bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic Propargylic Substitution Reactions
Authors: Miyake Yoshihiro , Uemura Sakae , Nishibayashi Yoshiaki 
Published: October 2009

AbstractIn sharp contrast to the well‐established transition metal‐ catalyzed allylic substitution reactions, the study of the corresponding propargylic substitution reactions has been quite limited for constructing carbon–carbon and carbon–heteroatom bonds at the propargylic position. However, during the last decade, general and useful catalytic reactions have been developed extensively. In this Review, we summarize recent advances in catalytic propargylic substitution reactions of propargylic alcohols and their derivatives with heteroatom‐ and carbon‐centered nucleophiles. In addition to a variety of transition metals, such as Ru, Re, Rh, Ir, Ni, Pd, Pt, and Cu, which form organometallic species as intermediates, several Lewis acids and Brønsted acids are also applicable as catalysts in these reactions. The reaction mechanism and the scope of nucleophiles that can be used depend on the nature of the catalysts. Some examples of enantioselective substitution reactions at the propargylic position are also described.
Photocontrolled Ring‐Opening Polymerization of Strained Dicarba[2]Ferrocenophanes: A Route to Well‐Defined Polyferrocenylethylene Homopolymers and Block Copolymers
Authors: Herbert David E. , Mayer Ulrich F. J. , Gilroy Joe B. , López‐Gómez María J. , Lough Alan J. , Charmant Jonathan P. H. , Manners Ian 
Published: October 2009

AbstractThe ring‐opening polymerization (ROP) behavior of a variety of substituted 1,1′‐ethylenylferrocenes, or dicarba[2]ferrocenophanes, is reported. The electronic absorption spectra and tilted solid‐state structures of the monomers rac‐[Fe(η5‐C5H4)2(CHiPr)2] (7), [Fe(η5‐C5H4)2(C(H)MeCH2)] (8), and rac‐[Fe(η5‐C5H4)2(CHPh)2] (9) are consistent with the presence of substantial ring strain, which was exploited to synthesize soluble, well‐defined polyferrocenylethylenes (PFEs) [Fe(η5‐C5H4)2(C(H)MeCH2)]n (12) and [Fe(η5‐C5H4)2(CHPh)2]n (13) through photocontrolled ROP. Polymer chain lengths could be controlled by the monomer‐to‐initiator ratio up to about 50 repeat units and, consistent with the “living” nature of the polymerizations, sequential block copolymerization with a sila[1]ferrocenophane led to polyferrocenylethylene–polyferrocenylsilane (PFE‐b‐PFS) block copolymers (14 and 15). PFE polymers 12 and 13 showed two reversible oxidation waves, indicative of appreciable Fe⋅⋅⋅Fe interactions along the polymer backbone. The diblock copolymers were characterized by NMR spectroscopy, GPC analysis, and cyclic voltammetry.
Chiral Encapsulation by Directional Interactions
Authors: Szumna Agnieszka 
Published: October 2009

AbstractThe complexation of chiral guests in the cavity of dimeric self‐assembled chiral capsule 12 was studied by using NMR spectroscopy and X‐ray crystallography. Capsule 12 has walls composed of amino acid backbones forming numerous directional binding sites that are arranged in a chiral manner. The polar character of the interior dictates the encapsulation preferences towards hydrophilic guests and the ability of the capsule to extract guests from water into an organic phase. Chiral discrimination towards hydroxy acids was evaluated by using association constants and competition experiments, and moderate de values were observed (up to 59 %). Complexes with one or two guest molecules in the cavity were formed. For 1:1 complexes, solvent molecules are coencapsulated; this influences guest dynamics and makes the chiral recognition solvent dependent. Reversal of the preferences can be induced by coencapsulation of a nonchiral solvent in the chiral internal environment. For complexes with two guests, filling of the capsule’s internal space can be very effective and packing coefficients of up to 70 % can be reached. The X‐ray crystal structure of complex 12⊃((S)‐6)2 with well‐resolved guest molecules reveals a recognition motif that is based on an extensive system of hydrogen bonds. The optimal arrangement of interactions with the alternating positively and negatively charged groups of the capsule’s walls is fulfilled by the guest carboxylic groups acting simultaneously as hydrogen‐bond donors and acceptors. An additional guest molecule interacting externally with the capsule reveals a possible entrance mechanism involving a polar gate. In solution, the structural features and dynamic behavior of the D4‐symmetric homochiral capsule were analyzed by variable‐temperature NMR spectroscopy and the results were compared with those for the S8‐symmetric heterochiral capsule.
Spectroscopic and Mechanistic Studies on Oxidation Reactions Catalyzed by the Functional Model SR Complex for Cytochrome P450: Influence of Oxidant, Substrate, and Solvent
Authors: Hessenauer‐Ilicheva Natalya , Franke Alicja , Wolak Maria , Higuchi Tsunehiko , van Eldik Rudi 
Published: October 2009

