bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Nanostructured Nb2O5 Catalysts
Authors: Zhao Yun , Zhou Xiwen , Ye Lin , Tsang Shik Chi Edman
Published: November 2012

Review: 58 refs.
ChemInform Abstract: Anodic Selective Functionalization of Cyclic Amine Derivatives
Authors: Onomura Osamu
Published: November 2012

Review: 105 refs.
ChemInform Abstract: Development of Iridium‐Catalyzed Asymmetric Hydrogenation: New Catalysts, New Substrate Scope
Authors: Cadu Alban , Andersson Pher G.
Published: November 2012

Review: ca. 70 refs.
ChemInform Abstract: Designer Chiral Phase‐Transfer Catalysts for Green Sustainable Chemistry
Authors: Maruoka Keiji
Published: November 2012

Review: 36 refs.
ChemInform Abstract: Synthetic Approaches and Pharmacological Activity of 1,3,4‐Oxadiazoles. A Review of the Literature from 2000‐2012
Authors: Soares de Oliveira Cledualdo , Lira Bruno Freitas , Barbosa‐Filho Jose Maria , Lorenzo Jorge Goncalo Fernandez , Filgueiras de Athayde‐Filho Petronio
Published: November 2012

Review: 165 refs.
ChemInform Abstract: Protein Tango: The Toolbox to Capture Interacting Partners
Authors: Rutkowska Anna , Schultz Carsten
Published: November 2012

Review: ca. 150 refs.
Eu2+ & Mn2+‐Coactivated Ba3Gd(PO4)3 Orange‐Yellow‐Emitting Phosphor with Tunable Color Tone for UV‐Excited White LEDs
Authors: Guo Ning , Lü Wei , Jia Yongchao , Lv Wenzhen , Zhao Qi , You Hongpeng
Published: November 2012

A novel orange‐yellow‐emitting Ba3Gd(PO4)3:x Eu2+,y Mn2+ phosphor is prepared by high‐temperature solid‐state reaction. The crystal structure of Ba3Gd(PO4)3:0.005 Eu2+,0.04 Mn2+ is determined by Rietveld refinement analysis on powder X‐ray diffraction data, which shows that the cations are disordered on a single crystallographic site and the oxygen atoms are distributed over two partially occupied sites. The photoluminescence excitation spectra show that the developed phosphor has an efficient broad absorption band ranging from 230 to 420 nm, perfectly matching the characteristic emission of UV‐light emitting diode (LED) chips. The emission spectra show that the obtained phosphors possess tunable color emissions from yellowish‐green through yellow and ultimately to reddish‐orange by simply adjusting the Mn2+ content (y) in Ba3Gd(PO4)3:0.005 Eu2+,y Mn2+ host. The tunable color emissions origin from the change in intensity between the 4f–5d transitions in the Eu2+ ions and the 4T1‐6A1 transitions of the Mn2+ ions through the energy transfer from the Eu2+ to the Mn2+ ions. In addition, the mechanism of the energy transfer between the Eu2+ and Mn2+ ions are also studied in terms of the Inokuti–Hirayama theoretical model. The present results indicate that this novel orange‐yellow‐emitting phosphor can be used as a potential candidate for the application in white LEDs.
Intramolecular Cascade Hydroarylation/Cycloisomerization Strategy for the Synthesis of Polycyclic Aromatic and Heteroaromatic Systems
Authors: Storch Jan , Bernard Martin , Sýkora Jan , Karban Jindřich , Čermák Jan
Published: November 2012

A new PtCl2/PtCl4‐catalyzed hydroarylation/cycloisomerization cascade reaction leading to the formation of two aromatic or heteroaromatic rings in one step is reported. The strategy developed is exemplified by the synthesis of the 5,6‐dihydrobenzo[c]phenanthrene and 6H‐naphtho[2,1‐c]chromene skeletons. Attempts to prepare [8]helicene‐like molecules are also discussed.
pH and Temperature Determine Performance of Oxygen Reducing Biocathodes
Authors: Strik David P. B. T. B. , Picot Matthieu , Buisman Cees J. N. , Barrière Frédéric
Published: November 2012

In this paper we investigate the performance of oxygen reducing biocathodes for microbial fuel cells in relation to temperature and pH. Lower pH does likely improve biocatalytic activity and/or proton availability, and results in higher current. Lower temperature does reduce biocatalytic activity and does not reduce possible oxygen mass transfer limitations. The cathode resistance was in the same order of magnitude at pH 5 to 7 which shows that MFC energy recovery can be higher at lower pH. Overall, these results show that oxygen reducing biocathodes are robust at 660 mA per m2 at +0.15 V vs. Ag/AgCl, pH 5 and 31 °C.
Reservoir‐based dielectrophoresis for microfluidic particle separation by charge
Authors: Patel Saurin , Qian Shizhi , Xuan Xiangchun
Published: November 2012

