bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on strength and gelation time of polyacrylamide/polyethyleneimine composite gels reinforced with coal fly ash for water shut‐off treatment
Authors: Adewunmi Ahmad A. , Ismail Suzylawati , Sultan Abdullah S. 
Published: September 2014

ABSTRACTThis study investigates the influence of coal fly ash (CFA) as a reinforcing material on the strength and the gelation of polyacrylamide (PAM)/polyethyleneimine (PEI) composite gels. Pure PAM/PEI gel and PAM/PEI gels containing CFA up to 2 wt % were synthesized via the cross‐linking reaction between PAM and PEI solutions at room temperature (25°C) in distilled water dispersed with CFA. The strength of each composite gel was measured at temperature of 80°C, while the gelation was determined from 80°C to 95°C. Rheological measurements indicated that the strength of PAM/PEI composite gels filled with CFA contents was significantly rigid and stronger than that of pure PAM/PEI gel as a result of the enhanced interfacial interaction of well‐dispersed CFA contents in PAM/PEI gel matrix. The gelation times of PAM/PEI gels containing CFA up to 2 wt % deviated from the gelation time of pure PAM/PEI gel. It was further observed that an increase in temperature resulted in a decrease in gelation time of PAM/PEI gel containing 2 wt % CFA. The scanning electron microscopy revealed the surface micrographs of PAM/PEI gels filled with CFA to be very dense without any noticeable micropores. The micropores were absent as scanning was performed on the dried composite gels. It also establishes the strong interaction between CFA and PAM/PEI gel matrix. Experimental findings showed that PAM/PEI composite gels reinforced with CFA are potential candidates for total water shut‐off treatment in oilfields. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41392.
Impact of pregabalin treatment on synaptic plasticity and glial reactivity during the course of experimental autoimmune encephalomyelitis
Authors: Silva Gleidy A. A. , Pradella Fernando , Moraes Adriel , Farias Alessandro , dos Santos Leonilda M. B. , de Oliveira Alexandre L. R. 
Published: September 2014

AbstractBackgroundMultiple sclerosis (MS) is an autoimmune and neurodegenerative disease that affects young adults. It is characterized by generating a chronic demyelinating autoimmune inflammation in the central nervous system. An experimental model for studying MS is the experimental autoimmune encephalomyelitis (EAE), induced by immunization with antigenic proteins from myelin.AimsThe present study investigated the evolution of EAE in pregabalin treated animals up to the remission phase.Methods and resultsThe results demonstrated a delay in the onset of the disease with statistical differences at the 10th and the 16th day after immunization. Additionally, the walking track test (CatWalk) was used to evaluate different parameters related to motor function. Although no difference between groups was obtained for the foot print pressure, the regularity index was improved post treatment, indicating a better motor coordination. The immunohistochemical analysis of putative synapse preservation and glial reactivity revealed that pregabalin treatment improved the overall morphology of the spinal cord. A preservation of circuits was depicted and the glial reaction was downregulated during the course of the disease. qRT‐PCR data did not show immunomodulatory effects of pregabalin, indicating that the positive effects were restricted to the CNS environment.ConclusionsOverall, the present data indicate that pregabalin is efficient for reducing the seriousness of EAE, delaying its course as well as reducing synaptic loss and astroglial reaction.
Improvement of a Gas Intake Device and a Gas Mixing Study in a Large‐Scale Vessel
Authors: Bai Chunhua , Fan Baolong , Li Bin 
Published: September 2014

AbstractGas mixing is a common process in chemical engineering. For actual industrial manufacturing of chemicals, most reactions commonly run in reactors or reaction vessels with large volumes (over 10 m3). In order to simulate a gas mixing process in a sealed reactor, and finally to improve the mixing effect between the gases, here the mixing process between methane and air in a reaction vessel with a volume of 10 m3 was studied via several approaches. Several specific evaluation indexes, including the mixing degree, the maximum concentration difference, and the mixing time, were obtained and recorded to evaluate the mixing effect on the gases. After a series of experiments targeting the determination of the size and pressure difference values of the gas intake device, the mixing effect between methane and air was finally optimized. The mixing degree was found to reach 0.97 within 1 h of monitoring, and the mixing time was decreased by 1700 % from the original situation.
Effect of Particle Shape on Inline Particle Size Measurement Techniques
Authors: Mostafavi Maryam , Petersen Sandra , Ulrich Joachim 
Published: September 2014