AbstractKinetic and mechanistic studies on the formation of an oxoiron(IV) porphyrin cation radical bearing a thiolate group as proximal ligand are reported. The SR complex, a functional enzyme mimic of P450, was oxidized in peroxo‐shunt reactions under different experimental conditions with variation of solvent, temperature, and identity and excess of oxidant in the presence of different organic substrates. Through the application of a low‐temperature rapid‐scan stopped‐flow technique, the reactive intermediates in the SR catalytic cycle, such as the initially formed SR acylperoxoiron(III) complex and the SR high‐valent iron(IV) porphyrin cation radical complex [(SR.+)FeIVO], were successfully identified and kinetically characterized. The oxidation of the SR complex under catalytic conditions provided direct spectroscopic information on the reactivity of [(SR.+)FeIVO] towards the oxidation of selected organic substrates. Because the catalytically active species is a synthetic oxoiron(IV) porphyrin cation radical bearing a thiolate proximal group, the effect of the strong electron donor ligand on the formation and reactivity/stability of the SR high‐valent iron species is addressed and discussed in the light of the reactivity pattern observed in substrate oxygenation reactions catalyzed by native P450 enzyme systems.
Synthesis of Multiantennary Complex Type N‐Glycans by Use of Modular Building Blocks
Authors: Unverzagt Carlo , Gundel Gislinde , Eller Steffen , Schuberth Ralf , Seifert Joachim , Weiss Harald , Niemietz Mathäus , Pischl Matthias , Raps Claudia 
Published: October 2009

AbstractA modular set of oligosaccharide building blocks was developed for the synthesis of multiantennary N‐glycans of the complex type, which are commonly found on glycoproteins. The donor building blocks were laid out for the elongation of a core trisaccharide acceptor (β‐mannosyl chitobiose) conveniently protected with a single benzylidene moiety at the β‐mannoside. Through two consecutive regio‐ and stereoselective couplings the donors gave N‐glycans with three to five antennae in high yields. Due to the consistent protection group pattern of the donors the deprotection of the final products can be performed by using a general reaction sequence.
Facile Purification of Porous Metal Terephthalates with Ultrasonic Treatment in the Presence of Amides
Authors: Haque Enamul , Khan Nazmul Abedin , Lee Ji Eun , Jhung Sung Hwa 
Published: October 2009

AbstractA facile purification method for metal–organic frameworks (MOFs), especially the ones containing insoluble 1,4‐benzenedicarboxylic acid (terephthalic acid) in the pore, has been suggested. The purification method consists of the treatment of the MOF with amides such as N,N‐dimethylformamide, especially under ultrasound treatment. The purification is completed within 1 h at 70 °C as has been confirmed by XRD, nitrogen adsorption, FTIR and TGA measurements. The purification method proved to be simple, one‐step, fast and energy‐efficient. The MOFs purified by the proposed method show high surface area and micropore volume, confirming the efficiency of the method. The proposed method will lead to a new access to activate (for example, to remove carboxylic acids) MOFs that are unstable above around 100 °C. Additionally, the method may be used to transform a non‐porous MOF‐type material into a porous MOF structure. However, adequate solvents will be necessary for the facile purification of MOFs.
On minimum Hellinger distance estimation
Authors: Wu Jingjing , Karunamuni Rohana J. 
Published: October 2009

AbstractEfficiency and robustness are two fundamental concepts in parametric estimation problems. It was long thought that there was an inherent contradiction between the aims of achieving robustness and efficiency; that is, a robust estimator could not be efficient and vice versa. It is now known that the minimum Hellinger distance approached introduced by Beran [R. Beran,Annals of Statistics1977;5:445–463] is one way of reconciling the conflicting concepts of efficiency and robustness. For parametric models, it has been shown that minimum Hellinger estimators achieve efficiency at the model density and simultaneously have excellent robustness properties. In this article, we examine the application of this approach in two semiparametric models. In particular, we consider a two‐component mixture model and a two‐sample semiparametric model. In each case, we investigate minimum Hellinger distance estimators of finite‐dimensional Euclidean parameters of particular interest and study their basic asymptotic properties. Small sample properties of the proposed estimators are examined using a Monte Carlo study. The results can be extended to semiparametric models of general form as well. The Canadian Journal of Statistics 37: 514–533; 2009 © 2009 Statistical Society of Canada
Virtual Screening against p50 NF‐κB Transcription Factor for the Identification of Inhibitors of the NF‐κB–DNA Interaction and Expression of NF‐κB Upregulated Genes
Authors: Piccagli Laura , Fabbri Enrica , Borgatti Monica , Bianchi Nicoletta , Bezzerri Valentino , Mancini Irene , Nicolis Elena , Dechecchi Cristina M. , Lampronti Ilaria , Cabrini Giulio , Gambari Roberto 
Published: October 2009

