bluuebunny/crossref_metadata_2025 huggingface dataset:
Water toxicity assessment of Santos Bay under different climate conditions
Authors: Moreira Lucas Buruaem , Abessa Denis Moledo de Souza
Published: August 2014

Climate conditions and the movement of water masses are among the main factors that influence the destination of pollutants, acting upon transport and dispersion affecting, thus, the quality of water. Samples from Santos Bay were collected under normal conditions (08/21/2008) and during the entrance of a frontal system (08/22/2008) and tested for chronic ecotoxicity using fertilized eggs of sea urchin Lytechinus variegatus. Samples were toxic for stations near Xixová-Japuí State Park, Port of Santos, Submarine Outfall and Moela’s Island, sites related to pollution sources. Differences in climate conditions were observed and its contribution on toxicity seemed to be significant at the entrance of São Vicente estuary and Moela’s Island. At the stations in Santos Bay under influence of contamination from multiple sources such as the presence of outfall and sediments disposal from dredging, the continuous release of compounds still plays an important role in environmental quality.
Ambient measurements of biological aerosol particles near Killarney, Ireland: a comparison between real-time fluorescence and microscopy techniques
Authors: Healy D. A. , Huffman J. A. , O'Connor D. J. , Pöhlker C. , Pöschl U. , Sodeau J. R.
Published: August 2014

Abstract. Primary biological aerosol particles (PBAPs) can contribute significantly to the coarse particle burden in many environments. PBAPs can thus influence climate and precipitation systems as cloud nuclei and can spread disease to humans, animals, and plants. Measurement data and techniques for PBAPs in natural environments at high time- and size resolution are, however, sparse, and so large uncertainties remain in the role that biological particles play in the Earth system. In this study two commercial real-time fluorescence particle sensors and a Sporewatch single-stage particle impactor were operated continuously from 2 August to 2 September 2010 at a rural sampling location in Killarney National Park in southwestern Ireland. A cascade impactor was operated periodically to collect size-resolved particles during exemplary periods. Here we report the first ambient comparison of a waveband integrated bioaerosol sensor (WIBS-4) with a ultraviolet aerodynamic particle sizer (UV-APS) and also compare these real-time fluorescence techniques with results of fluorescence and optical microscopy of impacted samples. Both real-time instruments showed qualitatively similar behavior, with increased fluorescent bioparticle concentrations at night, when relative humidity was highest and temperature was lowest. The fluorescent particle number from the FL3 channel of the WIBS-4 and from the UV-APS were strongly correlated and dominated by a 3 μm mode in the particle size distribution. The WIBS FL2 channel exhibited particle modes at approx. 1 and 3 μm, and each was correlated with the concentration of fungal spores commonly observed in air samples collected at the site (ascospores, basidiospores, Ganoderma spp.). The WIBS FL1 channel exhibited variable multimodal distributions turning into a broad featureless single mode after averaging, and exhibited poor correlation with fungal spore concentrations, which may be due to the detection of bacterial and non-biological fluorescent particles. Cladosporium spp., which are among the most abundant fungal spores in many terrestrial environments, were not correlated with any of the real-time fluorescence channels, suggesting that the real-time fluorescence instruments are relatively insensitive to PBAP classes with dark, highly absorptive cell walls. Fluorescence microscopy images of cascade impactor plates showed large numbers of coarse-mode particles consistent with the morphology and weak fluorescence expected of sea salt. Some of these particles were attached to biological cells, suggesting that a marine source influenced the PBAPs observed at the site and that the ocean may be an important contributor to PBAP loadings in coastal environments.
Investigating the two-component model of solid fuel organic aerosol in London: processes, PM1 contributions, and seasonality
Authors: Young D. E. , Allan J. D. , Williams P. I. , Green D. C. , Harrison R. M. , Yin J. , Flynn M. J. , Gallagher M. W. , Coe H.
Published: August 2014

Abstract. Solid fuel emissions, including those from biomass burning, are increasing in urban areas across the European Union due to rising energy costs and government incentives to use renewable energy sources for heating. In order to help protect human health as well as to improve air quality and pollution abatement strategies, the sources of combustion aerosols, their contributions, and the processes they undergo need to be better understood. A high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was therefore deployed at an urban background site between January and February 2012 to investigate solid fuel organic aerosols (SFOA) in London. The variability of SFOA was examined and the factors governing the split between the two SFOA factors derived from positive matrix factorisation (PMF) were assessed. The concentrations of both factors were found to increase during the night and during cold periods, consistent with domestic space heating activities. The split between the two factors is likely governed predominantly by differences in burn conditions where SFOA1 best represents more efficient burns in the south and SFOA2 best represents less efficient burns in the east and west. The differences in efficiency may be due to burner types or burn phase, for example. Different fuel types and levels of atmospheric processing also likely contribute to the two factors. As the mass spectral profile of SFOA is highly variable, the findings from this study have implications for improving future source apportionment and factorisation analyses. During the winter, SFOA was found to contribute 38% to the total submicron organic aerosol (OA) mass, with SFOA2 contributing slightly more than SFOA1 (20% compared to 18%). A similar contribution of SFOA was derived for the same period from compact time-of-flight AMS (cToF-AMS), which measured for a full calendar year at the same site. The seasonality of SFOA was investigated using the year-long data set where concentrations were greatest in the autumn and winter. During the summer, SFOA contributed 11% to the organic fraction, where emissions resulted from different anthropogenic activities such as barbecues and domestic garden wood burning. The significant contribution of SFOA to total organic mass throughout the year suggests that the negative effects on health and air quality, as well as climate, are not just confined to winter as exposure to these aerosols and the associated black carbon can also occur during the summer, which may have significant implications for air-quality policies and mitigation strategies.
A multi-site intercomparison of integrated water vapour observations for climate change analysis
Authors: Van Malderen R. , Brenot H. , Pottiaux E. , Beirle S. , Hermans C. , De Mazière M. , Wagner T. , De Backer H. , Bruyninx C.
Published: August 2014

