bluuebunny/crossref_metadata_2025 huggingface dataset:
CT versus FDG‐PET/CT response evaluation in patients with metastatic colorectal cancer treated with irinotecan and cetuximab
Authors: Skougaard Kristin , Johannesen Helle Hjorth , Nielsen Dorte , Schou Jakob Vasehus , Jensen Benny Vittrup , Høgdall Estrid V. S. , Hendel Helle Westergren
Published: June 2014

We compared morphologic computed tomography (CT)‐based to metabolic fluoro‐deoxy‐glucose (FDG) positron emission tomography (PET)/CT‐based response evaluation in patients with metastatic colorectal cancer and correlated the findings with survival and KRAS status. From 2006 to 2009, patients were included in a phase II trial and treated with cetuximab and irinotecan every second week. They underwent FDG‐PET/CT examination at baseline and after every fourth treatment cycle. Response evaluation was performed prospectively according to Response Evaluation Criteria in Solid Tumors (RECIST 1.0) and retrospectively according to Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST). Best overall responses were registered. Sixty‐one patients were eligible for response evaluation. Partial response (PR) rate was 18%, stable disease (SD) rate 64%, and progressive disease (PD) rate 18%. Partial metabolic response (PMR) rate was 56%, stable metabolic disease rate 33%, and progressive metabolic disease (PMD) rate 11%. Response agreement was poor, κ‐coefficient 0.19. Hazard ratio for overall survival for responders (PR/PMR) versus nonresponders (PD/PMD) was higher for CT‐ than for FDG‐PET/CT evaluation. Within patients with KRAS mutations, none had PR but 44% had PMR. In conclusion, morphologic and metabolic response agreement was poor primarily because a large part of the patients shifted from SD with CT evaluation to PMR when evaluated with FDG‐PET/CT. Furthermore, a larger fraction of the patients with KRAS mutations had a metabolic treatment response.
Tagging Live Cells that Express Specific Peptidase Activity with Solid‐State Fluorescence
Authors: Prost Maxime , Canaple Laurence , Samarut Jacques , Hasserodt Jens
Published: June 2014

A three‐component probe harnesses the extraordinary properties of a solid‐state fluorophore for the detection of living cells exhibiting a particular peptidase activity. The off–on mode by which the probe operates, the bright fluorescence of the resulting precipitate, and the rapid response allow an exceptional signal‐to‐background ratio during microscopic imaging. A tertiary carbamate link between the spacer and phenolic fluorophore is at the heart of the probe's long‐term stability. The degree of chlorination of the probe determines its response time and thus its suitability for live‐cell analysis. Our probe also allows highly resolved localization of peptidase activity during gel analysis or on agar. In comparison, probes releasing soluble fluorophores demonstrate complete diffusion of the fluorescent signal. These results demonstrate the probe's potential for diverse biomedical applications, including high‐fidelity flow cytometry and sensitive colony assays.
Effects of carbon‐ion beam irradiation on the angiogenic response in lung adenocarcinoma A549 cells
Authors: Liu Yuanyuan , Liu Yang , Zhang Hong , Sun Chao , Zhao Qiuyue , Di Cixia , Li Hongyan , Gan Lu , Wang Yali
Published: June 2014

Radiotherapy has been focused mainly on killing cancer cells, and little attention has been paid to the process supporting tumor growth and metastasis, including the process of angiogenesis. To investigate the effects of carbon‐ion irradiation on angiogenesis in lung cancer cells, we examined the expression of vascular endothelial growth factor and basic fibroblast growth factor in the tumor conditioned medium (TCM) of A549 cells exposed to carbon‐ion or X‐ray irradiation, as well as endothelial cell growth, invasion, and tube formation induced by TCM. No changes in vascular endothelial growth factor secretion were detected in the TCM of A549 cells exposed to carbon‐ion irradiation at 2 or 4 Gy, whereas 1 Gy of irradiation significantly decreased vascular endothelial growth factor and basic fibroblast growth factor levels. Carbon‐ion irradiation at 1 Gy inhibited endothelial cell invasion and tube formation. The TCM from A549 cells irradiated with X‐ray promoted angiogenesis, whereas the TCM of A549 cells exposed to carbon‐ion irradiation at 2 or 4 Gy had no effect. These findings suggest that carbon‐ion irradiation at 1 Gy significantly suppressed the process of angiogenesis in vitro by inhibiting endothelial cell invasion and tube formation, which are related to vascular endothelial growth factor and basic fibroblast growth factor production.
Evolutionarily conserved organization of the dopaminergic system in lamprey: SNc/VTA afferent and efferent connectivity and D2 receptor expression
Authors: Pérez‐Fernández Juan , Stephenson‐Jones Marcus , Suryanarayana Shreyas M. , Robertson Brita , Grillner Sten
Published: June 2014

The dopaminergic system influences motor behavior, signals reward and novelty, and is an essential component of the basal ganglia in all vertebrates including the lamprey, one of the phylogenetically oldest vertebrates. The intrinsic organization and function of the lamprey basal ganglia is highly conserved. For instance, the direct and indirect pathways are modulated through dopamine D1 and D2 receptors in lamprey and in mammals. The nucleus of the tuberculum posterior, a homologue of the substantia nigra pars compacta (SNc)/ventral tegmental area (VTA) is present in lamprey, but only scarce data exist about its connectivity. Likewise, the D2 receptor is expressed in the striatum, but little is known about its localization in other brain areas. We used in situ hybridization and tracer injections, both in combination with tyrosine hydroxylase immunohistochemistry, to characterize the SNc/VTA efferent and afferent connectivity, and to relate its projection pattern with D2 receptor expression in particular. We show that most features of the dopaminergic system are highly conserved. As in mammals, the direct pallial (cortex in mammals) input and the basal ganglia connectivity with the SNc/VTA are present as part of the evaluation system, as well as input from the tectum as the evolutionary basis for salience/novelty detection. Moreover, the SNc/VTA receives sensory information from the olfactory bulbs, optic tectum, octavolateral area, and dorsal column nucleus, and it innervates, apart from the nigrostriatal pathway, several motor‐related areas. This suggests that the dopaminergic system also contributes to the control of different motor centers at the brainstem level. J. Comp. Neurol. 522:3775–3794, 2014. © 2014 Wiley Periodicals, Inc.
Masonry – a sustainable building material / Mauerwerk – ein nachhaltiges Baumaterial
Authors: Graubner Carl‐Alexander , Pohl Sebastian
Published: June 2014

