bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Planar—Chiral Heterocycles as Enantioselective Organocatalysts
Authors: Fu Gregory C. 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation of 2‐Aminobenzothiazole Derivatives
Authors: Kumar Vikash , Singh Balvinder 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Hydroamination Reactions by Metal Triflates: Broensted Acid versus Metal Catalysis?
Authors: Taylor Jason G. , Adrio Luis A. , Hii King Kuok 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Materials Used for Organic Light‐Emitting Diodes: Organic Electroactive Compounds
Authors: Petrova P. , Tomova R. 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Small‐Molecule Inhibitors of the Hedgehog Signaling Pathway as Cancer Therapeutics
Authors: Peukert Stefan , Miller‐Moslin Karen 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation and Characterization of Super‐Hydrophobic Surfaces
Authors: Crick Colin R. , Parkin Ivan P. 
Published: June 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Surface‐functionalized Carbon Black as Catalyst for the Direct Production of Hydrogen Peroxide by the Oxidation of Hydroxylamine
Authors: Song Wei , Li Yong , Guo Xiaohui , Li Juan , Shen Wenjie 
Published: June 2010

AbstractCarbon black (CB) without micropores was functionalized by mixed acid and used to explore the surface chemistry effect on the production of hydrogen peroxide (H2O2). The CB materials were characterized by N2 adsorption‐desorption, XRD, SEM, FTIR, and TPD. The results of different characterization methods indicated that both the textural features and the surface chemical properties of CB were significantly modified by the acidic treatment. The catalytic performance of the modified CBs for hydroxylamine (NH2OH) oxidation increased with increasing the surface oxygen‐containing species. The yield of H2O2 approached 30% with the corresponding concentration of 73.9 mmol·L−1 (w=0.25%) over the most promising CB catalyst, which was much superior to the results obtained on supported noble metals. Correlations between catalytic activity and concentration of different surface functional groups on the CB samples confirmed that the quinonoid species might be the active species.
Phenylacetylene Dendrimers Containing a Fluorene Core: Synthesis and Spectroscopic Studies
Authors: Wang Chengyun , Zhong Hanbin , Li Shanshan , Shu Weifu , Shen Yongjia 
Published: June 2010

AbstractPhenylacetylene dendrimers 9–11 containing fluorene as the core with a larger HOMO‐LUMO energy gap were synthesized and characterized. Their structure and properties were studied by UV, FL, 1H NMR, MS etc. These novel phenylacetylene dendrimers exhibit unique photophysical properties. They exist a new absorption band around 340 nm whose molar coefficient decreases with increasing generation. The band‐gaps of 9–11 are 3.54, 3.43 and 3.02 respectively. The fluorescence quantum yield of 10 is as high as 0.61.
Kinetics and Mechanism Investigation of the Reaction between Triphenylphosphine, Di‐tert‐butyl Acetylenedicarboxilate and OH‐Acid
Authors: Habibi‐Khorassani Sayyed Mostafa , Ebrahimi Ali , Maghsoodlou Malek Taher , Kazemian Mohammad Amin , Moradian Majed 
Published: June 2010

AbstractKinetic studies were made for the reaction between triphenylphosphine, di‐tert‐butyl acetylenedicarboxilate in the presence of OH‐acid, such as 2‐hydroxy‐4‐methoxybenzaldehyde. To determine the kinetic parameters of the reaction, it was monitored by UV spectrophotometery. The second order fits were automatically drawn by the software associated with a Cary UV spectrophotometer model Bio‐300 at appropriate wavelength. The values of the second order rate constant (k2) were calculated using standard equations within the program. At the temperature range studied the dependence of the second order rate constant (ln k2) on reciprocal temperature was in a good agreement with Arrhenius equation. This provided the relevant plots to calculate the activation energy of the reaction. Furthermore useful information was obtained from studies of the effect of solvent and concentration of reactants on the rate of reaction. Proposed mechanism was confirmed according to the obtained results and steady state approximation and first step (k2) of reaction was recognized as a rate‐determining step on the basis of experimental data. In addition, assignment of more stable isomers (Z or E) was investigated using the theoretical study.
Formation of Human Telomeric G‐quadruplex Structures Induced by the Quaternary Benzophenanthridine Alkaloids: Sanguinarine, Nitidine, and Chelerythrine
Authors: Yang Shu , Xiang Junfeng , Yang Qianfan , Li Qian , Zhou Qiuju , Zhang Xiufeng , Tang Yalin , Xu Guangzhi 
Published: June 2010

