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Same Strategy (same + strategy)
Selected AbstractsElectoral System Reform in Democracy's Grey Zone: Lessons from Putin's RussiaGOVERNMENT AND OPPOSITION, Issue 4 2007Bryon Moraski Besides seat maximization, what factors motivate an incumbent regime in the grey zone between democracy and dictatorship to alter a relatively institutionalized parliamentary electoral system? To answer this question, this article seeks to uncover the rationale guiding the 2005 changes to Russia's electoral system. It presents evidence to suggest that the same strategies that allowed Russia's current party of power to use the existing electoral system to its advantage in the 2003 Duma election, threatened to spoil the fruits of that advantage in the years to come. Yet it also points out that moving from a mixed electoral system to a purely proportional system could be good for Russian democracy in the future. As a result, the work contends that seemingly authoritarian incumbents will promote reforms that aid the future cause of democracy when these same reforms serve their more immediate interests. [source] Cationic Polyelectrolyte Amplified Bead Array for DNA Detection with Zeptomole Sensitivity and Single Nucleotide Polymorphism SelectivityADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Chun Wang Abstract A highly sensitive strand specific DNA assay, which consists of a peptide nucleic acid (PNA) probe, a cationic conjugated polymer (PFVP), and self-assembled polystyrene beads in microwell arrays on silicon chip, is reported. PFVP, as an efficient signal amplifier and signal reporter, has been specially designed and synthesized to be compatible with commercial confocal microscopes for sensing on solid substrates. The assay operates on the net increase in negative charge at the PNA surface that occurs upon single-stranded DNA hybridization, which subsequently allows complex formation with the positively charged PFVP to favor energy transfer between the polymer and Cy5-labeled target. With maximized surface contact provided by bead arrays and signal amplification provided by PFVP, this assay allows detection of ,300 copies of Cy5-labeled DNA using a commercial confocal microscope. In addition, the same strategy is also extended for label-free DNA detection with a detection sensitivity of 150 attomole. Excellent discrimination against single nucleotide polymorphism (SNP) is also demonstrated for both Cy5-labeled and label-free target detection. This study indicates that cationic conjugated polymers have great potential to be incorporated into the widely used microarray technology for simplified process with improved detection sensitivity. [source] The polypeptide chain release factor eRF1 specifically contacts the s4UGA stop codon located in the A site of eukaryotic ribosomesFEBS JOURNAL, Issue 10 2001Laurent Chavatte It has been shown previously [Brown, C.M. & Tate, W.P. (1994) J. Biol. Chem.269, 33164,33170.] that the polypeptide chain release factor RF2 involved in translation termination in prokaryotes was able to photocrossreact with mini-messenger RNAs containing stop signals in which U was replaced by 4-thiouridine (s4U). Here, using the same strategy we have monitored photocrosslinking to eukaryotic ribosomal components of 14-mer mRNA in the presence of , and 42-mer mRNA in the presence of tRNAAsp (tRNAAsp gene transcript). We show that: (a) both 14-mer and 42-mer mRNAs crossreact with ribosomal RNA and ribosomal proteins. The patterns of the crosslinked ribosomal proteins are similar with both mRNAs and sensitive to ionic conditions; (b) the crosslinking patterns obtained with 42-mer mRNAs show characteristic modification upon addition of tRNAAsp providing evidence for appropriate mRNA phasing onto the ribosome. Similar changes are not detected with the 14-mer pairs; (c) when eukaryotic polypeptide chain release factor 1 (eRF1) is added to the ribosome·tRNAAsp complex it crossreacts with the 42-mer mRNA containing the s4UGA stop codon located in the A site, but not with the s4UCA sense codon; this crosslink involves the N-terminal and middle domains of eRF1 but not the C domain which interacts with eukaryotic polypeptide chain release factor 3 (eRF3); (d) addition of eRF3 has no effect on the yield of eRF1,42-mer mRNA crosslinking and eRF3 does not crossreact with 42-mer mRNA. These experiments delineate the in vitro conditions allowing optimal phasing of mRNA on the eukaryotic ribosome and demonstrate a direct and specific contact of ,core' eRF1 and s4UGA stop codon within the ribosomal A site. [source] Reactive Template Method to Synthesize Gold Nanoparticles with Controllable Size and Morphology Supported on Shells of Polymer Hollow Microspheres and Their Application for Aerobic Alcohol Oxidation in WaterADVANCED FUNCTIONAL MATERIALS, Issue 7 2009Jie Han Abstract A novel method has been developed to synthesize gold nanoparticles with tunable size and morphology supported on both inner and outer surfaces of poly(o -phenylenediamine) (PoPD) hollow microspheres, which act as both reductant and template/stabilizer. The size of gold nanoparticles supported on shells of PoPD hollow microspheres can be tuned from 3 to 15,nm by changing the concentration of the gold