The construction and real estate industry in general and residential buildings in particular are essential pillars of the national sustainability strategy in Germany and extremely important for resilient socio‐economic development. By performing life‐cycle examinations of different building types, the Institute for Concrete and Masonry Structures at Darmstadt University of Technology has analysed the sustainability characteristics of residential masonry buildings with regard to common German sustainability certification systems. This paper gives an overview of the key findings of the examinations. It is a condensed version of the authors’ article for the 9th International Masonry Conference 2014 in Portugal [1] and at the same time a preview of a forthcoming paper in this journal (Vol. 18, No. 5).
Layer‐by‐Layer Deposition of Highly Transparent Multifunctional Gd2O3:RE/SiO2 (RE = Eu and Tb) Films
Authors: Lee Byung‐Il , Jeong Heejin , Byeon Song‐Ho
Published: June 2014

Transparent, luminescent (Gd2O3:RE/SiO2) thin films (RE = Eu and Tb) have been fabricated by annealing [RE‐doped layered gadolinium hydroxide (LGdH:RE) nanosheet/SiO2 nanoparticle]n films (n = the number of deposition cycles) deposited on a single quartz glass substrate by the layer‐by‐layer (LbL) assembly technique. To avoid energy transfer between different activator ions, which frequently occurs when multiple activator‐doped LGdHs are used as precursor nanosheets, the emission colors of our oxide films were tuned by changing the mixing ratios of the individual LGdH:Eu and LGdH:Tb colloidal solutions used in the LbL deposition. Deposited films of sufficient thickness (n = 30) displayed bright emission colors ranging from green to red under 254 nm UV irradiation, depending on the mixing ratio. Although the large number of deposition cycles resulted in a lack of antireflection properties in the films, the porous surfaces induced by SiO2 nanoparticles led to superhydrophilic and antifogging properties without significant loss of transparency in the visible range compared with the bare quartz substrate.
Impact of the Presence of Octadecylamine on the Properties of Hydrothermally Prepared CoFe2O4 Nanoparticles
Authors: Georgiadou Violetta , Dendrinou‐Samara Catherine
Published: June 2014

CoFe2O4 magnetic nanoparticles (MNPs) were synthesized in a new synthetic system from metal acetylacetonates in the presence of octadecylamine (ODA) in autoclaves with subcritical water. By altering the water extent and ratio of the precursors, four samples were isolated. High crystallinity MNPs of various sizes (26, 15, 18, 9 nm) and saturation magnetization (71, 87, 93, 64 emu g–1) were formed. The organic coating was characterized by FTIR spectroscopy, 1H NMR and 13C NMR spectroscopy, and thermogravimetric analysis (TGA), and the free amine groups were detected by a ninhydrin assay. Under the present conditions, the CoFe2O4 MNPs were covered by a bilayer consisting of N‐octadecylamide and ODA. The MNPs were converted into fluorescence probes through the formation of a sulfonamide bond between ODA and sulforhodamine B (SRB). NMR relaxometric measurements were performed for MNPs modified with SRB, cetyltrimethylammonium bromide, and by 2,3‐dimercaptosuccinic acid. The bimodal magnetic fluorescent MNPs showed relaxivity values of up to r2 = 219.5 mM–1 s–1, which renders them promising as dual agents.
Functionalization of Imidazo[1,2‐a]pyridines by Means of Metal‐Catalyzed Cross‐Coupling Reactions
Authors: Koubachi Jamal , El Kazzouli Saïd , Bousmina Mosto , Guillaumet Gérald
Published: June 2014

This review surveys recent developments (reported in the last fifteen years) in organometallic‐chemistry‐based methods for the functionalization of imidazo[1,2‐a]pyridines, in particular the decoration of the pyridine and imidazole rings by means of reactions such as Sonogashira, Heck, Negishi, Suzuki–Miyaura, and Stille cross‐coupling, as well as by C–H activation, C‐arylation, C‐alkenylation, and carbonylation. Results relating to one‐pot double functionalization of two different positions on the imidazo[1,2‐a]pyridine system are also reviewed. Procedures in which metal‐based catalysis is not involved in the functionalization of imidazo[1,2‐a]pyridines are not included.
Spinal release of tumour necrosis factor activates c‐Jun N‐terminal kinase and mediates inflammation‐induced hypersensitivity
Authors: Bas D.B. , Abdelmoaty S. , Sandor K. , Codeluppi S. , Fitzsimmons B. , Steinauer J. , Hua X.Y. , Yaksh T.L. , Svensson C.I.
Published: June 2014

Background

Mounting evidence points to individual contributions of tumour necrosis factor‐alpha (TNF) and the c‐Jun N‐terminal kinase (JNK) pathway to the induction and maintenance of various pain states. Here we explore the role of spinal TNF and JNK in carrageenan‐induced hypersensitivity. As links between TNF and JNK have been demonstrated in vitro, we investigated if TNF regulates spinal JNK activity in vivo.

