayer and bilayer orientations.
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Tree stumps left after clear-cutting have replaced naturally formed logs as the most common type of coarse woody debris in managed boreal forests. It is therefore necessary to understand stump importance for the biodiversity of wood-inhabiting organisms, including fungi, and determine their role in hosting species of conservation interest. We analyzed wood from 485 Norway spruce (Picea abies) stumps from 41 clear-cuts at seven localities along a latitudinal gradient from northern to southern Sweden using 454-sequencing. We also collated data about the known ecology of the 86 identified macro-basidiomycetes. In total, 1355 fungal operational taxonomic units were detected, of which 19% were identified down to genus or species level. The most widespread fungi were generalists, such as Leptodontidium elatius, Resinicium bicolor, Fomitopsis pinicola, and Coniophora puteana. Five species of conservation interest were detected, but were not abundant (Kneiffiella curvispora, Metulodontia nivea, Perenniporia subacida, Postia placenta, and Climacocystis borealis). Fungal community composition changed with stump age and along the latitudinal gradient.
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The Central Andean Plateau (15°–27°S) is a high plateau in excess of 3km elevation, associated with thickened crust along the western edge of the South America plate, in the convergent margin between the subducting Nazca plate and the Brazilian craton. We have calculated receiver functions using seismic data from a recent portable deployment of broadband seismometers in the Bolivian orocline (12°–21°S) region and combined them with waveforms from 38 other stations in the region to investigate crustal thickness and crust and mantle structures. Results from the receiver functions provide a more detailed map of crustal thickness than previously existed, and highlight mid-crustal features that match well with prior studies. The active volcanic arc and Altiplano have thick crust with Moho depths increasing from the central Altiplano (65km) to the northern Altiplano (75km). The Eastern Cordillera shows large along strike variations in crustal thickness. Along a densely sampled SW–NE profile through the Bolivian orocline there is a small region of thin crust beneath the high peaks of the Cordillera Real where the average elevations are near 4km, and the Moho depth varies from 55 to 60km, implying the crust is undercompensated by ~5km. In comparison, a broader region of high elevations in the Eastern Cordillera to the southeast near ~20°S has a deeper Moho at ~65–70km and appears close to isostatic equilibrium at the Moho. Assuming the modern-day pattern of high precipitation on the flanks of the Andean plateau existed since the late Miocene, we suggest that climate induced exhumation can explain some of the variations in present day crustal structure across the Bolivian orocline. We also suggest that south of the orocline at ~20°S, the thicker and isostatically compensated crust is due to the absence of erosional exhumation and the occurrence of lithospheric delamination.
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