bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surfactant Protein-A as an Anti-Inflammatory Component in the Amnion: Implications for Human Pregnancy
Authors: Lee Deug-Chan , Romero Roberto , Kim Chong Jai , Chaiworapongsa Tinnakorn , Tarca Adi L. , Lee JoonHo , Suh Yeon-Lim , Mazaki-Tovi Shali , Vaisbuch Edi , Mittal Pooja , Draghici Sorin , Erez Offer , Kusanovic Juan Pedro , Hassan Sonia S. , Kim Jung-Sun 
Published: May 2010

AbstractThe mechanism of mouse parturition is thought to involve myometrial infiltration by amniotic fluid (AF) macrophages, activated by surfactant protein-A (SP-A). In humans, the concentration of AF SP-A decreases during labor, and no fetal macrophages are found in the myometrium after labor. Therefore, it appears that the mechanisms of labor in mice and humans are different. We investigated a potential role for SP-A in human pregnancy and parturition by examining SP-A expression patterns in AF and amnion. High molecular mass (&gt;250 kDa) oligomeric SP-A was increased in AF with advancing gestation. Interestingly, these oligomers were more abundant in placental amnion before labor at term, while they increased primarily in reflected amnion during labor (p &lt; 0.05). Immunoblotting showed a binding of high molecular mass SP-A in AF to amnion. In C57BL/6 mice, oligomeric SP-A was also readily detected in AF from E15 onwards, but not in amnion. Macrophage density in mice myometrium did not change with advancing gestational age. Microarray analysis of human amnion explants incubated with SP-A revealed a molecular signature of inhibited cytokine–cytokine receptor interaction with downregulation of IL-1β, CXCL2, and CXCL5 mRNA expression. The findings in this study strongly suggest that SP-A signals amniotic anti-inflammatory response via AF during pregnancy. We propose that an SP-A interaction among AF, placental amnion, and reflected amnion is a unique mechanism for immunoregulation in human pregnancy akin to that established in lung biology. However, AF SP-A and fetal macrophages by themselves do not seem to be exclusive effectors of parturition in humans.
Transient elastography in the assessment of liver fibrosis in adult thalassemia patients
Authors: Fraquelli Mirella , Cassinerio Elena , Roghi Alberto , Rigamonti Cristina , Casazza Giovanni , Colombo Massimo , Massironi Sara , Conte Dario , Cappellini Maria Domenica 
Published: May 2010

AbstractTransient elastography (TE) is a valuable noninvasive technique of measuring liver stiffness and a reliable tool for predicting hepatic fibrosis in patients with chronic liver disease. The role of TE in patients with β‐thalassemia has not been extensively investigated. The present study aimed to evaluate the role of TE in the assessment of hepatic fibrosis in 115 adult patients with β‐thalassemia major (TM) (#59) or intermedia (TI) (#56). TE was performed according to current practice. Histologic data were obtained in 14 cases. Liver iron concentration was assessed by atomic absorption spectrometry and T2* magnetic resonance. In patients with TM, the proportion of anti‐HCV positive viremic patients, median serum ferritin levels, and TE values were significantly higher than in TI. In the group of 14 patients who underwent liver biopsy, a significant positive correlation was observed between liver stiffness and fibrosis stage (r = 0.73, P = 0.003). Severe fibrosis is diagnosed with a sensitivity of 60% and a specificity of 89%, whereas cirrhosis is detected with a sensitivity of 100% and a specificity of 92%. At multivariate analysis, the variables independently associated with TE were ALT, GGT, and bilirubin levels in both groups and, in patients with TM, HCV RNA positivity. In β‐thalassemia patients, TE is a reliable tool for assessing liver fibrosis even if the influence of iron overload has to be clarified. Am. J. Hematol. 85:564–568, 2010. © 2010 Wiley‐Liss, Inc.
Die Entstehung erster Zellen – von der Nährstoffaufnahme hin zur Verlängerung eingeschlossener Nucleotide
Authors: Meierhenrich Uwe J. , Filippi Jean‐Jacques , Meinert Cornelia , Vierling Pierre , Dworkin Jason P. 
Published: May 2010

