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Resolution
Kinds of Resolution Terms modified by Resolution Selected AbstractsSORTAL ANAPHORA RESOLUTION IN MEDLINE ABSTRACTSCOMPUTATIONAL INTELLIGENCE, Issue 1 2007Manabu Torii This paper reports our investigation of machine learning methods applied to anaphora resolution for biology texts, particularly paper abstracts. Our primary concern is the investigation of features and their combinations for effective anaphora resolution. In this paper, we focus on the resolution of demonstrative phrases and definite determiner phrases, the two most prevalent forms of anaphoric expressions that we find in biology research articles. Different resolution models are developed for demonstrative and definite determiner phrases. Our work shows that models may be optimized differently for each of the phrase types. Also, because a significant number of definite determiner phrases are not anaphoric, we induce a model to detect anaphoricity, i.e., a model that classifies phrases as either anaphoric or nonanaphoric. We propose several novel features that we call highlighting features, and consider their utility particularly for processing paper abstracts. The system using the highlighting features achieved accuracies of 78% and 71% for demonstrative phrases and definite determiner phrases, respectively. The use of the highlighting features reduced the error rate by about 10%. [source] 043.16 CAPACITY, DURATION and SPATIAL RESOLUTION OF WORKING MEMORY IN A FOOD-STORING and A NON-STORING BIRDEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2000R. Biegler No abstract is available for this article. [source] FAMILY DISPUTE RESOLUTION: CHARTING A COURSE FOR THE FUTUREFAMILY COURT REVIEW, Issue 3 2009Amy Holtzworth-Munroe This article summarizes ideas for future directions in the field of family dispute resolution, as discussed by legal experts, social scientists, and other participants at the Indiana University,Bloomington conference on family dispute resolution. Five major categories of future directions were discussed: (1) clarifying differing goals for work in this field; (2) recognizing, understanding, and assessing for heterogeneity among couples and families facing divorces, break ups in adult relationships, and reconfigurations of adult relationships with the children ("relationship dissolution"); (3) testing our assumptions and commonly held beliefs about relationship dissolution; (4) empirically testing the efficacy of interventions for families experiencing relationship dissolution; and (5) disseminating research findings to those on the frontline. [source] ALTERNATIVE DISPUTE RESOLUTION FOR HAGUE CONVENTION CHILD CUSTODY DISPUTES*FAMILY COURT REVIEW, Issue 2 2007Radoslaw Pawlowski This note explains that an Alternative Dispute Resolution (ADR) protocol should be adopted as part of the Hague Convention on the Civil Aspects of International Child Abduction to facilitate the amicable resolution of cross-border child custody cases. It suggests that national ADR models should be used as a guide to improve this treaty. First, this note brings to light the negative effect of cross-border litigation on children as well as the complexities and the deficiencies of this international treaty. Second, it examines mediation and arbitration systems employed in the United States, Europe, and Australia and how these can be transposed on the international scale. Third, it proposes how the ADR protocol should be drafted and implemented. A sound ADR mechanism would alleviate the unfortunate conditions of children trapped in long and destructive international child custody battles. [source] MAKING ALTERNATIVE DISPUTE RESOLUTION (ADR) LESS ALTERNATIVE: THE NEED FOR ADR AS BOTH A MANDATORY CONTINUING LEGAL EDUCATION REQUIREMENT AND A BAR EXAM TOPICFAMILY COURT REVIEW, Issue 4 2006Dori CohenArticle first published online: 11 SEP 200 Divorce proceedings have had a negative reputation due to their adversarial nature. Litigation in the family law field has exacerbated an already emotionally charged atmosphere. Alternative dispute resolution (ADR) has grown in importance over the past three decades and has helped to alleviate some of the animosity which accompanies divorce and child custody matters. Parents in particular are aided by the benefits of options such as mediation and collaborative divorce, obtaining increased control over their agreements in situations where the relationships will be continuous