bluuebunny/crossref_metadata_2025_split huggingface dataset:
Upgrading the adhesion properties of a fast‐curing epoxy using hydrophilic/hydrophobic hyperbranched poly(amidoamine)s
Authors: Essawy Hisham A. , Mohamed Heba A. , Elsayed Nadia H. 
Published: June 2012

AbstractA homologous series of hyperbranched polymers (HBPs) was prepared following a well‐defined method and their formation in a polymeric form bearing different extents of branching with amine functional groups at the terminals was verified using different techniques such as Fourier Transform Infrared, 1H Nuclear Magnetic Resonance, Differential Scanning Calorimetry, and Gel Permeation Chromatography. Toughening of a commercially available fast cure epoxy was aimed through reactive blending with the formed HBPs that exhibit variation in polarity and branching according to the relevant synthesis strategy employed for each polymer. The mechanical properties (impact resistance, pull‐off adhesion, and bending) of the resulting coating films pertaining to each epoxy formulation after adhering to metal substrates revealed obvious progress in their performance with respect to a control sample that was hardened exclusively in absence of any HBP. The results were explained on the light of the ability of this class of materials to impose flexibility and dilute the intensive crosslink density associated frequently with the rapid curing of epoxy systems. The extent of gained enhancement for each formulation was accounted for by the molecular architecture of the HBPs, their degrees of branching, polarity, and relative reactive contents of primary amino groups in each case. In addition, the influence of these parameters on a proper wetting over the substrate and morphology of the films in each case was also studied using scanning electron microscopy. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Modified poly(vinylidene fluoride) hollow fiber composite membranes reinforced by hydroxyapatite nanocrystal whiskers
Authors: Lang Wan‐Zhong , Ji Qin , Shen Jian‐Ping , Guo Ya‐Jun , Chu Lian‐Feng 
Published: June 2012

AbstractThe modified poly(vinylidene fluoride) (PVDF) hollow fiber composite membranes reinforced by hydroxyapatite (HAP) nanocrystal whiskers were fabricated with wet‐spinning method. The PVDF/HAP/N‐methyl‐2‐pyrrolidone dope solutions experienced delayed demixing mechanism, and the precipitation rate slightly increased as the HAP whisker content increased. The cross sections of PVDF‐HAP and neat PVDF hollow fiber composite membranes were composed of five distinct layers: two skin layers, two finger‐like sublayers, and a sponge‐like layer. The Young's modulus of and tensile strength of the PVDF‐HAP hollow fiber membranes gradually increased with the addition of nano‐HAP whiskers. The elongation ratio was also improved, which was different from the polymeric membranes modified by other inorganic nanofillers. The permeation flux of the PVDF‐HAP hollow fiber membranes slightly increased with the increase of HAP content in the composite membranes as its hydrophilicity was improved. The crystallization behaviors of PVDF in the composite membranes were also investigated. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and characterization of porous chitosan–tripolyphosphate beads for copper(II) ion adsorption
Authors: Wu Shao‐Jung , Liou Tzong‐Horng , Yeh Chao‐Hsien , Mi Fwu‐Long , Lin Tsung‐Kuan 
Published: June 2012

AbstractPorous chitosan–tripolyphosphate beads, prepared by the ionotropic crosslinking and freeze‐drying, were used for the adsorption of Cu(II) ion from aqueous solution. Batch studies, investigating bead adsorption capacity and adsorption isotherm for the Cu(II) ion, indicated that the Cu(II) ion adsorption equilibrium correlated well with Langmuir isotherm model. The maximum capacity for the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, deduced from the use of the Langmuir isotherm equation, was 208.3 mg/g. The kinetics data were analyzed by pseudo‐first, pseudo‐second order kinetic, and intraparticle diffusion models. The experimental data fitted the pseudo‐second order kinetic model well, indicating that chemical sorption is the rate‐limiting step. The negative Gibbs free energy of adsorption indicated a spontaneous adsorption, while the positive enthalpy change indicated an endothermic adsorption process. This study explored the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, and used SEM/EDS, TGA, and XRD to examine the properties of adsorbent. The use of porous chitosan–tripolyphosphate beads to adsorb Cu(II) ion produced better and faster results than were obtained for nonporous chitosan–tripolyphosphate beads. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and Anticonvulsant Properties of New Mannich Bases Derived from 3,3‐Disubstituted Pyrrolidine‐2,5‐diones. Part IV
Authors: Obniska Jolanta , Chlebek Iwona , Kamiński Krzysztof 
Published: June 2012