Abstract. Water vapour plays a dominant role in the climate change debate. However, observing water vapour over a climatological time period in a consistent and homogeneous manner is challenging. On one hand, networks of ground-based instruments able to retrieve homogeneous integrated water vapour (IWV) data sets are being set up. Typical examples are Global Navigation Satellite System (GNSS) observation networks such as the International GNSS Service (IGS), with continuous GPS (Global Positioning System) observations spanning over the last 15+ years, and the AErosol RObotic NETwork (AERONET), providing long-term observations performed with standardized and well-calibrated sun photometers. On the other hand, satellite-based measurements of IWV already have a time span of over 10 years (e.g. AIRS) or are being merged to create long-term time series (e.g. GOME, SCIAMACHY, and GOME-2). This study performs an intercomparison of IWV measurements from satellite devices (in the visible, GOME/SCIAMACHY/GOME-2, and in the thermal infrared, AIRS), in situ measurements (radiosondes) and ground-based instruments (GPS, sun photometer), to assess their use in water vapour trends analysis. To this end, we selected 28 sites world-wide for which GPS observations can directly be compared with coincident satellite IWV observations, together with sun photometer and/or radiosonde measurements. The mean biases of the different techniques compared to the GPS estimates vary only between −0.3 to 0.5 mm of IWV. Nevertheless these small biases are accompanied by large standard deviations (SD), especially for the satellite instruments. In particular, we analysed the impact of clouds on the IWV agreement. The influence of specific issues for each instrument on the intercomparison is also investigated (e.g. the distance between the satellite ground pixel centre and the co-located ground-based station, the satellite scan angle, daytime/nighttime differences). Furthermore, we checked if the properties of the IWV scatter plots between these different instruments are dependent on the geography and/or altitude of the station. For all considered instruments, the only dependency clearly detected is with latitude: the SD of the IWV observations with respect to the GPS IWV retrievals decreases with increasing latitude and decreasing mean IWV.
Physical controls on CH4 emissions from a newly flooded subtropical freshwater hydroelectric reservoir: Nam Theun 2
Authors: Deshmukh C. , Serça D. , Delon C. , Tardif R. , Demarty M. , Jarnot C. , Meyerfeld Y. , Chanudet V. , Guédant P. , Rode W. , Descloux S. , Guérin F.
Published: August 2014

Abstract. In the present study, we measured independently CH4 ebullition and diffusion in the footprint of an eddy covariance system (EC) measuring CH4 emissions in the Nam Theun 2 Reservoir, a recently impounded (2008) subtropical hydroelectric reservoir located in the Lao People's Democratic Republic (PDR), Southeast Asia. The EC fluxes were very consistent with the sum of the two terms measured independently (diffusive fluxes + ebullition = EC fluxes), indicating that the EC system picked up both diffusive fluxes and ebullition from the reservoir. We showed a diurnal bimodal pattern of CH4 emissions anti-correlated with atmospheric pressure. During daytime, a large atmospheric pressure drop triggers CH4 ebullition (up to 100 mmol m−2 d−1), whereas at night, a more moderate peak of CH4 emissions was recorded. As a consequence, fluxes during daytime were twice as high as during nighttime. Additionally, more than 4800 discrete measurements of CH4 ebullition were performed at a weekly/fortnightly frequency, covering water depths ranging from 0.4 to 16 m and various types of flooded ecosystems. Methane ebullition varies significantly seasonally and depends mostly on water level change during the warm dry season, whereas no relationship was observed during the cold dry season. On average, ebullition was 8.5 ± 10.5 mmol m−2 d−1 and ranged from 0 to 201.7 mmol m−2 d−1. An artificial neural network (ANN) model could explain up to 46% of seasonal variability of ebullition by considering total static pressure (the sum of hydrostatic and atmospheric pressure), variations in the total static pressure, and bottom temperature as controlling factors. This model allowed extrapolation of CH4 ebullition on the reservoir scale and performance of gap filling over four years. Our results clearly showed a very high seasonality: 50% of the yearly CH4 ebullition occurs within four months of the warm dry season. Overall, ebullition contributed 60–80% of total emissions from the surface of the reservoir (disregarding downstream emissions), suggesting that ebullition is a major pathway in young hydroelectric reservoirs in the tropics.
A comparison of three simple approaches to identify critical areas for runoff and dissolved reactive phosphorus losses
Authors: Hahn C. , Prasuhn V. , Stamm C. , Milledge D. G. , Schulin R.
Published: August 2014

