bluuebunny/crossref_metadata_2025 huggingface dataset:
Halido‐Bridged 1D Mixed‐Valence CuI–CuII Coordination Polymers Bearing a Piperidine‐1‐carbodithioato Ligand: Crystal Structure, Magnetic and Conductive Properties, and Application in Dye‐Sensitized Solar Cells
Authors: Tanaka Naoya , Okubo Takashi , Anma Haruho , Kim Kyung Ho , Inuzuka Yoshie , Maekawa Masahiko , Kuroda‐Sowa Takayoshi
Published: May 2013

New mixed‐valence CuI–CuII 1D coordination polymers of the structure [CuI2CuIIX2(Pip‐dtc)2(CH3CN)2]n [Pip‐dtc = piperidine‐1‐carbodithioate; X = Br (1a), I (1b)] containing a dithiocarbamate derivative have been synthesized and structurally characterized by X‐ray diffraction. The 1D infinite chains were formed from mononuclear copper units [Cu(Pip‐dtc)2] connected by bromido‐ or iodido‐bridged copper dinuclear units that include acetonitrile ligands {i.e., [Cu2X2(CH3CN)2]}. Evaluation of the magnetic properties of 1a and 1b revealed that these complexes displayed relatively strong antiferromagnetic interactions [J = –20.4 cm–1 (1a) and J = –18.8 cm–1 (1b)] between unpaired electrons of the copper(II) ions through the dinuclear halido–copper(I) units. Impedance spectroscopy revealed that complexes 1a and 1b exhibit intriguing semiconducting properties at activation energies of Ea = 0.78 eV (1a) and Ea = 0.62 eV (1b). Coordination polymers 1a and 1b were then adopted as the sensitizing material in dye‐sensitized solar cells (DSSCs).
Synthesis, Characterization and Applications of a New Prussian Blue Type Material
Authors: Qu Jianying , Kang Shiping , Du Xueping , Lou Tongfang , Qu Jianhang
Published: May 2013

This work reports on a material synthesized via 1‐butyl‐3‐methylimidazolium tetrachloroferrate and K3[Fe(CN)6]. Its structure and properties were characterized by IR, XPS, AFM and CV, which was inferred as Prussian Blue Type (PBT) material with particle size distribution between 80–120 nm and spike‐like aggregation from the characterization results. PBT is insoluble in acetone, water and ethanol uniformly, which gives magnetic properties. It can be reacted with 30 % H2O2, and produce gas bubbles when a voltage is applied. Modified on the glassy carbon electrode, the material showed obviously electrocatalytic activity to sodium nitrite, which has potential application prospect for sensors.
Multianalyte Microphysiometry of Macrophage Responses to Phorbol Myristate Acetate, Lipopolysaccharide, and Lipoarabinomannan
Authors: Kimmel Danielle W. , Meschievitz Mika E. , Hiatt Leslie A. , Cliffel David E.
Published: May 2013

This study examined the hypothesis that mycobacterial antigens generate different metabolic responses in macrophages as compared to gram‐negative effectors and macrophage activators. To this end, we utilized platinum electrodes and a light addressable potentiometric sensor to observe dynamic electrochemical changes in metabolic flux, as well as extracellular acidification. While phorbol myristate acetate (PMA) is commonly used to study macrophage activation, the concentration used to create this physiological response varies. The response of RAW‐264.7 macrophages is concentration‐dependent, where the metabolic response to high concentrations of PMA decreases suggesting deactivation. The gram‐negative effector, lipopolysaccharide (LPS), was seen to promote oxygen production which was used to produce a delayed onset of oxidative burst. Pre‐incubation with interferon‐γ (IFN‐γ) allowed a synergistic effect between IFN‐γ and LPS, allowing immediate initiation of oxidative burst. These studies exhibited a stark contrast with lipoarabinomannan (LAM), an antigenic glycolipid component associated with the bacterial genus Mycobacterium. The presence of LAM effectively inhibits any metabolic response preventing consumption of glucose and oxygen for the promotion of oxidative burst and to ensure pathogenic proliferation. This study demonstrates for the first time the immediate inhibitory metabolic effects LAM has on macrophages, suggesting implications for future intervention studies with Mycobacterium tuberculosis.
Wavelet‐based data compression for flow simulation on block‐structured Cartesian mesh
Authors: Sakai Ryotaro , Sasaki Daisuke , Obayashi Shigeru , Nakahashi Kazuhiro
Published: May 2013

A data compression method based on image encoding techniques is presented for a flow simulation data set. An input flow field data set is converted into the octree structure by discrete wavelet transform, and then quantized finely or coarsely depending on its importance in the flow field. Embedded zerotree wavelet encoding as the image encoding technique and entropy encoding reduce the data size by making use of the octree structure created previously. The present compression method is incorporated in a block‐structured Cartesian mesh method called Building‐Cube method. The Building‐Cube method gives not only good performance in the flow simulation but also consistency with the embedded zerotree wavelet encoding in the data compression. Three compression cases for incompressible and compressible flow simulations, including a large‐scale simulation with O(10 8) mesh points, demonstrate that the present compression method gives both high compression ratios and good qualities of compressed data. Copyright © 2013 John Wiley & Sons, Ltd.
Using Phenotypic Heterogeneity to Increase the Power of Genome‐Wide Association Studies: Application to Age at Onset of Ischaemic Stroke Subphenotypes
Authors: Traylor Matthew , Bevan Steve , Rothwell Peter M. , Sudlow Cathie , Dichgans Martin , Markus Hugh S. , Lewis Cathryn M.
Published: May 2013