AbstractA library of 21 new N‐Mannich bases of 3,3‐diphenyl‐ (5a–g), 3‐methyl‐3‐phenyl‐ (6a–g), and 3‐ethyl‐3‐methylpyrrolidine‐2,5‐diones (7a–g) were synthesized and evaluated for their anticonvulsant activity in the maximum electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure tests after intraperitoneal injection into mice. The acute neurological toxicity was determined applying the rotarod screen. The results in mice showed that 13 compounds were effective in the MES or/and scPTZ screen. From these, seven molecules were tested in the MES seizures after oral administration in rats. The quantitative studies showed that N‐[{4‐(2‐hydroxyethyl)‐piperazin‐1‐yl}‐methyl]‐3‐methyl‐3‐phenylpyrrolidine‐2,5‐dione (6c) and N‐[(4‐benzylpiperidin‐1‐yl)‐methyl]‐3‐methyl‐3‐phenylpyrrolidine‐2,5‐dione (6f) revealed higher protection in the MES and scPTZ tests than valproic acid or ethosuximide which were used as reference antiepileptic drugs. Four compounds (5c, 6c, 6e, 6f) showed high effectiveness in the 6‐Hz psychomotor seizure model of partial and therapy resistant epilepsy.
Hierarchical Nitrogen‐Doped Flowerlike ZnO Nanostructure and Its Multifunctional Environmental Applications
Authors: Bai Hongwei , Liu Zhaoyang , Sun Darren Delai 
Published: June 2012

AbstractHierarchical nitrogen‐doped ZnO flowerlike nanostructures were synthesized on a large scale. These nanostructures were characterized by FESEM, HRTEM, XRD, FTIR, XPS, and TGA, and their suitability for multifunctional environmental applications was investigated. The experimental results demonstrated that the hierarchical N‐doped ZnO flowerlike nanostructure enhances the photodegradation of methyl blue (MB) and acid orange 7 (AO7) by presenting a large specific surface area and high light utilization rate, inhibits the growth of bacteria without light irradiation, and increases the permeate flux when used in a membrane filtration system. These advantages of the hierarchical N‐doped ZnO flowerlike nanostructure brings benefits to the environmental application fields.
Research on bodies of the executed in German anatomy: An accepted method that changed during the Third Reich. Study of anatomical journals from 1924 to 1951
Authors: Hildebrandt Sabine 
Published: June 2012

AbstractWhile it is known that bodies of the executed were used for anatomical research in Germany during the Third Reich, it is unclear whether this type of work was unique to the time period or more common in Germany than elsewhere. The dissected persons and the anatomists involved have not been fully investigated. This study of anatomical journals from 1924 to 1951 shows that 166 out of 7,438 [2.2%] German language articles mentioned the use of “material” from the bodies of executed persons. In comparison, only 2 out of 4,702 English language articles explicitly mentioned bodies of the executed. From 1924 to1932, 33 of a total of 3,734 [1%] German articles listed the use of the executed. From 1933 to 1938 the number rose to 46 out of 2,265 [2%], and increased again from 1939 to 1945 to 73 out of 984 [7%]. After the war 15 out of 455 [3%] still dealt with “material” from the executed. German anatomists' familiarity with the use of the executed as a standard for healthy tissues even before 1933 may have contributed to the ease with which they accepted the “opportunities” (large‐scale studies and research on women) presented to them by unlimited access to bodies of the executed provided by the abusive National Socialist (NS) legislation and continued using them for some years after the war. German postwar anatomy was built in part on the bodies of NS victims. Information given in some publications will help with further identification of these victims. Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.
Solid‐state Circular Dichroism and Hydrogen Bonding, Part 2: The Case of Hypothemycin Re‐investigated
Authors: Pescitelli Gennaro 
Published: June 2012

