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Scope
Kinds of Scope Terms modified by Scope Selected AbstractsGEOGRAPHIC SCALE AND FUNCTIONAL SCOPE IN METROPOLITAN GOVERNANCE REFORM: THEORY AND EVIDENCE FROM GERMANYJOURNAL OF URBAN AFFAIRS, Issue 2 2006Joachim K. Blatter New dichotomies emerge, for example, "jumping of scale" versus "relativation of scales"; "deterritorializiaton" versus "reterritorialization"; "spaces of place" versus "space of flows." These dichotomies can be interpreted as different proposals and/or diagnoses in respect to the geographic scale and functional scope of emerging institutions of metropolitan governance. The paper aims to trace the empirical question of which direction we are heading by analyzing recent metropolitan governance reforms in six West German metropolitan areas. The findings show that there is a general trend to create soft institutions of governance on a larger scale as a reaction to global competition and continental integration. Beyond this commonality, we discover quite different institutional trajectories. The regions which are strongly embedded in the global economy tend toward a "deterritorialized" form of metropolitan governance with rather weak institutions characterized by large geographic scales and functional specialization. In contrast, the regions which are not as much embedded in the global economy have been able to create strong governance institutions on a regional level characterized by a rather small geographic scope and based on a territorial logic of functional integration and geographic congruence. [source] THE SCOPE OF RATIONAL REQUIREMENTSTHE PHILOSOPHICAL QUARTERLY, Issue 238 2010John Brunero Niko Kolodny has argued that some (local) rational requirements are narrow-scope requirements. Against this, I argue here that all (local) rational requirements are wide-scope requirements. I present a new objection to the narrow-scope interpretations of the four specific rational requirements which Kolodny considers. His argument for the narrow-scope interpretations of these four requirements rests on a false assumption, that an attitude which puts in place a narrow-scope rational requirement somewhere thereby puts in place a narrow-scope rational requirement everywhere. My argument against Kolodny is analogous to arguments which use holism about reasons to defend moral particularism. [source] On the Scope and Truth of Theology: Theology as Symbolic Engagement , By Robert C. NevilleCONVERSATIONS IN RELIGION & THEOLOGY, Issue 1 2007George Newlands First page of article [source] Creating and Justifying Research and Development Value: Scope, Scale, Skill and Social Networking of R&DCREATIVITY AND INNOVATION MANAGEMENT, Issue 1 2002Aard J. Groen In this paper we describe a framework for analysing the creation and justification of Research & Development. The 4S framework is developed for analysing the scope, scale, skills and social network aspects of Research & Development value. The framework is based on social system theory, a process contingency model, and recent Research & Development metrics. We present a first empirical assessment based on a workshop using the 4S framework for leveraging Research & Development. Results that assist in the assessment of value creation utilising R & D within networks are very relevant in high tech industries. The multi,dimensional process approach of this framework seems promising for understanding and managing R&D value creation, but needs further operationalisation. Case studies are described and a Dutch network on leveraging R&D has been initiated. [source] THE MOLECULAR FUTURE IN CYTOLOGYCYTOPATHOLOGY, Issue 2006M. Salto-Tellez Molecular diagnosis is the application of molecular biology techniques and knowledge of the molecular mechanisms of disease to diagnosis, prognostication and treatment of diseases. Molecular Diagnosis is, arguably, the fastest growing area of diagnostic medicine. The US market for molecular testing generated $1.3 billion in 2000, which was predicted to increase to about $4.2 billion by 2007.1 We proposed the term Diagnostic Molecular Cytopathology to define the application of molecular diagnosis to cytopathology2. Diagnostic Molecular Cytopathology is essential for the following reasons: (i) Molecular testing is sometimes indispensable to establish an unequivocal diagnosis on cell preparations; (ii) Molecular testing provides extra information on the prognosis or therapy of diseases diagnosed by conventional cytology; (iii) Molecular testing provides genetic information on the inherited nature of diseases that can be directly investigated in cytology samples, by either exfoliation or by fine needle aspiration; (iv) Sometimes the cytopathology sample is the most convenient (or the only available) source