AbstractThe influence of the particle shape on the results of different measuring techniques was investigated. Considered were single‐frequency ultrasound technique, 3D optical reflectance measurement (advanced particle analyzing system with multi capture signal technology), and focused‐beam reflectance measurement probes as techniques which are usable inline and in suspension density ranges usually present in industrial crystallization processes. Advantages and shortcomings of these techniques are compared and discussed.
From Eight‐Membered 10π Electron Sulfur–Nitrogen Cycles to Bicycles and Cages: A Theoretical Approach
Authors: Gleiter Rolf , Haberhauer Gebhard , Woitschetzki Sascha 
Published: September 2014

AbstractA simple way of rationalizing the structures of cyclic, bicyclic, and tricyclic sulfur–nitrogen species and their congeners is presented. Starting from a planar tetrasulfur tetranitride with 12π electrons, we formally derived on paper a number of heterocyclic eight‐membered 10π electron species by reacting the 3p orbitals of two opposite sulfur centers with one radical each, or by replacing these centers by other atoms with five (P) or four (Si, C) valence electrons. This led to planar aromatic 10π electron systems, nonplanar bicyclic structures with a transannular SS bond, and tricyclic structures by bridging the planar rings with an acceptor or donor unit. The final structures depend on the number of π electrons in the bridges. Intermediate biradicals are stabilized by Jahn–Teller distortion, giving transannular SS bonds between the NSN units. This procedure may be summarized by two rules, which provide a rationale for the structures of a large number of sulfur–nitrogen‐based molecules. The long bonds between the NSN units show a p character of >95 %. The qualitative results have been compared with known molecular structures and the results of B3LYP/cc‐pVTZ calculations as well as CASSCF and CASVB calculations. B3LYP/cc‐pVTZ calculations have also provided the UV/Vis spectra and the NICS values of the planar 10π systems.
Computational model of matrix remodeling and entrenchment in the free‐floating fibroblast‐populated collagen lattice
Authors: Simon D. D. , Murtada S.‐I. , Humphrey J. D. 
Published: September 2014

SUMMARYTissue equivalents represent excellent model systems for elucidating principles of mechanobiology and for exploring methods to improve the functionality of tissue‐engineered constructs. The simplest tissue equivalent is the free‐floating fibroblast‐populated collagen lattice. Although introduced over 30 years ago, the associated mechanics of the cell‐mediated compaction of this lattice was only recently analyzed in detail. The goal of this paper was to build on this recent stress analysis by developing a computational model of the evolving geometry, regionally varying material properties and cell stresses, and overall residual stress fields during the first two days of compaction. Baseline results were found to agree well with most experimental observations, namely evolving changes in radius, thickness, and material symmetry, yet hypothesis testing revealed aspects of the mechanobiology that require more experimental attention. Given the generality of the proposed framework, we submit that modifications and refinements can be used to study many similar systems and thereby help guide future experiments. Copyright © 2014 John Wiley & Sons, Ltd.
A Multifrequency Virtual Spectrometer for Complex Bio‐Organic Systems: Vibronic and Environmental Effects on the UV/Vis Spectrum of Chlorophyll a
Authors: Barone Vincenzo , Biczysko Malgorzata , Borkowska‐Panek Monika , Bloino Julien 
Published: September 2014

AbstractThe subtle interplay of several different effects means that the interpretation and analysis of experimental spectra in terms of structural and dynamic characteristics is a challenging task. In this context, theoretical studies can be helpful, and as such, computational spectroscopy is rapidly evolving from a highly specialized research field toward a versatile and widespread tool. However, in the case of electronic spectra (e.g. UV/Vis, circular dichroism, photoelectron, and X‐ray spectra), the most commonly used methods still rely on the computation of vertical excitation energies, which are further convoluted to simulate line shapes. Such treatment completely neglects the influence of nuclear motions, despite the well‐recognized notion that a proper account of vibronic effects is often mandatory to correctly interpret experimental findings. Development and validation of improved models rooted into density functional theory (DFT) and its time‐dependent extension (TD‐DFT) is of course instrumental for the optimal balance between reliability and favorable scaling with the number of electrons. However, the implementation of easy‐to‐use and effective procedures to simulate vibrationally resolved electronic spectra, and their availability to a wide community of users, is at least equally important for reliable simulations of spectral line shapes for compounds of biological and technological interest. Here, such an approach has been applied to the study of the UV/Vis spectra of chlorophyll a. The results show that properly tailored approaches are feasible for state‐of‐the‐art computational spectroscopy studies, and allow, with affordable computational resources, vibrational and environmental effects on the spectral line shapes to be taken into account for large systems.
Abundance, diversity, and feeding behavior of coral reef butterflyfishes at Lord Howe Island
Authors: Pratchett Morgan S. , Hoey Andrew S. , Cvitanovic Christopher , Hobbs Jean‐Paul A. , Fulton Christopher J. 
Published: September 2014

