bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence for parallel adaptation to climate across the natural range of Arabidopsis thaliana
Authors: Stearns Frank W. , Fenster Charles B.
Published: June 2013

How organisms adapt to different climate habitats is a key question in evolutionary ecology and biological conservation. Species distributions are often determined by climate suitability. Consequently, the anthropogenic impact on earth's climate is of key concern to conservation efforts because of our relatively poor understanding of the ability of populations to track and evolve to climate change. Here, we investigate the ability of Arabidopsis thaliana to occupy climate space by quantifying the extent to which different climate regimes are accessible to different A. thaliana genotypes using publicly available data from a large‐scale genotyping project and from a worldwide climate database. The genetic distance calculated from 149 single‐nucleotide polymorphisms (SNPs) among 60 lineages of A. thaliana was compared to the corresponding climate distance among collection localities calculated from nine different climatic factors. A. thaliana was found to be highly labile when adapting to novel climate space, suggesting that populations may experience few constraints when adapting to changing climates. Our results also provide evidence of a parallel or convergent evolution on the molecular level supporting recent generalizations regarding the genetics of adaptation.
Lake Malawi cichlid evolution along a benthic/limnetic axis
Authors: Hulsey C. D. , Roberts R. J. , Loh Y.‐H. E. , Rupp M. F. , Streelman J. T.
Published: June 2013

Divergence along a benthic to limnetic habitat axis is ubiquitous in aquatic systems. However, this type of habitat divergence has largely been examined in low diversity, high latitude lake systems. In this study, we examined the importance of benthic and limnetic divergence within the incredibly species‐rich radiation of Lake Malawi cichlid fishes. Using novel phylogenetic reconstructions, we provided a series of hypotheses regarding the evolutionary relationships among 24 benthic and limnetic species that suggests divergence along this axis has occurred multiple times within Lake Malawi cichlids. Because pectoral fin morphology is often associated with divergence along this habitat axis in other fish groups, we investigated divergence in pectoral fin muscles in these benthic and limnetic cichlid species. We showed that the eight pectoral fin muscles and fin area generally tended to evolve in a tightly correlated manner in the Lake Malawi cichlids. Additionally, we found that larger pectoral fin muscles are strongly associated with the independent evolution of the benthic feeding habit across this group of fish. Evolutionary specialization along a benthic/limnetic axis has occurred multiple times within this tropical lake radiation and has produced repeated convergent matching between exploitation of water column habitats and locomotory morphology.
An Iron(II)[1,3‐bis(2′‐pyridylimino)isoindoline] Complex as a Catalyst for Substrate Oxidation with H2O2 – Evidence for a Transient Peroxidodiiron(III) Species
Authors: Pap József S. , Cranswick Matthew A. , Balogh‐Hergovich É. , Baráth Gábor , Giorgi Michel , Rohde Gregory T. , Kaizer József , Speier Gábor , Que Lawrence
Published: June 2013

The complex [Fe(indH)(solvent)3](ClO4)2 (1) has been isolated from the reaction of equimolar amounts of 1,3‐bis(2′‐pyridylimino)isoindoline (indH) and Fe(ClO4)2 in acetonitrile and characterized by X‐ray crystallography and several spectroscopic techniques. It is a suitable catalyst for the oxidation of thioanisoles and benzyl alcohols with H2O2 as the oxidant. Hammett correlations and kinetic isotope effect experiments support the involvement of an electrophilic metal‐based oxidant. A metastable green species (2) is observed when 1 is reacted with H2O2 at –40 °C and has a FeIII(μ‐O)(μ‐O2)FeIII core on the basis of UV/Vis, electron paramagnetic resonance, resonance Raman, and X‐ray absorption spectroscopic data.
Redox Reactions Between Guanidine Electron Donors and Silver Dicyanamide: Synthesis of C,N Material Precursors and Coordination Polymers
Authors: Eberle Benjamin , Herrmann Hendrik , Kaifer Elisabeth , Himmel Hans‐Jörg
Published: June 2013

Reaction of the organic electron donors ttmgb [1,2,4,5‐tetrakis(tetramethylguanidinyl)benzene] and tdmegb [1,2,4,5‐tetrakis(N,N′‐dimethylethyleneguanidinyl)benzene] with two equivalents of silver dicyanamide, Ag(dca), yielded the two salts (ttmgb)(dca)2 (1a) and (tdmegb)(dca)2 (1b). Their relatively high N/C ratios motivated an analysis of their suitability as precursors to C,N materials. The compounds melt at around 200 °C and decompose at 220 (1a) and 245 °C (1b). Reactions of the organic electron donors with an excess of Ag(dca) resulted in coupled redox and coordination reactions, leading finally to coordination polymers with different dimensionalities. The oxidized guanidine units in the polymers are connected through Ag–dca–Ag bridges, leading to stacks of co‐planar C6 rings. The resulting cationic networks are neutralized by dca anions or anionic Ag(dca) chains.
Thionitrosyl‐ and Selenonitrosyliridium Complexes
Authors: Scheibel Markus G. , Klopsch Isabel , Wolf Hilke , Stollberg Peter , Stalke Dietmar , Schneider Sven
Published: June 2013

