bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioglass/alginate composite hydrogel beads as cell carriers for bone regeneration
Authors: Zeng Qiongyu , Han Yan , Li Haiyan , Chang Jiang
Published: July 2013

Cell carrier is a useful biomedical tool to deliver particular kind of cells to a specific site for cell therapy or tissue regeneration. In the current study, 45S5 bioglass (BG) was introduced into alginate (ALG) to generate BG/ALG composite hydrogel beads as cell carriers. The ions releasing behavior, dimensional stability andin vitrobioactivity of the beads were investigated. Results showed that the BG/ALG beads revealed similar calcium ion releasing behavior as compared with ALG beads. In addition, silicon ion releasing was detected in BG/ALG beads. BG/ALG and ALG beads shared similar dimensional stability, and BG/ALG beads could induce apatite deposition on their surface after being soaked in stimulated body fluid. Then, the effects of ion extracts from hydrogel beads on cell behavior were investigated. Results confirmed that extracts of BG/ALG beads could simulate proliferation and osteogenic differentiation of mesenchymal stem cells as well as angiogenesis of endothelial cells. Furthermore, MC3T3‐E1 cells were successfully encapsulated in hydrogel beads. BG/ALG beads enhanced the cell proliferation and stimulated osteogenic differentiation of the encapsulated MC3T3‐E1 cells as compared with ALG beads. Therefore, BG/ALG composite hydrogel beads loaded with bone forming cells may be useful tools for bone regeneration and tissue engineering applications. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 42–51, 2014.
One‐pot, Green and Efficient Synthesis of 3,4‐Dihydropyrimidin‐2(1H)‐ones or Thiones Catalyzed by Citric Acid
Authors: Ghorbani‐Choghamarani Arash , Taghipour Tahereh , Azadi Gouhar
Published: July 2013

One‐pot three‐component condensation of ethyl acetoacetate, aldehyde and urea or thiourea in refluxing ethanol in the presence of catalytic amounts of citric acid afforded the corresponding 3,4‐dihydropyrimidin‐2(1H)‐ones/thiones in high yields. The catalyst is reusable and can be applied several times without any decrease in product yield.
Fast and Efficient Reductive Amination of Aldehydes by NaBH4/B(OH)3 and NaBH4/Al(OH)3
Authors: Setamdideh Davood , Hasani Samira , Noori Shahla
Published: July 2013

Reductive amination a variety of aldehydes and anilines to their corresponding secondary amines were carried out with NaBH4/B(OH)3 and NaBH4/Al(OH)3 as new reducing systems in CH3CN at room temperature in high to excellent yields of products (90‐96%).
Observations of transverse Z mode and parametric decay in the solar wind
Authors: Kellogg P. J. , Goetz K. , Monson S. J. , Opitz A.
Published: July 2013

The frequency resolution of the Time Domain Samplers of the S/WAVES experiments on the STEREO spacecraft has allowed clear observations of the nature of the Langmuir‐Z‐mode waves observed in the solar Wind in conjunction with Type III radio bursts. These include observations of transverse polarization of what are usually identified as Langmuir waves, observations of three‐wave decay, indications of the cause of the broadening of the spectrum of the observed waves, new understanding of the threshold for the three‐wave‐decay instability, and contributions to the understanding of conversion of these waves to electromagnetic waves. Analysis, using the decay relations, shows that decay often occurs to the Z mode, or near it. Z‐mode waves cannot be produced directly by the electrons of Type III bursts. The damping of Z mode and near Z mode is very small, accounting for the common occurrence of this nonlinear process. In particular, three‐wave parametric decay of a Langmuir wave to another Langmuir wave has become recognized as the dominant nonlinear process for Langmuir waves from Type III bursts. It is found, however, that decay usually leaves much of the wave energy in the daughter wave and that this wave often falls in a region where modulational instability must be considered in addition to three‐wave decay. On rare occasions, further decays follow the first. In these cases, the path length of the stimulating electron beam can sometimes be determined.
The free escape continuum of diffuse ions upstream of the Earth's quasi‐parallel bow shock
Authors: Trattner K. J. , Allegrini F. , Dayeh M. A. , Funsten H. O. , Fuselier S. A. , Heirtzler D. , Janzen P. , Kucharek H. , McComas D. J. , Möbius E. , Moore T. E. , Petrinec S. M. , Reisenfeld D. B. , Schwadron N. A. , Wurz P.
Published: July 2013

The Earth's bow shock is very efficient in accelerating ions out of the incident solar wind distribution to high energies (≈ 200 keV/e). Fluxes of energetic ions accelerated at the quasi‐parallel bow shock, also known as diffuse ions, are best represented by exponential spectra in energy/charge, which require additional assumptions to be incorporated into these model spectra. One of these assumptions is a so‐called “free escape boundary” along the interplanetary magnetic field into the upstream direction. Locations along the IBEX orbit are ideally suited for in situ measurements to investigate the existence of an upstream free escape boundary for bow shock accelerated ions. In this study we use 2 years of ion measurements from the background monitor on the IBEX spacecraft, supported by ACE solar wind observations. The IBEX Background Monitor is sensitive to protons > 14 keV, which includes the energy of the maximum flux for diffuse ions. With increasing distance from the bow shock along the interplanetary magnetic field, the count rates for diffuse ions stay constant for ions streaming away from the bow shock, while count rates for diffuse ions streaming toward the shock gradually decrease from a maximum value to ~1/e at distances of about 10 RE to 14 RE. These observations of a gradual decrease support the transition to a free escape continuum for ions of energy >14 keV at distances from 10 RE to 14 RE from the bow shock.
Influence of mineral fraction on the rheological properties of forsterite + enstatite during grain‐size‐sensitive creep: 2. Deformation experiments
Authors: Tasaka Miki , Hiraga Takehiko , Zimmerman Mark E.
Published: July 2013