AbstractEndemic species are assumed to have a high risk of extinction because their restricted geographic range is often associated with low abundance and high ecological specialization. This study examines the abundance of Chaetodon butterflyfishes at Lord Howe Island in the south‐west Pacific, and compares interspecific differences in local abundance to the feeding behavior and geographic range of these species. Contrary to expected correlations between abundance and geographic range, the single most abundant species of butterflyfish was Chaetodon tricinctus, which is endemic to Lord Howe Island and adjacent reefs; densities of C. tricinctus (14.1 ± 2.1 SE fish per 200m2) were >3 times higher than the next most abundant butterflyfish (Chaetodon melannotus), and even more abundant than many other geographically widespread species. Dietary breadth for the five dominant butterflyfishes at Lord Howe Island was weakly and generally negative correlated with abundance. The endemic C. tricinctus was a distinct outlier in this relationship, though our extensive feeding observations suggest some issues with the measurements of dietary breadth for this species. Field observations revealed that all bites taken on benthic substrates by C. tricinctus were from scleractinian corals, but adults rarely, if ever, took bites from the benthos, suggesting that they may be feeding nocturnally and/or using mid‐water prey, such as plankton. Alternatively, the energetic demands of C. tricinctus may be fundamentally different to other coral‐feeding butterflyfishes. Neither dietary specialization nor geographic range accounts for interspecific variation in abundance of coral reef butterflyfishes at Lord Howe Island, while much more work on the foraging behavior and population dynamics of C. tricinctus will be required to understand its’ abundance at this location.
Impedance Analysis of Single Melanoma Cells in Microfluidic Devices
Authors: Chiang Yang , Jang Ling‐Sheng , Tsai Sung‐Lin , Chen Ming‐Kun , Wang Min‐Haw 
Published: September 2014

AbstractThe electrical impedance analysis of single cells can provide information on cells’ pathological condition in various environments. Cell electrical properties are affected by factors such as the location, adhesion, and size of the cell. The proposed microfluidic device captures a single cell, maintains growth conditions, and allows single‐melanoma‐cell impedance to be measured using an impedance analyzer and a function generator. The rate of impedance variation (ROIV) can be used to determine cell growth conditions. Cellular apoptosis affects cell size and membrane surface area, and thus the electrical properties of cells. At 24 h without Antrodia cinnamomea (AC) addition, ROIV was 15.23 %, 17.04 %, and 12.60 % at temperatures of 34 °C, 37 °C, and 40 °C, respectively. At 24 h and 37 °C, ROIV was 17.04 %, 40.37 %, and 45.02 % for AC concentrations of 0, 20, and 40 µL/mL, respectively. The results show that the cell impedance variation of cells cultured without AC is much lower than that of cells cultured with AC. Regarding cellular morphology, with AC addition, the cells shrank obviously after 24 h, whereas they barely shrank without AC addition.
Sensitive Voltammetric Sensor Based on Boron‐Doped Diamond Electrode for Determination of the Chemotherapeutic Drug Methotrexate in Pharmaceutical and Biological Samples
Authors: Šelešovská Renáta , Janíková‐Bandžuchová Lenka , Chýlková Jaromíra 
Published: September 2014

