bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal and rheological properties of polyethylene blends with bimodal molecular weight distribution
Authors: Shen Hong‐Wang , Xie Bang‐Hu , Yang Wei , Yang Ming‐Bo
Published: January 2013

Polyethylene blends with bimodal molecular weight distribution were prepared by blending a high molecular weight polyethylene and a low molecular weight polyethylene in different ratios in xylene solution. The blends and their components were characterized by the high temperature gel permeation chromatograph (GPC), different scanning calorimetry (DSC), and small amplitude oscillatory shear experiments. The results showed that the dependence of zero‐shear viscosity (η0) on molecular weight followed a power law equation with an exponent of 3.3. The correlations between characteristic frequency (ω0) and polydispersity index, and between dynamic cross‐point (Gx) and polydispersity index were established. The complex viscosity (η*) at different frequencies followed the log‐additivity rule, and the Han‐plots were independent of component and temperature, which indicated that the HMW/LMW blends were miscible in the melt state. Moreover, the thermal properties were very similar to a single component system, suggesting that the blends were miscible in the crystalline state. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Enhancement of fibroblastic proliferation from photoreactive starch with immobilized epidermal growth factor
Authors: Cho Young‐Min , Lee Hyung‐Jae , Heo Yun , Park Shin‐Hye , Seo Si‐Yoong , Han Jae‐Hong , Son Tae‐Il
Published: January 2013

Carboxymethyl starch was modified by the incorporation of an azidophenyl group to prepare photoreactive starch, and characterized by Fourier transform infrared reflectance (FT‐IR), proton nuclear magnetic resonance (1H‐NMR), and ultraviolet (UV) spectroscopy. Photo‐irradiation immobilized the Az‐starch on a polystyrene plate and it was stably retained on the surface. The protein containing immobilized Az‐starch was also immobilized on a stripe micropatterned plate. UV irradiation time and Az‐starch concentration were used to alter the physical properties of Az‐starch and consequently control the rate of epidermal growth factor (EGF) release. The Az‐starch that released growth factor was not cytotoxic to 3T3‐L1 fibroblast cells, and the immobilized EGF maintained its activity and induced cellular proliferation in vitro. These results suggest that Az‐starch could be useful as a clinical synthetic material for medical applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Development of active barrier systems for poly(ethylene terephthalate)
Authors: Mahajan Kamal , Lofgren Elizabeth A. , Jabarin Saleh A.
Published: January 2013

Copolymers of Poly(ethylene terephthalate) (PET) were synthesized by the melt polymerization of terephthalic acid (TPA) with ethylene glycol (EG) and with each of the active oxygen scavengers; monoolein (MO) and 3‐cyclohexene‐1,1‐dimethanol (CHEDM) in separate compositions. Proton nuclear magnetic resonance spectroscopy (1H NMR) and 2D correlation spectroscopy (COSY) indicated that PET had reacted with both MO and CHEDM at their hydroxyl end groups. Oxygen barrier properties of the MO and CHEDM copolymers exhibited improvements of up to 40%, in comparison to an unmodified commercial PET. Effects of the oxygen scavengers on the copolymers' physical properties were investigated in terms of their crystallization, melting, and rheological behaviors. Both types of copolymers showed decreases in peak melting temperatures with increased scavenger concentrations and also crystallized more slowly as the scavenger concentrations increased. The PET/MO copolymer showed non‐Newtonian rheological behavior with higher MO concentration; while the PET/CHEDM copolymers showed Newtonian behavior within the studied range of CHEDM concentrations. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The impact of technological advances on recording studio practices
Authors: Pras Amandine , Guastavino Catherine , Lavoie Maryse
Published: January 2013

Since the invention of sound reproduction in the late 19th century, studio practices in musical recording evolved in parallel with technological improvements. Recently, digital technology and Internet file sharing led to the delocalization of professional recording studios and the decline of traditional record companies. A direct consequence of this new paradigm is that studio professions found themselves in a transitional phase, needing to be reinvented. To understand the scope of these recent technological advances, we first offer an overview of musical recording culture and history and show how studio recordings became a sophisticated form of musical artwork that differed from concert representations. We then trace the economic evolution of the recording industry through technological advances and present positive and negative impacts of the decline of the traditional business model on studio practices and professions. Finally, we report findings from interviews with six world‐renowned record producers reflecting on their recording approaches, the impact of recent technological advances on their careers, and the future of their profession. Interviewees appreciate working on a wider variety of projects than they have in the past, but they all discuss trade‐offs between artistic expectations and budget constraints in the current paradigm. Our investigations converge to show that studio professionals have adjusted their working settings to the new economic situation, although they still rely on the same aesthetic approaches as in the traditional business model to produce musical recordings.
A Bounded Real Lemma for Discrete‐Time Markovian Jump Singular Systems
Authors: Wei Jumei , Ma Rui , Mu Xiaowu
Published: January 2013

This paper presents a bounded real lemma for discrete‐time Markovian jump singular systems. First, a new necessary and sufficient condition is proposed in terms of a strict linear matrix inequality, which guarantees the stochastic admissibility of the unforced Markovian jump singular systems. Then, a bounded real lemma for discrete‐time Markovian jump singular systems is derived. It is also proven that the bounded real lemma can be described by a strict matrix inequality. Finally, a numerical example is provided to illustrate the effectiveness of the proposed theory. The results are more tractable and reliable in numerical computations than existing conditions.
Synthesis and characterization of blue long‐lasting BaCa2Al8O15:Eu2+, Dy3+ phosphor
Authors: Yerpude A. N. , Dhoble S. J. , Haranath D.
Published: January 2013