In order to understand the effects of secondary minerals on the flow properties of rocks, we have conducted uniaxial compression experiments on polycrystalline forsterite (Fo) + enstatite (En) samples. At constant temperature and strain rate, the flow stress of the samples decreases with increasing enstatite volume fraction ( fEn) for samples with 0 < fEn < 0.5 and increases with increasing fEn for samples with 0.5 < fEn < 1. The values of the preexponential term, stress and grain size exponents, and activation energy in the constitutive equation for a wide range of fEn were determined. Samples with a low fEn(≤0.03) deformed at strain rates of 2 × 10−5 to 2 × 10−4/s exhibit creep characteristics that correspond to dislocation‐accommodated grain boundary sliding creep (i.e., stress exponent, n = 3), whereas diffusion‐accommodated grain boundary sliding creep is typical of high fEn samples (i.e., stress exponent, n = 1). The change of flow strength as a function of fEn during grain‐size‐sensitive creep is primarily due to changes in grain size of both phases and secondarily due to changes in the volume fraction of phases with different flow strengths. Viscosities of all samples can be reproduced in a viscosity model that takes into account (1) the grain sizes estimated by the grain growth laws established in our part 1 paper and (2) flow laws determined for the individual phases, in this case, forsterite and enstatite. Furthermore, we demonstrate that our model can be extended to make predictions of viscosity in other mineral assemblages.
An analysis of diurnal cycles in the mass of ambient aerosols derived from biomass burning and agro‐industry
Authors: Caetano‐Silva L. , Allen A. G. , Lima‐Souza M. , Cardoso A. A. , Campos M. L. A. M. , Nogueira R. F. P.
Published: July 2013

Strong diurnal cycles in ambient aerosol mass were observed in a rural region of Southeast Brazil where the trace composition of the lower troposphere is governed mainly by emissions from agro‐industry. An optical particle counter was used to record size‐segregated aerosol number concentrations between 13 May 2010 and 15 March 2011. The data were collected every 10 min and used to calculate aerosol mass concentrations. Aerosol samples were also collected onto filters during daytime (10:00–16:00 local time) and nighttime (20:00–06:00) periods, for subsequent analysis of soluble ions and water‐soluble organic carbon. Biomass burning aerosols predominated during the dry winter, while secondary aerosols were most important in the summer rainy season. In both seasons, diurnal cycles in calculated aerosol mass concentrations were due to the uptake of water by the aerosols and, to a lesser extent, to emissions and secondary aerosol formation. In neither season could the observed mass changes be explained by changes in the depth of the boundary layer. In the summer, nighttime increases in aerosol mass ranged from 2.7‐fold to 81‐fold, depending on particle size, while in the winter, the range was narrower, from 2.2‐fold to 9.5‐fold, supporting the possibility that the presence of particles derived from biomass burning reduced the overall ability of the aerosols to absorb water.
Evaluation of nonscarred myocardial T1 value using contrast‐enhanced look‐locker cardiac MRI and its relationship to cardiac function in dilated cardiomyopathy: Comparison of 1.5 and 3.0 Tesla MRI
Authors: Tachi Masaki , Amano Yasuo , Kobayashi Yasuhiro , Mizuno Kyoichi , Kumita Shinichiro
Published: July 2013

Purpose

To assess relationship between nonscarred myocardial T1 value measured using contrast‐enhanced Look‐Locker MRI and cardiac function in dilated cardiomyopathy (DCM) at 1.5 Tesla (T) and 3.0T MRI.

Materials and Methods

Contrast‐enhanced Look‐Locker MRI was performed in 35 DCM patients. Nonscarred myocardial and blood T1 values were calculated from the signal intensity values and the delay time obtained on Look‐Locker MRI. We assessed the correlation between the myocardial T1 value or myocardial T1 minus blood T1 value and cardiac function estimated using cine MRI (e.g., end‐diastolic volume: EDV, left ventricular ejection fraction: LVEF) or brain natriuretic peptide (BNP).

Results

With 1.5T MRI (n = 16), the myocardial T1 value correlated negatively with the EDV(r = −0.66) and end‐systolic volume (ESV; r = −0.68), and positively with the LVEF (r = 0.51); the myocardial T1 minus blood T1 value correlated inversely with EDV (r = −0.70), ESV (r = −0.62), and brain natriuretic peptide (BNP; r = −0.56). With 3.0T MRI (n = 17), the myocardial T1 value correlated negatively with ESV (r = −0.44), septal thickness (r = −0.60), and BNP (r = −0.51), and positively with LVEF (r = 0.61); the myocardial T1 minus blood T1 value negatively correlated with BNP (r = −0.50) and positively with LVEF (r = 0.54).