The activation of elemental sulfur and selenium with electrophilic iridium nitride [Ir(N){N(CHCHPtBu2)2}]+ allowed the synthesis of thionitrosyl‐ and selenonitrosyliridium complexes. The crystallographic and spectroscopic characterization of this rare series of chalcogenonitrosyl complexes [Ir(NE){N(CHCHPtBu2)2}]+ (E = none, O, S, Se) is discussed in the context of bonding models. The experimental results indicate strong Ir–N–E multiple‐bond character, in agreement with the previously proposed N–E donor–acceptor interaction as an appropriate description for the heavier chalcogens.
Concise Total Synthesis of Hydrazidomycin A, a Rare Hydrazide Metabolite of Streptomyces atratus
Authors: Meyer Florian , Ueberschaar Nico , Hertweck Christian
Published: June 2013

Hydrazidomycins A–C and elaiomycins B–C represent a family of unusual, naturally occurring enehydrazides produced by Streptomyces sp. A general synthetic approach to access these densely functionalized hydrazine derivatives is exemplified by the first total synthesis of hydrazidomycin A. The modular synthesis involves a ruthenium‐catalyzed hydroamidation of an alkyne and a hydrazide‐derived phthalimide to yield predominantly the Z‐configured enehydrazide.
Untersuchungen zu zyklisch horizontal belasteten Pfählen bei veränderlicher Lastrichtung
Authors: Rudolph Christina , Grabe Jürgen
Published: June 2013

Pfahlgründungen sind eine weitverbreitete Gründungsvariante für Offshore‐Windenergieanlagen (OWEA) und sind in diesem Anwendungsgebiet erheblichen horizontalen Lasten ausgesetzt. Diese Belastung variiert in ihrer Amplitude, Frequenz sowie Richtung und ist naturgemäß sehr schwierig zu prognostizieren. Bereits existierende Ergebnisse von Modellversuchen berücksichtigen bislang keine Änderung der Lastrichtung und sind daher nur für eindimensionale Belastungen applikabel. Untersuchungen konnten zeigen, dass eine richtungsveränderliche zyklische Belastung zu größeren Verschiebungen führen kann als eine äquivalente eindimensionale zyklische Belastung. In diesem Beitrag wird das Phänomen anhand von Modellvorstellungen erläutert und anhand der Ergebnisse von Modellversuchen quantitativ betrachtet.

On the deformation behavior of laterally loaded piles with cyclic loading from a varying direction. Pile foundations are a common foundation for offshore wind energy converters. In this application area they are subjected to large lateral loading. This loading varies in amplitude, frequency and direction and is difficult to predict. Currently available analytical design methods derived from model tests do not consider a change in loading direction and are therefore applicable for one‐dimensional loading only. Investigations have shown that a change in loading direction results in higher displacements compared to an equivalent one‐dimensional cyclic loading. In this article models are presented to explain the increasing displacements and to be compared against results from physical modeling.
Quaternary channels within the Northeast German Basin and their relevance on double diffusive convective transport processes: Constraints from 3‐D thermohaline numerical simulations
Authors: Kaiser Björn Onno , Cacace Mauro , Scheck‐Wenderoth Magdalena
Published: June 2013

Key Points

Thermohaline convection evolves within the Northeast German Basin

Thermohaline convection is characterized by a helical flow pattern
Intrusive dike complexes, cumulate cores, and the extrusive growth of Hawaiian volcanoes
Authors: Flinders Ashton F. , Ito Garrett , Garcia Michael O. , Sinton John M. , Kauahikaua Jim , Taylor Brian
Published: June 2013

The Hawaiian Islands are the most geologically studied hot‐spot islands in the world yet surprisingly, the only large‐scale compilation of marine and land gravity data is more than 45 years old. Early surveys served as reconnaissance studies only, and detailed analyses of the crustal‐density structure have been limited. Here we present a new chain‐wide gravity compilation that incorporates historical island surveys, recently published work on the islands of Hawai‘i, Kaua‘i, and Ni‘ihau, and >122,000 km of newly compiled marine gravity data. Positive residual gravity anomalies reflect dense intrusive bodies, allowing us to locate current and former volcanic centers, major rift zones, and a previously suggested volcano on Ka‘ena Ridge. By inverting the residual gravity data, we generate a 3‐D view of the dense, intrusive complexes and olivine‐rich cumulate cores within individual volcanoes and rift zones. We find that the Hāna and Ka‘ena ridges are underlain by particularly high‐density intrusive material (>2.85 g/cm3) not observed beneath other Hawaiian rift zones. Contrary to previous estimates, volcanoes along the chain are shown to be composed of a small proportion of intrusive material (<30% by volume), implying that the islands are predominately built extrusively.
Direct auroral precipitation from the magnetotail during substorms
Authors: Ashour‐Abdalla Maha , Schriver David , Alaoui Mostafa El , Richard Robert , Walker Raymond , Goldstein Melvyn L. , Donovan Eric , Zhou Meng
Published: June 2013

In this study, we examine the causes of electron precipitation during a substorm on 15 February 2008 that lead to auroral brightening. We use global kinetic simulations along with spacecraft and ground‐based data. We find ~keV electrons in the region modeled in the simulation precipitate into the premidnight sector at latitudes between 71° and 75° due to two distinct physical processes: (1) higher latitude precipitation due to electrons that undergo relatively rapid non‐adiabatic pitch angle scattering into the loss cone just earthward of a reconnection region, and (2) lower latitude precipitation due to electrons that are more gradually accelerated primarily parallel to the geomagnetic field by Fermi acceleration. These latter electrons enter the loss cone much closer to Earth at ~−15 to −10 RE. The electron precipitation due to the combination of these two mechanisms coincides spatially with observed auroral brightening during the disturbed event.
Nutrient variability in Subantarctic Mode Waters forced by the Southern Annular Mode and ENSO
Authors: Ayers Jennifer M. , Strutton Peter G.
Published: June 2013

