bluuebunny/crossref_metadata_2025_split huggingface dataset:
New insights into the column CH2O/NO2 ratio as an indicator of near‐surface ozone sensitivity
Authors: Schroeder Jason R. , Crawford James H. , Fried Alan , Walega James , Weinheimer Andrew , Wisthaler Armin , Müller Markus , Mikoviny Tomas , Chen Gao , Shook Michael , Blake Donald R. , Tonnesen Gail S. 
Published: July 2017

AbstractSatellite‐based measurements of the column CH2O/NO2 ratio have previously been used to estimate near‐surface ozone (O3) sensitivity (i.e., NOx or VOC limited), and the forthcoming launch of air quality‐focused geostationary satellites provides a catalyst for reevaluating the ability of satellite‐measured CH2O/NO2 to be used in this manner. In this study, we use a 0‐D photochemical box model to evaluate O3 sensitivity and find that the relative rate of radical termination from radical‐radical interactions to radical‐NOx interactions (referred to as LROx/LNOx) provides a good indicator of maximum O3 production along NOx ridgelines. Using airborne measurements from NASA's Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relative to Air Quality (DISCOVER‐AQ) deployments in Colorado, Maryland, and Houston, we show that in situ measurements of CH2O/NO2 can be used to indicate O3 sensitivity, but there is an important “transition/ambiguous” range whereby CH2O/NO2 fails to categorize O3 sensitivity, and the range and span of this transition/ambiguous range varies regionally. Then, we apply these findings to aircraft‐derived column density measurements from DISCOVER‐AQ and find that inhomogeneities in vertical mixing in the lower troposphere further degrades the ability of column CH2O/NO2 to indicate near‐surface O3 sensitivity (i.e., the transition/ambiguous range is much larger than indicated by in situ data alone), and we hypothesize that the global transition/ambiguous range is sufficiently large to make the column CH2O/NO2 ratio unuseful for classifying near‐surface O3 sensitivity. Lastly, we present a case study from DISCOVER‐AQ‐Houston that suggests that O3 sensitivity on exceedance days may be substantially different than on nonexceedance days (which may be observable from space) and explore the diurnal evolution of O3 sensitivity, O3 production, and the column CH2O/NO2 ratio. The results of these studies suggest that although satellite measurements of CH2O/NO2 alone may not be sufficient for accurately classifying near‐surface O3 sensitivity, new techniques offered by geostationary platforms may nonetheless provide methods for using space‐based measurements to develop O3 mitigation strategies.
Spatial patterns of DOC concentration and DOM optical properties in a Brazilian tropical river‐wetland system
Authors: Dalmagro Higo J. , Johnson Mark S. , de Musis Carlo R. , Lathuillière Michael J. , Graesser Jordan , Pinto‐Júnior Osvaldo B. , Couto Eduardo G. 
Published: July 2017

AbstractThe Cerrado (savanna) and Pantanal (wetland) biomes of Central Western Brazil have experienced significant development activity in recent decades, including extensive land cover conversion from natural ecosystems to agriculture and urban expansion. The Cuiabá River transects the Cerrado biome prior to inundating large areas of the Pantanal, creating one of the largest biodiversity hot spots in the world. We measured dissolved organic carbon (DOC) and the optical absorbance and fluorescence properties of dissolved organic matter (DOM) from 40 sampling locations spanning Cerrado and Pantanal biomes during wet and dry seasons. In the upper, more agricultural region of the basin, DOC concentrations were highest in the rainy season with more aromatic and humified DOM. In contrast, DOC concentrations and DOM optical properties were more uniform for the more urbanized middle region of the basin between wet and dry seasons, as well as across sample locations. In the lower region of the basin, wet season connectivity between the river and the Pantanal floodplain led to high DOC concentrations, a fourfold increase in humification index (HIX) (an indicator of DOM humification), and a 50% reduction in the spectral slope (SR). Basin‐wide, wet season values forSR, HIX, and FI (fluorescence index) indicated an increasing representation of terrestrially derived DOM that was more humified. Parallel factor analysis identified two terrestrially derived components (C1 and C2) representing 77% of total fluorescing DOM (fDOM). A third, protein‐like fDOM component increased markedly during the wet season within the more urban‐impacted region.
2‐Iodoxybenzoic Acid Tosylates: the Alternative to Dess–Martin Periodinane Oxidizing Reagents
Authors: Yusubov Mekhman S. , Postnikov Pavel S. , Yusubova Roza Ya. , Yoshimura Akira , Jürjens Gerrit , Kirschning Andreas , Zhdankin Viktor V. 
Published: July 2017

