bluuebunny/crossref_metadata_2025 huggingface dataset:
Fractionation of sulfur isotopes during heterogeneous oxidation of SO2 on sea salt aerosol: a new tool to investigate non-sea salt sulfate production in the marine boundary layer
Authors: Harris E. , Sinha B. , Hoppe P. , Foley S. , Borrmann S.
Published: May 2012

Abstract. The oxidation of SO2 to sulfate on sea salt aerosols in the marine environment is highly important because of its effect on the size distribution of sulfate and the potential for new particle nucleation from H2SO4 (g). However, models of the sulfur cycle are not currently able to account for the complex relationship between particle size, alkalinity, oxidation pathway and rate – which is critical as SO2 oxidation by O3 and Cl catalysis are limited by aerosol alkalinity, whereas oxidation by hypohalous acids and transition metal ions can continue at low pH once alkalinity is titrated. We have measured 34S/32S fractionation factors for SO2 oxidation in sea salt, pure water and NaOCl aerosol, as well as the pH dependency of fractionation. Oxidation of SO2 by NaOCl aerosol was extremely efficient, with a reactive uptake coefficient of ≈0.5, and produced sulfate that was enriched in 32S with αOCl = 0.9882±0.0036 at 19 °C. Oxidation on sea salt aerosol was much less efficient than on NaOCl aerosol, suggesting alkalinity was already exhausted on the short timescale of the experiments. Measurements at pH = 2.1 and 7.2 were used to calculate fractionation factors for each step from SO2(g) → multiple steps → SOOCl2−. Oxidation on sea salt aerosol resulted in a lower fractionation factor than expected for oxidation of SO32− by O3 (αseasalt = 1.0124±0.0017 at 19 °C). Comparison of the lower fractionation during oxidation on sea salt aerosol to the fractionation factor for high pH oxidation shows HOCl contributed 29% of S(IV) oxidation on sea salt in the short experimental timescale, highlighting the potential importance of hypohalous acids in the marine environment. The sulfur isotope fractionation factors measured in this study allow differentiation between the alkalinity-limited pathways – oxidation by O3 and by Cl catalysis (α34 = 1.0163±0.0018 at 19 °C in pure water or 1.0199±0.0024 at pH = 7.2) – which favour the heavy isotope, and the alkalinity non-limited pathways – oxidation by transition metal catalysis (α34 = 0.9905±0.0031 at 19 °C, Harris et al., 2012a) and by hypohalites (α34 = 0.9882±0.0036 at 19 °C) – which favour the light isotope. In combination with field measurements of the oxygen and sulfur isotopic composition of SO2 and sulfate, the fractionation factors presented in this paper may be capable of constraining the relative importance of different oxidation pathways in the marine boundary layer.
Global emission estimates and radiative impact of C4F10, C5F12, C6F14, C7F16 and C8F18
Authors: Ivy D. J. , Rigby M. , Baasandorj M. , Burkholder J. B. , Prinn R. G.
Published: May 2012

Abstract. Global emission estimates based on new atmospheric observations are presented for the acylic high molecular weight perfluorocarbons (PFCs): decafluorobutane (C4F10), dodecafluoropentane (C5F12), tetradecafluorohexane (C6F14), hexadecafluoroheptane (C7F16) and octadecafluorooctane (C8F18). Emissions are estimated using a 3-dimensional chemical transport model and an inverse method that includes a growth constraint on emissions. The observations used in the inversion are based on newly measured archived air samples that cover a 39-yr period, from 1973 to 2011, and include 36 Northern Hemispheric and 46 Southern Hemispheric samples (Ivy et al., 2012). The derived emission estimates show that global emission rates were largest in the 1980s and 1990s for C4F10 and C5F12, and in the 1990s for C6F14,C7F16 and C8F18. After a subsequent decline, emissions have remained relatively stable, within 20%, for the last 5 yr. Bottom-up emission estimates are available from the Emission Database for Global Atmospheric Research version 4.2 (EDGARv4.2) for C4F10, C5F12, C6F14 and C7F16, and inventories of C4F10, C5F12 andC6F14 are reported to the United Nations' Framework Convention on Climate Change (UNFCCC) by Annex 1 countries that have ratified the Kyoto Protocol. The atmospheric measurement based emission estimates are 20 times larger than EDGARv4.2 for C4F10 and over three orders of magnitude for C5F12. The derived emission estimates for C6F14 largely agree with the bottom-up estimates from EDGARv4.2. Moreover, the C7F16 emission estimates are comparable to those of EDGARv4.2 at their peak in the 1990s, albeit significant underestimation for the other time periods. There are no bottom-up emission estimates for C8F18, thus the emission rates reported here are the first for C8F18. The reported inventories for C4F10, C5F12 and C6F14 to UNFCCC are five to ten times lower than those estimated in this study. In addition, we present measured infrared absorption spectra for C7F16 and C8F18, and estimate their radiative efficiencies and global warming potentials (GWPs). We find that C8F18's radiative efficiency is similar to trifluoromethyl sulfur pentafluoride's (SF5CF3) at 0.57 W m−2 ppb−1, which is the highest radiative efficiency of any measured atmospheric species. Using the 100-yr time horizon GWPs, the high molecular weight perfluorocarbons studied here contributed up to 15.4% of the total PFC emissions in CO2 equivalents in 1997 and 6% of the total PFC emissions in 2009.
The composition and flux of particulate and dissolved carbohydrates from the Rhone River into the Mediterranean Sea
Authors: Panagiotopoulos C. , Sempéré R. , Para J. , Raimbault P. , Rabouille C. , Charrière B.
Published: May 2012

