618 research outputs found
Proposal : Organokatalysatoren fĂŒr die fluorige biphasische Katalyse ; Möglichkeiten der homogenen Katalyse mit anschlieĂendem KatalysatorâRecycling
Ăbertragung des Konzeptes der fluorigen biphasischen Systeme bzw. Ăbergangsmetallkatalyse auf die fluorige biphasische Organokatalyse. Entwicklung neuer Organokatalysatoren fĂŒr dieses neuartige Katalysekonzept auf der Basis bereits bekannter Taddol, Thioharnstoff und Binolphosphat-Katalysatoren. Synthese der vorgestellten fluorigen Organokatalysatoren. Einsatzgebiete, Katalysatorrecycling.A new Concept in Organocatalysis is presented. Fluorous biphasic Organocatalysis, derived from fluorous biphasic systems, is based on commonly used organocatalysts, such as taddol, thiourea, binol-phosphate.synthesis and design of catalysts as well as potential applications and recycling methods are presented
Recommended from our members
The Utilization of Nutrition Services in Family-Based Treatment by Members of the Society for Adolescent Health and Medicine in the care of Adolescents with Anorexia Nervosa
Family-Based Treatment (FBT), is the treatment of choice for adolescents with anorexia nervosa (AN). Much research supports its success, and yet little is known about its use by adolescent health care providers and their use of nutrition providers. Objective: This study aimed to identify the use of FBT and its treatment manual in the treatment of adolescent patients with AN by members of the Society for Adolescent Health and Medicine (SAHM), as well as the utilization of a dietitian in the treatment process. Method: In total, 72 SAHM members completed an online survey. Results: Overall, 84% of responding SAHM practitioners (81% in the USA) recommended FBT for the treatment of patients with AN --- with 54% of providers feeling that they had the necessary support and resources to implement FBT in their area of practice. Only 9% of those who practice FBT stated that the follow the treatment manual exactly as written, with 48% following just the principles of the manual. Of those who utilized FBT, 97% (98% in the USA), stated that a dietitian was used as part of the treatment team. Discussion: Given the need for consistency among practitioners, further research is needed to assess and define the role of the dietitian in FBT
Spacetime Encodings II - Pictures of Integrability
I visually explore the features of geodesic orbits in arbitrary stationary
axisymmetric vacuum (SAV) spacetimes that are constructed from a complex Ernst
potential. Some of the geometric features of integrable and chaotic orbits are
highlighted. The geodesic problem for these SAV spacetimes is rewritten as a
two degree of freedom problem and the connection between current ideas in
dynamical systems and the study of two manifolds sought. The relationship
between the Hamilton-Jacobi equations, canonical transformations, constants of
motion and Killing tensors are commented on. Wherever possible I illustrate the
concepts by means of examples from general relativity. This investigation is
designed to build the readers' intuition about how integrability arises, and to
summarize some of the known facts about two degree of freedom systems. Evidence
is given, in the form of orbit-crossing structure, that geodesics in SAV
spacetimes might admit, a fourth constant of motion that is quartic in momentum
(by contrast with Kerr spacetime, where Carter's fourth constant is quadratic).Comment: 11 pages, 10 figure
Fatty-acid amide hydrolase polymorphisms and post-traumatic stress disorder after penetrating brain injury
The past few years have seen an increase in the clinical awareness of post-traumatic stress disorder (PTSD), one of the most disabling and least understood behavioral disorders. Although the biological bases of PTSD are poorly understood, fatty-acid amide hydrolase (FAAH) activity has been linked with arousability and aversive-memories extinction, that is, two key features of PTSD. In this study, we investigated the association between the FAAH genetic polymorphisms and PTSD development and maintenance. We assessed PTSD frequency in a group of male Vietnam war veterans who suffered combat-related penetrating traumatic brain injury, that is, a relatively homogeneous population regarding the nature of the events that led to PTSD. We showed that rs2295633, a single-nucleotide polymorphism of FAAH, was significantly associated with PTSD diagnosis in subjects without lesions in the ventromedial prefrontal cortex. Moreover, the presence of the C allele was associated with more severe re-experiencing of trauma and more negative reported childhood experiences. In conclusion, our data suggest that FAAH has an important role in PTSD through modulation of aversive memories and point to both a novel therapeutic target and a possible risk marker for this condition
Damage to the prefrontal cortex increases utilitarian moral judgements