The separation of particles from a complex mixture is important to a wide range of applications in industry, biology, medicine etc. This work demonstrates a microfluidic approach to separate similar‐sized fluorescent and nonfluorescent particles based upon the difference in their surface charges inside a reservoir. Such a separation exploits the reservoir‐based dielectrophoresis, which is induced by the inherent electric field gradient formed at the reservoir–microchannel junction, to isolate the trapped fluorescent particles within the reservoir from the streaming nonfluorescent particles. The effects of the DC field magnitude (or equivalently the electrokinetic flow magnitude) and the AC field frequency of DC‐biased AC electric fields are investigated on particle separation. A numerical model is also developed to simulate the electrokinetic transport behaviors of the two types of particles. This demonstrated reservoir‐based dielectrophoresis particle sorter can operate in parallel to increase the flow throughput. It is suitable for integration with other functional parts into lab‐on‐a‐chip devices for diverse particle handling.
Synthesis of Functionalized Glutamine‐ and Asparagine‐Type Peptoids – Scope and Limitations
Authors: Cardenal Carmen , Vollrath Sidonie B. L. , Schepers Ute , Bräse Stefan
Published: November 2012

N‐Alkylated glycine oligomers (‘peptoids’) can serve as potent peptidomimetic systems. Installing different functional groups can often be a challenge, and minimizes yields and purities. Here, we describe the synthesis of different amide‐containing submonomers which were obtained as free bases, as well as their incorporation into peptoids. By using the free amines, the coupling results on solid support could be improved, and various functionalized peptoids were prepared. Additionally, an interesting dimerization side reaction leading to cross‐linked peptoids was observed during synthesis.
Laminar Silk Scaffolds for Aligned Tissue Fabrication
Authors: Mandal Biman B. , Gil Eun Seok , Panilaitis Bruce , Kaplan David L.
Published: November 2012

3D‐biomaterial scaffolds with aligned architecture are of vital importance in tissue regeneration. A generic method is demonstrated to produce aligned biomaterial scaffolds using the physics of directional ice freezing. Homogeneously aligned 3D silk scaffolds with high porosity and alignment are prepared. The method can be adapted to a wide range of polymers and is devoid of any chemical reactions, thus avoiding potential complications associated with by‐products. Mechanical properties and cellular responses with chondrocytes and bone‐marrow‐derived hMSCs are studied, assessing survival, proliferation, and differentiation. In vivo tests suggest biocompatibility of the matrices for future tissue engineering applications, specifically in areas where high cellular alignment is needed.

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Multifunctional Non‐Viral Delivery Systems Based on Conjugated Polymers
Authors: Yang Gaomai , Lv Fengting , Wang Bing , Liu Libing , Yang Qiong , Wang Shu
Published: November 2012

Multifunctional nanomaterials with simultaneous therapeutic and imaging functions explore new strategies for the treatment of various diseases. Conjugated polymers (CPs) are considered as novel candidates to serve as multifunctional delivery systems due to their high fluorescence quantum yield, good photostability, and low cytotoxicity. Highly sensitive sensing and imaging properties of CPs are well reviewed, while the applications of CPs as delivery systems are rarely covered. This feature article mainly focuses on CP‐based multifunctional non‐viral delivery systems for drug, protein, gene, and cell delivery. Promising directions for the further development of CP‐based delivery systems are also discussed.

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Syndiotactic Polystyrene Films with Different Uniplanar Orientations: Additional Information on Crystal Phase Transitions
Authors: Rizzo Paola , Albunia Alexandra R. , Guerra Gaetano
Published: November 2012

Syndiotactic polystyrene δ form films, exhibiting a//c// and a⟂c// uniplanar orientations and subjected to annealing procedures in the temperature range of 60–130 °C, have been thoroughly characterized by X‐ray diffraction. The reported results indicate that the gradual irreversible transformation from the nanoporous δ phase toward the dense γ phase occurs with a continuous transformation of the 010 and $ \bar 210 $ reflections of the δ form into the 020 and 200 reflections of the γ form, respectively. This analysis allows ruling out of the occurrence of a new reflection typical of an intermediate phase, as suggested by X‐ray diffraction measurements on unoriented or axially oriented samples.
Highly Filled Polystyrene/Laponite Hybrid Nanoparticles Prepared Using the Ad‐miniemulsion Polymerisation Technique
Authors: Zengeni Eddson , Hartmann Patrice C. , Pasch Harald
Published: November 2012

The preparation of highly filled polystyrene/Laponite (PS/Lap) hybrid nanoparticles by the ad‐miniemulsion polymerisation technique, using conventional free‐radical polymerisation, is described. Laponite (Lap) is first modified with a polymerisable cationic surfactant. Then, using a second surfactant dispersions are prepared under sonication. A stable hybrid miniemulsion is obtained after mixing and co‐sonicating both miniemulsions. The polymerisation is conducted using an oil‐soluble initiator to obtain hybrid nanoparticles. PS/Lap hybrid nanoparticles are effectively prepared with clay contents as high as 50 wt%. TEM reveals that the highly filled hybrid latexes (≥30 wt%) exhibit encapsulated morphology with homogeneously distributed clay platelets.
Simultaneous in vivo pH and temperature mapping using a PARACEST‐MRI contrast agent
Authors: McVicar Nevin , Li Alex X. , Suchý Mojmír , Hudson Robert H. E. , Menon Ravi S. , Bartha Robert
Published: November 2012