As the primary source of nutrients to the global thermocline, Subantarctic Mode Waters (SAMWs) play a key role in primary production and climate. Here we use repeat hydrographic World Ocean Circulation Experiment/Climate Variability and Predictability data to quantify interannual SAMW nutrient variability and its forcing. Pacific sector SAMW nutrients were significantly correlated with the Southern Annular Mode (SAM) and wind stress curl anomalies associated with a faster meridional overturning circulation (MOC). A stronger MOC results in greater upwelling of nutrients at high latitudes, increased Ekman transport of nutrients equatorward, and subduction of higher preformed nutrient loads in SAMWs. Australian sector SAMWs were significantly correlated with El Niño–Southern Oscillation (ENSO), likely due to its modulation of transport in the East Australian Current extension. Interannual variability in SAMW nutrients impacts downstream tropical export production by as much as 5–12% of the annual mean.
The economic impact of H1N1 on Mexico's tourist and pork sectors
Authors: Rassy Dunia , Smith Richard D.
Published: June 2013

By examining tourist arrivals and pork output and trade statistics, this analysis estimates the economic impact to the Mexican tourism and pork sectors because of the H1N1 influenza pandemic. It also assesses the role of the international response in the context of this economic impact.

For tourism, losing almost a million overseas visitors translated into losses of around $US2.8bn, which extended over a five‐month period, mostly because of the slow return of European travellers. For the pork industry, temporal decreases in output were observed in most of the country and related to H1N1 incidence (p = 0.048, r = 0.37). By the end of 2009, Mexico had a pork trade deficit of $US27m. The losses derived from this pandemic were clearly influenced by the risk perception created in tourist‐supplying and pork trade partners.

Results suggest that the wider economic implications of health‐related emergencies can be significant and need to be considered in preparedness planning. For instance, more effective surveillance and data gathering would enable policy to target emergency funding to the sectors and regions hardest hit. These results also stress the importance of being familiar with trade networks so as to be able to anticipate the international response and respond accordingly. Copyright © 2012 John Wiley & Sons, Ltd.
Performance of chronic kidney disease epidemiology collaboration creatinine-cystatin C equation for estimating kidney function in cirrhosis
Authors: Mindikoglu Ayse L. , Dowling Thomas C. , Weir Matthew R. , Seliger Stephen L. , Christenson Robert H. , Magder Laurence S.
Published: June 2013

Conventional creatinine-based glomerular filtration rate (GFR) equations are insufficiently accurate for estimating GFR in cirrhosis. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) recently proposed an equation to estimate GFR in subjects without cirrhosis using both serum creatinine and cystatin C levels. Performance of the new CKD-EPI creatinine-cystatin C equation (2012) was superior to previous creatinine- or cystatin C-based GFR equations. To evaluate the performance of the CKD-EPI creatinine-cystatin C equation in subjects with cirrhosis, we compared it to GFR measured by nonradiolabeled iothalamate plasma clearance (mGFR) in 72 subjects with cirrhosis. We compared the “bias,” “precision,” and “accuracy” of the new CKD-EPI creatinine-cystatin C equation to that of 24-hour urinary creatinine clearance (CrCl), Cockcroft-Gault (CG), and previously reported creatinine- and/or cystatin C-based GFR-estimating equations. Accuracy of CKD-EPI creatinine-cystatin C equation as quantified by root mean squared error of difference scores (differences between mGFR and estimated GFR [eGFR] or between mGFR and CrCl, or between mGFR and CG equation for each subject) (RMSE = 23.56) was significantly better than that of CrCl (37.69, P = 0.001), CG (RMSE = 36.12, P = 0.002), and GFR-estimating equations based on cystatin C only. Its accuracy as quantified by percentage of eGFRs that differed by greater than 30% with respect to mGFR was significantly better compared to CrCl (P = 0.024), CG (P = 0.0001), 4-variable MDRD (P = 0.027), and CKD-EPI creatinine 2009 (P = 0.012) equations. However, for 23.61% of the subjects, GFR estimated by CKD-EPI creatinine-cystatin C equation differed from the mGFR by more than 30%. Conclusion: The diagnostic performance of CKD-EPI creatinine-cystatin C equation (2012) in patients with cirrhosis was superior to conventional equations in clinical practice for estimating GFR. However, its diagnostic performance was substantially worse than reported in subjects without cirrhosis. (HEPATOLOGY 2014;59:1532-1542)
Psychological Help‐Seeking Intention Among College Students Across Three Problem Areas
Authors: Hess Timothy R. , Tracey Terence J. G.
Published: June 2013

The theory of planned behavior (TPB) was used to understand psychological help‐seeking intention for 3 common concerns: anxiety or depression, career choice concerns, and alcohol or drug use. Eight hundred eighty‐nine university students completed surveys for the TPB variables plus belief in personal efficacy and control to solve the problems. Path analysis demonstrated path invariance, indicating that the importance of TPB variables do not vary based on concern in the decision‐making process.
Writing for Publication: A Guide for Counseling Practice Articles
Authors: Falco Lia D. , McCarthy Christopher J.
Published: June 2013

Practice articles are critical to scholarship in the counseling field. This article provides readers with practical guidelines for the content and organization of practice articles, with the broad objective of developing a framework for presenting such contributions that may be consistently utilized within the counseling literature. A consistent format could be useful in making sure that manuscripts devoted to practice have a structure that is accessible to authors, reviewers, and readers.
Mechanical properties of methacrylate‐based model dentin adhesives: Effect of loading rate and moisture exposure
Authors: Singh Viraj , Misra Anil , Parthasarathy Ranganathan , Ye Qiang , Park Jonggu , Spencer Paulette
Published: June 2013