ABSTRACTThe impact of crystalline forces on the solid‐state circular dichroism (CD) spectrum of hypothemycin (1), a biologically active molecule extracted from natural sources, has been analyzed by means of time‐dependent density functional theory CD calculations. Input structures were extracted from the X‐ray geometry of 1 and consisted in the isolated molecule, its cluster with five water molecules, and 20 different dimers (plus water molecules) representative of all the closest neighbors found in the crystal. The effects of solid‐state intermolecular hydrogen bonds and through‐space exciton couplings in determining the solid‐state CD spectrum of hypothemycin were evaluated and compared. Chirality 24:718–724, 2012. © 2012 Wiley Periodicals, Inc.
Influence of KRAS mutation status in metachronous and synchronous metastatic colorectal adenocarcinoma
Authors: Rose Jeffrey S. , Serna Derek S. , Martin Ludmila Katherine , Li Xiaobai , Weatherby Lynn M. , Abdel‐Misih Sherif , Zhao Weiqiang , Bekaii‐Saab Tanios 
Published: June 2012

AbstractBACKGROUND:Mutations in the v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) are present in approximately 30% to 40% of colorectal adenocarcinomas. Wild‐type (WT) KRAS mutation status is predictive of tumor response with epidermal growth factor receptor‐directed therapies, but the results from studies evaluating the prognostic value of KRAS status in localized disease have been contradictory. The prognostic value of KRAS in metastatic disease, specifically according to whether patients have synchronous or metachronous disease at presentation, is less understood.METHODS:One‐hundred ten consecutive patients with metastatic colorectal adenocarcinoma underwent testing for KRAS exon 2 mutations by polymerase chain reaction amplification and direct nucleotide sequencing. The clinical characteristics, treatments, and outcomes of these patients were then analyzed retrospectively, stratified according to whether patients presented with synchronous or metachronous metastasis and according to KRAS mutation status (WT or mutated).RESULTS:For the entire cohort, the median overall survival from the date of diagnosis of metastatic disease was 34.3 months (95% confidence interval, 28.3‐49.4 months) for patients with WT KRAS (n = 70). The median overall survival for patients with mutated KRAS (n = 40) was 40.3 months (95% confidence interval, 27.9‐51.1 months; log‐rank P = .91). Kaplan‐Meier survival analysis indicated that 3‐year overall survival and 5‐year overall survival were not statistically different. Within the subgroups of patients with synchronous and metachronous metastatic disease, no significant differences were observed in median overall survival, 3‐year overall survival, or 5‐year overall survival between the WT KRAS and mutated KRAS groups.CONCLUSIONS:In this study, KRAS mutation status did not influence overall survival in either synchronous or metachronous metastatic colorectal adenocarcinoma and, as such, had no prognostic role in this disease setting. Cancer 2012. © 2012 American Cancer Society.
Intracytoplasmic detection of TCL1—but not ILT7—by flow cytometry is useful for blastic plasmacytoid dendritic cell leukemia diagnosis
Authors: Angelot‐Delettre Fanny , Biichle Sabeha , Ferrand Christophe , Seilles Estelle , Gaugler Béatrice , Harrivel Veronique , Rosenthal‐Allieri Maria Alessandra , Deconinck Eric , Saas Philippe , Garnache‐Ottou Francine 
Published: June 2012

