bluuebunny/crossref_metadata_2025 huggingface dataset:
Air pollutants cause release of hydrogen peroxide and interleukin‐8 in a human primary nasal tissue culture model
Authors: Cho Do‐Yeon , Le Wei , Bravo Dawn T. , Hwang Peter H. , Illek Beate , Fischer Horst , Nayak Jayakar V.
Published: November 2014

Background

A component of primary innate defense of the nasal mucosa against inhaled pathogens includes continuous, low‐level release of hydrogen peroxide (H2O2) into luminal secretions. Epidemiologically, an association exists between poor air quality and increased prevalence of sinonasal disease. To understand the effects of particulate matter (PM) in nasal mucosa, we studied the release of H2O2 and interleukin 8 (IL‐8) after PM exposure.

Methods

Human nasal specimens were collected from surgery and cultured in serum‐free growth medium. Cell integrity and recovery during culture was monitored by lactate dehydrogenase (LDH) release into the medium. Cultures were exposed to PM for 24 hours in the presence/absence of diphenyleneiodonium sulfate (DPI; a nicotinamide adenine dinucleotide phosphate [NADPH] oxidase inhibitor). Luminex cytokine and Amplex‐Red H2O2 assays were performed.

Results

LDH levels dropped rapidly within 2 days, indicative of stabilization and cell recovery after harvest. All cultures released H2O2 into the medium. Exposure to PM (20 μg/cm2) increased H2O2 levels significantly (94.6 ± 7.7 nM) compared to untreated controls (55.8 ± 4.0 nM; p = 0.001). PM‐induced H2O2 production was partially inhibited by DPI (80.1 ± 3.8nM), indicating that cellular NADPH oxidase may be a primary source of H2O2 production. Exposure to PM increased IL‐8 levels in a dose‐dependent fashion (control = 2301 ± 412 MFI; 20 μg/cm2 = 5002 ± 1327 MFI; 40 μg/cm2 = 8219 ± 1090 MFI; p = 0.022).

Conclusion

PM increases the quantity of H2O2 released by nasal epithelial cells, indicating that PM can contribute to oxidative stress in part by activating a normal cellular defense mechanism. Exposure to PM resulted in elevated IL‐8 levels and mucin production in explants. Efforts to reduce airborne PM may lead to reduced H2O2 and mucin production in sinonasal epithelium.
Integration of signal timing estimation model and dynamic traffic assignment in feedback loops: system design and case study
Authors: Zlatkovic Milan , Zhou Xuesong
Published: November 2014

This paper presents an integrated framework for effective coupling of a signal timing estimation model and dynamic traffic assignment (DTA) in feedback loops. There are many challenges in effectively integrating signal timing tools with DTA software systems, such as data availability, exchange format, and system coupling. In this research, a tight coupling between a DTA model with various queue‐based simulation models and a quick estimation method Excel‐based signal control tool is achieved and tested. The presented framework design offers an automated solution for providing realistic signal timing parameters and intersection movement capacity allocation, especially for future year scenarios. The framework was used to design an open‐source data hub for multi‐resolution modeling in analysis, modeling and simulation applications, in which a typical regional planning model can be quickly converted to microscopic traffic simulation and signal optimization models. The coupling design and feedback loops are first demonstrated on a simple network, and we examine the theoretically important questions on the number of iterations required for reaching stable solutions in feedback loops. As shown in our experiment, the current coupled application becomes stable after about 30 iterations, when the capacity and signal timing parameters can quickly converge, while DTA's route switching model predominately determines and typically requires more iterations to reach a stable condition. A real‐world work zone case study illustrates how this application can be used to assess impacts of road construction or traffic incident events that disrupt normal traffic operations and cause route switching on multiple analysis levels. Copyright © 2014 John Wiley & Sons, Ltd.
Assessment of human body influence on exposure measurements of electric field in indoor enclosures
Authors: de Miguel‐Bilbao Silvia , García Jorge , Ramos Victoria , Blas Juan
Published: November 2014

Personal exposure meters (PEMs) used for measuring exposure to electromagnetic fields (EMF) are typically used in epidemiological studies. As is well known, these measurement devices cause a perturbation of real EMF exposure levels due to the presence of the human body in the immediate proximity. This paper aims to model the alteration caused by the body shadow effect (BSE) in motion conditions and in indoor enclosures at the Wi‐Fi frequency of 2.4 GHz. For this purpose, simulation techniques based on ray‐tracing have been carried out, and their results have been verified experimentally. A good agreement exists between simulation and experimental results in terms of electric field (E‐field) levels, and taking into account the cumulative distribution function (CDF) of the spatial distribution of amplitude. The Kolmogorov–Smirnov (KS) test provides a P‐value greater than 0.05, in fact close to 1. It has been found that the influence of the presence of the human body can be characterized as an angle of shadow that depends on the dimensions of the indoor enclosure. The CDFs show that the E‐field levels in indoor conditions follow a lognormal distribution in the absence of the human body and under the influence of BSE. In conclusion, the perturbation caused by BSE in PEMs readings cannot be compensated for by correction factors. Although the mean value is well adjusted, BSE causes changes in CDF that would require improvements in measurement protocols and in the design of measuring devices to subsequently avoid systematic errors. Bioelectromagnetics. 36:118–132, 2015. © 2014 Wiley Periodicals, Inc.
Introns and gene expression: Cellular constraints, transcriptional regulation, and evolutionary consequences
Authors: Heyn Patricia , Kalinka Alex T. , Tomancak Pavel , Neugebauer Karla M.
Published: November 2014

