bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cobalt(I)‐Mediated Preparation of Polyborylated Cyclohexadienes: Scope, Limitations, and Mechanistic Insight
Authors: Geny Anaïs , Lebœuf David , Rouquié Gabriel , Vollhardt K. Peter C. , Malacria Max , Gandon Vincent , Aubert Corinne 
Published: May 2007

AbstractA series of 1,3‐ and 1,4‐diboryl‐1,3‐cyclohexadienes have been prepared by intermolecular CoCp‐mediated [2+2+2] cocyclizations of alkynylboronic pinacolate esters with alkenes, followed by oxidative demetallation with iron(III) chloride. The effect of substitution at the borylated alkyne on chemo‐ and regioselectivities has been studied, suggesting steric control. The proper choice of substituents allowed the preparation of 1,3‐diborylated cyclohexadienes in a highly selective manner. Alternatively, 1,4‐diborylated cyclohexadienes could be prepared from diborylated diynes. The scope of this reaction has been examined and found to include electron‐poor, electron‐rich, linear, and cyclic alkenes. The diborylated cyclohexadienes were submitted to single or double Suzuki–Miyaura cross‐coupling reactions with haloarenes to afford polyarylated systems. The mechanism of the title reaction, including the regioselectivity of the cycloaddition steps, has been analyzed by means of DFT computations.
Practical Tactics in Resolution of Racemates via Diastereomeric Salt Formation
Authors: He Xu‐Chang , Qi Chuang‐Yu 
Published: May 2007

AbstractA practical tactics in the classical resolutions was illustrated for affording the desired isomers in maximum yields. According to the practical tactics resolution of racemic ethyl nipecotate, Corey lactone and huperzine A intermediate was successfully practiced. The basis of this practicability is the well‐known Marckwald principle.
Low‐Temperature Heat Capacities and Thermodynamic Properties of Octahydrated Barium Dihydroxide, Ba(OH)2·8H2O(s)
Authors: Di You‐Ying , Tan Zhi‐Cheng , Sun Li‐Xian 
Published: May 2007

AbstractLow‐temperature heat capacities of octahydrated barium dihydroxide, Ba(OH)2·8H2O(s), were measured by a precision automated adiabatic calorimeter in the temperature range from T=78 to 370 K. An obvious endothermic process took place in the temperature range of 345–356 K. The peak in the heat capacity curve was correspondent to the sum of both the fusion and the first thermal decomposition or dehydration. The experimental molar heat capacities in the temperature ranges of 78–345 K and 356–369 K were fitted to two polynomials. The peak temperature, molar enthalpy and entropy of the phase change have been determined to be (355.007±0.076) K, (73.506±0.011) kJ·mol−1 and (207.140±0.074) J·K−1·mol−1, respectively, by three series of repeated heat capacity measurements in the temperature region of 298–370 K. The thermodynamic functions, (HT−H298.15 K) and (ST−S298.15 K), of the compound have been calculated by the numerical integral of the two heat‐capacity polynomials. In addition, DSC and TG‐DTG techniques were used for the further study of thermal behavior of the compound. The latent heat of the phase change became into a value larger than that of the normal compound because the melting process of the compound must be accompanied by the thermal decomposition or dehydration of 7H2O.
Chemical Composition of Hydrilla Verticillata (L. f.) Royle in Taihu Lake
Authors: Xiao Yu , Wang Yan‐Li , Gao Shi‐Xiang , Sun Cheng , Zhou Zhong‐Yuan 
Published: May 2007

AbstractHydrilla verticillata (Linn. f.) Royle is a submerged plant for phytoremediation on Taihu Lake, China. The planted submerged plant should be harvested in every autumn to reduce the nutrition burden of the lake. Five compounds were firstly isolated by column chromatography and purified from the extractions of Hydrilla verticillata (Linn. f.) Royle. 1‐(5′‐Hydroxy‐4′‐hydroxymethyl‐1′‐methyl‐1H‐pyrrol‐2′‐yl)‐henicosa‐2,12,15‐trien‐1‐one (2) and thymidine (3) were identified by EIMS, 1H NMR, 13C NMR and IR spectra. Crystal loliolide (1) and sulfur‐gamma (4) were identified by X‐ray diffraction. Octadecanedioic acid (5) was also elucidated. Among them, compound 2 is a new natural compound, loliolide (1) and thymidine (3) are known bioactive substances. The results provided basic research data for exploring their application as medical materials.
Methyl Iodide Accelerated Asymmetric Epoxidation of Alkenes Catalyzed by Chiral Salen‐Mn(III) Complexes with Tertiary Amine Units
Authors: Sun Yang , Tang Ning 
Published: May 2007