We have synthesized and characterized a new BaCa2Al8O15:Eu2+,Dy3+ phosphor prepared by the combustion method. X‐ray diffraction, thermoluminescence, scanning electron microscope, time decay and optical spectral analysis photoluminescence excitation, emission spectra were used to characterize the phosphors. Broadband ultraviolet excited luminescence of the BaCa2Al8O15:Eu2+,Dy3+ was observed in the blue region (λmax = 435 nm) due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. Scanning electron microscopy has been used for exploring the morphological properties of the prepared phosphors. The BaCa2Al8O15:Eu2+ phosphor has a blue afterglow when Dy3+ ions were co‐doped. The thermoluminescence spectra show that the Dy3+ ion induces a proper trap in the phosphor with a depth of 0.67 eV and results in a long afterglow phosphorescence. Copyright © 2013 John Wiley & Sons, Ltd.
In vitro and in vivo studies disclosed the depigmenting effects of gallic acid: A novel skin lightening agent for hyperpigmentary skin diseases
Authors: Kumar K. J. Senthil , Vani M. Gokila , Wang Sheng‐Yang , Liao Jiunn‐Wang , Hsu Li‐Sung , Yang Hsin‐Ling , Hseu You‐Cheng
Published: January 2013

Gallic acid (GA) is a phenolic compound, which has been reported to suppress melanogenesis in melanoma cells. However, the molecular mechanism underlying this inhibitory effect was poorly understood. In this article, we revealed that GA down‐regulated melanogenic regulatory genes including tyrosinase, tyrosinase related protein‐1 (TRP‐1), and dopachrome tatamerase (Dct) expression at transcriptional and translational level. In addition, GA effectively suppressed the microphthalmia‐associated transcription factor (MITF) expression by down‐regulating the cAMP‐mediated PKA/CREB signaling cascades. To delineate the inhibition of MITF by GA, the activation of extracellular signal‐regulated protein kinase (ERK) and AKT was investigated. GA caused significant increase of ERK and AKT phosphorylation, while ERK (PD98059) or AKT (LY294002) inhibitor prevents their phosphorylation and increased melanin biosynthesis. In addition, pre‐treatment of MITF‐siRNA significantly reduced melanin production from 100 to 40%, and even decreased into 10% by combination treatment with GA. Furthermore, UVB‐induced hyperpigmentation in the mice skin was significantly rescued by topical application of GA for 4 weeks. Immunohistochemical analyses also confirmed that GA significantly inhibited melanin production followed by the down‐regulation of MITF, tyrosinase and their regulatory proteins. In addition, when compared with control zebrafish, GA caused a remarkable inhibition on the endogenous pigmentation in the zebrafish. Results presented in this study strongly suggest that GA is an effective de‐pigmenting or skin lightening cosmetics for topical application. © 2012 BioFactors, 2013
Classification Accuracy of Actuarial Risk Assessment Instruments
Authors: Neller Daniel J. , Frederick Richard I.
Published: January 2013

Users of commonly employed actuarial risk assessment instruments (ARAIs) hope to generate numerical probability statements about risk; however, ARAI manuals often do not explicitly report data that are essential for understanding the classification accuracy of the instruments. In addition, ARAI manuals often contain data that have the potential for misinterpretation. The authors of the present article address the accurate generation of probability statements. First, they illustrate how the reporting of numerical probability statements based on proportions rather than predictive values can mislead users of ARAIs. Next, they report essential test characteristics that, to date, have gone largely unreported in ARAI manuals. Then they discuss a graphing method that can enhance the practice of clinicians who communicate risk via numerical probability statements. After the authors review several strategies for selecting optimal cut‐off scores, they show how the graphing method can be used to estimate positive predictive values for each cut‐off score of commonly used ARAIs, across all possible base rates. They also show how the graphing method can be used to estimate base rates of violent recidivism in local samples. Copyright © 2013 John Wiley & Sons, Ltd.
Caged CO2 for the Direct Observation of CO2‐Consuming Reactions
Authors: Lommel Katharina , Schäfer Gabriela , Grenader Konstantin , Ruland Christoph , Terfort Andreas , Mäntele Werner , Wille Georg
Published: January 2013

CO2‐consuming reactions, in particular carboxylations, play important roles in technical processes and in nature. Their kinetic behavior and the reaction mechanisms of carboxylating enzymes are difficult to study because CO2 is inconvenient to handle as a gas, exists in equilibrium with bicarbonate in aqueous solution, and typically yields products that show no significant spectroscopic differences from the reactants in the UV/Vis range. Here we demonstrate the utility of 3‐nitrophenylacetic acid and related compounds (caged CO2) in conjunction with infrared spectroscopy as widely applicable tools for the investigation of such reactions, permitting convenient measurement of the kinetics of CO2 consumption. The use of isotopically labeled caged CO2 provides a tool for the assignment of infrared absorption bands, thus aiding insight into reaction intermediates and mechanisms.
Stable and Efficient Pt–Re/TiO2 catalysts for Water‐Gas‐Shift: On the Effect of Rhenium
Authors: Azzam Khalid G. , Babich Igor V. , Seshan Kulathuiyer , Mojet Barbara L. , Lefferts Leon
Published: January 2013

The catalytic performance of Pt–Re/TiO2 catalysts, that is, activity and stability, in single‐stage water gas shift reactions was investigated by studying the influence of preparation strategies, Pt/Re molar ratios, and metals contents. Results show that sequential impregnation of Re precursor prior to Pt precursor without intermediate pretreatment is the optimum preparation strategy. The Pt/Re ratio of unity with 0.5 wt. % Pt content resulted in the most significant effect on activity and stability. In situ characterizing of both monometallic and the optimal bimetallic Pt–Re catalysts by means of CO chemisorption, H2 temperature programmed reduction, and FTIR spectroscopy under the reaction conditions provided evidence that Re increases the activity by enhancing the activation of water. No evidence was found for any direct influence of Re on the properties of Pt in the catalyst under the reaction conditions.
Effects of Support, Particle Size, and Process Parameters on Co3O4 Catalyzed H2O Oxidation Mediated by the [Ru(bpy)3]2+ Persulfate System
Authors: Yang Chieh‐Chao , Eggenhuisen Tamara M. , Wolters Mariska , Agiral Anil , Frei Heinz , de Jongh Petra E. , de Jong Krijn P. , Mul Guido
Published: January 2013