Methods

TNF levels in lumbar cerebrospinal fluid (CSF) were measured by enzyme‐linked immunosorbent assay, spinal TNF gene expression by real‐time polymerase chain reaction and TNF protein expression, JNK and c‐Jun phosphorylation by western blotting. The role of spinal TNF and JNK in inflammation‐induced mechanical and thermal hypersensitivity was assessed by injecting the TNF inhibitor etanercept and the JNK inhibitors SP600125 and JIP‐1 intrathecally (i.t.). TNF‐mediated regulation of JNK activity was examined by assessing the effect of i.t. etanercept on inflammation‐induced spinal JNK activity.

Results

TNF levels were increased in CSF and spinal cord following carrageenan‐induced inflammation. While JNK phosphorylation followed the same temporal pattern as TNF, c‐jun was only activated at later time points. Intrathecal injection of TNF and JNK inhibitors attenuated carrageenan‐induced mechanical and thermal hypersensitivity. TNF stimulation induced JNK phosphorylation in cultured spinal astrocytes and blocking the spinal actions of TNF in vivo by i.t. injection of etanercept reduced inflammation‐induced spinal JNK activity.

Conclusions

Here we show that spinal JNK activity is dependent on TNF and that both TNF and the JNK signalling pathways modulate pain‐like behaviour induced by peripheral inflammation.
Nonlinear finite element analysis of three‐dimensional free and harmonically forced vibrations of stranded conductor cables
Authors: Oliveto Nicholas D. , Sivaselvan Mettupalayam V.
Published: June 2014

The 3D finite deformation beam model originally developed by Simo is appropriately modified to derive a finite element formulation for the static and dynamic analysis of flexible electrical conductors. In contrast to what is currently carried out in the literature, a linear viscoelastic constitutive equation and an additional mass proportional damping mechanism are introduced to account for energy dissipation in a physically consistent way. The model is used for simulation of free and forced vibration tests performed on an actual electrical conductor. Energy balance calculations illustrate the reliability of the computations. The experiments reveal amplitude dependence of both stiffness and damping, pointing out the presence of material nonlinearity in the cable. The development of numerical models that can account for the amplitude dependence of bending stiffness and energy dissipation capacity is subject of current computational and experimental work. Copyright © 2014 John Wiley & Sons, Ltd.
Novel PRKD gene rearrangements and variant fusions in cribriform adenocarcinoma of salivary gland origin
Authors: Weinreb Ilan , Zhang Lei , Tirunagari Laxmi MS , Sung Yun‐Shao , Chen Chun‐Liang , Perez‐Ordonez Bayardo , Clarke Blaise A , Skalova Alena , Chiosea Simion I , Seethala Raja R , Waggott Daryl , Boutros Paul C , How Christine , Liu Fei‐Fei , Irish Jonathan C , Goldstein David P , Gilbert Ralph , ud Din Nasir , Assaad Adel , Hornick Jason L , Thompson Lester DR , Antonescu Cristina R
Published: June 2014

Polymorphous low‐grade adenocarcinoma (PLGA) and cribriform adenocarcinoma of minor salivary gland (CAMSG) are low‐grade carcinomas arising most often in oral cavity and oropharynx, respectively. Controversy exists as to whether these tumors represent separate entities or variants of one spectrum, as they appear to have significant overlap, but also clinicopathologic differences. As many salivary carcinomas harbor recurrent translocations, paired‐end RNA sequencing and FusionSeq data analysis was applied for novel fusion discovery on two CAMSGs and two PLGAs. Validated rearrangements were then screened by fluorescence in situ hybridization (FISH) in 60 cases. Histologic classification was performed without knowledge of fusion status and included: 21 CAMSG, 18 classic PLGA, and 21 with “mixed/indeterminate” features. The RNAseq of 2 CAMSGs showed ARID1A‐PRKD1 and DDX3X‐PRKD1 fusions, respectively, while no fusion candidates were identified in two PLGAs. FISH for PRKD1 rearrangements identified 11 additional cases (22%), two more showing ARID1A‐PRKD1 fusions. As PRKD2 and PRKD3 share similar functions with PRKD1 in the diacylglycerol and protein kinase C signal transduction pathway, we expanded the investigation for these genes by FISH. Six additional cases each showed PRKD2 and PRKD3 rearrangements. Of the 26 (43%) fusion‐positive tumors, there were 16 (80%) CAMSGs and 9 (45%) indeterminate cases. A PRKD2 rearrangement was detected in one PLGA (6%). We describe novel and recurrent gene rearrangements in PRKD1–3 primarily in CAMSG, suggesting a possible pathogenetic dichotomy from “classic” PLGA. However, the presence of similar genetic findings in half of the indeterminate cases and a single PLGA suggests a possible shared pathogenesis for these tumor types. © 2014 Wiley Periodicals, Inc.
Human Resource Development ≠ Human Resource Management: So What Is It?
Authors: Werner Jon M.
Published: June 2014

This editorial describes the fields of human resource management (HRM) and human resource development (HRD), including brief histories of both areas. Distinctions between the fields are made, as well as overlap between them. Ideas are presented concerning ways that manuscripts submitted to this journal can be best positioned for successful outcomes. A framework from Mankin () is used to depict overlap between organizational strategy and structure, organizational culture, HRM, and HRD. As these topics converge in greater alignment, the need for and centrality of strong HRD principles and practices should increase.
Development of realistic environmental release factors based on measured data: Approach and lessons from the EU metal industry
Authors: Verdonck Frederik AM , Van Assche Frank , Hicks Keegan , Mertens Jelle , Voigt Astrid , Verougstraete Violaine
Published: June 2014

