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61.
Examined the Maine Scale (MS) in 3 studies (131 18–60 yr old hospitalized psychiatric patients) in which adequate test–retest and independent interrater reliabilities were obtained. In an examination of construct validity, high scores on the Nonparanoid subscale were associated with external locus of control; poor performance on the Stanford-Binet Intelligence Scale Vocabulary, the Expanded Similarities Test, and the Embedded Figures Test; conceptual overinclusion; slow RT; deviant word associations; and poor recall of word associations. In an examination of concurrent validity, the MS Paranoid and Nonparanoid subscales correlated significantly with the corresponding subscales of the Symptom Rating Scale and the Symptom-Sign Inventory. The MS subscales also correlated significantly with the Weighted Symptom-Sign Inventory and the New Haven Schizophrenia Index but were better able to discriminate between paranoid and schizophrenic categories than any of the other scales. Factor analyses showed a schizophrenic and paranoid factor in both studies. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Vrba J Robinson SE Mccubbin J Lowery CL Eswaran H Wilson JD Murphy P Preissl H 《IEEE transactions on bio-medical engineering》2004,51(7):1207-1218
The fetal magnetoencephalogram (fMEG) is measured in the presence of large interference from the maternal and fetal magnetocardiograms. This interference can be efficiently attenuated by orthogonal projection of the corresponding spatial vectors. However, the projection operators redistribute the fMEG signal among sensors. Although redistribution can be readily accounted for in the forward solution, visual interpretation of the fMEG signal topography is made difficult. We have devised a general, model-independent method for correction of the redistribution effect that utilizes the assumption that we know in which channels the fMEG should be negligible (such channels are distant from the known fetal head position). In a simplified case where the fMEG can be explained by equivalent current dipoles, the correction can also be obtained from fitting the dipoles to the fMEG signal. The corrected fMEG signal topography then corresponds to the dipole forward solution, but without orthogonal projection. We illustrate the redistribution correction on an example of experimentally measured flash evoked fMEG. 相似文献
63.
Geng W Cosman P Berry CC Feng Z Schafer WR 《IEEE transactions on bio-medical engineering》2004,51(10):1811-1820
This paper presents a method for automatic tracking of the head, tail, and entire body movement of the nematode Caenorhabditis elegans (C. elegans) using computer vision and digital image analysis techniques. The characteristics of the worm's movement, posture and texture information were extracted from a 5-min image sequence. A Random Forests classifier was then used to identify the worm type, and the features that best describe the data. A total of 1597 individual worm video sequences, representing wild type and 15 different mutant types, were analyzed. The average correct classification ratio, measured by out-of-bag (OOB) error rate, was 90.9%. The features that have most discrimination ability were also studied. The algorithm developed will be an essential part of a completely automated C. elegans tracking and identification system. 相似文献
64.
Wiggins Jack G.; Bennett Bruce E.; Batchelor Walter F.; West Pamela R. 《Canadian Metallurgical Quarterly》1983,38(5):602
The professional and economic challenges to psychologists posed by organized medicine have been stymied in the past by the Federal Trade Commission and by strict enforcement of the antitrust laws. Now that professionals' competition and consumer choice are being supported in the courts, the American Medical Association (AMA) is redoubling its efforts to retain a monopolistic hold on health care, hospital practice, and health insurance throughout the nation. Organized psychology, with the help of other professions and the Congress, has barely held the line against politically and economically stronger forces. The Association for the Advancement of Psychology and the American Psychological Association actively opposed the AMA's proposed legislation in 1981 and 1982 that would have allowed the AMA to circumvent valid law. The medical profession has actively worked to control all health care and deny psychologists hospital staff privileges, preventing group practice between physicians and psychologists, denying them health insurance reimbursement, and restricting psychological services to physician supervision. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Drake PL Lawryk NJ Ashley K Sussell AL Hazelwood KJ Song R 《Journal of hazardous materials》2003,102(1):29-38
Two methods for measuring airborne lead using field-portable instruments have been developed by the National Institute for Occupational Safety and Health (NIOSH): Method 7702 uses X-ray fluorescence (XRF), and Method 7701 employs ultrasonic extraction (UE) followed by anodic stripping voltammetry (ASV). The two portable methods were evaluated at mining sites. Area air samples were collected throughout two mills where ore from nearby mines was processed; the primary constituent of the ore was lead sulfide (galena). The air samples were collected on 37 mm mixed cellulose ester membrane filters housed within plastic filter cassettes. At the end of the work shift, the cassettes were collected and taken to a room off-site for analysis by the two portable methods. The filter samples were first analyzed by XRF and then by UE/ASV. Calibration was verified on both instruments according to standard procedures. The samples were then sent for confirmatory analysis via flame atomic absorption spectrometry (FAAS) according to NIOSH Method 7082. Pairwise comparisons between the methods using the paired t-test showed no statistically significant differences between ASV and FAAS (P>0.05); however, the comparison between XRF and FAAS was statistically significant (P<0.05). The elevated lead concentrations reported by XRF relative to FAAS were likely the result of the ability of XRF to report total lead, including lead silicates. This form of lead is not liberated in the digestion process prior to FAAS analysis, and is therefore not detected by this method. Despite this discrepancy, lead concentrations measured by both portable technologies were found to be highly correlated with the laboratory method (R2>0.96), suggesting that they are suitable as screening methods for airborne lead at mining sites. 相似文献
66.
