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81.
82.
We describe the origins of fuzzy-trace theory, including Piagetian, interference, information-processing, and judgment and decision-making influences. The contrasting properties of gist and verbatim memory serve as its foundation and, in recent models of spontaneous and implanted false memories, explain seemingly contradictory developmental trends, such as reverse developmental findings, differential time courses for true and false memories, and conflicting effects of trace strength. However, approaches that integrate fuzzy-trace theory with neurological, social, emotional, and motivational perspectives are needed. A method for accomplishing this integration, using the recent models, is introduced and new research that spans these perspectives is discussed. Relations to other contemporary theories, especially source-monitoring and dual-process theories, are also explained. We conclude by rejecting the notion that spontaneous false memories are actually "true" and distinguish gist and verbatim senses of the term "true" that have different consequences in real life.  相似文献   
83.
The effect of tone duration on fundamental frequency (F0) discrimination is greater for complexes containing unresolved harmonics than for those containing resolved harmonics [Plack and Carlyon, J. Acoust. Soc. Am. 98, 1355-1364 (1995)]. Three experiments explored this effect further. The first experiment measured sensitivity (as d') to fundamental frequency (F0) differences for two complexes, both with an F0 of 250 Hz. The first complex was low-pass filtered at 1875 Hz to create a resolved complex and the second was bandpass filtered between 5500 and 7500 Hz to create an unresolved complex. The harmonics for the resolved complex were selected so that no two harmonics were the same between the two observation intervals. Performance for both complexes was measured for tone durations of 20, 40, 80, and 160 ms. For the unresolved complex, the effect of duration was greater than that for the resolved complex and greater than the predictions of a "multiple-looks" model assuming either peripheral (before sampling) or central (after combining samples) sources of variance. The second experiment replicated these results using an F0 of 62.5 Hz with the cutoff frequencies of the bandpass filters divided by four, confirming that the effect is related to resolvability and not to spectral region. In the final experiment, F0 discrimination for pairs of complexes separated by a temporal gap was measured relative to that for one complex. Performance for the resolved and unresolved complexes was similar: Very little effect of gap duration was observed and the results were consistent with the predictions of the peripheral-variance multiple-looks model. Taken together, the results suggest that the pitch mechanism for resolved harmonics uses a relatively short sampling window of around 20 ms, while the mechanism for unresolved harmonics may use a more complex strategy for optimizing the combination of information over time, perhaps involving a flexible integration time.  相似文献   
84.
OBJECTIVES: To i) document the sensitivity and specificity of a combined scintigraphic/lactulose breath hydrogen test for small intestinal bacterial overgrowth and ii) investigate the validity of currently accepted definitions of an abnormal lactulose breath hydrogen test based on "double peaks" in breath hydrogen concentrations. METHODS: Twenty-eight subjects were investigated with culture of proximal small intestinal aspirate and a 10-g lactulose breath hydrogen test combined with scintigraphy. Gastroduodenal pH, the presence or absence of gastric bacterial overgrowth, and the in vitro capability of overgrowth flora to ferment lactulose were determined. RESULTS: Sensitivity (16.7%) and specificity (70.0%) of the lactulose breath hydrogen test alone for small intestinal bacterial overgrowth were poor. Combination with scintigraphy resulted in 100% specificity, because double peaks in serial breath hydrogen concentrations may occur as a result of lactulose fermentation by cecal bacteria. Sensitivity increased to 38.9% with scintigraphy, because a single rise in breath hydrogen concentrations, commencing before the test meal reaches the cecum, may occur in this disorder. Sensitivity remained suboptimal irrespective of the definition of small intestinal bacterial overgrowth used, the nature of the overgrowth flora, favorable luminal pH, the presence of concurrent gastric bacterial overgrowth, or the in vitro ability of the overgrowth flora to ferment lactulose. CONCLUSIONS: Definitions of an abnormal lactulose breath hydrogen test based on the occurrence of double peaks in breath hydrogen concentrations are inappropriate. Not even the addition of scintigraphy renders this test a clinically useful alternative to culture of aspirate for diagnosing small intestinal bacterial overgrowth.  相似文献   
85.
BACKGROUND & AIMS: Antineutrophil cytoplasmic antibodies (ANCA) have been consistently detected in a subgroup of patients with Crohn's disease (CD). This study was designed to determine whether serum ANCA expression in patients with CD characterizes an identifiable clinical subgroup. METHODS: The study population consisted of 69 consecutive patients with an established diagnosis of CD as determined by a combination of characteristic clinical, radiographic, endoscopic, and histopathologic criteria. Sera from the patients were analyzed for the presence of ANCAs using the fixed neutrophil enzyme-linked immunosorbent assay (ELISA) assay. Perinuclear ANCA (pANCA)-positive and cytoplasmic ANCA (cANCA)-positive results by ELISA were confirmed by indirect immunofluorescence staining. Clinical profiles of the ANCA-positive patients with CD were compared with those of patients with CD not expressing ANCA (ANCA-negative). RESULTS: pANCA-positive patients with CD have endoscopically and/or histopathologically documented left-sided colitis and symptoms of left-sided colonic inflammation, clinically reflected by rectal bleeding and mucus discharge, urgency, and treatment with topical agents. One hundred percent of patients with CD expressing pANCA had "UC-like" features. CONCLUSIONS: In patients with CD, serum pANCA expression characterizes a UC-like clinical phenotype. Stratification of CD by serum pANCA provides evidence of heterogeneity within CD and suggests a common intestinal mucosal inflammatory process among a definable subgroup of patients with CD and UC expressing this marker.  相似文献   
86.