Abstract. Diffuse phosphorus (P) losses are the main cause for eutrophication of surface waters in many regions. Implementing mitigation measures on critical source areas (CSAs) is seen to be the most effective way to reduce P losses. Thus, tools are needed that delineate CSAs on the basis of available data. We compared three models based on different approaches and sets of input data: the rainfall-runoff-phosphorus (RRP) model, the dominant runoff processes (DoRP) model, and the Sensitive Catchment Integrated Modeling Analysis Platform (SCIMAP). The RRP model is a parsimonious dynamic model using the topographic index and a binary soil classification to simulate discharge and P losses. The DoRP model distinguishes eight soil classes based on soil and geological maps. It does not account for topography when calculating runoff. SCIMAP assesses runoff risks solely on the basis of topography using the network index. Compared to surface runoff and soil moisture data available from a catchment in Switzerland, the RRP model and SCIMAP made better predictions than the DoRP model, suggesting that in our study area topography was more important for CSA delineation than soil data. Based on the results, we suggest improvements of SCIMAP to enable average risk predictions and the comparison of risk predictions between catchments.
Extreme storm surges: a comparative study of frequency analysis approaches
Authors: Hamdi Y. , Bardet L. , Duluc C.-M. , Rebour V.
Published: August 2014

Abstract. In France, nuclear facilities were designed around very low probabilities of failure. Nevertheless, some extreme climatic events have given rise to exceptional observed surges (outliers) much larger than other observations, and have clearly illustrated the potential to underestimate the extreme water levels calculated with the current statistical methods. The objective of the present work is to conduct a comparative study of three approaches to extreme value analysis, including the annual maxima (AM), the peaks-over-threshold (POT) and the r-largest order statistics (r-LOS). These methods are illustrated in a real analysis case study. All data sets were screened for outliers. Non-parametric tests for randomness, homogeneity and stationarity of time series were used. The shape and scale parameter stability plots, the mean excess residual life plot and the stability of the standard errors of return levels were used to select optimal thresholds and r values for the POT and r-LOS method, respectively. The comparison of methods was based on (i) the uncertainty degrees, (ii) the adequacy criteria and tests, and (iii) the visual inspection. It was found that the r-LOS and POT methods have reduced the uncertainty on the distribution parameters and return level estimates and have systematically shown values of the 100 and 500-year return levels smaller than those estimated with the AM method. Results have also shown that none of the compared methods has allowed a good fit at the right tail of the distribution in the presence of outliers. As a perspective, the use of historical information was proposed in order to increase the representativeness of outliers in data sets. Findings are of practical relevance, not only to nuclear energy operators in France, for applications in storm surge hazard analysis and flood management, but also for the optimal planning and design of facilities to withstand extreme environmental conditions, with an appropriate level of risk.
Geometric and topological approaches to significance testing in wavelet analysis
Authors: Schulte J. A. , Duffy C. , Najjar R. G.
Published: August 2014

Abstract. Geometric and topological methods are applied to significance testing in the wavelet domain. A geometric test was developed for assigning significance to pointwise significance patches in local wavelet spectra, contiguous regions of significant wavelet coefficients with respect to some noise model. This geometric significance test was found to produce results similar to an existing areawise significance test, while being more computationally flexible and efficient. The geometric significance test can be readily applied to pointwise significance patches at various pointwise significance levels in wavelet power and coherence spectra. A topological analysis of pointwise significance patches determined that holes, deficits in pointwise significance embedded in significance patches, are capable of identifying important structures, some of which are undetected by the geometric and areawise tests. The application of the new and existing significance tests to ideal time series and to the time series of the Niño 3.4 and North Atlantic Oscillation showed that the areawise and geometric tests perform similarly in ideal and geophysical settings, while the topological methods showed that the Niño 3.4 time series contains numerous phase-coherent oscillations.
Sense of Humor, Stable Affect, and Psychological Well-Being
Authors: Cann Arnie , Collette Chantal
Published: August 2014

A good sense of humor has been implicated as a quality that could contribute to psychological well-being. The mechanisms through which sense of humor might operate include helping to reappraise threats, serving as a character strength, or facilitating happiness. The current research attempts to integrate these possibilities by examining whether a good sense of humor might operate globally by helping to maintain a more stable positive affect. Stable positive affect has been shown to facilitate more effective problem solving and to build resilience. However, not all humor is adaptive humor, so we also examine the roles that different styles of humor use might play. Individual differences in humor styles were used to predict stable levels of affect. Then, in a longitudinal design, humor styles and stable affect were used to predict subsequent resilience and psychological health. The results indicated that stable affect was related to resilience and psychological well-being, and that a sense of humor that involves self-enhancing humor, humor based on maintaining a humorous perspective about one’s experiences, was positively related to stable positive affect, negatively related to stable negative affect, and was mediated through stable affect in influencing resilience, well-being and distress. Thus, while a good sense of humor can lead to greater resilience and better psychological health, the current results, focusing on stable affect, find only self-enhancing humor provides reliable benefits.
Rumination, Suicidal Ideation, and the Mediating Effect of Self-Defeating Humor
Authors: Tucker Raymond P. , Wingate LaRicka R. , Slish Meredith L. , O’Keefe Victoria M. , Cole Ashley B. , Hollingsworth David W.
Published: August 2014