Altered tissue temperature and/or pH is a common feature in pathological conditions, where metabolic demand exceeds oxygen supply such as in tumors and following stroke. Therefore, in vivo tissue temperature and pH may become valuable biomarkers for disease detection and the monitoring of disease progression or treatment response in conditions with altered metabolic demand. In this study, pH is measured using the amide protons of a thulium (Tm3+) complex with a DOTAM‐Glycine‐Lysine (ligand: Tm3+‐DOTAM‐Gly‐Lys). The pH was uniquely determined from the linewidth of the asymmetry curve of the chemical exchange saturation transfer spectrum, independent of contrast agent concentration, or temperature for a given saturation pulse. pH maps with an inter‐pixel standard deviation of less than 0.1 pH units were obtained in 10 mM Tm3+‐DOTAM‐Gly‐Lys solutions with pH ranging from 6.0 to 8.0 pH units at 37°C. Temperature maps were simultaneously obtained using the chemical shift of the chemical exchange saturation transfer peak. Temperature and pH maps are demonstrated in the mouse leg (N = 3), where the mean and standard deviation for pH was 7.2 ± 0.2 pH unit and temperature was 37.4 ± 0.5°C. Magn Reson Med, 70:1016–1025, 2013. © 2012 Wiley Periodicals, Inc.
Functional diffusion‐weighted magnetic resonance spectroscopy of the human primary visual cortex at 7 T
Authors: Branzoli Francesca , Techawiboonwong Aranee , Kan Hermien , Webb Andrew , Ronen Itamar
Published: November 2012

Purpose:

Microstructural and metabolic changes directly related to neuronal activation have been investigated using functional diffusion‐weighted spectroscopy.

Methods:

The volume of interest was positioned in the primary visual cortex. A time series of alternating diffusion‐ and non‐diffusion‐weighted 1H spectra was acquired at 7 T employing stimulated echo acquisition mode sequence and a long diffusion time (Δ = 245 ms). Time‐resolved series of metabolite apparent diffusion coefficient values were derived.

Results:

Significant increases in apparent diffusion coefficient of 3.3 ± 1.4% (p = 0.05) and 3.9 ± 0.9% (p = 0.002) for total n‐acetyl aspartate and total creatine, respectively, and 8.1 ± 2.5% (p = 0.03) for total choline were observed in response to visual stimulation.

Conclusion:

The increase in apparent diffusion coefficient for these metabolites is a potential indication for microstructural changes in neurons during neural activation and/or for an increase in the energy‐dependent cytoplasmic streaming associated with enhanced metabolism during visual stimulation. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Cofilin, a hypoxia‐regulated protein in murine lungs identified by 2DE: Role of the cytoskeletal protein cofilin in pulmonary hypertension
Authors: Veith Christine , Schmitt Sigrid , Veit Florian , Dahal Bhola Kumar , Wilhelm Jochen , Klepetko Walter , Marta Gabriel , Seeger Werner , Schermuly Ralph Theo , Grimminger Friedrich , Ghofrani Hossein A. , Fink Ludger , Weissmann Norbert , Kwapiszewska Grazyna
Published: November 2012

Chronic alveolar hypoxia induces vascular remodeling processes in the lung resulting in pulmonary hypertension (PH). However, the mechanisms underlying pulmonary remodeling processes are not fully resolved yet. To investigate functional changes occurring during hypoxia exposure we applied 2DE to compare protein expression in lungs from mice subjected to 3 h of alveolar hypoxia and those kept under normoxic conditions. Already after this short‐time period several proteins were significantly regulated. Subsequent analysis by MALDI‐MS identified cofilin as one of the most prominently upregulated proteins. The regulation was confirmed by western blotting and its cellular localization was determined by immunohisto‐ and immunocytochemistry. Interestingly, enhanced cofilin serine 3 phosphorylation was observed after short‐term and after chronic hypoxia‐induced PH in mice, in pulmonary arterial smooth muscle cells (PASMC) from monocrotaline‐induced PH in rats, in lungs of idiopathic pulmonary arterial hypertension patients and in hypoxic or platelet‐derived growth factor BB‐treated human PASMC. Furthermore, elevated cofilin phosphorylation was attenuated by curative treatment of monocrotaline‐induced PH in rats and hypoxia‐induced PH in mice with the PDGF‐BB receptor antagonist imatinib. In conclusion, short‐term hypoxic exposure induced prominent changes in lung protein regulation. These very early changes allowed us to identify potential triggers of PH. Thus, respective 2DE analysis can lead to the identification of new target proteins for the possible treatment of PH.
Simultaneous dual end‐functionalization of peg via the passerini three‐component reaction for the synthesis of ABC miktoarm terpolymers
Authors: Li Lei , Kan Xiao‐Wei , Deng Xin‐Xing , Song Cheng‐Cheng , Du Fu‐Sheng , Li Zi‐Chen
Published: November 2012

In this article, we demonstrate the Passerini three‐component reaction as a simple, effective method for the synthesis of polymers with double functional end groups, which are key precursors for the preparation of ABC miktoarm terpolymers. Thus, via the one‐step Passerini reaction of monomethoxy poly(ethylene glycol)–propionaldehyde (PEG‐CHO) with 2‐bromo‐2‐methylpropionic acid and propargyl isocyanoacetamide, the PEG chain end was simultaneously functionalized with one atom transfer radical polymerization (ATRP) initiating site and one alkynyl group. The resulting PEG(‐alkynyl)‐Br was then used for the synthesis of three types of miktoarm ABC terpolymers via two approaches. First, we conducted ATRP of N‐isopropylacrylamide (NIPAM), then click reaction with azido‐terminated polystyrene (PS‐N3) or poly(tert‐butyl acrylate) (PtBA‐N3) and obtained two ABC miktoarm terpolymers PEG(‐b‐PNIPAM)‐b‐PS and PEG(‐b‐PNIPAM)‐b‐PtBA. Alternatively, we conducted single electron transfer living radical polymerization of tBA and click reaction with PS‐N3 simultaneously to give PEG(‐b‐PtBA)‐b‐PS. All the polymer precursors and miktoarm terpolymers have been characterized by 1H NMR, Fourier transform infrared, gel permeation chromatography, demonstrating that both approaches provided well‐defined ABC miktoarm terpolymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Synthesis and characterization of novel renewable polyesters based on 2,5‐furandicarboxylic acid and 2,3‐butanediol
Authors: Gubbels E. , Jasinska‐Walc L. , Koning C. E.
Published: November 2012