The assessment of environmental exposure and risks associated with the production or use of a substance on an industrial site includes the estimation of the releases to the environment. In the absence of measured release data on the specific substance, a risk assessor would rely on default release factors to the environmental compartments as developed in international, national, or regional context. Because a wide variety of substances, processes, and uses has to be covered, default release factors are as a rule conservative, usually leading to significant overprediction of releases and hence to overpredicted environmental exposure concentrations and risks. In practice, unrealistic and worst-case predictions do not support a more efficient management of releases and risk. The objective of this article is to propose a more realistic approach to characterize the environmental releases from manufacture, processing, and downstream uses of the metals and their compounds. Although developed in the European Union (EU), this approach can also be used in other regions and in other chemical management systems addressing metals. A database consisting of more than 1300 recent (1993–2010), site-specific measured release factors to air and water of 18 different metals from various EU Member States was compiled and used to calculate average and reasonable worst-case release factors for multiple metal manufacture and industrial use processes. The parameters influencing releases to water were found to depend predominantly on life cycle step (manufacture and/or use), the sector and/or the solid–water partition coefficient (Kd). The release factors can be used as advanced tier instrument in environmental safety assessments, increasing the realism of the estimates while still keeping a sufficient level of conservatism. Integr Environ Assess Manag 2014;10:529–538. © 2014 SETAC

Key Point

Development of realistic environmental release factors based on measured data from the EU metal industry.
New Alkoxy‐Functionalized Naphthodithiophene‐Based Semiconducting Oligomers and Polymers
Authors: Huang Chun , Hu Yan , Zheng Yan , Drees Martin , Pan Hualong , Facchetti Antonio
Published: June 2014

We report the syntheses and characterization of two bent dialkoxy‐substituted naphthodithiophene (bNDT) isomers as well as of the corresponding bNDT‐based small molecule and polymer semiconductors for organic field‐effect transistors and organic photovoltaics. The bNDT‐based building blocks exhibit improved oxidation potential and photo‐ and air stability versus the benzodithiophene and linear naphthodithiophene counterparts. Incorporation of the dialkoxy substituents enables film fabrication from solution and control of the molecular solid‐state packing. Among these semiconductors, the polymer P1 exhibits good hole field‐effect mobility of about 0.4 cm2 Vs−1withIon/Ioff>104for low‐temperature annealing. These results indicate that bNDT is a promising building block for optoelectronic semiconducting materials.
Selenium in Diketopyrrolopyrrole‐based Polymers: Influence on Electronic Properties and Charge Carrier Mobilities
Authors: Dhar Joydeep , Kanimozhi Catherine , Yaccobi‐Gross Nir , Anthopoulos Thomas D. , Salzner Ulrike , Patil Satish
Published: June 2014

Diketopyrrolopyrrole (DPP)‐based π‐conjugated copolymers with thiophene have exceptionally high electron mobilities. This paper investigates electronic properties and charge carrier mobilities of selenophene containing analogues. Two new copolymers, with alternating thiophene DPP (TDPP) and selenophene DPP (SeDPP) units, were synthesized. Two side‐chains, hexyl (Hex) and triethylene glycol (TEG) were employed, yielding polymers designated as PTDPPSeDPP‐Hex and PTDPPSeDPP‐TEG. Selenophene systems have smaller band gaps, with concomitant enhancement of the stability of the reduced state. For both polymers, ambipolar mobilities were observed in organic field‐effect transistors (OFET). Grazing incidence X‐ray diffraction (GIXD) data indicates preferential edge‐on orientation of PTDPPSeDPP‐TEG, which leads to superior charge transport properties of the TEG substituted polymer, as compared to its Hex analogue. Time‐dependent‐density functional theory (TDDFT) calculations corroborate the decrease in the optical band gap with the inclusion of selenophene. Ambipolar charge transport is rationalized by exceptionally wide conduction bands. ΔSCF calculations confirm the larger electron affinity, and therefore the greater stability, of the reduced form of the selenophene‐containing DPP polymer in presence of chloroform.
Zirconium Phosphate Nanoparticles for Solvent Free Acetylation of Phenols and Salicylic Acid: An Efficient and Eco‐friendly Solid Acid Catalyst for Synthesis of Acetyl Salicylic Acid (Aspirin)
Authors: Hajipour Abdol Reza , Karimi Hirbod
Published: June 2014

A facile synthesis of zirconium phosphate (ZP) nanoparticles as an effective, eco‐friendly and recyclable solid acid catalyst were studied. PVA was used as the organic matrix which is the dispersing agent and acted as a template for the nanoparticle. It seems H‐bonds between ZP and PVA along polymer chains play an important role in the better dispersion of in situ formed ZP. The catalyst was characterized by several instrumental techniques such as BET, ICP‐OES, XRD, FT‐IR, SEM and TEM. The TPD‐NH3 analysis suggests the presence of reasonable amount of Brönsted acid sites. The acidic properties of catalyst were studied in acetylation of phenols by acetic anhydride (AA), specifically synthesis of acetylsalicylic acid (ASA), commonly known as Aspirin, from salicylic acid (SA). The effects of reaction time, reaction temperature, mole ratio of reactants, as well as amount of catalysts on the synthesis of ASA were investigated, and the reaction conditions were therefore optimized. The excellent yield (96%) of the ASA was obtained under optimized reaction conditions. The catalyst was recovered from reaction media and reused for 4 times after that with a consistent high yield.
To drain or not to drain elective uncomplicated laparoscopic cholecystectomy? A systematic review and meta‐analysis
Authors: Bugiantella Walter , Vedovati Maria Cristina , Becattini Cecilia , Canger Ruben Carlo Balzarotti , Avenia Nicola , Rondelli Fabio
Published: June 2014