AbstractTwo powerful hypervalent iodine(V) oxidants, DMP‐OTs (1‐tosyloxy‐1,1‐diacetoxy‐1H‐1λ5‐benzo[d][1,2]iodoxol‐3‐one) and IBX‐OTs (1‐tosyloxy‐1‐oxo‐1H‐1λ5‐benzo[d][1,2]iodoxol‐3‐one) show high reactivity in the oxidation of structurally complex primary and secondary alcohols, which are highly functionalized polyketide or terpene fragments or steroids. The yields of the corresponding carbonyl compounds are even higher for the protocol that uses pyridine as additive. The oxidations proceed very rapidly at room temperature leaving the protective groups and π‐systems intact and affording the corresponding carbonyl compounds in good to excellent yields. Moreover, IBX‐OTs is an efficient reagent for the oxidative dehydrogenation of steroidal alcohols to the corresponding enones.magnified image
Carbon Nitride Aerogels for the Photoredox Conversion of Water
Authors: Ou Honghui , Yang Pengju , Lin Lihua , Anpo Masakazu , Wang Xinchen 
Published: July 2017

AbstractAerogel structures have attracted increasing research interest in energy storage and conversion owing to their unique structural features, and a variety of materials have been engineered into aerogels, including carbon‐based materials, metal oxides, linear polymers and even metal chalcogenides. However, manufacture of aerogels from nitride‐based materials, particularly the emerging light‐weight carbon nitride (CN) semiconductors is rarely reported. Here, we develop a facile method based on self‐assembly to produce self‐supported CN aerogels, without using any cross‐linking agents. The combination of large surface area, incorporated functional groups and three‐dimensional (3D) network structure, endows the resulting freestanding aerogels with high photocatalytic activity for hydrogen evolution and H2O2 production under visible light irradiation. This work presents a simple colloid chemistry strategy to construct 3D CN aerogel networks that shows great potential for solar‐to‐chemical energy conversion by artificial photosynthesis.
Generation of apoptosis‐resistant HEK293 cells with CRISPR/Cas mediated quadruple gene knockout for improved protein and virus production
Authors: Zhang Weifeng , Xiao Dan , Shan Linlin , Zhao Junli , Mao Qinwen , Xia Haibin 
Published: July 2017

AbstractApoptosis has important functions during pathophysiologic processes. However, from a biopharmaceutical point of view, active apoptosis of host cells is undesirable during viral packaging or protein expression, because it decreases the efficiency of viral or protein production. Here we used the CRISPR/Cas technique to knock out four pro‐apoptotic genes, Caspase3, Caspase6, Caspase7 and AIF1, in HEK293 cells, and successfully produced an apoptosis‐resistant cell line. Furthermore, this cell line showed higher expression levels of pro‐apoptotic proteins and higher packaging efficiency for the virus carrying these proteins than control HEK293 cells. This study not only produced an apoptosis‐resistant cell line that is useful in producing apoptosis‐inducing proteins or viruses expressing these proteins, but also provides a methodology to build other apoptosis‐resistant cell lines.
Confining Gold Nanoclusters in Highly Defective Graphitic Layers To Enhance the Methanol Electrooxidation Reaction
Authors: Mao Zhe , Hu Haihua , Su Rui , Liu Peizhi , Li Yixing , Zhang Wenting , Zhao Xiaoning , Guo Junjie , Guan Pengfei , Qin Gaowu , Zhang Xuefeng 
Published: July 2017

AbstractThe development of a highly efficient catalyst possessing both high activity and remarkable stability is a major focus in fuel‐cell applications. Herein, we utilized an arc‐discharge approach with an ultrafast cooling system to synthesize a core@shell structural Au@C nanocomposite comprising 3–5 nm gold clusters confined within highly defective graphitic layers. Such a construction not only improves the conductivity to accelerate the penetration of ions and electrons during the electrocatalytic process of methanol molecules, but it also suppresses chemical/thermal coarsening of the gold clusters. More importantly, the atomic‐scale Au/C interfaces contribute to a synergistic effect and enhance the activity relative to that of other gold‐based catalysts in the electrooxidation of methanol. This work highlights the role of heterogeneous interfaces in the catalytic efficiency of precious‐metal catalysts and rationalizes optimization in catalyst engineering.
Origin of enhanced VCD in amyloid fibril spectra: Effect of deuteriation and pH
Authors: Pazderková Markéta , Pazderka Tomáš , Shanmugasundaram Maruda , Dukor Rina K. , Lednev Igor K. , Nafie Laurence A. 
Published: July 2017