AbstractA series of chiral salen‐Mn(III) complexes featuring two tertiary amine units were synthesized and employed in the enantioselective epoxidation of unfunctionalized alkenes in the presence of pyridine N‐oxide and 2,6‐dimeth‐ ylpyridine N‐oxide as proximal ligands, respectively. Moderate to high enantioselectivity and acceptable yields were achieved when NaClO was used as terminal oxidant under CH2Cl2/H2O biphasic media. Methyl iodide was found to be an effective additive to accelerate the epoxidation, possibly owing to the formation of quaternary ammonium units on catalysts, which may facilitate the reaction in an oil/water biphasic medium. The subsequent stimulation experiment was carried out, and the resulting ESI‐HRMS analysis revealed the formation of a novel (salen)manganese(III) intermediate featuring two quaternary ammonium units, and bearing a pyridine N‐oxide and a molecule of water simultaneously axially‐coordinated backbone.
Study on Synthesis and Binding Ability of a New Anion Receptor Containing NH Binding Sites
Authors: Qiao Yan‐Hong , Lin Hai , Lin Hua‐Kuan 
Published: May 2007

AbstractA new colorimetric recognition receptor 1 based on the dual capability containing NH binding sites of selectively sensing anionic guest species has been synthesized. Compared with other halide anions, its UV/Vis absorption spectrum in dimethyl sulfoxide showed the response toward the presence of fluoride anion with high selectivity, and also displayed dramatic color changes from colorless to yellow in the presence of TBAF (5×10−5 mol/L). The similar UV/Vis absorption spectrum change also occurred when 1 was treated with AcO− while a little change with H2PO−4 and OH−. Receptor 1 has almost not affinity abilities to Cl−, Br− and I−. The binding ability of receptor 1 to fluoride with high selectivity over other halides contributes to the anion size and the ability of forming hydrogen bonding. While the different ability of binding with geometrically triangular (AcO−), tetrahedral (H2PO−4) and linear (OH−) anions maybe result from their geometry configuration.
Thiourea Based Tweezer Anion Receptors for Selective Sensing of Fluoride Ions
Authors: Zhang You‐Ming , Cao Cheng , Wei Wei , Xie Tai‐Bao 
Published: May 2007

AbstractThree 3,3′‐di(4‐substituted‐phenyl)‐1,1′‐isophthaloylbis(thiourea) compounds were designed as novel neutral anion receptors, and synthesized by simple steps in good yields. The single crystal structure of receptor 1 shows that a solvent molecule was captured by the host molecule through intermolecular hydrogen bonding. Moreover, it was self‐assembled as a supramolecular system for the presence of abundant inter‐ and intramolecular hydrogen bonding and π‐π interactions between phenyl groups. Their application as anion receptors has been examined by UV‐Vis and 1H NMR spectroscopy, showing that they had a higher selectivity for fluoride than other halides. The host and guest formed a 1:1 stoichiometry complex through hydrogen bonding interactions in the first step, then following a process of deprotonation in presence of an excess of F− in the solvent of DMF.
Synthesis and Structural Characterization of 1,4‐Di(2‐methoxyphenyl)‐2,5‐piperazinedione
Authors: Zhang Shu‐Sheng , Wen Yong‐Hong , Tang Xiao‐Fang , Li Xue‐Mei 
Published: May 2007

AbstractA new derivative of 2,5‐piperazinedione, 1,4‐di(2‐methoxyphenyl)‐2,5‐piperazinedione (I), was synthesized by the cyclocondensation reaction of N‐2‐methoxyphenyl chloroacetamide, and its structure was characterized by elemental analysis, IR, 1H NMR and single crystal X‐ray diffraction method. The crystal belongs to monoclinic system, space group P21/c with unit cell dimensions a=0.56934(10) nm, b=1.3880(2) nm, c=1.00329(17) nm, β=90.376(3)°, V=0.7928(2) nm3, Z=2, Dc=1.367 g·cm−3, μ=0.98 cm−1, R and wR being 0.0606 and 0.1564 respectively for 1549 unique reflections with 1247 observed reflections [I>2σ(I)]. The molecule has a crystallographically imposed symmetry center. The three rings in the molecule are each coplanar with their attached groups, excluding methyl H atoms and the H atoms attached to the piperazinedione ring, while the whole molecule is not planar, with dihedral angles of 74.7(1)° between the piperazinedione and each of the two aromatic rings. The crystal structure is stabilized by van der Waals and dipole‐dipole forces.
Endogenous secretory receptor for advanced glycation endproducts as a novel prognostic marker in chondrosarcoma
Authors: Takeuchi Akihiko , Yamamoto Yasuhiko , Tsuneyama Koichi , Cheng Chunmei , Yonekura Hideto , Watanabe Takuo , Shimizu Katsuji , Tomita Katsuro , Yamamoto Hiroshi , Tsuchiya Hiroyuki 
Published: May 2007