Genome‐wide association studies (GWAS) have been successful in identifying common variants related to complex disorders. However, some disorders have proved resistant to this strategy with few associations confirmed, despite evidence from twin and family studies of a genetic component. Sophisticated strategies that account for phenotypic heterogeneity may be required to uncover these genetic contributions. Age at onset is an example of a potential source of this heterogeneity in ischaemic stroke. We explore the contribution of age at onset in the Wellcome Trust Case‐Control Consortium 2 ischaemic stroke study. We first examine four established stroke loci in younger onset cases. We extend this to all single‐nucleotide polymorphisms (SNPs) genome‐wide, testing for stronger association signals in younger subsets of cases. Finally, we estimate the pseudoheritability accounted for by common SNPs present on genome‐wide genotyping arrays for cases stratified by age at onset. We find evidence for stronger associations in younger onset cases for the four established stroke loci. Genome‐wide, in cardioembolic and small vessel stroke subphenotypes, a significant number of SNPs show stronger association P‐values when the oldest cases are removed. Finally, we show that the pseudoheritability estimated by common SNPs in cardioembolic stroke increased from 16.5% for older onset cases to 28.5% for younger onset cases. Our results indicate that age at onset is a valuable measure for case ascertainment and in analysis of GWAS in ischaemic stroke: focussing on younger cases who may have a stronger genetic predisposition increases power to detect associations.
An ocean coupling potential intensity index for tropical cyclones
Authors: Lin I.‐I. , Black P. , Price J. F. , Yang C.‐Y. , Chen S. S. , Lien C.‐C. , Harr P. , Chi N.‐H. , Wu C.‐C. , D'Asaro E. A.
Published: May 2013

Timely and accurate forecasts of tropical cyclones (TCs, i.e., hurricanes and typhoons) are of great importance for risk mitigation. Although in the past two decades there has been steady improvement in track prediction, improvement on intensity prediction is still highly challenging. Cooling of the upper ocean by TC‐induced mixing is an important process that impacts TC intensity. Based on detail in situ air‐deployed ocean and atmospheric measurement pairs collected during the Impact of Typhoons on the Ocean in the Pacific (ITOP) field campaign, we modify the widely used Sea Surface Temperature Potential Intensity (SST_PI) index by including information from the subsurface ocean temperature profile to form a new Ocean coupling Potential Intensity (OC_PI) index. Using OC_PI as a TC maximum intensity predictor and applied to a 14 year (1998–2011) western North Pacific TC archive, OC_PI reduces SST_PI‐based overestimation of archived maximum intensity by more than 50% and increases the correlation of maximum intensity estimation from r2 = 0.08 to 0.31. For slow‐moving TCs that cause the greatest cooling, r2 increases to 0.56 and the root‐mean square error in maximum intensity is 11 m s−1. As OC_PI can more realistically characterize the ocean contribution to TC intensity, it thus serves as an effective new index to improve estimation and prediction of TC maximum intensity.
Source‐rupture process of the 2011 Ibaraki‐oki, Japan, earthquake (Mw 7.9) estimated from the joint inversion of strong‐motion and GPS Data: Relationship with seamount and Philippine Sea Plate
Authors: Kubo Hisahiko , Asano Kimiyuki , Iwata Tomotaka
Published: May 2013

The source‐rupture process of the 2011 Ibaraki‐oki earthquake was estimated from the joint inversion of the strong‐motion and global positioning system (GPS) data. The estimated seismic moment and maximum slip are 7.8 × 1020 Nm (Mw 7.9) and 6.3 m, respectively. The total rupture duration is approximately 30 s. The derived source model has one large slip area, which is surrounded by the subducted seamount and the northeastern edge of the Philippine Sea plate. From this model, we concluded that the rupture propagation of the 2011 Ibaraki‐oki earthquake was stopped by the seamount and the Philippine Sea plate. We also showed the possibility of the rupture of this event being the reactivation of the preexisting asperity of an event that occurred in 1923.
Blockade of BDNF signaling turns chemically‐induced long‐term potentiation into long‐term depression
Authors: Montalbano A. , Baj G. , Papadia D. , Tongiorgi E. , Sciancalepore M.
Published: May 2013

Long‐term potentiation (LTP) is accompanied by increased spine density and dimensions triggered by signaling cascades involving activation of the neurotrophin brain‐derived neurotrophic factor (BDNF) and cytoskeleton remodeling. Chemically‐induced long‐term potentiation (c‐LTP) is a widely used cellular model of plasticity, whose effects on spines have been poorly investigated. We induced c‐LTP by bath‐application of the N‐methyl‐d‐aspartate receptor (NMDAR) coagonist glycine or by the K+ channel blocker tetraethylammonium (TEA) chloride in cultured hippocampal neurons and compared the changes in dendritic spines induced by the two models of c‐LTP and determined if they depend on BDNF/TrkB signaling. We found that both TEA and glycine induced a significant increase in stubby spine density in primary and secondary apical dendrites, whereas a specific increase in mushroom spine density was observed upon TEA application only in primary dendrites. Both TEA and glycine increased BDNF levels and the blockade of tropomyosin‐receptor‐kinase receptors (TrkRs) by the nonselective tyrosine kinase inhibitor K‐252a or the selective allosteric TrkB receptor (TrkBR) inhibitor ANA‐12, abolished the c‐LTP‐induced increase in spine density. Surprisingly, a blockade of TrkBRs did not change basal spontaneous glutamatergic transmission but completely changed the synaptic plasticity induced by c‐LTP, provoking a shift from a long‐term increase to a long‐term depression (LTD) in miniature excitatory postsynaptic current (mEPSC) frequency. In conclusion, these results suggest that BDNF/TrkB signaling is necessary for c‐LTP‐induced plasticity in hippocampal neurons and its blockade leads to a switch of c‐LTP into chemical‐LTD (c‐LTD). © 2013 Wiley Periodicals, Inc.
Induction of CaSR expression circumvents the molecular features of malignant CaSR null colon cancer cells
Authors: Singh Navneet , Chakrabarty Subhas
Published: May 2013