AbstractSupramolecular chirality of amyloid fibrils, protein aggregates related to many neurodegenerative diseases, is a remarkable property associated with fibril structure and polymorphism. Since its discovery almost 10 years ago there is still little understanding of this phenomenon, including the cause of the highly enhanced vibrational circular dichroism (VCD) intensity arising from fibril supramolecular chirality. In this study, VCD spectra, enhanced by filament supramolecular chirality, are presented for lysozyme and insulin fibrils above and below pH 2 and after deuterium exchange, above and below pD 2. Supramolecular chirality (observed by VCD) and fibril morphology (documented by atomic force microscopy) are not affected by protein deuteriation. In D2O the fibril VCD sign pattern changes to fewer bands, with implications for the amide I/II origin of enhanced VCD intensity. Separation of amide I and II signals will facilitate calculations of enhanced VCD spectra of amyloid fibrils and enable a better understanding of the origin of the VCD sign pattern.
Reliable HPLC separation, vibrational circular dichroism spectra, and absolute configurations of isoborneol enantiomers
Authors: Gao Rui‐Qi , Fan Jun , Tan Qi , Guo Dong , Chen Tao , He Ru‐Jian , Li Dan , Zhang Hui , Zhang Wei‐Guang 
Published: July 2017

AbstractResolution of chiral compounds has played an important role in the pharmaceutical field, involving detailed studies of pharmacokinetics, physiological, toxicological, and metabolic activities of enantiomers. Herein, a reliable method by high‐performance liquid chromatography (HPLC) coupled with an optical rotation detector was developed to separate isoborneol enantiomers. A cellulose tris(3, 5‐dimethylphenylcarbamate)‐coated chiral stationary phase showed the best separation performance for isoborneol enantiomers in the normal phase among four polysaccharide chiral packings. The effects of alcoholic modifiers and column temperature were studied in detail. Resolution of the isoborneol racemate displayed a downward trend along with an increase in the content of ethanol and column temperature, indicating that less ethanol in the mobile phase and lower temperature were favorable to this process. Moreover, two isoborneol enantiomers were obtained via a semipreparative chiral HPLC technique under optimum conditions, and further characterized by analytical HPLC, and experimental and calculated vibrational circular dichroism (VCD) spectroscopy, respectively. The solution VCD spectrum of the first‐eluted component was consistent with the Density Functional Theory (DFT) calculated pattern based on the SSS configuration, indicating that this enantiomer should be (1S, 2S, 4S)‐(+)‐isoborneol. Briefly, these results have provided reliable information to establish a method for analysis, preparative separation, and absolute configuration of chiral compounds without typical chromophoric groups.
Coevolution of competing Callosobruchus species does not stabilize coexistence
Authors: Hausch Stephen J. , Fox Jeremy W. , Vamosi Steven M. 
Published: July 2017

AbstractInterspecific resource competition is expected to select for divergence in resource use, weakening interspecific relative to intraspecific competition, thus promoting stable coexistence. More broadly, because interspecific competition reduces fitness, any mechanism of interspecific competition should generate selection favoring traits that weaken interspecific competition. However, species also can adapt to competition by increasing their competitive ability, potentially destabilizing coexistence. We reared two species of bean beetles, the specialist Callosobruchus maculatus and the generalist C. chinensis, in allopatry and sympatry on a mixture of adzuki beans and lentils, and assayed mutual invasibility after four, eight, and twelve generations of evolution. Contrary to the expectation that coevolution of competitors will weaken interspecific competition, the rate of mutual invasibility did not differ between sympatry and allopatry. Rather, the invasion rate of C. chinensis, but not C. maculatus, increased with duration of evolution, as C. chinensis adapted to lentils without experiencing reduced adaptation to adzuki beans, and regardless of the presence or absence of C. maculatus. Our results highlight that evolutionary responses to interspecific competition promote stable coexistence only under specific conditions that can be difficult to produce in practice.
Mixture toxicity in the marine environment: Model development and evidence for synergism at environmental concentrations
Authors: Deruytter David , Baert Jan M. , Nevejan Nancy , De Schamphelaere Karel A.C. , Janssen Colin R. 
Published: July 2017

