bluuebunny/crossref_metadata_2025_split huggingface dataset:
All‐Atom Molecular Dynamics Simulation of Structure and Diffusion of Hydrophilic Antistatic Agents in Polypropylene
Authors: Long Lianhua , Yang Yingzi , Qiu Feng 
Published: March 2014

AbstractGlycerol monostearate (GMS) is an additive widely used in plastic industry for its good ability to improve the wettability and antistatic property of polymer surfaces. Based on GMS, we propose five additives of different polarity by attuning the number of oxyethyl groups. All‐atom molecular dynamics simulations of these additives in polypropylene (PP) matrix are carried out at temperatures of 300 K, 350 K and 400 K. Detailed molecular conformations are obtained and analyzed. Due to the gauche effect of the dihedral angles, the polar parts of these additives form helix structures. The diffusion coefficient of the additives depends on their molecular conformations and decreases monotonously with increasing polarity. These results are expected to be helpful in rational design of hydrophilic antistatic agents in polymeric materials.
Efficient Acid‐Catalyzed 18F/19F Fluoride Exchange of BODIPY Dyes
Authors: Keliher Edmund J. , Klubnick Jenna A. , Reiner Thomas , Mazitschek Ralph , Weissleder Ralph 
Published: March 2014

AbstractFluorine‐containing fluorochromes are important validation agents for positron emission tomography imaging compounds, as they can be readily validated in cells by fluorescence imaging. In particular, the 18F‐labeled BODIPY‐FL fluorophore has emerged as an important platform, but little is known about alternative 18F‐labeling strategies or labeling on red‐shifted fluorophores. In this study we explore acid‐catalyzed 18F/19F exchange on a range of commercially available N‐hydroxysuccinimidyl ester and maleimide BODIPY fluorophores. We show this method to be a simple and efficient 18F‐labeling strategy for a diverse span of fluorescent compounds, including a BODIPY‐modified PARP‐1 inhibitor, and amine‐ and thiol‐reactive BODIPY fluorophores.
NSF workshop report: Discovering general principles of nervous system organization by comparing brain maps across species
Authors: Striedter Georg F. , Belgard T. Grant , Chen Chun‐Chun , Davis Fred P. , Finlay Barbara L. , Güntürkün Onur , Hale Melina E. , Harris Julie A. , Hecht Erin E. , Hof Patrick R. , Hofmann Hans A. , Holland Linda Z. , Iwaniuk Andrew N. , Jarvis Erich D. , Karten Harvey J. , Katz Paul S. , Kristan William B. , Macagno Eduardo R. , Mitra Partha P. , Moroz Leonid L. , Preuss Todd M. , Ragsdale Clifton W. , Sherwood Chet C. , Stevens Charles F. , Stüttgen Maik C. , Tsumoto Tadaharu , Wilczynski Walter 
Published: March 2014

ABSTRACTEfforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene‐structure‐function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well‐annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross‐species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution. J. Comp. Neurol. 522:1445–1453, 2014. © 2014 Wiley Periodicals, Inc.
Temporal changes of soil physic‐chemical properties at different soil depths during larch afforestation by multivariate analysis of covariance
Authors: Wang Hui‐Mei , Wang Wen‐Jie , Chen Huanfeng , Zhang Zhonghua , Mao Zijun , Zu Yuan‐Gang 
Published: March 2014