AbstractBACKGROUNDChondrosarcoma, the second most frequent primary malignant bone tumor, is classified into 3 grades according to histologic criteria of malignancy. However, a low‐grade lesion can be difficult to distinguish from a benign enchondroma, whereas some histologically low‐grade lesions may carry a poor prognosis. The receptor for advanced glycation endproducts (RAGE) and its ligand, high‐mobility group box‐1 (HMGB1), was quantified in enchondromas and chondrosarcomas to determine whether these markers were associated with histological malignancy and prognosis.METHODSEnchondromas (n = 20) and typical chondrosarcomas (n = 39) were evaluated for RAGE, endogenous secretory RAGE (esRAGE, a splice variant form), and HMGB1 protein expression by immunohistochemistry including laser confocal microscopy. The content of esRAGE in resected specimens was measured with an enzyme‐linked immunosorbent assay. Associations of these molecules with histology and clinical behavior of tumors were analyzed.RESULTSExpression of esRAGE and HMGB1 was observed in all specimens. The numbers of cells positive for esRAGE and HMGB1 expression were positively associated with histologic grade. Expression of esRAGE was significantly higher in chondrosarcomas than in enchondromas (P < .001). Tissue esRAGE content was also significantly higher in grade 1 and 2 chondrosarcomas than enchondromas (P = .0255 and P = .008, respectively). High expression of esRAGE in grade 1 chondrosarcoma was associated with subsequent recurrence (P = .0013), lung metastasis (P = .0071), and poor survival (P < .001).CONCLUSIONSAssessment of esRAGE expression should aid in diagnostic andprognostic determinations in chondrosarcoma. Cancer 2007. © 2007 American Cancer Society.
Molecular Distortion Effect on ff‐Emission in a Pr(III) Complex with 4,7‐Diphenyl‐1,10‐Phenanthroline
Authors: Ishii Ayumi , Kishi Shinobu , Ohtsu Hideki , Iimori Toshifumi , Nakabayashi Takakazu , Ohta Nobuhiro , Tamai Naoto , Melnik Milan , Hasegawa Miki , Shigesato Yuzo 
Published: May 2007

AbstractThe electronic and structural behaviour of a Pr(III) complex with 4,7‐diphenyl‐1,10‐phenanthroline, [Pr(bathophen)2(NO3)3], is investigated with respect to the effect of configuration changes on the Pr(III) centre. [Pr(bathophen)2(NO3)3] luminesces from the excited states of the ligand and the metal ion. The fluorescence, ff‐emission (1D2→3H4), and phosphorescence bands appear at 394, 608.2 and 482 nm, respectively, in the solid state. In acetonitrile, the complex also shows multiple emissions. From the time‐resolved emission and the lifetime measurements, the excitation energy‐transfer in [Pr(bathophen)2(NO3)3] is clarified, that is, the upper excited triplet level of the ligand acts as an energy donor, while the 1D2 levels of Pr(III) is the acceptor. Additionally, the emission phenomena of the complex can be modified by molecular distortion, particularly by rotation of the phenyl groups in the ligand.
Atomic Layer Deposition of BaTiO3 Thin Films—Effect of Barium Hydroxide Formation
Authors: Vehkamäki M. , Hatanpää T. , Ritala M. , Leskelä M. , Väyrynen S. , Rauhala E. 
Published: May 2007