Novel polyesters from 2,5‐furandicarboxylic acid or 2,5‐dimethyl‐furandicarboxylate and 2,3‐butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n‐butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix‐assisted laser ionization‐desorption time‐of‐flight mass spectrometry, electrospray ionization time‐of‐flight mass spectrometry, electrospray ionization quadruple time‐of‐flight mass spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. Fully bio‐based polyesters with number average molecular weights ranging from 2 to 7 kg/mol were obtained which can be suitable for coating applications. The analysis of their thermal properties proved that these polyesters are thermally stable up to 270–300 °C, whereas their glass transition temperature (Tg) values were found between 70 and 110 °C. Furthermore, a material was prepared with a molecular weight of 13 kg/mol, with a Tg of 113 °C. This high Tg would make this material possibly suitable for hot‐fill applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
HARP photoconductive film using CdSe layer with high quantum efficiency
Authors: Miyakawa Kazunori , Ohkawa Yuji , Matsubara Tomoki , Kikuchi Kenji , Kubota Misao , Egami Norifumi
Published: November 2012

We have been developing high‐gain avalanche rushing amorphous photoconductor (HARP) imaging devices to achieve ultra‐high‐sensitivity television cameras with high picture quality. The HARP photoconductive film, which multiplies signal electric charges through an avalanche multiplication phenomenon, is mainly made of amorphous selenium (a‐Se) that has a band gap width of about 2.0 eV. The film has little sensitivity to light with wavelengths over 620 nm. To solve this problem drastically, we developed a new HARP film with a cadmium selenide (CdSe) layer to improve the quantum efficiency for red light. The new film had a quantum efficiency of over 80% across almost all of the visible light region and a multiplication factor of over 10. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Erratum: 10‐GHz 4.69‐W/mm InAlN/GaN HFET on sapphire substrate [Phys. Status Solidi C 9, 855–857 (2012)]
Authors: Feng Zhihong , Liu Bo , Yin Jiayun , Wang Jinjin , Gu Guodong , Dun Shaobo , Cai Shujun
Published: November 2012

Unfortunately, the Fig. 2 in the right column on page 856 was misplaced and should be corrected. The correct figure is shown here (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Regularized partial least squares with an application to NMR spectroscopy
Authors: Allen Genevera I. , Peterson Christine , Vannucci Marina , Maletić‐Savatić Mirjana
Published: November 2012

High‐dimensional data common in genomics, proteomics, and chemometrics often contains complicated correlation structures. Recently, partial least squares (PLS) and Sparse PLS methods have gained attention in these areas as dimension reduction techniques in the context of supervised data analysis. We introduce a framework for Regularized PLS by solving a relaxation of the SIMPLS optimization problem with penalties on the PLS loadings vectors. Our approach enjoys many advantages including flexibility, general penalties, easy interpretation of results, and fast computation in high‐dimensional settings. We also outline extensions of our methods leading to novel methods for non‐negative PLS and generalized PLS, an adoption of PLS for structured data. We demonstrate the utility of our methods through simulations and a case study on proton Nuclear Magnetic Resonance (NMR) spectroscopy data. © 2012 Wiley Periodicals, Inc. Statistical Analysis and Data Mining, 2012
Keeping Your Financial Planner to Yourself: Racial and Cultural Differences in Financial Planner Referrals
Authors: Winchester Danielle D. , Huston Sandra J.
Published: November 2012

Literature suggests that the use of a financial expert by Black households improves savings and investment behaviors. However, these households lack the financial knowledge and sophistication needed to select an appropriate financial expert. This admitted inability results in Black households relying on the recommendations of friends and family in selecting and hiring a financial expert. However results from this study suggest that Blacks who have successfully chosen a financial expert, i.e., are satisfied, are nearly two times (92 %) less likely than non-Blacks to refer their financial planner to others. Decomposition analyses indicate that over 80 % of satisfied Blacks should be willing to provide a referral yet only 50 % do. The largest significant component of the difference in referral rates is culturally based perception differences of the variables used in determining the net benefit of providing a referral.
Sparse fusion systems
Authors: Glesser Adam
Published: November 2012

We define sparse saturated fusion systems and show that, for odd primes, sparse systems are constrained. This simplifies the proof of the Glauberman–Thompson p-Nilpotency Theorem for fusion systems and a related theorem of Stellmacher. We then define a more restrictive class of saturated fusion systems, called extremely sparse systems, that are constrained for all primes.
Bringing Corporate Welfare In
Authors: FARNSWORTH KEVIN
Published: November 2012