We describe a general ab initio and non-perturbative method to solve the time-dependent Schrödinger equation (TDSE) for the interaction of a strong attosecond laser pulse with a general atom. While the field-free Hamiltonian and the dipole matrices may be generated using an arbitrary primitive basis, they are assumed to have been transformed to the eigenbasis of the problem before the solution of the TDSE is propagated in time using the Arnoldi–Lanczos method. Probabilities for survival of the ground state, excitation, and single ionization can be extracted from the propagated wavefunction.

Program summary

Program title: ALTDSECatalogue identifier: AEDM_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDM_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 2154No. of bytes in distributed program, including test data, etc.: 30 827Distribution format: tar.gzProgramming language: Fortran 95. [A Fortran 2003 call to “flush” is used to simplify monitoring the output file during execution. If this function is not available, these statements should be commented out.].Computer: Shared-memory machinesOperating system: Linux, OpenMPHas the code been vectorized or parallelized?: YesRAM: Several Gb, depending on matrix size and number of processorsSupplementary material: To facilitate the execution of the program, Hamiltonian field-free and dipole matrix files are provided.Classification: 2.5External routines: LAPACK, BLASNature of problem: We describe a computer program for a general ab initio and non-perturbative method to solve the time-dependent Schrödinger equation (TDSE) for the interaction of a strong attosecond laser pulse with a general atom [1,2]. The probabilities for survival of the initial state, excitation of discrete states, and single ionization due to multi-photon processes can be obtained.Solution method: The solution of the TDSE is propagated in time using the Arnoldi–Lanczos method. The field-free Hamiltonian and the dipole matrices, originally generated in an arbitrary basis (e.g., the flexible B-spline R-matrix (BSR) method with non-orthogonal orbitals [3]), must be provided in the eigenbasis of the problem as input.Restrictions: The present program is restricted to a 1Se initial state and linearly polarized light. This is the most common situation experimentally, but a generalization is straightforward.Running time: Several hours, depending on the number of threads used.References: [1] X. Guan, O. Zatsarinny, K. Bartschat, B.I. Schneider, J. Feist, C.J. Noble, Phys. Rev. A 76 (2007) 053411. [2] X. Guan, C.J. Noble, O. Zatsarinny, K. Bartschat, B.I. Schneider, Phys. Rev. A 78 (2008) 053402. [3] O. Zatsarinny, Comput. Phys. Comm. 174 (2006) 273.  相似文献   
87.
Sulfated alkanolamides of hydrogenated tallow fatty acids have been shown to possess excellent lime soap dispersing and detergent properties. However the high melting points of the alkanolamides and their relative insolubility in organic solvents such as dichloroethane make sulfation on an industrial scale awk ward. This difficulty has been overcome by the use of a eutectic mixture of the N-(2-hydroxypropyl)amide and N-(2-[2-hydroxyethoxy]ethyl)amide of unhydrogenated tallow fatty acids. The sulfation of such a mixture can be carried out at or slightly above room temperature, and only a small amount of a chlorinated solvent is required in order to keep the sulfation mixture fluid. The resulting sulfated mixed alkanolamide is an excellent lime soap dispersing agent, which is formulated readily with tallow soap and a glassy silicate into an effective heavy duty detergent.  相似文献   
88.
Compact tension specimens of a rigid polyurethane foam have been tested in fatigue and crack growth has been monitored visually and by means of acoustic emission (AE). During the load cycle it has been found possible to resolve the AE activity into four regions: the crack faces un-sticking, fracture events at or close to peak load, a period of zero AE just after peak load, and AE associated with crack closure lower down the unloading part of the cycle. The fracture AE has been found to increase rapidly with crack length — consistent with a seventh power dependence on K — and to occur during every cycle at high K values, but to be absent in an increasingly greater proportion of cycles as K is decreased below about 40 kPa m1/2. AE data obtained on samples in which crack growth occurred across the layers of foam, through the high density inter-layer skins, show that the technique is very sensitive to the crack retardation effect associated with these skins well before this retardation is detectable visually.  相似文献   
89.
This study extended client-focused research by using the nearest neighbor (NN) approach, a client-specific sampling and prediction strategy derived from research on alpine avalanches. Psychotherapy clients (N = 203) seen in routine practice settings in the United Kingdom completed a battery of intake measures and then completed symptom intensity ratings before each session. Forecasts of each client's rate of change and session-by-session variability were computed on the basis of that client's NNs (n = 10-50 in different comparisons). Alternative forecasts used linear or log-linear slopes and were compared with an alternative prediction strategy. Results showed that the NN approach was superior to the alternative model in predicting rate of change, though the advantage was less clear for predicting variability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
The effect of bone plug length and Kurosaka screw (DePuy, Warsaw, IN) diameter on graft holding strength of the bone-tendon-bone construct was determined. Random length porcine bone plugs were assigned to fixation with 7 or 9 mm Kurosaka screws. Peak load to failure was determined. There was a significant decrease in peak load to failure of the 5-mm long bone plugs compared with longer bone plugs. No difference was found between longer lengths of bone plug in either the 7- or 9-mm screw diameter groups. The 9-mm diameter screws significantly increased peak load to failure for both 1- and 2-cm bone plug lengths.  相似文献   
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