The aim of this study is to investigate the mechanical behavior of model methacrylate‐based dentin adhesives under conditions that simulate the wet oral environment. A series of monotonic and creep experiments were performed on rectangular beam samples of dentin adhesive in three‐point bending configuration under different moisture conditions. The monotonic test results show a significant effect of loading rate on the failure strength and the linear limit (yield point) of the stress‐strain response. In addition, these tests show that the failure strength is low, and the failure occurs at a smaller deformation when the test is performed under continuously changing moisture conditions. The creep test results show that under constant moisture conditions, the model dentin adhesives can have a viscoelastic response under certain low loading levels. However, when the moisture conditions vary under the same low loading levels, the dentin adhesives have an anomalous creep response accompanied by large secondary creep and high strain accumulation. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1437–1443, 2013.
Wear of novel ceramic‐on‐ceramic bearings under adverse and clinically relevant hip simulator conditions
Authors: Al‐Hajjar Mazen , Jennings Louise M. , Begand Sabine , Oberbach Thomas , Delfosse Daniel , Fisher John
Published: June 2013

Further development of ceramic materials for total hip replacement aim to increase fracture toughness and further reduce the incidence of bearing fracture. Edge loading due to translational mal positioning (microseparation) has replicated stripe wear, wear rates, and bimodal wear debris observed on retrievals. This method has replicated the fracture of early zirconia ceramic‐on‐ceramic bearings. This has shown the necessity of introducing microseparation conditions to the gait cycle when assessing the tribological performance of new hip replacement bearings. Two novel ceramic matrix composite materials, zirconia‐toughened alumina (ZTA) and alumina‐toughened zirconia (ATZ), were developed by Mathys Orthopädie GmbH. In this study, ATZ‐on‐ATZ and ZTA‐on‐ZTA bearing combinations were tested and compared with alumina‐on‐alumina (Al2O3‐on‐Al2O3) bearings under adverse microseparation and edge loading conditions using the Leeds II physiological anatomical hip joint simulator. The wear rate (±95% confidence limit) of ZTA‐on‐ZTA was 0.14 ± 0.10 mm3/million cycles and that of ATZ‐on‐ATZ was 0.06 ± 0.004 mm3/million cycles compared with a wear rate of 0.74 ± 1.73 mm3/million cycles for Al2O3‐on‐Al2O3 bearings. Stripe wear was evident on all bearing combinations; however, the stripe formed on the ATZ and ZTA femoral heads was thinner and shallower that that formed on the Al2O3 heads. Posttest phase composition measurements for both ATZ and ZTA materials showed no significant change in the monoclinic zirconia content. ATZ‐on‐ATZ and ZTA‐on‐ZTA showed superior wear resistance properties when compared with Al2O3‐on‐Al2O3 under adverse edge loading conditions. © 2013 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc., 101B: 1456–1462, 2013.
Bioactive plasma electrolytic oxidation coatings—The role of the composition, microstructure, and electrochemical stability
Authors: Mohedano M. , Guzman R. , Arrabal R. , López Lacomba J.‐L. , Matykina E.
Published: June 2013

A Plasma electrolytic oxidation (PEO) process was used to produce bioactive coatings on Ti. PEO coatings with Ca/P atomic ratio of 1.7 and 4.0 were fabricated and characterized with respect to their morphology, composition, and microstructure. AC and DC electrochemical tests were used to evaluate the effect of (i) organic additives (amino acids, proteins, vitamins, and antibiotics) in alpha‐minimum essential medium (α‐MEM) on electrochemical stability of noncoated and PEO‐coated Ti and (ii) coating composition, microstructure, and corrosion behavior on the cell response in α‐MEM. PEO‐coated Ti showed higher corrosion resistance than the noncoated Ti in MEM with and without organic additives by an order of magnitude. The corrosion resistance in α‐MEM decreased with time for nonmodified Ti and increased for PEO‐coated Ti; the latter was because of the adsorption of the proteins in the coating pores which increased the diffusion resistance. The presence of Ca and P in titanium oxide coating at the Ca/P ratio exceeding that of any stoichiometric Ca–P–O and Ca–P–O–H compounds facilitates faster osteoblast cell adhesion. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1524–1537, 2013.
Synthesis of P(3HB‐co‐4HB) copolymer with target‐specific 4HB molar fractions using combinations of carbon substrates
Authors: Md. Iqbal Nurhezreen , Amirul A.A.
Published: June 2013

BACKGROUND

The incorporation of 4HB units into P(3HB) improves the material application potential as the copolymer exhibits a wide range of physical properties ranging from crystalline plastic to elastic rubber depending on the copolymer composition. Thus, the prospects of synthesizing P(3HB‐co‐4HB) copolymer with various compositions of 4HB would increase its effectiveness as biomaterial.

RESULTS

The residual cell dry weight (RCDW) and PHA concentration obtained under optimized conditions, namely C/N ratio 30, K2HPO4 6.1 g L‐1, incubation period 66 h, temperature 32°C and volume‐to‐flask ratio 47/250 mL increased from 2.9 g L‐1 to 4.9 g L‐1 and 4.2 g L‐1 to 7.6 g L‐1, respectively. P(3HB‐co‐4HB) with varied Mn between 26 kDa and 270 kDa were successfully synthesized using combinations of oleic acid, 1,6‐hexanediol and/or 1,4‐butanediol. The tensile strength and Young's modulus of the copolymers varied from 2 MPa to 24 MPa and 13 MPa to 192 MPa, respectively. Tm and Tg decreased with increasing 4HB molar fractions from 170°C to 68°C and 2.5°C to −31°C, respectively.