AbstractEin neues Verständnis des Ursprungs des Lebens auf der Erde gründet sich auf jüngsten, bedeutenden Entdeckungen zur Biophysik von Membranen. Es wurde gezeigt, dass Vesikel aus Membran‐Doppelschichten eine facettenreiche Mikroumgebung zur Verfügung stellen, in der sich erste Stoffwechselreaktionen entwickelt haben können. Zellmembran‐ähnliche Aggregate amphiphiler Moleküle, die Oligonucleotide einschließen können, wurden erfolgreich im Labor hergestellt. Im Rahmen von Laborstudien zur Entstehung des Lebens gelang die Verlängerung eines DNA‐Primers im Inneren von Fettsäurevesikeln, sobald das extravesikuläre Medium mit aktivierten Nucleotiden versetzt wurde. Diese Studien zeigten, dass zellähnliche Vesikel durchlässig genug sein können, um geladene Moleküle wie aktivierte Nucleotide aufzunehmen, die sich wiederum im Protozellinneren am Kopieren von DNA‐Matrizen beteiligen. Wir fassen in diesem Aufsatz jüngste Experimente in diesem Bereich zusammen und beschreiben ein mögliches Szenario zum Ursprung erster primitiver Zellen, wobei wir der Verlängerung eingeschlossener Nucleotide besondere Aufmerksamkeit widmen.
On the Origin of Primitive Cells: From Nutrient Intake to Elongation of Encapsulated Nucleotides
Authors: Meierhenrich Uwe J. , Filippi Jean‐Jacques , Meinert Cornelia , Vierling Pierre , Dworkin Jason P. 
Published: May 2010

AbstractRecent major discoveries in membrane biophysics hold the key to a modern understanding of the origin of life on Earth. Membrane bilayer vesicles have been shown to provide a multifaceted microenvironment in which protometabolic reactions could have developed. Cell‐membrane‐like aggregates of amphiphilic molecules capable of retaining encapsulated oligonucleotides have been successfully created in the laboratory. Sophisticated laboratory studies on the origin of life now show that elongation of the DNA primer takes place inside fatty acid vesicles when activated nucleotide nutrients are added to the external medium. These studies demonstrate that cell‐like vesicles can be sufficiently permeable to allow for the intake of charged molecules such as activated nucleotides, which can then take part in copying templates in the protocell interior. In this Review we summarize recent experiments in this area and describe a possible scenario for the origin of primitive cells, with an emphasis on the elongation of encapsulated nucleotides.
Thermal effects on the percolation behavior of polyvinylidene fluoride/nickel composites
Authors: Panda M. , Thakur A. K. , Srinivas V. 
Published: May 2010

AbstractPercolation theory predicts the ideal percolation threshold (PC) for insulator/conductor composites (ICC) to be at 0.16 of the conductor volume fraction in the composite. In this article, we have investigated the percolation behavior in polyvinylidene fluoride/nickel (Ni) composites by varying the Ni concentration. It is observed that the thermal effect/time of heat treatment play a crucial role in changing the value of PC in a simple random continuum percolative ICC. The effect is attributed to decrease in: (i) intercluster distance, (ii) viscosity of the polymer, and (iii) wetting of the polymer to metal. The heat energy helps the polymer matrix to be melted as a result the metal particles/clusters come closure, that causes an increase in the cluster size of the metal particles. The overall effect is lowering of PC mainly due to decrease in intercluster distance. A drastic enhancement in the dielectric permittivity with increase of metal content is explained using boundary layer capacitive effect arising due to Maxwell–Wagner–Sillars interfacial polarization of accumulated charges at the metal–polymer interfaces and blocking of charge carriers at the insulating boundary. The substantial enhancement of ac conductivity at the PC is attributed to leakage of charge carriers across the insulating barrier. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
In‐line characterization of polypropylene nanocomposites using FT‐NIR
Authors: Witschnigg Andreas , Laske Stephan , Kracalik Milan , Feuchter Michael , Pinter Gerald , Maier Günther , Märzinger Wolfgang , Haberkorn Michael , Langecker Günter Rüdiger , Holzer Clemens 
Published: May 2010