of material for molecular testing; (v). Direct molecular interrogation of cells allows for a diagnostic correlation that would otherwise not be possible. Parallel to this direct diagnostic implication, cytopathology is increasing important in the validation of biomarkers for specific diseases, and in therefore of significant importance in the overall translational research strategies. We illustrate its application in some of the main areas of oncology molecular testing, such as molecular fingerprinting of neoplasms,3 lymphoreticular diseases,2 sarcomas4 and lung cancer,5 as well as translational research using diagnostic cytopathology techniques. The next years will see the consolidation of Diagnostic Molecular Cytopathology, a process that will lead to a change of many paradigms. In general, diagnostic pathology departments will have to reorganize molecular testing to pursue a cost-efficient operation. Sample preparation will have to take into account optimal preservation of nuclear acids. The training of technical staff and the level of laboratory quality control and quality assurance would have to follow strict clinical (not research) laboratory parameters. And, most importantly, those pathologists undertaking molecular diagnosis as a discipline would have to develop their professional expertise within the same framework of fellowships and professional credentials that is offered in other sub-specialties. The price to pay if this effort is not undertaken is too important for the future of diagnostic pathology in general. The increasing characterization of molecular biomarkers with diagnostic, prognostic or therapeutic value is making the analysis of tissue and cell samples prior to treatment a more complex exercise. If cytopathologists and histopathologists allow others to take charge of molecular diagnosis, our overall contribution to the diagnostic process will be diminished. We may not become less important, but we may become less relevant. However, those within the discipline of diagnostic pathology who can combine the clinical background of diseases with the morphological, immunocytochemical and molecular diagnostic interpretation will represent bona fide diagnostic specialists. Such ,molecular cytopathologists' would place themselves at the centre of clinical decision-making. Reference:, 1. Liz Fletcher. Roche leads molecular diagnostics charge. Nature Biotechnol 20, 6,7; 2002 2. Salto-Tellez M and Koay ESC. Molecular Diagnostic Cytopathology - Definitions, Scope and Clinical Utility. Cytopathology 2004; 15:252,255 3. Salto-Tellez M, Zhang D, Chiu LL, Wang SC, Nilsson B, and Koay ESC. Immunocytochemistry Versus Molecular Fingerprinting of Metastases. Cytopathology, 2003 Aug; 14(4):186,90. 4. Chiu LL, Koay SCE, Chan NL and Salto-Tellez M. Molecular Cytopathology: Sequencing of the EWS-WT1 Gene Fusion Transcript in the Peritoneal Effusion of a Patient with Desmoplastic Small Round Cell Tumour. Diagnostic Cytopathology, 2003 Dec; 29(6): 341,3. 5. TM Chin, D Anuar, R Soo, M Salto-Tellez, WQ Li, B Ahmad, SC Lee, BC Goh, K Kawakami, A Segal, B Iacopetta, R Soong. Sensitive and Cost-Effective deptection of epidermal growth factor Receptor Mutations in Small Biopsies by denaturing High Performance Liquid Chromatography. (In press). [source] Full Scope of Effect of Facial Lipoatrophy: A Framework of Disease UnderstandingDERMATOLOGIC SURGERY, Issue 8 2006BENJAMIN ASCHER MD BACKGROUND Facial lipoatrophy has been observed to occur in a variety of patient populations, with inherited or acquired disease, or even in aging patients as a natural progression of tissue change over time. There is currently no framework from which physicians of all medical specialties can communally discuss the manifestations, diagnoses, and management of facial lipoatrophy. OBJECTIVE The aim of this assembly was to derive a definition of facial lipoatrophy capable of being applied to all patient populations and develop an accompanying grading system. RESULTS The final consensus of the Facial Lipoatrophy Panel encompasses both aging and disease states: "Loss of facial fat due to aging, trauma or disease, manifested by flattening or indentation of normally convex contours." The proposed grading scale includes five gradations (Grades 1,5; 5 being the most severe), and the face is assessed according to three criteria: contour, bony prominence, and visibility of musculature. CONCLUSION Categorizing the presentation of facial lipoatrophy is subjective and qualitative, and will need to be validated with objective measures. Furthermore, during the assembly, several topics were exposed that warrant further research, including the physiology of volume loss, age and lipoatrophy, and human immunodeficiency virus and lipoatrophy. [source] An