bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of mechanical properties of PP/Nanoclay/CaCO3 ternary nanocomposite using response surface methodology
Authors: Zare Yasser , Garmabi Hamid , Sharif Farhad 
Published: July 2011

AbstractResponse surface method of experimental design was applied to optimize the mechanical properties of polypropylene (PP)/nanoclay/CaCO3 hybrid ternary nanocomposite using three different levels of melt flow index (MFI) of PP, nanoclay, and CaCO3 contents. The samples were prepared by melt mixing in a lab scale corotating twin screw extruder. The main effect of each parameter on the tensile modulus, tensile strength, and impact strength was extensively discussed. The structure of obtained nanocomposite was studied using X‐ray diffraction (XRD), atomic force microscopy (AFM), and scanning electron microscopy (SEM) techniques. Tensile modulus and impact resistance of prepared ternary nanocomposite were correlated to considered parameters using a second‐order polynomial model. Also, the optimum values of studied variables were determined using contour plots. The obtained results show that increasing the nanoclay and CaCO3 contents improve the tensile modulus up to 45%, whereas the optimum value of impact strength, about 54%, is achieved at low concentrations of nanoclay (2 wt %) and CaCO3 (8 wt %). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The association between hip morphology parameters and nineteen‐year risk of end‐stage osteoarthritis of the hip: A nested case–control study
Authors: Nicholls Alex S. , Kiran Amit , Pollard Thomas C. B. , Hart Deborah J. , Arden Charlotte P. A. , Spector Tim , Gill H. S. , Murray David W. , Carr Andrew J. , Arden Nigel K. 
Published: July 2011

AbstractObjectiveSubtle deformities of the hip joint are implicated in the etiology of osteoarthritis (OA) of the hip. Parameters that quantify these deformities may aid understanding of these associations. We undertook this study to examine relationships between such parameters and the 19‐year risk of total hip arthroplasty (THA) for end‐stage OA.MethodsA new software program designed for measuring morphologic parameters around the hip was developed and validated in a reliability study. THA was the outcome measure for end‐stage OA. A nested case–control study was used with individuals from a cohort of 1,003 women who were recruited at year 1 in 1989 and followed up to year 20 (the Chingford Study). All hips with THA by year 20 and 243 randomly selected control hips were studied. Pelvis radiographs obtained at year 2 were analyzed for variations in hip morphology. Measurements were compared between the THA case group and the control group.ResultsPatients with THA had a higher prevalence of cam deformity than did their respective controls (median alpha angle 62.4° versus 45.8° [P = 0.001]; mean modified triangular index height 28.5 mm versus 26.9 mm [P = 0.001]) as well as a higher prevalence of acetabular dysplasia (mean lateral center edge angle 29.5° versus 34.3° [P = 0.001]; median extrusion index 0.25 versus 0.185 [P = 0.009]). Logistic regression analyses clustering by subject and adjusting for radiographic hip OA at year 2 showed that these morphologic parameters were still significantly associated with THA by year 20. The alpha angle and lateral center edge angle predicted the risk of THA independently when included in the same model.ConclusionThis investigation describes measurements that predict the risk of THA for end‐stage OA by year 20, independently of the presence of radiographic hip OA at year 2. These measurements can be made on an anteroposterior pelvis radiograph, which is an inexpensive and commonly used clinical method of investigation.
Phosphine‐Catalyzed [4+2] Annulations of 2‐Alkylallenoates and Olefins: Synthesis of Multisubstituted Cyclohexenes
Authors: Tran Yang S. , Martin Tioga J. , Kwon Ohyun 
Published: July 2011

AbstractFrom our investigations on phosphine‐catalyzed [4+2] annulations between α‐alkyl allenoates and activated olefins for the synthesis of cyclohexenes, we discovered a hexamethylphosphorous triamide (HMPT)‐catalyzed [4+2] reaction between α‐alkyl allenoates1and arylidene malonates or arylidene cyanoacetates2that provides highly functionalized cyclohexenes3and4in synthetically useful yields (30–89 %), with moderate to exclusive regioselectivity, and reasonable diastereoselectivity. Interestingly, the [4+2] annulations between the α‐alkyl allenoates1and the olefins2manifested a polarity inversion of the 1,4‐dipole synthon1, depending on the structure of the olefin, thus providing cyclohexenes3exclusively when using arylidene cyanoacetates. The polarity inversion of α‐alkyl allenoates from a 1,4‐dipoleAtoBunder phosphine catalysis can be explained by an equilibrium between the phosphonium dienolateCand the phosphorous ylideD.
Determination of trace carvedilol by solid substrate–room temperature phosphorimetry, based on its activating effect on hypochlorite‐oxidizing amaranth using sodium dodecyl benzene sulphonate as sensitizer
Authors: Liu Jia‐Ming , Lin Shao‐Qin , Lin Xuan , Zeng Li‐Qing , Huang Xiao‐Mei 
Published: July 2011