AbstractThe morphology of polymer nanocomposites is usually characterized by various methods like X‐ray diffraction (XRD) or transmission electron microscopy (TEM). In this work, a new approach for characterizing nanocomposites is developed: the results of small angle x‐ray scattering, on‐line extensional rheometry (level of melt strength) and Young's modulus out of tensile test are correlated with those of near infrared (NIR) spectroscopy. The disadvantages of the common characterization methods are high costs and very time consuming sample preparation and testing. In contrast, NIR spectroscopy has the advantage to be measured in‐line and in real time directly in the melt. The results were obtained for different aggregate states (NIR spectroscopy and on‐line rheotens test in melt state, tensile test, and XRD in solid state). Therefore, important factors like crystallization could not be considered. Nevertheless, this work demonstrates that the NIR‐technology is perfectly suitable for quantitative in‐line characterization. The results show that, by the installation of a NIR spectrometer on a nanocomposite‐processing compounder, a powerful instrument for quality control and optimization of compounding process, in terms of increased and constant quality, is available. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Modification of halloysite nanotubes with poly(styrene–butyl acrylate–acrylic acid) via in situ soap‐free graft polymerization
Authors: Zhang Yanwu , Jiang Junqing , Liang Qihui , Zhang Bing 
Published: May 2010

AbstractHalloysite nanotubes (HNTs) were grafted with poly(styrene–butyl acrylate–acrylic acid) (P‐SBA) via an in situ soap‐free emulsion polymerization. To introduce double bonds into the HNTs, N‐(β‐aminoethyl)‐γ‐aminopropyl trimethoxysilane was first used to modify the HNTs and render amino groups, and then, the double bonds were anchored through an amidation reaction between acryloyl chloride and amino groups. P‐SBA chains were grafted onto HNTs because of participating of double bonds in the copolymerization of styrene, butyl acrylate, and acrylic acid. Fourier transforms infrared spectroscopy, transmission electron microscopy, specific surface area measurements, and thermogravimetric analysis were used to characterize the HNTs grafted with P‐SBA. The results indicate that 25.21% of P‐SBA was grafted onto the outer walls of the HNTs and filled into the inner spaces of the HNTs. The modification dramatically decreased the surface area of the HNTs. The property study of the HNTs grafted with P‐SBA focused on the dispersion behavior in the biphase system. The results show that the grafted HNTs dispersed stably in the water/cyclohexane biphase system and were a potential emulsifier. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
An effective antimicrobial treatment for wool using polyhexamethylene biguanide as the biocide, Part 1: Biocide uptake and antimicrobial activity
Authors: Gao Yuan , Cranston Robin 
Published: May 2010

AbstractAntimicrobial treatments of textiles have received substantial attention in recent years, both in academic research and in commercial productions. Such treatments prevent the odor formation and fabric deterioration that arise from the growth of microbes on the textiles during their use or storage. So far, antimicrobial treatments have mainly focused on cotton and synthetic fibers, and a viable treatment for wool is lacking. In this report, we demonstrate a novel and effective antimicrobial finishing for wool. We found that pretreatment with peroxymonosulfate and sulfite, a treatment previously developed for shrink resistance, uniquely enabled wool to exhaust up to 5% (on the weight of the fabric) of the biocide polyhexamethylene biguanide (PHMB) under mild conditions. In contrast, untreated or chlorinated wool had little affinity for this biocide. The exhaustion was facilitated by higher temperatures but was not affected by pH over a broad range. Wool fabrics finished with PHMB exhibited strong antimicrobial abilities that could deactivate the bacterium Escherichia
coli within a few minutes of contact. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Compatibilization method applied to the chitosan‐acid poly(L‐lactide) solution
Authors: Suyatma Nugraha Edhi , Copinet Alain , Coma Véronique , Fricoteaux Florence 
Published: May 2010

AbstractWe are testing the compatibilization of the chitosan/PLA blends by addition of diisocyanate and at studying the effect of several MDI concentrations (0.5 and 2.5% of the global blend mass, w/w). To evaluate the MDI efficiency as a compatibilizer of chitosan/PLA blends, we worked with the following methods: IRTF spectra with higher peak at 1558 cm−1 is due to the NH bonds that exist in urea and urethane, thermal properties shows that the temperature of the endothermic peaks of the chitosan/PLA blends with MDI is very close to the temperature of pure chitosane and SEM micrography shows that MDI addition decreases the PLA particles size in the chitosan mixture; they also comply with the compatibilization theory. After that the mechanical properties have been characterized: we can notice that the MDI compatibilized chitosan/PLA blends have a higher Young's modulus than the noncompatibilized blends. we are showed that the use of 0.5% MDI is not enough sufficient to obtain a compatibilization, because a part of the MDI can be consumed by water. The addition of MDI increases the performance of the mechanical properties of the blends. Therefore, with this compatibilization, we could obtain some chitosan/PLA blends that would be water‐resistant and that would also keep their mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Small angle neutron scattering study of structural aspects of nonionic surfactants (Tween 20 and Tween 80) in the presence of polyethylene glycols and triblock polymers
Authors: Mahajan Rakesh Kumar , Chawla Jyoti , Vohra Kulwinder Kumar , Aswal Vinod Kumar 
Published: May 2010