We recently reported on the isolation and characterization of calcium sensing receptor (CaSR) null human colon cancer cells (Singh et al., Int J Cancer 2013; 132: 1996–2005). CaSR null cells possess a myriad of molecular features that are linked to a highly malignant and drug resistant phenotype of colon cancer. The CaSR null phenotype can be maintained in defined human embryonic stem cell culture medium. We now show that the CaSR null cells can be induced to differentiate in conventional culture medium, regained the expression of CaSR with a concurrent reversal of the cellular and molecular features associated with the null phenotype. These features include cellular morphology, expression of colon cancer stem cell markers, expression of survivin and thymidylate synthase and sensitivity to fluorouracil. Other features include the expression of epithelial mesenchymal transition linked molecules and transcription factors, oncogenic miRNAs and tumor suppressive molecule and miRNA. With the exception of cancer stem cell markers, the reversal of molecular features, upon the induction of CaSR expression, is directly linked to the expression and function of CaSR because blocking CaSR induction by shRNA circumvented such reversal. We further report that methylation and demethylation of the CaSR gene promoter underlie CaSR expression. Due to the malignant nature of the CaSR null cells, inclusion of the CaSR null phenotype in disease management may improve on the mortality of this disease. Because CaSR is a robust promoter of differentiation and mediates its action through diverse mechanisms and pathways, inactivation of CaSR may serve as a new paradigm in colon carcinogenesis.
Writing “Voiced” Arguments About Science Topics
Authors: Monahan Mary Beth
Published: May 2013

This teacher‐research study responds to the Common Core State Standards (CCSS) call for an integrated model of literacy that simultaneously builds deep content knowledge and develops students' proficiency in writing arguments in science. The author notes that while argument is a cornerstone of the CCSS writing standards, little attention is paid to the issue of “voice.” Asserting that voice is often what makes arguments compelling, the author urges teachers to engage students in the formal study of “voice” while teaching opinion/argumentative writing. The author describes a “science sleuth” simulation unit she implemented to help students perform the production strategies necessary for composing “voiced” scientific arguments. Using grounded theory methodology, the author presents student writing samples to spotlight the challenges, benefits and potential pitfalls of encouraging sixth graders to write scientific arguments with voice—authority, conviction, commitment, and a command of the subject matter.
Association of serum fibroblast growth factor 23 (FGF23) and incident fractures in older men: The Osteoporotic Fractures in Men (MrOS) study
Authors: Lane Nancy E , Parimi Neeta , Corr Maripat , Yao Wei , Cauley Jane A , Nielson Carrie M , Ix Joseph H , Kado Deborah , Orwoll Eric ,   for the Osteoporotic Fractures in Men (MrOS) Study Group
Published: May 2013

Normal mineral metabolism is critical for skeletal integrity, and recently serum fibroblast growth factor 23 (FGF23) levels were found to be directly related to overall fracture risk in elderly Swedish men. To confirm this association, we performed a prospective case-cohort study to understand the relation of FGF23 and fracture risk in older white men enrolled in the Osteoporotic Fractures in Men (MrOS) study. In the cohort of 5994 men attending the baseline MrOS examination, we evaluated a subgroup of 387 men with incident nonvertebral fracture including 73 hip fractures and a sample of 1385 men randomly selected from the cohort with baseline mineral and calcium hormone measurements. FGF23 was measured in baseline serum samples by ELISA (Millipore, Billerica, MA, USA). Modified Cox proportional hazards models that account for case-cohort study design were used to estimate the relative hazards (RH) of fracture in men across quartiles of FGF23. Subjects were also stratified by renal function, and RH per strata was estimated in men with the highest quartile of FGF23 compared with quartiles 3, 2, and 1. Overall, there was no difference in risk of nonspine or hip fracture by baseline FGF23. However, associations differed by strata of eGFRCrCy. Among men with eGFRCrCys <60 mL/min/1.73 m2 (n = 73/313 nonspine fractures), the RH in the highest quartile of FGF23 compared with the rest was 2.02 (95% confidence interval [CI] 1.07–3.79), but in men with eGFRCrCy, >60 mL/min/1.73 m2 (304/1370 fractures) the RH was 0.91 (95% CI 0.66–1.25) after adjustment for age, clinic site, body mass index, race, total hip bone mineral density, vitamin D, parathyroid hormone, alcohol use, physical activity, fracture history, and serum phosphorus. Serum FGF23 levels are not associated with incident fractures in elderly men overall. However, higher levels of serum FGF23 are associated with fracture risk in those with poor renal function. © 2013 American Society for Bone and Mineral Research.
Hepatitis C Co-infection and Severity of Liver Disease as Risk Factors for Osteoporotic Fractures Among HIV-Infected Patients
Authors: Maalouf Naim M , Zhang Song , Drechsler Henning , Brown Geri R , Tebas Pablo , Bedimo Roger
Published: May 2013