due to shared parenting responsibilities. However, much more could be done to increase the use of ADR in family law proceedings. Current family law practitioners could fill many roles, including mediator, advocate during mediation, collaborative negotiator, arbitrator, and counselor regarding which process to implement. Knowledge about these different roles, with their attendant skills and ethical issues, has become imperative. This Note will advocate for a mandatory continuing legal education requirement in ADR for matrimonial attorneys, as well as for the inclusion of ADR as a topic on state bar examinations. An increased knowledge of ADR will benefit divorcing parents and their children, ease an overcrowded court system, and lead to greater personal and professional satisfaction for the family law practitioner. [source] USING INCIDENT LIGHT TO MAXIMIZE RESOLUTION OF STRUCTURE ON DIATOM VALVES WITH A LIGHT MICROSCOPEJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Siver, P. A. Botany Department, Connecticut College, New London, CT 06320 Because of their abundance in a diverse array of aquatic habitats and chemical conditions, and the fact that their species-specific siliceous outer coverings remain for millennia in sediments, diatoms have become one of the most powerful organismal groups used in the reconstruction of historical environmental conditions. Although SEM is now needed to identify some species, the bulk of the identifications and data collection is still accomplished with a light microscope. In this paper I will demonstrate the use of interference reflection contrast (incident light) for the examination of diatoms that significantly improves the resolution of structural detail. Using incident light one can routinely distinguish between structures close to the theoretical limit of resolution for visible light, and about 70 nm closer together than resolvable with standard transmitted light optics. Examples of how the incident light technique can improve data collection with light microscopy will be given. Most research light microscopes could be easily and inexpensively outfitted to use this technique. [source] BEYOND NOTIONS OF DIPLOMACY AND LEGALISM: BUILDING A JUST MECHANISM FOR WTO DISPUTE RESOLUTIONAMERICAN BUSINESS LAW JOURNAL, Issue 3 2003Lawrence D. Roberts First page of article [source] LÉVI-STRAUSS AND THE POLITICAL: THE ELEMENTARY STRUCTURES OF KINSHIP AND THE RESOLUTION OF RELATIONS BETWEEN INDIGENOUS PEOPLES AND SETTLER STATESTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 3 2005Michael Asch This article addresses the contribution of Lévi-Strauss's The elementary structures of kinship to resolving political relations between indigenous peoples and the settler states. To this end, it explores his discussion of the origins of society within the context of Enlightenment-inspired political thought and concludes that he provides a unique, counter-hegemonic alternative to conventional narratives. It then shows how this argument thwarts the presumption in Canadian jurisprudence that indigenous peoples were automatically incorporated into the state through European settlement, and fosters an understanding that a relationship based on the concept of ,Treaty' as understood in indigenous political thought promotes a political relationship that affirms the integrity of all parties. [source] THE EVOLUTION OF FILIAL CANNIBALISM AND FEMALE MATE CHOICE STRATEGIES AS RESOLUTIONS TO SEXUAL CONFLICT IN FISHESEVOLUTION, Issue 2 2000Kai Lindström Abstract., Filial cannibalism (the consumption of one's own viable offspring) is common among fish with paternal care. In this study, I use a computer simulation to study simultaneous evolution of male filial cannibalism and female mate choice. Under certain conditions, selection on parental males favors filial cannibalism. When filial cannibalism increases a male's probability to raise the current brood successfully, filial cannibalism also benefits the female. However, when egg eating is a male investment into future reproduction, a conflict between female and male interests emerges. Here I investigate how female discrimination against filial cannibals affects evolution of filial cannibalism and how different female choice criteria perform against filial cannibalism. The introduction of discriminating females makes the fixation of filial cannibalism less likely. I introduced three different female choice criteria: (1) females who could discern a male's