AbstractVirtual screening against NF‐κB p50 using docking simulations was applied by starting from a three‐dimensional (3D) database containing more than 4.6 million commercially available structures. This database was filtered by specifying a subset of commercially available compounds sharing a (2E,Z)‐3‐(2‐hydroxyphenyl)‐2‐propenoate substructure and relevant druglike properties. Docking to p50 NF‐κB was performed with a test set of six known inhibitors of NF‐κB–DNA interactions. In agreement with docking results, the highest‐scored compound displayed a high level of inhibitory activity in electrophoretic mobility shift assay (EMSA) experiments (inhibition of NF‐κB–DNA interactions) and on biological functions dependent on NF‐κB activity (inhibition of IL‐8 gene expression in cystic fibrosis IB3‐1 cells). We found that this in silico screening approach is suitable for the identification of low‐molecular‐weight compounds that inhibit NF‐κB–DNA interactions and NF‐κB‐dependent functions. Information deduced from the discovery of the new lead compound and its binding mode could result in further lead optimization resulting in more potent NF‐κB inhibitors.
Leukocytosis at diagnosis and the risk of subsequent thrombosis in patients with low‐risk essential thrombocythemia and polycythemia vera
Authors: Gangat Naseema , Wolanskyj Alexandra P. , Schwager Susan M. , Hanson Curtis A. , Tefferi Ayalew 
Published: October 2009

AbstractBACKGROUND:Advanced age and a history of thrombosis were well‐established risk factors for thrombosis in essential thrombocythemia (ET) and polycythemia vera (PV); cytoreductive therapy was indicated in their presence. Recent studies have suggested leukocytosis as an additional risk factor; however, such an association would be treatment‐relevant in the context of low‐risk disease.METHODS:In this retrospective study, a Cox proportional hazards model was used to determine the impact of various clinical and laboratory variables, including leukocytosis, on thrombosis‐free survival (TFS). Arterial‐specific or venous‐specific TFS curves for different leukocyte count‐defined risk groups were constructed by the Kaplan‐Meier method and compared using the log‐rank test.RESULTS:A total of 407 low‐risk patients (254 with ET and 153 with PV) were considered. After a respective median follow‐up of 104 months and 130 months, respectively, 47 (19%) patients with ET and 41 (27%) with PV experienced a total of 55 (41 arterial and 14 venous) and 46 (22 arterial and 24 venous) thrombotic events, respectively. Leukocytosis at the time of diagnosis, defined by a cutoff level of either 15 or 9.4 × 109/L, did not appear to be predictive of either arterial or venous thrombosis during follow‐up; similar results were obtained when analysis was restricted to patients with platelet counts of <1000 × 109/L. Instead, advanced age was found to be significantly associated with arterial thrombosis in patients with PV and higher hemoglobin level with venous thrombosis in patients with ET.CONCLUSIONS:In the current retrospective study, leukocytosis at diagnosis did not appear to influence the risk of thrombosis in either ET or PV. However, a prospective study is required before leukocytosis is taken into account during treatment decisions in these disorders. Cancer 2009. © 2009 American Cancer Society.
Clinical utility of postchemoradiation endoscopic brush cytology and biopsy in predicting residual esophageal adenocarcinoma
Authors: Peng Hong‐Qi , Halsey Kevin , Sun Chen‐Chih J. , Manucha Varsha , Nugent Summer , Rodgers William H. , Suntharalingam Mohan , Greenwald Bruce D. 
Published: October 2009