A gene's “expression profile” denotes the number of transcripts present relative to all other transcripts. The overall rate of transcript production is determined by transcription and RNA processing rates. While the speed of elongating RNA polymerase II has been characterized for many different genes and organisms, gene‐architectural features – primarily the number and length of exons and introns – have recently emerged as important regulatory players. Several new studies indicate that rapidly cycling cells constrain gene‐architecture toward short genes with a few introns, allowing efficient expression during short cell cycles. In contrast, longer genes with long introns exhibit delayed expression, which can serve as timing mechanisms for patterning processes. These findings indicate that cell cycle constraints drive the evolution of gene‐architecture and shape the transcriptome of a given cell type. Furthermore, a tendency for short genes to be evolutionarily young hints at links between cellular constraints and the evolution of animal ontogeny.
Fluorescence quantum yield measurements of fluorescent proteins: A laboratory experiment for a biochemistry or molecular biophysics laboratory course
Authors: Wall Kathryn P. , Dillon Rebecca , Knowles Michelle K.
Published: November 2014

Fluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts absorbed photons into emitted photons and it is necessary to know for assessing what fluorescent protein is the most appropriate for a particular application. In this work, we have designed an upper‐level, biochemistry laboratory experiment where students measure the fluorescence quantum yields of fluorescent proteins relative to a standard organic dye. Four fluorescent protein variants, enhanced cyan fluorescent protein (ECFP), enhanced green fluorescent protein (EGFP), mCitrine, and mCherry, were used, however the methods described are useful for the characterization of any fluorescent protein or could be expanded to fluorescent quantum yield measurements of organic dye molecules. The laboratory is designed as a guided inquiry project and takes two, 4 hr laboratory periods. During the first day students design the experiment by selecting the excitation wavelength, choosing the standard, and determining the concentration needed for the quantum yield experiment that takes place in the second laboratory period. Overall, this laboratory provides students with a guided inquiry learning experience and introduces concepts of fluorescence biophysics into a biochemistry laboratory curriculum. © 2014 by The International Union of Biochemistry and Molecular Biology, 43(1):52–59, 2015.
Learning about solubility
Authors: Salinas Dino G. , Reyes Juan G.
Published: November 2014

Qualitative questions are proposed to assess the understanding of solubility and some of its applications. To improve those results, a simple quantitative problem on the precipitation of proteins is proposed. © 2014 by The International Union of Biochemistry and Molecular Biology, 43(1):3–5, 2015.
Stable suppression of myostatin gene expression in goat fetal fibroblast cells by lentiviral vector‐mediated RNAi
Authors: Patel Utsav A. , Patel Amrutlal K. , Joshi Chaitanya G.
Published: November 2014

Myostatin (MSTN) is a secreted growth factor that negatively regulates skeletal muscle mass, and therefore, strategies to block myostatin‐signaling pathway have been extensively pursued to increase the muscle mass in livestock. Here, we report a lentiviral vector‐based delivery of shRNA to disrupt myostatin expression into goat fetal fibroblasts (GFFs) that were commonly used as karyoplast donors in somatic‐cell nuclear transfer (SCNT) studies. Sh‐RNA positive cells were screened by puromycin selection. Using real‐time polymerase chain reaction (PCR), we demonstrated efficient knockdown of endogenous myostatin mRNA with 64% down‐regulation in sh2 shRNA‐treated GFF cells compared to GFF cells treated by control lentivirus without shRNA. Moreover, we have also demonstrated both the induction of interferon response and the expression of genes regulating myogenesis in GFF cells. The results indicate that myostatin‐targeting siRNA produced endogenously could efficiently down‐regulate myostatin expression. Therefore, targeted knockdown of the MSTN gene using lentivirus‐mediated shRNA transgenics would facilitate customized cell engineering, allowing potential use in the establishment of stable cell lines to produce genetically engineered animals. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:452–459, 2015
A Comprehensive Kinetic Study of the Reaction of SO2 with CaO by the Random Pore Model
Authors: Moshiri Hadi , Nasernejad Bahram , Ebrahim Habib Ale , Taheri Mahboobeh
Published: November 2014

The kinetics of the reaction between CaO and SO2 was studied by the random pore model, to accurately consider the porous structure of the solid reactant. The inherent reaction rate constants and rate dependency with respect to the SO2 concentration were determined from the initial slopes of the conversion‐time profiles obtained by thermogravimetry. A power law concentration dependency was applied and then the first‐order kinetics was verified. The product layer diffusivity was evaluated from the comparison of whole experimental conversion‐time profiles with the model predictions.
Nanopatterned Superlattices in Self‐Assembled C2‐Symmetric Oligodimethylsiloxane‐Based Benzene‐1,3,5‐Tricarboxamides
Authors: García‐Iglesias Miguel , de Waal Bas F. M. , de Feijter Isja , Palmans Anja R. A. , Meijer E. W.
Published: November 2014