genotype, that is, whether the male was going to eat eggs as an investment in future reproductive events; (2) energy-choosing females that preferred to mate with males who had enough energy reserves to live through the current brood cycle without consuming eggs; and (3) females that preferred to mate with already mated males, that is, males with eggs in their nest. Genotype choice never coexisted with filial cannibals at fixation and filial cannibals were unable to invade a population with genotype-choosing females. Energy choice was successful only when males had high energy reserves and were less dependent on filial cannibalism as an alternative energy source. The egg choosers frequently coexisted with the cannibals at fixation. When the female strategies were entered simultaneously, the most frequent outcome for low mate sampling costs was that both the cannibals and the egg choice was fixed and all other strategies went extinct. These results suggest that sexual conflicts may not always evolve toward a resolution of the conflict, but sometimes the stable state retains the conflict. In the present case, this was because the egg-preference strategy had a higher fitness than the other female strategies. The outcome of this simulation is similar to empirical findings. In fish with paternal care, male filial cannibalism and female preference for mates with eggs commonly co-occur. [source] A modified CRISIS-HSQC for band-selective IMPRESSMAGNETIC RESONANCE IN CHEMISTRY, Issue 2 2005Scott A. Bradley Abstract CRISIS (Compensation of Refocusing Inefficiency with Synchronized Inversion Sweep) is a powerful technique for obtaining multiplicity-edited HSQC spectra without compromising sensitivity. However, the stringent requirement for the duration of the CRISIS waveforms makes them unsuitable for other functions, such as band selection or IMPRESS (IMProved REsolution using Symmetrically Shifted pulses). We report here a modified CRISIS-gHSQC pulse sequence employing time-reversed 13C ,/2 EBURP-2 pulses. This IC-bs-gHSQC (IMPRESS-CRISIS-bs-gHSQC) sequence was found to be equally useful for acquiring multiplicity-edited, band-selective spectra individually or in tandem with IMPRESS. Remarkably, the latter provides multiple spectra in significantly less time and is the preferred approach when several crowded regions need to be assigned unambiguously. The use of adiabatic sweeps and the CRISIS pulses enable IC-bs-gHSQC to give better sensitivity than the original IMPRESS sequence for band-selective spectra. Copyright © 2005 John Wiley & Sons, Ltd. [source] Reinterpretable Imager: Towards Variable Post-Capture Space, Angle and Time Resolution in PhotographyCOMPUTER GRAPHICS FORUM, Issue 2 2010Amit Agrawal Abstract We describe a novel multiplexing approach to achieve tradeoffs in space, angle and time resolution in photography. We explore the problem of mapping useful subsets of time-varying 4D lightfields in a single snapshot. Our design is based on using a dynamic mask in the aperture and a static mask close to the sensor. The key idea is to exploit scene-specific redundancy along spatial, angular and temporal dimensions and to provide a programmable or variable resolution tradeoff among these dimensions. This allows a user to reinterpret the single captured photo as either a high spatial resolution image, a refocusable image stack or a video for different parts of the scene in post-processing. A lightfield camera or a video camera forces a-priori choice in space-angle-time resolution. We demonstrate a single prototype which provides flexible post-capture abilities not possible using either a single-shot lightfield camera or a multi-frame video camera. We show several novel results including digital refocusing on objects moving in depth and capturing multiple facial expressions in a single photo. [source] Variable Resolution 4- k Meshes: Concepts and ApplicationsCOMPUTER GRAPHICS FORUM, Issue 4 2000Luiz Velho In this paper we introduce variable resolution 4-k meshes, a powerful structure for the representation of geometric objects at multiple levels of detail. It combines most properties of other related descriptions with several advantages, such as more flexibility and greater expressive power. The main unique feature of the 4-k mesh structure lies in its variable resolution capability, which is crucial for adaptive computation. We also give an overview of the different methods for constructing the 4-k mesh representation, as