Abstract. Carbohydrates are important components of the carbon cycle and may be used as indicators of the origin and the diagenetic status of marine and terrestrial organic matter. Nevertheless, comprehensive studies of both particulate (PCHO) and dissolved (DCHO) carbohydrates in rivers are scarce, and the seasonal and interannual variability of these compounds in relationship to the bulk particulate (POM) and dissolved organic matter (DOM) is largely unknown. For the period 2007–2009, we sampled once per month POM and DOM and measured the total suspended matter (TSM), POM, DOM, PCHO, and DCHO for the Rhône River, which flows into the Mediterranean Sea. Using these measurements, we estimated for the above parameters annual fluxes for the period 2007–2009. The estimated carbohydrate fluxes averaged 0.064 ± 0.026 × 1010 moles C yr−1 for PCHO and 0.042 ± 0.008 × 1010 moles C yr−1 DCHO, representing 6 % and 7 % of the annual flux of POC and DOC, respectively. During flood and low-water periods, POM variations were reflected into the PCHO pool, whereas this was not observed for DOC and DCHO, indicating a decoupling between particulate and dissolved organic matter. Our results also showed that flood and low-water periods may be differentiated using the ratios PCHO/DCHO and POC/DOC, which had a significant relationship. Based on the carbohydrate abundances in both the PCHO and DCHO pools, we conclude that this material mainly derives from allochthonous sources (vascular plants, bacteria and soils). Moreover, during flood events, an enrichment in mannose in POM was observed, probably reflecting an angiosperm source (leaves or grasses). By expanding our results to the northwestern Mediterranean Sea (Gulf of Lions), we found that the total organic carbon (TOC) fluxes of the Rhône River accounted for ~1 % of the standing stock of seawater TOC. Considering that glucose is the most abundant carbohydrate in both particulate and dissolved organic matter pools (~33 %), its annual flux in the northwestern Mediterranean Sea was estimated to 3.8 × 108 moles glucose.
Estimating 750 years of temperature variations and uncertainties in the Pyrenees by tree-ring reconstructions and climate simulations
Authors: Dorado Liñán I. , Büntgen U. , González-Rouco F. , Zorita E. , Montávez J. P. , Gómez-Navarro J. J. , Brunet M. , Heinrich I. , Helle G. , Gutiérrez E.
Published: May 2012

Abstract. Past temperature variations are usually inferred from proxy data or estimated using general circulation models. Comparisons between climate estimations derived from proxy records and from model simulations help to better understand mechanisms driving climate variations, and also offer the possibility to identify deficiencies in both approaches. This paper presents regional temperature reconstructions based on tree-ring maximum density series in the Pyrenees, and compares them with the output of global simulations for this region and with regional climate model simulations conducted for the target region. An ensemble of 24 reconstructions of May-to-September regional mean temperature was derived from 22 maximum density tree-ring site chronologies distributed over the larger Pyrenees area. Four different tree-ring series standardization procedures were applied, combining two detrending methods: 300-yr spline and the regional curve standardization (RCS). Additionally, different methodological variants for the regional chronology were generated by using three different aggregation methods. Calibration verification trials were performed in split periods and using two methods: regression and a simple variance matching. The resulting set of temperature reconstructions was compared with climate simulations performed with global (ECHO-G) and regional (MM5) climate models. The 24 variants of May-to-September temperature reconstructions reveal a generally coherent pattern of inter-annual to multi-centennial temperature variations in the Pyrenees region for the last 750 yr. However, some reconstructions display a marked positive trend for the entire length of the reconstruction, pointing out that the application of the RCS method to a suboptimal set of samples may lead to unreliable results. Climate model simulations agree with the tree-ring based reconstructions at multi-decadal time scales, suggesting solar variability and volcanism as the main factors controlling preindustrial mean temperature variations in the Pyrenees. Nevertheless, the comparison also highlights differences with the reconstructions, mainly in the amplitude of past temperature variations and in the 20th century trends. Neither proxy-based reconstructions nor model simulations are able to perfectly track the temperature variations of the instrumental record, suggesting that both approximations still need further improvements.
The impact of different glacial boundary conditions on atmospheric dynamics and precipitation in the North Atlantic region
Authors: Hofer D. , Raible C. C. , Dehnert A. , Kuhlemann J.
Published: May 2012

Abstract. Using a highly resolved atmospheric general circulation model, the impact of different glacial boundary conditions on precipitation and atmospheric dynamics in the North Atlantic region is investigated. Six 30-yr time slice experiments of the Last Glacial Maximum at 21 thousand years before the present (ka BP) and of a less pronounced glacial state – the Middle Weichselian (65 ka BP) – are compared to analyse the sensitivity to changes in the ice sheet distribution, in the radiative forcing and in the prescribed time-varying sea surface temperature and sea ice, which are taken from a lower-resolved, but fully coupled atmosphere-ocean general circulation model. The strongest differences are found for simulations with different heights of the Laurentide ice sheet. A high surface elevation of the Laurentide ice sheet leads to a southward displacement of the jet stream and the storm track in the North Atlantic region. These changes in the atmospheric dynamics generate a band of increased precipitation in the mid-latitudes across the Atlantic to southern Europe in winter, while the precipitation pattern in summer is only marginally affected. The impact of the radiative forcing differences between the two glacial periods and of the prescribed time-varying sea surface temperatures and sea ice are of second order importance compared to the one of the Laurentide ice sheet. They affect the atmospheric dynamics and precipitation in a similar but less pronounced manner compared with the topographic changes.
Technology and human purpose: the problem of solids transport on the earth's surface
Authors: Haff P. K.
Published: May 2012