The psychological and neurobiological processes underlying moral judgement have been the focus of many recent empirical studies1â11. Of central interest is whether emotions play a causal role in moral judgement, and, in parallel, how emotion-related areas of the brain contribute to moral judgement. Here we show that six patients with focal bilateral damage to the ventromedial prefrontal cortex (VMPC), a brain region necessary for the normal generation of emotions and, in particular, social emotions12â14, produce an abnor- mally âutilitarianâ pattern of judgements on moral dilemmas that pit compelling considerations of aggregate welfare against highly emotionally aversive behaviours (for example, having to sacrifice one personâs life to save a number of other lives)7,8. In contrast, the VMPC patientsâ judgements were normal in other classes of moral dilemmas. These findings indicate that, for a selective set of moral dilemmas, the VMPC is critical for normal judgements of right and wrong. The findings support a necessary role for emotion in the generation of those judgements
Nondegenerate 3D complex Euclidean superintegrable systems and algebraic varieties
A classical (or quantum) second order superintegrable system is an integrable
n-dimensional Hamiltonian system with potential that admits 2n-1 functionally
independent second order constants of the motion polynomial in the momenta, the
maximum possible. Such systems have remarkable properties: multi-integrability
and multi-separability, an algebra of higher order symmetries whose
representation theory yields spectral information about the Schroedinger
operator, deep connections with special functions and with QES systems. Here we
announce a complete classification of nondegenerate (i.e., 4-parameter)
potentials for complex Euclidean 3-space. We characterize the possible
superintegrable systems as points on an algebraic variety in 10 variables
subject to six quadratic polynomial constraints. The Euclidean group acts on
the variety such that two points determine the same superintegrable system if
and only if they lie on the same leaf of the foliation. There are exactly 10
nondegenerate potentials.Comment: 35 page
Geometric discretization of the Koenigs nets
We introduce the Koenigs lattice, which is a new integrable reduction of the
quadrilateral lattice (discrete conjugate net) and provides natural integrable
discrete analogue of the Koenigs net. We construct the Darboux-type
transformations of the Koenigs lattice and we show permutability of
superpositions of such transformations, thus proving integrability of the
Koenigs lattice. We also investigate the geometry of the discrete Koenigs
transformation. In particular we characterize the Koenigs transformation in
terms of an involution determined by a congruence conjugate to the lattice.Comment: 17 pages, 2 figures; some spelling and typing errors correcte
Manganese as a Probe of Fungal Degradation of Wood
Transition state metals, such as manganese (Mn) and iron (Fe), have been reported to be involved in fungal degradation of wood (Ellis, 1959; Shortl
Stable isotopes reveal trophic relationships and diet of consumers in temperate kelp forest and coral reef ecosystems
We explored the use of stable nitrogen (N) isotope analysis to assess trophic position of consumers in two marine ecosystems: the kelp forests of southern California and a coral atoll in the tropical Pacific. The delta N-15 values of consumers in both ecosystems increased from known herbivores (invertebrates and fish) to higher-level consumers (predatory invertebrates and fish). In the absence of data on trophic enrichment in N-15 for our study species, we used the oft-cited value of +3.4 parts per thousand increase in delta N-15 value per trophic level and estimates of the delta N-15 producer baseline value to estimate trophic position. The trophic position of consumers computed using N isotopes compared favorably to published observations of diet. Nitrogen isotope analysis revealed that some of our higher-level fish consumers from rocky reefs (i.e., some rockfish) were feeding largely on invertebrates rather than on fish, as is often assumed. Our analysis also suggests that higher-level consumers on coral reefs may consume more herbivorous prey (i.e., both fishes and invertebrates) than previously reported. Our data support the use of nitrogen isotope values to assess trophic position and, thus, their utility as one metric with which to explore the effects of short- and longer-term natural and human-induced changes on kelp forest and coral reef food webs
Mathematically Gifted Adolescents Have Deficiencies in Social Valuation and Mentalization
Many mathematically gifted adolescents are characterized as being indolent, underachieving and unsuccessful despite their high cognitive ability. This is often due to difficulties with social and emotional development. However, research on social and emotional interactions in gifted adolescents has been limited. The purpose of this study was to observe differences in complex social strategic behaviors between gifted and average adolescents of the same age using the repeated Ultimatum Game. Twenty-two gifted adolescents and 24 average adolescents participated in the Ultimatum Game. Two adolescents participate in the game, one as a proposer and the other as a responder. Because of its simplicity, the Ultimatum Game is an apt tool for investigating complex human emotional and cognitive decision-making in an empirical setting. We observed strategic but socially impaired offers from gifted proposers and lower acceptance rates from gifted responders, resulting in lower total earnings in the Ultimatum Game. Thus, our results indicate that mathematically gifted adolescents have deficiencies in social valuation and mentalization
- âŠ