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Linking variation in intrinsic water-use efficiency to isohydricity: a comparison at multiple spatiotemporal scales
No full textSpecies-specific responses of plant intrinsic water-use efficiency (iWUE) to multiple environmental drivers associated with climate change, including soil moisture (), vapor pressure deficit (), and atmospheric CO concentration (), are poorly understood. We assessed how the iWUE and growth of several species of deciduous trees that span a gradient of isohydric to anisohydric water-use strategies respond to key environmental drivers (, and ). iWUE was calculated for individual tree species using leaf-level gas exchange and tree-ring C in wood measurements, and for the whole forest using the eddy covariance method. The iWUE of the isohydric species was generally more sensitive to environmental change than the anisohydric species was, and increased significantly with rising during the periods of water stress. At longer timescales, the influence of was pronounced for isohydric tulip poplar but not for others. Trees’ physiological responses to changing environmental drivers can be interpreted differently depending on the observational scale. Care should be also taken in interpreting observed or modeled trends in iWUE that do not explicitly account for the influence of
Evaluation of an Entrepreneurship Education Intervention for American Indian Adolescents: Trial Design and Baseline Sample Characteristics
No full textEntrepreneurship education is a strength-based approach and holds promise for promoting health equity for American Indian youth. Arrowhead Business Group (ABG) was developed by a tribal-academic research partnership and is being rigorously evaluated for impacts on psychosocial, behavioral, educational, and economic outcomes. This article describes: 1) the trial design and conceptual model under-girding the ABG program; 2) the sociodemographic, sociocultural, and family/household characteristics of participants at baseline; and 3) the baseline differences in key outcome indicators between study groups. Results demonstrate participants have baseline characteristics appropriate for study aims and are compared and contrasted with other youth from the participating tribal community and state in which the tribe resides. Findings inform future analyses to explore how baseline characteristics are associated with primary and secondary outcomes of the evaluation
Observation of the leptonic decay
No full textWe report the first observation of with a significance of 5.1. We measure . Taking the world average , we obtain , which is consistent with the Standard Model expectation of lepton flavor universality. Using external inputs, our results give values for the decay constant and the CKM matrix element that are consistent with, but less precise than, other determinations
Study of the process via initial state radiation at BESIII
No full textThe Born cross section for the process is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an integrated luminosity of 7.5 fb, collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process and the proton effective form factor are determined in the invariant mass range between 2.0 and 3.8 GeV/ divided into 30 intervals. The proton form factor ratio () is measured in 3 intervals of the invariant mass between 2.0 and 3.0 GeV/
Apn2 resolves blocked 3' ends and suppresses Top1-induced mutagenesis at genomic rNMP sites
No full textRibonucleoside monophosphates (rNMPs) mis-incorporated during DNA replication are removed by RNase H2-dependent excision repair or by topoisomerase I (Top1)-catalyzed cleavage. The cleavage of rNMPs by Top1 produces 3′ ends harboring terminal adducts, such as 2′,3′-cyclic phosphate or Top1 cleavage complex (Top1cc), and leads to frequent mutagenesis and DNA damage checkpoint induction. We surveyed a range of candidate enzymes from Saccharomyces cerevisiae for potential roles in Top1-dependent genomic rNMP removal. Genetic and biochemical analyses reveal that Apn2 resolves phosphotyrosine–DNA conjugates, terminal 2′,3′-cyclic phosphates, and their hydrolyzed products. APN2 also suppresses 2-base pair (bp) slippage mutagenesis in RNH201-deficient cells. Our results define additional activities of Apn2 in resolving a wide range of 3′ end blocks and identify a role for Apn2 in maintaining genome integrity during rNMP repair
Limited utility of detailed e-cigarette use measures: An analysis of NESARC-III
No full textIntroduction: The heterogeneity of e-cigarette products and e-liquids pose challenges to surveillance of e-cigarette exposure. The goal of this study was to evaluate the internal consistency of e-cigarette use frequency, quantity, and duration measures in a national population-based survey. Methods: Data were drawn from the 2012–2013 for the National Epidemiologic Survey on Alcohol and Related Conditions-III (n = 36,309; NESARC-III). Adults who used e-cigarettes/e-liquid during the past year (≤18 years old; n = 1,229) were asked about their age of first use, recency of use, quantity (i.e., cartridges, drops), nicotine concentration, and duration (hours). Several internal consistency parameters were compared for e-cigarette measures in past-year (n = 750) and past 30-day e-cigarette users (n = 472) overall, and by frequency of use (i.e., infrequent [≤3 days/month], non-daily [1–6 days/week], daily). Results: There were no significant differences in quantity, nicotine concentration, or duration by frequency of use in past 30-day e-cigarette users. One-third of past 30-day and almost half of past-year users did not know the nicotine concentration of their cartridge or e-liquid. Correlations between all e-cigarette use measures were low, with the highest correlations seen between e-liquid quantity and cartridge quantity in all past 30-day users (r = 0.28) and those reporting any e-liquid use (r = 0.40). Cronbach's alpha and mean interitem correlations were low across all user groups. Conclusions: Low to moderate correlation across e-cigarette measures in e-cigarette users implies low internal consistency of these measures in a population survey. Findings suggest measures such as quantity and nicotine concentration might more appropriate in samples of recent experienced e-cigarette users than in general population samples