Conclusion

The nonscarred myocardial T1 value measured with either 1.5T or 3.0T contrast‐enhanced Look‐Locker MRI is significantly related to cardiac dysfunction in DCM. J. Magn. Reson. Imaging 2013;38:1395–1401. © 2013 Wiley Periodicals, Inc.
Prospects ofin ovofeeding and nutrient supplementation for poultry: the science and commercial applications—a review
Authors: Kadam Mukund M , Barekatain Mohammad R , K Bhanja Subrat , Iji Paul A
Published: July 2013

In ovosupplementation of poultry embryos was first reported several decades ago, but it is only recently that concerted research has been directed at developing the technology for this process to be routinely used by the poultry industry. Although the technology ofin ovofeeding was patented more than 10 years ago, it has not been widely adopted by the poultry industry. This review examines the early development of the enteric system of the poultry embryo; defines and distinguishes betweenin ovofeeding andin ovonutrient administration; highlights the importance of early feeding of the chick; and discusses the development ofin ovofeeding technology and its effects on hatchability, growth, gut health and immune response of chicks. The range of possible nutrients that can be administered is also explored. The limitations associated with embryo development and nutrient metabolism are highlighted, leading to the prediction of the future role ofin ovofeeding in the poultry industry. © 2013 Society of Chemical Industry
Managing Organisational Knowledge: A Case Study of a Global Energy Consulting Group
Authors: Skok Walter , Clarke Kevin , Krishnappa Sandeep
Published: July 2013

This paper describes a two‐year project to improve the management of organisational knowledge within a global energy consulting group by reviewing current practice and implementing new working practices, processes and systems.

The case study approach adopted is divided into three parts and includes the following: the review of the initial situation, the desired future aims (covering core processes of generation, storage, distribution and application of knowledge) and a comprehensive implementation strategy. The paper outlines the corresponding management of change initiative to promote a new Knowledge Management (KM) programme throughout the organisation and the introduction of new processes, staff responsibilities and roles, knowledge dissemination and sharing, intranet design using SharePoint 2010 and an engagement plan for stakeholder involvement.

The findings first confirm the classic success factors for KM projects, such as management buy‐in, stakeholder participation, comprehensive training and need for super users. Second, they highlight the problems associated with standardising business processes across disparate locations where the staff have local customs and knowledge. Finally, the case demonstrates the importance of initially considering information rather than KM issues and explicitly showing potential benefits to individuals. In this way, careful consideration of business, people and technology factors can produce gains at an individual level that can then lead to long term organisational benefits, such as faster and comprehensive proposal preparation, improved client satisfaction and more effective knowledge sharing. The results will be of practical use to organisations undertaking similar global KM initiatives. Copyright © 2013 John Wiley & Sons, Ltd.
Whose experience is measured?: A pilot study of patient satisfaction demographics in pediatric otolaryngology
Authors: Nieman Carrie L. , Benke James R. , Ishman Stacey L. , Smith David F. , Boss Emily F.
Published: July 2013

Objectives/Hypothesis

Despite a national emphasis on patient‐centered care and cultural competency, minority and low‐income children continue to experience disparities in health care quality. Patient satisfaction scores are a core quality indicator. The objective of this study was to evaluate race and insurance‐related disparities in parent participation with pediatric otolaryngology satisfaction surveys.

Study Design

Observational analysis of patient satisfaction survey respondents from a tertiary pediatric otolaryngology division.

Methods

Demographics of survey respondents (Press Ganey Medical Practice Survey©) between January and July 2012 were compared to a clinic comparison group using t test and chi‐square analyses. Multivariate logistic regression analyses were performed to assess likelihood to complete a survey based on race or insurance status.

Results

A total of 130 survey respondents were compared to 1,251 patients in the comparison group. The mean patient age for which the parent survey was completed was 5.7 years (6.1 years for the comparison group, P = 0.18); 59.2% of children were ≤5 years old. Relative to the comparison group, survey respondents were more often white (77.7% vs. 58.1%; P <0.001) and privately insured (84.6% vs. 60.8%; P <0.001). Similarly, after controlling for confounding variables, parents of children who were white (OR 1.8, 95% CI 1.13–2.78, P = 0.013) or privately insured (OR 2.9, 95% CI 1.74–4.85, P <0.001) were most likely to complete a survey.

Conclusion

Methods to evaluate satisfaction did not capture the racial or socioeconomic patient distribution within this pediatric division. These findings challenge the validity of applying patient satisfaction scores, as currently measured, to indicate health care quality. Future efforts to measure and improve patient experience should be inclusive of a culturally diverse population.

Level of Evidence

2c. Laryngoscope, 124:290–294, 2014
Kinetics of Dithiobenzoate‐Mediated Methyl Methacrylate Polymerization
Authors: Sidoruk Alana , Buback Michael , Meiser Wibke
Published: July 2013

The equilibrium constant, Keq, of the reversible addition–fragmentation chain transfer (RAFT) model system methyl methacryl dithiobenzoate (MMADB) and of methyl methacrylate (MMA) polymerization mediated by MMADB is studied via electron paramagnetic resonance (EPR) spectroscopy in the range 70 to 110 °C and at −40 °C, respectively. The measured difference in activation energy of the addition and fragmentation steps is: Ea(kad) – Ea(kfrag) ≈ −36.6 kJ mol−1. Significant amounts of “missing step” products from reaction of the cross‐termination product with a methyl methacrylyl radical are found. The fast “missing step” reaction and low Keq, due to slow kad, are responsible for rate retardation being absent in dithiobenzoate‐mediated MMA polymerization.