CONCLUSION

Oleic acid and (NH4)2SO4 was the best carbon and nitrogen source for PHA biosynthesis. P(3HB‐co‐4HB) copolymer with targeted 4HB molar fractions ranged from 0–65 mol% were synthesized using combinations of two or more carbon substrates by Cupriavidus sp. USMAA2‐4 (DSM 19379) using mixture design. © 2013 Society of Chemical Industry
Solvothermal conversion of magadiite into zeolite omega in a glycerol–water system
Authors: Cui Miao , Wang Yu , Liu Xiaoyu , Zhu Jiang , Sun Jiangbo , Lv Nan , Meng Changgong
Published: June 2013

BACKGROUND

Zeolite omega is used as a catalyst in various fields. Expensive tetramethylammonium cations are the conventional structure‐directing agents for the synthesis of zeolite omega. In this work, glycerol was used as both solvent and structure‐directing agent instead of expensive quaternary ammonium compounds. Zeolite omega has been obtained through conversion of magadiite in this glycerol–water system. The effects of various parameters such as reaction time, temperature, alkalinity and glycerol content were discussed.

RESULTS

Pure zeolite omega could be obtained at 120°C for 10 days with the reactants molar composition of 14 SiO2: Al2O3: 10 Na2O: 169 H2O: 200 glycerol. Water content plays an important role in the solvothermal conversion of magadiite to zeolite omega.

CONCLUSION

The zeolite omega obtained from this system is a rather pure phase free from impurities. A preferential location of the Al atoms in the six‐membered rings of the gmelinites in zeolite omega was observed. A method including extraction and calcination was introduced to remove organic species by which highly ordered pore structure of zeolite was well retained. The present work develops a novel synthesis method for zeolite omega. © 2013 Society of Chemical Industry
Generalized linear modeling of the El Niño/Southern Oscillation with application to seasonal forecasting and climate change projections
Authors: Stevenson S. , Rajagopalan B. , Fox‐Kemper B.
Published: June 2013

A new framework for simulating the El Niño/Southern Oscillation (ENSO) using a generalized linear model (GLM) is provided. The GLM provides a versatile and computationally inexpensive method for investigating ENSO dynamics, by conditioning an ENSO index on an arbitrary set of input variables. Here the system state (El Niño/neutral/La Niña) at previous times is combined with the first few principal components of sea surface temperature (SST) and thermocline depth. Despite having relatively few degrees of freedom, the model accurately reproduces 20th century SST time series, seasonal variance, power spectra, and autocorrelation functions for both the eastern and western Pacific. The GLM also has good overall forecast skill, especially at subyearly lead times; performance is competitive with models currently used for operational ENSO forecasting. The model is then used to examine changes to El Niño/La Niña statistics under CO2 increases, by using the GLM to represent simulations run with the National Center for Atmospheric Research (NCAR) Community Climate System Model (CCSM), versions 3.5 and 4. GLM simulations of 21st century CCSM4 changes to El Niño/La Niña magnitudes show insignificant results, despite a slight increase in El Niño persistence. GLM fits conditioned on millennial stabilized CCSM3.5 simulations with varying CO2 levels, however, show a weakening and shortening of El Niño events as CO2 concentration increases, whereas La Niña events become markedly stronger and do not change significantly in length. The reduction in El Niño persistence in CCSM3.5 is consistent with previous results showing that at higher CO2 levels, a stronger seasonal cycle creates a Southern Hemisphere “seasonal footprint” leading to more efficient El Niño termination.
Detection of linear trends in multisensor time series in the presence of autocorrelated noise: Application to the chlorophyll‐a SeaWiFS and MERIS data sets and extrapolation to the incoming Sentinel 3‐OLCI mission
Authors: Saulquin Bertrand , Fablet Ronan , Mangin Antoine , Mercier Grégoire , Antoine David , Fanton d'Andon Odile
Published: June 2013

The detection of long‐term trends in geophysical time series is a key issue in climate change studies. This detection is affected by many factors: the size of the trend to be detected, the length of the available data sets, and the noise properties. Although the noise autocorrelation observed in geophysical time series does not bias the trend estimate, it affects the estimation of its uncertainty and consequently the ability to detect, or not, a significant trend. Ignoring the noise autocorrelation level typically leads to an overdetection of significant trends. Due to satellite lifetime, usually between 5 and 10 years, sea surface time series do not cover the same period and are acquired by different sensors with different characteristics. These differences lead to unknown level shifts (biases) between the data sets, which affect the trend detection. In this work, we develop a generic framework to detect and evaluate linear trends and level shifts in multisensor time series of satellite chlorophyll‐a concentrations, as provided by the Medium Resolution Imaging Spectrometer instrument (MERIS) and sea‐viewing wide field‐of‐view sensor (SeaWiFS) ocean‐color missions. We also discuss the optimization of the observation networks, in terms of needed time overlap between successive time series to reduce the uncertainty on the detection of long‐term trends. For the incoming Sentinel 3‐Ocean and Land Color Instrument (3‐OLCI) mission that should be launched at the end of 2014, we propose a global map of the number of months of observations to enhance the trend detection performed with the joint SeaWiFS‐MERIS analysis.
Effects of bark beetle‐caused tree mortality on biogeochemical and biogeophysical MODIS products
Authors: Bright Benjamin C. , Hicke Jeffrey A. , Meddens Arjan J. H.
Published: June 2013