AbstractThe ligands which can facilitate the formation and stabilize G‐quadruplex structures have attracted enormous attention due to their potential ability of inhibiting the telomerase activity and halting tumor cell proliferation. It is noteworthy that the abilities of the quaternary benzophenanthridine alkaloids (QBAs), the very important G‐quadruplex binders, in inducing the formation of human telomeric DNA G‐quadruplex structures, have not been reported. Herein, the interaction between single‐strand human telomeric DNA and three QBAs: Sanguinarine (San), Nitidine (Nit) and Chelerythrine (Che), has been investigated. Although these molecules are very similar in structure, they exhibit significantly different abilities in inducing oligonucleotide d(TTAGGG)4 (HT4) to specific G‐quadruplex structures. Our experimental results indicated that the best ligand San could convert HT4 into antiparallel G‐quadruplex structure completely, followed by Nit, which could transform to mixed‐type or hybrid G‐quadruplex structure partially, whereas Che could only transform to antiparallel G‐quadruplex structure in small quantities. The relative QBAs' inducing abilities as indicated by the CD data are in the order of San>Nit>Che. Further investigation revealed that the G‐quadruplex structures from HT4 induced by QBAs are of intramolecular motif. And only sequences with certain length could be induced by QBAs because of their positive charges which could not attract short chain DNA molecules to close to each other and form intermolecular G‐quadruplex. In addition, the factors that affect the interaction between HT4 and QBAs were discussed. It is proposed that the thickness of the molecular frame and the steric hindrance are the primary reasons why the subtle differences in QBAs' structure lead to their remarkable differences in inducing the formation of the G‐quadruplex structures.
A Facile and Clean Synthesis of Pyrimidine Derivatives via Three‐component Reaction in Aqueous Media
Authors: Shi Daqing , Shi Jinwen , Rong Shaofeng 
Published: June 2010

AbstractA series of 5‐benzylidenepyrimidine‐2,4,6(1H,3H,5H)‐trione and 5,5′‐(arylmethylene) bis[6‐aminopyrimidine‐ 2,4(1H,3H)‐dione] derivatives were synthesized via the three‐component reactions of aromatic aldehyde, 6‐aminopyrimidine‐2,4‐dione and Medrum's acid in aqueous media in the presence of triethylbenzylammonium chloride. The structures of the products were affected by substituents of aromatic aldehydes.
Multiplexed p53 Mutation Detection by Microchip Electro‐phoresis with Laser‐Induced Fluorescence Detector
Authors: Li Gang , Ge Shuli , Ni Xiaofang , Wang Qingjiang , He Pinjiang , Fang Yuzhi 
Published: June 2010

AbstractA form of single‐strand DNA‐conformation polymorphism analysis (SSCP) employing nondenaturing slab gel electrophoresis is applicable to the genetic diagnosis of mutations at exons 7, 8 and 9 of the p53 gene. Recently, microchip electrophoresis (ME) systems have been used in SSCP analysis instead of conventional slab gel electrophoresis in terms of speed, sensitivity and automation. The aim of the present study was to investigate the application of SSCP and ME analysis as a rapid and effective method to the detection of mutations for exons 7, 8 and 9 of the p53 gene. It was found that using the electric field strength 260 V/cm and the sieving matrix of 4 mg/mL poly(ethylene oxide) was very useful to achieve better resolution and fast detection of mutations at exons 7, 8 and 9 of p53 gene. Under the optimized conditions, mutations at exons 7–9 of p53 gene were analyzed within 60 s and the relative standard deviation values of the migration times were less than 5.81% (n=5). The detection limit can be as low as 1 ng·L−1.
Theory of Microbial Carbonate Precipitation and Its Application in Restoration of Cement‐based Materials Defects
Authors: Qian Chunxiang , Wang Ruixing , Cheng Liang , Wang Jianyun 
Published: June 2010