The synthesis of C3‐ and C2‐symmetric benzene‐1,3,5‐tricarboxamides (BTAs) containing well‐defined oligodimethylsiloxane (oDMS) and/or alkyl side chains has been carried out. The influence of the bulkiness of the oDMS chains in the aggregation behavior of dilute solutions of the oDMS‐BTAs in methylcyclohexane was studied by temperature‐dependent UV spectroscopy. The formation of hierarchically self‐assembled aggregates was observed at different BTA concentrations, the tendency of aggregation increases by shortening or removing oDMS chains. Chiral BTAs were investigated with circular dichroism (CD) spectroscopy, showing a stronger tendency to aggregate than the achiral ones. Majority rules experiments show a linear behavior consistent with the existence of a high mismatch penalty energy. The most efficient oDMS‐BTAs organogelators have the ability to form stable organogels at 5 mg mL−1 (0.75 wt %) in hexane. Solid‐state characterization techniques indicate the formation of an intermolecular threefold hydrogen bonding between adjacent molecules forming thermotropic liquid crystals, exhibiting a hexagonal columnar organization from room temperature to above 150 °C. A decrease of the clearing temperatures was observed when increasing the number and length of the oligodimethylsiloxane chains. In addition to the three‐fold hydrogen bonding that leads to columnar liquid crystalline phase, segregation between the oDMS and aliphatic chains takes place in the BTA functionalized with two alkyl and one oDMS chain leading to a superlattice within the hexagonal structure with potential applications in lithography.
A Facile Top‐Down Protocol for Postsynthesis Modification of Hierarchical Aluminum‐Rich MFI Zeolites
Authors: Yu Lili , Huang Shengjun , Miao Shu , Chen Fucun , Zhang Shuang , Liu Zhenni , Xie Sujuan , Xu Longya
Published: November 2014

High aluminum content constitutes a major hurdle for the postsynthesis modification of hierarchical zeolites. A facile protocol comprising fluorination and sequential alkaline treatment is presented for the postsynthesis modification of hierarchical Al‐rich MFI zeolites. By virtue of this protocol, uniform intracrystalline mesoporosity is introduced in an Al‐rich MFI zeolite (Si/Al=14.3). The obtained hierarchical zeolites exhibit a significant mesopore size distribution, centered around 6 nm, and show improved conversions in catalytic cracking of bulky aromatic molecules. The fundamental implications of the fluorination–alkaline treatment protocol are related to the formation of F‐bearing tetrahedral aluminum species in the antecedent fluorination step, which alleviates the resistance of Al sites to the alkaline medium and causes AlF complexation for regulated hydrolysis of the Al species during the alkaline treatment process. This top‐down protocol and the derived mechanistic understandings are expected to be applied in the synthesis of hierarchical Al‐rich zeolites with other framework topologies.
Nanocomposites of Sulfonic Polyaniline Nanoarrays on Graphene Nanosheets with an Improved Supercapacitor Performance
Authors: Zhao Hai‐Bo , Yang Jun , Lin Ting‐Ting , Lü Qiu‐Feng , Chen Guo
Published: November 2014

A new nanocomposite, poly(aniline‐co‐diphenylamine‐4‐sulfonic acid)/graphene (PANISP/rGO), was prepared by means of an in situ oxidation copolymerization of aniline (ANI) with diphenylamine‐4‐sulfonic acid (SP) in the presence of graphene oxide, followed by the chemical reduction of graphene oxide using hydrazine hydrate as a reductant. The morphology and structure of PANISP/rGO were characterized by field‐emission (FE) SEM, TEM, X‐ray photoelectron spectroscopy (XPS), Raman, FTIR, and UV/Vis spectra. The electrochemical performance was evaluated by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The PANISP/rGO nanocomposite showed a nanosized structure, with sulfonic polyaniline nanoarrays coated homogeneously on the surface of graphene nanosheets. This special structure of the nanocomposite also facilitates the enhancement of the electrochemical performance of the electrodes. The PANISP/rGO nanocomposite exhibits a specific supercapacitance up to 1170 F g−1 at the current density of 0.5 A g−1. The as‐prepared electrodes show excellent supercapacitive performance because of the synergistic effects between graphene and the sulfonic polyaniline copolymer chains.
Differences and Comparisons of the Properties and Reactivities of Iron(III)–hydroperoxo Complexes with Saturated Coordination Sphere
Authors: Faponle Abayomi S. , Quesne Matthew G. , Sastri Chivukula V. , Banse Frédéric , de Visser Sam P.
Published: November 2014

Heme and nonheme monoxygenases and dioxygenases catalyze important oxygen atom transfer reactions to substrates in the body. It is now well established that the cytochrome P450 enzymes react through the formation of a high‐valent iron(IV)–oxo heme cation radical. Its precursor in the catalytic cycle, the iron(III)–hydroperoxo complex, was tested for catalytic activity and found to be a sluggish oxidant of hydroxylation, epoxidation and sulfoxidation reactions. In a recent twist of events, evidence has emerged of several nonheme iron(III)–hydroperoxo complexes that appear to react with substrates via oxygen atom transfer processes. Although it was not clear from these studies whether the iron(III)–hydroperoxo reacted directly with substrates or that an initial OO bond cleavage preceded the reaction. Clearly, the catalytic activity of heme and nonheme iron(III)–hydroperoxo complexes is substantially different, but the origins of this are still poorly understood and warrant a detailed analysis. In this work, an extensive computational analysis of aromatic hydroxylation by biomimetic nonheme and heme iron systems is presented, starting from an iron(III)–hydroperoxo complex with pentadentate ligand system (L52). Direct CO bond formation by an iron(III)–hydroperoxo complex is investigated, as well as the initial heterolytic and homolytic bond cleavage of the hydroperoxo group. The calculations show that [(L52)FeIII(OOH)]2+ should be able to initiate an aromatic hydroxylation process, although a low‐energy homolytic cleavage pathway is only slightly higher in energy. A detailed valence bond and thermochemical analysis rationalizes the differences in chemical reactivity of heme and nonheme iron(III)–hydroperoxo and show that the main reason for this particular nonheme complex to be reactive comes from the fact that they homolytically split the OO bond, whereas a heterolytic OO bond breaking in heme iron(III)–hydroperoxo is found.
Copper/Silver‐Mediated Direct ortho‐Ethynylation of Unactivated (Hetero)aryl CH Bonds with Terminal Alkyne
Authors: Liu Yue‐Jin , Liu Yan‐Hua , Yin Xue‐Song , Gu Wen‐Jia , Shi Bing‐Feng
Published: November 2014