Disturbances affect forest‐atmosphere exchanges of carbon, water, and energy, thereby influencing weather and climate. Bark beetle outbreaks are one such disturbance type that alters biogeochemical and biogeophysical processes in forests. Few studies have documented bark beetle impacts to leaf area index (LAI), gross primary productivity (GPP), evapotranspiration (ET), land surface temperature (LST), and surface albedo with satellite observations. Our objective was to use Landsat‐derived estimates of bark beetle‐caused tree mortality and Moderate Resolution Imaging Spectroradiometer (MODIS) land surface products to estimate beetle‐caused changes in LAI, GPP, ET, LST, and surface albedo in northern Colorado. Following bark beetle‐caused tree mortality, decreases occurred in LAI (0.02–0.80 m2m−2, 1–40%), annual GPP (50–248 gC m−2 yr−1, (5–26%), and daily summer ET (0.20–0.70 mm day−1, 13–44%), whereas increases occurred in August LST (1–3.9 K) and February albedo (0.03–0.09, 19–52%). We found greater responses of these variables in areas of greater mortality severity. The extent and severity of tree mortality in northern Colorado caused substantial changes in land surface variables (9–23%) when averaged across all forested areas of our study area. Our results demonstrate that land surface variables are sensitive to bark beetle‐caused tree mortality and that bark beetle outbreaks can significantly impact biogeochemical and biogeophysical processes.
Taking the bite out of culture: The impact of task structure and task type on overcoming impediments to cross‐cultural team performance
Authors: Nouri Rikki , Erez Miriam , Rockstuhl Thomas , Ang Soon , Leshem‐Calif Lee , Rafaeli Anat
Published: June 2013

Research on the effect of cultural diversity on team performance remains inconclusive. We propose to resolve the competing predictions of the information/decision making versus the social categorization theories by integrating two task‐related theories, the situational strength theory and the circumplex model of group tasks. We propose that high task specificity enables similar interpretations and shared understanding among team members, which is needed for effective “execute” (convergent) tasks, is characterized by team cooperation and interdependence. Low task specificity, in contrast, is beneficial for “generate” (creative) tasks, because it does not place constraints on generating original ideas and does not require tight coordination among the team members. We tested the effects of situational strength and task type on the relationship between cultural diversity and team performance in two experiments with 86 and 96 dyads in the first and second experiments, respectively. In both experiments, heterogeneous (Israeli–Singaporean) and homogeneous dyads (Israeli–Israeli and Singaporean–Singaporean) worked under low or high task specificity. In Study 1, dyads performed convergent execution tasks, and in Study 2, they performed creative idea‐generation tasks. The impediment of multiculturalism was reduced in execute (convergent) tasks under high task specificity and in generate (divergent) tasks under low task specificity. Copyright © 2013 John Wiley & Sons, Ltd.
In vivo loading model to examine bone adaptation in humans: A pilot study
Authors: Troy Karen L. , Edwards William Brent , Bhatia Varun A. , Bareither Mary Lou
Published: June 2013

Bone is typically well suited for its habitual loading environment because of its ability to adapt. Although characteristics of the mechanical loading environment predict the bone adaptive response in animals, this has not been prospectively validated in humans. Here, we describe an in vivo loading model in which women apply forces to the radius by leaning onto their hand. We characterized the strain environment imposed on the radius using cadaveric experimentation and conducted a prospective study in which 19 adult women loaded their distal radii 50 cycles/day, 3 days/week, for 28 weeks and seven additional adult women served as controls. In four cadaveric specimens, loading caused compressive principal strains of −1,695 ± 396 μϵ with radial bending dorsally and towards the ulna. Prospective in vivo loading produced measurable improvements to bone and appeared to protect against bone loss associated with seasonal fluctuations in physical activity and sun exposure. Experimental subjects had significant gains to bone volume (BV) and moments of inertia, while, control subjects had significant losses in BMC and moments of inertia. The loading model is thus suitable as a model system for exploring bone adaptation in humans, and may eventually be clinically useful for strengthening the radius of women. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1406–1413, 2013.
From phenolics to phenolipids: Optimizing antioxidants in lipid dispersions
Authors: Figueroa‐Espinoza Maria Cruz , Laguerre Mickaël , Villeneuve Pierre , Lecomte Jérôme
Published: June 2013

Natural non‐polymeric phenolics are known to be powerful antioxidants, but their use for preventing lipid oxidation in unsaturated fat‐based products, such as foodstuffs and cosmetics, is limited owing to their hydrophilic character. A promising technique – referred to as lipophilization – consists of covalently grafting a lipid moiety to the phenolic part to improve both surface activity and oil solubility of a given phenolic antioxidant. After being based on empiricism for decades, the lipophilization of phenolics is today more rationalized, as recent advances in the field have shown that the grafting of a medium chain‐length is the best strategy to design powerful, custom‐made phenolic antioxidants to protect lipid dispersion against oxidation. To illustrate, we report here the main strategies in the lipophilization of phenolic acids, the effect of such modification on the antioxidant properties, and current and potential applications of the resulting phenolipids.
Pinolenic acid as a new source of phyto‐polyunsaturated fatty acid
Authors: No Da Som , Kim In‐Hwan
Published: June 2013

