bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanisms underlying spruce budworm outbreak processes as elucidated by a 14‐year study in New Brunswick, Canada
Authors: Royama T. , Eveleigh E. S. , Morin J. R. B. , Pollock S. J. , McCarthy P. C. , McDougall G. A. , Lucarotti C. J. 
Published: July 2017

AbstractWe conducted a 14‐yr intensive study of spruce budworm (Choristoneura fumiferana (Clem.)) survivorship at three study plots in largely balsam fir (Abies balsamea (L.) Mill.) stands in New Brunswick, Canada, to elucidate certain key mechanisms underlying spruce budworm outbreak cycles. The study covered a peak‐to‐declining phase (from 1981 and 1994) of the budworm outbreak cycle that had started in the early 1960s. Frequent sampling was carried out in each plot‐year to construct a practically continuous survivorship curve, and the annual variation in population density was estimated. We found a high level of correlation between the studied phase of the outbreak cycle and annual variations in the survivorship over the postdiapause period, suggesting that postdiapause survivorship was the chief determinant of the cycle. We found the annual changes in population density in the present study to be closely similar in pattern to those from the provincial budworm surveys conducted in much larger areas. This implies that the mechanism underlying the population process found in the few study plots in largely balsam fir stands also applies to the process in much larger areas of diverse stand types. The main source of postdiapause mortality is found to be natural enemies. The impacts of parasitoids and disease are evaluated by rearing budworm samples in the laboratory. Hymenopteran and dipteran parasitoids are by far the major sources of mortality, and microsporidians are the most prevalent pathogen. Occurrences of other entomopathogenic fungi and viruses were insignificant throughout the study. Seasonal changes in laboratory survivorship are compared with the corresponding field survivorship to estimate the effect of predation. No major mortality factor is found to singly play a predominant role in determining the outbreak cycle. Conversely, some minor factors are shown to have played significant roles. Thus, the importance of recognizing the action of natural enemies as a complex is emphasized for understanding the budworm outbreak cycle. Finally, centered on the roles played by the chronological succession of natural enemies in the present study, the results of budworm research in New Brunswick since the mid‐1940s are synthesized to outline basic mechanisms underlying the outbreak processes as a guide for further studies.
Hydroaminomethylation of oleochemicals: A comprehensive overview
Authors: Vanbésien Théodore , Le Nôtre Jérôme , Monflier Eric , Hapiot Frédéric 
Published: July 2017

The present review explores the historical background of the rhodium‐catalyzed hydroaminomethylation (HAM) of vegetable oils and the recent developments in this field. The reaction conditions are especially discussed and commented upon. Various amines have been grafted onto alkyl chains of vegetable oils, thus giving rise to a wide range of bio‐based HAM‐products. A focus is on bifunctional HAM‐products as they have potential as monomers in polymer chemistry. The nature of the ligands stabilizing the rhodium catalytic species is also discussed. The catalytic results obtained with phosphanes and amines are analyzed and compared. The goal of this review is to convince the reader that HAM of vegetable oils is a simple and effective synthetic pathway to access valuable functionalized bio‐based compounds with industrial potential.Practical applications: Products resulting from hydroaminomethylation of vegetable oils have potential as monomers in polymer chemistry and as bio‐based surface‐active agents.The functionalization of the carbon–carbon double bonds of vegetable oils by amino groups is easily carried out via rhodium‐catalyzed hydroaminomethylation (HAM).
Detection of growth rate‐dependent product formation in miniaturized parallel fed‐batch cultivations
Authors: Glauche Florian , Glazyrina Julia , Cruz Bournazou Mariano Nicolas , Kiesewetter Gregor , Cuda Fabian , Goelling Detlef , Raab Andreas , Lang Christine , Neubauer Peter 
Published: July 2017