One of the consequences of the post-2008 global economic crisis is that it has thrust into the public spotlight the issue of state provision for corporations, putting paid to the myth that capitalism and businesses could ultimately be more profitable, more efficient and more competitive without state interference and direct support. The reality is that corporations of every size and within every sector depend on government support in some way. Hence, while the measures taken by governments in response to the global crisis have been exceptional in their scale, they are not exceptional by design. Rather, direct and indirect state support to corporations – referred to here as corporate welfare – is commonplace and is deeply embedded within the state's operations with various forms of assistance being delivered through social policies. In such an environment, the fact that social policy has very little to say about ‘corporate welfare’ is a serious omission. Bringing corporate welfare into social policy analysis reinforces the potential defence of the welfare state and, at the same time, increases our understanding of how best to balance the needs of private businesses with those of citizens on the one hand, and the burden of paying for welfare on the other. To this end, this paper argues for a deeper recognition, understanding, consideration and embedding of corporate welfare in social policy analysis. The first half of the paper advances conceptually the analysis of corporate welfare, mapping corporate and social welfare along a continuum. The second half provides some empirical evidence of the relative size of corporate and social welfare provision in a number of OECD countries.
Stiffness estimation of a parallel manipulator using image analysis and camera calibration techniques
Authors: Gonzalez-Hernandez Abraham , Castillo-Castaneda Eduardo
Published: November 2012

This work presents a methodology using image analysis to estimate the experimental stiffness of a parallel robot, Parallix LKF-2040, a 3-degree-of-freedom manipulator. The proposed methodology has a simple implementation and can be applied to different architectures of parallel robots. This methodology uses image analysis and camera calibration techniques to estimate compliant displacements of mobile platform produced by several loads at the end effector level, and calculate stiffness in a specific position of mobile platform. Experimental results are presented for different positions within the workspace.
Structure and consequences of the kinetic ballooning/interchange instability in the magnetotail
Authors: Pritchett P. L. , Coroniti F. V.
Published: November 2012

The structure and dynamical consequences of the kinetic ballooning/interchange instability (BICI) that can be excited in the curved magnetic geometry characteristic of the terrestrial plasma sheet are investigated by means of three‐dimensional electromagnetic particle‐in‐cell simulations. Compared with earlier studies that considered a single Bz minimum configuration with an extremely large midtail field, additional simulations are performed in which this maximum is reduced to a more realistic value, the dependence on the values of the plasma beta and of the mass and temperature ratios mi/me and Ti/Te is investigated, and the limiting case of a constant Bz profile is examined. The general properties of the BICI modes are found to be unaltered by these changes. Significantly, the BICI excitation is found not to require an explicit tailward magnetic field gradient; it appears to be sufficient for the entropy to decrease with distance down the tail. The BICI wavelength varies inversely with Bz, and the eigenmodes are strongly field aligned with parallel electron flows comparable to the ion thermal velocity. In the edge of the plasma sheet, the oscillations in Bx and Bz have comparable magnitude. Once excited, the growth of the modes is robust and leads to the formation of intense interchange heads that propagate earthward. When the equatorial plasma beta is on the order of 500 or higher, the Bz field can be driven southward in the wake of the heads. This results in the onset of localized magnetic reconnection and a violent disruption of the plasma sheet.
In vivo early plaque formation on pure titanium and ceramic abutments: a comparative microbiological and SEM analysis
Authors: Rasperini Giulio , Maglione Michele , Cocconcelli Piersandro , Simion Massimo
Published: November 2012

A lack of information exists ahout the influence of different implant ahutment materials on bacterial colonization and its role in the development of perimplantar infections. In order to study these aspects, removable acrylic devices, harboring samples of titanium and novel ceramic abutments (Nobel Biocare) were adapted to the molar‐premolar region in 2 mandibular quadrants of 4 volunteers. Samples of each material were collected at 6 and 24 h, 7 and 14 days. Samples were observed by scanning electron microscopy and bacterial counts were made by means of ATP detection and direct plate count. The electron micrographs demonstrated that the bacteria colonization was already present after 6 h of presence in the oral cavity. After 24 h, both the materials were covered by several layers of bacterial cells. No differences in microbial colonization were observed between titanium and ceramic samples. The microbiological analysis confirmed the presence of relevant amounts of microbial cells on the tested samples. The maximum of colonization was achieved after 24 h in the oral cavity and the bacterial counts remained constant over the 14 day period. No significant differences were observed between the two materials analyzed in this study. In addition, ATP‐bioluminescence technology was demonstrated to be a suitable system to evaluate bacterial colonization in the oral cavity.
Least-squares fitting with errors in the response and
predictor
Authors: Burr T. , Croft S. , Reed B.C.
Published: November 2012

Least squares regression is commonly used in metrology for calibration and estimation. In
regression relating a response y to a predictor x, the
predictor x is often measured with error that is ignored in analysis.
Practitioners wondering how to proceed when x has non-negligible error
face a daunting literature, with a wide range of notation, assumptions, and approaches.
For the model ytrue = β0 + β1   xtrue,
we provide simple expressions for errors in predictors (EIP) estimators
β̂0, EIP for β0 and β̂1, EIP for β1 and for an
approximation to covariance
(β̂0, EIP,
β̂1, EIP). It is assumed that there are measured data
x = xtrue + ex,
and
y = ytrue + ey
with errors ex in x and
ey in y and the
variances of the errors ex and
ey are allowed to depend on
xtrue and ytrue, respectively.
This paper also investigates the accuracy of the estimated cov(β̂0, EIP,
β̂1, EIP) and provides a numerical Bayesian alternative using
Markov Chain Monte Carlo, which is recommended particularly for small sample sizes where
the approximate expression is shown to have lower accuracy than desired.
Traumatic Posterior L4–L5 Fracture Dislocation of the Lumbar Spine: A Case Report
Authors: Zarate-Kalfopulos Baron , Romero-Vargas Samuel , Alcántara-Canseco Cesar , Rosales-Olivarez Luis Miguel , Alpizar-Aguirre Armando , Reyes-Sánchez Alejandro
Published: November 2012

Study Design

Case report.