AbstractSmall angle neutron scattering (SANS) technique has been used to study the micellar behavior of nonionic surfactants, Tween 20 and Tween 80 with additives like polyethylene glycols (PEG with molecular mass 400, 6000, and 15,000) and triblock polymers (TBPs) of varying composition. Surfactant‐additive interactions have been explained on the basis of parameters like aggregation number (Nagg), core radius (Rc), hard sphere radius (Rhs), volume fraction (ϕ) and axial ratio (b/a). The SANS analysis indicate the reduction in values ofNaggof Tween on addition of PEG additive. Shape of Tweens (3 wt %) micelles in the presence of PEG (10 wt %) is found to oblate ellipsoidal. Similarly, the shape of Tween (3 wt %) micelles is oblate ellipsoidal at low concentration of TBPs (1 wt %); however, they become spherical as the concentration of TBP increases to 10 wt %. The shape of micelles of pure TBPs also comes out to be spherical. Results reflects that at low concentration of TBP shape is controlled by surfactant (Tween 20 and Tween 80) while at high concentration of TBP shape of mixed micelle is controlled by TBP. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of an aminated bagasse fiber and its mercury adsorption behavior
Authors: Ma Nianfang , Chen Shuixia , Liu Xilian , Yang Ying 
Published: May 2010

AbstractAn aminated bagasse (AB) with high‐adsorption capacity for mercury ions was prepared by grafting copolymerization of acrylonitrile onto sugarcane bagasse, followed by aminating with chelating molecule diethylenetriamine. Effects of grafting conditions such as irradiation dosage, acrylonitrile concentration, and solvents on the grafting yield were investigated. The adsorption performance for mercury ions were evaluated by batch adsorption experiments and kinetic experiments. The results show that AB is effective for the removal of mercury over a wide range of pH > 5. Adsorption isotherms of mercury ions on the modified bagasse can be well described by Langmuir equation. The equilibrium adsorption amount could be as high as 917.4 mg/g, and the removal percent of mercury ions can achieve 99%. The kinetic adsorption results indicate that AB could remove 80% of mercury ions in 2 h and 24 more hours are needed to achieve adsorption equilibrium. Regeneration experiments show that the adsorption capacity of recycled AB still can reach the level of 96% after four cycles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of photo‐reactive azidophenyl chitosan derivative for immobilization of growth factors
Authors: Kim Kwang‐Il , Lee Jae‐Woo , Ito Yoshihiro , Kang Jeong‐Hwa , Song Kwang‐Sup , Jang Eui‐Chan , Son Tae‐Il 
Published: May 2010

AbstractPhotoreactable chitosan derivative have been prepared by introducing azido phenyl groups to amino groups of low molecular weight chitosan to facilitate the immobilization of growth factors. The prepared azidophenyl chitosan was characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), scanning electron microscope (SEM). Cytotoxicity of prepared azidophenyl chitosan derivative was confirmed by MTT assay. Cell culture on the surfaces coated azidophenyl chitosan derivative was also carried out and cell adhesion was observed between azidophenyl chitosan derivative and cells. And the released rate of protein from azidophenyl chitosan derivative was measured using albumin instead of growth factors for check on effect of the prepared azidophenyl chitosan derivative. As a result of that, relations among the concentration of azidophenyl chitosan derivative, releasing period of albumin and the quantity of released albumin was confirmed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of geometrical parameters of screw melt mixing on visco‐elastic properties of PC/ABS blends
Authors: Hausnerová Berenika , Kitano Takeshi , Kuthanová Vanda , Sáha Petr 
Published: May 2010