AbstractSaccharomyces cerevisiae is a popular expression system for recombinant proteins. In most cases, production processes are performed as carbon‐limited fed‐batch cultures to avoid aerobic ethanol formation. Especially for constitutive expression systems, the specific product formation rate depends on the specific growth rate. The development of optimal feeding strategies strongly depends on laboratory‐scale cultivations, which are time and resource consuming, especially when continuous experiments are carried out. It is therefore beneficial for accelerated process development to look at alternatives. In this study, S. cerevisiae AH22 secreting a heterologous endo‐polygalacturonase (EPG) was characterized in microwell plates with an enzyme‐based fed‐batch medium. Through variation of the glucose release rate, different growth profiles were established and the impact on EPG secretion was analyzed. Product formation rates of 200–400 U (gx h)−1 were determined. As a reference, bioreactor experiments using the change‐stat cultivation technique were performed. The growth‐dependent product formation was analyzed over dilution rates of D = 0.01–0.35 with smooth change of D at a rate of 0.003 h−2. EPG production was found to be comparable with a qp of 400 U (gx h)−1 at D = 0.27 h−1. The presented results indicate that parallel miniaturized fed‐batch cultures can be applied to determine product formation profiles of putative production strains. With further automation and parallelization of the concept, strain characterization can be performed in shorter time.
Enzymes Suitable for Biorefinery to Coproduce Hexaric Acids and Electricity from Hexuronic Acids Derived from Biomass
Authors: Sakuta Riku , Takeda Kouta , Igarashi Kiyohiko , Ohno Hiroyuki , Nakamura Nobuhumi 
Published: July 2017

AbstractHexarates are platform chemicals. Methods to produce d‐glucarate and d‐mannarate are desirable because these hexarates can be gained by oxidation of the corresponding hexuronates, which are abundantly found in algae and plants as the units of polyuronates. Oxidative production of the hexarates can be combined with a reductive reaction to coproduce electricity. An enzymatic biofuel cell is a device that enables this coproduction. To construct the cell, it is necessary to find enzymes that catalyze platform chemical production and are also suitable as anode catalysts. Here, we show the production of d‐glucarate and d‐mannarate from d‐glucuronate and d‐mannuronate, with both reactions catalyzed by pyrroloquinoline quinone (PQQ)‐dependent glucose dehydrogenase, in addition to the production of d‐glucarate from l‐guluronate by the PQQ domain of pyranose dehydrogenase from Coprinopsis cinerea. The enzymes are suitable as anode catalysts in biofuel cells that coproduce these hexarates and electricity.
Efficient and Stable Inverted Planar Perovskite Solar Cells Employing CuI as Hole‐Transporting Layer Prepared by Solid–Gas Transformation
Authors: Wang Haoxin , Yu Ze , Jiang Xiao , Li Jiajia , Cai Bin , Yang Xichuan , Sun Licheng 
Published: July 2017

AbstractThe inorganic p‐type semiconductor CuI possesses several unique characteristics such as high transparency, low‐production cost, high hole mobility, and good chemical stability and is a promising hole‐transporting material candidate that can be explored in solar‐cell devices. Herein, we adopt a simple solid–gas reaction method to fabricate a uniform CuI film by exposing a thermally evaporated copper film to iodine vapor and apply it as a hole‐transporting layer (HTL) in inverted planar perovskite solar cells (PSCs). The optimized devices display a promising power conversion (PCE) efficiency of 14.7 %, with an open‐circuit voltage of 1.04 V, a short‐circuit current density of 20.9 mW cm−2, and a fill factor of 0.68. This is one of the highest PCE values reported so far for CuI‐based HTL in PSCs. Moreover, the devices studied also exhibit good long‐term stability at ambient atmosphere, arising from the hydrophobicity of CuI HTL. The results highlight that CuI fabricated using the simple and low‐temperature processing method presented here holds great promise as low‐cost alternative HTL material for the development of efficient and stable inverted planar PSCs in the future.
Spectral variations of underwater river sounds
Authors: Geay T. , Belleudy P. , Laronne J.B. , Camenen B. , Gervaise C. 
Published: July 2017