Abstract. Displacement of mass of limited deformability ("solids") on the Earth's surface is opposed by friction and (the analog of) form resistance – impediments relaxed by rotational motion, self-powering of mass units, and transport infrastructure. These features of solids transport first evolved in the biosphere prior to the emergence of technology, allowing slope-independent, diffusion-like motion of discrete objects as massive as several tons, as illustrated by animal foraging and movement along game trails. However, high-energy-consumption technology powered by fossil fuels required a mechanism that could support advective transport of solids, i.e., long-distance, high-volume, high-speed, unidirectional, slope independent transport across the land surface of materials like coal, containerized fluids, and minerals. Pre-technology nature was able to sustain large-scale, long-distance solids advection only in the limited form of piggybacking on geophysical flows of water (river sediment) and air (dust). The appearance of a generalized mechanism for advection of solids independent of fluid flows and gravity appeared only upon the emergence of human purpose. Purpose enables solids advection by, in effect, enabling a simulated continuous potential gradient, otherwise lacking, between discrete and widely separated fossil-fuel energy sources and sinks. Invoking purpose as a mechanism in solids advection is an example of the need to import anthropic principles and concepts into the language and methodology of modern Earth system dynamics. As part of the emergence of a generalized solids advection mechanism, several additional transport requirements necessary to the function of modern large-scale technological systems were also satisfied. These include spatially accurate delivery of advected payload, targetability to essentially arbitrarily located destinations (such as cities), and independence of structure of advected payload from transport mechanism. The latter property enables the transport of an onboard power supply and delivery of persistent-memory, high-information-content payload, such as technological artifacts ("parts").
Which type of slope gradient should be used to determine flow-partition proportion in multiple-flow-direction algorithms – tangent or sine?
Authors: Zhan L.-J. , Qin C.-Z. , Zhu A.-X.
Published: May 2012

Abstract. This paper revisits the tangent expression for the slope gradient (tan β) used in the general flow-partition function in multiple-flow-direction (MFD) algorithms. The deduction of the flow-partition function performed here based on hydrological theory shows that sin β, instead of tan β as used currently, provides a clear theoretical basis for determining the flow-partition proportions in MFD algorithms.
Debris flow risk mitigation by the means of rigid and flexible barriers – experimental tests and impact analysis
Authors: Canelli L. , Ferrero A. M. , Migliazza M. , Segalini A.
Published: May 2012

Abstract. The impact of a debris flow on a structure can have disastrous effects because of the enormous destructive potential of this type of phenomenon. Although the introduction of risk mitigation structures such as the Sabo Dam, the filter dam and more recently flexible barriers is usual, there are very few methods that are universally recognized for the safe design of such structures. This study presents the results of experimental tests, conducted with the use of a specifically created flume, in order to obtain detailed knowledge of the mechanical aspects, and to analyze the dynamics of the impact of a debris flow on different types of structures. The analyses of the tests, together with the calculation of the thrust caused by the flow, have made it possible to analyze the dynamics of the impact, which has shown differing effects, on the basis of the type of barrier that has been installed.
The lithosphere-asthenosphere boundary observed with USArray receiver functions
Authors: Kumar P. , Yuan X. , Kind R. , Mechie J.
Published: May 2012

Abstract. The dense deployment of seismic stations so far in the western half of the United States within the USArray project provides the opportunity to study in greater detail the structure of the lithosphere-asthenosphere system. We use the S receiver function technique for this purpose, which has higher resolution than surface wave tomography, is sensitive to seismic discontinuities, and is free from multiples, unlike P receiver functions. Only two major discontinuities are observed in the entire area down to about 300 km depth. These are the crust-mantle boundary (Moho) and a negative boundary, which we correlate with the lithosphere-asthenosphere boundary (LAB), since a low velocity zone is the classical definition of the seismic observation of the asthenosphere by Gutenberg (1926). Our S receiver function LAB is at a depth of 70–80 km in large parts of westernmost North America. East of the Rocky Mountains, its depth is generally between 90 and 110 km. Regions with LAB depths down to about 140 km occur in a stretch from northern Texas, over the Colorado Plateau to the Columbia basalts. These observations agree well with tomography results in the westernmost USA and on the east coast. However, in the central cratonic part of the USA, the tomography LAB is near 200 km depth. At this depth no discontinuity is seen in the S receiver functions. The negative signal near 100 km depth in the central part of the USA is interpreted by Yuan and Romanowicz (2010) and Lekic and Romanowicz (2011) as a recently discovered mid-lithospheric discontinuity (MLD). A solution for the discrepancy between receiver function imaging and surface wave tomography is not yet obvious and requires more high resolution studies at other cratons before a general solution may be found. Our results agree well with petrophysical models of increased water content in the asthenosphere, which predict a sharp and shallow LAB also in continents (Mierdel et al., 2007).
Translation of Stem Cell Research: Points to Consider in Designing Preclinical Animal Studies
Authors: Frey-Vasconcells Joyce , Whittlesey Kevin J. , Baum Elona , Feigal Ellen G.
Published: May 2012