Research has demonstrated that a self-defeating humor style is related to indicators of psychopathology and interpersonal dysfunction, including depression, anxiety, loneliness, thwarted belongingness, and perceived burdensomeness. The current study continued this investigation by examining how self-defeating humor is related to suicidal ideation and a ruminative response style. Analyses indicated that a self-defeating humor style was positively associated to rumination, brooding, reflection, and suicidal ideation. Results of bootstrapping analyses indicated that self-defeating humor mediated the relationship between rumination and suicidal ideation. This same effect was seen for both brooding and reflection individually. Results indicate that self-defeating humor may serve as an interpersonal means of ruminating as this humor style involves consistent focus on perceived flaws and weaknesses. The assessment of this humor style may provide additional information about the maintenance of suicidal thinking.
Affective Style, Humor Styles and Happiness
Authors: Ford Thomas E. , McCreight Katelyn A. , Richardson Kyle
Published: August 2014

The present study examined the relationships between dispositional approach and avoidance motives, humor styles, and happiness. In keeping with previous research, approach motives and the two positive humor styles (self-enhancing and affiliative) positively correlated with happiness, whereas avoidance motives and the two negative humor styles (self-defeating and aggressive) negatively correlated with happiness. Also, we found support for three new hypotheses. First, approach motives correlated positively with self-enhancing and affiliative humor styles. Second, avoidance motives correlated positively with self-defeating humor style, and third, the positive relationship between approach motives and happiness was mediated by self-enhancing humor style.
Research on the Role of Humor in Well-Being and Health: An Interview With Professor Arnie Cann
Authors: Cann Arnie , Kuiper Nicholas A.
Published: August 2014

In this interview, Dr. Arnie Cann discusses his research and views on the ubiquitous role of humor in psychological health and well-being. The interview begins with Professor Cann recounting how he originally became interested in studying humor. He then reflects on the main findings associated with the wide variety of humor-related studies he has conducted over the years. In doing so, Dr. Cann provides suggestions and ideas for further research investigating the role of humor in health and well-being. Specific topic areas discussed include the use of humor in the workplace and other social domains, personality approaches to humor, humor and interpersonal processes, humor and psychopathology, and humor’s role in dealing with stress and well-being. One of the prominent themes in this interview is the clear recognition of sense of humor as a multi-dimensional construct that includes various components that may either be beneficial or detrimental to well-being. A further important theme is the major distinction between humor as an inherent personality construct versus humor that results from exposure to stimuli (e.g., a comedy film). Comments are also provided by Dr. Cann on how the positive affect stemming from humor may be of particular benefit to the individual. Also discussed is the recent move to more fully integrate contemporary humor research with positive psychology approaches. The interview concludes with Dr. Cann providing several recommendations regarding future theorizing and research on the role of humor in psychological well-being.
Urbanization and the carbon cycle: Current capabilities and research outlook from the natural sciences perspective
Authors: Hutyra Lucy R. , Duren Riley , Gurney Kevin R. , Grimm Nancy , Kort Eric A. , Larson Elisabeth , Shrestha Gyami
Published: August 2014

This paper explores the urban carbon cycle from the natural sciences perspective, identifying key knowledge gaps and priority areas for future research. The combination of large, concentrated carbon fluxes and rapid change makes cities key elements of the carbon cycle and offers the potential for them to serve as “first responders” for climate action. Estimates of urban‐scale carbon fluxes are significantly more uncertain than at larger spatial scales, in part because past studies have mostly avoided local/urban scales where the mix of anthropogenic and natural fluxes is complex and difficult to observationally isolate. To develop effective emission reduction policies, we need to understand emission sources and how they may be changing. Such improved quantification and understanding of underlying processes at the urban scale will not only provide policy‐relevant information and improve the understanding of urban dynamics and future scenarios, but will also translate into better global‐scale anthropogenic flux estimates, and advance our understanding of carbon cycle and climate feedbacks across multiple scales. Understanding the relationship between urbanization and urban carbon flows requires intellectual integration with research communities beyond the natural sciences. Cities can serve as interdisciplinary process laboratories that are sufficiently constrained in both spatial and governance scale to support truly integrated research by the natural sciences, social sciences, and engineering. A thoughtfully crafted science research agenda that is grounded in sustained, dense observations relevant to estimating urban carbon fluxes and their controlling processes and is focused on a statistically significant sample of cities will advance our understanding of the carbon cycle.
Using Real‐World and Standardized Spatial Imagery Tasks: Convergence, Imagery Realism, and Gender Differences
Authors: Diehl Virginia A.
Published: August 2014