AbstractPassive acoustic monitoring of the self‐generated noise of particle impacts has been shown to be correlated to bedload flux and bedload size. However, few studies have concentrated on the role of acoustic wave propagation in a river. For the first time, the river environment is modeled as a Pekeris waveguide, where a wave number integration technique is used to predict the transformation of sounds through their propagation paths. Focusing on the distance of a hydrophone from the channel bed and cutting off the low frequencies produced by impacts between gravel particles, we demonstrate that acoustic propagation modifies the spectral content of bedload‐generated sound. Acoustic signals analyzed with the proposed model are interpreted by comparison to Helley–Smith bedload data obtained during flood conditions on the large gravel‐bedded Arc‐en‐Maurienne River, France.This study shows that careful attention to acoustic propagation effects is required when estimating bedload grain size distribution with hydrophones in rivers, especially for rivers with slopes higher than 1%. Bedload monitoring with a hydrophone is particularly appropriate for large gravel‐bed rivers – especially so during large floods, when in situ sampling is difficult or impractical and the impact of acoustic propagation is weaker relative to the self‐generated noise of bedload impacts. Copyright © 2017 John Wiley & Sons, Ltd.
Gender and Minority Achievement Gaps in Science in Eighth Grade: Item Analyses of Nationally Representative Data
Authors: Qian Xiaoyu , Nandakumar Ratna , Glutting Joseph , Ford Danielle , Fifield Steve 
Published: July 2017

AbstractIn this study, we investigated gender and minority achievement gaps on 8th‐grade science items employing a multilevel item response methodology. Both gaps were wider on physics and earth science items than on biology and chemistry items. Larger gender gaps were found on items with specific topics favoring male students than other items, for example, an earth science item requiring visual–spatial ability. Minority students were more likely than White students to score lower on harder constructed‐response (CR) items. Some teachers were more likely to reduce minority achievement gaps on easier CR items than other teachers. Implications for instruction in terms of improving visual–spatial awareness, efficacy of female students, and modeling scientific literacy for minority students were discussed.
Projection of population structure in China using least squares support vector machine in conjunction with a Leslie matrix model
Authors: Li Shuang , Yang Zewei , Li Hongsheng , Shu Guangwen 
Published: July 2017

AbstractChina is a populous country that is facing serious aging problems due to the single‐child birth policy. Debate is ongoing whether the liberalization of the single‐child policy to a two‐child policy can mitigate China's aging problems without unacceptably increasing the population. The purpose of this paper is to apply machine learning theory to the demographic field and project China's population structure under different fertility policies. The population data employed derive from the fifth and sixth national census records obtained in 2000 and 2010 in addition to the annals published by the China National Bureau of Statistics. Firstly, the sex ratio at birth is estimated according to the total fertility rate based on least squares regression of time series data. Secondly, the age‐specific fertility rates and age‐specific male/female mortality rates are projected by a least squares support vector machine (LS‐SVM) model, which then serve as the input to a Leslie matrix model. Finally, the male/female age‐specific population data projected by the Leslie matrix in a given year serve as the input parameters of the Leslie matrix for the following year, and the process is iterated in this manner until reaching the target year. The experimental results reveal that the proposed LS‐SVM‐Leslie model improves the projection accuracy relative to the conventional Leslie matrix model in terms of the percentage error and mean algebraic percentage error. The results indicate that the total fertility ratio should be controlled to around 2.0 to balance concerns associated with a large population with concerns associated with an aging population. Therefore, the two‐child birth policy should be fully instituted in China. However, the fertility desire of women tends to be low due to the high cost of living and the pressure associated with employment, particularly in the metropolitan areas. Thus additional policies should be implemented to encourage fertility.
De‐extinction and Conservation Genetics in the Anthropocene
Authors: Sandler Ronald 
Published: July 2017

AbstractOne interesting feature of de‐extinction—particularly with respect to long‐extinct species such as the passenger pigeon, thylacine, and mammoth—is that it does not fit neatly into the primary rationales for adopting novel ecosystem‐management and species‐conservation technologies and strategies: efficiency and necessity. The efficiency rationale is that the new technology or strategy enables conservation biologists to do what they already do more effectively. Why should researchers embrace novel information technologies? Because they allow scientists to better track, monitor, map, aggregate, and analyze species behaviors, biological systems, and human‐environment interactions. This enables better decision‐making about how to protect species, which areas to conserve, and how to reduce anthropogenic impacts on ecological systems. Many projects in conservation genomics are justified in this way. But de‐extinction is not a more efficient or necessary means to some conservation aim that is already recognized as acceptable or important. In fact, because it is focused on reconstituting approximations of nonexistent species, rather than maintaining extant ones, the social and ethical assessment of de‐extinction is not limited to asking whether it is a good means. We can ask as well whether de‐extinction is a worthwhile “conservation” goal in the first place.
The Spectacular Garden: Where Might De‐extinction Lead?
Authors: Kaebnick Gregory E. 
Published: July 2017