Laparoscopic cholecystectomy (LC) has largely replaced conventional cholecystectomy in the past decade. However, there are still limited data about the value of prophylactic sub‐hepatic drainage for elective uncomplicated LC. We carried out a systematic review of the literature in order to perform a meta‐analysis about this issue. An unrestricted search in MEDLINE, EMBASE and Cochrane Library up to 31 December 2013 was performed. Overall, seven high‐methodological quality randomized controlled trials (RCTs) were included in the meta‐analysis, resulting in 1310 patients totally. The incidence of abdominal collections, wound infection and overall mortality according to the presence or absence of the sub‐hepatic drainage were meta‐analyzed. Sub‐hepatic drainage showed an increase in the abdominal collection rate in patients who underwent elective uncomplicated LC (OR 1.56, 95% CI 1.00–2.43) if compared to patients without drainage. A non‐significant correlation was found in overall mortality and infection rates. The meta‐analysis shows that the presence of the sub‐hepatic drainage does not reduce the incidence of abdominal collection after uncomplicated LC, whereas it does not influence wound infection and mortality rates, postoperative pain and hospital stay.
Aversive conditioning of Steller's Jays to improve marbled murrelet nest survival
Authors: Gabriel Pia O. , Golightly Richard T.
Published: June 2014

Predation on eggs of marbled murrelets (Brachyramphus marmoratus) has been linked to poor recruitment of young, especially in California, Oregon, and Washington. Corvids have been implicated as the most influential egg predators on murrelets. Remnant murrelet nesting habitats in California and elsewhere support a high population density of opportunistic corvids like the Steller's jay (Cyanocitta stelleri). We exposed Steller's jays to eggs mimicking murrelet eggs in color and size that contained the emetic carbachol. In laboratory tests, we effectively induced aversive conditioning subsequent to exposure to the murrelet‐mimic eggs. Attack latencies on murrelet‐mimic eggs increased following exposure to carbachol eggs and the strength of aversion was consistent over the range of retention periods tested (8 weeks). We conducted field trials on murrelet‐mimic eggs and control eggs deployed across a systematic 428‐ha grid in murrelet breeding habitat. After a period of aversive conditioning, the percentage of murrelet‐mimic eggs that were attacked by corvids in the field experiment was reduced by at least 37% in comparison to control eggs. We concluded that corvid predation can be reduced significantly using aversive training in the field, and could be practically applied to jay territories within murrelet breeding habitat. We suggest that aversive conditioning treatment may be a cost‐effective emergency tool to improve reproductive success of murrelets in the Pacific Northwest. © 2014 The Wildlife Society.
Protease‐Sensitive PEG Hydrogels Regulate Vascularization In Vitro and In Vivo
Authors: Vigen Marina , Ceccarelli Jacob , Putnam Andrew J.
Published: June 2014

Forming functional blood vessel networks in engineered or ischemic tissues is a significant scientific and clinical hurdle. Poly(ethylene glycol) (PEG)‐based hydrogels are adapted to investigate the role of mechanical properties and proteolytic susceptibility on vascularization. Four arm PEG vinyl sulfone is polymerized by Michael‐type addition with cysteine groups on a slowly degraded matrix metalloprotease (MMP) susceptible peptide, GPQG↓IWGQ, or a more rapidly cleaved peptide, VPMS↓MRGG. Co‐encapsulation of endothelial cells and supportive fibroblasts within the gels lead to vascular morphogenesis in vitro that is robust to changes in crosslinking peptide identity, but is significantly attenuated by increased crosslinking and MMP inhibition. Perfused vasculature forms from transplanted cells in vivo in all gel types; however, in contrast to the in vitro results, vascularization in vivo is not decreased in the more crosslinked gels. Collectively, these findings demonstrate the utility of this platform to support vascularization both in vitro and in vivo.
Protein Functionalization Revised: N‐tert‐butoxycarbonylation as an Elegant Tool to Circumvent Protein Crosslinking
Authors: Van Nieuwenhove Ine , Stubbe Birgit , Graulus Geert‐Jan , Van Vlierberghe Sandra , Dubruel Peter
Published: June 2014

The protection of primary amines available in proteins holds great potential to introduce a plethora of diverse functionalities along the protein backbone (e.g., via its carboxylic acid or alcohol moieties) while circumventing the crosslinking issue using conventional approaches. This paper reports on a straightforward and efficient proof‐of‐concept including the chemoselective N‐tert‐butyloxycarbonylation of the primary amines in the protein gelatin (gel‐NH‐BOC), followed by introducing crosslinkable methacrylamide moieties. The reaction is performed successfully under relatively mild conditions (50 °C). Following selective protein functionalization, the deprotection is realized by adding a catalytic amount of an aqueous hydrogen chloride solution. The present communication illustrates the occurrence of a straightforward and selective deprotection procedure, which is typically required to circumvent the occurrence of acidic hydrolysis of the protein backbone. The results hold promise for a large range of biomedical applications in which the presence of primary amines is essential for preserving the biological activity.

image
Facile “Living” Radical Polymerization of Methyl Methacrylate in the Presence of Iniferter Agents: Homogeneous and Highly Efficient Catalysis from Copper(II) Acetate
Authors: Jiang Hongjuan , Zhang Lifen , Jiang Xiaowu , Bao Xiaoguang , Cheng Zhenping , Zhu Xiulin
Published: June 2014