Can realistic spatial scenarios be used to measure spatial mental imagery? Can people accurately evaluate their spatial imagery? Does gender moderate the relationship between performance on realistic spatial imagery tasks and ratings of imagery realism? Forty‐two female and 31 male undergraduates first rated the realism of their images after reading spatial scenarios based on actual spatial tasks. In phase 2, they solved closely related spatial scenario problems, and then completed the VZ‐2 Paper Folding test. Performance on realistic spatial scenarios predicted performance on the VZ‐2. Men's evaluation of their spatial imagery realism predicted their actual spatial performance, but women's did not. More task experience was positively related to more realistic images and higher scores on the VZ‐2. These results were generally consistent with those found with more artificial stimulus materials, but also demonstrated the importance of considering gender differences in spatial problem strategy and/or rating scale interpretation. Copyright © 2014 John Wiley & Sons, Ltd.
Use of a Desymmetrized meso Molecule as a Chiral Ligand: Development of Chiral N‐Heterocyclic Carbene Ligands for Asymmetric Allylic Arylations with Grignard Reagents
Authors: Ando Shin , Matsunaga Hirofumi , Ishizuka Tadao
Published: August 2014

The desymmetrization of a meso molecule was used for the development of a chiral N‐heterocyclic carbene (NHC) ligand. This chiral NHC was then successfully applied to a copper‐catalyzed asymmetric allylic arylation with Grignard reagents. The level of stereocontrol was improved to 89 % ee via derivatization studies. The synthesized copper catalyst was effective at the level of 0.05 mol % loading for gram‐scale reactions.
Selective Formation and Unusual Reactivity of Tetraarsabicyclo[1.1.0]butane Complexes
Authors: Schwarzmaier Christoph , Timoshkin Alexey Y. , Balázs Gábor , Scheer Manfred
Published: August 2014

The selective formation of the dinuclear butterfly complexes [{Cp′′′Fe(CO)2}2(μ,η1:1‐E4)] (E=P (1 a), As (1 b)) and [{Cp*Cr(CO)3}2(μ,η1:1‐E4)] (E=P (2 a), As (2 b)) as new representatives of this rare class of compounds was found by reaction of E4 with the corresponding dimeric carbonyl complexes. Complexes 1 b and 2 b are the first As4 butterfly compounds with a bridging coordination mode. Moreover, first studies regarding the reactivity of 1 b and 2 b are presented, revealing the formation of the unprecedented As8 cuneane complexes [{Cp′′′Fe(CO)2}2{Cp′′′Fe(CO)}2(μ4,η1:1:2:2‐As8)] (3 b) and [{Cp*Cr(CO)3}4(μ4,η1:1:1:1‐As8)] (4). The compounds are fully characterized by NMR and IR spectroscopy as well as by X‐ray structure analysis. In addition, DFT calculations give insight into the transformation pathway from the E4 butterfly to the corresponding cuneane structural motif.
Polymorphic calcium carbonate phases as adsorbents for allergens in natural rubber latex
Authors: Petrack Janina , Vucak Marijan , Nover Christoph , Epple Matthias
Published: August 2014

Natural rubber latex contains different allergenic proteins and peptides that restrict its application in consumer products. Small mineral particles have a comparatively high specific surface area and are therefore well suited to adsorb such biomolecules. The adsorption of such biomolecules onto different polymorphic phases of calcium carbonate, i.e., calcite, aragonite, and vaterite, was quantitatively determined, both from solution as well as from cured natural rubber latex. All phases were able to adsorb the allergens, with slight differences between the different allergens. Desorption experiments showed differences between the allergens of natural rubber latex, but only small differences between the polymorphic phases of calcium carbonate. The release of the allergens from latex objects with incorporated calcium carbonate particles showed that a retention of allergens is possible by adding calcium carbonate as a filler material. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41271.
An innovative material based on natural rubber and leather tannery waste to be applied as antistatic flooring
Authors: Ruiz Marcos R. , Budemberg Eduardo R. , da Cunha Giovanni P. , Bellucci Felipe S. , da Cunha Helder N. , Job Aldo E.
Published: August 2014

In recent decades, the production chain of beef and bovine leather has grown significantly because of an increase in the world's population and improved access to consumption. However, the generation of waste derived from this sector has grown simultaneously, and consequently, improved ways of adding value, reusing, and disposing these waste materials are being sought. In this article, we present a new and innovative composite material based on vulcanized natural rubber (NR), carbon black (CB), and leather waste (NR/CB/leather). The NR/CB/leather composites were prepared by thermal compression with 60 phr of CB and 60 or 80 phr of leather waste. In accordance with Brazilian sanitary laws, we exposed these composites for 24 h to bleach (B) and a disinfectant with the aim of simulating a true everyday cleaning use. The deconvolution of the impedance semicircles was carried out, and two relaxation phenomena around linear relaxation frequencies of about 105 and 106 Hz were found and associated mainly with charge carriers from CB and leather waste. With the addition of leather, the electrical conductivity of the composites increased two orders of magnitude from 5.70 × 10−6 for the NR/CB to 7.97 × 10−4 S/cm for NR/CB/leather‐60 phr B. These results point to the possibility of using these composites as an antistatic flooring once they exhibit acceptable values of electrical conductivity and once they withstand, from the structural, morphological, and electrical point of view, exposure to sanitizing agents. Furthermore, the production of these composites will add value to and enable an environmentally acceptable disposal of leather waste. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41297.
Regenerated cellulose fibers as impact modifier in long jute fiber reinforced polypropylene composites: Effect on mechanical properties, morphology, and fiber breakage
Authors: Ranganathan Nalini , Oksman Kristiina , Nayak Sanjay K. , Sain Mohini
Published: August 2014