AbstractBarium titanate thin films are grown by atomic layer deposition (ALD) at 340 °C from barium cyclopentienyl and titanium methoxide precursors. H2O is used as the oxygen source. Binary reactions of Ba(tBu3C5H2)2 and H2O are first studied separately in BaO deposition and are found to result in a hydration/dehydration cycle, which is strongly influenced by the process temperature. Self‐limiting growth of amorphous barium titanate films becomes possible when Ti(OMe)4 – H2O growth cycles are mixed as well as possible with Ba(tBu3C5H2)2 – H2O cycles. The as‐deposited amorphous films are crystallized by post‐deposition annealing at 600 °C. Permittivities of 15 and 70 are measured for as‐deposited and post‐deposition annealed films, respectively. A charge density of 1.9 μC cm–2 (equivalent oxide thickness of 1.8 nm) and leakage current density ≤ 1 × 10–7 A cm–2 were achieved at 1 V bias with a 32 nm thick Ba–Ti–O film in a Pt electrode stack annealed at 600 °C.
Pulmonary metastasis of giant cell tumor of the bone diagnosed by fine‐needle aspiration biopsy
Authors: Cai Guoping , Ramdall Risha , Garcia Roberto , Levine Pascale 
Published: May 2007

AbstractGiant cell tumor is a benign but locally aggressive tumor that primarily affects the epiphyses of long bones of young adults. Pulmonary metastases in giant cell tumor are rare (about 1–9%). Here, we report a case of metastatic pulmonary giant cell tumor in a patient who had a previous history of giant cell tumor of the distal femur with multiple recurrences. The diagnosis of pulmonary metastasis was achieved by cytologic evaluation with concurrent immunohistochemical studies in material obtained by fine‐needle aspiration biopsy. The aspirate smears contained clustered and dispersed mononuclear and osteoclast‐like giant cells that had bland nuclei with inconspicuous nucleoli. All multinucleated cells showed immunoreactivity to KP‐1 antibody, a histiocytic marker (not lineage specific) and only a subset of mononuclear cells (30%) stained with this marker. Twenty percent of the mononuclear cells also displayed increased Ki‐67 and p53 protein expression. The pulmonary metastasis was similar morphologically and immunophenotypically to the recurrent giant cell tumor of the bone. Diagn. Cytopathol. 2007;35:358–362. © 2007 Wiley‐Liss, Inc.
Developmental characteristics of AMPA receptors in chick lumbar motoneurons
Authors: Ni Xianglian , Sullivan Grace J. , Martin‐Caraballo Miguel 
Published: May 2007

AbstractCa2+ fluxes through ionotropic glutamate receptors regulate a variety of developmental processes, including neurite outgrowth and naturally occurring cell death. In the CNS, NMDA receptors were originally thought to be the sole source of Ca2+ influx through glutamate receptors; however, AMPA receptors also allow a significant influx of Ca2+ ions. The Ca2+ permeability of AMPA receptors is regulated by the insertion of one or more edited GluR2 subunits. In this study, we tested the possibility that changes in GluR2 expression regulate the Ca2+ permeability of AMPA receptors during a critical period of neuronal development in chick lumbar motoneurons. GluR2 expression is absent between embryonic day (E) 5 and E7, but increases significantly by E8 in the chick ventral spinal cord. Increased GluR2 protein expression is correlated with parallel changes in GluR2 mRNA in the motoneuron pool. Electrophysiological recordings of kainate‐evoked currents indicate a significant reduction in the Ca2+‐permeability of AMPA receptors between E6 and E11. Kainate‐evoked currents were sensitive to the AMPA receptor blocker GYKI 52466. Application of AMPA or kainate generates a significant increase in the intracellular Ca2+ concentration in E6 spinal motoneurons, but generates a small response in older neurons. Changes in the Ca2+‐permeability of AMPA receptors are not mediated by age‐dependent changes in the editing pattern of GluR2 subunits. These findings raise the possibility that Ca2+ influx through Ca2+‐permeable AMPA receptors plays an important role during early embryonic development in chick spinal motoneurons. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Health service utilization for eating disorders: Findings from a community‐based study
Authors: Mond Jonathan M. , Hay Phillipa J. , Rodgers Bryan , Owen Cathy 
Published: May 2007

AbstractBackground:Prior use of health services was examined in a community sample of women with bulimic‐type eating disorders.Method:Participants (n = 159) completed a structured interview for the assessment of eating disorder psychopathology as well as questions concerning treatment‐seeking and type of treatment received.Results:Whereas a minority (40.3%) of participants had received treatment for an eating problem, most had received treatment for a general mental health problem (74.2%) and/or weight loss (72.8%), and all had used one or more self‐help treatments. Where treatment was received for an eating or general mental health problem, this was from a primary care practitioner in the vast majority of cases. Only half of those participants who reported marked impairment associated with an eating problem had ever received treatment for such a problem and less than one in five had received such treatment from a mental health professional.Conclusion:Women with bulimic‐type eating disorders rarely receive treatment for an eating problem, but frequently receive treatment for a general mental health problem and/or for weight loss. The findings underscore the importance of programs designed to improve the detection and management of eating disorders in primary care. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007
The use of guidelines for dissemination of “best practice” in primary care of patients with eating disorders
Authors: Currin Laura , Waller Glenn , Treasure Janet , Nodder Jane , Stone Christine , Yeomans Maria , Schmidt Ulrike 
Published: May 2007