A facile homogeneous polymerization system involving the iniferter agent 1‐cyano‐1‐methylethyl diethyldithiocarbamate (MANDC) and copper(II) acetate (Cu(OAc)2) is successfully developed in bulk using methyl methacylate (MMA) as a model monomer. The detailed polymerization kinetics with different molar ratios (e.g., [MMA]0/[MANDC]0/[Cu(OAc)2]0 = 500/1/x (x = 0.1, 0.2, 0.5, 1.0)) demonstrate that this system has the typical “living”/controlled features of “living” radical polymerization, even with ppm level catalyst Cu(OAc)2, first order polymerization kinetics, a linear increase in molecular weight with monomer conversion and narrow molecular weight distributions for the resultant PMMA. 1H NMR spectra and chain‐extension experiments further confirm the “living” characteristics of this process. A plausible mechanism is discussed.

image
Glucose‐Sensitive QCM‐Sensors Via Direct Surface RAFT Polymerization
Authors: Sugnaux Caroline , Klok H.‐A
Published: June 2014

Thin, phenylboronic acid‐containing polymer coatings are potentially attractive sensory layers for a range of glucose monitoring systems. This contribution presents the synthesis and properties of glucose‐sensitive polymer brushes obtained via surface RAFT polymerization of 3‐methacrylamido phenylboronic acid (MAPBA). This synthetic strategy is attractive since it allows the controlled growth of PMAPBA brushes with film thicknesses of up to 20 nm via direct polymerization of MAPBA without the need for additional post‐polymerization modification or deprotection steps. QCM‐D sensor chips modified with a PMAPBA layer respond with a linear change in the shift of the fundamental resonance frequency over a range of physiologically relevant glucose concentrations and are insensitive toward the presence of fructose, thus validating the potential of these polymer brush films as glucose sensory thin coatings.

image
Random Material's Characteristics to Study Fluid‐Structure Interaction
Authors: Mansouri Mohamed , Radi Bouchaib , El Hami Abdelkhalak , Saouab Abdelghani
Published: June 2014

In many situations, the vibrating structures are in contact with a fluid (fluid around the hulls of a boat, reservoirs, heat exchangers in power plants, etc.), but the dynamic behavior of the structure can be significantly modified by the presence of the fluid. The sizing must take into account the effects of fluid‐structure interaction. Traditionally, the study of mechanical systems fluid‐structure interaction is based on a deterministic approach where all the parameters used in the model are a fixed value. But it suffices to having conducted a few experimentations to realize that the limitations of such modeling. Hence it needs to take into accounts the uncertainty in the parameters of mechanical systems. This work proposes to take the characteristics of the structure and the fluid as random and shows the efficiency of such approach. The proposed numerical stochastic method of the modal synthesis extended to reliability study, based on FORM (First Order Reliability Method) and SORM (Second Order Reliability Method) approaches, for solving the large vibro‐acoustic problems. The numerical method used takes into account the uncertainties of the input parameters of the two domains. The application of the proposed method is performed on a boat propeller immersed in air and water. To validate the calculation process, the numerical study is compared to an experimental study.
The Usage of Methylsilicones in Radiation‐Chemical Protection of Concrete
Authors: Fainleib Aleksandr , Kolesnyk Denys , Sheinich Leonid , Sakhno Viktor
Published: June 2014

An influence of the atmosphere components on composite material such as concrete leads to the reduction of its strength and changes in its structure.

Having excluded water from a concrete body it is possible to slow down the processes of its corrosion essentially. Traditional waterproofing means have various components with different viscosity in their structure. When applying them on a porous structure of a cement stone chromotropic separation of a hydrophobisator with the loss of its efficiency occurs.

The impregnation of concrete by unsaturated organosiloxanes of low viscosity and their blends with dimethylsilyl and methylhydridesilyl oligomers followed by their irradiation induced curing have been studied.

Samples of modified cement stone and determination of their physical‐mechanical properties, namely compressive strength, waterproofness and frost resistance as well as an influence of impregnation on hydrophobisity of cement stone surface were obtained. Positive effect of the modification proposed on service properties and on durability of radiation‐chemically modified concrete was observed.
High‐Temperature Viscoelastic Relaxation in All‐Cellulose Composites
Authors: Duchemin Benoît J.C. , Staiger Mark P. , Newman Roger H.
Published: June 2014

All‐cellulose composites were prepared across a range of different crystallinities in order to examine relationships between phase composition and viscoelastic behaviour in the temperature range of 270 °C to 340 °C corresponding to the α1 mechanical relaxation. Composite films were prepared by partial dissolution of microcrystalline cellulose in a LiCl/N,N‐dimethylacetamide (LiCl/DMAc) solvent system using the film casting technique. Dynamic mechanical analysis showed two contributions to α1 relaxation, with tan δ maxima at 303 ± 2 °C and at approximately 325 °C. The height of the maximum or shoulder at 303 ± 2 °C decreased with increasing crystallinity, and was therefore assigned to molecular motion associated with chemical decomposition in non‐crystalline domains. The maximum at 325 °C was assigned to chemical decomposition in chains associated with the surfaces of crystalline domains. Composites with high crystallinity showed best retention of the dynamic storage modulus when tested at 300 °C.
RND transporters protect Corynebacterium glutamicum from antibiotics by assembling the outer membrane
Authors: Yang Liang , Lu Shuo , Belardinelli Juan , Huc‐Claustre Emilie , Jones Victoria , Jackson Mary , Zgurskaya Helen I.
Published: June 2014