Water oxidation over highly dispersed cobalt oxide particles in porous silica was studied, applying photo‐activation of the Ru(bpy)32+ photosensitizer complex and the sacrificial electron acceptor (S2O82−). Under identical process conditions, 4 nm crystalline Co3O4 particles dispersed in SBA‐15, obtained by calcination of impregnated Co(NO3)2 in an NO/N2 atmosphere, showed higher O2 evolution rates than 7 nm Co3O4 particles, obtained by air calcination of the same catalyst precursor. A similar trend was observed for Co3O4 dispersed in MCM‐41, although MCM‐41 catalysts showed lower O2 production rates than SBA‐15 catalysts of comparable Co3O4 sizes. The positive effect of a small Co3O4‐particle size is related to the higher amount of surface sites of Co3O4 interacting with the Ru complex, which subsequently leads to water oxidation. The effect of the silica scaffold was demonstrated to be the result of the higher surface area of MCM‐41 versus SBA‐15 (≈1000 m2 g−1 versus 600 m2 g−1). Consequently a larger fraction of the [Ru(bpy)3]2+ photosensitizer complex immobilizes on the silica walls, and thus becomes ineffective to stimulate water oxidation. The nanosized Co3O4 particles in general were more effective than previously reported micron‐sized crystals, even though nanostructuring leads to less favorable optical properties of Co3O4. The stability of the used Ru(bpy)32+ sensitizer, which is a function of mode of irradiation (wavelength) and buffer capacity, was found to be a major factor in controlling the evolved oxygen quantity.
Remarkable Reinforcement of a Supramolecular Gel Constructed by Heteroditopic [18]Crown‐6‐Based Molecular Recognition
Authors: Noh Eunyoung , Park Sunhong , Kang Sunwoo , Lee Jin Yong , Jung Jong Hwa
Published: January 2013

The heteroditopic crown ether‐based ligand 1 containing the diazafluorenylimino group as a binding site for the Zn2+ and Cs+ was synthesized. The ligand 1 can be gelated in DMSO/water with and without Cs+ in the presence of the Zn2+ ion. Interestingly, the remarkable gelation reinforcement of gel 1 occurred with Cs+ in the presence of Zn2+, which is due to the formation of a sandwich complex. According to DFT calculations, one Zn2+ is bound to two diazafluorenylimino moieties in a tetrahedral structure. In addition, one Cs+ ion is bound to two crown‐rings. The Zn2+‐diazafluorenylimino ligand gel without Cs+ shows a spherical structure with 250–800 nm diameter, whereas the Zn2+‐diazafluorenylimino‐based ligand gel with Cs+ shows a fiber structure with 60–70 nm diameter and several micrometers of lengths. The rheological properties of the Zn2+‐ diazafluorenylimino‐based ligand gel were strongly dependent on the presence of Cs+.
Luminescent Coordination Polymers Based on Self‐Assembled Cadmium Dipyrrin Complexes
Authors: Béziau Antoine , Baudron Stéphane A. , Guenet Aurélie , Hosseini Mir Wais
Published: January 2013

A series of novel CdII complexes based on α,β‐unsubstituted dipyrrin ligands (dpm) has been prepared and characterised both in solution and in the solid state. These compounds are of the [Cd(dpm)2] type, with the coordination sphere of the metal centre occupied by two dpm chelates. Interestingly, in contrast to what has been reported for the ZnII analogues, in the presence of a pyridyl‐ or imidazolyl‐appended dpm ligand, the coordination number of the CdII cation can be increased to six, leading to an octahedral coordination sphere. As a consequence, the formation of 1‐, 2‐, and 3D coordination polymers by self‐assembly is observed. Photophysical investigations of the discrete complexes and self‐assembled networks have demonstrated that both types of compounds are luminescent in the solid state.
Polysulfide Chemistry in Sodium–Sulfur Batteries and Related Systems— A Computational Study by G3X(MP2) and PCM Calculations
Authors: Steudel Ralf , Steudel Yana
Published: January 2013