ABSTRACTThis work proposes a simple and sensitive solid substrate–room temperature phosphorimetry (SS–RTP) for the selective determination of carvedilol (CV). The method is based on the sensitizing effect of sodium dodecyl benzene sulphonate (SDBS) on CV to activate the oxidation between NaClO and amaranth, resulting in the intense quenching of room temperature phosphorescence (RTP) of the system. Compared with non‐SDBS system, the reduction of phosphorescence intensity (ΔIp) with SDBS is 16.5 times higher and is directly proportional to the content of CV, covering a wide range 0.080–16.00 fg/spot. The regression equation of the working curve can be expressed as ΔIp = 0.7780 + 7.057 mCV (fg/spot) (correlation coefficient (r) = 0.9976, n = 8), with a detection limit (LD) of 0.020 fg/spot (corresponding concentration is 5.1 × 10−14 g/mL, sample volume is 0.40 μL/spot). This sensitive method has also been applied to determine trace CV in human plasma and the results agreed with synchronous fluorimetry (SF). The activation energy (E) and rate constant (k) of this activating reaction were 69.04 kJ/mol and 3.580 × 10−4 s−1, respectively. The reaction mechanism is also discussed. Copyright © 2011 John Wiley & Sons, Ltd.
Clinical anatomy of the coccyx: A systematic review
Authors: Woon Jason T.K. , Stringer Mark D. 
Published: July 2011

AbstractThe coccyx has been relatively neglected in anatomical research which is surprising given the population prevalence of coccydynia and our inadequate understanding of its etiology. This systematic review analyzes available information on the clinical anatomy of the coccyx. A literature search using five electronic databases and standard anatomy reference texts was conducted yielding 61 primary and 7 secondary English‐language sources. This was supplemented by a manual search of selected historical foreign language articles. The coccygeal vertebrae, associated joints, ligaments and muscles, coccygeal movements, nerves, and blood supply were analyzed in detail. Although the musculoskeletal aspects of the coccyx are reasonably well described, the precise anatomy of the coccygeal plexus and its distribution, the function of the coccygeal body, and the anatomy of the sacrococcygeal zygapophyseal joints are poorly documented. Further research into the anatomy of the coccyx may clarify the etiopathogenesis of coccydynia which remains uncertain in one‐third of affected patients. Clin. Anat. 25:158–167, 2012. © 2011 Wiley‐Liss, Inc.
Ischaemia‐modified albumin levels in newborn jaundice before and after phototherapy
Authors: Erdem S. S. , Kurban S. , Altunhan H. , Annagür A. , Örs R. , Yerlikaya F. H. , Gökçe R. , Mehmetoğlu İ. 
Published: July 2011

The aim of our study was to assess the effect of phototherapy (PT) on ischaemia‐modified albumin (IMA) and malondialdehyde (MDA) levels in hyperbilirubinemic full‐term newborns. The study was performed on 36 full‐term infants exposed to PT. The babies were aged 3 to 13 days. IMA and MDA levels of the babies were determined before and after PT, by a colorimetric assay. IMA levels before and after PT were found as 0.424 ± 0.290 and 0.531 ± 0.262 absorbance units, respectively. Although IMA levels after PT were slightly higher, the difference was not statistically significant (p > 0.131). MDA levels before and after PT were found as 8.4 ± 1.8 µmol/l and 9.4 ± 1.5 µmol/l, respectively. Serum MDA concentrations were significantly higher after PT than before PT (p < 0.000). In previous studies, conflicting findings have been reported about the effect of PT on oxidant and antioxidant systems. However, we have found no study investigating IMA levels in hyperbilirubinaemia in newborns before and after PT.Our results shows that PT does not affect IMA levels significantly. IMA increases as a result of oxidative stress. We believe that the lack of significant difference between our IMA levels before and after PT may resulted from hyperbilirubinaemia, which has antioxidant effect. Copyright © 2011 John Wiley & Sons, Ltd.
Peptide‐Functionalized Luminescent Iridium Complexes for Lifetime Imaging of CXCR4 Expression
Authors: Kuil Joeri , Steunenberg Peter , Chin Patrick T. K. , Oldenburg Joppe , Jalink Kees , Velders Aldrik H. , van Leeuwen Fijs W. B. 
Published: July 2011