AbstractBacterial induced carbonate mineralization has been demonstrated as a new potential method for restoration of limestones in historic buildings and monuments. We claim here the formation of calcium carbonate was controlled by extracellular polymeric substances (EPS) isolated from Bacillus pasteurii. The process of crystallization nucleation was accelerated in the presence of cells and inhibited in the presence of EPS. The CaCO3 film deposited on cement paste surface was about 100 µm after 7 d treatment. The results of various restoring methods showed that higher decrease of water absorption of cement paste was gained in brushing application in the presence of agar, which could maintain urease with high activity in long term compared to spraying method. The coefficient of capillary suction of cement paste treated with brushing method was reduced by 90%. Mixed media consisted of sands, urea, Ca2+ and concentrated biomass, was injected into artificial cracks of cement paste followed by continual nutrient supplement, and CaCO3 particles were precipitated gradually between sands particles which were combined with cement matrix. The results showed that the compressive strength of recovered specimens was restored to 84%, which demonstrated that this kind of bio‐restoration method is effective in repairing surface defects of cement‐based materials.
Novel Monocyclam Derivatives as HIV Entry Inhibitors: Design, Synthesis, Anti‐HIV Evaluation, and Their Interaction with the CXCR4 Co‐receptor
Authors: Pettersson Sofia , Pérez‐Nueno Violeta I. , Mena Maria Pau , Clotet Bonaventura , Esté José A. , Borrell José I. , Teixidó Jordi 
Published: June 2010

AbstractThe CXCR4 receptor has been shown to interact with the human immunodeficiency virus (HIV) envelope glycoprotein gp120, leading to fusion of viral and cell membranes. Therefore, ligands that can attach to this receptor represent an important class of therapeutic agents against HIV, thus inhibiting the first step in the cycle of viral infection: the virus–cell entry/fusion. Herein we describe the in silico design, synthesis, and biological evaluation of novel monocyclam derivatives as HIV entry inhibitors. In vitro activity testing of these compounds in cell cultures against HIV strains revealed EC50values in the low micromolar range without cytotoxicity at the concentrations tested. Docking and molecular dynamics simulations were performed to predict the binding interactions between CXCR4 and the novel monocyclam derivatives. A binding mode of these compounds is proposed which is consistent with the main existing site‐directed mutagenesis data on the CXCR4 co‐receptor. Moreover, molecular modeling comparisons were performed between these novel monocyclams, previously reported non‐cyclam compounds from which the monocyclams are derived, and the well‐known AMD3100 bicyclam CXCR4 inhibitors. Our results suggest that these three structurally diverse CXCR4 inhibitors bind to overlapping but not identical amino acid residues in the transmembrane regions of the receptor.
Risk factors for central venous catheter thrombotic complications in children and adolescents with cancer
Authors: Revel‐Vilk S. , Yacobovich J. , Tamary H. , Goldstein G. , Nemet S. , Weintraub M. , Paltiel O. , Kenet G. 
Published: June 2010