Corynebacterium–Mycobacterium–Nocardia (CMN) group are the causative agents of a broad spectrum of diseases in humans. A distinctive feature of these Gram‐positive bacteria is the presence of an outer membrane of unique structure and composition. Recently, resistance–nodulation–division (RND) transporters (nicknamed MmpLs, Mycobacterial membrane protein Large) have emerged as major contributors to the biogenesis of the outer membranes in mycobacteria and as promising drug targets. In this study, we investigated the role of RND transporters in the physiology of Corynebacterium glutamicum and analyzed properties of these proteins. Our results show that in contrast to Gram‐negative species, in which RND transporters actively extrude antibiotics from cells, in C. glutamicum and relatives these transporters protect cells from antibiotics by playing essential roles in the biogenesis of the low‐permeability barrier of the outer membrane. Conditional C. glutamicum mutants lacking RND proteins and with the controlled expression of either NCgl2769 (CmpL1) or NCgl0228 (CmpL4) are hypersusceptible to multiple antibiotics, have growth deficiencies in minimal medium and accumulate intracellularly trehalose monocorynomycolates, free corynomycolates, and the previously uncharacterized corynomycolate‐containing lipid. Our results also suggest that similar to other RND transporters, Corynebacterial membrane proteins Large (CmpLs) functions are dependent on a proton‐motive force.
A Bayesian model averaging approach to examining changes in quality of life among returning Iraq and Afghanistan Veterans
Authors: Stock Eileen M. , Kimbrel Nathan A. , Meyer Eric C. , Copeland Laurel A. , Monte Ralph , Zeber John E. , Gulliver Suzy Bird , Morissette Sandra B.
Published: June 2014

Many Veterans from the conflicts in Iraq and Afghanistan return home with physical and psychological impairments that impact their ability to enjoy normal life activities and diminish their quality of life (QoL). The present research aimed to identify predictors of QoL over an eight‐month period using Bayesian model averaging (BMA), which is a statistical technique useful for maximizing power with smaller sample sizes. A sample of 117 Iraq and Afghanistan Veterans receiving care in a southwestern health care system was recruited, and BMA examined the impact of key demographics (e.g. age, gender), diagnoses (e.g. depression), and treatment modalities (e.g. individual therapy, medication) on QoL over time. Multiple imputation based on Gibbs sampling was employed for incomplete data (6.4% missingness). Average follow‐up QoL scores were significantly lower than at baseline (73.2 initial versus 69.5 four‐month and 68.3 eight‐month). Employment was associated with increased QoL during each follow‐up, while post‐traumatic stress disorder and Black race were inversely related. Additionally, predictive models indicated that depression, income, treatment for a medical condition, and group psychotherapy were strong negative predictors of four‐month QoL but not eight‐month QoL. Copyright © 2014 John Wiley & Sons, Ltd.
Quantitative determination and validation of avermectin B1a in commercial products using quantitative nuclear magnetic resonance spectroscopy
Authors: Hou Zhuoni , Liang Xianrui , Du Liping , Su Feng , Su Weike
Published: June 2014

Nuclear magnetic resonance is defined as a quantitative spectroscopic tool that enables a precise determination of the number of substances in liquids as well as in solids. There is few report demonstrating the application of NMR in the quantification of avermectin B1a (AVB1a); here, a proton nuclear magnetic resonance spectroscopy (1H NMR) using benzene [1‐methoxy‐4‐(2‐nitroethyl) (PMN)] as an internal standard and deuterochloroform as an NMR solvent was tested for the quantitative determination of AVB1a. The integrated signal of AVB1a at 5.56 ppm and the signal of PMN at 8.14 ppm in the 1H NMR spectrum were used for quantification purposes. Parameters of specificity, linearity, accuracy, precision, intermediate precision, range, limit of detection (LOD), limit of quantification (LOQ), stability and robustness were validated. The established method was accurate and precise with good recovery (98.86%) and relative standard deviation (RSD) of assay (0.34%) within the linearity of the calibration curve ranging from 5.08 to 13.58 mg/ml (R2 = 0.9999). The LOD and LOQ were 0.009 and 0.029 mg/ml, which indicated the excellent sensitivity of the method. The stability of the method was testified by a calculated RSD of 0.11%. The robustness was testified by modification of four different parameters, and the differences among each parameter were all less than 0.1%. Comparing with the assay described by the manufacturer of avermectin tablets, there was no significant difference between the assay obtained by HPLC and quantitative NMR (qNMR), which indicated qNMR was a simple and efficient method for the determination of AVB1a in commercial formulation products. Copyright © 2014 John Wiley & Sons, Ltd.
A finite element method with mesh‐separation‐based approximation technique and its application in modeling crack propagation with adaptive mesh refinement
Authors: Ling Daosheng , Bu Lingfang , Tu Fubin , Yang Qingda , Chen Yunmin
Published: June 2014

This paper presents a FEM with mesh‐separation‐based approximation technique that separates a standard element into three geometrically independent elements. A dual mapping scheme is introduced to couple them seamlessly and to derive the element approximation. The novel technique makes it very easy for mesh generation of problems with complex or solution‐dependent, varying geometry. It offers a flexible way to construct displacement approximations and provides a unified framework for the FEM to enjoy some of the key advantages of the Hansbo and Hansbo method, the meshfree methods, the semi‐analytical FEMs, and the smoothed FEM. For problems with evolving discontinuities, the method enables the devising of an efficient crack‐tip adaptive mesh refinement strategy to improve the accuracy of crack‐tip fields. Both the discontinuities due to intra‐element cracking and the incompatibility due to hanging nodes resulted from the element refinement can be treated at the elemental level. The effectiveness and robustness of the present method are benchmarked with several numerical examples. The numerical results also demonstrate that a high precision integral scheme is critical to pass the crack patch test, and it is essential to apply local adaptive mesh refinement for low fracture energy problems. Copyright © 2014 John Wiley & Sons, Ltd.
A regularized phenomenological multiscale damage model
Authors: Liu Yang , Filonova Vasilina , Hu Nan , Yuan Zifeng , Fish Jacob , Yuan Zheng , Belytschko Ted
Published: June 2014