Pinolenic acid (PLA, all‐cis‐5,9,12‐18:3) is an interesting plant‐based polyunsaturated fatty acid of which little is known. The major source of PLA is pine nut oil. PLA has distinctive health benefits such as LDL/VLDL cholesterol lowering potential and displays an appetite suppressing effect. Enrichment of PLA can be carried out by physical procedures or by enzymatic reactions with lipases such as Candida antartica lipase B and Candida rugosa lipase.
The Solvent in Physical Gelation: Polymers Versus Organogelators
Authors: Dasgupta Debarshi , Guenet Jean‐Michel
Published: June 2013

The mechanisms responsible for the physical gelation of polymers and of organogelators are discussed and compared. For polymers, the prerequisite for obtaining fibrillar thermoreversible gels is the impediment of chain folding. This occurs when polymers take on a worm‐like chain conformation with a large persistence length. This property can be intrinsic to the polymer, such as agarose, or can be obtained by the occurrence of polymer–solvent molecular compounds, as is the case for stereoregular polymers. For organogels, it is suggested that the mechanism for producing fibrils involves the much faster growth of one face of the organogel crystal structure with respect to the other two, which can be enhanced via specific interactions with the solvent, something reminiscent of molecular compounds.

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The +3187A/G HLA‐G polymorphic site is associated with polar forms and reactive reaction in leprosy
Authors: Lucena‐Silva N. , Teixeira M. A. G. , Ramos A. de L. , de Albuquerque R. S. , Diniz G. T. N. , Mendes‐Junior C. T. , Castelli E. C. , Donadi E. A.
Published: June 2013

Considering that variability in immune response genes has been associated with susceptibility to leprosy and with disease severity, leprosy presents clinicopathological variants that are highly associated with the immune response, HLA‐G has a well‐recognized role in the modulation of the immune response, and polymorphisms at the 3′ untranslated region (UTR) of the HLA‐G gene may influence HLA‐G production, we studied the polymorphic sites at the 3′ UTR of the HLA‐G gene in leprosy and their association with disease severity. We evaluated by sequencing analysis the allele, genotype, and haplotype frequencies of the 3′ UTR HLA‐G polymorphic sites (14‐bpINDEL/+3003C‐T/+3010C‐G/+3027A‐C/+3035C‐T/+3142C‐G/+3187A‐G/+3196C‐G) in 146 individuals presenting reactive leprosy from a highly endemic area, and associated with bacillary load and the type of reactive leprosy. A total of 128 healthy subjects were also studied. Allele, genotype, and haplotype frequencies for the 3′ UTR HLA‐G polymorphisms in leprosy patients did not differ from those observed in healthy donors. The +3187A allele was responsible for protection against the development of multibacillary leprosy in a dominant model (AA + AG)/GG, OR = 0.11, P = 0.018), and the +3187A allele and +3187A‐A genotype were overrepresented in type II reactive leprosy reaction. The effect of genetic factors on leprosy susceptibility may be hidden by environmental components in highly endemic areas. The HLA‐G + 3187A polymorphic site, which is related to unstable mRNA production, was associated with the development of polar forms of leprosy and reactive leprosy reaction.
Asymptotic dynamics of a deterministic and stochastic predator–prey model with disease in the prey species
Authors: Foryś Urszula , Qiao Meihong , Liu Anping
Published: June 2013

In this paper, we discuss a predator–prey model with the Beddington–DeAngelis functional response of predators and a disease in the prey species. At first we study permanence and global stability of a positive equilibrium for the deterministic version of the model. Then we include a stochastic perturbation of the white noise type. We analyse the influence of this stochastic perturbation on the systems and prove that the positive equilibrium is also globally asymptotically stable in this case. The key point of our analysis is to choose appropriate Lyapunov functionals. We point out the differences between the deterministic and stochastic versions of the model. Copyright © 2013 John Wiley & Sons, Ltd.
Mathematical modeling for multisite phosphorylation with scaffold binding in cell signaling
Authors: Basu Kanadpriya , Liu Xinfeng
Published: June 2013

The mating decision in budding yeast is a switch‐like or bistability response that allows cells to filter out weak pheromone signals or avoid improper mating when a mate is sufficiently close. However, the molecular mechanisms that control the bistability decision are not yet fully understood. In many cases, scaffold proteins are thought to play a key role during this process. A workable definition of a scaffold is a protein that dynamically binds to two or more consecutively acting components of a signaling cascade, such as protein kinase and that kinase's substrate. Here, we show that bistability mechanism can arise from multisite phosphorylation system with scaffold binding when phosphorylation and dephosphorylation occur at different locations. This scaffold binding in a multisite phosphorylation system can robustly result in multiple steady states. By developing generic mathematical models, we argue that the scaffold protein plays an important role in creating bistability, and by treating parameters symbolically, we also thereby reduce the complexity of calculating steady states from simulating differential equations to finding the roots of polynomials, of which the degree depends on the number of phosphorylation sites N. Copyright © 2013 John Wiley & Sons, Ltd.
Repulsive guidance molecules (RGMs) and neogenin in bone morphogenetic protein (BMP) signaling
Authors: Tian Chenxi , Liu Jun
Published: June 2013