A copper/silver‐mediated oxidative ortho‐ethynylation of unactivated aryl CH bonds with terminal alkyne has been developed. The reaction uses the removable PIP directing group and features broad substrate scope, high functional‐group tolerance, and compatibility with a wide range of heterocycles, providing an efficient synthesis of aryl alkynes. This procedure highlights the potential of copper catalysts to promote unique, synthetically enabling CH functionalization reactions that lie outside of the current scope of precious metal catalysis.
Applications of Lithium‐Containing Hydrides for Energy Storage and Conversion
Authors: Wietelmann Ulrich
Published: November 2014

Lithium‐containing hydrides and some derivatives are mainly used in synthetic chemistry for the selective reduction of functional groups. Hydrogen storage applications of complex Li hydrides and reactive mixtures with other metal hydrides or amides have been investigated thoroughly, but practical applications are hampered due to limited reversibility and unfavorable conditions for the sorption and desorption of hydrogen. In the field of electrochemical energy storage, complex Li‐containing hydrides are investigated as Li‐ion‐conducting materials and as active materials for anodes of non‐aqueous batteries.
Boosting Activation of Oxygen Molecules on C60 Fullerene by Boron Doping
Authors: Li Qiao‐Zhi , Zheng Jia‐Jia , Dang Jing‐Shuang , Zhao Xiang
Published: November 2014

The activation of oxygen molecules on boron‐doped C60 fullerene (C59B) and the subsequent water formation reaction are systematically investigated by using hybrid density functional calculations. Results indicate that C59B shows a favorable ability to activate oxygen molecules both kinetically and thermodynamically. The oxygen molecule is first adsorbed on the boron atom, which is identified to be the most reactive site in C59B for O2 adsorption because of its high positive charge and spin density. The adsorption structure C59BO2 can further isomerize to form two products with small reaction barriers. Water formation reactions upon these two structures are energetically favorable and suggest a four‐electron mechanism for the oxygen reduction reaction catalyzed by C59B. This work provides a reliable theoretical insight into the catalytic properties of boron‐doped fullerene, which is believed to be helpful to explore fullerene catalysts.
A Full Topological Analysis of Unstable and Metastable Bond Critical Points
Authors: Miorelli Jonathan , Wilson Tim , Morgenstern Amanda , Jones Travis , Eberhart Mark E.
Published: November 2014

Researchers are developing conceptually based models linking the structure and dynamics of molecular charge density to certain properties. Here we report on our efforts to identify features within the charge density that are indicative of instability and metastability. Towards this, we use our extensions to the quantum theory of atoms in molecules that capitalize on a molecule’s ridges to define a natural simplex over the charge density. The resulting simplicial complex can be represented at various levels by its 0‐, 1‐, and 2‐skeleton (dependent sets of points, lines, and surfaces). We show that the geometry of thesen‐skeletons retains critical information regarding the structure and stability of molecular systems while greatly simplifying charge density analysis. As an example, we use our methods to uncover the fingerprints of instability and metastability in two much‐discussed systems, that is, the di‐benzene complex and the He and adamantane inclusion complex.
Facile Synthesis of Hierarchical Magnesium Silicate Hollow Nanofibers Assembled by Nanosheets as an Efficient Adsorbent
Authors: Jin Renxi , Yang Yang , Li Yunfeng , Yu Xiaodan , Xing Yan , Song Shuyan , Shi Zhan
Published: November 2014

Magnesium silicate double‐walled hollow nanofibers (MSHNFs) with a hierarchical nanostructure have been successfully fabricated by combining the electrospinning technique with a hydrothermal method. The as‐prepared MSHNFs are composed of numerous ultrathin nanosheets with a thickness of approximately 10 nm and have a high specific surface area (632.2 m2 g−1) and large pore volume (0.92 cm3 g−1). The MSHNFs exhibit high adsorption capacity and excellent stability in a purification test with organic molecules and a solution of heavy‐metal ions. Moreover, the MSHNFs can be easily separated from solution by gravitational sedimentation owing to their unique structure.
Variable antenna‐space shift keying for high spectral efficiency in exponentially correlated channels
Authors: Osman Onur
Published: November 2014

