4,424 research outputs found
Enhancement and suppression effects resulting from information structuring in sentences
Information structuring through the use of cleft sentences increases the processing efficiency of references to elements within the scope of focus. Furthermore, there is evidence that putting certain types of emphasis on individual words not only enhances their subsequent processing, but also protects these words from becoming suppressed in the wake of subsequent information, suggesting mechanisms of enhancement and suppression. In Experiment 1, we showed that clefted constructions facilitate the integration of subsequent sentences that make reference to elements within the scope of focus, and that they decrease the efficiency with reference to elements outside of the scope of focus. In Experiment 2, using an auditory text-change-detection paradigm, we showed that focus has similar effects on the strength of memory representations. These results add to the evidence for enhancement and suppression as mechanisms of sentence processing and clarify that the effects occur within sentences having a marked focus structure
Laboratory and observational study of the interrelation of the carbonaceous component of interstellar dust and solar system materials
By studying the chemical and isotopic composition of interstellar ice and dust, one gains insight into the composition and chemical evolution of the solid bodies in the solar nebula and the nature of the material subsequently brought into the inner part of the solar system by comets and meteorites. It is now possible to spectroscopically probe the composition of interstellar ice and dust in the mid-infrared, the spectral range which is most diagnostic of fundamental molecular vibrations. We can compare these spectra of various astronomical objects (including the diffuse and dense interstellar medium, comets, and the icy outer planets and their satellites) with the spectra of analogs we produce in the laboratory under conditions which mimic those in these different objects. In this way one can determine the composition and abundances of the major constituents of the various ices and place general constraints on the types of organics coating the grains in the diffuse interstellar medium. In particular we have shown the ices in the dense clouds contain H2O, CH3OH, CO, perhaps some NH3 and H2CO, we well as nitriles and ketones or esters. Furthermore, by studying the photochemistry of these ice analogs in the laboratory, one gains insight into the chemistry which takes place in interstellar/precometary ices. Chemical and spectroscopic studies of photolyzed analogs (including deuterated species) are now underway. The results of some of these studies will be presented and implications for the evolution of the biogenic elements in interstellar dust and comets will be discussed
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Alignment and Defect Structures in Oriented Phosphatidylcholine Multilayers
The alignment of dilauryl-, dimyristoyl-, and dipalmitoylphosphatidylcholine at various water concentrations into large oriented monodomain multilayers by annealing at elevated temperatures (Powers and Clark, 1975, Proc. Natl. Acad. Sci. U.S.A. 72:840; Powers and Pershan. 1977. Biophys. J. 20:137) is accompanied by the formation and subsequent dissolution of various defect structures. Some of these defects appear similar to those observed in thermotropic and other lyotropic liquid crystals, reflecting the lamellar structure of these materials. The formation and evolution of defects during the alignment of the lipids into the defect-free, monodomain, multilamellar geometry is studied using polarized microscopy. A combination of polarized and dark-field microscopy facilitated characterization of the defects; specific structural models are proposed. A new alignment technique involving compression and dilation of the lipid, which effects sample alignment at temperatures that are lower than those required by the Powers technique, is described. Lower temperature alignment avoids thermal decomposition that will sometimes occur if the lipid is maintained at elevated temperatures for prolonged periods. With this technique, samples of dilaurylphosphatidylcholine with 20% water by weight were aligned at room temperature.Engineering and Applied Science
Cancer Awareness in Alternative Settings: Lessons Learned and Evaluation of the Barbershop Men’s Health Project
Prostate and colorectal cancer are two of the leading causes of cancer deaths among African American men. This study describes lessons learned from the development, implementation and evaluation of a culturally appropriate, barbershop-based intervention to improve prostate and colorectal cancer screening awareness among African American men. Working with an Advisory Panel of shop owners, barbers, and cancer survivors, local barbers were recruited and trained as Community Health Advisors to educate, motivate, and assist their clients in becoming more knowledgeable about prostate and colorectal cancer. Survey results reveal increases in prostate and colorectal cancer knowledge and self-reported screening among participants. Lessons learned include the need for adequate project staffing and the appropriate role of the barber as a Community Health Advisor. Findings from this study suggest that barbershops are a promising setting for reaching African American men and could be used to target additional conditions that disproportionately impact this community