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Synthesis and Characterization of Ethyl Cellulose Microcapsules Containing Model Active Ingredients
Authors: Pitol‐Filho Luizildo , Kokol Vanja , Voncina Bojana
Published: July 2013

Polymers have a wide range of applications, including controlled drug release. In this paper, the methodology to produce microcapsules containing limonene and vanillin as model active ingredients is reported. Polymeric solutions composed by ethyl acetate as solvent, ethyl cellulose as the polymer and an active ingredient were prepared. The microcapsules were produced by dropping the polymeric solution on a coagulation bath, composed by water, sodium dodecyl sulfate, and acetic acid in different concentrations. The variation in concentrations was set to configurate coagulation baths with a wide range of surface tensions. According to the surface tensions, and through Scanning Electron Microscopy (SEM), different structures were observed: spongeous particles, polymeric dense rings or spherical microcapsules. The microparticles obtained had an average diameter of 30 µm. Selected structures were characterized internally by using SEM and Focused Ion Beam (FIB) in a Dual Beam Microscope. The external surface of the spherical particles was mostly dense, with observed nanopores, while micropores were distributed all along the inner structure, probably containing the active ingredient. The artifacts produced during characterization by FIB, as well the thermodynamics of the microcapsules formation are also discussed.
Amphiphilic Block Copolymer Vesicles for Active Wound Dressings: Synthesis of Model Systems and Studies of Encapsulation and Release
Authors: Haas Simon , Chen Yizhou , Fuchs Christian , Handschuh Stephan , Steuber Marc , Schönherr Holger
Published: July 2013

Polystyrene‐block‐poly(acrylic acid) (PS‐b‐PAA) diblock copolymers were synthesized via atom transfer radical polymerization (ATRP). Self‐assembly of these block copolymers into polymeric vesicles, so‐called polymersomes, was performed by addition of water to a solution of the block copolymers in tetrahydrofuran (THF). Various antimicrobial compounds and dyes were incorporated in the polymersomes and in addition to the corresponding size distributions, as determined by dynamic light scattering (DLS), the maximum attainable loading concentrations were determined. Using the release of incorporated calcein, which is a pH responsive dye, the principle of a light up probe approach for advanced in situ diagnostics was demonstrated. The release from PS‐b‐PAA vesicles via a vesicle‐to‐micelle transition was triggered by heating a vesicle suspension after addition of the plasticizer THF to 50 °C. Furthermore, a biocompatible and degradable block copolymer system, which contains degradable ester bonds in the main chain, was synthesized and investigated. In particular, poly(ethylene glycol)‐block‐polycaprolactone (PEG‐b‐PCL) copolymers were synthesized via ring‐opening polymerization (ROP). These copolymers were shown to form polymersomes as well and represent a promising family of degradable amphiphilic block copolymers for active wound dressings and related applications.
Synthesis and Characterization of Ethylene/1‐Octene Copolymer Based Ionomer Nanocomposite
Authors: Pradhan Sharmila , Scholtissek Stefanie , Ghimire Ajit , Lach Ralf , Grellmann Wolfgang , Adhikari Rameshwar
Published: July 2013

A new type of ionomeric nanocomposite based on elastomeric ethylene/1‐octene copolymer (EOC) and organophilically modified layered silicate was synthesized through sulfonation of the EOC followed by solution casting. The morphology–mechanical properties correlation of the product was studied with the help of scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy and recording microindentation measurement. The nanocomposite with uniformly distributed filler morphology could be conveniently prepared. It was found that the Martens hardness of ionomer nanocomposite comprising 5 wt.‐% layered silicate is approximately threefold of the neat elastomer.
Elevated arteriolar cerebral blood volume in prodromal Huntington's disease
Authors: Hua Jun , Unschuld Paul G. , Margolis Russell L. , van Zijl Peter C. M. , Ross Christopher A.
Published: July 2013

Background

Neurovascular alterations have been implicated in the pathophysiology of Huntington's disease (HD). Because arterioles are most responsive to metabolic alterations, arteriolar cerebral blood volume (CBVa) is an important indicator of cerebrovascular regulation. The objective of this pilot study was to investigate potential neurovascular (CBVa) abnormality in prodromal‐HD patients and compare it with the widely used imaging marker: brain atrophy.

Methods

CBVa and brain volumes were measured with ultra‐high‐field (7.0‐Telsa) magnetic resonance imaging in seven prodromal‐HD patients and nine age‐matched controls.

Results

Cortical CBVa was elevated significantly in prodromal‐HD patients compared with controls (relative difference, 38.5%; effect size, 1.48). Significant correlations were found between CBVa in the frontal cortex and genetic measures. By contrast, no significant brain atrophy was detected in the prodromal‐HD patients.

Conclusions

CBVa may be abnormal in prodromal‐HD, even before substantial brain atrophy occurs. Further investigation with a larger cohort and longitudinal follow‐up is merited to determine whether CBVa could be used as a potential biomarker for clinical trials. © 2013 Movement Disorder Society
Preoperative MR angiography for free fibula osteocutaneous flap transfer
Authors: Akashi Masaya , Nomura Tadashi , Sakakibara Shunsuke , Sakakibara Akiko , Hashikawa Kazunobu
Published: July 2013