well as the basic algorithms necessary to incorporate it in modeling and graphics applications. [source] Peer mediation training and program implementation in elementary schools: Research resultsCONFLICT RESOLUTION QUARTERLY, Issue 2 2002Kathy Bickmore This research examines the implementation and effects of a peer mediation program in twenty-eight urban elementary schools. The Center for Conflict Resolution, a program of the Cleveland, Ohio, public schools, provided intensive training and follow-up support for teams of peer mediators and adult advisers at each school. Trainers were youths from the same community. Qualitative and quantitative evidence indicate that this program significantly improved the average eight- to eleven-year-old students understanding of and inclination to use nonviolent conflict resolution and his or her capacity to achieve in school. The study outlines the specific commitments from administrators and other staff members that were required to develop and implement equitable, effective, and sustainable programs. [source] Rapid Onset and Resolution of Cardiogenic Shock in a Patient With PheochromocytomaCONGESTIVE HEART FAILURE, Issue 3 2009Jeffrey A. Shih MD First page of article [source] Student Conflict Resolution, Power "Sharing" in Schools, and Citizenship EducationCURRICULUM INQUIRY, Issue 2 2001Kathy Bickmore One goal of elementary education is to help children develop the skills, knowledge, and values associated with citizenship. However, there is little consensus about what these goals really mean: various schools, and various programs within any school, may promote different notions of "good citizenship." Peer conflict mediation, like service learning, creates active roles for young people to help them develop capacities for democratic citizenship (such as critical reasoning and shared decision making). This study examines the notions of citizenship embodied in the contrasting ways one peer mediation model was implemented in six different elementary schools in the same urban school district. This program was designed to foster leadership among diverse young people, to develop students' capacities to be responsible citizens by giving them tangible responsibility, specifically the power to initiate and carry out peer conflict management activities. In practice, as the programs developed, some schools did not share power with any of their student mediators, and other schools shared power only with the kinds of children already seen as "good" students. All of the programs emphasized the development of nonviolent community norms,a necessary but not sufficient condition for democracy. A few programs began to engage students in critical reasoning and/or in taking the initiative in influencing the management of problems at their schools, thus broadening the space for democratic learning. These case studies help to clarify what our visions of citizenship (education) may look and sound like in actual practice so that we can deliberate about the choices thus highlighted. [source] Near-infrared dyes for six-color immunophenotyping by laser scanning cytometryCYTOMETRY, Issue 3 2002Andreas O.H. Gerstner Abstract Background To adequately analyze the complexity of the immune system and reduce the required sample volume for immunophenotyping in general, more measurable colors for the discrimination of leukocyte subsets are necessary. Immunophenotyping by the laser scanning cytometer (LSC), a slide-based cytometric technology, combines cell detection based on multiple colors with their subsequent visualization without the need for physical cell sorting. In the present study, the filter setting of the LSC was adapted for the measurement of the far-red emitting dye cyanine 7 (Cy7), thereby increasing the number of measurable commercially available fluorochromes. Methods The optical filters of the LSC were replaced,photomultiplier (PMT) 3/allophycocyanin (APC): 740-nm dichroic long pass, and 670-/55-nm bandpass; PMT 4/Cy7: 810-/90-nm bandpass. Peripheral blood leukocytes were stained directly by fluorochrome-labeled antibodies or by indirect staining. The tandem dyes of Cy7 (phycoerythrin [PE]-Cy7, APC-Cy7) and the fluorochromes fluorescein isothiocyanate (FITC), PE, PE-Cy5, and APC were tested alone and in different combinations. Results With the new filter combination and tandem fluorochromes, Cy7 was measurable at 488-nm (argon laser) or 633-nm (helium-neon laser) excitation. Resolution was in the range