Objective

The diagnosis and surgical management of a patient with traumatic bilateral posterior dislocation of L4–L5 is presented with a thorough review of the existing literature.

Summary of Background Data

Traumatic dislocation of L4–L5 has been reported in the English literature in only five cases; of these, only two were retrolisthesis.

Methods

A 20-year-old patient was involved in a high-energy vehicular accident and presented with back pain and inability to ambulate. Neurological assessment showed motor strength grade 2/5 in the proximal lower-extremity muscle groups (L1–L3 myotomes) and 0/5 strength distally (L4–S1 myotomes); in addition, incontinence of sphincters was found. X-rays and computed tomography (CT) scan revealed a three-column ligamentous injury with posterior fracture-dislocation of the L4 vertebral body with complete posterior displacement of L4 to L5 vertebral body. The patient underwent posterior approach with reduction, transpedicular fixation, and posterolateral fusion with autologous bone graft.

Results

At 1-year follow-up, the patient had recovered muscular strength in proximal lower-extremities muscle groups, sphincter function had fully recovered, and he was able to ambulate with crutches. There was no recovery of distal extremity sensorimotor function. Plain radiograph and CT scan showed good alignment and progressive maturation of his fusion procedure.

Conclusion

Traumatic retrolisthesis of L4–L5 is a high-energy unstable fracture; reduction of the dislocation is challenging because of the heavy forces acting in the lower lumbar spine. Instrumented fusion restores alignment and maintains segmental stability.
A Radiological Comparison of Anterior Fusion Rates in Anterior Lumbar Interbody Fusion
Authors: McCarthy M. J. H. , Ng L. , Vermeersch G. , Chan D.
Published: November 2012

Aim

To compare anterior fusion in standalone anterior lumbar interbody fusion (ALIF) using cage and screw constructs and anterior cage–alone constructs with posterior pedicle screw supplementation but without posterior fusion.

Methods

Eighty-five patients underwent single- or two-level ALIF procedure for degenerative disk disease or lytic spondylolisthesis (SPL). Posterior instrumentation was performed without posterior fusion in all cases of lytic SPL and when the anterior cage used did not have anterior screw through cage fixation.

Results

Seventy (82%) patients had adequate radiological follow-up at a mean of 19 months. Forty patients had anterior surgery alone (24 single level and 16 two levels) and 30 had front-back surgery (15 single level and 15 two levels). Anterior locked pseudarthrosis was only seen in the anterior surgery–alone group when using the STALIF cage (Surgicraft, Worcestershire, UK) (37 patients). This occurred in five of the single-level surgeries (5/22) and nine of the two-level surgeries (9/15). Fusion was achieved in 100% of the front-back group and only 65% (26/40) of the anterior surgery–alone group.

Conclusion

Posterior pedicle screw supplementation without posterolateral fusion improves the fusion rate of ALIF when using anterior cage and screw constructs. We would recommend supplementary posterior fixation especially in cases where more than one level is being operated.
Well-Being as an Object of Science
Authors: Alexandrova Anna
Published: November 2012

The burgeoning science of well-being makes no secret of being value laden: improvement of well-being is its explicit goal. But in order to achieve this goal its concepts and claims need to be value adequate; that is, they need, among other things, to adequately capture well-being. In this article I consider two ways of securing this adequacy—first, by relying on philosophical theory of prudential value and, second, by the psychometric approach. I argue that neither is fully adequate and explore an alternative. This alternative requires thorough changes in the way philosophers theorize about well-being.
Climate Science Controversies and the Demand for Access to Empirical Data
Authors: McAllister James W.
Published: November 2012

In this article, I discuss calls for access to empirical data within controversies about climate science, as revealed and highlighted by the publication of the e-mail correspondence involving scientists at the Climatic Research Unit at the University of East Anglia in 2009. I identify several arguments advanced for and against the sharing of scientific data. My conclusions are that, whereas transparency in science is to be valued, appeals to an unproblematic category of ‘empirical data’ in climate science do not reflect the complexities of scientific practice in this field.
The Future of Systematics: Tree Thinking without the Tree
Authors: Velasco Joel D.
Published: November 2012

Phylogenetic trees are meant to represent the genealogical history of life and apparently derive their justification from the existence of the tree of life and the fact that evolutionary processes are treelike. However, there are a number of problems for these assumptions. Here it is argued that once we understand the important role that phylogenetic trees play as models that contain idealizations, we can accept these criticisms and deny the reality of the tree while justifying the continued use of trees in phylogenetic theory and preserving nearly all of what defenders of trees have called the “importance of tree thinking.”
Evaluating the Use of an Alternative Breed Type as a Pest Management Strategy
Authors: Epplin Francis M. , Ervin R. Terry
Published: November 2012