Carbon Isotope Ratios in M10 Giants
No full textWe measured carbon abundances and the ratio in 31 giant branch stars with previous CN and CH band measurements that span -2.33 < M < 0.18 in the globular cluster M10 (NGC 6254). Abundances were determined by comparing CO features at and specifically the O bandhead at , to synthetic spectra generated with MOOG. The observed spectra were obtained with GNIRS on Gemini North with a resolution of R ≈3500. The carbon abundances derived from the IR spectra agree with previous [C/Fe] measurements found using CN and CH features at the near-UV/blue wavelength range. We found an average carbon isotope ratio of = 5.10 for first generation stars (CN-normal; 13 stars total) and = 4.84 for second generation stars (CN-enhanced; 15 stars). We therefore find no statistically significant difference in ratio between stars in either population for the observed magnitude range. Finally, we created models of the expected carbon, nitrogen, and surface abundance evolution on the red giant branch due to thermohaline mixing using the MESA stellar evolution code. The efficiency of the thermohaline mixing must be increased to a factor of ≈60 to match [C/Fe] abundances, and by a factor of ≈666 to match ratios. We could not simultaneously fit the evolution of both carbon and the ratio with models using the same thermohaline efficiency parameter
Assessing Higher Order Language Processing in Long-Term Cochlear Implant Users
No full textPurpose The purpose of this study was to describe and explain individual differences in complex/higher order language processing in long-term cochlear implant (CI) users relative to normal-hearing (NH) peers. Method Measures of complex/higher order language processing indexed by the Clinical Evaluation of Language Fundamentals–Fourth Edition (CELF-4) Core Language subtests were obtained from 53 long-term (≥ 7 years) CI users aged 9–29 years and 60 NH controls who did not differ in age, gender, or nonverbal IQ. Vocabulary knowledge and fast, automatic language processing (rapid phonological coding, verbal rehearsal speed, and speech intelligibility) were also assessed. Results CI users showed weaker performance than NH controls on all CELF-4 Core Language subtests. These differences remained for Formulated Sentences and Recalling Sentences even when vocabulary knowledge was statistically controlled. About 50% of the CI sample scored within the range of the NH sample on Formulated Sentences and Recalling Sentences, while the remaining 50% scored well below the NH sample on these subtests. Vocabulary knowledge, rapid phonological coding, verbal rehearsal speed, and speech intelligibility were more strongly correlated with CELF-4 subtest scores in the CI sample than in the NH sample. Conclusions Weaknesses in complex, higher order language processing shown by a subgroup of CI users compared to NH peers may result from delays in fast, automatic processing of language. These at-risk domains of language functioning could serve as targets for novel interventions for deaf children who experience suboptimal spoken language outcomes following cochlear implantation
K-Core Structure of Real Multiplex Networks
No full textMultiplex networks are convenient mathematical representations for many real-world—biological, social, and technological—systems of interacting elements, where pairwise interactions among elements have different flavors. Previous studies pointed out that real-world multiplex networks display significant interlayer correlations—degree-degree correlation, edge overlap, node similarities—able to make them robust against random and targeted failures of their individual components. Here, we show that interlayer correlations are important also in the characterization of their k -core structure, namely, the organization in shells of nodes with an increasingly high degree. Understanding of k -core structures is important in the study of spreading processes taking place on networks, as for example in the identification of influential spreaders and the emergence of localization phenomena. We find that, if the degree distribution of the network is heterogeneous, then a strong k -core structure is well predicted by significantly positive degree-degree correlations. However, if the network degree distribution is homogeneous, then strong k -core structure is due to positive correlations at the level of node similarities. We reach our conclusions by analyzing different real-world multiplex networks, introducing novel techniques for controlling interlayer correlations of networks without changing their structure, and taking advantage of synthetic network models with tunable levels of interlayer correlations