Introduction: Magnetic resonance angiography (MRA) is currently considered the most useful test to evaluate the vascular anatomy of the lower leg prior to free fibula osteocutaneous flap transfer. This study aimed to confirm the validity of preoperative MRA. Methods: In 19 patients underwent free fibula osteocutaneous flap transfer for maxillary and mandibular reconstruction, the MRA and intraoperative findings and the postoperative complications were retrospectively analyzed. The location and number of distal septocutaneous perforators (dSCPs) that were preoperatively identified and harvested with flaps were documented. Results: Preoperative MRA detected dSCPs with 100 % sensitivity. MRA findings also revealed the diversity of vascular structures, such as the tibio‐peroneal bifurcation location and the anatomical relationship between the peroneal vessels and the fibula. No patients suffered postoperative ischemic complications in the donor leg. The total flap survival rate was 95 %. Conclusions: Preoperative MRA effectively excluded large vessel anomalies and peripheral vascular disease, and precisely identified the septocutaneous perforators. Additionally, preoperative MRA contributed to a safer fibular osteotomy by predicting the anatomical relationship between the peroneal vessels and the fibula. © 2013 Wiley Periodicals, Inc. Microsurgery 33:454–459, 2013.
Development of Cyclic Propagation Kinetics for Modeling the Nitroxide‐mediated Radical Copolymerization of Styrene–Divinylbenzene
Authors: Aguiar Leandro G. , Gonçalves Miguel A. D. , Pinto Virgínia D. , Dias Rolando C. S. , Costa Mário Rui P. F. N. , Giudici Reinaldo
Published: July 2013

A kinetic model including the cyclic propagation (cyclization) is proposed for the nitroxide‐mediated radical copolymerization of styrene–divinylbenzene. The method involves a balance of sequences of units, which connect a radical center and a pendant double bond present in the same polymer chain. The rate constant for cyclization was considered a function of the sequence length. Good agreement between the model predictions and experimental data for solution and suspension controlled copolymerizations was found. The rate constant of cyclization for the smallest ring (3 monomeric units) was estimated to be 700 s−1 at 90 °C, and the activation energy was estimated to be 32 500 cal mol−1.
Selective damping method for the weak‐Arlequin coupling of molecular dynamics and finite element method
Authors: Shan Wenzhe , Nackenhorst Udo
Published: July 2013

An artificial damping force is introduced in the weak coupling between the molecular dynamics (MD) and finite element (FE) models, to reduce the reflection of the high‐frequency motion that cannot be transmitted from the MD domain to the FE domain. We take advantage of the orthogonal property of the decomposed velocity in the weak coupling method and apply the damping force only to the high‐frequency part, therefore minimizing its effect on the low‐frequency part, which can be transmitted into the FE domain. The effectiveness of the damping method will be demonstrated by 1D numerical examples with linear force field applied to the atomistic model. In addition, we emphasize the importance of using the Arlequin energy interpolation, which is usually ignored in the weak coupling literature. Non‐uniform rational basis spline functions have been used to interpolate the MD data for the weak coupling method, and the influence of changing the number and order of basis functions on the interpolation accuracy has been investigated numerically. For this work, we restrict our discussion to mechanical problems only, involving only mechanical energy terms (e.g., strain potential and kinetic energy). Copyright © 2013 John Wiley & Sons, Ltd.
The impact of maternal obesity and gestational weight gain on early and mid‐pregnancy lipid profiles
Authors: Scifres Christina M. , Catov Janet M. , Simhan Hyagriv N.
Published: July 2013

Objective

The impact of maternal overweight/obesity and excessive weight gain on maternal serum lipids in the first and second trimester of pregnancy was evaluated.

Methods

Prospective data were collected for 225 women. Maternal serum lipids and fatty acids were measured at <13 weeks and between 24 and 28 weeks. Analyses were stratified by normal weight versus overweight/obese status and excessive versus nonexcessive weight gain.

Results

Overweight/obese women had higher baseline cholesterol (161.3 ± 29.6 vs. 149.4 ± 26.8 mg/dl, P < 0.01), low‐density lipoprotein LDL (80.0 ± 19.9 vs. 72.9 ± 18.8 mg/dl, P < 0.01), and triglycerides (81.7 ± 47.2 vs. 69.7 ± 40.3 mg/dl, P = 0.05) when compared to normal weight women, whereas high‐density lipoprotein (43.6 ± 10.4 vs. 47.6 ± 11.5 mg/dl, P < 0.01) was lower. However, cholesterol and LDL increased at a higher weekly rate in normal weight women, resulting in higher total cholesterol in normal weight women (184.1 ± 28.1 vs. 176.0 ± 32.1 mg/dl, P = 0.05) at 24–28 weeks. The rate of change in lipid profiles in either group was not affected by excessive weight gain. Overweight/obese women had higher levels of arachidonic acid at both time points.

Conclusions

Overweight/obese women have significantly more atherogenic lipid profiles than normal weight women during the period of early pregnancy, delineating one physiologic pathway between that could explain differences in pregnancy outcomes normal weight and overweight/obese women.
Synthesis of the Tolerance‐Inducing Oligosaccharide Lacto‐N‐Fucopentaose III Bearing an Activated Linker
Authors: Zhang Junfeng , Zou Lu , Lowary Todd L.
Published: July 2013

A concise synthetic route to an immunomodulatory pentasaccharide, lacto‐N‐fucopentaose III (1) and its corresponding human serum albumin conjugate, is described. Key transformations of the strategy include two highly regio‐ and stereoselective glycosylations for the construction of disaccharide 10 and pentasaccharide 12, a Birch reduction for deprotection of benzyl ethers, and a UV‐promoted radical addition of a thiol to an alkene for modification of the aglycone.
Using the Implicit Association Test to Assess Risk Propensity Self–Concept: Analysis of Its Predictive Validity on A Risk–Taking Behaviour in A Natural Setting
Authors: Horcajo Javier , Rubio Víctor J. , Aguado David , Hernández José Manuel , Márquez M. Oliva
Published: July 2013