source, HAuCl4. Gold nanorods supported on shells of PoPD hollow microspheres can also be fabricated by introducing a well-known seed-growth strategy. In addition, silver nanoparticles supported on shells of PoPD hollow microspheres can also be successfully fabricated using the same strategy, which indicates the diversity of this proposed method for polymer hollow microspheres supporting noble metal nanoparticles. The products are characterized by X-ray diffraction and contact angle analysis. Furthermore, the catalytic activity of the obtained PoPD-microsphere-supported gold nanoparticles for aerobic alcohol oxidation is investigated. The results demonstrate that such polymer-supported gold nanoparticles can be used as reusable catalysts with high catalytic activity for aerobic alcohol oxidation in water. [source] Cost-effectiveness of primary cytology and HPV DNA cervical screeningINTERNATIONAL JOURNAL OF CANCER, Issue 2 2008Peter Bistoletti Abstract Because cost-effectiveness of different cervical cytology screening strategies with and without human papillomavirus (HPV) DNA testing is unclear, we used a Markov model to estimate life expectancy and health care cost per woman during the remaining lifetime for 4 screening strategies: (i) cervical cytology screening at age 32, 35, 38, 41, 44, 47, 50, 55 and 60, (ii) same strategy with addition of testing for HPV DNA persistence at age 32, (iii) screening with combined cytology and testing for HPV DNA persistence at age 32, 41 and 50, iv) no screening. Input data were derived from population-based screening registries, health-service costs and from a population-based HPV screening trial. Impact of parameter uncertainty was addressed using probabilistic multivariate sensitivity analysis. Cytology screening between 32 and 60 years of age in 3,5 year intervals increased life expectancy and life-time costs were reduced from 533 to 248 US Dollars per woman compared to no screening. Addition of HPV DNA testing, at age 32 increased costs from 248 to 284 US Dollars without benefit on life expectancy. Screening with both cytology and HPV DNA testing, at ages 32, 41 and 50 reduced costs from 248 to 210 US Dollars with slightly increased life expectancy. In conclusion, population-based, organized cervical cytology screening between ages 32 to 60 is highly cost-efficient for cervical cancer prevention. If screening intervals are increased to at least 9 years, combined cytology and HPV DNA screening appeared to be still more effective and less costly. © 2007 Wiley-Liss, Inc. [source] Immediate single-tooth implants in the anterior maxilla: a 1-year case cohort study on hard and soft tissue responseJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2008Tim De Rouck Abstract Aim: The objective of the present study was to assess implant survival rate, hard and soft tissue response and aesthetic outcome 1 year after immediate placement and provisionalization of single-tooth implants in the pre-maxilla. All patients underwent the same strategy, that is mucoperiosteal flap elevation, immediate implant placement, insertion of a grafting material between the implant and the socket wall and the connection of a screw-retained provisional restoration. Material and Methods: Thirty consecutive patients were treated for single-tooth replacement in the aesthetic zone by means of immediate implant placement and provisionalization. Reasons for tooth loss included caries, periodontitis or trauma. At 6 months, provisional crowns were replaced by the permanent ones. Clinical and radiographic evaluation was completed at 1, 3, 6 and 12 months to assess implant survival and complications, hard and soft tissue parameters and patient's aesthetic satisfaction. Results: One implant had failed at 1 month of follow-up, resulting in an implant survival rate of 97%. Radiographic examination yielded 0.98 mm mesial, respectively, 0.78 mm distal bone loss. Midfacial soft tissue recession and mesial/distal papilla shrinkage were 0.53, 0.41and 0.31 mm, respectively. Patient's aesthetic satisfaction was 93%. Conclusions: The preliminary results suggest that the proposed strategy can be considered to be a valuable treatment option in well-selected patients. [source] Fluorine-18 labelling of oligonucleotides: Prosthetic labelling at the 5,-end using the N -(4-[18F]fluorobenzyl)-2-bromoacetamide reagentJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 12 2003B. Kuhnast Abstract Labelled oligonucleotides are new imaging tools to study gene expression at the nucleic acid and protein levels. We have previously developed a universal method to label oligonucleotides at their 3,-end with radiohalogens and particularly with fluorine-18, the most widely used positron-emitter, t1/2: 109.8 min. Using the same strategy, we herein report the fluorine-18 labelling of oligonucleotides at their 5,-end. A 18-mer 2,O-methyl modified oligoribonucleotide, bearing a phosphorothioate group at its 5,-end, was conjugated to our fluorine-18-labelled reagent N -(4-[18F]fluorobenzyl)-2-bromoacetamide. The whole synthetic procedure yielded up to 1 GBq of fluorine-18-labelled oligonucleotide with a specific radioactivity of 37,74 GBq/,mol in 160 min. Copyright © 2003 John Wiley & Sons, Ltd. [source] Synthesis of pathological and nonpathological