appreciation of Ronnie Mac Keith (1978)DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2008Martin Bax DM It is 100 years since Ronnie Mac Keith's birth and 50 years since he started the Journal Developmental Medicine & Child Neurology (DMCN; initially called The Cerebral Palsy Bulletin), the first number being a reprint of William Little's original article. Scope, then The Spastics Society, had just begun to raise significant sums of money and Ronnie persuaded them not only to put some money into medical research, which they did, funding the research laboratories at Guy's, but also, uniquely, to spend some money on educating and informing doctors. This led to financial backing, happily still continuing, to the publishers of DMCN, now the Mac Keith Press. Initially, it was published under the title Spastics International Medical Publications but this was a clumsy and difficult title because of the unfortunate use of the word 'spastics'and soon after Ronnie's death, who was then senior editor, the Mac Keith Press Board were delighted that his family agreed that the Press would be named after him. In the late 1950s and early 1960s, Ronnie was collecting a team around him to develop the Journal and the books, and contacted me because he knew I had literary interests. I didn't really want to edit a medical journal but I was interested in paediatrics so in the end I got involved! I worked very closely with Ronnie, both clinically and at the Mac Keith Press, and also with the Medical Education Information Unit of the Spastics Society on the meetings he ran. When he died, I tried to pull together something of Ronnie's nature in this personal memoir below, which supplemented the more formal statements about his life and career which can be found in the relevant number of the Journal.1 One hopes that Ronnie would be pleased with what we have done and I know that he would be hoping that we would continue for another 50 years developing ideas and approaches which were essentially developed by Ronnie Mac Keith. [source] 2-Substituted Benzo[b]furans from (E)-1,2-Dichlorovinyl Ethers and Organoboron Reagents: Scope and Mechanistic Investigations into the One-Pot Suzuki Coupling/Direct Arylation,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2010Laina M. Geary Abstract 2-Substituted benzo[b]furans can easily be assembled from simple phenols, boronic acids or other organoboron reagents, and trichloroethylene. The overall process requires only two synthetic steps, with the key step being a one-pot sequential Suzuki cross-coupling/direct arylation reaction. The method tolerates many useful functional groups and does not require the installation of any other activating functionality. The modular nature of the process permits the rapid synthesis of many analogues using essentially the same chemistry, of particular value in drug development. Results of kinetic isotope effect studies and investigations into the regioselectivity of the process indicate that the direct arylation step most likely does not involve an electrophilic palladation. The most likely mechanism lies somewhere on the continuum between a C,H bond metathesis and an assisted palladation or concerted metallation-deprotonation pathway. [source] Broadening the Synthetic Scope of the Iron(III)-Catalyzed Aza-Prins CyclizationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2010Rubén M. Carballo Abstract The nature and influence of the N -sulfonyl group in aza-Prins cyclization and the reactivity of the six-membered aza-cycle generated has been studied. The aza-Prins cyclization of ,,,-unsaturated amines with a tosyl group at the nitrogen atom produces 2-alkyl-4-halo-1-tosyl-1,2,5,6-tetrahydropyridines with a halovinyl function, extraordinarily stable to further derivatization and detosylation conditions. To modulate the reactivity of such aza-cycles, a general study of the aza-Prins cyclization reaction was performed with several sulfonamides. Ring formation occurs satisfactorily with both N -nosyl and N -mesylamines providing optimal conditions for further synthetic transformations. To exemplify the scope of this methodology, a short synthesis of the alkaloid coniine was successfully carried out. [source] Nd(OTf)3 -Catalyzed Cascade Reactions of Vinylidenecyclopropanes with Enynol: A New Method for the Construction of the 5,7,6 Tricyclic Framework and Its Scope and LimitationsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Liang-Feng Yao Abstract We report in this paper a Lewis acid [Nd(OTf)3]-catalyzed protocol to construct compounds containing a 5,7,6 tricyclic framework in good yield from readily accessible starting materials vinylidenecyclopropanes (VDCPs) 1 and enynols 2a,c under mild conditions. Upon examination of the scope and limitations of this reaction, it was found that the corresponding highly functionalized cyclopentane derivatives could be formed in good yields from the reaction VDCPs 1 and enol 2e or dienol 2c under identical conditions.