The present work analyses the predictive validity of measures provided by several available self–report and indirect measurement instruments to assess risk propensity (RP) and proposes a measurement instrument using the Implicit Association Test: the IAT of Risk Propensity Self–Concept (IAT–RPSC), an adaptation of the prior IAT–RP of Dislich et al. Study 1 analysed the relationship between IAT–RPSC scores and several RP self–report measures. Participants’ risk–taking behaviour in a natural setting was also assessed, analyzing the predictive validity of the IAT–RPSC scores on risk–taking behaviour compared with the self–report measures. Study 2 analysed the predictive validity of the IAT–RPSC scores in comparison with other indirect measures. Results of these studies showed that the IAT–RPSC scores exhibited good reliability and were positively correlated to several self–report and indirect measures, providing evidence for convergent validity. Most importantly, the IAT–RPSC scores predicted risk–taking behaviour in a natural setting with real consequences above and beyond all other self–report and indirect measures analysed. Copyright © 2013 European Association of Personality Psychology
Quick to Act, Quick to Forget: The Link between Impulsiveness and Prospective Memory
Authors: Cuttler Carrie , Relkov Tonia , Taylor Steven
Published: July 2013

Several traits of impulsiveness (e.g. lack of planning and perseverance, difficulty focusing attention) seem intimately connected to the skills required for successful prospective memory performance. This is the first study to examine whether the various inter–correlated dimensions of impulsiveness are related to problems with prospective memory. Undergraduate students (N = 184) completed the Barratt Impulsiveness Scale 11, the Prospective Memory Questionnaire, the Prospective and Retrospective Memory Questionnaire, and two objective prospective memory tests. Results revealed consistent correlations between the various dimensions of impulsiveness (attentional, motor, non–planning) and self–reported problems with prospective memory. Subsequent regression analyses indicated that attentional impulsiveness is a unique predictor of self–reported problems with internally cued prospective memory, and non–planning impulsiveness is a unique predictor of self–reported problems with episodic and overall prospective memory. Similarly, findings from the objective prospective tests showed that non–planning impulsiveness was related to worse performance on the two prospective memory tests. Whereas non–planning impulsiveness was also related to using fewer prospective memory–aiding strategies, mediation analyses showed that use of these strategies does not account for any of the detected relationships. Because the findings suggest that a failure to plan does not underlie the detected effects, other potential explanations for the relationships are discussed. Copyright © 2013 European Association of Personality Psychology
Calculated stabilities and structures for carbocations and singlet carbenes bearing electron‐withdrawing groups
Authors: Gronert Scott , Keeffe James R.
Published: July 2013

Carbocations and carbenes, as electron‐deficient species, require electron donation from the remainder of the molecule to the carbon center by whatever means available. Classical interactions include resonance, polar and polarizability effects, but neighboring group participation of several sorts can also serve as stabilizing factors. Simple carbocations with directly attached electron‐withdrawing groups (EWGs), that is, EWG–CH2+ ions, comprise one group by which these interactions may be probed. This article provides computational evidence at the MP2/6‐311 + G** level for variable but significant stabilizing interactions between the carbocation center and common EWGs, many via bridging (partial or symmetrical), neighboring group participation, homoconjugation or π interactions. Bridging from atoms possessing nonbonding electron pairs is a common motif. Removal of bridging by application of geometric constraints nullifies bridging stabilization, but does not eliminate the possibility of other stabilizing interactions, for example polar, polarizability and π donation from the EWG. The potential for π donation from strong EWGs has not been widely appreciated in the past. A carbocation stabilization enthalpy, CSE+, is defined as the enthalpy of the isodesmic reaction CH3+ + R–H → CH4 + R+. Comparisons are made with singlet carbenes bearing EWGs for which many structural features are similar. Copyright © 2013 John Wiley & Sons, Ltd.
Probabilistic quantitative precipitation forecasting using Ensemble Model Output Statistics
Authors: Scheuerer M.
Published: July 2013

Statistical post‐processing of dynamical forecast ensembles is an essential component of weather forecasting. In this article, we present a post‐processing method which generates full predictive probability distributions for precipitation accumulations based on ensemble model output statistics (EMOS).

We model precipitation amounts by a generalized extreme value distribution which is left‐censored at zero. This distribution permits modelling precipitation on the original scale without prior transformation of the data. A closed form expression for its continuous ranked probability score can be derived and permits computationally efficient model fitting. We discuss an extension of our approach which incorporates further statistics characterizing the spatial variability of precipitation amounts in the vicinity of the location of interest.

The proposed EMOS method is applied to daily 18 h forecasts of 6 h accumulated precipitation over Germany in 2011 using the COSMO‐DE ensemble prediction system operated by the German Meteorological Service. It yields calibrated and sharp predictive distributions and compares favourably with extended logistic regression and Bayesian model averaging which are state‐of‐the‐art approaches for precipitation post‐processing. The incorporation of neighbourhood information further improves predictive performance and turns out to be a useful strategy to account for displacement errors of the dynamical forecasts in a probabilistic forecasting framework.
Variance estimation for Brier Score decomposition
Authors: Siegert Stefan
Published: July 2013