The 2.5-5.0 micron spectra of Io: Evidence for H2S and H2O frozen in SO2
The techniques of low temperature spectroscopy are applied to identify the constituents of the ices covering the surface of Io, a satellite of Jupiter. Infrared spectra of Io in the 4000-2000 cm exp -1 region, including new observational data, are analyzed using laboratory studies of plausible surface ices
Laboratory simulation of the photoprocessing and warm-up of cometary and pre-cometary ices: Production of complex organic molecules
The recent missions to Comet Halley detected large quantities of organic material on grains as well as organic molecules in the gas phase. A possible origin of these materials is the energetic processing of ice mantles on the grains prior to comet formation, either in the pre-solar nebula or the interstellar medium. This process was simulated in the laboratory by depositing interstellar ice analogs (H2O/CH3OH/CO/NH3) on a cold (10 K) substrate with simultaneous UV irradiation. The material evaporating during warm-up of the photolyzed ice as well as the residue remaining at room temperature was analyzed by a number of techniques. It was found that a large number of organic molecules of various complexity are synthesized during the simulation process, stressing the possible significance of UV photolysis for producing the organic Comet material
The Use of Teletherapy in the Mainstreaming Era
Results of research appears to indicate that peer acceptance is vital to a successful mainstreaming process. If understanding is to be fostered in children, teachers must provide class members with opportunities for building acceptance. One highly effective and inexpensive method of building empathy and increasing the probability of peer acceptance is the use of Teletherapy
Near Infrared Spectra of H2O/HCN Mixtures
Cassini's VIMS has already returned exciting results interpreting spectra of Saturn's icy satellites. The discovery of unidentified features possibly due to CN compounds inspired the work reported here. We wanted to test HCN as a possibility for explaining these features, and also explore how the features of HCN change when mixed with H2O. We have previously noted that mixing H20 and CO2 produces new spectral features and that those features change with temperature and mixing ratio
A computational approach to implicit entities and events in text and discourse
In this paper we will focus on the notion of “implicit”
or lexically unexpressed linguistic elements that are
nonetheless necessary for a complete semantic interpretation
of a text. We refer to “entities” and “events” because
the recovery of the implicit material may affect all the modules
of a system for semantic processing, from the grammatically
guided components to the inferential and reasoning
ones. Reference to the system GETARUNS offers one possible
implementation of the algorithms and procedures needed
to cope with the problem and enables us to deal with all the
spectrum of phenomena. The paper will address at first the
following three types of “implicit” entities and events:
– the grammatical ones, as suggested by a linguistic theories
like LFG or similar generative theories;
– the semantic ones suggested in the FrameNet project, i.e.
CNI, DNI, INI;
– the pragmatic ones: here we will present a theory and an
implementation for the recovery of implicit entities and
events of (non-) standard implicatures.
In particular we will show how the use of commonsense
knowledge may fruitfully contribute to find relevant implied
meanings. Last Implicit Entity only touched on, though for
lack of space, is the Subject of Point of View, which is computed
by Semantic Informational Structure and contributes
the intended entity from whose point of view a given subjective
statement is expressed
Synthesis, Structure, and Activity of Enhanced Initiators for Olefin Metathesis
A series of ruthenium olefin metathesis catalysts of the general structure (H_2IMes)(PR_3)(Cl)_2Ru CHPh (H_2IMes = 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) have been prepared; these complexes are readily accessible in two steps from commercially available (H_2IMes)(PCy_3)(Cl)_2Ru CHPh. Their phosphine dissociation rate constants (k_1), relative rates of phosphine reassociation, and relative reaction rates in ring-opening metathesis polymerization (ROMP) and ring-closing metathesis (RCM) have been investigated. The rates of phosphine dissociation (initiation) from these complexes increase with decreasing phosphine donor strength. Complexes containing a triarylphosphine exhibit dramatically improved initiation relative to (H_2IMes)(PCy_3)(Cl)_2Ru CHPh. Conversely, phosphine reassociation shows no direct correlation with phosphine electronics. In general, increased phosphine dissociation leads to faster olefin metathesis reaction rates, which is of direct significance to both organic and polymer metathesis processes
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