human exon 1 huntingtinJOURNAL OF PEPTIDE SCIENCE, Issue 7 2010David Singer Abstract Huntington's disease (HD) is a neurodegenerative disorder that affects approximately 1 in 10 000 individuals. The underlying gene mutation was identified as a CAG-triplet repeat expansion in the gene huntingtin. The CAG sequence codes for glutamine, and in HD, an expansion of the polyglutamine (poly-Q) stretch above 35 glutamine residues results in pathogenicity. It has been demonstrated in various animal models that only the expression of exon 1 huntingtin, a 67-amino acid-long polypeptide plus a variable poly-Q stretch, is sufficient to cause full HD-like pathology. Therefore, a deeper understanding of exon 1 huntingtin, its structure, aggregation mechanism and interaction with other proteins is crucial for a better understanding of the disease. Here, we describe the synthesis of a 109-amino acid-long exon 1 huntingtin peptide including a poly-Q stretch of 42 glutamines. This microwave-assisted solid phase peptide synthesis resulted in milligram amounts of peptide with high purity. We also synthesized a nonpathogenic version of exon 1 huntingtin (90-amino acid long including a poly-Q stretch of 23 glutamine residues) using the same strategy. In circular dichroism spectroscopy, both polypeptides showed weak alpha-helical properties with the longer peptide showing a higher helical degree. These model peptides have great potential for further biomedical analyses, e.g. for large-scale pre-screenings for aggregation inhibitors, further structural analyses as well as protein,protein interaction studies. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. [source] The synthesis of oligomers of oxetane-based dipeptide isosteres derived from L -rhamnose or D -xyloseJOURNAL OF PEPTIDE SCIENCE, Issue 6 2005Stephen W. Johnson Abstract Routes to oligomers (dimers, tetramers, hexamers) of five oxetane-based dipeptide isosteres have been established. Methyl 2,4-anhydro-5-azido-5-deoxy- L -rhamnonate ,monomer' led, by coupling the corresponding carboxylic acid and amine, to a ,dimer'. Reverse-aldol ring-opening occurred on attempted saponification of the dimer, so all further oligomerization was performed using TBDMS C-3 hydroxyl protection. The silyl protected L -rhamnonate monomer led in turn to the dimer (via the monomer acid and amine), the tetramer (via the dimer acid and amine) and finally the hexamer (via the tetramer acid and dimer amine). In each case the acids were obtained through saponification of the respective methyl esters and the amines were obtained by hydrogenation of the azides; coupling was TBTU-mediated. Essentially the same strategy was employed on equivalent D -lyxonate, 6-deoxy- L -altronate, 6-deoxy- D -gulonate and D -fuconate dipeptide isosteres to give the respective dimers, tetramers and hexamers. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd. [source] Hepatocellular carcinoma: Ablate and wait versus rapid transplantationLIVER TRANSPLANTATION, Issue 8 2010John P. Roberts This opinion piece explores an "ablate and wait" strategy for improving the 5-year recurrence-free outcome of liver transplantation in patients with hepatocellular carcinoma. The Milan criteria delimit by tumor size and number a population of patients who have good survival after liver transplantation. The University of California San Francisco downstaging experience has shown that patients with a tumor burden outside the Milan criteria who undergo tumor ablation and a period of waiting have outcomes that rival those of patients who undergo transplantation within the Milan criteria because the tumor biology is allowed to become apparent by radiological studies during the waiting period. This experience has led to 2 conclusions: first, expansion beyond the Milan criteria should not occur without therapy directed to the tumor followed by a period of waiting to decrease the risk of recurrence, and second, for tumors within the Milan criteria, the same strategy should be considered. Liver Transpl, 2010. © 2010 AASLD. [source] Stretching the Effectiveness of Analogical Training in Negotiations: Teaching Diverse Principles for Creating ValueNEGOTIATION AND CONFLICT MANAGEMENT RESEARCH, Issue 2 2008Simone Moran Abstract The present research adapts analogical training to teach negotiators broad concepts of creating value. Recent research has shown specific analogical training, wherein negotiators draw analogies between different cases involving the same strategy, to be effective for learning and transferring specific value-creating strategies. The current results endorse the approach that analogical training can be a valuable tool for teaching negotiation, but argue that it can be enhanced by considering the breadth of the negotiation concepts that are learned. Diverse analogical training, wherein negotiators compare several different value-creating strategies, was shown to be more effective for learning broad underlying value-creating principles. This method facilitated transfer to a distinctive task and improved performance on a variety of value-creating strategies, including some that were not previously trained. The improved performance was also accompanied by enhanced understanding of the potential to create value. [source] | |||||||||||||