We present a regularized phenomenological multiscale model where elastic properties are computed using direct homogenization and subsequently evolved using a simple three‐parameter orthotropic continuum damage model. The salient feature of the model is a unified regularization framework based on the concept of effective softening strain. The unified regularization scheme has been employed in the context of constitutive law rescaling and the staggered nonlocal approach. We show that an element erosion technique for crack propagation when exercised with one of the two regularization schemes (1) possesses a characteristic length, (2) is consistent with fracture mechanics approach, and (3) does not suffer from pathological mesh sensitivity. Copyright © 2014 John Wiley & Sons, Ltd.
Synthesis and Photochromic Properties of Configurationally Varied Azobenzene Glycosides
Authors: Chandrasekaran Vijayanand , Johannes Eugen , Kobarg Hauke , Sönnichsen Frank D. , Lindhorst Thisbe K.
Published: June 2014

Invited for this months cover is the group of Prof. Thisbe K. Lindhorst from Christiana Albertina University of Kiel, Germany. The cover picture shows the principal structures of the azobenzene glycosides, which were synthesized in this work using glycosylation for preparation of the 1,2‐trans glycosides and Mills reaction for azobenzene coupling (as indicated by the retrosynthetic pair of scissors). Irradiation of these glycoconjugates effects­ E→Z isomerization of the azobenzene N=N double bond, thus causing a significant change of the relative spatial orientation of the conjugated sugar moiety. The photochromic properties of these ‘sweet switches’ were systematically investigated. For more details, see the Full Paper on 10.1002/open.201402010 (p. 99 ff.)
Synthesis, characterization, and organic field‐effect transistors study of conjugated D–A copolymers based on dialkylated naphtho[1,2‐b:5,6‐b′]dithiophene/naphtho[1,2‐b:5,6‐b′]difuran and benzodiathiazole/benzoxadiazole
Authors: Shi Shaowei , Shi Keli , Chen Song , Qu Rui , Wang Liwei , Wang Meng , Yu Gui , Li Xiaoyu , Wang Haiqiao
Published: June 2014

In this report, four donor–acceptor copolymers, P(NDT3‐BT), P(NDT3‐BO), P(NDF3‐BT), and P(NDF3‐BO), using 5,10‐didodecyl‐naphtho[1,2‐b:5,6‐b′]dithiophene (NDT3) or 5,10‐didodecyl‐naphtho[1,2‐b:5,6‐b′]difuran (NDF3) as an electron‐rich unit and benzodiathiazole (BT) or benzoxadiazole (BO) as an electron‐deficient one, were designed, synthesized, and characterized. Detailed systematical investigation was developed for studying the effect of the S/O atoms on the optical, electrochemical, and morphological properties of the polymers, as well as the subsequent performance of the organic field‐effect transistors (OFETs) fabricated from these copolymers. It was found that, compared with NDF3‐based P(NDF3‐BT)/P(NDF3‐BO), by replacing NDF3 with stronger aromatic NDT3, the resultant P(NDT3‐BT)/P(NDT3‐BO) show smaller lamellar distance with an increased surface roughness in solid state, and relatively higher hole mobilities are obtained. The hole mobilities of the four polymers based on OFETs varied from 0.20 to 0.32 cm2 V−1 s−1 depending on their molecular structures, giving some valuable insights for the further design and development of a new generation of semiconducting materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2465–2476
ɛ‐caprolactone and lactide polymerization promoted by an ionic titanium(IV)/iron(III) polynuclear halo‐alkoxide
Authors: Egevardt Cristiano , Giese Siddhartha O. K. , da C. Santos Alan D. , Barison Andersson , de Sá Eduardo L. , Filho Arion Zandoná , da Silva Thiago A. , Zawadzki Sônia F. , Soares Jaísa F. , Nunes Giovana G.
Published: June 2014

The ionic [Ti3(µ3‐OPri)2(µ‐OPri)3(OPri)6][FeCl4] halo‐alkoxide (A) was investigated for its activity towards the bulk polymerization of rac‐lactide (rac‐LA) and ɛ‐caprolactone (ɛ‐CL) in various temperatures, monomer/A molar proportions, and reaction times. The reactivity of A in the ring‐opening polymerization (ROP) of both monomers is mainly due to the cationic [Ti3(OPri)11]+ unity and proceeds through the coordination–insertion mechanism. Molecular weights ranging from 6,379 to 13,950 g mol−1 and PDI values varying from 1.22 to 1.52 were obtained. Results of ROP kinetic studies for both ɛ‐CL and rac‐LA confirm that the reaction rates are first‐order with respect to monomers. The production of poly(ɛ‐caprolactone) shows a higher sensitivity of the reaction rate to temperature, while the polymerization of rac‐LA is slower and more dependent on the thermal stability of the active species during the propagation step. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2509–2517
Wilcoxon's signed‐rank statistic: what null hypothesis and why it matters
Authors: Li Heng , Johnson Terri
Published: June 2014

In statistical literature, the term ‘signed‐rank test’ (or ‘Wilcoxon signed‐rank test’) has been used to refer to two distinct tests: a test for symmetry of distribution and a test for the median of a symmetric distribution, sharing a common test statistic. To avoid potential ambiguity, we propose to refer to those two tests by different names, as ‘test for symmetry based on signed‐rank statistic’ and ‘test for median based on signed‐rank statistic’, respectively. The utility of such terminological differentiation should become evident through our discussion of how those tests connect and contrast with sign test and one‐sample t‐test. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.