Polypropylene/jute fiber (PP‐J) composites with various concentrations of viscose fibers (VF) as impact modifiers and maleated polypropylene (MAPP) as a compatibilizer have been studied. The composite materials were manufactured using direct long fiber thermoplastic (D‐LFT) extrusion and compression molding. The effect of fiber length, after the extrusion process, on composites mechanical performance and toughness was investigated. The results showed that the incorporation of soft and tough VF on the PP‐J improved the energy absorption of the composites. The higher impact strength was found with the addition of 10 wt % of the impact modifier, but the increased concentration of the impact modifier affected the tensile and flexural properties negatively. Similarly, HDT values were reduced with addition of viscose fibers whereas the addition of 2 wt % of maleated polypropylene significantly improved the overall composite properties. The microscopic analysis clearly demonstrated longer fiber pullouts on the optimized impact modified composite. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41301.
Carbon dioxide switchable polymer surfactant copolymerized with 2‐(dimethylamino)ethyl methacrylate and butyl methacrylate as a heavy‐oil emulsifier
Authors: Lu Hongsheng , Zhou Zheng , Jiang Jifeng , Huang Zhiyu
Published: August 2014

A CO2‐switchable polymer surfactant was synthesized with 2‐(dimethylamino)ethyl methacrylate and butyl methacrylate. The conductivity, ζ potential, and particle size change illustrated the switchability of the surfactant, and this change could be repeated. Its surface tension decreased sharply when the sample was bubbled with CO2; this indicated the enhancement of the surface activity. In the heavy‐oil emulsion with a surfactant concentration of 8 g/L, the viscosity almost reached the highest stability. When CO2 overflowed the emulsion, it became unstable when the temperature beyond 40°C. The emulsion had a nice resistance to inorganic salt, which was maintained stably even when the concentration of NaCl was as high as 90,000 ppm. The emulsion could later be broken by the removal of CO2. Its hydration rate was over 22 times faster than that in the presence of CO2. The amount of residual oil in water was only about 53.84 ppm; this showed a good demulsification ability. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41307.
Preparation and properties of styrene‐butadiene rubber nanocomposites blended with carbon black‐graphene hybrid filler
Authors: Zhang Hongmei , Wang Chunwei , Zhang Yong
Published: August 2014

Graphene has become an attractive reinforcing filler for rubber materials, but its dispersion in rubber is still a big challenge. In this work, a novel carbon black‐reduced graphene (CB‐RG) hybrid filler was fabricated and blended with styrene‐butadiene rubber (SBR) via simple two‐roll mill mixing. The prepared CB‐RG hybrids had a microstructure with small CB agglomerates adsorbed onto graphene surfaces. CB acted as a barrier preventing the RG sheets from restacking even after drying. Homogeneous dispersion of graphene sheets in SBR matrix was observed by the mechanical mixing method based on the application of the CB‐RG hybrid fillers. Dynamic mechanical analysis showed that Tg of the SBR/CB‐RG blend was higher than that of the SBR/CB blend indicating strong interfacial interactions between RG and SBR due to the high surface area of graphene and the π‐π interaction between SBR and graphene. The tensile properties of SBR/CB‐RG composites improved significantly and the volume resistivity decreased compared with the SBR/CB blends. The thermal stability of SBR composites filled with CB and CB‐RG showed slight difference. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41309.
High strength poly(vinyl alcohol) films obtained by drying and then stretching freeze/thaw cycled gel
Authors: Fukumori Taishi , Nakaoki Takahiko
Published: August 2014

The mechanical properties of stretched poly(vinyl alcohol) (PVA), which is formed by stretching a film prepared from a freeze/thaw cycled gel, were investigated as a function of the stretching ratio. The tensile strength and Young's modulus of 800% stretched PVA annealed at 130°C were 3.4 and 119 GPa, respectively. These values were much higher than those for a PVA film prepared without freeze/thaw cycling. For a film stretched more than 600% before annealing, two melting peaks, assignable to folded and extended chain crystals, were observed around 220°C and 230°C, respectively. This indicates that a shish‐kebab structure is formed as the stretching ratio increases. After annealing at 130°C, the folded‐chain crystal transformed to an extended‐chain crystal if an extended‐chain crystal was present in the stretched film before annealing. High tensile strength and Young's modulus after annealing were due to the formation of extended‐chain crystal. Therefore, the presence of extended‐chain crystal for annealing is important to provide good mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41318.
Traffic jam in the primitive streak: The role of defective mesoderm migration in birth defects
Authors: Herion Nils J. , Salbaum J. Michael , Kappen Claudia
Published: August 2014