The sodium–sulfur (NAS) battery is a candidate for energy storage and load leveling in power systems, by using the reversible reduction of elemental sulfur by sodium metal to give a liquid mixture of polysulfides (Na2Sn) at approximately 320 °C. We investigated a large number of reactions possibly occurring in such sodium polysulfide melts by using density functional calculations at the G3X(MP2)/B3LYP/6‐31+G(2df,p) level of theory including polarizable continuum model (PCM) corrections for two polarizable phases, to obtain geometric and, for the first time, thermodynamic data for the liquid sodium–sulfur system. Novel reaction sequences for the electrochemical reduction of elemental sulfur are proposed on the basis of their Gibbs reaction energies. We suggest that the primary reduction product of S8 is the radical anion ${{\rm S}{{{{\bullet}}- \hfill \atop 8\hfill}}}$, which decomposes at the operating temperature of NAS batteries exergonically to the radicals ${{\rm S}{{{{\bullet}}- \hfill \atop 2\hfill}}}$ and ${{\rm S}{{{{\bullet}}- \hfill \atop 3\hfill}}}$ together with the neutral species S6 and S5, respectively. In addition, ${{\rm S}{{{{\bullet}}- \hfill \atop 8\hfill}}}$ is predicted to disproportionate exergonically to S8 and ${{\rm S}{{2- \hfill \atop 8\hfill}}}$ followed by the dissociation of the latter into two ${{\rm S}{{{{\bullet}}- \hfill \atop 4\hfill}}}$ radical ions. By recombination reactions of these radicals various polysulfide dianions can in principle be formed. However, polysulfide dianions larger than ${{\rm S}{{2- \hfill \atop 4\hfill}}}$ are thermally unstable at 320 °C and smaller dianions as well as radical monoanions dominate in Na2Sn (n=2–5) melts instead. The reverse reactions are predicted to take place when the NAS battery is charged. We show that ion pairs of the types ${{\rm NaS}{{{{\bullet}}\hfill \atop 2\hfill}}}$, ${{\rm NaS}{{- \hfill \atop n\hfill}}}$, and Na2Sn can be expected at least for n=2 and 3 in NAS batteries, but are unlikely in aqueous sodium polysulfide except at high concentrations. The structures of such radicals and anions with up to nine sulfur atoms are reported, because they are predicted to play a key role in the electrochemical reduction process. A large number of isomerization, disproportionation, and sulfurization reactions of polysulfide mono‐ and dianions have been investigated in the gas phase and in a polarizable continuum, and numerous reaction enthalpies as well as Gibbs energies are reported.
A Dual‐Functional Metallogel of Amphiphilic Copper(II) Quinolinol: Redox Responsiveness and Enantioselectivity
Authors: Miao Wangen , Zhang Li , Wang Xiufeng , Cao Hai , Jin Qingxian , Liu Minghua
Published: January 2013

A dual‐functional metallogel, which was based on the copper(II) complex of quinolinol‐substituted L‐glutamide, showed both redox‐responsive and enantioselective properties; moreover, the metallogels collapsed into a sol after reduction and could be revived upon subsequent oxidation. The supramolecular chirality and morphology also reversible changed with the gel–sol transition. Furthermore, the metallogels showed new enantioselective recognition towards chiral aromatic amino acids. A new emission band in the blue‐light region at around 393 nm appeared when the metallogels encountered L‐aromatic amino acids, whereas no new emission band was observed for the corresponding D‐aromatic amino acids. Such enantioselectivity only occurred in the gel state. No similar phenomenon could be observed in solution. This result suggested that, during the gel formation, the gelator molecules self‐assembled into ordered, chiral supramolecular structures and enhanced the enantiorecognition of the L‐aromatic amino acids.
Photophysical Properties and Conformational Effects on the Circular Dichroism of an Azobenzene–Cyclodextrin [1]Rotaxane and Its Molecular Components
Authors: Di Motta Simone , Avellini Tommaso , Silvi Serena , Venturi Margherita , Ma Xiang , Tian He , Credi Alberto , Negri Fabrizia
Published: January 2013

The photophysical properties of a multicomponent [1]rotaxane bearing a β‐cyclodextrin ring covalently connected to an axle comprising an azobenzene photoisomerisable moiety and a naphthalimide‐type fluorescent stopper are investigated by a combined experimental and computational study. The absorption and fluorescence spectra, and particularly the induced circular dichroism (ICD) signal, are determined. The latter shows a sign relation that cannot be rationalised in terms of the simple general rules commonly employed to analyse the ICD spectra of achiral guests encircled by chiral hosts. To assist the interpretation of experimental results, DFT and time‐dependent (TD) DFT calculations are performed to explore the availability of low‐energy conformations and to model their spectroscopic response. Molecular dynamics simulations performed in water show the interconversion of a number of conformers, the contribution of which to the ICD signal is in agreement with the observation.
Underpotential Deposition‐Induced Synthesis of Composition‐Tunable PtCu Nanocrystals and Their Catalytic Properties
Authors: Jiang Yaqi , Jia Yanyan , Zhang Jiawei , Zhang Lei , Huang Huang , Xie Zhaoxiong , Zheng Lansun
Published: January 2013

PtCu alloy octahedral nanocrystals (NCs) have been synthesized successfully by using N,N‐dimethylformamide as both the solvent and the reducing agent in the presence of cetyltrimethylammonium chloride. Cu underpotential deposition (UPD) is found to play a key role in the formation of the PtCu alloy NCs. The composition in the PtCu alloy can be tuned by adjusting the ratio of metal precursors in solution. However, the Cu content in the PtCu alloy NCs cannot exceed 50 %. Due to the fact that Cu precursor cannot be reduced to metallic copper and the Cu content cannot exceed 50 %, we achieved the formation of the PtCu alloy by using Cu UPD on the Pt surface. In addition, the catalytic activities of PtCu alloy NCs with different composition were investigated in electrocatalytic oxidation of formic acid. The results reveal that the catalytic performance is strongly dependent on PtCu alloy composition. The sample of Pt50Cu50 exhibits excellent activity in electrocatalytic oxidation of formic acid.
Synthesis and Biological Evaluation of the Forssman Antigen Pentasaccharide and Derivatives by a One‐Pot Glycosylation Procedure
Authors: Tanaka Hiroshi , Takeuchi Ryota , Jimbo Mitsuru , Kuniya Nami , Takahashi Takashi
Published: January 2013