Stem cell-based therapies hold tremendous promise for the treatment of serious diseases and injuries. Although hematopoietic stem cell transplantation is routinely used as part of the treatment regime for some malignancies and genetic diseases, most stem cell-based therapeutic products are investigational and still require preclinical and clinical studies to support their many novel therapeutic uses. Because of the multiple sources of stem cells, the plethora of potential applications, and the novel mechanism of action of stem cell-based therapies, there is no single set of universal guidance documents that can be used to inform the preclinical development path for these therapeutics. Specific technical issues relating to the transplantation of human cells in animals, new delivery procedures, and laborious methods to characterize transplanted cells can present further challenges in the design and execution of preclinical animal studies for stem cell-based therapeutic products. In this article, we outline important parameters to guide the design of preclinical studies for stem cell-based therapeutics. In addition, we review the types of preclinical studies that should be considered depending on the nature and specific use of the intended stem cell therapeutic product. Finally, we describe important considerations in the design and execution of specific studies to monitor the efficacy, toxicity, biodistribution, and tumorigenicity of stem cell-based therapeutics.
Specimen Collection for Induced Pluripotent Stem Cell Research: Harmonizing the Approach to Informed Consent
Authors: Lowenthal Justin , Lipnick Scott , Rao Mahendra , Hull Sara Chandros
Published: May 2012

Induced pluripotent stem cells (iPSCs) have elicited excitement in both the scientific and ethics communities for their potential to advance basic and translational research. They have been hailed as an alternative to derivation from embryos that provides a virtually unlimited source of pluripotent stem cells for research and therapeutic applications. However, research with iPSCs is ethically complex, uniquely encompassing the concerns associated with genomics, immortalized cell lines, transplantation, human reproduction, and biobanking. Prospective donation of tissue specimens for iPSC research thus requires an approach to informed consent that is constructed for this context. Even in the nascent stages of this field, approaches to informed consent have been variable in ways that threaten the simultaneous goals of protecting donors and safeguarding future research and translation, and investigators are seeking guidance. We address this need by providing concrete recommendations for informed consent that balance the perspectives of a variety of stakeholders. Our work combines analysis of consent form language collected from investigators worldwide with a conceptual balancing of normative ethical concerns, policy precedents, and scientific realities. Our framework asks people to consent prospectively to a broad umbrella of foreseeable research, including future therapeutic applications, with recontact possible in limited circumstances. We argue that the long-term goals of regenerative medicine, interest in sharing iPSC lines, and uncertain landscape of future research all would be served by a framework of ongoing communication with donors. Our approach balances the goals of iPSC and regenerative medicine researchers with the interests of individual research participants.
Shape‐Memory Properties of Polyetherurethane Foams Prepared by Thermally Induced Phase Separation
Authors: Sauter Tilman , Lützow Karola , Schossig Michael , Kosmella Hans , Weigel Thomas , Kratz Karl , Lendlein Andreas
Published: May 2012

In this study, we report the preparation of two structurally different shape‐memory polymer foams by thermally induced phase separation (TIPS) from amorphous polyetherurethanes. Foams with either a homogeneous, monomodal, or with a hierarchically structured, bimodal, pore size distribution are obtained by adoption of the cooling protocol. The shape‐memory properties have been investigated for both foam structures by cyclic, thermomechanical experiments, while the morphological changes on the micro scale (pore level) have been compared to the macro scale by an in situ micro compression device experiment. The results show that the hierarchically structured foam achieves higher shape‐recovery rates and a higher total recovery as compared to the homogeneous foam, which is due to an increased energy storage capability by micro scale bending of the hierarchically structured foam compared to pure compression of the homogeneous foam.
Saethre–Chotzen phenotype with learning disability and hyper IgE phenotype in a patient due to complex chromosomal rearrangement involving chromosomes 3 and 7
Authors: Zechi‐Ceide Roseli Maria , Rodrigues Melina Guerreiro , Jehee Fernanda Sarquis , Kokitsu‐Nakata Nancy Mizue , Passos‐Bueno Maria Rita , Guion‐Almeida Maria Leine
Published: May 2012

The authors describe on a Brazilian girl with coronal synostosis, facial asymmetry, ptosis, brachydactyly, significant learning difficulties, recurrent scalp infections with marked hair loss, and elevated serum immunoglobulin E. Standard lymphocyte karyotype showed a small additional segment in 7p21[46,XX,add(7)(p21)]. Deletion of the TWIST1 gene, detected by Multiplex Ligation Probe‐dependent Amplification (MPLA) and array‐CGH, was consistent with phenotype of Saethre–Chotzen syndrome. Array CGH also showed deletion of four other genes at 7p21.1 (SNX13, PRPS1L1, HD9C9, and FERD3L) and the deletion of six genes (CACNA2D2, C3orf18, HEMK1, CISH, MAPKAPK3, and DOCK3) at 3p21.31. Our case reinforces FERD3L as candidate gene for intellectual disability and suggested that genes located in 3p21.3 can be related to hyper IgE phenotype. © 2012 Wiley Periodicals, Inc.
Power consumption in the compacting process of polymer particulate solids in a vane extruder
Authors: Qu Jin‐Ping , Zhao Xiao‐Qiang , Li Jian‐Bo , Cai Si‐Qi
Published: May 2012