of FITC for PE-Cy7 but approximately 30% lower for APC-Cy7; spillover into the respective donor fluorochrome channel for both tandem dyes was prominent. A six-color panel for leukocyte subtyping was designed. Conclusions With this adaptation, it is possible to measure the tandem conjugates PE-Cy7 and APC-Cy7. This new setup opens the way for six-color immunophenotyping by LSC. Cytometry 48:115,123, 2002. © 2002 Wiley-Liss, Inc. [source] Clear Cell Acanthoma Successfully Treated with a Carbon Dioxide LaserDERMATOLOGIC SURGERY, Issue 10 2005Ching-Chi Chi MD Background. The treatment of choice for clear cell acanthoma (CCA) is excision. Resolution after cryotherapy has also been reported but requires three to four courses of treatment. Objective. To demonstrate three CCA lesions in two patients successfully treated with a carbon dioxide (CO2) laser. Methods. Under local anesthesia, these lesions were vaporized by using a CO2 laser in the Silktouch mode with a spot size of 5 mm and a fluence of 20 J/cm2. Two to six passes, as needed, were delivered until the tumor was completely removed. Results. Pain was minimal or nonexistent during and after the operation. No postoperative edema was noted. The wounds healed satisfactorily without scarring. No sign of recurrence was found following operation. Conclusion. The CO2 laser has the advantages of requiring only one course, precise tumor removal, a relatively bloodless surgical field, a short operation time, and less or no postoperative pain and edema. Postoperative wound care is convenient and easy with hydrocolloid and alginate dressings. The patient's quality of life is less adversely affected. The CO2 laser may be appropriate for multiple CCAs, giant CCA, CCA overlying or near joints, CCA refractory to cryotherapy, patients on anticoagulants, and those who cannot tolerate pain from cryotherapy, especially children and the elderly. [source] Orthopaedic issues in the musculoskeletal care of adults with cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2009HELEN M HORSTMANN MD Aims, Orthopaedic care of adults with cerebral palsy (CP) has not been well documented in orthopaedic literature. This paper focuses on some of the common problems which present themselves when adults with CP seek orthopaedic intervention. In particular, we review the most common orthopaedic issues which present to the Penn Neuro-Orthopaedics Program. Method, A formal review of consecutive surgeries performed by the senior author on adults with CP was previously conducted. This paper focuses on the health delivery care for the adult with orthopaedic problems related to cerebral palsy. Ninety-two percent of these patients required lower extremity surgery. Forty percent had procedures performed on the upper extremities. Results, The majority of problems seen in the Penn Neuro-Orthopaedics Program are associated with the residuals of childhood issues, particularly deformities associated with contractures. Patients are also referred for treatment of acquired musculoskeletal problems such as degenerative arthritis of the hip or knee. A combination of problems contribute most frequently to foot deformities and pain with weight-bearing, shoewear or both, most often due to equinovarus. The surgical correction of this is most often facilitated through a split anterior tibial tendon transfer. Posterior tibial transfers are rarely indicated. Residual equinus deformities contribute to a pes planus deformity. The split anterior tibial tendon transfer is usually combined with gastrocnemius-soleus recession and plantar release. Transfer of the flexor digitorum longus to the os calcis is done to augment the plantar flexor power. Rigid pes planus deformity is treated with a triple arthrodesis. Resolution of deformity allows for a good base for standing, improved ability to tolerate shoewear, and/or braces. Other recurrent or unresolved issues involve hip and knee contractures. Issues of lever arm dysfunction create problems with mechanical inefficiency. Upper extremity intervention is principally to correct contractures. Internal rotation and adductor tightness at the shoulder makes for difficult underarm hygiene and predispose a patient to a spiral fracture of the humerus. A tight flexor, pronation pattern is frequently noted through the elbow and forearm with further flexion contractures through the wrist and fingers. Lengthenings are more frequently performed than tendon transfers in the upper extremity. Arthrodesis