Gastrulation is the process in which the three germ layers are formed that contribute to the formation of all major tissues in the developing embryo. We here review mouse genetic models in which defective gastrulation leads to mesoderm insufficiencies in the embryo. Depending on severity of the abnormalities, the outcomes range from incompatible with embryonic survival to structural birth defects, such as heart defects, spina bifida, or caudal dysgenesis. The combined evidence from the mutant models supports the notion that these congenital anomalies can originate from perturbations of mesoderm specification, epithelial–mesenchymal transition, and mesodermal cell migration. Knowledge about the molecular pathways involved may help to improve strategies for the prevention of major structural birth defects. Birth Defects Research (Part A) 100:608–622, 2014. © 2014 Wiley Periodicals, Inc.
Scaled‐up manufacturing of recombinant antibodies produced by plant cells in a 200‐L orbitally‐shaken disposable bioreactor
Authors: Raven Nicole , Rasche Stefan , Kuehn Christoph , Anderlei Tibor , Klöckner Wolf , Schuster Flora , Henquet Maurice , Bosch Dirk , Büchs Jochen , Fischer Rainer , Schillberg Stefan
Published: August 2014

Tobacco BY‐2 cells have emerged as a promising platform for the manufacture of biopharmaceutical proteins, offering efficient protein secretion, favourable growth characteristics and cultivation in containment under a controlled environment. The cultivation of BY‐2 cells in disposable bioreactors is a useful alternative to conventional stainless steel stirred‐tank reactors, and orbitally‐shaken bioreactors could provide further advantages such as simple bag geometry, scalability and predictable process settings. We carried out a scale‐up study, using a 200‐L orbitally‐shaken bioreactor holding disposable bags, and BY‐2 cells producing the human monoclonal antibody M12. We found that cell growth and recombinant protein accumulation were comparable to standard shake flask cultivation, despite a 200‐fold difference in cultivation volume. Final cell fresh weights of 300–387 g/L and M12 yields of ∼20 mg/L were achieved with both cultivation methods. Furthermore, we established an efficient downstream process for the recovery of M12 from the culture broth. The viscous spent medium prevented clarification using filtration devices, but we used expanded bed adsorption (EBA) chromatography with SP Sepharose as an alternative for the efficient capture of the M12 antibody. EBA was introduced as an initial purification step prior to protein A affinity chromatography, resulting in an overall M12 recovery of 75–85% and a purity of >95%. Our results demonstrate the suitability of orbitally‐shaken bioreactors for the scaled‐up cultivation of plant cell suspension cultures and provide a strategy for the efficient purification of antibodies from the BY‐2 culture medium. Biotechnol. Bioeng. 2015;112: 308–321. © 2014 Wiley Periodicals, Inc.
Validation of operant social motivation paradigms using BTBR T+tf/J and C57BL/6J inbred mouse strains
Authors: Martin Loren , Sample Hannah , Gregg Michael , Wood Caleb
Published: August 2014

Background

As purported causal factors are identified for autism spectrum disorder (ASD), new assays are needed to better phenotype animal models designed to explore these factors. With recent evidence suggesting that deficits in social motivation are at the core of ASD behavior, the development of quantitative measures of social motivation is particularly important. The goal of our study was to develop and validate novel assays to quantitatively measure social motivation in mice.

Methods

In order to test the validity of our paradigms, we compared the BTBR strain, with documented social deficits, to the prosocial C57BL/6J strain. Two novel conditioning paradigms were developed that allowed the test mouse to control access to a social partner. In the social motivation task, the test mice lever pressed for a social reward. The reward contingency was set on a progressive ratio of reinforcement and the number of lever presses achieved in the final trial of a testing session (breakpoint) was used as an index of social motivation. In the valence comparison task, motivation for a food reward was compared to a social reward. We also explored activity, social affiliation, and preference for social novelty through a series of tasks using an ANY‐Maze video‐tracking system in an open‐field arena.

Results

BTBR mice had significantly lower breakpoints in the social motivation paradigm than C57BL/6J mice. However, the valence comparison task revealed that BTBR mice also made significantly fewer lever presses for a food reward.

Conclusions

The results of the conditioning paradigms suggest that the BTBR strain has an overall deficit in motivated behavior. Furthermore, the results of the open‐field observations may suggest that social differences in the BTBR strain are anxiety induced.
Acetylation‐dependent regulation of essential iPS‐inducing factors: a regulatory crossroad for pluripotency and tumorigenesis
Authors: Dai Xiangpeng , Liu Pengda , Lau Alan W. , Liu Yueyong , Inuzuka Hiroyuki
Published: August 2014

Induced pluripotent stem (iPS) cells can be generated from somatic cells by coexpression of four transcription factors: Sox2, Oct4, Klf4, and c‐Myc. However, the low efficiency in generating iPS cells and the tendency of tumorigenesis hinder the therapeutic applications for iPS cells in treatment of human diseases. To this end, it remains largely unknown how the iPS process is subjected to regulation by upstream signaling pathway(s). Here, we report that Akt regulates the iPS process by modulating posttranslational modifications of these iPS factors in both direct and indirect manners. Specifically, Akt directly phosphorylates Oct4 to modulate the Oct4/Sox2 heterodimer formation. Furthermore, Akt either facilitates the p300‐mediated acetylation of Oct4, Sox2, and Klf4, or stabilizes Klf4 by inactivating GSK3, thus indirectly modulating stemness. As tumorigenesis shares possible common features and mechanisms with iPS, our study suggests that Akt inhibition might serve as a cancer therapeutic approach to target cancer stem cells.
Bivalirudin versus unfractionated heparin for residual thrombus burden: A frequency‐domain optical coherence tomography study
Authors: Vergallo Rocco , Joye Russell , Barlis Peter , Jia Haibo , Tian Jinwei , Soeda Tsunenari , Minami Yoshiyasu , Hu Sining , Dauerman Harold L. , Toma Catalin , Chan James , Lee Hang , Biasucci Luigi Marzio , Crea Filippo , Jang Ik‐Kyung
Published: August 2014