In space shift keying (SSK), all information bits are transmitted by antenna indices rather than transmitting symbols. To obtain high spectral efficiency, exponentially increasing number of antennas is used, which is generally not practical. Less number of antennas can only be possible by using more than one active antenna, such as generalized SSK, but this type of solutions result in excessive degradation in bit error ratio in correlated channels. In this study, variable number of active antennas for each codeword is proposed and called variable antenna‐SSK. First of all, pairwise error probability is obtained for variable number of antennas in the case of correlated channels. Then, to reduce the correlation effect, a novel antenna codeword construction method that minimizes the pairwise error probability is introduced for exponentially correlated channels. Codeword sets are obtained for k = 3 and 8 bits/s/Hz for 7 and 13 transmit antennas. Simulation results show that variable antenna‐SSK gets better performance according to its counterparts with increasing effect of correlation. Copyright © 2014 John Wiley & Sons, Ltd.
Syntheses, Crystal Structures and Solid‐State Properties of the Lanthanoid‐Containing Nanoclusters [(Ln2PW10O38)4(W3O8)(OH)4(H2O)2]26–
Authors: Gupta Rakesh , Saini Mukesh Kumar , Hussain Firasat
Published: November 2014

A series of lanthanoid‐substituted polyoxometalates have been synthesized by a self‐assembly process in potassium chloride solution by the reaction of dilacunary [P2W19O69(H2O)]14– with mid‐ and late‐lanthanoid Ln(NO3)3·nH2O salts leading to the formation of the tetrameric tungstophosphates [(Ln2PW10O38)4(W3O8)(OH)4(H2O)2]26– [Ln = Y3+ (1), Sm3+ (2), Eu3+ (3), Gd3+ (4), Tb3+ (5), Dy3+ (6), Ho3+ (7), Er3+ (8), Tm3+ (9), Yb3+ (10)]. The polyanions were isolated as potassium or mixed‐alkali salts. Most of the compounds were characterized by single‐crystal X‐ray diffraction and various analytical techniques, such as FTIR, UV/Vis, 31P NMR and photoluminescence spectroscopy, magnetism, as well as thermogravimetric analysis. The FTIR spectra suggest that all the compounds are isomorphous. The crystal structures of these complexes consist of four A‐[α‐PW10O36]7– units, each incorporating two LnIII ions to create four Keggin‐like anions that further assemble with three additional tungstate units to form a tetramer species with C2 symmetry. The photoluminescent properties of 3a and 6a were investigated following photoexcitation at room temperature. The magnetic properties of 3a, 4a, 5a and 6a were investigated at room temperature, the complexes exhibiting paramagnetic behaviour.
Detection and Diagnosis of Various Contaminants in an Electroplating Bath by a Voltammetric Sensor: a Case Study
Authors: Jaworski Aleksander , Wikiel Hanna , Holverson Peter , Nelson Andrew , Wikiel Kazimierz
Published: November 2014

Chemical contamination cases encountered during semiconductor manufacturing which were resolved with the automated analytical system are described. The system is capable of collecting on‐line voltammetric data and investigating similarities between measurements at proper conditions and measurements with upset behaviour. The analytical system uses an in‐situ sensor employing voltammetric techniques providing a current response strongly affected by the presence of investigated disturbances (contamination with iron ions and with hydrogen peroxide). Soft Independent Modeling of Class Analogy (SIMCA) is a pattern recognition method which describes each class separately in eigenvector space. In this supervised classification technique the projected new measurements are evaluated aiming to determine whether they belong to certain class of disturbance or not. An assessment of the membership in a class of specific disturbance is a method of diagnosis whether such a disturbance affects the plating solution. The shape differences between deformed and reference set voltammograms are quantified by Mahalanobis Distance (MD)‐SIMCA. In addition to the numerical approach, a graphical projection is utilized to diagnose the root cause of the detected disturbances.
Porous Core‐Shell Platinum‐Silver Nanocatalyst for the Electrooxidation of Methanol
Authors: Singh Baljit , Seddon Brian , Dempsey Eithne , Redington Wynette , Dickinson Calum
Published: November 2014

A new class of platinum‐silver nanomaterial for the catalytic electrooxidation of methanol is considered here. The material was synthesised on a carbon nanochips platform via a combination of chemical reduction to form a particulate bimetallic alloy (Pt2Ag1/f‐CNC) and an anodic‐etching process to form a unique porous core‐shell platinum‐silver nanoparticle (np‐Pt2Ag1/f‐CNC). Morphology, structural and compositional characterisations of the alloy were performed using transmission electron microscopy (TEM), energy‐dispersive X‐ray spectrometry (EDX), thermogravimetric analysis (TGA) and X‐ray diffraction (XRD) techniques. Data confirms average particle size of 2.07 nm (median 1.73 nm). The alloy nature of the nanoparticle was confirmed by XRD and TEM/EDX analysis. The np‐Pt2Ag1/f‐CNC material was examined in electrochemical studies as a catalyst for the oxidation of methanol in sulfuric acid electrolyte. Catalytic efficiency is reported in terms of oxidation current density, 134.8 mA mg−1 (platinum mass) and a current ratio, If/Ib=0.86. The electrochemical data is indicative of high catalytic rates for methanol conversion, as well as the effectiveness of porous core‐shell platinum‐silver particles to resist carbon monoxide poisoning. The work demonstrates improved long‐term catalytic performance of a novel nanomaterial electrode offering promising energy applications.
Proteome profiling of keratinocytes transforming to malignancy
Authors: Paulitschke Verena , Gerner Christopher , Hofstätter Elisabeth , Mohr Thomas , Mayer Rupert Laurenz , Pehamberger Hubert , Kunstfeld Rainer
Published: November 2014