AbstractBACKGROUND:Esophageal adenocarcinoma generally carries a poor prognosis. Treatment with combination chemoradiation (CRT) followed by esophagectomy is becoming common. A pathologic complete response is uncommon but predicts improved survival. Identifying the subset of patients with residual carcinoma has potential management implications. Post‐CRT endoscopic brush cytology and biopsy may detect residual tumor; however, the accuracy and clinical value of these methods remain unclear.METHODS:Sixty‐seven patients with esophageal adenocarcinoma who underwent preoperative CRT and post‐CRT endoscopic brush cytology and biopsy followed by esophagectomy were identified. By using esophagectomy histology as the gold standard, the performance of cytology and biopsy was evaluated in diagnosing residual carcinoma. Two pathologists independently reviewed all false‐negative and false‐positive cases and resolved disagreements by consensus.RESULTS:The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of cytology for diagnosing residual carcinoma were 26%, 95%, 92%, 35%, and 45%, respectively. For biopsy, these rates were 13%, 90%, 75%, 31%, and 36%, respectively. Sampling error accounted for false‐negative diagnoses in approximately 66% of cytology analyses and 98% of biopsy analyses. Approximately 33% of false‐negative cytology analyses and 1 false‐negative biopsy analysis were caused by the under–recognition of tumor cells. Major diagnostic pitfalls included obscuring acute inflammation, necrosis, tumor cells that mimicked benign cells with radiation/reactive atypia, and the under recognition of mucin‐containing adenocarcinoma cells.CONCLUSIONS:Brush cytology and biopsy were specific but not sensitive methods for predicting residual cancer after CRT. However, cytology was superior. The current results indicated that brush cytology can be used alone to diagnose residual esophageal carcinoma, and awareness of specific diagnostic pitfalls will help pathologists improve its accuracy. Cancer (Cancer Cytopathol) 2009. © 2009 American Cancer Society.
Cancer size, histotype, and cellular grade may limit the success of fine‐needle aspiration cytology for screen‐detected breast carcinoma
Authors: Manfrin Erminia , Falsirollo Francesca , Remo Andrea , Reghellin Daniela , Mariotto Renata , Dalfior Daniela , Piazzola Elena , Bonetti Franco 
Published: October 2009

AbstractBACKGROUND:Fine‐needle aspiration cytology (FNAC) was adopted as the first‐line method to assess breast lesions in the Verona Breast Cancer Screening Program. The radiological and pathological factors relating to the success of FNAC in breast cancer series were evaluated.METHODS:Between July 1999 and June 2004, 418 breast cancers were submitted to FNAC in the Verona Breast Cancer Screening Program. The results of FNAC diagnoses were compared with final histology. The FNAC sensitivity rate, underestimation of malignancy rate, and inadequacy rate were correlated with histotype, size, grading, and radiologic imaging.RESULTS:Of the 418 cancers, 95 were in situ, and 323 were invasive. The sensitivity rate was higher in invasive cancers (P < .001), and the underestimation of malignancy rate was greater in in situ cancers (P = .002). Lobular type cancers had a lower sensitivity rate in invasive and in situ cancers. The sensitivity rate was 100% in medullary, mucinous, and papillary cancers, and no case had inadequate sampling. The underestimation of malignancy rate was higher in tubular carcinoma (18.2%); lobular carcinoma showed a higher inadequacy rate (10.4%). The sensitivity rate was lower and the underestimation of malignancy rate was higher in low‐grade carcinomas and in lesions <1 cm (P < .001). The performance of FNAC was not significantly influenced by mammographic imaging of lesions.CONCLUSIONS:Low‐grade cancer histotype, cancer size <1 cm, and lobular and tubular histotypes limit the possibility of obtaining positive results by FNAC. Operator experience and multidisciplinary consultation may help in overcoming these limitations. Pathologists must be aware of the limits of FNAC; results must be critically evaluated in light of the triple assessment. Cancer (Cancer Cytopathol) 2009. © 2009 American Cancer Society.
Rotating elastic bodies in Einstein gravity
Authors: Andersson Lars , Schmidt Bernd G. , Beig Robert 
Published: October 2009

AbstractWe prove that, given a stress‐free, axially symmetric elastic body, there exists, for sufficiently small values of the gravitational constant and of the angular frequency, a unique stationary, axisymmetric solution to the Einstein equations coupled to the equations of relativistic elasticity with the body performing rigid rotations around the symmetry axis at the given angular frequency. © 2009 Wiley Periodicals, Inc.
An Open Source performance tools software suite for scientific computing
Authors: Mucci Philip J. , Mohan Tushar 
Published: October 2009