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Reductive-Cyclization-Mediated Synthesis of Fused Polycyclic Quinolines from Baylis,Hillman Adducts of Acrylonitrile: Scope and Limitations,,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 20 2009Virender Singh Abstract The synthesis of a variety of polycyclic quinolines is described. The target molecules were obtained in two steps by an initial reductive cyclization followed by another intramolecular cyclization in the allylamines afforded from either the acetates or allyl bromides of Baylis,Hillman adducts of 2-nitrobenzaldehydes and acrylonitrile. The two steps proceeded in one-pot for those substrates in which a formyl or hydroxy group reacted with the amino group of the 2-aminoquinoline in the second intramolecular cyclization. In contrast, a basic medium was necessary for the second intramolecular cyclization reaction in substrates in which an alkoxycarbonyl group and the amino group participated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Legal Basis and Scope of the Human Rights Clauses in EC Bilateral Agreements: Any Room for Positive Interpretation?EUROPEAN LAW JOURNAL, Issue 1 2001Elena Fierro It is well known nowadays that the European Community includes a so-called human rights clause into the framework agreements that it concludes with third countries. It is also widely recognised that, in virtue of the relevant provisions of the Vienna Convention on the Law of the Treaties, such a clause grants the Community a right to suspend the agreement should human rights and/or democratic principles be breached. The question to be explored in the present paper is whether, in the light of its legal basis, the clause fulfils a mere ,negative' or ,sanctioning' function or, by contrast, there is room for the pursuit of positive measures of active promotion of human rights,that is the granting of technical and financial aid. It is argued here that the clauses present an ideal starting point for the pursuit of a comprehensive human rights policy at the EU level. Such a policy should encompass positive measures in the first place, systematic dialogue in the second, and suspension or negative measures of less extent only as ultima ratio in particularly grave cases which cannot be addressed through ordinary (dialogue and aid) routes. [source] Scope and scale inefficiencies in physician practices,HEALTH ECONOMICS, Issue 11 2004Robert Rosenman Abstract Using a national data set, this paper looks at the efficiency of physician practices, focusing on scopes of service by comparing single specialty groups and multispecialty groups. An analysis of efficiency using DEA indicates that there are scope inefficiencies from combining different types of providers into a single practice. Most of the inefficiency is due to technical rather than allocative reasons. In addition, we find that larger practices are able to capture efficiencies of scope, but incur inefficiencies of scale. Copyright © 2004 John Wiley & Sons, Ltd. [source] On the Scope of a Prins -Type Cyclization of Oxonium IonsHELVETICA CHIMICA ACTA, Issue 11 2004Georg Fráter The Prins cyclization of an aldehyde 1 with a homoallylic alcohol 2, affording tetrahydro-2H -pyrans 4via the oxonium ion 3 as central intermediate, was conceptually transferred to (alk-3-enyloxy)acrylates 6, which form a related oxonium ion 7 upon treatment with acids (Scheme,1). The scope and utility of this modification of the Prins -type cyclization of oxonium ions is discussed exemplarily by means of the syntheses of ten tetrahydro-2H -pyran and tetrahydrofuran derivatives, featuring diverse substitution patterns as well as different degrees of molecular complexity. These target structures include (±)-ethyl (2RS)-2-[(2RS,4SR,6RS)- and (2SR,4RS,6SR)-2-tetahydro-4-hydroxy-6-methylpyran-2-yl]propanoate (23), (±)-ethyl [(2RS, 3RS)-tetrahydro-3-isopropenylfuran-2-yl]acetate (32), (±)-ethyl (2Z)-3-(tetrahydro-2,2-dimethylfuran-3-yl)acrylate (37), (±)-(3aRS,6RS, 7aRS)-octahydro-7a-methylbenzofuran-6-yl formate (42), (±)-ethyl (2RS,3RS,4aRS,8SR,8aRS)-hexahydro-2,5,5,8-tetramethyl-7-oxo-2H,5H -pyrano[4,3- b]pyran-3-carboxylate (48), and (±)-ethyl (2RS,3RS,6SR)-tetrahydro-6-(2-methoxy-2-oxoethyl)-3-methyl-2H -pyran-2-carboxylate (53) (see Schemes,3 and 5,8). Besides the stereochemistry and mechanistic details of this versatile oxonium-ion cyclization, the synthesis of suitable starting materials is also described. [source] The journal Communications in Numerical Methods in Engineering with Biomedical Applications becomes the International Journal for