The synthesis and biological evaluation of the Forssman antigen pentasaccharide and derivatives thereof by using a one‐pot glycosylation and polymer‐assisted deprotection is described. The Forssman antigen pentasaccharide, composed of GalNAcα(1,3)GalNAcβ(1,3)Galα(1,4)Galβ(1,4)Glc, was recently identified as a ligand of the lectin SLL‐2 isolated from an octocoral Sinularia lochmodes. The chemo‐ and α‐selective glycosylation of a thiogalactoside with a hemiacetal donor by using a mixture of Tf2O, TTBP and Ph2SO, followed by activation of the remaining thioglycoside, provided the trisaccharide at the reducing end in a one‐pot procedure. The pentasaccharide was prepared by the α‐selective glycosylation of the N‐Troc‐protected (Troc=2,2,2‐trichloroethoxycarbonyl) thioglycoside with a 2‐azide‐1‐hydroxyl glycosyl donor, followed by glycosidation of the resulting disaccharide at the C3 hydroxyl group of the trisaccharide acceptor in a one‐pot process. We next applied the one‐pot glycosylation method to the synthesis of pentasaccharides in which the galactosamine units were partially and fully replaced by galactose units. Among the three possible pentasaccharides, Galα(1,3)GalNAc and Galα(1,3)Gal derivatives were successfully prepared by the established method. An assay of the binding of the synthetic oligosaccharides to a fluorescent‐labeled SLL‐2 revealed that the NHAc substituents and the length of the oligosaccharide chain were both important for the binding of the oligosaccharide to SLL‐2. The inhibition effect of the oligosaccharide relative to the morphological changes of Symbiodinium by SLL‐2, was comparable to their binding affinity to SLL‐2. In addition, we fortuitously found that the synthetic Forssman antigen pentasaccharide directly promotes a morphological change in Symbiodinium. These results strongly indicate that the Forssman antigen also functions as a chemical mediator of Symbiodinium.
Five‐Year Soil Respiration Reflected Soil Quality Evolution in Different Forest and Grassland Vegetation Types in the Eastern Loess Plateau of China
Authors: Yan Junxia , Chen Liangfu , Li JunJian , Li Hongjian
Published: January 2013

Soil CO2 efflux in forest and grassland over 5 years from 2005 to 2009 in a semiarid mountain area of the Loess plateau, China, was measured. The aim was to compare the soil respiration and its annual and inter‐annual responses to the changes in soil temperature and soil water content between the two vegetation types for observing soil quality evolution. The differences among the five study years were the annual precipitation (320.1, 370.5, 508.8, 341.6, and 567.4 mm in 2005–2009, respectively) and annual distribution. The results showed that the seasonal change of soil respiration in both vegetation types was similar and controlled by soil temperature and soil water content. The mean soil respiration across 5 years in the forest (3.78 ± 2.68 µmol CO2 m−2 s−1) was less than that in the grassland (4.04 ± 3.06 µmol CO2 m−2 s−1), and the difference was significant. The drought soil in summer depressed soil respiration substantially. The Q10 value across 5‐year measurements was 2.89 and 2.94 for forest and grassland. When soil water content was between wilting point (WP) and field capacity (FC), the Q10 in both types increased with increasing soil water content, and when soil water content dropped to below WP, soil respiration and the Q10 decreased substantially. Although an exponential model was well fitted to predict the annual mean soil respiration for each single year data, it overestimated and underestimated soil respiration, respectively, in drought conditions and after rain for short periods of time during the year. The two‐variable models including temperature and water content variables could be well used to predict soil respiration for both types in all weather conditions. The models proposed are useful for understanding and predicting potential changes in the eastern part of Loess plateau in response to climate change.
Tissue flow cytometry immunophenotyping in the diagnosis and classification of non‐Hodgkin's lymphomas: A retrospective evaluation of 1,792 cases
Authors: Demurtas Anna , Stacchini Alessandra , Aliberti Sabrina , Chiusa Luigi , Chiarle Roberto , Novero Domenico
Published: January 2013

A retrospective analysis of 1,792 solid tissues suggestive of lymphoma, submitted over a 12‐year period, was carried out and flow cytometry (FC) results were compared with histologic findings. The final histologic diagnosis of cases documented in this report is as follows: 1,270 non‐Hodgkin's lymphomas (NHL); 17 composite lymphomas; four NHL plus carcinomas; five post‐transplant lymphoproliferative disorders; 105 Hodgkin's lymphomas (HL); eight acute leukemias; 42 tissue cancers; and 341 non‐neoplastic diseases. A strong correlation between morphology and FC data was observed among hematological malignancies (1,268/1,304, 97.2%) with the exception of HL. Among B‐NHL, FC detection of clonally restricted B‐cell allowed the identification of lymphomas that were not histologically clear and the differential diagnosis between follicular lymphoma and reactive hyperplasia. A high correlation level (r = 0.83; P < 0.0001) was obtained in comparing proliferation results obtained by FC and immunohistochemistry. Among T‐NHL, FC detection of an aberrant phenotype direct histologic diagnosis in cases having less than 20% of neoplastic cells. In nine cases, FC suggested the need to evaluate a neoplastic population, not morphologically evident. Results show that FC routinely performed on tissue samples suspected of lymphomas is a fundamental adjunct to morphology in the diagnosis of NHL and may enhance the performance of the histologic evaluation so as to achieve the final diagnosis. To the best of our knowledge, this is the first report in the literature of a wide series of tissues also studied by FC. © 2013 International Clinical Cytometry Society
Development of a C‐Terminal Site‐Specific PEGylated Analog of GLP‐1 with Improved Anti‐Diabetic Effects in Diabetic Mice
Authors: Gao Mingming , Tong Yue , Gao Xiangdong , Yao Wenbing
Published: January 2013

