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The torsional and rotation–torsion spectra of the doubly deuterated species of methanol CD2HOH have been analyzed using submillimeter wave, terahertz, and far infrared spectra. 101 torsional subbands, with subband centers ranging from 2.3 to 626cm−1, were assigned. Analysis of these yielded kinetic energy and hindering potential parameters of the torsional Hamiltonian describing the large amplitude internal rotation of the CD2H methyl group with respect to the hydroxyl group. 3271 rotation and rotation–torsion transitions, involving the 24 torsional levels up to e1 with 3⩽K⩽10, were assigned and fitted approximating the rotational energy of each torsional level with a Taylor-type expansion in J(J+1). The rotational structure of 48 torsional subbands involving torsional levels higher than e1 has also been analyzed. In most cases, only the Q branch could be observed and assigned.
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The 13CH4 absorption spectrum has been recorded at 296K and 80K in the Icosad range between 6600 and 7700cm−1. The achieved noise equivalent absorption of the spectra recorded by differential absorption spectroscopy (DAS) is about αmin≈1.5×10−7cm−1. Two empirical line lists were constructed including 17,792 and 24,139 lines at 80K and 296K, respectively. For comparison, the HITRAN database provides only 1040 13CH4 lines in the region determined from methane spectra with natural isotopic abundance. Empirical values of the lower state energy level, Eemp, were systematically derived from the intensity ratios of the lines measured at 80K and 296K. Overall 10,792 Eemp values were determined providing accurate temperature dependence for most of the 13CH4 absorption in the region (93% and 82% at 80K and 296K, respectively). The quality of the derived empirical values of the lower state rotational quantum number, Jemp, is illustrated by their clear propensity to be close to an integer. A good agreement is achieved between our small Jemp values, with previous accurate determinations obtained by applying the 2T method to jet and 80K spectra. The line lists at 296K and 80K which are provided as Supplementary material will be used for future rovibrational assignments based on accurate variational calculations.
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Ovarian carcinoma is the fifth-leading cause of cancer death among women in the United States. Major reasons for this persistent mortality include the poor understanding of the underlying biology and a lack of reliable biomarkers. Previous studies have shown that aberrantly expressed MicroRNAs (miRNAs) are involved in carcinogenesis and tumor progression by post-transcriptionally regulating gene expression. However, the interference of miRNAs in tumorigenesis is quite complicated and far from being fully understood. In this work, by an integrative analysis of mRNA expression, miRNA expression and clinical data published by The Cancer Genome Atlas (TCGA), we studied the modularity and dynamicity of miRNA–mRNA interactions and the prognostic implications in high-grade serous ovarian carcinomas. With the top transcriptional correlations (Bonferroni-adjusted p-value<0.01) as inputs, we identified five miRNA–mRNA module pairs (MPs), each of which included one positive-connection (correlation) module and one negative-connection (correlation) module. The number of miRNAs or mRNAs in each module varied from 3 to 7 or from 2 to 873. Among the four major negative-connection modules, three fit well with the widely accepted miRNA-mediated post-transcriptional regulation theory. These modules were enriched with the genes relevant to cell cycle and immune response. Moreover, we proposed two novel algorithms to reveal the group or sample specific dynamic regulations between these two RNA classes. The obtained miRNA–mRNA dynamic network contains 3350 interactions captured across different cancer progression stages or tumor grades. We found that those dynamic interactions tended to concentrate on a few miRNAs (e.g. miRNA-936), and were more likely present on the miRNA–mRNA pairs outside the discovered modules. In addition, we also pinpointed a robust prognostic signature consisting of 56 modular protein-coding genes, whose co-expression patterns were predictive for the survival time of ovarian cancer patients in multiple independent cohorts.
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Paleoecological and faunal-based paleoenvironmental studies rely on fossil assemblages that have high fidelity to the once-living faunas and to the target environment. However, many sedimentary records contain multiple depositional facies, transported sediments with their associated fossils, and varying degrees of taphonomic alteration, which can confound interpretations. Here we combine measures of compositional fidelity, modern analog faunal methods, sedimentary analyses, and taphonomic scoring to examine the history of sediment transport and environmental change in a ~60,000year continental slope record from the Gulf of Alaska using benthic foraminiferal assemblages. These assemblages generally have good compositional fidelity to modern faunas in the Gulf of Alaska, but are not necessarily faithful to the modern continental slope. Fossil benthic foraminiferal assemblages with modern analogs from shelf and slope environments are intercalated downcore suggesting episodes of sedimentary transport to the slope site. Fossil assemblages without modern analogs in this record appear ecologically, rather than taphonomically, derived and thus suggest that the range of past environmental variation in the Gulf of Alaska is not captured by modern spatial variation. These no-analog fossil assemblages are allied with analog assemblages using similarity in taxonomic and sedimentary characteristics, permitting analysis of environmental change in shelf and slope settings from a single core. The faunal composition of the no-analog assemblages suggests the Gulf of Alaska slope experienced lower oxygen conditions in the past than observed in the modern gulf. Lower productivity is also suggested for some shelf samples, however geochemical proxy data are necessary to fully interpret the no-analog assemblages.
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This work develops guidance and tools to understand the performance, improve the design, and simplify the evaluation of naturally ventilated low-rise commercial buildings in warm and hot climates. We conducted ∼50,000 detailed energy and airflow simulations in 427 locations across Brazil, varying 55 parameters representing building morphology, fenestration, construction properties, internal gains, operating times, wind modifiers, flowpaths, window control, and soil traits. Comfort performance was quantified by the average annual fraction of occupied hours that exceeded the upper limit of an adaptive comfort zone, and investigated with sensitivity analysis and machine learning methods. Results indicated that, after climate, building size (both footprint area and number of stories) and internal gains were most influential and were positively associated with discomfort. Adding air movement with ceiling fans and providing for night ventilation both proved highly effective comfort interventions. Except for roof solar absorptance, opaque envelope changes, including increasing insulation or thermal mass, had only marginal impacts. A support vector regression metamodel, requiring 29 easily obtainable inputs plus a weather file, was fit to the simulation results and successfully validated (R2=0.97). The metamodel was developed as a simplified compliance path for naturally ventilated buildings to enhance Brazil’s commercial building performance labeling program, which, because it currently provides such a path only for air conditioned buildings, may discouraging decision-makers from considering even more efficient passive solutions. We use a case study to show how the metamodel, which we will distribute publicly, can also serve as a design tool, and demonstrate that modifying a small set of parameters can drastically improve thermal performance and achieve sustainable comfort in hot and warm climates.
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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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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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