An innovational vane extruder made polymeric materials endure an elongation stress that was much larger than the shearing stress in the extrusion process. The operating principle of the vane extruder was completely different than that of conventional screw extruders. As the first stage of polymer processing in the vane extruder, the process of solids conveying was composed of feeding, compacting, and discharging. Most of the energy was consumed in the compacting process of polymer particulate solids in this stage. A mathematical model was developed to analyze the power consumption in the process. The model showed that the power consumption was mainly influenced by the structural parameters of the vane extruder, including the rotor diameter, eccentricity, and axial width of the vane unit. The analysis indicated that more energy was used to generate pressure in the vane extruder than in a screw extruder. The theoretical model was verified by the experimental results. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Tunable morphology and photoluminescence of poly(styrene‐block‐4‐vinylpyridine)–cadmium sulfide nanocomposites
Authors: Dong Yanmao
Published: May 2012

Poly(styrene‐block‐4‐vinylpyridine) (PS4VP)–CdS nanocomposites containing different concentrations of CdS were synthesized by an in situ method. Scanning electron microscopy and transmission electron microscopy results indicate that the morphologies of PS4VP–Cd(II) and PS4VP–CdS were controlled by the Cd(II) concentration and the solvent, respectively. The effects of the CdS concentration on the crystal style of CdS in PS4VP–CdS and the photoluminescence (PL) properties of the PS4VP–CdS were also examined. By a comparison of the PL spectra of PS4VP–CdS in solutions, films, and powders, the PL mechanism of PS4VP–CdS was also delivered. The PS4VP–CdS nanocomposite shows potential for application in water‐soluble fluorescence probes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Novel PDMS‐based membranes: Sodium chloride and glucose permeability
Authors: Naeimi Mitra , Karkhaneh Akbar , Barzin Jalal , Khorasani Mohammad Taghi , Ghaffarieh Alireza
Published: May 2012

Permeation of sodium chloride and glucose through polydimethylsiloxane‐poly(N‐isopropylacrylamide) (PDMS‐PNIPAAm) interpenetrating polymer networks (IPNs) of two different microstructures was investigated. We have successfully developed small‐molecule permeable IPNs, by modifying PDMS film structure. A group of PDMS films was prepared using conventional solvent casting (SC) method and another group produced by introducing oil, followed by SC and leaching the oil out (SCOL method). Scanning electron microscopy (SEM) and attenuated total reflection fourier transformer infrared (ATR‐FTIR) spectroscopy results confirmed the presence of PNIPAAm in the SC and SCOL IPNs. Results obtained from spectra of differential scanning calorimetry (DSC) showed that these IPNs had a phase transition temperature at about 32°C. Permeation measurements showed that the presence of PNIPAAm as the second phase in the IPN, improved the permeability of PDMS film. According to the results, maximum permeation coefficient was related to SCOL IPN containing 15.8% ± 0.3%PNIPAAm, at 23°C (5.98 × 10−7 ± 7.93 × 10−9 cm2/s for sodium chloride and 3.6 × 10−7 ± 7 × 10−9 cm2/s for glucose). These results suggested that these PDMS‐PNIPAAm IPNs with sodium chloride and glucose permeability may be further developed as ophthalmic biomaterials or corneal replacements. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Mechanical properties of surface‐treated banana fiber/polylactic acid biocomposites: A comparative study of theoretical and experimental values
Authors: Jandas P. J. , Mohanty S. , Nayak S. K.
Published: May 2012

Current study evaluates the effect of fiber surface treatments on the mechanical properties of banana fiber (BF) reinforced polylactic acid (PLA) biocomposites. Experimental results indicate increase in tensile modulus and strength upon surface treatments of BF with various silanes (APS and Si69) and NaOH. Approximately, an increase of 136% in tensile strength and 49% in impact strength was obtained in case of biocomposites with Si69‐treated BF compared with the untreated BF biocomposites. Also, experimentally determined mechanical modulus of untreated and surface‐treated BF biocomposite has been compared with the mechanical modulus calculated using various micromechanical models. Models such as Hirsch's, modified Bawyer and Bader's, and Brodnyan model showed good agreement with the experimentally determined results. Similarly, other models like Halpin‐Tsai, Nielson modified Halpin‐Tsai, and Cox's model also have been tried for the comparative study with the experimental data. Surface modification of BF showed increased interfacial adhesion between the fiber and the matrix which was evident from lowered difference between the experimentally and theoretically derived mechanical modulus. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The ADOS Calibrated Severity Score: Relationship to Phenotypic Variables and Stability over Time
Authors: Shumway Stacy , Farmer Cristan , Thurm Audrey , Joseph Lisa , Black David , Golden Christine
Published: May 2012