AbstractDiagnosis of blastic plasmacytoid dendritic cell neoplasm (BPDCN) or plasmacytoid dendritic cell leukemia (pDCL) is mainly based on immunophenotypical characterization of leukemic cells in blood or bone marrow samples. We tested by flow cytometry intracellular expression of the proto‐oncogene T‐cell leukemia 1 (TCL1), as well as membrane and intracellular expression of immunoglobulin‐like transcript 7 (ILT7) in 21 pDCL samples and 61 non‐pDC acute leukemia samples [i.e., 14 B‐acute lymphoblastic leukemia (B‐ALL), 9 T‐ALL and 38 acute myeloid leukemia (AML)]. TCL1 is highly expressed in all pDCL samples while at a statistically lower level in all B‐ALL and 34% of AML. Statistical analysis shows that intensity of TCL1 expression is a good marker for differential diagnosis of pDCL versus other acute leukemia (area under the receiver‐operating characteristic curve, [AUC]: 0.96). By contrast, ILT7 positivity is limited to few pDCL samples and cannot be useful for diagnosis purpose. In conclusion, high intracellular intensity of TCL1 expression is currently the best marker for pDC lineage assignment by flow cytometry, which is particularly useful to distinguish pDCL from CD4+ CD56+/− undifferentiated or monoblastic acute leukemia. Thus, intracellular TCL1 detection should be included in acute leukemia diagnosis panels used in hematology laboratories. © 2012 International Society for Advancement of Cytometry
Regulation of early xenopus embryogenesis by smad ubiquitination regulatory factor 2
Authors: Das Shaonli , Chang Chenbei 
Published: June 2012

AbstractBackground: Smad ubiquitination regulatory factor (Smurf) 1 and 2 are E3 ubiquitin ligases originally identified as inhibitors of transforming growth factor beta signaling and are shown to modulate multiple cellular activities. The roles of Smurfs in vertebrate embryogenesis, however, are not completely understood. Results: Here we investigate the function of Smurf2 during early Xenopus development. We show that distinctly from Smurf1, overexpression of Smurf2 in presumptive mesoderm interfered with mesoderm induction and caused axial defects, whereas knockdown of Smurf2 with antisense morpholino oligonucleotides resulted in expansion of the mesoderm. These results imply that Smurf2 may modulate nodal‐mediated mesodermal induction. Consistently, ventral expression of Smurf2 induced a partial secondary axis with head structures. In the ectoderm, Smurf2 resembled Smurf1 in controlling neural and epidermal marker expression and influencing head formation. Smurf1, but not Smurf2, additionally affected neural tube closure. Interestingly, both Smurfs could enhance as well as repress neural crest markers, implying that they modulate their targets dynamically during neural plate border specification. Conclusion: Our data demonstrate that Smurf1 and Smurf2 have overlapping and distinct functionalities during early frog embryogenesis; collectively, they regulate ectodermal and mesodermal induction and patterning to ensure normal development of Xenopus embryos. Developmental Dynamics 241:1260–1273, 2012. © 2012 Wiley Periodicals, Inc.
Ammonothermal Synthesis of AlkaliN,N′‐Bis(aminocarbonyl)phosphorodiamidates M[PO2(NHCONH2)2] (M = Na, K, Rb)
Authors: Wirnhier Eva , Boller Ruth Deborah , Schnick Wolfgang 
Published: June 2012

AbstractCompounds M[PO2(NHCONH2)2] with M = Na, K, and Rb, which are the salts ofN,N′‐bis(aminocarbonyl)phosphorodiamidic acid, were synthesized by ammonolysis of the corresponding alkali biuretooxophosphates M[PO2(NH)3(CO)2] (M = Na, K, Rb) at 350 °C and 120–150 bar in an autoclave. The structures were solved by single‐crystal X‐ray diffraction and exhibit 3D frameworks in whichN,N′‐bis(aminocarbonyl)phosphorodiamidate ions connect the corresponding alkali ions. The thermal behavior was investigated by combined thermogravimetric (TG) and differential thermal analysis (DTA) as well as temperature‐dependent powder X‐ray diffraction to evaluate applicability of the alkaliN,N′‐bis(aminocarbonyl)phosphorodiamidates as precursors for the synthesis of CNP(O) networks. In this context, the concept of Le Chatelier's principle for the hindrance of premature decomposition by applying elevated pressure was examined.
Access to Side‐On Bonded Tungsten Phosphanylphosphinidene Complexes
Authors: Grubba Rafał , Baranowska Katarzyna , Chojnacki Jarosław , Pikies Jerzy 
Published: June 2012