AbstractThe chemokine receptor 4 (CXCR4) is over‐expressed in 23 types of cancer in which it plays a role in, among others, the metastatic spread. For this reason it is a potential biomarker for the field of diagnostic oncology. The antagonistic Ac‐TZ14011 peptide, which binds to CXCR4, has been conjugated to luminescent iridium dyes to allow for CXCR4 visualization. The iridium dyes are cyclometalated octahedral iridium(III) 2‐phenylpyridine complexes that can be functionalized with one, two or three targeting Ac‐TZ14011 peptides. Confocal microscopy and fluorescence lifetime imaging microscopy (FLIM) showed that the peptide–iridium complex conjugates can be used to visualize CXCR4 expression in tumor cells. The CXCR4 receptor affinity and specific cell binding of the mono‐, di‐ and trimeric peptide derivatives were assessed by using flow cytometry. The three derivatives possessed nanomolar receptor affinity and could distinguish between cell lines with different CXCR4 expression levels. This yields the first example of a neutral iridium(III) complex functionalized with peptides for FLIM‐based visualization of a cancer associated membrane receptor.
Purification of C9 Arenes by Stripping Crystallization
Authors: Shiau L.‐D. , Lai M.‐H. , Liu K.‐F. 
Published: July 2011

AbstractA new separation technique called stripping crystallization (SC) is applied for purification of a mesitylene/pseudoumene mixture. SC combines distillation and crystallization to produce pure crystals due to the three‐phase equilibrium. The experiments demonstrate that a batch SC operation can purify pseudoumene from 85 % to 95 % for the pseudoumene‐rich mixture with a recovery rate of 51 % while it can only purify mesitylene from 85 % to 88 % for the mesitylene‐rich mixture with a recovery rate of 34 %. Compared to azeotropic distillation, SC is a clean separation technology as no chemicals are added. SC can be continued until the liquid phase is completely eliminated and only pure crystals remain in the feed. Compared to conventional crystallization, filtration or centrifugation is not needed to separate the solid crystals from the mother liquor since no mother liquor is present together with the crystals. In addition, crystal washing is not required since no impurities adhere to the crystal surfaces at the end of operation.
Lanthanide Ion Extraction by Trifluoromethyl‐1,3‐diketonate‐Functionalised Ionic Liquids Adsorbed on Silica
Authors: Olivier Jean‐Hubert , Camerel Franck , Ziessel Raymond 
Published: July 2011

AbstractWhile acetylacetone (acacH) derivatives are, upon deprotonation, ubiquitous ligands in coordination chemistry, their potential to form stable ionic liquids has not been studied so far. Here we describe a straightforward synthesis of novel trifluoroacetylacetone‐functionalised imidazolium salts. These salts are built from an imidazolium ring substituted on one side with a flexible chain of fixed length carrying a terminal acacH group and on the opposite side a paraffin chain of various lengths. By changing the length of these flexible chains (n=4, 8, 12) and the nature of the counter‐anions (PF6−, BF4−, NTf2−), room‐temperature ionic liquids were produced. Their application for the extraction of lanthanide salts (Eu, Tb) from dilute aqueous solution has been investigated. The presence of a strong UV absorber (imidazolium ring, λabs=290 nm) allows photosensitisation of the EuIII and TbIII luminescence by efficient energy transfer, and thus extraction of these two lanthanides can be followed by fluorescence techniques. It appears that loading of the ionic liquids onto silica particles pre‐treated with a dilute aqueous solution of NaOH is the most efficient way to obtain fast and almost quantitative (>99.9 %) extraction of the metal ions as their diketonato complexes. The procedure is reproducible and the loaded SiO2 particles can be simply treated with acid to strip the metal ions and regenerate the adsorbed (protonated) extractant.
Samarium Diiodide Induced Cyclizations of γ‐, δ‐ and ε‐Indolyl Ketones: Reductive Coupling, Intermolecular Trapping, and Subsequent Transformations of Indolines
Authors: Beemelmanns Christine , Lentz Dieter , Reissig Hans‐Ulrich 
Published: July 2011