The Brier Score is a widely used criterion to assess the quality of probabilistic predictions of binary events. The expectation value of the Brier Score can be decomposed into the sum of three components called reliability, resolution and uncertainty, which characterize different forecast attributes. Given a dataset of forecast probabilities and corresponding binary verifications, these three components can be estimated empirically. Here, propagation of uncertainty is used to derive expressions that approximate the sampling variances of the estimated components. Variance estimates are provided for both the traditional estimators, as well as for refined estimators that include a bias correction. Applications of the derived variance estimates to artificial data illustrate their validity and application to a meteorological prediction problem illustrates a possible usage case. The observed increase of variance of the bias‐corrected estimators is discussed.
Dynamics of Cu monomer, dimer and trimer on Ag (110) (1 × 2) missing‐row reconstructed surface
Authors: Sbiaai Khalid , Boughaleb Yahia , Mazroui M'hammed , Kara Abdelkader
Published: July 2013

The authors aimed to investigate the diffusion of Cu monomer, dimer and trimer on Ag (110) (1×2) missing‐row surface. This problem is addressed through molecular dynamic simulation based on semi‐empirical many‐body potential, derived from the embedded atom method. Within this approach, we have identified and calculated the activation energy of each microscopic mechanism. Thus, for Cu monomer, the diffusion process occurs essentially by simple hopping between nearest‐neighbor sites. While for the Cu dimer, three processes have been identified such as dissociation–reassociation (DR), concerted jump (CJ) and leapfrog mechanisms (LF) with a slight predominance of DR process and a dual competition between CJ and LF processes. But, in the case of small one‐dimensional cluster such as trimer on (110)(1×2) missing‐row reconstructed surface, the main diffusion mechanism is the LF process. These results shed light on the diffusion processes on missing‐row reconstructed surfaces, especially for heterogeneous systems. Copyright © 2013 John Wiley & Sons, Ltd.
Functional endothelial progenitor cells selectively recruit neurovascular protective monocyte-derived F4/80+/Ly6c+ macrophages in a mouse model of retinal degeneration
Authors: Fukuda Shinichi , Nagano Masumi , Yamashita Toshiharu , Kimura Kenichi , Tsuboi Ikki , Salazar Georgina , Ueno Shinji , Kondo Mineo , Kunath Tilo , Oshika Tetsuro , Ohneda Osamu
Published: July 2013

Retinitis pigmentosa is a group of inherited eye disorders that result in profound vision loss with characteristic retinal neuronal degeneration and vasculature attenuation. In a mouse model of retinitis pigmentosa, endothelial progenitor cells (EPC) from bone marrow rescued the vasculature and photoreceptors. However, the mechanisms and cell types underlying these protective effects were uncertain. We divided EPC, which contribute to angiogenesis, into two subpopulations based on their aldehyde dehydrogenase (ALDH) activity and observed that EPC with low ALDH activity (Alde-Low) had greater neuroprotection and vasoprotection capabilities after injection into the eyes of an rd1 mouse model of retinitis pigmentosa compared with EPC with high ALDH activity (Alde-High). Of note, Alde-Low EPC selectively recruited F4/80+/Ly6c+ monocyte-derived macrophages from bone marrow into retina through CCL2 secretion. In addition, the mRNA levels of CCR2, the neurotrophic factors TGF-β1 and IGF-1, and the anti-inflammatory mediator interleukin-10 were higher in migrated F4/80+/Ly6c+ monocyte-derived macrophages as compared with F4/80+/Ly6c− resident retinal microglial cells. These results suggest a novel therapeutic approach using EPC to recruit neuroprotective macrophages that delay the progression of neural degenerative disease.
Biofuels: economic, environmental and social benefits and costs for developing countries in Asia
Authors: Gheewala Shabbir H. , Damen Beau , Shi Xunpeng
Published: July 2013

Biofuels are being supported by many governments for a range of perceived benefits including improved domestic energy security, reduced greenhouse gas (GHG) emissions when compared with fossil‐fuel counterparts, and economic development and employment generation, particularly in rural areas. Life‐cycle, cost‐benefit, and systems analyses, however, indicate that the expansion of biofuels can have complex effects on, and interactions with, land use and food and fuel prices. This article reviews the economic, environmental, and social benefits and costs of biofuels using experiences from developing countries in Asia. The review reveals the following: (1) biofuels are generally not economically competitive with fossil fuels and government support, though prevailing, is costly and questionable. (2) Although biofuels are generally viewed to be a threat to food security, if properly managed, their development could lead to improved productivity in the agriculture sector over the long term with benefits for rural livelihoods and food security. (3) Even though reducing GHG emissions is a key driver for the development of biofuels, effects in terms of soil quality, biodiversity, and water quality must also be assessed; the environmental benefits of biofuels are debatable and depend on a range of fuel‐specific factors, management, and agricultural practices. On the basis of this assessment a range of strategies are suggested to further improve the sustainability of biofuels in Asia. WIREs Clim Change 2013, 4:497–511. doi: 10.1002/wcc.241

This article is categorized under:

The Carbon Economy and Climate Mitigation > Benefits of Mitigation

Climate and Development > Decoupling Emissions from Development
Developing Measures of Community‐Relevant Outcomes for Violence Prevention Programs: A Community‐Based Participatory Research Approach to Measurement
Authors: Hausman Alice J. , Baker Courtney N. , Komaroff Eugene , Thomas Nicole , Guerra Terry , Hohl Bernadette C. , Leff Stephen S.
Published: July 2013