AbstractSoil physic‐chemical properties differ at different depths; however, differences in afforestation‐induced temporal changes at different soil depths are seldom reported. By examining 19 parameters, the temporal changes and their interactions with soil depth in a large chronosequence dataset (159 plots; 636 profiles; 2544 samples) of larch plantations were checked by multivariate analysis of covariance (MANCOVA). No linear temporal changes were found in 9 parameters (N, K, N:P, available forms of N, P, K and ratios of N: available N, P: available P and K: available K), while marked linear changes were found in the rest 10 parameters. Four of them showed divergent temporal changes between surface and deep soils. At surface soils, changing rates were 262.1 g·kg−1·year−1 for SOM, 438.9 mg·g−1·year−1 for C:P, 5.3 mg·g−1·year−1 for C:K, and −3.23 mg·cm−3·year−1 for bulk density, while contrary tendencies were found in deeper soils. These divergences resulted in much moderated or no changes in the overall 80‐cm soil profile. The other six parameters showed significant temporal changes for overall 0–80‐cm soil profile (P: −4.10 mg·kg−1·year−1; pH: −0.0061 unit·year−1; C:N: 167.1 mg·g−1·year−1; K:P: 371.5 mg·g−1 year−1; N:K: −0.242 mg·g−1·year−1; EC: 0.169 μS·cm−1·year−1), but without significant differences at different soil depths (P > 0.05). Our findings highlight the importance of deep soils in studying physic‐chemical changes of soil properties, and the temporal changes occurred in both surface and deep soils should be fully considered for forest management and soil nutrient balance.
Design of FIR Filters with Discrete Coefficients Using Ant Colony Optimization
Authors: Tsutsumi Shuntaro , Suyama Kenji 
Published: March 2014

SUMMARYIn this paper, we propose a new design method for linear phase finite impulse response (FIR) filters with discrete coefficients. In a hardware implementation, filter coefficients must be represented as discrete values. The design problem of digital filters with discrete coefficients is formulated as an integer programming problem. But an enormous amount of computational time is required to solve the problem in a strict solver. Recently, ant colony optimization (ACO), a heuristic approach, has been used widely for solving combinational problems such as the traveling salesman problem. In our method, we formulate the design problem as a 0‐1 integer programming problem and solve it by using ACO. Several design examples are presented to show the effectiveness of the proposed method.
Evaluation of Triplet Aromaticity by the Indene–Isoindene Isomerization Stabilization Energy Method
Authors: An Ke , Zhu Jun 
Published: March 2014

AbstractAromaticity, one of the most important concepts in chemistry, has attracted considerable interest from both experimentalists and theoreticians. According to Baird's rule, triplet annulenes with 4n π electrons are aromatic. However, the approach to evaluate the magnitude of the triplet aromaticity is less developed. Herein we apply the indene–isoindene isomerization stabilization energy (ISE) method to evaluate the aromaticity in the triplet state. The reliability of this approach can be demonstrated by the strong correlation of these indene–isoindene ISE values with nucleus‐independent chemical shifts [NICS(1)zz] as well as methyl–methylene ISE values. Large [4n]annulenes have the tendency to be planar to achieve aromaticity in the T1 state. Steric effects play an important role in the stabilities of large [4n]annulene isomers.
New results on perfect channel shortening schemes for MIMO‐OFDM systems
Authors: Singh Istdeo , Giridhar K. 
Published: March 2014

AbstractIn this work, we explore further aspects of the zero‐forcing or perfect channel shortening algorithms described in literature for single‐input multi‐output orthogonal frequency division multiplexing (OFDM) systems. Firstly, we propose a novel perfect channel shortening prefilter (CSP) for multi‐input multi‐output OFDM that admits a CSP of significantly lower order when compared to the perfect shorteners. Secondly, new analytical results are derived for perfect channel shortening algorithms, namely, their post‐shortening signal‐to‐noise ratio (SNR) and their post‐processing SNR. The analytical and simulated results are in close match. Using simulations, we show that the proposed technique outperforms the perfect CSP (zero‐forcing), while performing similar to the optimal channel shortening algorithms based on maximum shortened SNR and the linear minimum mean square error. Our results also indicate that the proposed perfect CSP in MIMO‐OFDM systems is less sensitive to the choice of decoding delay when compared to the linear minimum mean square error CSP, and it can yield substantial gain in practical scenarios where the delay is chosen in an ad‐hoc manner by the CSP. Copyright © 2014 John Wiley & Sons, Ltd.
Onset of hippocampus‐dependent memory impairments in 5XFAD transgenic mouse model of Alzheimer's disease
Authors: Girard Stéphane D. , Jacquet Marlyse , Baranger Kévin , Migliorati Martine , Escoffier Guy , Bernard Anne , Khrestchatisky Michel , Féron François , Rivera Santiago , Roman François S. , Marchetti Evelyne 
Published: March 2014