Osteoporosis is increasingly reported in the aging HIV-positive population, and co-infection with hepatitis C virus (HCV) may further increase the risk of osteoporosis. However, it remains unclear whether HCV-related increased fracture risk is a function of the severity of liver disease. We calculated the time-updated alanine aminotransferase to platelet ratio index (APRI) score (an indirect marker of hepatic fibrosis) in all HIV-infected patients enrolled in the Veterans Affairs' Clinical Case Registry between 1984 and 2009. The association between HCV co-infection and incident osteoporotic fracture (defined as closed wrist, vertebral, or hip fracture) was assessed in univariate and multivariate Cox survival models adjusting for traditional risk factors for osteoporosis and APRI score or the presence of cirrhosis. A total of 772 osteoporotic fractures were identified among 56,660 HIV-infected patients (98.1% male; 31.3% HCV co-infected; median age 44.0 years) contributing 305,237 patient-years of follow-up. Fracture rates were significantly higher among HIV/HCV patients than HIV-only patients (2.57 versus 2.07/1000 patient-years, relative risk = 1.24, p < 0.0001). In a Cox multivariable model including age, race, smoking, drug use, body mass index, and antiretroviral therapy, HCV co-infection remained an independent predictor of osteoporotic fractures after controlling for presence of cirrhosis (hazard ratio [HR] = 1.32; p < 0.001) or APRI score (HR = 1.30; p = 0.003). Among HIV/HCV co-infected patients, cirrhosis strongly predicted osteoporotic fractures (HR = 1.65; 95% confidence interval [CI] 1.11–2.44; p = 0.012), but APRI score was a weaker predictor (HR = 1.008; 95% CI 1.002–1.014; p = 0.015). In conclusion, among HIV-infected patients, severity of liver disease partly explains the HCV-associated increased risk of osteoporotic fractures. Other determinants of this increased risk remain to be defined. © 2013 American Society for Bone and Mineral Research.
Hox Gene Deformed is likely involved in mandibular regression during presoldier differentiation in the nasute termite Nasutitermes takasagoensis
Authors: Toga Kouhei , Saiki Ryota , Maekawa Kiyoto
Published: May 2013

Division of labor is a distinguishing characteristic of eusocial insects. To understand the proximate factors underlying caste determination, it is essential to clarify the developmental mechanisms during the differentiation of each caste. Termite soldiers have species‐specific and diverse morphologies that are specialized for colony defense. Soldiers of the subfamily Nasutitermitinae (Termitidae), one of the most derived termite groups, possess a long, horn‐like frontal projection (nasus), an invaginated glandular structure in the head (frontal gland), and regressed mandibles. These morphological changes occur prior to the molt into presoldiers (the preceding stage of soldiers). In Drosophila and other insects, Hox genes determine segment identities; thus they might be involved in such body‐part‐specific modifications during soldier differentiation. Deformed (Dfd) functions not only in the formation of the mandible and maxilla but also in other head parts (e.g., eye‐antennal disc) in other insects. In this study, we examined Dfd functions in nasus/frontal gland formation and mandibular regression in Nasutitermes takasagoensis. Relative expression analyses showed that Dfd expression levels in the mouthparts were significantly higher than those in any other body parts of workers before presoldier molt. Dfd RNA interference resulted in the inhibition of mandibular regression during presoldier differentiation, but nasus and frontal gland formation were not affected. These results suggest that Dfd is involved in the determination of mandibular positional information and specific modification during presoldier differentiation in N. takasagoensis. This is the first work to show the effects of Hox genes on caste‐specific morphogenesis in social insects. J. Exp. Zool. (Mol. Dev. Evol.) 320B: 385–392, 2013. © 2013 Wiley Periodicals, Inc.
Association of solar wind proton flux extremes with pseudostreamers
Authors: Zhao L. , Gibson S. E. , Fisk L. A.
Published: May 2013

We investigate the characteristics and solar origins of a subpopulation of the solar wind that possesses extreme values of proton flux. Ulysses observations including solar wind magnetic flux, proton flux, number density and velocity, and ionic composition are examined in this study. We find that the departures of solar wind proton flux from its constancy occur for time intervals leading up to and encompassing the past two solar minima, and the extreme‐proton‐flux wind possesses the following characteristics: (1) it generally originates from sources middle‐distant from the Heliospheric Current Sheet (HCS); (2) it is associated with a broad range of velocities and electron temperatures but excludes very fast/cold wind; (3) it exhibits anticorrelation between electron temperature and proton velocity, as does the rest of the solar wind; (4) it has extreme proton density values relative to the rest of the solar wind; and (5) the extreme‐high‐proton‐flux wind has radial component of open magnetic flux (Br) greater than the rest of the solar wind, and both extreme‐high and extreme‐low wind do not possess the lowest values of Br flux. Comparing with SOHO EIT 195 Å coronal images, we find the observed extreme‐proton‐flux wind has temporal and spatial coincidence with the appearance of low‐latitude coronal holes present in the recent two solar minima; the magnetic field lines extrapolated by the Potential Field Source Surface model confirm there are coronal pseudostreamer structures involved. So we propose that these extreme‐proton‐flux winds can be associated with mid‐ to low‐latitude coronal holes and “pseudostreamer” structures.
Source properties of dynamic rupture pulses with off‐fault plasticity
Authors: Gabriel A.‐A. , Ampuero J.‐P. , Dalguer L. A. , Mai P. M.
Published: May 2013