AbstractMetathesis reactions between diimido complexes of tungsten(VI) [(ArN)2WCl2] (Ar = 2,6‐iPr2C6H3) and lithium derivatives of diphosphanes R2P–P(SiMe3)Li (R = tBu and iPr) yield two anionic diimido complexes of tungsten with side‐on bonded phosphanylphosphinidene ligands, [(ArN)2WCl(η2‐R2P–P)]–. Both complexes are structurally characterized. A possible reaction mechanism and the role of donor solvents are discussed on the basis of NMR spectroscopic results.
Design and Diastereoselective Synthesis of C‐2,C‐20‐Diaryl Steroidal Derivatives
Authors: Rey Jullien , O'Riordan Timothy J. C. , Hu Haipeng , Snyder James P. , White Andrew J. P. , Barrett Anthony G. M. 
Published: June 2012

AbstractA novel and efficient synthetic strategy to access unique C‐2 substituted steroid analogues 3 and 4 is described. The unusual C‐2 aryl ether analogues 3 were shown to act as virtual antagonists of LRH‐1 and were prepared as single diastereoisomers, employing a fifteen‐step sequence from pregnenolone (9). The key steps include the stereoconvergent nucleophilic displacement of an epimeric mixture of 3‐keto 2‐bromo steroids, chemoselective carbonylation of an enol triflate and conversion of a thiopyridyl ester into an aryl ketone. The related C‐2 benzyl analogues 4 were prepared in a similar manner.
The Synthesis and Characterization of a Pentafluorosulfanylated Peptide
Authors: Lim Dong Sung , Lin Jin‐Hong , Welch John T. 
Published: June 2012

AbstractThe design and synthesis of pentafluorosulfanyl‐containing heptad amino acid sequence was described. The three‐dimensional conformation of the peptide was investigated by using CYANA (combined assignment and dynamics algorithm for NMR applications) and the integrated autoassignment. This study shows that the one of the diastereomers assumed a very tight coiled conformation in [D6]DMSO where both pentafluorosulfanyl groups assumed a synclinal relationship. The propensity of the protected heptapeptide to form such a tight coil and of the pentafluorosulfanyl groups to align so uniformly is suggestive of the utility of pentafluorosulfanylated amino acids in promoting conformational control.
Asymmetric Friedel–Crafts Alkylation of Indoles with Nitrodienes and 2‐Propargyloxy‐β‐nitrostyrenes Catalyzed by Diphenylamine‐Linked Bis(oxazoline)–Zn­(OTf)2 Complexes
Authors: Peng Jiahuan , Du Da‐Ming 
Published: June 2012

AbstractThe catalytic asymmetric Friedel–Crafts reaction of indoles with nitrodienes and 2‐propargyloxy‐β‐nitrostyrenes was systematically investigated with diphenylamine‐linked bis(oxazoline)–Zn(OTf)2 complexes. Moderate to good enantioselectivities were obtained with both kinds of substrates (up to 89 % ee for nitrodienes and up to 93 % ee for β‐nitrostyrene derivatives). Further transformation of the corresponding Friedel–Crafts alkylation product of indole with 2‐propargyloxy‐β‐nitrostyrene was carried out to give the chiral isoxazolobenzoxepane derivative, which is of medicinal chemistry interest, with retained enantiomeric purity.
Recent Highlights in Ketenimine Chemistry
Authors: Alajarin Mateo , Marin‐Luna Marta , Vidal Angel 
Published: June 2012