Community‐Based Participatory Research is a research paradigm that encourages community participation in designing and implementing evaluation research, though the actual outcome measures usually reflect the “external” academic researchers’ view of program effect and the policy‐makers’ needs for decision‐making. This paper describes a replicable process by which existing standardized psychometric scales commonly used in youth‐related intervention programs were modified to measure indicators of program success defined by community partners. This study utilizes a secondary analysis of data gathered in the context of a community‐based youth violence prevention program. Data were retooled into new measures developed using items from the Alabama Parenting Questionnaire, the Hare Area Specific Self‐Esteem Scale, and the Youth Asset Survey. These measures evaluated two community‐defined outcome indicators, “More Parental Involvement” and “Showing Kids Love.” Results showed that existing scale items can be re‐organized to create measures of community‐defined outcomes that are psychometrically reliable and valid. Results also show that the community definitions of parent or parenting caregivers exemplified by the two indicators are similar to how these constructs have been defined in previous research, but they are not synonymous. There are nuanced differences that are important and worthy of better understanding, in part through better measurement.
Comments on a Method for Estimating Cloud Point and Cold Filter Plugging Point of Microalgal Oil Fatty Acid Methyl Esters
Authors: Iyer Ramasubramania
Published: July 2013

Cloud points (CPs) of five vegetable oil fatty acid methyl esters (FAME) and three biodiesel mixtures estimated by a thermodynamic equation were compared to measured CPs. The results indicate that estimated CP of peanut oil FAME are similar to measured CP and for three biodiesel mixtures a minimum total saturated FAME (SFAME) concentration is required for measured CPs to be closer to estimated CPs. These comparisons provide the basis for comments on using this method for estimating CPs of 22 test data of microalgae FAME. Cold filter plugging points (CFPPs) calculated by equation CFPP = 1.0191 × CP − 2.9 with CPs verified from the thermodynamic equation was found to be identical to CFPPs reported in literature for 22 test data of microalgae FAME. Therefore these CPs were inserted in equation CFPP = CP −4.5 for another set of CFPPs. Plots of CFPPs versus percent SFAME of the 22 test data of microalgae FAME (>12 %) for these two equations indicates that CFPP is controlled by 85 % of SFAME. Calculated CFPPs of vegetable oil FAME and biodiesel mixtures using both equations for estimated and measured CPs is discussed. Low concentrations of long chain saturated FAME impacting the estimation of CPs of vegetable oil FAME is used as a rationale to discuss the role of unidentified other species (OS) in estimation of CPs of microalgae FAME.
A link between two tumorigenic proteins, CD44 and p21WAF1: CD44 increases phorbol ester‐induced expression of p21WAF1 by stabilizing its mRNA and extending protein half‐life
Authors: Lindner Christina , Urbánek Pavel , Pavelka Birgit , Hartmann Monika , Herrlich Peter
Published: July 2013

The cell surface glycoprotein CD44 enhances phorbol‐12‐myristate 13‐acetate (TPA)‐induced expression of p21WAF1 by stabilizing its mRNA and enhancing the protein's half‐life in several cell lines. Only the plasma membrane‐anchored cytoplasmic tail of CD44 and its interacting ezrin, radixin, moesin (ERM) proteins are required for this effect. A mitogen activated kinase (MEK) inhibitor abolishes the action of CD44 on p21. Down‐regulation of p21 dramatically decreased anchorage‐independence of a cancer cell line, whereas CD44 expression in this background could partially rescue the phenotype.
A new regulatory principle for in vivo biochemistry: Pleiotropic low affinity regulation by the adenine nucleotides – Illustrated for the glycolytic enzymes of Saccharomyces cerevisiae
Authors: Mensonides Femke I.C. , Bakker Barbara M. , Cremazy Frederic , Messiha Hanan L. , Mendes Pedro , Boogerd Fred C. , Westerhoff Hans V.
Published: July 2013

We test this hypothesis in terms of the effect that ATP, ADP, and AMP might have on the major free‐energy delivering pathway of the yeast Saccharomyces cerevisiae. Assaying cell‐free extracts, we collected a comprehensive set of quantitative kinetic data concerning the enzymes of the glycolytic and the ethanol fermentation pathways. We determined systematically the extent to which the enzyme activities depend on the concentrations of the adenine nucleotides. We found that the effects of the adenine nucleotides on enzymes catalysing reactions in which they are not directly involved as substrate or product, are substantial. This includes effects on the Michaelis–Menten constants, adding new perspective on these, 100 years after their introduction.
Obstetric interventions for women with type 1 or type 2 diabetes
Authors: Cundy Tim , Morgan Joanna , O'Beirne Claire , Gamble Greg , Budden Astrid , Ivanova Valeria , Wallace Mairi
Published: July 2013

Objective

To determine whether differences exist in the rates of obstetric intervention between women with type 1 diabetes and those with type 2 diabetes, and whether there has been any change in cesarean rates over time, paralleling that seen in the general obstetric population.

Methods

Data were examined from a prospectively collected series on the outcomes of 1030 deliveries (382 by women with type 1 diabetes, 648 by women with type 2 diabetes) from 1988 to 2008.

Results

There was a secular trend to increasing maternal age (type 1, P < 0.003; type 2, P < 0.03). Intervention rates (induction of labor or elective cesarean) did not differ between type 1 (88%) and type 2 (85%) diabetes. The overall cesarean rate was 52%–55% with no secular trend. Poorer glycemic control in early pregnancy and primiparity were associated with primary cesarean in both groups. In women with type 1 diabetes, greater maternal obesity and retinopathy were also associated with primary cesarean.

Conclusion

Intervention rates are high in pregnancies among women with type 1 diabetes and those with type 2 diabetes but they have not changed significantly. Secular trends toward increasing maternal age and obesity suggest that intervention rates are unlikely to decrease in the near future.