Abstract

Little is known about the effect of metal mixtures on marine organisms, especially after exposure to environmentally realistic concentrations. This information is, however, required to evaluate the need to include mixtures in future environmental risk assessment procedures. We assessed the effect of copper (Cu)–Nickel (Ni) binary mixtures on Mytilus edulis larval development using a full factorial design that included environmentally relevant metal concentrations and ratios. The reproducibility of the results was assessed by repeating this experiment 5 times. The observed mixture effects were compared with the effects predicted with the concentration addition model. Deviations from the concentration addition model were estimated using a Markov chain Monte-Carlo algorithm. This enabled the accurate estimation of the deviations and their uncertainty. The results demonstrated reproducibly that the type of interaction—synergism or antagonism—mainly depended on the Ni concentration. Antagonism was observed at high Ni concentrations, whereas synergism occurred at Ni concentrations as low as 4.9 μg Ni/L. This low (and realistic) Ni concentration was 1% of the median effective concentration (EC50) of Ni or 57% of the Ni predicted-no-effect concentration (PNEC) in the European Union environmental risk assessment. It is concluded that results from mixture studies should not be extrapolated to concentrations or ratios other than those investigated and that significant mixture interactions can occur at environmentally realistic concentrations. This should be accounted for in (marine) environmental risk assessment of metals. Environ Toxicol Chem 2017;36:3471–3479. © 2017 SETAC.
Clinical features and prognostic impact of PRDM16 expression in adult acute myeloid leukemia
Authors: Yamato Genki , Yamaguchi Hiroki , Handa Hiroshi , Shiba Norio , Kawamura Machiko , Wakita Satoshi , Inokuchi Koiti , Hara Yusuke , Ohki Kentaro , Okubo Jun , Park Myoung‐Ja , Sotomatsu Manabu , Arakawa Hirokazu , Hayashi Yasuhide 
Published: July 2017

AbstractHigh PRDM16 (also known as MEL1) expression is a representative marker of acute myeloid leukemia (AML) with NUP98‐NSD1 and is a significant predictive marker for poor prognosis in pediatric AML. However, the clinical features of adult AML with PRDM16 expression remain unclear. PRDM16 is highly homologous to MDS1/EVI1, which is an alternatively spliced transcript of MECOM (also known as EVI1). We investigated PRDM16 expression in 151 AML patients, with 47 (31%) exhibiting high PRDM16 expression (PRDM16/ABL1 ratio ≥ 0.010). High PRDM16 expression significantly correlated with DNMT3A (43% vs. 15%, P < 0.001) and NPM1 (43% vs. 21%, P = 0.010) mutations and partial tandem duplication of KMT2A (22% vs. 1%, P < 0.001). Remarkably, high‐PRDM16‐expression patients were frequent in the noncomplete remission group (48% vs. 21%, P = 0.002). Overall survival (OS) was significantly worse in high‐PRDM16‐expression patients than in low‐PRDM16‐expression patients (5‐year OS, 18% vs. 34%; P = 0.002). This trend was observed more clearly among patients aged <65 years (5‐year OS, 21% vs. 50%; P = 0.001), particularly in FLT3‐ITD‐negative patients in the intermediate cytogenetic risk group (5‐year OS, 25% vs. 59%; P = 0.009). These results suggest that high PRDM16 expression is a significant predictive marker for poor prognosis in adult AML patients, similar to pediatric AML patients.
Outcomes of conception subsequent to methotrexate treatment for an unruptured ectopic pregnancy
Authors: Svirsky Ran , Ben‐Ami Ido , Berkovitch Matitiahu , Halperin Reuvit , Rozovski Uri 
Published: July 2017

AbstractObjectiveTo assess the risk of adverse pregnancy outcomes in subsequent pregnancies among women treated with methotrexate for ectopic pregnancy.MethodsIn a retrospective single‐center study, data were assessed for women treated with methotrexate for ectopic pregnancy at Asaf Harofe Medical Center, Zerifin, Israel, between May 2004 and May 2014.ResultsOverall, 226 women were treated with methotrexate for ectopic pregnancy and subsequently conceived. The median time from treatment to conception was 10 months (range 1–120 months), and 127 women conceived within 12 months of treatment. Except for early missed abortion—which affected 23 (10.2%) pregnancies—adverse pregnancy outcomes such as fetal malformations were rare. The frequency of early abortion was lowest for women who conceived within 6 months of treatment with methotrexate (3/93, 3.2%), increased between 6 and 23 months (15/83, 18.1%), and remained high thereafter (7/50, 14.0%; P=0.006).ConclusionThe frequency of fetal malformation in a subsequent pregnancy was low among women treated with methotrexate for ectopic pregnancy. The frequency of early missed abortion was lowest during the first 6 months after treatment with methotrexate.
Trunk elongation and ontogenetic changes in the axial skeleton of Triturus newts
Authors: Govedarica Petar , Cvijanović Milena , Slijepčević Maja , Ivanović Ana 
Published: July 2017