AbstractA novel sensitive voltammetric method for the determination of an important chemotherapeutic drug, methotrexate, was designed using a bare boron‐doped diamond electrode in connection with differential pulse voltammetry. Methotrexate provided one well developed oxidation peak suitable for analytical purposes at about +1000 mV (vs. Ag/AgCl electrode) in an acidic medium. The voltammetric behavior of methotrexate in dependence of pH of the supporting electrolyte and scan rate has been investigated using cyclic voltammetry and DC voltammetry, respectively, to select the suitable experimental parameters. The optimum conditions for its determination using differential pulse voltammetry have been found to be 0.05 mol L−1 H2SO4 with a limit of detection of 1.0×10−8 mol L−1 and a linear dynamic range from 5×10−8 to 2×10−5 mol L−1. Calculated values of relative standard deviations of repeated determinations (n≥5) in various concentration levels of methotrexate did not exceed 4 %. The influence of possible interfering agents was studied as well. Finally, practical applicability of the newly proposed method was verified by analysis of real drug preparations and spiked human urine. The calculated recovery values ranged from 99.2 to 101.4 %.
Comparing Computational Methods for Identification of Allele‐Specific Expression based on Next Generation Sequencing Data
Authors: Liu Zhi , Yang Jing , Xu Huayong , Li Chao , Wang Zhen , Li Yuanyuan , Dong Xiao , Li Yixue 
Published: September 2014

ABSTRACTAllele‐specific expression (ASE) studies have wide‐ranging implications for genome biology and medicine. Whole transcriptome RNA sequencing (RNA‐Seq) has emerged as a genome‐wide tool for identifying ASE, but suffers from mapping bias favoring reference alleles. Two categories of methods are adopted nowadays, to reduce the effect of mapping bias on ASE identification—normalizing RNA allelic ratio with the parallel genomic allelic ratio (pDNAar) and modifying reference genome to make reads carrying both alleles with the same chance to be mapped (mREF). We compared the sensitivity and specificity of both methods with simulated data, and demonstrated that the pDNAar, though ideally practical, was lower in sensitivity, because of its lower mapping rate of reads carrying nonreference (alternative) alleles, although mREF achieved higher sensitivity and specificity for its efficiency in mapping reads carrying both alleles. Application of these two methods in real sequencing data showed that mREF were able to identify more ASE loci because of its higher mapping efficiency, and able to correcting some seemly incorrect ASE loci identified by pDNAar due to the inefficiency in mapping reads carrying alternative alleles of pDNAar. Our study provides useful information for RNA sequencing data processing in the identification of ASE.
Palladium‐Catalyzed Decarbonylative Rearrangement of N‐Allenyl Seleno‐ and Tellurocarbamates
Authors: Shiro Daisuke , Nagai Hiroyuki , Fujiwara Shin‐ichi , Tsuda Susumu , Iwasaki Takanori , Kuniyasu Hitoshi , Kambe Nobuaki 
Published: September 2014

ABSTRACTDecarbonylative rearrangement of seleno‐ and tellurocarbamates carrying an allenyl group on the nitrogen was found to proceed in the presence of a palladium catalyst to afford 3‐chalcogeno‐1‐azadienes. This transformation may involve oxidative addition of Pd to a carbon–chalcogen bond, decarbonylation from a carbamoylpalladium unit (R2N‐C(O)‐PdChPh: Ch = Se or Te), Pd shift, and reductive elimination.
Adhesive interface and bond strength of endodontic sealers to root canal dentine after immersion in phosphate‐buffered saline
Authors: Tedesco Maybell , Felippe Mara Cristina Santos , Felippe Wilson Tadeu , Alves Ana Maria Hecke , Bortoluzzi Eduardo Antunes , Teixeira Cleonice Silveira 
Published: September 2014

ABSTRACTThis study evaluated the bond strength (BS) and the adhesive interface of four endodontic sealers to root canal dentine, before, and after immersion in phosphate buffered saline (PBS) to simulate an in vivo environment. Eighty roots were instrumented using ProTaper rotatory files, under irrigation with 17% EDTA and 1% NaOCl. Posteriorly were divided into four groups (n = 20) according to the sealer used: Endofill, AH Plus, Sealapex, and MTA Fillapex. Each group was divided into two subgroups (n = 10) and stored at 37°C immersed in water for 7 days and in PBS for 60 days. From each subgroup, 1 mm thick sections were obtained. One section of each region (coronal, middle, and apical) was submitted to the push‐out test and failures were observed. Twelve sections of each subgroup (four from each region) were evaluated under SEM. Three‐way ANOVA evaluation for BS showed significant differences between groups and regions (P < 0.0001), but not between subgroups (P > 0.05). AH Plus had significantly higher BS than the others sealers, regardless of the analyzed subgroup (Tukey's test, P < 0.5). The most common failures were adhesive to dentine and cohesive of the sealer. The SEM evaluation (Kruskal–Wallis, Mann–Whitney) showed homogeneous adhesive interface formed and sealer tags in all groups with significant statistical differences with AH Plus, regardless of PBS immersion. AH Plus was superior to the other sealers for both BS and quality of interface formation. Immersion in PBS did not interfere on BS or adhesive interface of the sealers tested. Microsc. Res. Tech. 77:1015–1022, 2014. © 2014 Wiley Periodicals, Inc.
Pathogenesis and classification of intrahepatic cholangiocarcinoma: different characters of perihilar large duct type versus peripheral small duct type
Authors: Aishima Shinichi , Oda Yoshinao 
Published: September 2014