Preclinical Research

Glucagon‐like peptide‐1 (GLP‐1) is an attractive lead for antidiabetic drug development but its utility is limited due to poor in vivo stability. In this study, we developed a C‐terminal site‐specific PEGylated analog of GLP‐1 based on the structure‐activity relationship of GLP‐1. Using three steps of chromatography, we obtained the conjugate with a high purity. Polyethylene glycol (PEG) conjugation greatly enhanced GLP‐1 potency in vivo without changing its original conformation. In streptozotosin diabetic mice, this conjugate had an improved antidiabetic effect, as measured by fasting glucose/insulin/glycosylated serum protein, oral glucose tolerance test, and histochemical studies. Additionally, this PEG‐conjugated peptide delayed gastric emptying without significant effects on body weight gain. Our data indicate that this conjugate may be a promising lead for the development of antidiabetic drugs.
Antiarrhythmic Efficacy of CPUY11018 Under Pathological Conditions
Authors: Xu Jing , Yu Peng , Yang Qian , Meng Jia‐ning , Shan Jiao‐jiao , You Qi‐dong , Tang Yi‐qun
Published: January 2013

Preclinical Research

In the present study, we investigated the antiarrhythmic potential of the multichannel blocker CPUY11018 (CY18) in rat cardiac hypertrophy, induced using 7‐day treatment with isoproterenol (ISO) (2.5 mg/kg day, s.c.). Arrhythmias were produced using a coronary ligation‐reperfusion procedure. CY18 (3 and 10 mg/kg per day, i.p.) and valsartan (10 mg/kg per day, p.o.) were administrated on days 4–7 of ISO treatment. Heart weight index, hemodynamic parameters, electrocardiogram (ECG II) parameters, and arrhythmic scores were monitored and recorded. We examined the ability of CY18 to block the IKr channel under conditions of acidosis and excess reactive oxygen species production in CHO cells expressing the hERG. CY18 had strong antiarrhythmic effects, potentially due to multichannel inhibition. The protective role of CY18 against ISO‐induced myocardial hypertrophy was further confirmed using ECG. Incidences of ventricular tachycardia and ventricular fibrillation, heart weight/body weight ratios, and arrhythmic scores were higher in the model group and were suppressed with CY18 treatment. Under simulated pathological conditions, the inhibitory effect of CY18 was impaired in cells treated with 30 μM H2O2, which was more effective than acidosis in attenuating CY18‐induced inhibition of hERG channel activity.
CD28 costimulation: Walking the immunological tightrope
Authors: Sansom David M. , Walker Lucy S. K.
Published: January 2013

CD28 function has typically been associated with the generation of effector T‐cell responses to Ag. However, it is also clear that CD28 plays an important role in Treg‐cell biology. Understanding which functions predominate is important when designing therapeutic interventions based on CD28 targeting. An article by Hünig and colleagues [Eur. J. Immunol. 2013. 43: 188–193] in this issue of the European Journal of Immunology uses an inducible gene deletion approach to reveal that, in the steady state, Treg cells intrinsically require CD28 signals for their maintenance in the periphery, whereas homeostasis of conventional T cells is relatively unaffected. Here we highlight the delicate balance created by the ability of CD28 to modulate both regulatory and effector T‐cell responses.
Deciphering the syntax of cytotoxic lymphocyte degranulation
Authors: Lopez Jamie A. , Voskoboinik Ilia
Published: January 2013

In the killer lymphocyte, the targeted delivery of perforin‐ and granzyme‐containing cytotoxic granules to the immunological synapse is crucial for the eradication of pathogen‐infected or transformed targets. This process is achieved through a tightly controlled and highly efficient granule exocytosis pathway. Mutations in the granule trafficking proteins Munc13–4, syntaxin 11, Munc18–2 or Rab27 leads to a fatal lapse of immune surveillance and can be manifested as haemophagocytic lymphohistiocytosis in humans. Elucidation of the role of these proteins in exocytic trafficking is pivotal for our understanding of their role in health and disease. In this issue of the European Journal of Immunology, D'Orlando et al. [Eur. J. Immunol. 2013. 43: 194‐208] make an important step in this direction, as they generate and characterise syntaxin 11 deficient mice. Herein, we discuss the role of syntaxin‐11 in soluble NSF (N‐ethylmaleimide sensitive fusion) attachment protein receptors complex formation leading to cytotoxic lymphocyte degranulation and its importance in maintaining immune homeostasis.
Palladium‐Catalyzed ortho‐Aroylation of 2‐Arylbenzothiazoles and 2‐Arylbenzoxazoles with Aldehydes
Authors: Banerjee Arghya , Santra Sourav Kumar , Guin Srimanta , Rout Saroj Kumar , Patel Bhisma K.
Published: January 2013

An efficient protocol for the ortho‐aroylation of 2‐arylbenzothiazoles and 2‐arylbenzoxazoles has been developed using aldehydes as the aroyl source. This Pd‐catalyzed substrate‐directed sp2‐hybridized C–H bond functionalization occurs in the presence of the oxidant tert‐butyl hydroperoxide. A variety of functional groups on the 2‐arylbenzothiazoles, 2‐arylbenzoxazoles, and aldehydes are tolerated under the reaction conditions. Regioselective aroylation at the less hindered ortho position was observed for meta‐substituted 2‐arylbenzothiazoles.
Comparative Study of Lead(II) Selective Poly(vinyl chloride) Membrane Electrodes Based on Podand Derivatives as Ionophores
Authors: Singh Sanjay , Rani Geeta , Singh Gyanendra , Agarwal Himanshu
Published: January 2013

The two podand chelates based on diethylsulfide, 1,5‐bis(2′‐hydroxy‐4′‐nitrophenoxy)‐3‐thiapentane (L1) and 1,5‐bis(8′‐oxybenzopyridine)‐3‐thia pentane (L2), have been synthesized and explored as neutral ionophores for preparing poly(vinyl chloride) based membrane electrodes selective to Pb2+. The addition of anionic additives and various plasticizers has been found to substantially improve the performance of the electrode. The best performance was obtained with the electrode No. 1 having a membrane of ionophore (L1) with the composition PVC:o‐NPOE:ionophore (L1):NaTFPB (%w/w) of 33 : 62 : 3 : 2. The electrode exhibits Nernstian response with a slope of 31.57±0.3 mV decade−1 of activity in the concentration range from 2.0×10−9 to 1.0×10−1 M Pb2+, performs satisfactorily over a wide pH range (1.6–7.0), with a fast response time (5 s).
Time‐variant sustainability assessment of seismically vulnerable bridges subjected to multiple hazards
Authors: Dong You , Frangopol Dan M. , Saydam Duygu
Published: January 2013