Numerical Methods in Biomedical Engineering (IJNMBE) from 1st January 2010INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 16 2009Perumal Nithiarasu Editor Abstract Communications in Numerical Methods in Engineering, founded by Roland W. Lewis in 1985, will change its title to the ,International Journal for Numerical Methods in Biomedical Engineering' and has a revised Aims and Scope. Copyright © 2009 John Wiley & Sons, Ltd. [source] The journal Communications in Numerical Methods in Engineering with Biomedical Applications becomes the International Journal for Numerical Methods in Biomedical Engineering (IJNMBE) from 1st January 2010INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2009Perumal Nithiarasu Editor Abstract Communications in Numerical Methods in Engineering, founded by Roland W. Lewis in 1985, will change its title to the ,International Journal for Numerical Methods in Biomedical Engineering' and has a revised Aims and Scope. Copyright © 2009 John Wiley & Sons, Ltd. [source] Video-laryngoscopes in the adult airway management: a topical review of the literatureACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2010P. NIFOROPOULOU The aim of the present paper is to review the literature regarding video-laryngoscopes (Storz V-Mac and C-Mac, Glidescope, McGrath, Pentax-Airway Scope, Airtraq and Bullard) and discuss their clinical role in airway management. Video-laryngoscopes are new intubation devices, which provide an indirect view of the upper airway. In difficult airway management, they improve Cormack,Lehane grade and achieve the same or a higher intubation success rate in less time, compared with direct laryngoscopes. Despite the very good visualization of the glottis, the insertion and advancement of the endotracheal tube with video-laryngoscopes may occasionally fail. Each particular device's features may offer advantages or disadvantages, depending on the situation the anaesthesiologist has to deal with. So far, there is inconclusive evidence indicating that video-laryngoscopy should replace direct laryngoscopy in patients with normal or difficult airways. [source] Scope and Limitations of Palladium-Catalyzed Cross-Coupling Reactions with Organogold CompoundsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 8 2010A. Stephen Abstract Five different alkenylgold(I) phosphane complexes were prepared and then investigated in [1,1,-bis(diphenylphosphino)ferrocene]palladium(II) dichloride-catalyzed cross-coupling reactions with different aryl halides, heterocyclic halides, an alkenyl halide, an alkynyl halide, allylic substrates, benzyl bromide and an acid chloride. With regard to the halides, the iodides were highly reactive, bromides or chlorides gave significantly reduced yields or failed, allylic acetates failed, too. The cross-coupling partners contained a number of different functional groups, while free carboxylic acids did not deliver cross-coupling products and o,o -disubstituted arenes failed as well, a broad range of other functional groups like nitro groups, nitrile groups, ester groups, ,,,-unsaturated ester groups and lactones, aldehydes, alkoxy groups, pyridyl groups, thienyl groups, unprotected phenols and anilines, even aryl azides were tolerated. The structures of one alkenylgold(I) species and of four of the cross-coupling products were proved by crystal structure analyses. [source] Use of Commercially Available Ruthenium Fischer-Type Carbenes for Ring-Closing Metathesis Reactions: Scope and Limitations of an in situ Activation ProcedureADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Debra Abstract An evaluation of two commercially available Fischer-type ruthenium carbenes in a range of ring-closing diene and enyne metathesis reactions has been carried out. A method to activate such catalysts for ring-closing reactions is presented. [source] Exploring the Biocatalytic Scope of Alditol Oxidase from Streptomyces coelicolorADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009W. van Hellemond Abstract The substrate scope of the flavoprotein alditol oxidase (AldO) from Streptomyces coelicolor A3(2), recombinantly produced in Escherichia coli, was explored. While it has been established that AldO efficiently oxidizes alditols to D -aldoses, this study revealed that the enzyme is also active with a broad range of aliphatic and aromatic alcohols. Alcohols containing hydroxy groups at the C-1 and C-2 positions like 1,2,4-butanetriol (Km=170,mM, kcat=4.4,s,1), 1,2-pentanediol (Km=52,mM, kcat=0.85,s,1) and 1,2-hexanediol (Km=97,mM, kcat=2.0,s,1) were readily accepted by AldO. Furthermore, the enzyme was highly enantioselective for the oxidation of 1,2-diols [e.g., for 1-phenyl-1,2-ethanediol the (R)-enantiomer was preferred with an E -value of 74]. For several diols