Large dynamic stresses near earthquake rupture fronts may induce an inelastic response of the surrounding materials, leading to increased energy absorption that may affect dynamic rupture. We systematically investigate the effects of off‐fault plastic energy dissipation in 2‐D in‐plane dynamic rupture simulations under velocity‐and‐state‐dependent friction with severe weakening at high slip velocity. We find that plasticity does not alter the nature of the transitions between different rupture styles (decaying versus growing, pulse‐like versus crack‐like, and subshear versus supershear ruptures) but increases their required background stress and nucleation size. We systematically quantify the effect of amplitude and orientation of background shear stresses on the asymptotic properties of self‐similar pulse‐like ruptures: peak slip rate, rupture speed, healing front speed, slip gradient, and the relative contribution of plastic strain to seismic moment. Peak slip velocity and rupture speed remain bounded. From fracture mechanics arguments, we derive a nonlinear relation between their limiting values, appropriate also for crack‐like and supershear ruptures. At low background stress, plasticity turns self‐similar pulses into steady state pulses, for which plastic strain contributes significantly to the seismic moment. We find that the closeness to failure of the background stress state is an adequate predictor of rupture speed for relatively slow events. Our proposed relations between state of stress and earthquake source properties in the presence of off‐fault plasticity may contribute to the improved interpretation of earthquake observations and to pseudodynamic source modeling for ground motion prediction.
Evidence for geomagnetic excursions recorded in Brunhes and Matuyama Chron lavas from the trans‐Mexican volcanic belt
Authors: Michalk Daniel M. , Böhnel Harald N. , Nowaczyk Norbert R. , Aguírre‐Diaz Gerardo J. , López‐Martínez Margarita , Ownby Steven , Negendank Jörg F. W.
Published: May 2013

This study presents paleomagnetic data from 59 independent lava flows from the trans‐Mexican volcanic belt (TMVB) with ages from 6.4 Ma to recent, 52 being younger than 1 Ma, and 11 new40Ar/39Ar age determinations. Most remanence carriers are Ti‐poor titanomagnetite of pseudosingle‐domain magnetic structure, nine lavas contain small amounts of titanomaghemite, and four lavas additional (titano‐) hematite. Paleosecular variation of lava flows younger than 1.7 Ma is consistent with latitude‐dependent Model G and also in agreement with other Pleistocene paleomagnetic data from the TMVB. The directional record of Brunhes and Matuyama Chrons lavas was correlated to the geomagnetic polarity timescale and there is evidence for at least four geomagnetic excursions. One lava flow dated at 592 ± 20 ka has a fully reversed paleodirection and most likely erupted during the Big Lost excursion. Another fully reversed flow, dated at 671 ± 12 ka, gives new volcanic evidence for the Delta/Stage 17 excursion. This excursion is supported by a reversed intermediate direction of another flow from a different volcanic field but of very close age of 673 ± 10 ka. From the Matuyama age lavas, one flow with normal polarity magnetization, dated at 949 ± 37 ka, could either be related to the Kamikatsura or the Santa Rosa excursion and a normal polarity flow, dated at 1628 ± 56 ka, could have been emplaced during the Gilsa excursion. The results presented here confirm in one case but disagree in four cases with results presented in two previous studies of the same lava flows and interpreted as geomagnetic excursions.
Validation of AIRS/AMSU‐A water vapor and temperature data with in situ aircraft observations from the surface to UT/LS from 87°N–67°S
Authors: Diao Minghui , Jumbam Loayeh , Sheffield Justin , Wood Eric F. , Zondlo Mark A.
Published: May 2013

Validation of the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit (AMSU‐A) data set with in situ observations provides useful information on its application to climate and weather studies. However, different space/time averaging windows have been used in past studies, and questions remain on the variation of errors in space, such as between land/ocean and the Northern/Southern Hemispheres. In this study, in situ aircraft measurements of water vapor and temperature are compared with the AIRS/AMSU‐A retrievals (Version 5 Level 2) from 87°N to 67°S and from the surface to the upper troposphere and lower stratosphere (UT/LS). By using a smaller comparison window (1 h and 22.5 km) than previous studies, we show that the absolute percentage difference of water vapor (|dH2Operc|) is ~20–60% and the absolute temperature difference (|dTemp|) is ~1.0–2.5 K. The land retrievals show improvements versus Version 4 by ~5% in water vapor concentration and ~0.2 K in temperature at 200–800 mbar. The land (ocean) retrievals are colder and drier (warmer and moister) than the in situ observations in the boundary layer, warmer and drier (warmer and moister) at the UT/LS. No significant differences between hemispheres are noted. Overall, future comparisons are suggested to be done within 4 h and 100 km in order to keep the errors from window sizes within ~10%. To constrain the uncertainties in previous validation results, we show that every 22.5 km (or 1 h) increment in window sizes contributes to ~2% |dH2Operc| and ~0.1 K |dTemp| increases.
Natural land carbon dioxide exchanges in the ECMWF integrated forecasting system: Implementation and offline validation
Authors: Boussetta Souhail , Balsamo Gianpaolo , Beljaars Anton , Panareda Anna‐Agusti , Calvet Jean‐Christophe , Jacobs Cor , van den Hurk Bart , Viterbo Pedro , Lafont Sebastien , Dutra Emanuel , Jarlan Lionel , Balzarolo Manuela , Papale Dario , van der Werf Guido
Published: May 2013