AbstractWith the rapid replacement of closed, homogeneous, proprietary HPC systems by heterogeneous, Linux‐MPI cluster systems, the state of performance monitoring and analysis tools has become a cause for concern. Proprietary systems, despite their drawbacks, provided consistent tools of high quality. Modern Linux cluster systems, on the other hand, benefit from a wide variety of Open Source tools in differing stages of evolution. Recognizing that Linux clusters are here to stay, SiCortex has taken a unique approach of integrating and enhancing Open Source tools into a production‐quality suite. Further, as a tribute to the unrewarded Open Source community developers and for more pragmatic reasons, such as long‐term sustainability, changes made to the tools are fed upstream to the original tool developers. In this paper, we present an overview of the SiCortex tools' suite, and some of the challenges and successes we had in the process of realizing it. Copyright © 2009 John Wiley & Sons, Ltd.
Intrinsic Neutral and Anionic Structures of Glutathione
Authors: Ko Yeon Jae , Wang Haopeng , Li Xiang , Bowen Kit. H. , Lecomte Frédéric , Desfrançois Charles , Poully Jean‐Christophe , Grégoire Gilles , Schermann Jean Pierre 
Published: October 2009

AbstractGas‐phase intrinsic structures of intact neutral and anionic glutathione (GSH) have been determined by means of a combination of negative ion photo‐electron spectroscopy and quantum chemistry calculations. The inferred structures of the neutral parents of those peptide anions are canonical (non‐zwitterionic). These intrinsic structures are compared to those already known in aqueous solution or determined by crystallography in binding sites of enzymes.
Child‐inclusive mediation in cases of domestic violence in Australia
Authors: Hart Amanda Shea 
Published: October 2009

AbstractDomestic violence is a common driver of family dissolution. Cases involving domestic violence are core business in the Australian family law jurisdiction. Family mediation is growing as an alternative to litigation for separated families in dispute over parenting arrangements. The specialized intervention of child‐inclusive mediation is increasingly used to resolve family disputes in the best interests of the child. However, this child‐empowering practice is often avoided by mediators where domestic violence is an issue. This article identifies some complex factors that need to be addressed and researched for appropriate development and use of child‐inclusive mediation to enhance social justice for child subjects of parenting disputes from violent families.
Unofficial international conflict resolution: Is there a Track 1½? Are there best practices?
Authors: Nan Susan Allen , Druckman Daniel , Horr Jana El 
Published: October 2009

AbstractAnalysis of twenty‐four cases of unofficial international conflict resolution initiatives, done according to similarities across seven variables, shows that the practice of “Track 1½” diplomacy is distinct from Track 2 diplomacy. Furthermore, these initiatives are distinguished by their focus on process or diverse goals. Multidimensional scaling organized the cases into four groupings of similar initiatives: Track 1½ process‐focused, Track 1½ diversified, Track 2 process‐focused, and Track 2 diversified. The variety of approaches used in these twenty‐four cases of high‐quality international conflict resolution initiatives suggests best practices. These practices should be considered sensitive to context rather than a standard set of procedures used regardless of conflict environment.
Practice note: Challenging conventions in challenging conditions: Thirty‐minute mediations at Burning Man
Authors: Hedeen Timothy , Kelly Ron 
Published: October 2009

AbstractFor the past eight years, Ron Kelly has offered mediation services at the annual Burning Man festival. The process he designed appears to bring significant help to disputing couples in half an hour, and useful conflict coaching to individuals in fifteen minutes. It is tightly formatted—and uses a kitchen timer. This interview covers the origins of his process and explores how the creativity and generosity of the festival are available to all mediators.
Patterns of Wnt pathway activity in the mouse incisor indicate absence of Wnt/β‐catenin signaling in the epithelial stem cells
Authors: Suomalainen Marika , Thesleff Irma 
Published: October 2009

AbstractThe Wnt pathway is crucial for tooth development as shown by dental defects caused by impaired Wnt signaling in mouse and human. We investigated Wnt signaling in continuously growing mouse incisors focusing on epithelial stem cells. TenWntligands were expressed both in the dental epithelium and mesenchyme, and were associated mainly with odontoblast and ameloblast differentiation. Wnt/β‐catenin activity was detected in mesenchyme inBATgalandTOPgalreporter mice whileAxin2, also a reporter of Wnt/β‐catenin signaling, was expressed additionally in the epithelium.Axin2was, however, excluded from the epithelial stem cells in the cervical loop. Interestingly, these cells expressed specificallyLgr5, a Wnt target gene and stem cell marker in the intestine, suggesting thatLgr5is a marker of incisor stem cells but is not regulated by Wnt signaling in the incisor. We conclude that epithelial stem cells in the mouse incisors are not regulated directly by Wnt/β‐catenin signaling. Developmental Dynamics 239:364–372, 2010. © 2009 Wiley‐Liss, Inc.