AbstractObjective:A number of sets of clinical guidelines have been developed for the treatment of eating‐disordered patients. This study aimed to measure adherence to such guidance among family physicians working in primary care settings.Method:In the wake of the publication of national guidelines for “best practice,” family physicians in a large but diverse geographical region of the UK (population of 6.4 million) were approached and asked to complete a two‐stage survey.Results:Only 4% of these clinicians report using published guidelines or protocols, and none used the national guidelines that were available. Nor were these clinicians using the spirit of the guidelines, as there was little correspondence between recommended and actual treatment behavior.Conclusion:These findings suggest that specialist eating disorders services should not rely on guidelines to ensure the dissemination of best practice for these patients in primary care. Alternative means of dissemination are needed, and suggestions are made. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007
Differential role of IL‐2R signaling for CD8+ T cell responses in acute and chronic viral infections
Authors: Bachmann Martin F. , Wolint Petra , Walton Senta , Schwarz Katrin , Oxenius Annette 
Published: May 2007

AbstractIL‐2 is a cytokine with multiple and even divergent functions; it has been described as a key cytokine for in vitro T cell proliferation but is also essential for down‐regulating T cell responses by inducing activation‐induced cell death as well as regulatory T cells. The in vivo analysis of IL‐2 function in regulating specific T cell responses has been hampered by the fact that mice deficient in IL‐2 or its receptors develop lymphoproliferative diseases and/or autoimmunity. Here we generated chimeric mice harboring both IL‐2R‐competent and IL‐2R‐deficient T cells and assessed CD8+ T cell induction, function and maintenance after acute or persistent viral infections. Induction and maintenance of CD8+ T cells were relatively independent of IL‐2R signaling during acute/resolved viral infection. In marked contrast, IL‐2 was crucial for secondary expansion of memory CD8+ T cells and for the maintenance of virus‐specific CD8+ T cells during persistent viral infections. Thus, depending on the chronicity of antigen exposure, IL‐2R signaling is either essential or largely dispensable for induction and maintenance of virus‐specific CD8+ T cell responses.
US health services employment: A time series analysis
Authors: Kendix Michael , Getzen Thomas E. 
Published: May 2007

AbstractThe growth of health services employment in the United States is modelled using ARIMA analysis, and related to the growth in total U.S. employment. It is argued that specific features of the medical care sector (licensed professional manpower, non‐profit firms, third‐party financing) create institutional rigidities which delay adjustment to macroeconomic conditions and other shocks. Tests of Granger causality and the pattern of coefficients in the cross‐correlation function show that health services employment does lag other sectors of the economy by an average of 2 to 4 years. A Box‐Jenkins transfer‐noise function model between total and health employment is constructed and evaluated, and the impact dynamics of adjustment to Medicare and Medicaid are estimated.
Inpatient and outpatient health care demand in Cairo, Egypt
Authors: Ellis Randall P. , McInnes D. Keith , Stephenson Elizabeth H. 
Published: May 2007

AbstractThis paper uses the results of a household survey conducted in Cairo, Egypt in 1992 to examine the factors that influence the demand for inpatient and outpatient health services. Multi‐stage discrete choice models of the demand for health care, which identify the importance of individual, household, and facility level variables on each treatment decision, are estimated separately for outpatients and inpatients. Consumers are assumed to decide whether to seek any treatment and then choose between three categories of providers: a large public hospital (Embaba Hospital), all other public providers, and private/charitable providers. The results confirm that more affluent consumers prefer the higher cost, higher quality private and charitable hospitals. Age, sex, education, and insurance are also found to strongly impact the use of medical services. The results are suggestive but do not conclusively show that inpatient care is less price responsive than outpatient care. Price responsiveness of inpatient and outpatient demand are imprecisely estimated because price is highly correlated with quality, and the available data on facility quality do not permit us to adequately control for quality variations across facilities.