AbstractThis comprehensive study describes our results of samarium diiodide induced 5‐exo‐trig to 8‐exo‐trig cyclization/alkylation sequences of 3′‐acceptor‐substituted indolyl ketones. All cyclization precursors were easily prepared by simple N‐alkylation or N‐acylation of indole derivatives with the corresponding iodo alkanones, acid chlorides, or lactones. After treatment of indolyl ketones with two equivalents of SmI2, the generated stabilized carbanionic intermediates were trapped with different electrophiles leading to a variety of highly substituted indoline derivatives in good to very good yields. In general, the cyclization products were obtained as single diastereomers bearing a newly generated quaternary center, a common structural motif in various indole alkaloids. The relative configurations of the products were established by NOE experiments and by single‐crystal analysis and follow the rules already established. Furthermore, the obtained products were subjected to a series of chemical transformations, such as oxidation, reduction, and metathesis reactions resulting in a range of interesting synthetic building blocks valuable for further applications.
Nickel‐Catalyzed CH Arylation of Azoles with Haloarenes: Scope, Mechanism, and Applications to the Synthesis of Bioactive Molecules
Authors: Yamamoto Takuya , Muto Kei , Komiyama Masato , Canivet Jérôme , Yamaguchi Junichiro , Itami Kenichiro 
Published: July 2011

AbstractNovel nickel‐based catalytic systems for the CH arylation of azoles with haloarenes and aryl triflates have been developed. We have established that Ni(OAc)2/bipy/LiOtBu serves as a general catalytic system for the coupling with aryl bromides and iodides as aryl electrophiles. For couplings with more challenging electrophiles, such as aryl chlorides and triflates, the Ni(OAc)2/dppf (dppf=1,1′‐bis(diphenylphosphino)ferrocene) system was found to be effective. Thiazoles, benzothiazoles, oxazoles, benzoxazoles, and benzimidazoles can be used as the heteroarene coupling partner. Upon further investigation, we discovered a new protocol for the present coupling using Mg(OtBu)2 as a milder and less expensive alternative to LiOtBu. Attempts to reveal the mechanism of this nickel‐catalyzed heterobiaryl coupling are also described. This newly developed methodology has been successfully applied to the syntheses of febuxostat (a xanthine oxidase inhibitor that is effective for the treatment of gout and hyperuricemia), tafamidis (effective for the treatment of TTR amyloid polyneuropathy), and texaline (a natural product having antitubercular activity).
Modeling of the Laminar Flow in the Entrance Region of Tubes and Ducts and its Impact on the Residence Time Distribution
Authors: Ham Jong‐Ho , Lohse Rolf , Platzer Bernd 
Published: July 2011

AbstractFür die Geschwindigkeitsverteilung im Einlaufbereich von laminar durchströmten Rohren und Kanälen werden ein 1‐Bereichs‐ und ein 2‐Bereichs‐Modell vorgestellt. Diese ermöglichen die Berechnung der Verweilzeitverteilung unter dem Einfluss der Einlaufeffekte. Für den dispersionsfreien Fall kann eine analytische Lösung angegeben werden. Für die Betrachtung von Fällen mit Dispersion wird auf das Zellenmodell mit Platzwechselwahrscheinlichkeit (ZEMP) zurückgegriffen, dessen numerische Ergebnisse mit den schon früher vorgestellten halbempirischen Ansätzen für die Verweilzeitverteilung mit einer Gleichung verdichtet werden können. Diese Vorgehensweise ermöglicht die schnelle Quantifizierung der Auswirkungen verschiedener Einflussparameter auf die Verweilzeitverteilung von relativ kurzen Rohren und Kanälen.
Micellar Solutions and Microemulsions as Media for Catalytic Reactions
Authors: Schomäcker Reinhard , Schwarze Michael , Nowothnick Henriette , Rost Anke , Hamerla Tobias 
Published: July 2011

AbstractIn dieser Übersicht wird ein Konzept für die reaktionstechnische Nutzung von wässrigen Tensidlösungen und Wasser/Tensid/Lösungsmittel‐Gemischen als Reaktionsmedien für katalytische Reaktionen vorgestellt. Dabei werden drei Beispiele beschrieben, für die ein Reaktionsmedium formuliert werden konnte, das sowohl optimale Bedingungen für den Ablauf der Reaktionen bietet als auch eine effiziente Rückgewinnung des Katalysators ermöglicht.
Ferromagnetism Exhibited by Nanoparticles of Noble Metals
Authors: Maitra Urmimala , Das Barun , Kumar Nitesh , Sundaresan Athinarayanan , Rao C. N. R. 
Published: July 2011