ABSTRACTThe 5XFAD mice are an early‐onset transgenic model of Alzheimer's disease (AD) in which amyloid plaques are first observed between two and four months of age in the cortical layer five and in the subiculum of the hippocampal formation. Although cognitive alterations have been described in these mice, there are no studies that focused on the onset of hippocampus‐dependent memory deficits, which are a hallmark of the prodromal stage of AD. To identify when the first learning and memory impairments appear, 5XFAD mice of two, four, and six months of age were compared with their respective wild‐type littermates using the olfactory tubing maze, which is a very sensitive hippocampal‐dependent task. Deficits in learning and memory started at four months with a substantial increase at six months of age while no olfactory impairments were observed. The volumetric study using magnetic resonance imaging of the whole brain and specific areas (olfactory bulb, striatum, and hippocampus) did not reveal neuro‐anatomical difference. Slight memory deficits appeared at 4 months of age in correlation with an increased astrogliosis and amyloid plaque formation. This early impairment in learning and memory related to the hippocampal dysfunction is particularly suited to assess preclinical therapeutic strategies aiming to delay or suppress the onset of AD. © 2014 Wiley Periodicals, Inc.
The use of compliant layer prosthetic components in orthopedic joint repair and replacement: A review
Authors: St. John Kenneth R. 
Published: March 2014

AbstractThe surgical repair or treatment of degenerative joint disease has traditionally involved the substitution of synthetic materials for one or both surfaces of the joint. Engineering thermoplastics, metals, and ceramics have either been widely accepted or experimentally evaluated for use as bearing surfaces in these prostheses. When engineering thermoplastics are used, the opposing surface is a metal or a ceramic, but metal‐on‐metal, metal‐on‐ceramic, and ceramic‐on‐ceramic have also been used or tested. Researchers have sought the opportunity to utilize materials with compressive mechanical properties more closely matching those of the natural articular cartilage. This review discusses the theory, testing, and application of elastomers for one bearing component of articular joint prostheses. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1332–1341, 2014.
Porous gelatin–siloxane hybrid scaffolds with biomimetic structure and properties for bone tissue regeneration
Authors: Lei Bo , Shin Kwan‐Ha , Koh Young‐Hag , Kim Hyoun‐Ee 
Published: March 2014

AbstractWe produced highly porous gelatin–siloxane (GLA‐S) hybrid scaffolds with biomimetic anisotropic porous structure, physiochemical properties, mechanical behaviors and biological functions by treating gelatin–siloxane hybrid gels in an ammonium hydroxide solution. The siloxane used as an inorganic phase could effectively crosslink the gelatin polymer, which allowed for the unidirectional enlargement of ammonia vacuoles during ammonium hydroxide treatment. This created aligned pores in an axial direction when the siloxane contents (10 and 20 wt %) were high. In addition, the gelatin polymer could be uniformly hybridized with the siloxane phase at the molecular level, while intense interaction between these two phases could be achieved. This resulted in a significant increase in mechanical properties. The GLA‐S hybrid scaffold with a siloxane content of 10 wt % showed reasonably high compressive yield strength of 4.2 ± 0.1 MPa and compressive modulus of 84 ± 5 MPa at a porosity of 86 vol %, which would be comparable to those of natural cancellous bone. In addition, the GLA‐S hybrid scaffold had good biocompatibility assessed by in vitro cell tests using pre‐osteoblast MC3T3‐E1 cells. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1528–1536, 2014.
Drastic Tuning of the Photonic Properties of «(Push–Pull)n» trans‐Bis(ethynyl)bis(Tributylphosphine)Platinum(II)‐Containing Polymers
Authors: Wang Xiaorong , Fortin Daniel , Brisard Gessie , Harvey Pierre D. 
Published: March 2014