of the wrist or on rare occasions of the metacarpal-phalangeal joints supplement the lengthenings when needed. Conclusions, The Penn Neuro-Orthopaedics Program has successfully treated adults with both residual and acquired musculoskeletal deformities. These deformities become more critical when combined with degenerative changes, a relative increase in body mass, fatigue, and weakness associated with the aging process. [source] Defining and measuring braiding intensityEARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2008Roey Egozi Abstract Geomorphological studies of braided rivers still lack a consistent measurement of the complexity of the braided pattern. Several simple indices have been proposed and two (channel count and total sinuosity) are the most commonly applied. For none of these indices has there been an assessment of the sampling requirements and there has been no systematic study of the equivalence of the indices to each other and their sensitivity to river stage. Resolution of these issues is essential for progress in studies of braided morphology and dynamics at the scale of the channel network. A series of experiments was run using small-scale physical models of braided rivers in a 3 m , 20 m flume. Sampling criteria for braid indices and their comparability were assessed using constant-discharge experiments. Sample hydrographs were run to assess the effect of flow variability. Reach lengths of at least 10 times the average wetted width are needed to measure braid indices with precision of the order of 20% of the mean. Inherent variability in channel pattern makes it difficult to achieve greater precision. Channel count indices need a minimum of 10 cross-sections spaced no further apart than the average wetted width of the river. Several of the braid indices, including total sinuosity, give very similar numerical values but they differ substantially from channel-count index values. Consequently, functional relationships between channel pattern and, for example, discharge, are sensitive to the choice of braid index. Braid indices are sensitive to river stage and the highest values typically occur below peak flows of a diurnal (melt-water) hydrograph in pro-glacial rivers. There is no general relationship with stage that would allow data from rivers at different relative stage to be compared. At present, channel count indices give the best combination of rapid measurement, precision, and range of sources from which measurements can be reliably made. They can also be related directly to bar theory for braided pattern development. Copyright © 2008 John Wiley & Sons, Ltd. [source] Resolution of a Primary Intracardiac LymphomaECHOCARDIOGRAPHY, Issue 6 2003Suraj Maraj No abstract is available for this article. [source] Fabrication of Active Horseradish Peroxidase Micropatterns with a High Resolution by Scanning Electrochemical MicroscopyELECTROANALYSIS, Issue 16 2007Xuemei Li Abstract We used a new reactive species OH, to fabricate active horseradish peroxidase (HRP) micropatterns with a high resolution by scanning electrochemical microscopy (SECM) coupled with a carbon fiber disk electrode as the SECM tip. In this method, except for active HRP micropatterns predesigned other regions on a HRP-immobilized substrate were deactivated by OH, generated at the tip held at ,1.7,V in 1.0,mol/L KCl containing 2.0×10,3 mol/L benzoquinone (BQ) (pH,8.0). The feedback mode of SECM with a tip potential of ,0.2,V was used to characterize the active HRP micropatterns in 1.0,mol/L KCl containing 2.0×10,3 mol/L BQ and 2.0×10,3 mol/L H2O2. [source] Enhanced Resolution of Copper and Bismuth by Addition of Gallium in Anodic Stripping Voltammetry with the Bismuth Film ElectrodeELECTROANALYSIS, Issue 24 2006Chad Prior Abstract This paper presents the enhanced analysis of copper on a bismuth electrode upon addition of gallium(III). The presence of gallium alleviates the problems of overlapping stripping signals usually observed between copper and bismuth when using the Bismuth Film Electrode. In addition, it has been found that the presence of gallium improves the reproducibility of the bismuth stripping signal. Simultaneous deposition of copper and bismuth at ,1500,mV for 2,minutes in a supporting electrolyte composed of 0.1,M pH,4.75 acetate buffer with 250,,g L,1 gallium yields well resolved copper and bismuth signals when analyzed with square-wave anodic stripping voltammetry. Simultaneous analysis of copper and lead