To shed light on the multistep process of squamous cell carcinoma development and the underlying pathologic mechanisms, we performed comparative proteome analysis of keratinocytes, keratinocytes stimulated with Il‐1beta, and A431 epidermoid carcinoma cells. Fractionation of the cells into supernatant, nucleus, and cytoplasm was followed by protein separation, proteolytic digest, and nano‐LC separation, and fragmentation using an ion trap mass spectrometer. Specific bioinformatics tools were used to generate a list of keratinocyte‐specific proteins. Ninety percent of these proteins were found to be upregulated in keratinocytes versus the A431 cells. Classification of the identified proteins by biologic function and gene set enrichment analysis revealed that keratinocytes produced more proteins involved in cell differentiation, cell adhesion, cell junction, calcium ion, calmodulin binding, cytoskeleton organization, and cytokinesis, whereas A431 produced more proteins involved in cell cycle checkpoint, cell cycle process, RNA processing and transport, DNA damage and repair, RNA and DNA binding, and chromatin remodeling. The protein signatures of A431 and normal keratinocytes treated with IL‐1beta showed marked similarity, confirming that inflammation is an important step in malignant transformation in nonmelanoma skin cancer. Thus, proteome profiling and bioinformatic processing may support the understanding of the underlying mechanisms, with the potential to facilitate development of early biomarkers and patient‐tailored therapy.
Gold nanomaterials based pseudostationary phases in capillary electrophoresis: A brand‐new attempt at chondroitin sulfate isomers separation
Authors: Zhao Ting , Zhou Guanglian , Wu Yuanhong , Liu Xiumei , Wang Fengshan
Published: November 2014

In this work, a CE method with bare gold nanorods (GNRs) based pseudostationary phase was developed and applied for the separation of chondroitin sulfate (CS) isomers, CS, and dermatan sulfate (DS). The separation efficiency was investigated by varying the experimental parameters such as concentration and pH of the BGE, separation voltage, internal diameter of capillary, different size, and morphology of gold nanomaterials. Results showed that different size and morphology of gold nanomaterials had different effects on the separation of CS and DS. The best separation of CS and DS was achieved in the BGE composed of aqueous 150 mmol/L (mM) ethylenediamine + 20 mM sodium dihydrogen phosphate + 30% v/v GNRs, pH 4.5, at the separation voltage of −10 kV. Capillary was 59.2 cm in length (effective length 49 cm), 50 μm id capillary thermostated at 25°C. CE with bare GNRs used as pseudostationary phase was shown to be a suitable technique for the separation of CS and DS mixtures with wider peaks. RSD of migration time and peak area of CS and DS were 0.13, 0.14 and 0.86, 1.07%, respectively.
Effect of gravity framing on the overstrength and collapse capacity of steel frame buildings with perimeter special moment frames
Authors: Elkady Ahmed , Lignos Dimitrios G.
Published: November 2014

This paper investigates the effect of the gravity framing system on the overstrength and collapse risk of steel frame buildings with perimeter special moment frames (SMFs) designed in North America. A nonlinear analytical model that simulates the pinched hysteretic response of typical shear tab connections is calibrated with past experimental data. The proposed modeling approach is implemented into nonlinear analytical models of archetype steel buildings with different heights. It is found that when the gravity framing is considered as part of the analytical model, the overall base shear strength of steel frame buildings with perimeter SMFs could be 50% larger than that of the bare SMFs. This is attributed to the gravity framing as well as the composite action provided by the concrete slab. The same analytical models (i) achieve a static overstrength factor,Ωslarger than 3.0 and (ii) pass the collapse risk evaluation criteria by FEMA P695 regardless of the assigned total system uncertainty. However, when more precise collapse metrics are considered for collapse risk assessment of steel frame buildings with perimeter SMFs, a tolerable probability of collapse is only achieved in a return period of 50 years when the perimeter SMFs of mid‐rise steel buildings are designed with a strong‐column/weak‐beam ratio larger than 1.5. The concept of the dynamic overstrength,Ωdis introduced that captures the inelastic force redistribution due to dynamic loading. Steel frame buildings with perimeter SMFs achieve aΩd > 3 regardless if the gravity framing is considered as part of the nonlinear analytical model representation. Copyright © 2014 John Wiley & Sons, Ltd.
Global challenges in agriculture and the World Bank's response in Africa
Authors: Saghir Jamal
Published: November 2014