Objectives

This study aimed to compare the effect of bivalirudin and unfractionated heparin (UFH) on residual thrombus burden assessed by frequency‐domain optical coherence tomography (FD‐OCT), and on angiographic indices of microvascular obstruction (MVO).

Background

The efficacy of bivalirudin to inhibit thrombus formation inside the stent during percutaneous coronary interventions (PCI) as compared to UFH is unknown.

Methods

Sixty patients with coronary artery disease who underwent post‐PCI FD‐OCT were studied, including 20 patients treated with bivalirudin and 40 control patients treated with UFH, matched by clinical presentation, stent characteristics, and periprocedural medications. In‐stent thrombus volume, thrombus score (number of quadrants with thrombus), and thrombus type (white/red) were assessed by FD‐OCT. Thrombolysis in myocardial infarction (TIMI) flow grade, corrected TIMI frame count (cTFC), and Quantitative Blush Evaluator (QuBE) score were recorded.

Results

Patients treated with bivalirudin showed similar thrombus volume (0.14 mm3 [0.00–0.88] vs. 0.13 mm3 [0.00–0.63], P = 0.962), thrombus score (10 [0–25] vs. 8 [0–21], P = 0.849) and thrombus length (1.70 mm [0.00–4.10] vs. 1.40 mm [0.00–4.05], P = 0.968], as compared with patients treated with UFH. Patients in the bivalirudin group showed lower proportion of white thrombus (55.5% vs. 78.6%, P = 0.016). There was no significant difference in TIMI flow grade, cTFC, and QuBE score between the two groups.

Conclusions

The present study showed similar residual thrombus burden and angiographic indices of MVO immediately after PCI between patients treated with bivalirudin and those treated with UFH. © 2014 Wiley Periodicals, Inc.
Impact of coronary artery disease on left ventricular ejection fraction recovery following transcatheter aortic valve implantation
Authors: Freixa Xavier , Chan Jason , Bonan Raoul , Ibrahim Ragui , Lamarche Yoan , Demers Philippe , Basmadjian Arsène , Ibrahim Réda , Cartier Raymond , Asgar Anita W.
Published: August 2014

Objectives

The objective of the present study was to assess if the presence and severity of CAD is associated with decreased LVEF recovery after TAVI.

Background

Coronary artery disease (CAD) and low left ventricular ejection fraction (LVEF) are common findings in patients undergoing transcatheter aortic valve implantation (TAVI). The impact of CAD on LVEF recovery after TAVI has not been specifically evaluated.

Methods

All patients with LVEF≤50% who underwent TAVI between March 2006 and May 2012 were included in the study. The presence and severity of coronary artery disease was measured using the Duke Myocardial Jeopardy Score (DMJS). A DMJS = 0 corresponds to patients without CAD or complete revascularization and a DMJS > 0 to those with incomplete revascularization. LVEF recovery was assessed by transthoracic echocardiography, measuring the change in LVEF from baseline to 3‐months post‐TAVI. Myocardial viability was evaluated in a subgroup of patients using cardiac magnetic resonance (CMR) imaging pre‐TAVI.

Results

Fifty‐six patients were included in the study. Twenty‐eight patients (50%) had a DMJS > 0. At 3 months, patients with incomplete revascularization (DMJS > 0) demonstrated less LVEF recovery post‐TAVI (2.0 ± 9.2% versus 11.7 ± 8.9% if DMJS = 0; P = 0.001). On multivariate analysis, DMJS and presence of significant delayed‐enhancement were found to be independent predictors of LVEF recovery. Patients with incomplete revascularization exhibited a worse prognosis with higher mortality at 30‐days (22.2% versus 0% if DMJS = 0; P = 0.010) and 1‐year (25.9% versus 3.5% if DMJS = 0; P = 0.019).

Conclusions

The present study demonstrates an independent association between incomplete revascularization and decreased LVEF recovery in patients with left ventricular dysfunction undergoing TAVI for severe aortic stenosis. © 2014 Wiley Periodicals, Inc.
Shortcut Evaluation of Chemical Carbon Dioxide Utilization Processes
Authors: Müller Karsten , Arlt Wolfgang
Published: August 2014

Chemical utilization of carbon dioxide seems to be an attractive option for the mitigation of greenhouse gas emissions. However, the respective processes themselves cause substantial greenhouse gas emissions. To achieve a good CO2 balance, it is necessary not only to fix carbon but also to do this efficiently in terms of reactant supply and energy demand. An evaluation of the CO2 balance requires detailed process simulation for the utilization reaction and the supply chain. To allow a quick evaluation of the potential to mitigate emissions, a number of estimation methods are presented.