AbstractBACKGROUND:The use of central venous catheters (CVCs) has greatly improved the quality of care in children with cancer, yet these catheters may cause serious infectious and thrombotic complications. The aim of this prospective registry study was to assess the host and CVC‐related risk factors for CVC‐created thrombotic complications.METHODS:Patients undergoing CVC insertion for chemotherapy were followed prospectively for CVC complications. At the time of enrollment, demographic, clinical, and CVC‐related data, and family history of thrombosis were collected. Survival and Cox regression analyses were performed.RESULTS:A total of 423 CVCs were inserted into 262 patients for a total of 76,540 catheter days. The incidence of CVC‐related deep‐vein thrombosis (DVT) was 0.13 per 1000 catheter‐days (95% confidence interval [CI], 0.06‐0.24). Insertion of peripherally inserted central catheters (PICCs) and insertion in an angiography suite significantly increased the risk of symptomatic CVC‐related DVT. The incidence of CVC occlusion was 1.35 per 1000 catheter‐days (95% CI, 1.1‐1.63). Positive family history of thrombosis significantly increased the risk of CVC occlusion (hazard ratio [HR], 2.16; 95% CI, 1.2‐3.8). The CVC‐related risk factors were insertion of Hickman catheters, insertion in angiography suite, and proximal‐tip location. Patients developing at least 1 episode of both CVC occlusion and infection had an increased risk for developing symptomatic CVC‐related DVT (HR, 4.15; 95% CI, 1.2‐14.4).CONCLUSIONS:Both patient‐related and CVC‐related factors are associated with higher risk of symptomatic thrombotic complications. These risk factors could be used in the clinical setting and in developing future studies for CVC thromboprophylaxis. Cancer 2010. © 2010 American Cancer Society.
Quantitative DNA methylation analysis detects cervical intraepithelial neoplasms type 3 and worse
Authors: Lai Hung‐Cheng , Lin Ya‐Wen , Huang Rui‐Lan , Chung Ming‐Tzeung , Wang Hui‐Chen , Liao Yu‐Ping , Su Po‐Hsuan , Liu Yung‐Liang , Yu Mu‐Hsien 
Published: June 2010

AbstractBACKGROUND:DNA methylation may be used a potential biomarker for detecting cervical cancer. The authors of this report used quantitative methylation analysis of 4 genes in a full spectrum of cervical lesions to test its potential clinical application.METHODS:This hospital‐based, retrospective, case‐control study was conducted in 185 patients and included patients who had a normal uterine cervix (n = 53), cervical intraepithelial neoplasm type 1 (CIN1) (n = 37), CIN2 (n = 22), CIN3 (n = 24), carcinoma in situ (CIS) (n = 22), squamous cell carcinoma (SCC, n = 20), and adenocarcinoma (AC) (n = 7). Methylation levels of the genes sex‐determining region Y, box 1 (SOX1); paired box gene 1 (PAX1); LIM homeobox transcription factor 1α (LMX1A), and NK6 transcription factor‐related locus 1 (NKX6‐1) were determined by using real‐time methylation‐specific polymerase chain reaction (PCR) amplification. Cutoff values of the percentage of methylation reference (PMR) for different diagnoses were determined to test the sensitivity and specificity and to generate receiver operating characteristic (ROC) curves. Two‐sided Mann‐Whitney U tests were used to test differences in PMR between groups.RESULTS:The PMRs of the 4 genes were significantly higher in CIN3 and worse (CIN3+) lesions than the PMRs in specimens of normal cervix and CIN1 or CIN2 (P < .001). ROC curve analysis demonstrated that the sensitivity, specificity, and accuracy for detecting CIN3+ lesions were 0.88, 0.82, and 0.95, respectively, for SOX1; 0.78, 0.91, and 0.89, respectively, for PAX1; 0.77, 0.88, and 0.90, respectively, for LMX1A; and 0.93, 0.97, and 0.97, respectively, for NKX6‐1.CONCLUSIONS:The current results indicated that quantitative PCR‐based testing for DNA methylation of 4 genes holds great promise for cervical cancer screening and warrants further population‐based studies using standardized DNA methylation testing. Cancer 2010. © 2010 American Cancer Society.
Evolvable hardware design based on a novel simulated annealing in an embedded system
Authors: He Guoliang , Xiong Naixue , Yang Laurence T. , Kim Tai‐hoon , Hsu Ching Hsien , Li Yuanxiang , Hu Ting 
Published: June 2010