Abstract Intrahepatic cholangiocarcinomas (ICCs) are made up of heterogenous carcinomas arising from different anatomical sites of the liver. Two types of candidate stem/progenitor cells of the biliary tree are postulated to exist at the peribiliary glands for large bile ducts and at the canals of Hering for small ducts and hepatocytes. According to the recent observations, ICCs can be subclassified into two types: tumors involving the large bile ducts comparable in size to the intrahepatic second branches and composed of a tubular or papillary component with tall columnar epithelium, and tumors involving the smaller duct than segmental branches and composed of small tubules with cuboidal epithelium. Perihilar large duct type ICCs can be interpreted as arising from large bile duct type ICCs, and peripheral small duct type ICCs may arise from small bile duct type or ductular type ICCs. Chronic biliary inflammation induces neoplastic change of the large bile ducts and thereby progression to the perihilar large duct type ICC, which can be grossly classified into periductal filtrating type ICC and intraductal growth type ICC, while chronic hepatitis or cirrhosis induces mass‐forming peripheral small duct type ICC. The different morphological and molecular features, including stromal components and tumor vasculature, support the hypothesis that perihilar large duct type ICCs and peripheral small duct type ICCs arise from different backgrounds, have different carcinogenetic pathways, and exhibit different biologic behaviors.
Eating with a saw for a jaw: Functional morphology of the jaws and tooth‐whorl inHelicoprion davisii
Authors: Ramsay Jason B. , Wilga Cheryl D. , Tapanila Leif , Pruitt Jesse , Pradel Alan , Schlader Robert , Didier Dominique A. 
Published: September 2014

ABSTRACTThe recent reexamination of a tooth‐whorl fossil ofHelicoprioncontaining intact jaws shows that the symphyseal tooth‐whorl occupies the entire length of Meckel's cartilage. Here, we use the morphology of the jaws and tooth‐whorl to reconstruct the jaw musculature and develop a biomechanical model of the feeding mechanism in these early Permian predators. The jaw muscles may have generated large bite‐forces; however, the mechanics of the jaws and whorl suggest thatHelicoprionwas better equipped for feeding on soft‐bodied prey. Hard shelled prey would tend to slip anteriorly from the closing jaws due to the curvature of the tooth‐whorl, lack of cuspate teeth on the palatoquadrate (PQ), and resistance of the prey. When feeding on soft‐bodied prey, deformation of the prey traps prey tissue between the two halves of the PQ and the whorl. The curvature of the tooth‐whorl and position of the exposed teeth relative to the jaw joint results in multiple tooth functions from anterior to posterior tooth that aid in feeding on soft‐bodied prey. Posterior teeth cut and push prey deeper into the oral cavity, while middle teeth pierce and cut, and anterior teeth hook and drag more of the prey into the mouth. Furthermore, the anterior‐posterior edges of the teeth facilitate prey cutting with jaw closure and jaw depression. The paths traveled by each tooth during jaw depression are reminiscent of curved pathways used with slashing weaponry such as swords and knifes. Thus, the jaws and tooth‐whorl may have formed a multifunctional tool for capturing, processing, and transporting prey by cyclic opening and closing of the lower jaw in a sawing fashion. J. Morphol. 276:47–64, 2015. © 2014 Wiley Periodicals, Inc.
The politics of employment liability
Authors: Munyon Timothy P. , Kane‐Frieder Rachel E. 
Published: September 2014

SummaryEmployment liability is an important check and balance against employee harm at work. In practice, however, an inadvertent consequence of employment liability is a potential shift in power from organizations to employees that affects subsequent managerial decision making. In this Incubator, we discuss behavioral and attitudinal ramifications of employment liability at work. Copyright © 2014 John Wiley & Sons, Ltd.