AbstractIn the present article, we describe an experimental study of blends of polycarbonate (PC) with acrylonitrile‐butadiene‐styrene graft copolymer (ABS) melt mixed in two types of single screw (varying in compression ratio) and twin screw (counter and co‐rotational) extruders. The effect of screw design variation is qualified via storage and loss moduli differences obtained for particular screw geometries. Rotational rheometer with parallel‐plates geometry was used to determine dynamic viscoelastic properties at a strain of 1% selected as the value representative of the linear viscoelasticity. Measurements were carried out at 220, 240, and 260°C and angular frequencies in the range from 0.1 to 100 rad/s. Regardless of the dependences variation with blend compositions, mixing performed on the extruder with counter rotating twin screws resulted in the lowest viscoelastic response in the whole range investigated. The rheological observations were confirmed by the results of SEM analysis. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Multi‐offset ground penetrating radar methods to image buried foundations of a medieval town wall, Great Yarmouth, UK
Authors: Booth Adam D. , Clark Roger A. , Hamilton Ken , Murray Tavi 
Published: May 2010

AbstractIn conventional common‐offset (CO) usage, ground‐penetrating radar (GPR) methods may be problematic where a target is hosted within a structurally complex subsurface, or where coherent noise energy obscures the response to that target. This often occurs when imaging archaeology in urban environments, where reflected and diffracted air‐wave energy can be pervasive in the presence of cars, walls and other nearby features. To overcome such issues we show a multi‐offset (MO) GPR approach to urban surveying. Multi‐offset velocity analysis is used as a filter by which ground‐propagating signal energy is separated from airborne arrivals, with the latter suppressed on application of normal moveout corrections and stacking. Pre‐stack migration is applied and yields considerable improvement to target resolution compared with post‐stack routines. The MO‐derived model of GPR velocity can also show the subsurface distribution of archaeological layering. Methods are demonstrated for a 25‐fold MO GPR profile acquired, using unshielded antennas of 200 MHz centre‐frequency, over foundations of the medieval town wall of Great Yarmouth, UK. The buried foundations represent a vertical discontinuity in the ground, which truncates both natural geological and archaeologically prospective layers. In addition to this complex geometry, which itself hinders GPR imaging, coherent air‐wave noise is problematic because there are numerous above‐surface features (e.g. parked cars, above‐surface walls) in the immediate vicinity of the profile. The improvement offered by MO techniques is benchmarked against a conventional CO routine and compared with co‐located borehole records for a comprehensive subsurface interpretation. Target foundations appear ca. 1.5 m beneath the ground surface, and GPR data support artefactual evidence of the construction of a sixteenth century rampart on their interior side. Despite the increased survey effort, we recommend MO methods at any location where CO data are dominated with coherent noise energy, and where complex subsurface geometries degrade the output from standard migration algorithms. Copyright © 2010 John Wiley & Sons, Ltd.
Heck‐Type Reactions of Imine Derivatives: A DFT Study
Authors: Li Zhe , Fu Yao , Zhang Song‐Lin , Guo Qing‐Xiang , Liu Lei 
Published: May 2010

AbstractThe mechanism of a recently discovered intramolecular Heck‐type coupling of oximes with aryl halides (Angew. Chem. Int. Ed. 2007, 46, 6325) was systematically studied by using density functional methods enhanced with a polarized continuum solvation model. The overall catalytic cycle of the reaction was found to consist of four steps: oxidative addition, migratory insertion, β‐H elimination, and catalyst regeneration, whereas an alternative base‐promoted CH activation pathway was determined to be less favorable. Migratory insertion was found to be the rate determining step in the catalytic cycle. The apparent activation barrier of migratory insertion of the (E)‐oxime was +20.5 kcal mol−1, whereas the barrier of (Z)‐oxime was as high as +32.7 kcal mol−1. However, (Z)‐oxime could isomerize to form the more active (E)‐oxime with the assistance of K2CO3, so that both the (E)‐ and (Z)‐oxime substrates could be transformed to the desired product. Our calculations also indicated that the Z product was predominant in the equilibrium of the isomerization of the imine double bond, which constituted the reason for the good Z‐selectivity observed for the reaction. Furthermore, we examined the difference between the intermolecular Heck‐type reactions of imines and of olefins. It was found that in the intermolecular Heck‐type coupling of imines, the apparent activation barrier of migratory insertion was as high as +35 kcal mol−1, which should be the main obstacle of the reaction. The analysis also revealed the main problem for the intermolecular Heck‐type reactions of imines, which was that the breaking of a CN π bond was much more difficult than the breaking of a CC π bond. After systematic examination of a series of substituted imines, (Z)‐N‐amino imine and N‐acetyl imine were found to have relatively low barriers of migratory insertion, so that they might be possible substrates for intermolecular Heck‐type coupling.