SUMMARYThe auto‐design of electronic circuits for the next generation Information Technology (IT) computing environments is currently one of the most extensively studied issues in the field of evolvable hardware (EHW) architectures. It aims to improve the reliability and fault‐tolerance of hardware systems using embedded techniques. As the scalability of logic circuits becomes larger and more complex nowadays, its auto‐design is more and more difficult. In order to improve the efficiency and the capability of digital circuit auto‐design, in this paper, a multi‐objective simulated annealing (MSA)‐based increasable evolution approach is proposed in an embedded system. First, an extended matrix encoding method is used to indicate the potential performance of a circuit. Therefore, the risk of deleting a circuit with a good developing potential during evolution can be reduced. Second, we consider each output of a digital circuit as an objective, and MSA is designed for digital logic circuits with gradual evolution scheme. In the process of evolution, each objective is evolved in parallel with adaptive mechanism of neighborhood and a performance evaluation. Finally, a framework of online evolution with macro‐blocks is employed to implement MSA on a field‐programmable gate array efficiently and securely. In our experiments, six arithmetic circuits are designed to assess the performance of MSA with gate‐level and function‐level approaches comparing to other algorithms. The comparison results show that our method is very efficient in the auto‐design of EHW. Copyright © 2010 John Wiley & Sons, Ltd.
Performance modelling and analysis of Deficit Round Robin scheduling scheme with self‐similar traffic
Authors: Liu Lei , Jin Xiaolong , Min Geyong , Li Keqiu 
Published: June 2010

AbstractThe provisioning of fairness to various network applications is an important Quality‐of‐Service demand and has thus become a challenging research issue in contemporary communication networks. Deficit Round Robin (DRR) is a promising fair scheduling mechanism owing to its low complexity and excellent ability of achieving a good degree of fairness in terms of throughput. On the other hand, self‐similar traffic was found to be pervasively present in communication networks and has great impact on the performance of scheduling systems. However, to the best of our knowledge, there has not been any analytical model reported in the open literature for the DRR mechanism in the presence of self‐similar traffic. To fill this gap, this paper analytically investigates the queueing performance of DRR and develops a new analytical model for deriving the upper and lower bounds of the queue length distributions of individual traffic flows in DRR scheduling systems subject to self‐similar traffic. Extensive comparison between simulation and analytical results validates the accuracy of the developed model. To demonstrate its applications, the analytical model is used to investigate the effects of packet size on the performance of the queueing system. The developed model is further applied to study the configuration of weights of individual traffic flows. Copyright © 2010 John Wiley & Sons, Ltd.
Interactions between Oxygen Atoms on Pt(100): Implications for Ordering during Chemisorption and Catalysis
Authors: Liu Da‐Jiang , Evans James W. 
Published: June 2010

AbstractWe present a DFT analysis of the interactions between chemisorbed oxygen on the unreconstructed (1×1)‐Pt(100) surface. These interactions control ordering of O not just for single‐species adsorption, but also within O domains during coadsorption and reaction with other species such as CO. The calculations indicate that O prefers bridge sites, as deduced previously. In addition, we find a large difference in the interactions between O at different types of bridge site pairs separated by one lattice constant. There is strong repulsion for pairs separated by a Pt atom, but only a weak interaction for pairs separated by a fourfold hollow site. This finding elucidates the tendency for striped (n×1)‐O ordering often observed in chemisorption and reaction studies.
DNA Structural Changes Under Different Stretching Methods Studied By Molecular Dynamics Simulations
Authors: Qi Wenpeng , Lei Xiaoling , Fang Haiping 
Published: June 2010

AbstractWe present a molecular dynamics simulation study of 22‐mer DNA conformational variations obtained by stretching both 3′‐termini and both 5′‐termini. Stretching 3′‐termini by 3.5 nm required 142 kJ mol−1 and the force plateau was ∼80 pN, whereas stretching 5′‐termini by the same length required 190 kJ mol−1 and the force plateau was ∼100 pN. Stretching 3′‐termini led to a larger untwisting of the double helix and the successive base pairs rolled to the side of the DNA minor groove, while stretching 5′‐termini resulted in the base pairs rolling to the major groove side and reducing of the diameter of DNA molecule. The most distinctive difference between stretching 3′‐termini and 5′‐termini was that at the force plateau region stretching the 5′‐termini resulted in breakage of the base pairs, which considerably disturbed the structure of the DNA double helix. All of the variations of base rotation and translation for both stretching methods took place when the relative length of DNA l was longer than 1.2, which was the point the force plateau appeared.