Use of an alternative breed type has been proposed as a management strategy for cow‐calf producers confronted with tick‐infested pastures. The objective of the research reported in this paper is to compare the economics of a Brahman crossbreeding (50 percent Brahman‐50 percent British) system with a British crossbreeding system. Because few estimates of breed differences are available, parametric programming was conducted to evaluate the sensitivity of results to base estimates. The proposed strategy to use Brahman crosses on tick‐infested pastures is economically sound over wide ranges of the parameters considered.
Sequential Modeling of White Wheat Marketing Strategies
Authors: Lambert David K. , McCarl Bruce A.
Published: November 2012

A discrete stochastic progamming model is developed to directly maximize expected utility resulting from alternative white wheat marketing strategies. Time‐series and regression techniques are used to simulate post‐harvest price events. Farm characteristics and risk attitudes of a small group of Pacific Northwest wheat producers define the constraints and the objective functions for the model. The sequential formulation of the model, in which price uncertainty is continuously resolved, results in more flexible sales patterns over the marketing year than a nonsequential formulation of the problem. Alternative utility functional forms have little influence on optimal marketing plans.
Can Increasing an Input Price Increase Competitive Profits
Authors: Ladd George W.
Published: November 2012

The envelope theorem asserts that the effect of an input price change on firm profit equals the negative of the quantity of the input used. Students of policy, however, believe that an increase in an input price can result in decreased production and higher product price, and possibly even in higher profit. The theorem is partial equilibrium and is not applicable to situations in which a parametric change generates general equilibrium effects. Conditions are identified under which an input price change can change profit in the same direction. Increasing corn price can increase profits from livestock.
Effects of Selected Credit Programs on Farm Financial Survival
Authors: Batte Marvin T. , Farr Terry J. , Lee Warren F.
Published: November 2012

A computer simulation model is used to determine the effects of policies designed to reduce interest rates and/or loan payments on firm solvency, profitability and cashflow adequacy for a representative eastern Corn Belt farm. A state linked deposit program and the FmHA's Interest Rate Reduction and Debt Deferral programs are analyzed under low, medium and high levels of farm financial leverage. The FmHA Interest Rate Reduction program provides some improvement (relative to the base case) in firm profitability, solvency and cashflow at the 40 percent debt‐to‐asset level, with the ending debt‐to‐asset ratio below that at the beginning of the simulation. This same policy, applied to the 70 percent beginning debt‐to‐asset case, results in increased debt‐to‐asset ratios over, and a negative cashflow at the end of the eight‐year simulation. The linked deposit program provides similar, but substantially less, improvement in these financial measures than the FmHA Reduction plan due to its limit to operating loans. Firm solvency tends to deteriorate over the eight‐year simulation period under the FmHA Debt Deferral scenario, and the 70 percent debt‐to‐asset case is insolvent by year eight.
Multicommodity Export Subsidies
Authors: Haley Stephen L.
Published: November 2012

Recently there has been renewed attention to the welfare‐enhancing effects of export subsidies, in particular targeted export subsidies. This report extends that analysis to the case where cross price effects are significant to trade. In the context of two exportables, a subsidy on one of the goods can be welfare enhancing if a combination of conditions hold. First, the export level of the subsidized good should be low. Second, the rest‐of‐world (ROW) own price substitution elasticity for the subsidized good should be large, and the two exportables should be complementary or only weakly substitutable in ROW. Third, the two exportables should be strongly substitutable in the subsidizing country. Optimal subsidies that incorporate cross effects and targeting can be derived from the spatial equilibrium framework. An example based on USDA's trade liberalization model shows that there are small gains from a targeted U.S. subsidy program for wheat and corn. Sensitivity analysis shows that cross price effects can be important when determining the amount of the subsidies and when evaluating their benefit to the subsidizing country.
Factors Affecting Farmers' Attachments to Production Agriculture
Authors: Beck Roger J. , Frymire Eric H.
Published: November 2012

How economic factors such as the employment structure in rural communities affect the structure of agriculture, particularly through the rural labor market needs to be addressed. This paper uses principal components analysis to form an index reflecting attachment of Illinois farm operators to production agriculture. Between 1978 and 1982 farm operators in Illinois counties dominated by larger farms were more likely to devote more time to available off‐farm employment opportunities than farm operators in counties characterized by smaller farms.
Replacement of Taxes on Farm and Residential Property by Increasing the State Income Tax in Illinois: A Simulation
Authors: Little Randall D. , Fettig Lyle P.
Published: November 2012

Property taxation has long been the focus of debate and criticism. Decreasing reliance on property taxation requires either cutting government services or increasing reliance on alternative revenue sources. This study estimates the effect on the statutory tax burden of partly or fully replacing the farm and residential property tax with an increased state income tax in Illinois, according to groupings of counties.
Farm Operator Characteristics: Implications for Policy
Authors: Lambert Charles D. , Kelley Paul L. , Flinchbaugh Barry L.
Published: November 2012

Use of a single measure, annual gross sales, to define the alleged emerging bimodal structure of U.S. agriculture has serious limitations and implications for: (1) targeting public policy interventions, (2) the structure of research and extension programs at Land Grant Universities, (3) public administrative agencies, (4) farm organizations and (5) farm operators. The authors conclude that multi‐dimensional specification of current and emerging farm structures is essential to determine impacts of public and private programs targeted at the farm operator level. This conclusion was the result of analyzing relationships of nine economic and demographic factors to annual gross sales.
Estimating the Regional Demand for Softwood Lumber in the United States
Authors: Uri Noel D. , Boyd Roy
Published: November 2012