Bone morphogenetic proteins (BMPs) belong to the transforming growth factor‐beta (TGFβ) superfamily. BMPs mediate a highly conserved signal transduction cascade through the type‐I and type‐II serine/threonine kinase receptors and intracellular Smad proteins, which regulate multiple developmental and homeostatic processes. Mutations in this pathway can cause various diseases in humans, such as skeletal disorders, cardiovascular diseases, and various cancers. Multiple levels of regulation, including extracellular regulation, help to ensure proper spatiotemporal control of BMP signaling in the right cellular context. The family of repulsive guidance molecules (RGMs) and the type‐I transmembrane protein neogenin, a paralog of DCC (Deleted in Colorectal Cancer), have been implicated in modulating the BMP pathway. In this review, we discuss the properties and functions of RGM proteins and neogenin, focusing on their roles in the modulation of BMP signal transduction. Mol. Reprod. Dev. 80: 700–717, 2013. © 2013 Wiley Periodicals, Inc.
Vascular pattern in monochorionic placentas with spontaneous TAPS and TTTS with residual anastomoses after laser: a case–control study
Authors: Favre Romain , Koch Antoine , Weingertner Aenn‐Sophie , Sananes Nicolas , Trieu Ngoc Tu , Kohler Monique , Guerra Fernando , Nisand Israel
Published: June 2013

Objective

This study aimed to compare the angio‐architecture of monochorionic placentas of spontaneous twin anaemia–polycythemia sequence (TAPS) with placenta of twin‐to‐twin transfusion syndrome (TTTS) with residual anastomoses after laser coagulation and placentas of uncomplicated monochorionic twin pregnancies.

Methods

This case–control study compares the angio‐architecture of monochorionic placentas of spontaneous TAPS (n = 12) with that of monochorionic placentas of TTTS treated by laser coagulation with residual anastomoses (TTTS + RA; n = 20) and placentas of monochorionic pregnancies without complications (n = 24), matched for gestational age. Placental sharing and angio‐architecture were assessed by injection of colored dye.

Results

The median diameter of the arterio‐venous (AV) anastomoses in TAPS placentas was 2.26, 0.215 with TTTS + RA and 4.17 mm in normal monochorionic pregnancies (p < .03). The mean diameter of the arterio‐arterial (AA) anastomoses in monochorionic placentas with spontaneous TAPS was 0.2 mm versus 0.15 mm in TTTS + RA and 2.0 mm in normal pregnancies, respectively (p < 0.03, p < 0.007). The number of AA anastomoses was lower with TAPS (0.3 versus 0.50 and 1, respectively, p < 0.015, p < 0.0001). Besides, unequal sharing was more frequent in TAPS as compared with monochorionic normal pregnancies (75% versus 29%, p = 0.03).

Conclusion

Age matched placentas of spontaneous TAPS are characterized by very small AV anastomoses and very few AA anastomoses of smaller diameter than placentas of monochorionic twins with TTTS or without obvious complications. © 2013 John Wiley & Sons, Ltd.
Development of a female attractant for the click beetle pest Agriotes brevis
Authors: Vuts József , Furlan Lorenzo , Csonka Éva Bálintné , Woodcock Christine M , Caulfield John C , Mayon Patrick , Pickett John A , Birkett Michael A , Tóth Miklós
Published: June 2013

BACKGROUND

Traps suitable for catching female Agriotes click beetles may provide better reconnaissance than pheromone‐baited traps which catch only males, thereby contributing to more efficient crop protection. The basis for this study came from (i) observations of female Agriotes brevis (Candeze) aggregating beneath foliage of Medicago sativa (L.) and Lolium italicum (A. Br.) placed on plastic sheets on bare soil, and (ii) field tests demonstrating attraction of females to traps baited with foliage from these plants. The aim was to identify and field test volatile compounds from M. sativa and L. italicum leaves.

RESULTS

A number of electrophysiologically active chemicals were identified from headspace extracts of M. sativa and L. italicum. Three different synthetic blends of the identified compounds, comprising four, seven and nine components, were field tested. The four‐ and nine‐component blends caught more female A. brevis than unbaited traps, with the proportion of females not differing between blends.

CONCLUSION

The plant‐derived blends were shown to catch female A. brevis under field conditions when applied in traps. Of these, the four‐component blend, given its relatively simple composition [(Z)‐3‐hexenyl acetate:methyl benzoate:(Z)‐3‐hexen‐1‐ol:methyl salicylate 300:5:30:30 mg bait−1], may be a suitable ‘standard’ blend for bait optimisation. © 2013 Society of Chemical Industry
Anti‐allergic Effect of Pleuran (β‐glucan from Pleurotus ostreatus) in Children with Recurrent Respiratory Tract Infections
Authors: Jesenak Milos , Hrubisko Martin , Majtan Juraj , Rennerova Zuzana , Banovcin Peter
Published: June 2013

Recurrent respiratory tract infections (RRTIs) present a very important problem in paediatric praxis. As true immunodeficiencies are rare, one of the most important factors assumed to contribute to increased respiratory morbidity is atopy. Several preparations of natural origin have been used for the prevention of RRTIs, and some of the most effective immunomodulators are biologically active polysaccharides – e.g. ß‐glucans. In our randomised, double‐blind, placebo‐controlled study, we investigated the prevalence of atopy in a group of children with RRTIs and the potential anti‐allergic effect of pleuran (ß‐glucan isolated from Pleurotus ostreatus) on basic laboratory markers of allergic inflammation. We confirmed that atopy may be an important factor contributing to the increased respiratory morbidity in children with RRTIs. The active treatment with pleuran resulted in a significant reduction of peripheral blood eosinophilia and stabilised the levels of total IgE in serum. This was more evident in atopic subjects. Pleuran showed a potential anti‐allergic effect. This previously non‐described effect could expand the application of this natural immunomodulator also as a complementary adjuvant therapy in allergic patients. Copyright © 2013 John Wiley & Sons, Ltd.