yielded linear calibration plots in the range 10 to 100,,g L,1 with regression coefficients of 0.997 and 0.994 respectively. The theoretical detection limit for copper was calculated to be 4.98,,g L,1 utilizing a 2,minutes deposition time. The relative standard deviation for a copper concentration of 50,,g L,1 was 1.6% (n=10). [source] Electrophoresis on a microfluidic chip for analysis of fluorescence-labeled human rhinovirusELECTROPHORESIS, Issue 24 2007Viliam Kolivo Abstract We report the analysis of human rhinovirus serotype 2 (HRV2) on a commercially available lab-on-a-chip instrument. Due to lack of sufficient native fluorescence, the proteinaceous capsid of HRV2 was labeled with Cy5 for detection by the red laser (,ex 630,nm) implemented in the instrument. On the microdevice, electrophoresis of the labeled virus was possible in a BGE without stabilizing detergents, which is in contrast to conventional CE; moreover, analysis times were drastically shortened to the few 10,s range. Resolution of the sample constituents (virions, a contaminant present in all virus preparations, and excess dye) was improved upon adaptation of the separation conditions, mainly by adjusting the SDS concentration of the BGE. Purity of fractions from size-exclusion chromatography after labeling of virus was assessed, and affinity complex formation of the labeled virus with various recombinant very-low-density lipoprotein receptor derivatives differing in the number of concatenated V3 ligand binding repeats was monitored. Virus analysis on microchip devices is of particular interest for experiments with infectious material because of easy containment and disposal of samples. Thus, the employment of microchip devices in routine analysis of viruses appears to be exceptionally attractive. [source] Use of chiral zwitterionic surfactants for enantiomeric resolutions by capillary electrophoresisELECTROPHORESIS, Issue 15 2003Mark R. Hadley Abstract The enantiomeric resolution of 1,1'-binaphthyl-2,2'-diamine and Tröger's base was investigated using the commercially available zwitterionic surfactants 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulphonate (CHAPS) and 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulphonate (CHAPSO). Resolution of the weakly basic chiral probes was achieved using varying concentrations of surfactant, above their critical micellar concentrations, in a phosphate buffer (pH 2.5; 100 mM) to ensure ionisation of the analytes. Both CHAPS and CHAPSO were employed in the absence of additional coselectors or surfactants as sole micellar-forming agents. The addition of organic modifiers, methanol and acetonitrile (ACN), to the background electrolyte (BGE) was found to have a detrimental effect on enantioselectivity presumably by alteration of the phase polarity. [source] The diabetes epidemic , the case for a UN Resolution on diabetesEUROPEAN DIABETES NURSING, Issue 1 2006Professor Martin Silink [source] P-Chirogenic Benzo-Fused Phenoxaphosphane: Synthesis, Resolution and Study of the Stereochemical Properties of the Corresponding Palladium ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2008Franco Doro Abstract The synthesis and resolution of chiral phenoxaphosphane 3, with the stereogenic center at the phosphorus atom, is described. Compound 3 has been synthesized following a well-known procedure for trapping a phosphorus atom within a six-membered ring. The resolution of the racemic mixture of 3 was achieved through separation of its diastereomeric palladacycle derivatives 7a,b and 9a,b. The absolute configuration of enantiopure phosphanes 3a,b was assigned unequivocally by means of X-ray crystal structure determination for complex 9a and by combination of NOE(1H,1H)/COSY(1H,1H) spectroscopy and DFT calculations for complexes 7a,b, which in both cases led to identical results. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Syntheses, Spectroscopic Studies, and Crystal Structures of Chiral [Rh(aminocarboxylato)(,4 -cod)] and Chiral [Rh(amino alcohol)(,4 -cod)](acetate) Complexes with an Example of a Spontaneous Resolution of a Racemic Mixture into Homochiral Helix-EnantiomersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006Mohammed Enamullah Abstract The dimeric complex acetato(,4 -cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(,4 -cod)]2 (cod = cycloocta-1,5-diene), reacts with amino acids [HAA = L -alanine, (S)-2-amino-2-phenylacetic acid (L -phenylglycine), N -methylglycine, and N -phenylglycine] and with the amino alcohol (S)-2-amino-2-phenylethanol to afford the aminocarboxylato(,4 -cycloocta-1,5-diene)rhodium(I) complexes [Rh(AA)(,4 -cod)] (AA = deprotonated amino acid = aminocarboxylato ligand) and [(S)-2-amino-2-phenylethanol](,4 -cycloocta-1,5-diene)rhodium(I) acetate, [Rh{(S)-HOCH2,CH(Ph)-NH2}(,4 -cod)](O2CMe) (V). The complexes are characterized by IR, UV/Vis, 1H/13C NMR and mass spectroscopy. The achiral N -phenylglycine ligand gives a chiral N -phenylglycinato complex [Rh(O2C,CH2,NHPh)(,4 -cod)] (IV) with the amine nitrogen atom becoming the stereogenic center upon metal coordination. Complex IV crystallizes in the tetragonal, chiral space group P43 and the crystal structure reveals twofold spontaneous resolution of a racemic mixture into homochiral helix-enantiomers. The investigated crystal contained only one type of helix, namely (left-handed or M- ) 43 -helical chains. This is traced first to an intermolecular N,H···O hydrogen bonding from the stereogenic amino group to a neighboring unligated carboxyl oxygen atom that connects only molecules of the same (R)-configuration into (left-handed or M- ) 43 -helical chains. This intrachain homochirality is supplemented, secondly, by the interlocking of adjacent chains with their corrugated van der Waals surface to allow for an interchain transmission of the sense of helicity, building the single crystal from the same homochiral helix-enantiomer. The enantiomeric amino alcohol complex V crystallizes in the monoclinic, noncentrosymmetric (Sohncke) space group P21. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Kinetic Resolution of Racemic Secondary Alcohols Mediated by N -Methylimidazole in the Presence of Optically Active Acyl ChloridesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2010Loďc Leclercq Abstract N -Methylimidazole was used to promote the acylation of secondary racemic alcohols and to carry out their kinetic resolution through intermediate chiral acyl imidazolium chlorides. The kinetic resolution could be turned into a catalytic process in the presence of a catalytic amount of N -methylimidazole. [source] Dynamic Enzymatic Kinetic Resolution of Methyl 2,3-Dihydro-1H -indene-1-carboxylateEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 35 2009Jörg Pietruszka Abstract A new reaction setup for kinetic enzymatic resolution was established and is demonstrated for the case of the hydrolase-catalysed conversion of methyl 2,3-dihydro-1H -indene-1-carboxylate (1) in conjunction with a base-catalysed racemisation. The system allows controlled racemisation, resulting in efficient dynamic kinetic resolution (DKR) of the title compound. Short reaction times and high enantioselectivities were obtained with CAL-B and TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene). Compound (R)- 1 (ee 95,%) served as a starting material in a domino reaction that led to the biaryl indanyl ketone (R)- 8, a lead compound for novel inhibitors of peptidyl-prolyl- cis/trans -isomerases, in 94,% ee. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Tetra- tert -butyltrioxabicyclo[3.3.1]nonadienedicarboxylic Acid: Optical Resolution, Absolute Configuration and Application in Chiral DiscriminationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2008Jennifer Kremsner Abstract The enantiopure bridged bis-dioxine 4, a dissymmetric dicarboxylic acid exhibiting axial chirality, can easily be synthesized and serve as host for separating and/or transporting chiral guest molecules. Racemic 4 gives with (R)- and (S)-1-phenylethylamine the corresponding pure diastereomeric salts 7 and 8. The absolut configuration of the diacid 4 in the diastereomeric salt 7 containing (R)-1-phenylethylamine was confirmed to be R by X-ray crystal structure analysis, which also confirmed its concave nature. Release of the acid-sensitive pure enantiomers (R)- 4 as well as (S)- 4 was achieved conveniently by use of dry flash-chromatography on silica. The CD spectrum shows a positive Cotton effect of the (S)-enantiomer at 206 nm. The enantiomeric purity was proved by 1H NMR discrimination of the diastereomeric salts with (R,R)-1,2-bis(4-methoxyphenyl)ethane-1,2-diamine as the base. The dicarboxylic acid (R)- 4 can be used as chiral auxiliary as demonstrated by the difficult resolution of racemicN,N,-di- tert -butyl-1,2-bis(4-methoxyphenyl)ethane-1,2-diamine 9.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] | ||||||||||||||||||||||||||||||||||||||||||||||