Measurement of the severity of autism at a single time point, and over time, is a widespread challenge for researchers. Recently, Gotham, Pickles, and Lord published a severity metric (calibrated severity scores; CSS) that takes into account age and language level and is based on raw total scores of the Autism Diagnostic Observation Schedule (ADOS), a standardized measure commonly used in autism diagnosis. The present study examined psychometric characteristics of the CSS compared to raw scores in an independent sample of 368 children aged 2 to 12 years with autism, pervasive developmental disorder‐not otherwise specified (PDD‐NOS), non‐spectrum delay, or typical development. Reflecting the intended calibration, the CSS were more uniformly distributed within clinical diagnostic category and across ADOS modules than were raw scores. Cross‐sectional analyses examining raw and severity scores and their relationships to participant characteristics revealed that verbal developmental level was a significant predictor of raw score but accounted for significantly less variance in the CSS. Longitudinal analyses indicated overall stability of the CSS over 12 to 24 months in children with autism. Findings from this study support the use of the CSS as a more valid indicator of autism severity than the ADOS raw total score, and extend the literature by examining the stability over 12 to 24 months of the CSS in children with ASD. Autism Res 2012, 5: 267–276. © 2012 International Society for Autism Research, Wiley Periodicals, Inc.
A high‐throughput assay for enzymatic polyester hydrolysis activity by fluorimetric detection
Authors: Wei Ren , Oeser Thorsten , Billig Susan , Zimmermann Wolfgang
Published: May 2012

A fluorimetric assay for the fast determination of the activity of polyester‐hydrolyzing enzymes in a large number of samples has been developed. Terephthalic acid (TPA) is a main product of the enzymatic hydrolysis of polyethylene terephthalate (PET), a synthetic polyester. Terephthalate has been quantified following its conversion to the fluorescent 2‐hydroxyterephthalate by an iron autoxidation‐mediated generation of free hydroxyl radicals. The assay proved to be robust at different buffer concentrations, reaction times, pH values, and in the presence of proteins. A validation of the assay was performed by analyzing TPA formation from PET films and nanoparticles catalyzed by a polyester hydrolase from Thermobifida fusca KW3 in a 96‐well microplate format. The results showed a close correlation (R2 = 0.99) with those obtained by a considerably more tedious and time‐consuming HPLC method, suggesting the aptness of the fluorimetric assay for a high‐throughput screening for polyester hydrolases. The method described in this paper will facilitate the detection and development of biocatalysts for the modification and degradation of synthetic polymers. The fluorimetric assay can be used to quantify the amount of TPA obtained as the final degradation product of the enzymatic hydrolysis of PET. In a microplate format, this assay can be applied for the high‐throughput screening of polyester hydrolases.
Visualizing feasible operating ranges within tissue engineering systems using a “windows of operation” approach: A perfusion‐scaffold bioreactor case study
Authors: McCoy Ryan J. , O'Brien Fergal J.
Published: May 2012

Tissue engineering approaches to developing functional substitutes are often highly complex, multivariate systems where many aspects of the biomaterials, bio‐regulatory factors or cell sources may be controlled in an effort to enhance tissue formation. Furthermore, success is based on multiple performance criteria reflecting both the quantity and quality of the tissue produced. Managing the trade‐offs between different performance criteria is a challenge. A “windows of operation” tool that graphically represents feasible operating spaces to achieve user‐defined levels of performance has previously been described by researchers in the bio‐processing industry. This paper demonstrates the value of “windows of operation” to the tissue engineering field using a perfusion‐scaffold bioreactor system as a case study. In our laboratory, perfusion bioreactor systems are utilized in the context of bone tissue engineering to enhance the osteogenic differentiation of cell‐seeded scaffolds. A key challenge of such perfusion bioreactor systems is to maximize the induction of osteogenesis but minimize cell detachment from the scaffold. Two key operating variables that influence these performance criteria are the mean scaffold pore size and flow‐rate. Using cyclooxygenase‐2 and osteopontin gene expression levels as surrogate indicators of osteogenesis, we employed the “windows of operation” methodology to rapidly identify feasible operating ranges for the mean scaffold pore size and flow‐rate that achieved user‐defined levels of performance for cell detachment and differentiation. Incorporation of such tools into the tissue engineer's armory will hopefully yield a greater understanding of the highly complex systems used and help aid decision making in future translation of products from the bench top to the market place. Biotechnol. Bioeng. 2012; 109: 3161–3171. © 2012 Wiley Periodicals, Inc.
STD NMR Study of the Interactions between Antibody 2G12 and Synthetic Oligomannosides that Mimic Selected Branches of gp120 Glycans
Authors: Enríquez‐Navas Pedro M. , Chiodo Fabrizio , Marradi Marco , Angulo Jesús , Penadés Soledad
Published: May 2012