the oxidation products were determined by GC-MS and NMR. Interestingly, for all tested 1,2-diols the products were found to be the ,-hydroxy acids instead of the expected ,-hydroxy aldehydes. Incubation of (R)-1-phenyl-1,2-ethanediol with 18O-labelled water (H218O) revealed that a second enzymatic oxidation step occurs via the hydrate product intermediate. The relaxed substrate specificity, excellent enantioselectivity, and independence of coenzymes make AldO an attractive enzyme for the preparation of optically pure 1,2-diols and ,-hydroxy acids. [source] Regioselective Palladium(0)-Catalyzed Cross-Coupling Reactions and Metal-Halide Exchange Reactions of Tetrabromothiophene: Optimization, Scope and LimitationsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009ng Thanh Tůng Abstract The Suzuki reaction of tetrabromothiophene with arylboronic acids provides a regioselective approach to various 5-aryl-2,3,4-tribromothiophenes, symmetrical 2,5-diaryl-3,4-dibromothiophenes, and tetraarylthiophenes. Unsymmetrical 2,5-diaryl-3,4-dibromothiophenes are prepared by Suzuki reaction of 5-aryl-2,3,4-tribromothiophenes. Tetraarylthiophenes containing two different types of aryl groups are obtained by Suzuki reactions of 2,5-diaryl-3,4-dibromothiophenes. During the optimization of the conditions of each individual reaction, the solvent, the catalyst and the temperature play an important role. In several cases, classical conditions [use of tetrakis(triphenylphosphane)palladium(0), Pd(PPh3)4, as the catalyst] gave excellent yields. The yields of those transformations which failed or proceeded sluggishly could be significantly improved by application of a new biarylmonophosphine ligand developed by Buchwald and co-workers. Regioselective metal-halide exchange reactions of tetrabromothiophene provide a convenient approach to various 2,5-disubstituted 3,4-dibromothiophenes. 5-Alkyl-2-trimethylsilyl-3,4-dibromothiophenes could be prepared in one pot by sequential addition of trimethylchlorosilane and alkyl bromides. The reaction of tetrabromothiophene with methyl chloroformate and subsequent Suzuki reactions afforded 3,4-diaryl-2,5-bis(methoxycarbonyl)thiophenes. [source] Cyclic Enones as Substrates in the Morita,Baylis,Hillman Reaction: Surfactant Interactions, Scope and Scalability with an Emphasis on FormaldehydeADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009Brett Abstract Traditionally, cyclic enones and formalin are reactants notorious for displaying problematic behaviour (i.e., poor solubility and low yields) under Morita,Baylis,Hillman (MBH) reaction conditions. The body of research presented herein focuses on the use of surfactants in water as a solvent medium that offers a resolution to many of the issues associated with the MBH reaction. Reaction scope, scalability and small angle X-ray scattering have been studied to assist with the understanding of the reaction mechanism and industrial application. A comparison against known literature methods for reaction scale-up is also discussed. [source] Palladium(II)-Catalyzed Domino Reaction of 2-(1-Alkynyl)-2-alken-1-ones with Nucleophiles: Scope, Mechanism and Synthetic Application in the Synthesis of 3,4-Fused Bicyclic Tetrasubstituted FuransADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009Yuanjing Xiao Abstract Described herein is the development of a palladium(II)-catalyzed two- or three-component reaction of 2-(1-alkynyl)-2-alken-1-ones with nucleophiles and allylic chlorides. Various types of nucleophiles such as O- , N- , C -based nucleophiles and olefin-tethered O- , N- , C -based nucleophiles were investigated. The scope, mechanism and application of this Pd(II)-catalyzed domino reaction were studied. In these transformations, the palladium catalyst exhibits a dual role, serving simultaneously as a Lewis acid and a transition metal. Two possible reaction pathways (cross-coupling reaction vs. Heck reaction) from the same intermediate furanylpalladium species were observed. The reaction pathway is dependent on the property of the nucleophile and the length of the tethered chain as well. When olefin-tethered O -based nucleophiles were used, only the cross-coupling reaction pathway was observed, in contrast, both reaction pathways were observed when olefin-tethered C -based nucleophiles were employed. The product ratio is dependent on the length of the tethered chain. Furthermore, ring-closing metathesis (RCM) of corresponding furans with CC bonds provides an easy method for the preparation of functionalized oxygen-heterocycles , 3,4-fused bicyclic furans. It is also noteworthy that allylic chloride can be as an oxidant besides its well known function as an alkylating reagent. [source] Increasing the Scope of Palladium-Catalyzed Cyanations of Aryl ChloridesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009Thomas Schareina Abstract An improved protocol for the palladium-catalyzed cyanation of electron-rich aryl chlorides with potassium ferrocyanide {K4[Fe(CN)6]} is presented. Compared to previous procedures the substrate scope is significantly broadened. [source] Reduction of Alkyl Halides by Triethylsilane Based on a Cationic Iridium Bis(phosphinite) Pincer Catalyst: Scope, Selectivity and MechanismADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2009Jian Yang Abstract A highly efficient procedure for the reduction of a broad range of alkyl halides by triethylsilane based on a cationic iridium bis(phosphinite) pincer catalyst has been discovered and developed. This reduction chemistry is chemoselective and has unique selectivities compared with conventional radical-based processes and the aluminum trichloride/triethylsilane (AlCl3/Et3SiH) and triphenylmethyl tetrakis[pentafluorophenyl]borate/triethylsilane {[Ph3C] [B(C6F5)4]/Et3SiH} systems. Reductions use three equivalents of triethylsilane relative to the halide and can be carried out with very low catalyst loadings and in a solvent-free manner, which may provide an environmentally attractive and safe alternative to many currently practiced methods for reduction of alkyl halides. Mechanistic studies reveal a unique catalytic cycle. The cationic iridium hydride 2,6-bis[di-(tert -butyl)phosphinyloxy)phenyl(hydrido)iridium, (POCOP)IrH+ {POCOP= 2,6-[OP(t- Bu)2]2C6H3} binds and activates the silane. This complex serves as a potent silylating reagent to generate silyl halonium ions, Et3SiXR+, which are reduced by the neutral iridium dihydride to yield alkane product and regenerate the cationic (POCOP)IrH+, thus closing the catalytic cycle. All key intermediates have been identified by in situ NMR monitoring and kinetic studies have been completed. An application of this reduction system to the catalytic hydrodehalogenation of a metal chloride complex is also described. [source] Ruthenium-Indenylidene Complexes: Scope in Cross-Metathesis TransformationsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 18 2008Fabien Boeda Abstract A comparative study examining the catalytic activity of a series of five indenylidene-containing ruthenium complexes in olefin cross-metathesis reactions is presented. Results reveal the greater efficiency of precatalyst 5, highlighting the key role of the N,N, -bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) ligand for this transformation. The scope of this precatalyst was investigated and several microwave experiments were carried out allowing for catalyst loadings as low as 0.1 mol%. Overall, cross-metathesis products were isolated in moderate to excellent yields with high stereoselectivity. [source] A concept analysis of malnutrition in the elderlyJOURNAL OF ADVANCED NURSING, Issue 1 2001Cheryl Chia-Hui Chen RN MSN GNP A concept analysis of malnutrition in the elderly Purpose.,Malnutrition is a frequent and serious problem in the elderly. Today there is no doubt that malnutrition contributes significantly to morbidity and mortality in the elderly. Unfortunately, the concept of malnutrition in the elderly is poorly defined. The purpose of this paper is to clarify the meaning of malnutrition in the elderly and to develop the theoretical underpinnings, thereby facilitating communication regarding the phenomenon and enhancing research efforts. Scope, sources used.,Critical review of literature is the approach used to systematically build and develop the theoretical propositions. Conventional search engines such as Medline, PsyINFO, and CINAHL were used. The bibliography of obtained articles was also reviewed and additional articles identified. Key wards used for searching included malnutrition, geriatric nutrition, nutritional status, nutrition assessment, elderly, ageing, and weight loss. Conclusions.,The definition of malnutrition in the elderly is defined as following: faulty or inadequate nutritional status; undernourishment characterized by insufficient dietary intake, poor appetite, muscle wasting and weight loss. In the elderly, malnutrition is an ominous sign. Without intervention, it presents as a downward trajectory leading to poor health and decreased quality of life. Malnutrition in the elderly is a multidimensional concept encompassing physical and psychological elements. It is precipitated by loss, dependency, loneliness and chronic illness and potentially impacts morbidity, mortality and quality of life. [source] Modular Furanoside Diphosphite Ligands for Pd-Catalyzed Asymmetric Allylic Substitution Reactions: Scope and LimitationsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2005Montserrat Diéguez Abstract We have synthesized a library of furanoside