AbstractGold nanoparticles with average diameters in the range 2.5–15 nm, prepared at the organic/aqueous interface by using tetrakis(hydroxymethyl)phosphonium chloride (THPC) as reducing agent, exhibit ferromagnetism whereby the saturation magnetization MS increases with decreasing diameter and varies linearly with the fraction of surface atoms. The value of MS is higher when the particles are present as a film instead of as a sol. Capping with strongly interacting ligands such as alkane thiols results in a higher MS value, which varies with the strength of the metal–sulfur bond. Ferromagnetism is also found in Pt and Ag nanoparticles prepared as sols, and the MS values vary as Pt>Au>Ag. A careful study of the temperature variation of the magnetization of Au nanoparticles, along with certain other observations, suggests that small bare nanoparticles of noble metals could indeed possess ferromagnetism, albeit weak, which is accentuated in the presence of capping agents, specially alkane thiols which form strong metal–sulfur bonds.
Nanoscale Effects on Thermodynamics and Phase Equilibria in Oxide Systems
Authors: Navrotsky Alexandra 
Published: July 2011

AbstractBecause different solid materials (phases) have different surface energies, equilibria among them will be significantly affected by particle size. This Minireview summarizes experimental (calorimetric) data for the surface energies of oxides and discusses shifts in the stability of polymorphs, the thermodynamics of hydration, and oxidation–reduction reactions in nanoscale oxide systems.
Confocal backscattering spectroscopy for leukemic and normal blood cell discrimination
Authors: Greiner Cherry , Hunter Martin , Huang Peter , Rius Francisca , Georgakoudi Irene 
Published: July 2011

AbstractLeukemia is the most common pediatric cancer and leading cause of cancer related deaths in children. Improvements in the assessment of leukemic cells have the potential to influence not only the diagnosis of leukemia, but also the risk assessment of patients during the course of the treatment, both of which are important for improving the cure rate for this disease. In this study, we report on the design and performance of a confocal laser based system built to collect backscattered light over a range of 26° at 405, 488, and 633 nm to discriminate leukemic cells from normal red blood cells (RBC) and white blood cells (WBC). The design of the system is based on the spectral differences observed from spectroscopy measurements with a similar system designed with a white light source. Significant differences are observed in the intensity and wavelength dependence of leukemic cells from normal RBC and WBC. Specifically, the distinct light scattering of RBC is due to hemoglobin absorption, allowing for its discrimination from leukemic cells, mononuclear, and polymorphonuclear WBC particularly at certain wavelengths. Meanwhile, the high scattering intensities of polymorphonuclear WBC reflect the intracellular complexity of these cells in comparison to the leukemic or normal lymphocytes. Additionally, the detected light scattering spectra for leukemic cells are consistently steeper in comparison to normal WBC, which we attributed to differences in the fractal organization of intracellular scatterers. Based on our findings, the system has potential applications in the detection and quantification of leukemic cells in blood either in vivo or in vitro, using microfluidic‐based systems, for disease monitoring. © 2011 International Society for Advancement of Cytometry
Duloxetine in the treatment of binge eating disorder with depressive disorders: A placebo‐controlled trial
Authors: Guerdjikova Anna I. , McElroy Susan L. , Winstanley Erin L. , Nelson Eric B. , Mori Nicole , McCoy Jessica , Keck Paul E. , Hudson James I. 
Published: July 2011

AbstractObjective:This study evaluated duloxetine in the treatment of binge eating disorder (BED) with comorbid current depressive disorders.Method:In this 12‐week, double‐blind, placebo‐controlled trial, 40 patients with Diagnostic and Statistical Manual of Mental Disorders‐IV‐TR BED and a comorbid current depressive disorder received duloxetine (N = 20) or placebo (N = 20). The primary outcome measure was weekly binge eating day frequency.Results:In the primary analysis, duloxetine (mean 78.7 mg/day) was superior to placebo in reducing weekly frequency of binge eating days (p = .04), binge eating episodes (p = .02), weight (p = .04), and Clinical Global Impression‐Severity of Illness ratings for binge eating (p = .02) and depressive disorders (p = .01). Changes in body mass index and measures of eating pathology, depression, and anxiety did not differ between the two groups.Discussion:Duloxetine may be effective for reducing binge eating, weight, and global severity of illness in BED with a comorbid current depressive disorder, but this finding needs confirmation in larger, placebo‐controlled trials. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012)