The European Centre for Medium‐Range Weather Forecasts land surface model has been extended to include a carbon dioxide module. This relates photosynthesis to radiation, atmospheric carbon dioxide (CO2) concentration, soil moisture, and temperature. Furthermore, it has the option of deriving a canopy resistance from photosynthesis and providing it as a stomatal control to the transpiration formulation. Ecosystem respiration is based on empirical relations dependent on temperature, soil moisture, snow depth, and land use. The CO2 model is designed for the numerical weather prediction (NWP) environment where it benefits from good quality meteorological input (i.e., radiation, temperature, and soil moisture). This paper describes the CO2 model formulation and the way it is optimized making use of off‐line simulations for a full year of tower observations at 34 sites. The model is then evaluated against the same observations for a different year. A correlation coefficient of 0.65 is obtained between model simulations and observations based on 10 day averaged CO2 fluxes. For sensible and latent heat fluxes there is a correlation coefficient of 0.80. To study the impact on atmospheric CO2, coupled integrations are performed for the 2003 to 2008 period. The global atmospheric growth is well reproduced. The simulated interannual variability is shown to reproduce the observationally based estimates with a correlation coefficient of 0.70. The main conclusions are (i) the simple carbon dioxide model is highly suitable for the numerical weather prediction environment where environmental factors are controlled by data assimilation, (ii) the use of a carbon dioxide model for stomatal control has a positive impact on evapotranspiration, and (iii) even using a climatological leaf area index, the interannual variability of the global atmospheric CO2 budget is well reproduced due to the interannual variability in the meteorological forcing (i.e., radiation, precipitation, temperature, humidity, and soil moisture) despite the simplified or missing processes. This highlights the importance of meteorological forcing but also cautions the use of such a simple model for process attribution.
Functional MRI in conscious rats using a chronically implanted surface coil
Authors: Martin Chris J. , Kennerley Aneurin J. , Berwick Jason , Port Michael , Mayhew John E.W.
Published: May 2013

Purpose

To establish procedures for functional MRI (fMRI) in rats without the need for anesthetic agents.

Materials and Methods

Rats were trained to habituate to restraint in a harness and scanner noise. Under anesthesia, rats were then prepared with a cranial implant that permitted stabilization of the head during subsequent imaging experiments. The cranial implant included an radiofrequency (RF) coil that was used to transmit and receive radiofrequency signals during imaging. Further training was then conducted to habituate the animals to head fixation whilst in the MR scanner.

Results

Using this method, we were able to successfully and repeatedly record BOLD fMRI responses to hypercapnia and whisker stimulation in awake rats. Electrical stimulation of the whisker pad produced a ∼7% increase in BOLD signal in the corresponding barrel cortex as well as adjacent negative BOLD responses, whilst hypercapnia produced larger increases in BOLD signal amplitude.

Conclusion

This methodology leaves the face and limbs free from obstruction, making possible a range of behavioral or sensory stimulation protocols. Further development of this animal model could enable traditional behavioral neuroscience techniques to be combined with modern functional neuroimaging. J. Magn. Reson. Imaging 2013;38:739–744. © 2013 Wiley Periodicals, Inc.
A simple method to prepare the magnetic Ni@Au core‐shell nanostructure for the cycle surface enhanced Raman scattering substrates
Authors: Ding Qianqian , Ma Yongmei , Ye Yingjie , Yang Liangbao , Liu Jinhuai
Published: May 2013

We have developed a simple and efficient approach to synthesize Ni@Au core‐shell nanostructures using the simple redox transmetalation reaction. The as‐synthesized nanomaterial with clean and reproducible properties was used as the surface enhanced Raman scattering (SERS) substrate. In addition, these nanostructures are stable for at least a 30‐day period, and the long‐term stability is of the great importance in practical application. The magnetic behavior serves as an added advantage of its easy separation from the analytes. So that it can be reused. This novel multifunctional hybrid nanostructure will open up an exciting opportunity in multiple uses SERS measures. Copyright © 2013 John Wiley & Sons, Ltd.
2D‐IR spectroscopy: an additional dimension to investigate ultrafast structural dynamics
Authors: Lima Manuela , Candelaresi Marco , Foggi Paolo
Published: May 2013

We describe the theory, some experimental details and the data analysis procedures of two‐dimensional infrared (2D‐IR) spectroscopy. A brief description of an application of the technique to the study of a dipeptide in solution is also reported. Like multi‐dimensional NMR spectroscopy, 2D‐IR can provide additional pieces of information hidden in the inhomogenously broadened bands observed in linear IR spectra. In addition, the presence of off‐diagonal peaks allows a direct estimate of the couplings between vibrational modes. By means of this technique, making use of ultrashort mid‐infrared pulses, exploration of the structure and of the dynamics of molecular systems in the condensed phase and on very short time scales becomes now achievable. The effects of solvent dynamics on Glycine‐L‐Alanine‐Methylamide by 2D‐IR are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
Facile Fabrication of Chemically Grafted Graphene Oxide–Poly(glycidyl methacrylate) Composite Microspheres and Their Electrorheology
Authors: Zhang Wen Ling , Choi Hyoung Jin , Seo Yongsok
Published: May 2013

This paper reports a facile approach for fabricating core‐shell structured graphene oxide (GO)‐wrapped amine‐modified poly(glycidyl methacrylate) (ami‐PGMA) microspheres. The resulting core‐shell structure is confirmed by scanning electron micsroscopy (SEM) and transmission electron microscopy (TEM), whereas the coexistence of GO and PGMA is confirmed by FTIR spectroscopy. The thermal stability of the ami‐PGMA/GO microspheres is enhanced compared with that of pure PGMA microspheres. The novel ami‐PGMA/GO composite microsphere‐based electrorheological (ER) fluid shows typical ER characterization, using a rotational rheometer under an applied electric field. The dielectric analysis results along with the relaxation time and achievable polarizability of the fluid are correlated with the ER performance using a LCR meter.

magnified image
Polysaccharide‐Based Polyanion–Polycation–Polyanion Ternary Systems in the Concentrated Regime and Hydrogel Form
Authors: Marsich Eleonora , Travan Andrea , Feresini Massimo , Lapasin Romano , Paoletti Sergio , Donati Ivan
Published: May 2013