diphosphite ligands for the Pd-catalyzed allylic substitution reactions of acyclic and cyclic allylic esters. The library has been designed to rapidly screen the ligands to uncover their important structural features and to determine the scope of diphosphite ligands in these catalytic reactions. After the systematic variation of the sugar backbone, the substituent at C-5 and the phosphite moieties, the diphosphite ligand 4c was found to be optimal in the Pd-catalyzed asymmetric allylic substitution of hindered (S1) and unhindered (S2,S5) substrates, yielding high activities [TOFs up to >3000,mol×(mol×h),1] and enantioselectivities (ees up to 99%). In addition, the screening of the library enabled us to find other suitable ligands for hindered disubstituted linear substrate S1 (ligands 1b,d, g and 4b, d, g) and for unhindered cyclic substrates S3,S5 (ligands 6c and 7c). [source] Highly Selective Biphasic Telomerization of Butadiene with Glycols: Scope and LimitationsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11 2003Arno Behr Abstract Highly selective telomerization reactions of a number of short-chain glycol nucleophiles with 1,3-butadiene have been achieved in aqueous biphasic systems employing the water-soluble catalyst system Pd(acac)2/TPPTS. For all substrates the selectivity for the obtained monotelomers 5,7 reached ,95% whereas butadiene dimers 3, octadienols 4 and ditelomers like 2 were produced only in trace amounts. The order of reactivity is ethylene glycol>>1,3-propylene glycol , glycerol>1,4-butylene glycol, which is in agreement with generally observed trends. The scope and limitations of these reactions are discussed in terms of obtained yields and achievable catalyst productivities (total turnover numbers). [source] Demographic models and the management of endangered species: a case study of the critically endangered Seychelles magpie robinJOURNAL OF APPLIED ECOLOGY, Issue 5 2003Ken Norris Summary 1Demographic models are assuming an important role in management decisions for endangered species. Elasticity analysis and scope for management analysis are two such applications. Elasticity analysis determines the vital rates that have the greatest impact on population growth. Scope for management analysis examines the effects that feasible management might have on vital rates and population growth. Both methods target management in an attempt to maximize population growth. 2The Seychelles magpie robin Copsychus sechellarum is a critically endangered island endemic, the population of which underwent significant growth in the early 1990s following the implementation of a recovery programme. We examined how the formal use of elasticity and scope for management analyses might have shaped management in the recovery programme, and assessed their effectiveness by comparison with the actual population growth achieved. 3The magpie robin population doubled from about 25 birds in 1990 to more than 50 by 1995. A simple two-stage demographic model showed that this growth was driven primarily by a significant increase in the annual survival probability of first-year birds and an increase in the birth rate. Neither the annual survival probability of adults nor the probability of a female breeding at age 1 changed significantly over time. 4Elasticity analysis showed that the annual survival probability of adults had the greatest impact on population growth. There was some scope to use management to increase survival, but because survival rates were already high (> 0·9) this had a negligible effect on population growth. Scope for management analysis showed that significant population growth could have been achieved by targeting management measures at the birth rate and survival probability of first-year birds, although predicted growth rates were lower than those achieved by the recovery programme when all management measures were in place (i.e. 1992,95). 5Synthesis and applications. We argue that scope for management analysis can provide a useful basis for management but will inevitably be limited to some extent by a lack of data, as our study shows. This means that identifying perceived ecological problems and designing management to alleviate them must be an important component of endangered species management. The corollary of this is that it will not be possible or wise to consider only management options for which there is a demonstrable ecological benefit. Given these constraints, we see little role for elasticity analysis because, when data are available, a scope for management analysis will always be of greater practical value and, when data are lacking, precautionary management demands that as many perceived ecological problems as possible are tackled. [source] | |||||||||||||||||||||||||||||||||||||