AbstractThe emergence of de‐extinction is a study in technological optimism. What has already been accomplished in recovering ancient genomes, recreating them, and reproducing animals with engineered genomes is amazing but also has a long ways to go to achieve “de‐extinction” as most people would understand that term. Still, with some caveats in place, creating a functional replacement for an extinct species may sometimes be doable, and given the right goals, might sometimes make sense. The International Union for Conservation of Nature guidelines for de‐extinction do a reasonable job of keeping the caveats in place and clarifying the goals. In fact, given the right caveats about what de‐extinction can accomplish, we should pay a lot of attention to the technology and should think carefully about the goals. Not only has the technology been advancing, but our environmental standards have been getting looser and more flexible, providing less guidance for implementing the technology.The guiding ideals for conservation are often explained as a choice between John Muir, founder of The Sierra Club, and Gifford Pinchot, who helped create the U.S. Forest Service. Muir argued for preserving some places in the world in their natural state because of their great value and beauty. Pinchot, by contrast, was bluntly utilitarian. He argued for trying to keep some natural places more or less undamaged so that we could use them later. There has long been dissatisfaction with this choice, and in the last couple of decades, a number of prominent voices have proposed a “gardening ethic” as a new standard that combines elements of Muir and Pinchot. A gardening ethic is supposed to both celebrate the land and declare that it must now be managed. But what would good gardening mean when it comes to de‐extinction?
Neural signature of inattentional deafness
Authors: Durantin Gautier , Dehais Frederic , Gonthier Nicolas , Terzibas Cengiz , Callan Daniel E. 
Published: July 2017

AbstractInattentional deafness is the failure to hear otherwise audible sounds (usually alarms) that may occur under high workload conditions. One potential cause for its occurrence could be an attentional bottleneck that occurs when task demands are high, resulting in lack of resources for processing of additional tasks. In this fMRI experiment, we explore the brain regions active during the occurrence of inattentional deafness using a difficult perceptual‐motor task in which the participants fly through a simulated Red Bull air race course and at the same time push a button on the joystick to the presence of audio alarms. Participants were instructed to focus on the difficult piloting task and to press the button on the joystick quickly when they noticed an audio alarm. The fMRI results revealed that audio misses relative to hits had significantly greater activity in the right inferior frontal gyrus IFG and the superior medial frontal cortex. Consistent with an attentional bottleneck, activity in these regions was also present for poor flying performance (contrast of gates missed versus gates passed for the flying task). A psychophysiological interaction analysis from the IFG identified reduced effective connectivity to auditory processing regions in the right superior temporal gyrus for missed audio alarms relative to audio alarms that were heard. This study identifies a neural signature of inattentional deafness in an ecologically valid situation by directly measuring differences in brain activity and effective connectivity between audio alarms that were not heard compared to those that were heard. Hum Brain Mapp 38:5440–5455, 2017. © 2017 Wiley Periodicals, Inc.
Cortical connectivity modulation during sleep onset: A study via graph theory on EEG data
Authors: Vecchio Fabrizio , Miraglia Francesca , Gorgoni Maurizio , Ferrara Michele , Iberite Francesco , Bramanti Placido , De Gennaro Luigi , Rossini Paolo Maria 
Published: July 2017