In the field of bioactive biomaterials, multi‐biopolymer systems are of particular interest as they represent potential extra cellular matrix (ECM) mimics. Ternary mixtures composed of alginate, hyaluronan, and a lactose‐modified chitosan undergo a rheological investigation that reveal the presence of polyanion‐polycation supramolecular structures, which dissolve once the third (polyanion) component is added. Two selected ternary mixtures are used for the preparation of calcium–alginate hydrogels and their mechanical performance and stability are found to be strongly influenced by the relative composition in terms of the two non‐gelling components. The presence in the mixture of bioactive polysaccharides leads to a notable improvement in the proliferation of primary culture of chondrocytes.

magnified image
Active Poly(4‐chloromethyl styrene)‐Functionalized Multiwalled Carbon Nanotubes
Authors: Chen Xianhong , Zhou Mi , Hou Qinglin , Tu Xi , Wu Xiaoli
Published: May 2013

Concentrated nitric acid‐treated multiwalled carbon nanotubes (MWCNTs) are functionalized with active poly(4‐chloromethyl styrene) (PCMS) through the esterification reaction of the carboxyl groups of the former and the p‐benzyl chloride groups of the latter in the presence of a phase‐transfer catalyst. Characterization using Raman spectroscopy, Fourier transform infrared spectroscopy, and hydrogen nuclear magnetic resonance spectroscopy demonstrates that the active PCMS chains are chemically tethered onto the side walls (or surfaces) of the MWCNTs. The core‐shell nanostructure of active PCMS‐modified MWCNTs (MWCNT‐PCMS) can be observed by high resolution transmission electron microscopy, and the amount of PCMS present is 31.3 wt% by thermogravimetric analysis. Solubility testing shows that MWCNT‐PCMS dissolves well in tetrahydrofuran, chloroform, toluene, and N,N‐dimethylformamide, and the maximum nanotube concentration in toluene is 413 mg L−1.

magnified image
The Use of Rule‐Based and QSPR Approaches in ADME Profiling: A Case Study on Caco‐2 Permeability
Authors: Pham‐The Hai , González‐Álvarez Isabel , Bermejo Marival , Garrigues Teresa , Le‐Thi‐Thu Huong , Cabrera‐Pérez Miguel Ángel
Published: May 2013

During the early ADME profiling the development of simple, interpretable and reliable in silico tools is very important. In this study, rule‐based and QSPR approaches were investigated using a large Caco‐2 permeability database. Three permeability classes were determined: high (H), moderate (M) and low (L). The main physicochemical properties related with permeability were ranked as follows: Polar Surface Area (PSA)>Lipophilicity (logP/logD)>Molecular Weight (MW)>number of Hydrogen Bond donors and acceptors>Ionization State>number of Rotatable Bonds>number of Rings. The best rule, based on the combination of PSA‐MW‐logD (3PRule), was able to identify the H, M and L classes with accuracy of 72.2, 72.9 and 70.6 %, respectively. Subsequently, a consensus system based on three voting binary classification trees was constructed. It accurately predicted 78.4/76.1/79.1 % of H/M/L compounds on training and 78.6/71.1/77.6 % on test set. Finally, the 3PRule and multiclassifier were validated with 23 drugs in a Caco‐2 assay. The rule is very useful to improve assay design and prioritize the high absorption candidates. Meanwhile the QSPR model exhibits appropriate classification performance. Due to the simplicity, easy interpretation and accuracy, the 3PRule and consensus model developed here can be used in early ADME profiling.
The Acid/Base Profile of the Human Metabolome and Natural Products
Authors: Manallack David T. , Dennis Matthew L. , Kelly Mark R. , Prankerd Richard J. , Yuriev Elizabeth , Chalmers David K.
Published: May 2013

Human small molecule metabolites (the human metabolome) are a set of compounds that interact with at least one macromolecule in the biosphere. This study investigates the acid/base profile of the human metabolome, natural products and drugs, together with an analysis of their physicochemical properties. Ionisation constants (pKa values) are estimated for each compound and the identity of the ionisable functional groups in each set is determined. The acid/base and physicochemical property profile of the lipid component of the metabolome differed considerably to the other datasets. In contrast, the acid/base properties of non‐lipid metabolites were found to be similar to both drugs and natural products. While the non‐lipid metabolites have lower average ClogP values and more hydrogen bond donors than the other datasets, the distribution of physicochemical property values overlapped considerably with the drug dataset. Considering also that the non‐lipid metabolites are of biochemical interest, their characteristics have great potential to influence the selection of screening compounds for drug discovery.
Information Theory and Voting Based Consensus Clustering for Combining Multiple Clusterings of Chemical Structures
Authors: Saeed Faisal , Salim Naomie , Abdo Ammar
Published: May 2013

Many consensus clustering methods have been applied in different areas such as pattern recognition, machine learning, information theory and bioinformatics. However, few methods have been used for chemical compounds clustering. In this paper, an information theory and voting based algorithm (Adaptive Cumulative Voting‐based Aggregation Algorithm A‐CVAA) was examined for combining multiple clusterings of chemical structures. The effectiveness of clusterings was evaluated based on the ability of the clustering method to separate active from inactive molecules in each cluster, and the results were compared with Ward’s method. The chemical dataset MDL Drug Data Report (MDDR) and the Maximum Unbiased Validation (MUV) dataset were used. Experiments suggest that the adaptive cumulative voting‐based consensus method can improve the effectiveness of combining multiple clusterings of chemical structures.
Chemotherapy‐induced prospective memory impairment in patients with breast cancer
Authors: Cheng Huaidong , Yang Zhen , Dong Biao , Chen Chanjuan , Zhang Mingjun , Huang Zhonglian , Chen Zhendong , Wang Kai
Published: May 2013

Objective

This study aimed to investigate the event‐based prospective memory (EBPM) and time‐based prospective memory (TBPM) in chemotherapy‐induced cognitive impairment in patients with breast cancer.