AbstractSelected recent developments in the chemistry of ketenimines are presented, demonstrating that heterocumulenes of this class are versatile reactive intermediates in the synthesis of nitrogenated heterocycles. This microreview includes examples of intramolecular nucleophilic and radical additions, biradical cyclizations, 4π‐ and 6π‐electrocyclic ring closures, [2+2], [3+2] and [4+2] cycloadditions, ketenimine‐to‐nitrile rearrangements and 1,3‐X, 1,5‐X and 1,5‐H shifts.
Catalytic Asymmetric Addition of Alkyllithium Reagents to Aromatic Aldehydes
Authors: Fernández‐Mateos Emilio , Maciá Beatriz , Yus Miguel 
Published: June 2012

AbstractHerein, we report the first efficient catalytic system for the asymmetric alkylation of aldehydes with organolithium reagents in the presence of titanium(IV) isopropoxide. A variety of alkyllithium reagents can be added to aromatic aldehydes in good yields with high enantioselectivities in a simple one‐pot procedure under mild conditions.
Buchwald–Hartwig Amination of (Hetero)aryl Chlorides by Employing Mor‐DalPhos under Aqueous and Solvent‐Free Conditions
Authors: Tardiff Bennett J. , Stradiotto Mark 
Published: June 2012

AbstractWe report on the application of the [Pd(cinnamyl)Cl]2/Mor‐DalPhos catalyst system in the Buchwald–Hartwig amination of (hetero)aryl chlorides with primary or secondary amines conducted either under aqueous conditions without the use of co‐solvents and/or surfactants or under solvent‐free conditions (52 examples). We have established that reactions of this type can be conducted without the rigorous exclusion of air, and in the case of the solvent‐free reactions, we have demonstrated that appropriately selected liquid and solid reagents can be employed successfully.
Synthesis of N‐Methyl‐2‐indolyl‐ and N‐Methyl‐2‐benzo[b]furyl‐Substituted Sulfoximines by Pd/Cu Co‐Catalyzed Domino Cross‐Coupling/Cyclization Reactions
Authors: Schumacher Ricardo F. , Honraedt Aurélien , Bolm Carsten 
Published: June 2012

AbstractDomino cross‐coupling/cyclization reactions of N‐propargyl sulfoximines and 2‐iodophenols or 2‐iodoanilides are catalyzed by a cooperative palladium/copper system to provide benzo[b]furan and indole derivatives in good to excellent yields. The reactions occur under mild conditions and tolerate a wide variety of functional groups.
Interleukin genes and associations with colon and rectal cancer risk and overall survival
Authors: Bondurant Kristina L. , Lundgreen Abbie , Herrick Jennifer S. , Kadlubar Susan , Wolff Roger K. , Slattery Martha L. 
Published: June 2012

AbstractInterleukins are a group of cytokines that contribute to growth and differentiation, cell migration, and inflammatory and anti‐inflammatory responses by the immune system. In our study, we examined genetic variation in genes from various anti‐inflammatory and proinflammatory interleukins to determine association with colon and rectal cancer risk and overall survival. Data from two population‐based incident studies of colon cancer (1,555 cases and 1,956 controls) and rectal cancer (754 cases and 954 controls) were used. After controlling for multiple comparisons, single nucleotide polymorphisms (SNPs) from four genes, IL3, IL6R, IL8, IL15, were associated with increased colon cancer risk, and CXCR1 and CXCR2 were significantly associated with increased rectal cancer risk. Only SNPs from genes within the IL‐8 pathway (IL8, CXCR1 and CXCR2) showed a significant association with both colon and rectal cancer risk. Several SNPs interacted significantly with IL8 and IFNG SNPs and with aspirin/non‐steroidal anti‐inflammatory drug (NSAID), cigarette smoking, estrogen use and BMI. For both colon and rectal cancer, increasing numbers of risk alleles were associated with increased hazard of death from cancer; the estimated hazard of death for colon cancer for the highest category of risk alleles was 1.74 (95% confidence interval [CI] 1.18–2.56) and 1.96 (95% CI 1.28–2.99) for rectal cancer. These data suggest that interleukin genes play a role in risk and overall survival for colon and rectal cancer.