The trans‐Pt(PBu3)2Cl2 complex reacts with 1 equiv. of 2,6‐diethynyl‐AQ and 2 equiv. of 2‐ethynyl‐AQ (AQ = anthraquinone) to form the polymer (trans‐Pt(2,6‐diethynyl‐AQ)2(PBu3)2)n, 1, and the model compounds, 2, trans‐Pt(PBu3)2(2‐ethynyl‐AQ)2 (in a 20:1 ratio as trans‐(2a) and cis‐(2b) rotational isomers), respectively. These redox‐active and luminescent materials have been characterized by gel permeation chromatography, thermal gravimetric analysis, X‐ray crystallography, electrochemistry, photophysics, and DFT computations (B3LYP). The typical π,π* T2→S0 phosphorescence centered on the trans‐Pt(PBu3)2(aryl)2 chromophore, [Pt], generally encountered for the analogous polymers (trans‐Pt(PBu3)2(aryl)2‐acceptor)n (acceptor = quinonediimine, QN2; anthraquinone diimine, AQN2), for which the CT T1→S0 emission is silent, has been completely annihilated and replaced by a red‐shifted T1→S0 emission in 1 and 2a, which arise from a triplet charge transfer excited state [Pt]→AQ.
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A detection algorithm for drug‐induced liver injury in medical information databases using the Japanese diagnostic scale and its comparison with the Council for International Organizations of Medical Sciences/the Roussel Uclaf Causality Assessment Method scale
Authors: Hanatani Tadaaki , Sai Kimie , Tohkin Masahiro , Segawa Katsunori , Kimura Michio , Hori Katsuhito , Kawakami Junichi , Saito Yoshiro 
Published: March 2014

ABSTRACTPurposeDrug‐induced liver injury (DILI) is one of the primary targets for pharmacovigilance using medical information databases (MIDs). Because of diagnostic complexity, a standardized method for identifying DILI using MIDs has not yet been established. We applied the Digestive Disease Week Japan 2004 (DDW‐J) scale, a Japanese clinical diagnostic criteria for DILI, to a DILI detection algorithm, and compared it with the Council for International Organizations of Medical Sciences/the Roussel Uclaf Causality Assessment Method (CIOMS/RUCAM) scale to confirm its consistency. Characteristics of DILI cases identified by the DDW‐J algorithm were examined in two Japanese MIDs.MethodsUsing an MID from the Hamamatsu University Hospital, we constructed a DILI detection algorithm on the basis of the DDW‐J scale. We then compared the findings between the DDW‐J and CIOMS/RUCAM scales. We examined the characteristics of DILI after antibiotic treatment in the Hamamatsu population and a second population that included data from 124 hospitals, which was derived from an MID from the Medical Data Vision Co., Ltd. We performed a multivariate logistic regression analysis to assess the possible DILI risk factors.ResultsThe concordance rate was 79.4% between DILI patients identified by the DDW‐J and CIOMS/RUCAM; the Spearman rank correlation coefficient was 0.952 (P < 0.0001). Men showed a significantly higher risk for DILI after antibiotic treatments in both MID populations.ConclusionsThe DDW‐J and CIOMS/RUCAM algorithms were equivalent for identifying the DILI cases, confirming the utility of our DILI detection method using MIDs. This study provides evidence supporting the use of MID analyses to improve pharmacovigilance. Copyright © 2014 John Wiley & Sons, Ltd.
Optimization of an α‐(Amino acid)‐N‐carboxyanhydride polymerization using the high vacuum technique: Examining the effects of monomer concentration, polymerization kinetics, polymer molecular weight, and monomer purity
Authors: Kowtoniuk Robert A. , Pei Tao , DeAngelo Caitlin M. , Waldman Jacob H. , Guidry Erin N. , Williams J. Michael , Garbaccio Robert M. , Barrett Stephanie E. 
Published: March 2014