AbstractBody elongation in vertebrates can be achieved by lengthening of the vertebrae or by an increase in their number. In salamanders, longer bodies are mostly associated with greater numbers of vertebrae in the trunk or tail region. However, studies on the relative contribution of the length of single vertebra to body elongation are lacking. In this study, we focus on evolutionary and ontogenetic changes in differentiation of the trunk vertebrae and the relative contribution of individual vertebrae to trunk lengthening in Triturus newts, a monophyletic group of salamanders that shows remarkable disparity in body shape. We compared juveniles and adults of the most elongated T. dobrogicus, which has 17 trunk vertebrae, with juveniles and adults of two closely related species (T. ivanbureschi and T. anatolicus belonging to the T. karelinii species complex) representing a stout and robust morphotype with thirteen trunk vertebrae. We show that trunk vertebrae are uniform in size at the juvenile stage of both analyzed morphotypes. In adults, the trunk vertebrae of the elongated T. dobrogicus are largely uniform, while in those of T. anatolicus, the first two vertebrae differ from the remaining trunk vertebrae. There was no difference in the relative contribution of individual vertebrae to body lengthening between species or stages. We conclude that body elongation in Triturus newts is achieved by increasing the number of vertebrae but not their length.
Color discrimination errors associate with axial motor impairments in Parkinson's Disease
Authors: Bohnen Nicolaas I. , Haugen Jacob , Ridder Andrew , Kotagal Vikas , Albin Roger L. , Frey Kirk A. , Müller Martijn L.T.M. 
Published: July 2017

AbstractBackgroundVisual function deficits are more common in imbalance‐predominant compared to tremor‐predominant PD, suggesting a pathophysiological role of impaired visual functions in axial motor impairments.ObjectiveTo investigate the relationship between changes in color discrimination and motor impairments in PD while accounting for cognitive or other confounder factors.MethodsPD subjects (n = 49, age 66.7 ± 8.3 years; Hoehn & Yahr stage 2.6 ± 0.6) completed color discrimination assessment using the Farnsworth‐Munsell 100 Hue Color Vision Test, neuropsychological, motor assessments, and [11C]dihydrotetrabenazine vesicular monoamine transporter type 2 PET imaging. MDS‐UPDRS sub‐scores for cardinal motor features were computed. Timed Up & Go mobility and walking tests were assessed in 48 subjects.ResultsBivariate correlation coefficients between color discrimination and motor variables were significant only for the Timed Up & Go test (RS = 0.44, P = 0.0018) and the MDS‐UPDRS axial motor scores (RS = 0.38, P = 0.0068). Multiple regression confounder analysis using the Timed Up & Go as outcome parameter showed a significant total model (F(5,43) = 7.3, P < 0.0001) with significant regressor effects for color discrimination (standardized β = 0.32, t = 2.6, P = 0.012), global cognitive Z‐score (β = −0.33, t = −2.5, P = 0.018), duration of disease (β = 0.26, t = 1.8, P = 0.038), but not for age or striatal dopaminergic binding. The color discrimination test was also a significant independent regressor in the MDS‐UPDRS axial motor model (standardized β = 0.29, t = 2.4, P = 0.022; total model t(5,43) = 6.4, P = 0.0002).ConclusionsColor discrimination errors associate with axial motor features in PD independent of cognitive deficits, nigrostriatal dopaminergic denervation, and other confounder variables. These findings may reflect shared pathophysiology between color discrimination visual impairments and axial motor burden in PD.
Ultrasound assessment of the sural nerve in patients with neuropathic pain after ankle surgery
Authors: Rbia Nadia , Nijhuis Tim H.J. , Roukema Gert R. , Selles Ruud W. , van der Vlies Cornelis H. , Hovius Steven E.R. 
Published: July 2017

ABSTRACTIntroduction: The sural nerve may be damaged after ankle injury. The aim of our study was to determine the diagnostic utility of high‐resolution sonography in patients with ankle fractures treated by open reduction and internal fixation in whom there was a clinical suspicion of sural neuropathy. Methods: We examined the ultrasound (US) characteristics of patients with and without postsurgical sural neuropathic pain and healthy volunteers. Cross‐sectional area (CSA), echogenicity, and vascularization of the sural nerves were recorded. Results: Fourteen participants and all sural nerves were identified. CSA (P < 0.001) and vascularization (P = 0.002) were increased in symptomatic patients when compared with asymptomatic patients and healthy volunteers. There were no significant differences in nerve echogenicity (P = 0.983). Discussion: US may be a valuable tool for evaluating clinically suspected sural nerve damage after ankle stabilization surgery. Sural nerve abnormalities are seen in patients with postsurgical neuropathic pain. Muscle Nerve 57: 407–413, 2018