AbstractSleep onset is characterized by a specific and orchestrated pattern of frequency and topographical EEG changes. Conventional power analyses of electroencephalographic (EEG) and computational assessments of network dynamics have described an earlier synchronization of the centrofrontal areas rhythms and a spread of synchronizing signals from associative prefrontal to posterior areas. Here, we assess how “small world” characteristics of the brain networks, as reflected in the EEG rhythms, are modified in the wakefulness–sleep transition comparing the pre‐ and post‐sleep onset epochs. The results show that sleep onset is characterized by a less ordered brain network (as reflected by the higher value of small world) in the sigma band for the frontal lobes indicating stronger connectivity, and a more ordered brain network in the low frequency delta and theta bands indicating disconnection on the remaining brain areas. Our results depict the timing and topography of the specific mechanisms for the maintenance of functional connectivity of frontal brain regions at the sleep onset, also providing a possible explanation for the prevalence of the frontal‐to‐posterior information flow directionality previously observed after sleep onset. Hum Brain Mapp 38:5456–5464, 2017. © 2017 Wiley Periodicals, Inc.
The impact of T1 versus EPI spatial normalization templates for fMRI data analyses
Authors: Calhoun Vince D. , Wager Tor D. , Krishnan Anjali , Rosch Keri S. , Seymour Karen E. , Nebel Mary Beth , Mostofsky Stewart H. , Nyalakanai Prashanth , Kiehl Kent 
Published: July 2017

AbstractSpatial normalization of brains to a standardized space is a widely used approach for group studies in functional magnetic resonance imaging (fMRI) data. Commonly used template‐based approaches are complicated by signal dropout and distortions in echo planar imaging (EPI) data. The most widely used software packages implement two common template‐based strategies: (1) affine transformation of the EPI data to an EPI template followed by nonlinear registration to an EPI template (EPInorm) and (2) affine transformation of the EPI data to the anatomic image for a given subject, followed by nonlinear registration of the anatomic data to an anatomic template, which produces a transformation that is applied to the EPI data (T1norm). EPI distortion correction can be used to adjust for geometric distortion of EPI relative to the T1 images. However, in practice, this EPI distortion correction step is often skipped. We compare these template‐based strategies empirically in four large datasets. We find that the EPInorm approach consistently shows reduced variability across subjects, especially in the case when distortion correction is not applied. EPInorm also shows lower estimates for coregistration distances among subjects (i.e., within‐dataset similarity is higher). Finally, the EPInorm approach shows higher T values in a task‐based dataset. Thus, the EPInorm approach appears to amplify the power of the sample compared to the T1norm approach when not using distortion correction (i.e., the EPInorm boosts the effective sample size by 12–25%). In sum, these results argue for the use of EPInorm over the T1norm when no distortion correction is used. Hum Brain Mapp 38:5331–5342, 2017. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
A portable experimental hillslope for frozen ground studies
Authors: Pratt Dyan L. , McDonnell Jeffrey J. 
Published: July 2017

AbstractFrozen ground hydrological effects on runoff, storage, and release have been observed in the field and tested in numerical models, but few physical models of frozen slopes (at scales from 1 to 15 m) exist partly because the design of such an experiment requires new engineering design for realistic whole‐slope freezing and physical model innovation. Here, we present a new freezable tilting hillslope physical model for hydrological system testing under a variety of climate conditions with the ability to perform multiple (up to 20 per year) freeze–thaw cycles. The 4 × 2 m hillslope is mobile and tiltable on the basis of a modified tri‐axle 4.88‐m (16′) dump trailer to facilitate testing multiple configurations. The system includes controllable boundary conditions on all surfaces; examples of side and baseflow boundary conditions include permeable membranes, impermeable barriers, semipermeable configurations, and constant head conditions. To simulate cold regions and to freeze the hillslope in a realistic and controlled manner, insulation and a removable freezer system are incorporated onto the top boundary of the hillslope. The freezing system is designed to expedite the freezing process by the addition of a 10,130‐KJ (9,600‐BTU) refrigeration coil to the top‐centre of the insulated ceiling. Centre placement provides radial freezing of the hillslope in a top‐down fashion, similar to what natural systems encounter in the environment. The perimeter walls are insulated with 100 mm of spray foam insulation, whereas the base of the hillslope is not insulated to simulate natural heat fluxes beneath the frozen layer of soil. Our preliminary testing shows that covers can be frozen down to −10 °C in approximately 7 days, with subsequent thaw on a similar time frame.