The human immunodeficiency virus type‐1 (HIV‐1) is able to shield immunogenic peptide epitopes on its envelope spike (a trimer of two glycoproteins, gp120 and gp41) by presenting numerous host‐derived N‐linked glycans. Nevertheless, broadly neutralizing antibodies against gp120 and gp41 have been isolated from HIV‐1‐infected patients and provide protection against viral challenge in animal models. Among these, the monoclonal antibody 2G12 binds to clusters of high‐mannose‐type glycans that are present on the surface of gp120. These types of glycans have thus been envisaged as target structures for the development of synthetic agents capable of eliciting 2G12‐like antibodies. High‐resolution structural studies of 2G12 and chemically defined glycan‐type ligands, including crystallographic data, have been performed to gain an insight into this interaction. Further studies are still required to design a carbohydrate‐based vaccine for HIV. Our previous NMR studies highlighted different recognition modes of two branched synthetic oligosaccharides, a penta‐ and a heptamannoside, by 2G12 in solution. In order to clarify the underlying structural reasons for such different behaviors, we have herein “dissected” the branches into the linear tri‐ and tetra‐ oligomannosides by chemical synthesis and studied their interactions with 2G12 in solution by saturation transfer difference (STD) NMR spectroscopy. The results confirm the distinct preferences of 2G12 for the studied branches and afford explanations for the observed differences. This study provides important structural information for further ligand optimizations. Possible effects of structural modifications on the solvent‐exposed end of the ligands are also discussed.
Direct visualization of CaMKII at postsynaptic densities by electron microscopy tomography
Authors: Fera Andrea , Dosemeci Ayse , Sousa Alioscka A. , Yang Charlotte , Leapman Richard D. , Reese Thomas S.
Published: May 2012

Ca2+/calmodulin‐dependent protein kinase II (CaMKII) is a major component of postsynaptic densities (PSDs) involved in synaptic regulation. It has been previously shown that upon activity CaMKII from the spine reversibly aggregates at the cytoplasmic surfaces of PSDs, where it encounters various targets for phosphorylation. Targets for CaMKII are also present within the PSD, but there has been no reliable method to pinpoint whether, or where, CaMKII is located inside the PSD. Here we show that CaMKII can be mapped molecule‐by‐molecule within isolated PSDs using negative stain electron microscopy tomography. CaMKII molecules found in the core of the PSD may represent a pool distinct from the CaMKII residing at the cytoplasmic surface. J. Comp. Neurol. 520:4218–4225, 2012. © 2012 Wiley Periodicals, Inc.
Intrinsic signal optical imaging evidence for dorsal V3 in the prosimian galago (Otolemur garnettii)
Authors: Fan Reuben H. , Baldwin Mary K.L. , Jermakowicz Walter J. , Casagrande Vivien A. , Kaas Jon H. , Roe Anna W.
Published: May 2012

Currently, we lack consensus regarding the organization along the anterior border of dorsomedial V2 in primates. Previous studies suggest that this region could be either the dorsomedial area, characterized by both an upper and a lower visual field representation, or the dorsal aspect of area V3, which only contains a lower visual field representation. We examined these proposals by using optical imaging of intrinsic signals to investigate this region in the prosimian galago (Otolemur garnettii). Galagos represent the prosimian radiation of surviving primates; cortical areas that bear strong resemblances across members of primates provide a strong argument for their early origin and conserved existence. Based on our mapping of horizontal and vertical meridian representations, visuotopy, and orientation preference, we find a clear lower field representation anterior to dorsal V2 but no evidence of any upper field representation. We also show statistical differences in orientation preference patches between V2 and V3. We additionally supplement our imaging results with electrode array data that reveal differences in the average spatial frequency preference, average temporal frequency preference, and sizes of the receptive fields between V1, V2, and V3. The lack of upper visual field representation along with the differences between the neighboring visual areas clearly distinguish the region anterior to dorsal V2 from earlier visual areas and argue against a DM that lies along the dorsomedial border of V2. We submit that the region of the cortex in question is the dorsal aspect of V3, thus strengthening the possibility that V3 is conserved among primates. J. Comp. Neurol., 2012. © 2012 Wiley Periodicals, Inc.
Neuroanatomical organization of the cholinergic system in the central nervous system of a basal actinopterygian fish, the senegal bichirPolypterus senegalus
Authors: López Jesús M. , Perlado Jorge , Morona Ruth , Northcutt R. Glenn , González Agustín
Published: May 2012

Polypterid bony fishes are believed to be basal to other living ray‐finned fishes, and their brain organization is therefore critical in providing information as to primitive neural characters that existed in the earliest ray‐finned fishes. The cholinergic system has been characterized in more advanced ray‐finned fishes, but not in polypterids. In order to establish which cholinergic neural centers characterized the earliest ray‐finned fishes, the distribution of choline acetyltransferase (ChAT) is described inPolypterusand compared with the distribution of this molecule in other ray‐finned fishes. Cell groups immunoreactive for ChAT were observed in the hypothalamus, the habenula, the optic tectum, the isthmus, the cranial motor nuclei, and the spinal motor column. Cholinergic fibers were observed in both the telencephalic pallium and the subpallium, in the thalamus and pretectum, in the optic tectum and torus semicircularis, in the mesencephalic tegmentum, in the cerebellar crest, in the solitary nucleus, and in the dorsal column nuclei. Comparison of the data within a segmental neuromeric context indicates that the cholinergic system in polypterid fishes is generally similar to that in other ray‐finned fishes, but cholinergic‐positive neurons in the pallium and subpallium, and in the thalamus and cerebellum, of teleosts appear to have evolved following the separation of polypterids and other ray‐finned fishes. J. Comp. Neurol. 521:24–49, 2013. © 2012 Wiley Periodicals, Inc.
Alterations in sulfated chondroitin glycosaminoglycans following controlled cortical impact injury in mice
Authors: Yi Jae‐Hyuk , Katagiri Yasuhiro , Susarla Bala , Figge David , Symes Aviva J. , Geller Herbert M.
Published: May 2012