ABSTRACTl‐Ornithine‐based poly(peptides) have been widely utilized in the field of drug delivery, however few studies have been conducted examining the details of polymerization. In this article, the effects of monomer concentration, polymerization kinetics, polymer molecular weight and monomer purity were investigated using l‐carboxybenzyl (Cbz)‐ornithine as a model monomer. The mechanism of polymerization herein follows the normal amine mechanism to produce poly(peptides) having controlled molecular weights, known chain ends and a narrow polydispersity index (PDI). A preferred monomer concentration range was determined, which required minimal polymerization times and allowed for predictable and reproducible molecular weights with narrow PDIs. The impact of monomer purity on the polymerization was established and monomer purification conditions are reported, which produce high‐purity monomer after a single recrystallization. Additionally, the optimized polymerization conditions and monomer purification protocol were combined with a sequential monomer addition technique to produce high molecular weight poly(ornithine) with a narrow PDI and known chain ends. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1385–1391
Two‐Step direct arylation for synthesis of naphthalenediimide‐based conjugated polymer
Authors: Nohara Yuta , Kuwabara Junpei , Yasuda Takeshi , Han Liyuan , Kanbara Takaki 
Published: March 2014

ABSTRACTA naphthalenediimide (NDI)‐based conjugated polymer was synthesized by a two‐step direct C‐H arylation sequence. In the first step, two ethylenedioxythiophene units were coupled to NDI by direct arylation. In the second step, the direct arylation polycondensation of the monomer, formed in the first step, with 2,7‐dibromo‐9,9‐dioctylfluorene afforded the corresponding NDI‐based conjugated polymer (PEDOTNDIF) with molecular weight of 21,500 in 91% yield. The optical and electrochemical properties of the polymer were evaluated. The polymer showed ambipolar behavior in organic field‐effect transistors (OFETs). The electron mobility of PEDOTNDIF was estimated to be 2.3 × 10−6 cm2 V−1 s−1 using an OFET device with source‐drain (S‐D) Au electrodes. A modified OFET device with S‐D MgAg electrodes increased the electron mobility for PEDOTNDIF to 1.0 × 10−5 cm2 V−1 s−1 due to the more suitable work function of these electrodes, which reduced the injection barrier to the semiconducting polymer. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1401–1407
Spatial Pattern of Phytoplankton Based on the Morphology‐Based Functional Approach along a River–Floodplain Gradient
Authors: Mihaljević M. , Stević F. , Špoljarić D. , Pfeiffer T. Žuna 
Published: March 2014

AbstractCurrent efforts to yield an appropriate method that would simplify the use of phytoplankton in the ecological evaluation of freshwaters resulted in different approaches based on clustering phytoplankton organisms. In this study, we applied the morphology‐based functional group (MBFG) concept to determine the spatial changes of phytoplankton in the natural riverine floodplain of the alluvial reaches of the Danube River along the horizontal gradient from the river towards the floodplain habitats.The obtained results showed that the magnitude of environmental changes depended on alternations in hydrological variables (hydropattern and water level) that influenced changes in the physical and chemical conditions. High‐intensity flood pulses caused environmental homogenizations and nitrate enrichment of the floodplain habitats. Phytoplankton dynamics were strongly associated with the environmental changes, and using the MBFG approach, two basic hydrological conditions were identified: inundation phase dominated by diatoms (GVI) and isolation phase dominated by filamentous cyanobacteria (GIII). Total diatom biomass decreased along the floodplain gradient with a diminishing of physical constraints, and site‐specific variables became more important in favouring diatom assemblages. The different response of cyanobacterial species to mixing regime was of particular significance for species successions during bloom period. Altogether, classifying very diverse diatoms (centrics and pennates and planktonic and benthic) and cyanobacterial taxa into single groups represents a weakness of the MBFG approach, which might make it impossible to reflect all the ecological differences governed by environmental constraints along river–floodplain gradients. Copyright © 2014 John Wiley & Sons, Ltd.
Concurrency control of bulk access transactions on a parallel disk database machine
Authors: Ohmori Tadashi , Kitsuregawa Masaru , Tanaka Hidehiko 
Published: March 2014

AbstractA scheme for concurrency control of bulk access transactions on a Shared‐Nothing database machine is described. A “weighted transaction precedence graph” that expresses transaction cost as well as serializability and a cautions scheduler based on it are capable of producing serializable schedules with decreased data and resource contention. In simulations the new scheduler achieved throughout levels 1.3 to 2 times those attainable with conventional locking protocols.