In the design and assessment of structures, the aspects regarding the future performance are gaining increased attention. A wide range of performance measures is covered by ‘sustainability’ to reflect these aspects. There is the need for well established methods for quantifying the metrics of sustainability. In this paper, a framework for assessing the time‐variant sustainability of bridges associated with multiple hazards considering the effects of structural deterioration is presented. The approach accounts for the effects of flood‐induced scour on seismic fragility. Sustainability is quantified in terms of its social, environmental, and economic metrics. These include the expected downtime and number of fatalities, expected energy waste and carbon dioxide emissions, and the expected loss. The proposed approach is illustrated on a reinforced concrete bridge. The effects of corrosion on reinforcement bars and concrete cover spalling are accounted. The seismic fragility curves at different points in time are obtained through nonlinear finite element analyses. The variation of the metrics of sustainability in time is presented. The effects of flood‐induced scour on both seismic fragility and metrics are also investigated. Copyright © 2013 John Wiley & Sons, Ltd.
Diclofenac: New data on chronic toxicity and bioconcentration in fish
Authors: Memmert Ulrich , Peither Armin , Burri Roland , Weber Klaus , Schmidt Thomas , Sumpter John P. , Hartmann Andreas
Published: January 2013

Diclofenac (DCF) is a widely used nonsteroidal anti-inflammatory drug that is regularly detected in surface waters. To support a robust aquatic risk assessment, two early life stage (ELS) tests, compliant with the Organisation for Economic Co-operation and Development (OECD) test guideline 210, were conducted in rainbow trout and in zebrafish. Population relevant endpoints, such as hatching, growth, and survival, and in the trout study, histopathological effects in potential target organs, were examined. The bioconcentration of DCF in rainbow trout was measured in a separate study according to OECD test guideline 305. The bioconcentration factor (BCF) in rainbow trout remained below 10, demonstrating no relevant bioconcentration of DCF in fish. In the rainbow trout ELS test, the no observed effect concentration (NOEC) including histopathology was 320 µg/L. The effect of DCF on zebrafish growth was less clear, and the NOEC can be interpreted as 10 µg/L. However, for a number of reasons, the authors consider the moderately reduced growth of zebrafish exposed to concentrations of up to 320 µg/L not a repeatable, treatment-related effect of DCF. This leads us to a conclusion that DCF has, with high probability, no adverse effect on both fish species up to 320 µg/L. This NOEC indicates a sufficient safety margin for fish populations, because concentrations of DCF in European rivers are in the range of ng/L to low µg/L. Environ. Toxicol. Chem. 2013;32:442–452. © 2013 SETAC
Ruxolitinib: JAK2 inhibitor for treatment of myelofibrosis
Authors: Mead Adam
Published: January 2013

Ruxolitinib is an orally administered JAK2 inhibitor for the treatment of disease‐related splenomegaly or symptoms in primary myelofibrosis or myelofibrosis due to polycythaemia vera or essential thrombocythaemia. In our Drug profile Dr Adam Mead presents the clinical data relating to its efficacy and adverse events and comments on its place in therapy. Copyright © 2013 John Wiley & Sons, Ltd.
Dexmedetomidine: a unique clinical profile in ICU sedation
Authors: Chaplin Steve
Published: January 2013

Dexmedetomidine is a sedating agent with a pharmacological and therapeutic profile that is unlike those of the most commonly used sedative agents (midazolam and propofol). In this article, we provide an over view of dexmedetomidine in terms of its pharmacokinetics and pharmacodynamics, and describe its place in the management of patients in intensive care. Copyright © 2013 John Wiley & Sons, Ltd.
The astrocyte in multiple sclerosis revisited
Authors: Brosnan Celia F. , Raine Cedric S.
Published: January 2013

Among the constituent cell types of the multiple sclerosis (MS) plaque, the astrocyte has been the least considered as a player in the pathogenesis of the lesion. Traditionally, it has been assigned a secondary scarring role with little or no role in lesion formation or repair. However, the recent upsurge of interest in the demyelinating condition neuromyelitis optica (NMO) has resulted in NMO being identified as the first disease of myelin in which primary damage to astrocytes, resulting from a humoral immune response that forms against the water channel aquaporin‐4, has been documented. This finding in NMO prompted us to re‐examine data and material from cases of MS displaying active lesions. Our reappraisal revealed unambiguous early damage to perivascular astrocyte end‐feet and to hypertrophic astrocytes in the adjacent parenchyma, but whether this was a primary event was difficult to evaluate due to concomitant edema and inflammation in these acute lesions. The astrocyte damage was long‐lasting since resolving lesions displaying remyelination also showed defects in the integrity of the astrocytic covering around blood vessels. Analysis of our findings and of the astrocytic literature supports multiple roles for the astrocyte in the evolution of changes encountered in MS depending upon lesion stage and lesion topography. At variance with the somewhat inhibitory role of the astrocyte is the abundant and growing evidence for this cell to actively participate in both lesion development and repair. We propose that the unequivocal selective early involvement of the astrocyte in MS lesions may have therapeutic relevance. © 2013 Wiley Periodicals, Inc.
Sulfatide decrease in myelin influences formation of the paranodal axo‐glial junction and conduction velocity in the sciatic nerve
Authors: Hayashi Akiko , Kaneko Naoki , Tomihira Chiaki , Baba Hiroko
Published: January 2013

Cerebroside sulfotransferase (CST) catalyzes the production of sulfatide, which is one of the major glycolipids in myelin. Homozygous CST knockout mice were shown to be completely deficient in sulfatide. They were born healthy but began to display progressive neurological deficits from 6 weeks of age. Severe abnormalities of paranodal regions and changes in axonal ion channel distribution were prominent in both the central and peripheral nervous systems. But whether partial decreases in myelin sulfatide levels influence paranodal formation, as well as nerve conduction velocity (NCV), is largely unknown. To determine the functional significance of sulfatide content in myelin, we performed electrophysiological, morphological, and biochemical analyses using heterozygote, homozygote, and wild‐type mouse peripheral nerves and compared the results with individual sulfatide content. NCVs were significantly reduced in homozygote animals compared with wild‐type mice. In contrast, these values were markedly varied in individual heterozygote mice. On the basis of NCV values, we divided heterozygous mice into two groups: mice with mild but significant reduction of NCV and those with normal NCV. Teased nerve fibers obtained from individual mouse sciatic nerves were immunostained, and Na+ channel and Caspr cluster lengths were measured to determine abnormal levels of junctional formation at the paranode. Furthermore, sulfatide content in each sciatic nerve was examined by thin layer chromatography. The results demonstrated significant correlations among sulfatide level, severity of paranodal abnormality, and reduction of NCV. Thus, the fine regulation of myelin sulfatide content by CST is important for normal function of myelinated axons. © 2013 Wiley Periodicals, Inc.
A comparative study of glial and non‐neural cell properties for transplant‐mediated repair of the injured spinal cord
Authors: Toft Andrew , Tome Mercedes , Barnett Susan C. , Riddell John S.
Published: January 2013

Cell transplantation is one strategy for encouraging regeneration after spinal cord injury and a range of cell types have been investigated for their repair potential. However, variations in study design complicate determination of which cells are most effective. In this study we have carried out a direct comparison of the regenerative and integrative properties of several cell preparations following transplantation into the lesioned rat spinal cord. Transplants included: (i) purified olfactory ensheathing cells (OECs) and (ii) fibroblast‐like cells, from olfactory bulb (OBFB‐L), (iii) a 50:50 mixture of (i) and (ii) (OEC/OBFB‐L), (iv) dissociated nasal mucosa (OM), (v) purified peripheral nerve Schwann cells (SCs), (vi) peripheral nerve fibroblasts, and (vii) skin fibroblasts (SF). All transplants supported axonal regeneration: OECs and SCs promoted the greatest regeneration while OBFB‐like cells were least efficient and mixed cell populations were less effective than purified populations. Tract‐tracing experiments demonstrated that none of the cell types promoted regeneration beyond the lesion. Although all cell types prevented cavity formation, the extent of astrocytic hypertrophy [GFAP immunoreactivity (IR) at the transplant/lesion site] differed markedly. OECs and SCs were associated with the least GFAP‐IR, fibroblasts and fibroblast‐like cells resulted in greater GFAP‐IR while hypertrophy surrounding transplants of OM was most extensive. These differences in host‐transplant reactivity were confirmed by transplanting cells into normal spinal cord where the cellular interaction is not complicated by injury. Thus, purified glial cells have advantages for transplant‐mediated repair, combining maximal support for axonal regeneration with a minimal astrocytic reaction around the transplant site. © 2013 Wiley Periodicals, Inc.
MAT2B-GIT1 interplay activates MEK1/ERK 1 and 2 to induce growth in human liver and colon cancer
Authors: Peng Hui , Dara Lily , Li Tony W.H. , Zheng Yuhua , Yang Heping , Tomasi Maria Lauda , Tomasi Ivan , Giordano Pasquale , Mato Jose M. , Lu Shelly C.
Published: January 2013

Methionine adenosyltransferase 2B (MAT2B) encodes for two variant proteins (V1 and V2) that promote cell growth. Using in-solution proteomics, GIT1 (G Protein Coupled Receptor Kinase Interacting ArfGAP 1) was identified as a potential interacting partner of MAT2B. Here, we examined the functional significance of this interplay. Coimmunoprecipitation experiments examined protein interactions. Tissue expression levels of proteins were examined using immunohistochemistry and western blotting. Expression levels of proteins were varied using transient knockdown or overexpression to observe the effect of alterations in each protein on the entire complex. Direct interaction among individual proteins was further verified using

in vitro

translated and recombinant proteins. We found both MAT2B variants interact with GIT1. Overexpression of V1, V2, or GIT1 activated mitogen-activated protein kinase kinase 1 (MEK1) and extracellular signal-regulated kinase (ERK), raised cyclin D1 protein level, and increased growth, whereas the opposite occurred when V1, V2, or GIT1 was knocked down. MAT2B and GIT1 require each other to activate MEK1/ERK and increase growth. MAT2B directly interacts with MEK1, GIT1, and ERK2. Expression level of V1, V2, or GIT1 directly influenced recruitment of GIT1 or MAT2B and ERK2 to MEK1, respectively. In pull-down assays, MAT2B directly promoted binding of GIT1 and ERK2 to MEK1. MAT2B and GIT1 interact and are overexpressed in most human liver and colon cancer specimens. Increased expression of V1, V2, or GIT1 promoted growth in an orthotopic liver cancer model, whereas increased expression of either V1 or V2 with GIT1 further enhanced growth and lung metastasis.

Conclusion:

MAT2B and GIT1 form a scaffold, which recruits and activates MEK and ERK to promote growth and tumorigenesis. This novel MAT2B/GIT1 complex may provide a potential therapeutic gateway in human liver and colon cancer.