Chondroitin sulfate proteoglycans (CSPGs) play a pivotal role in many neuronal growth mechanisms including axon guidance and the modulation of repair processes following injury to the spinal cord or brain. Many actions of CSPGs in the central nervous system (CNS) are governed by the specific sulfation pattern on the glycosaminoglycan (GAG) chains attached to CSPG core proteins. To elucidate the role of CSPGs and sulfated GAG chains following traumatic brain injury (TBI), controlled cortical impact injury of mild to moderate severity was performed over the left sensory motor cortex in mice. Using immunoblotting and immunostaining, we found that TBI resulted in an increase in the CSPGs neurocan and NG2 expression in a tight band surrounding the injury core, which overlapped with the presence of 4‐sulfated CS GAGs but not with 6‐sulfated GAGs. This increase was observed as early as 7 days post injury (dpi), and persisted for up to 28 dpi. Labeling with markers against microglia/macrophages, NG2+ cells, fibroblasts, and astrocytes showed that these cells were all localized in the area, suggesting multiple origins of chondroitin‐4‐sulfate increase. TBI also caused a decrease in the expression of aggrecan and phosphacan in the pericontusional cortex with a concomitant reduction in the number of perineuronal nets. In summary, we describe a dual response in CSPGs whereby they may be actively involved in complex repair processes following TBI. J. Comp. Neurol. 520:3295–3313, 2012. © 2012 Wiley Periodicals, Inc.
On lateral septum‐like characteristics of outputs from the accumbal hedonic “hotspot” of Peciña and Berridge with commentary on the transitional nature of basal forebrain “boundaries”
Authors: Zahm Daniel S. , Parsley Kenneth P. , Schwartz Zachary M. , Cheng Anita Y.
Published: May 2012

Peciña and Berridge (2005; J Neurosci 25:11777–11786) observed that an injection of the μ‐opioid receptor agonist DAMGO (D‐ala2‐N‐Me‐Phe4‐Glycol5‐enkephalin) into the rostrodorsal part of the accumbens shell (rdAcbSh) enhances expression of hedonic “liking” responses to the taste of an appetitive sucrose solution. Insofar as the connections of this hedonic “hotspot” were not singled out for special attention in the earlier neuroanatomical literature, we undertook to examine them. We observed that the patterns of inputs and outputs of the rdAcbSh are not qualitatively different from those of the rest of the Acb, except that outputs from the rdAcbSh to the lateral preoptic area and anterior and lateral hypothalamic areas are anomalously robust and overlap extensively with those of the lateral septum. We also detected reciprocal interconnections between the rdAcbSh and lateral septum. Whether and how these connections subserve hedonic impact remains to be learned, but these observations lead us to hypothesize that the rdAcbSh represents a basal forebrain transition area, in the sense that it is invaded by neurons of the lateral septum, or possibly transitional neuronal forms sharing properties of both structures. We note that the proposed transition zone between lateral septum and rdAcbSh would be but one of many in the basal forebrain and conclude by reiterating the longstanding argument that the transitional nature of such boundary areas has functional importance, of which the precise nature will remain elusive until the neurophysiological and neuropharmacological implications of such zones of transition are more generally acknowledged and better addressed. J. Comp. Neurol. 521:50–68, 2013. © 2012 Wiley Periodicals, Inc.
On the relevance of morality in social psychology: An introduction to a virtual special issue
Authors: Pagliaro Stefano
Published: May 2012

Recently, social psychology has become central in the study of morality. This turn to morality as a topic builds on social psychologists' long‐standing interest in issues closely related to morality, such as cooperation, empathy, fairness, social norms and deviance. The present paper introduces a (virtual) special issue on morality by highlighting some of the 41 articles on “moral” or “morality” that have appeared in the European Journal of Social Psychology from 1973 to the present. The nineteen highlighted papers are organized into the main topics covered in research on morality published in EJSP: Emotion, Impression Formation and Trait Inference, Norms and Deviance, Stereotypes, and Reasoning and Judgment. A description of the historical trends that characterized research on morality in EJSP is also provided. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization of odour active compounds in strawberry vinegars
Authors: Ubeda C. , Callejón R. M. , Troncoso A. M. , Moreno‐Rojas J. M. , Peña F. , Morales M. L.
Published: May 2012

Odour‐active compounds in strawberry vinegars were determined by gas chromatography equipped with an olfactometer using the modified frequency (MF) technique. The initial strawberry substrate was also analysed showing that ethyl 2‐methylbutyrate, mesifurane, β‐damascenone, furaneol and γ‐decalactone were preserved during the double fermentation process, presenting high MF values. The final aromatic profile of strawberry vinegars is formed both by compounds from the substrate and by those formed during alcoholic and acetous fermentation. Due to their high MF, a total of 12 odour zones, identified as acetic, butyric and isovaleric acids, methional, 3‐nonen‐2‐one, 2‐phenylethanol, pantolactone + furaneol, p‐vinylguaiacol, sotolon, phenylacetic acid and vanillin, were considered as possible impact odorants of strawberry vinegars. Finally, all potential impact odorants with similar sensory descriptors were grouped into eight categories, these being: fruity, sweet, grassy, spicy, butter–lactic–cheesy, chemical, empyreumatic and miscellaneous. According to the MF percentage of these categories, grassy, fruity, sweet and spicy aroma seem to have the highest influence on the overall impression of strawberry vinegars. Copyright © 2012 John Wiley & Sons, Ltd.