A country's economic, environmental and social well‐being is intricately linked to a healthy, well‐performing agricultural sector. Across Africa, south of the Sahara, agriculture is the predominant sector in the economies of most countries accounting for between 30 to 40 percent of gross domestic product, and the sector is a leading source of jobs for over two‐thirds of Africa's population. With an abundance of labor, land and untapped water, Sub‐Saharan Africa has the resources necessary for a massive expansion of agricultural production. Notwithstanding these advantages, over the last 40 years Africa has been steadily losing its share of the global agricultural market. Today, Thailand exports more food products than all of Sub‐Saharan Africa combined. The “Green Revolution” that transformed tropical agriculture in Asia and Latin America largely bypassed Africa. A confluence of factors – increasing prices for African agricultural products, booming urban food markets, many opportunities for expanding irrigated area, greater interest by development partners, improved policy environment, technological innovations, rising private sector interest, framework for climate‐smart agriculture, and improved infrastructure – present a golden opportunity for African agriculture to realize its full potential. Responding to the challenges, the World Bank is scaling up its support for African agriculture. The medium‐term plan is to scale up lending to US$3 billion a year, with ambitious targets in key thematic areas – irrigation, land administration, access to technology, inputs, financial services and markets, and climate‐smart agriculture – so that Sub‐Saharan Africa can benefit fully from the transformative opportunity. Greater South‐South learning and collaboration, and strengthening of African institutions and building capacity are all needed. Agriculture is the pathway to ending poverty and boosting shared prosperity in Sub‐Saharan Africa, backed by improvements in education, health, nutrition and sustainable management of natural resources among others. The prospects for success have never been better.
Comparison of implicit and explicit AUSM‐family schemes for compressible multiphase flows
Authors: Zeng Q. L. , Aydemir N. U. , Lien F. S. , Xu T.
Published: November 2014

This paper makes the first attempt of extending implicit AUSM‐family schemes to multiphase flow simulations. Water faucet, air–water shock tube and oscillating manometer problems are used as benchmark tests with the generic four‐equation two‐fluid model. For solving the equations implicitly, Newton's method along with a sparse matrix solver (UMFPACK solver) is employed, and the numerical Jacobian matrix is calculated. Comparison between implicit and explicit AUSM‐family schemes is presented, indicating that similarly accurate results are obtained with both schemes. Furthermore, the water faucet problem is solved using both staggered and collocated grids. This investigation helps integrate high‐resolution schemes into staggered‐grid‐based computational algorithms. The influence of the interface pressure correction on the simulation results is also examined. Results show that the interfacial pressure correction introduces numerical dissipation. However, this dissipation cannot eliminate the overshoots because of the incompatibility of numerical discretization of the conservative and non‐conservative terms in the governing equations. The comparison of CPU time between implicit and explicit schemes is also studied, indicating that the implicit scheme is capable of improving the computational efficiency over its explicit counterpart. Copyright © 2014 John Wiley & Sons, Ltd.
Development and nutritional and sensory evaluation of cachapinta (Pseudoplatystoma sp) pâté
Authors: Lobo Cátia Maria de Oliveira , Torrezan Renata , de Furtado Ângela Aparecida Lemos , Antoniassi Rosemar , Freitas Daniela De Grandi Castro , de Freitas Sidinéa Cordeiro , Penteado Ana Lúcia , de Oliveira Cássia Soares , Junior Carlos Adam Conte , Mársico Eliane Teixeira
Published: November 2014

This study developed a technique for the preparation of pâté from cachapinta (Pseudoplatystoma sp) waste. For this, frozen minced cachapinta fish was crushed in a mini cutter and homogenized with all other ingredients. The prepared pâté was stored in seamed and thermally treated cans (volume 170 g). Weight proportions of mean moisture, ash, protein, and lipid contents of the minced fish were 75.49, 1.00, 15.00, and 7.92 (g/100 g), respectively. The formulation of the developed pâté is in accordance with legislation for fish products. Cachapinta pâté is a product with high content of polyunsaturated fatty acids, low level of trans fat, and good indices of nutritional quality. Tests of sensory acceptance, purchase intent, and sensory attributes (except spreadability) averaged a score above 6.0, indicating acceptability of the product. Our study suggests that the potential of minced cachapinta for pâté production is high, and that it can contribute a value‐added product to seafood consumption.
Structural and functional correlates of behavioral pattern separation in the hippocampus and medial temporal lobe
Authors: Doxey Christopher R. , Kirwan C. Brock
Published: November 2014

Structures of the medial temporal lobe (MTL) are known to be involved in declarative memory processes. However, little is known about how age‐related changes in MTL structures, white matter integrity, and functional connectivity affect pattern separation processes in the MTL. In this study, we used magnetic resonance imaging (MRI) to measure the volumes of MTL regions of interest, including hippocampal subfields (dentate gyrus, CA3, CA1, and subiculum) in healthy older and younger adults. Additionally, we used diffusion tensor imaging to measure white matter integrity for both groups. Finally, we used functional MRI to acquire resting functional connectivity measures for both groups. We show that, along with age, the volume of left CA3/dentate gyrus predicts memory performance. Differences in fractional anisotropy and the strength of resting functional connections between the hippocampus and other cortical structures implicated in memory processing were not significant predictors of performance. As previous studies have only hinted, it seems that the size of left CA3/dentate gyrus contributes more to successful discrimination between similar mnemonic representations than other hippocampal sub‐fields, MTL structures, and other neuroimaging correlates. Accordingly, the implications of aging and atrophy on lure discrimination capacities are discussed. © 2014 Wiley Periodicals, Inc.
Groundwater ‐ the disregarded component in lake water and nutrient budgets. Part 1: effects of groundwater on hydrology
Authors: Rosenberry Donald O. , Lewandowski Jörg , Meinikmann Karin , Nützmann Gunnar
Published: November 2014