This study examines whether the regional demand for softwood lumber in the United States is dependent on market factors including the price of softwood lumber, the price of other building materials and economic activity, as measured by housing starts. The empirical results suggest that the quantity of softwood lumber demanded does vary in response to fluctuations in the softwood lumber price in three of the four regions considered and it does change with movements in the other explanatory factors (e.g., the price of other building materials and housing starts) in all regions. Finally, in an effort to explain the insignificance of the softwood lumber price in explaining changes in softwood lumber demanded in the West region, regression diagnostics are used. The analysis, however, sheds little light on the result.
Bridging the scales: semantic integration of quantitative SBML in graphical multi-cellular models and simulations with EPISIM and COPASI
Authors: Sütterlin Thomas , Kolb Christoph , Dickhaus Hartmut , Jäger Dirk , Grabe Niels
Published: November 2012

Motivation: Biological reality can in silico only be comprehensively represented in multi-scaled models. To this end, cell behavioural models addressing the multi-cellular level have to be semantically linked with mechanistic molecular models. These requirements have to be met by flexible software workflows solving the issues of different time scales, inter-model variable referencing and flexible sub-model embedding.

Results: We developed a novel software workflow (EPISIM) for the semantic integration of Systems Biology Markup Language (SBML)-based quantitative models in multi-scaled tissue models and simulations. This workflow allows to import and access SBML-based models. SBML model species, reactions and parameters are semantically integrated in cell behavioural models (CBM) represented by graphical process diagrams. By this, cellular states like proliferation and differentiation can be flexibly linked to gene-regulatory or biochemical reaction networks. For a multi-scale agent-based tissue simulation executable code is automatically generated where different time scales of imported SBML models and CBM have been mapped. We demonstrate the capabilities of the novel software workflow by integrating Tyson’s cell cycle model in our model of human epidermal tissue homeostasis. Finally, we show the semantic interplay of the different biological scales during tissue simulation.

Availability: The EPISIM platform is available as binary executables for Windows, Linux and Mac OS X at http://www.tiga.uni-hd.de. Supplementary data are available at http://www.tiga.uni-hd.de/supplements/SemSBMLIntegration.html.

Contact:  niels.grabe@bioquant.uni-heidelberg.de
Visualization and Phospholipid Identification (VaLID): online integrated search engine capable of identifying and visualizing glycerophospholipids with given mass
Authors: Blanchard Alexandre P. , McDowell Graeme S. V. , Valenzuela Nico , Xu Hongbin , Gelbard Sarah , Bertrand Martin , Slater Gary W. , Figeys Daniel , Fai Stephen , Bennett Steffany A. L.
Published: November 2012

Motivation: Establishing phospholipid identities in large lipidomic datasets is a labour-intensive process. Where genomics and proteomics capitalize on sequence-based signatures, glycerophospholipids lack easily definable molecular fingerprints. Carbon chain length, degree of unsaturation, linkage, and polar head group identity must be calculated from mass to charge (m/z) ratios under defined mass spectrometry (MS) conditions. Given increasing MS sensitivity, many m/z values are not represented in existing prediction engines. To address this need, Visualization and Phospholipid Identification is a web-based application that returns all theoretically possible phospholipids for any m/z value and MS condition. Visualization algorithms produce multiple chemical structure files for each species. Curated lipids detected by the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics are provided as high-resolution structures.

Availability: VaLID is available through the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics resources web site at https://www.med.uottawa.ca/lipidomics/resources.html.

Contacts:  lipawrd@uottawa.ca

Supplementary Information:  Supplementary data are available at Bioinformatics online.
Gender Discrimination in Job Ads: Evidence from China *
Authors: Kuhn Peter , Shen Kailing
Published: November 2012

We study explicit gender discrimination in a population of ads on a Chinese Internet job board. Gender-targeted job ads are common, favor women as often as men, and are much less common in jobs requiring higher levels of skill. Employers’ relative preferences for female versus male workers, on the other hand, are more strongly related to the preferred age, height, and beauty of the worker than to job skill levels. Almost two thirds of the variation in advertised gender preferences occurs within firms, and one third occurs within firm*occupation cells. Overall, these patterns are not well explained by a firm-level animus model, by a glass-ceiling model, or by models in which broad occupational categories are consistently gendered across firms. Instead, the patterns suggest a model in which firms have idiosyncratic preferences for particular job-gender matches, which are overridden in skilled positions by factors such as thinner labor markets or a greater incentive to search broadly for the most qualified candidate.
Human Capital and Regional Development *
Authors: Gennaioli Nicola , La Porta Rafael , Lopez-de-Silanes Florencio , Shleifer Andrei
Published: November 2012

We investigate the determinants of regional development using a newly constructed database of 1,569 subnational regions from 110 countries covering 74% of the world’s surface and 97% of its GDP. We combine the cross-regional analysis of geographic, institutional, cultural, and human capital determinants of regional development with an examination of productivity in several thousand establishments located in these regions. To organize the discussion, we present a new model of regional development that introduces into a standard migration framework elements of both the Lucas (1978) model of the allocation of talent between entrepreneurship and work, and the Lucas (1988) model of human capital externalities. The evidence points to the paramount importance of human capital in accounting for regional differences in development, but also suggests from model estimation and calibration that entrepreneurial inputs and possibly human capital externalities help understand the data.