Methods

Forty patients with breast cancer who underwent adjuvant chemotherapy and 40 age‐matched and education‐matched healthy women were administered with a battery of neuropsychological tests including EBPM and TBPM tasks.

Results

A significant difference between breast cancer patients and controls was found in the scores on the mini‐mental state examination (t = −11.684,p < 0.01), verbal fluency test (t = −7.939,p < 0.01), and digit span (t = −2.538,p < 0.05). Compared with healthy controls, breast cancer patients exhibited a poorer performance on EBPM (t = −7.096,p < 0.01) but not on TBPM (t = −1.921,p > 0.05).

Conclusions

Our results suggest that breast cancer patients who had undergone adjuvant chemotherapy show deficits in EBPM but not in TBPM. Copyright © 2013 John Wiley & Sons, Ltd.
EGFR: Tale of the C‐terminal tail
Authors: Gajiwala Ketan S.
Published: May 2013

The carboxy terminal tail of epidermal growth factor receptor (EGFR) plays a critical role in the regulation of the enzyme activity of the kinase. There is a good structural model for the mechanism by which the C‐terminal tail proximal to the kinase domain contributes to the negative regulation of the activity. Its conformation in the active state, conversely, has remained elusive due to its dynamic nature. A recently published structure of EGFR kinase domain shows the conformation of the proximal C‐terminal tail in the active kinase. Analysis of this conformational state of the C‐terminal tail is presented, and some of the mutagenesis data is revisited. © 2013 The Protein Society
Hesperidin Prevents Androgen Deficiency‐induced Bone Loss in Male Mice
Authors: Chiba Hiroshige , Kim Hyounju , Matsumoto Akiyo , Akiyama Satoko , Ishimi Yoshiko , Suzuki Kazuharu , Uehara Mariko
Published: May 2013

The purpose of this study was to examine whether hesperidin inhibits bone loss in androgen‐deficient male mice. Male ddY mice aged 7 weeks underwent either a sham operation or orchidectomy (ORX) and were divided into five groups: a sham‐operated group fed a control diet (Sham) based on AIN‐93G formulation with corn oil instead of soy bean oil, an ORX group fed the control diet (ORX), a group fed the control diet containing 0.5% hesperidin (ORX + H), a group fed the control diet containing 0.7% α‐glucosylhesperidin (ORX + αG), and a group fed the control diet containing 0.013% simvastatin (ORX + St). Four weeks after intervention, ORX mice showed a striking decrease in seminal vesicle weight, which was not affected by the administration of hesperidin, α‐glucosylhesperidin, or simvastatin. Femoral BMD was significantly reduced by ORX, and bone loss was inhibited by the administration of hesperidin, α‐glucosylhesperidin or simvastatin. Histomorphometric analysis showed that the bone volume and trabecular thickness were significantly lower, and the osteoclast number was higher in the distal femoral cancellous bone in the ORX group than in the Sham group, and these were normalized in the ORX + H, ORX + αG and ORX + St groups. These results indicate that hesperidin inhibited bone resorption and hyperlipidemia, in ORX mice, and the preventive effect was stronger than that observed in ovariectomized mice in our previous study. Copyright © 2013 John Wiley & Sons, Ltd.
The direct assimilation of principal components of IASI spectra in the ECMWF 4D‐Var
Authors: Matricardi M. , McNally A. P.
Published: May 2013

The European Centre for Medium‐range Weather Forecasts (ECMWF) 4D‐Var data assimilation system has been modified to allow the direct assimilation of Principal Component (PC) scores derived from spectra measured by the Infrared Atmospheric Sounding Interferometer (IASI). Testing of a prototype system where 165 IASI radiances are replaced by just 20 PC scores shows significant computational savings with no detectable loss of skill in the resulting analyses or forecasts. Indeed in some respects the assimilation of PC scores leads to marginal improvements over the traditional radiance‐based assimilation.
Organometallic Tin Compounds Derived from 2‐Benzimidazole Propionic Acid
Authors: Camacho‐Camacho Carlos , Esparza‐Ruiz Adriana , Peña‐Hueso Adrián , Mijangos Edgar , Ramos‐García Iris , Contreras Rosalinda , Flores‐Parra Angelina
Published: May 2013

Reactions of 2‐benzimidazole propionic acid (1) with [Sn(nBu)3]2O and SnPh3OH gave mononuclear organometallic tin esters 2 and 3, respectively, where 1 is coordinated to the tin atom through the carboxylate group. Further reactions of 2 with DMSO and 3 with methanol, ethanol, pyridine, DMSO, THF and water afforded the corresponding tin compounds coordinated by the base 4–10, respectively. X‐ray diffraction analyses of 5, 6 and 10 were obtained. The solid‐state structures showed that the ligand 1 is bound through both oxygen atoms of the carboxylic group with the Lewis base anti to it. Reaction of 1 with di‐n‐butyltin oxide produced a tetranuclear distannoxane (11) by the association of four Sn(nBu)2 groups, two oxygen atoms and four ligands. Four of the oxygen atoms are tricoordinate. The tin atoms are hexacoordinate with distorted octahedral geometries. The macromolecule has in total seven fused rings. Five of them are four membered rings arranged in a ladder‐type arrangement and the other two are six membered rings. The aliphatic chains and the benzimidazole groups are perpendicularly oriented to the polycyclic arrangement giving a sandwich with polar bonds in the middle and covered by the aliphatic and aromatic groups. In all compounds the ligands showed a chiral helicoidal preferred conformation.