Lake eutrophication is a large and growing problem in many parts of the world, commonly due to anthropogenic sources of nutrients. Improved quantification of nutrient inputs is required to address this problem, including better determination of exchanges between groundwater and lakes. This first of a two‐part review provides a brief history of the evolution of the study of groundwater exchange with lakes, followed by a listing of the most commonly used methods for quantifying this exchange. Rates of exchange between lakes and groundwater compiled from the literature are statistically summarized for both exfiltration (flow from groundwater to a lake) and infiltration (flow from a lake to groundwater), including per cent contribution of groundwater to lake‐water budgets. Reported rates of exchange between groundwater and lakes span more than five orders of magnitude. Median exfiltration is 0.74 cm/day, and median infiltration is 0.60 cm/day. Exfiltration ranges from near 0% to 94% of input terms in lake‐water budgets, and infiltration ranges from near 0% to 91% of loss terms. Median values for exfiltration and infiltration as percentages of input and loss terms of lake‐water budgets are 25% and 35%, respectively. Quantification of the groundwater term is somewhat method dependent, indicating that calculating the groundwater component with multiple methods can provide a better understanding of the accuracy of estimates. The importance of exfiltration to a lake budget ranges widely for lakes less than about 100 ha in area but generally decreases with increasing lake area, particularly for lakes that exceed 100 ha in area. No such relation is evident for lakes where infiltration occurs, perhaps because of the smaller sample size. Copyright © 2014 John Wiley & Sons, Ltd.
Association between adult weight gain and colorectal cancer: A dose–response meta‐analysis of observational studies
Authors: Chen Qi , Wang Jing , Yang Jinghui , Jin Zhichao , Shi Wentao , Qin Yingyi , Yu Feifei , He Jia
Published: November 2014

This study investigated the association between adult weight gain and risk of colorectal cancer (CRC). Using terms related to weight gain and CRC, we searched PubMed, Embase and Web of Science for relevant studies published before June 2014. Two evaluators independently selected studies according to the selection criteria, and eight studies were included (three case–control and five cohort studies). Summary estimates were obtained using fixed‐ or random‐effects models. The relative risk (RR) of the association between adult weight gain and CRC was 1.25 (95% confidence interval [CI], 1.10–1.43); the RR was 1.30 (95% CI, 1.14–1.49) for colon cancer (CC) and 1.27 (95% CI, 1.02–1.58) for rectal cancer (RC) for the highest versus lowest category. For every 5‐kg increase in adult weight, the risk increased by 5% (RR, 1.05; 95% CI, 1.02–1.09) for CRC, 6% (RR, 1.06; 95% CI, 1.02–1.11) for CC and 6% (RR, 1.06; 95% CI, 1.03–1.08) for RC. The subgroup analyses showed a positive association between adult weight gain and risk of CRC only in men, and the RR was 1.65 (95% CI, 1.42–1.92) for the highest versus lowest category of adult weight gain and 1.10 (95% CI, 1.06–1.15) for a 5‐kg increase in adult weight. In conclusion, there is evidence that adult weight gain is associated with an increased risk of CRC. However, the positive association between adult weight gain and risk of CRC is stronger among men than among women.
Identifying specialisation, production and exchange in the archaeological record: the case of shell bead manufacture on Motupore Island, Papua
Authors: Allen Jim , Holdaway Simon , Fullagar Richard
Published: November 2014

Analyses of shell beads and stone drillpoints from Motupore Island, near Port Moresby, PNG contribute to the debate about the specialised role of the site in a prehistoric exchange network as well as to theoretical discussions concerning the relationship between craft specialisation and social stratification. The presence of drillpoints, which are specialised and efficient tools for making beads, demonstrates a level of technological efficiency expected with trading systems. Studies of the spatial patterning of drillpoints, shell beads, and grinding slabs on the site and in the region, along with usewear and residue research, and statistical analyses of the artifacts are carried out. These data demonstrate that shell bead manufacture represents village level craft specialisation and was a significant part of Motupore's economy throughout its history. Finally, the paper shows that village level specialised production need not imply institutionalised social differentiation.
Changes in Admiralty Islands obsidian source use: the view from Pamwak
Authors: Fredericksen Clayton
Published: November 2014

I report the results of characterisation analysis of obsidian from Pamwak shelter on Manus in the Admiralty Islands (Papua New Guinea). Evidence is presented that the first transport of obsidian to the shelter occurred in the terminal Pleistocene, probably from an offshore source. A mid Holocene change to the use of predominantly Pam Islands obsidian is noted. The use of significant amounts of Lou obsidian, a material widely used and traded after 3500 BP, is identified as occurring only late in the sequence. The implications of these changes in the context of Wal Ambrose's research are discussed.
Sociality and the short distance trader: intra‐regional obsidian exchange in the Willaumez region, Papua New Guinea
Authors: Torrence Robin , Summerhayes Glenn R.
Published: November 2014

An analysis of changes in the assemblage composition of obsidian from different sources was undertaken on 12 assemblages from sites dating over the past 6,000 years in the Willaumez region (including the peninsula and nearby islands) in West New Britain, in order to investigate Ambrose's (1978) prediction that Lapita obsidian trade differed from recent ethnographic systems. The history of obsidian use on Garua Island, where sites contain various mixes of local and imported obsidian, points to the existence of an intra‐regional system of exchange between communities specialising in one or more goods during the time of Lapita pottery (c. 3,500–2,000 BP). The method of obsidian procurement is shown to have been significantly different from both the earlier and later phases. It is argued that the widespread distribution of obsidian on Lapita sites in both Near and Remote Oceania is the result of movement between a loosely integrated series of local, intra‐regional systems and not long‐distance trade over the entire area as proposed by previous scholars.