Microchip-based purification of DNA from biological samples 总被引:10,自引:0,他引:10
Breadmore MC Wolfe KA Arcibal IG Leung WK Dickson D Giordano BC Power ME Ferrance JP Feldman SH Norris PM Landers JP 《Analytical chemistry》2003,75(8):1880-1886
A microchip solid-phase extraction method for purification of DNA from biological samples, such as blood, is demonstrated. Silica beads were packed into glass microchips and the beads immobilized with sol-gel to provide a stable and reproducible solid phase onto which DNA could be adsorbed. Optimization of the DNA loading conditions established a higher DNA recovery at pH 6.1 than 7.6. This lower pH also allowed for the flow rate to be increased, resulting in a decrease in extraction time from 25 min to less than 15 min. Using this procedure, template genomic DNA from human whole blood was purified on the microchip platform with the only sample preparation being mixing of the blood with load buffer prior to loading on the microchip device. Comparison between the microchip SPE (microchipSPE) procedure and a commercial microcentrifuge method showed comparable amounts of PCR-amplifiable DNA could be isolated from cultures of Salmonella typhimurium. The greatest potential of the microchipSPE device was illustrated by purifying DNA from spores from the vaccine strain of Bacillus anthracis, where eventual integration of SPE, PCR, and separation on a single microdevice could potentially enable complete detection of the infectious agent in less than 30 min. 相似文献
67.
Peripheral neural stimulation is a major problem in current gradient coil designs. Induced current problems in patients relate
directly to gradient strength and modulation frequency. Current designs of gradient coil tend to limit ultra-high-speed imaging
methods such as echo-planar imaging through the effect of induced currents which produce tingling sensations and involuntary
muscle twitch. Neural stimulation could also trigger epileptic fits and/or cardiac fibrillation. For reduction of induced
currents, an important aspect is the coil geometry. It is desirable to design the gradient coil in such a way as to prevent
closed loop circulating currents within the body. Preliminary results using a four-sector gradient coil with rectangular geometry,
operating in a low mutual coupling mode, indicate significant reduction in the E-field within the subject volume of the coil. Reduction in induced currents in the patient allows safer operation at higher
magnetic field strengths together with faster scans currently prohibited through neural stimulation effects in standard coil
geometries. 相似文献
68.
Data collected from a field study of in situ zero-valent iron treatment for TCE were analyzed in the context of coupled transport and reaction processes. The focus of this analysis was to understand the behavior of chemical components, including contaminants, in groundwater transported through the iron cell of a pilot-scale funnel and gate treatment system. A multicomponent reactive transport simulator was used to simultaneously model mobile and nonmobile components undergoing equilibrium and kinetic reactions including TCE degradation, parallel iron dissolution reactions, precipitation of secondary minerals, and complexation reactions. The resulting mechanistic model of coupled processes reproduced solution chemistry behavior observed in the iron cell with a minimum of calibration. These observations included the destruction of TCE and cis-1,2-DCE; increases in pH and hydrocarbons; and decreases in EH, alkalinity, dissolved O2 and CO2, and major ions (i.e., Ca, Mg, Cl, sulfate, nitrate). Mineral precipitation in the iron zone was critical to correctly predicting these behaviors. The dominant precipitation products were ferrous hydroxide, siderite, aragonite, brucite, and iron sulfide. In the first few centimeters of the reactive iron cell, these precipitation products are predicted to account for a 3% increase in mineral volume per year, which could have implications for the longevity of favorable barrier hydraulics and reactivity. The inclusion of transport was key to understanding the interplay between rates of transport and rates of reaction in the field. 相似文献
69.
The use of robots, especially autonomous mobile robots, to support work is expected to increase over the next few decades. However, little empirical research examines how users form mental models of robots, how they collaborate with them, and what factors contribute to the success or failure of human-robot collaboration. A two-year observational study of a collaborative human-robot system suggests that the factors disrupting the creation of common ground for interactive communication change at different levels of robot autonomy. Our observations of users collaborating with the remote robot showed differences in how the users reached common ground with the robot in terms of an accurate, shared understanding of the robot's context, planning, and actions - a process called grounding. We focus on how the types and levels of robot autonomy affect grounding. We also examine the challenges a highly autonomous system presents to people's ability to maintain a shared mental model of the robot 相似文献
70.
David A. Palandro Serge Andréfouët Chuanmin Hu Pamela Hallock Frank E. Müller-Karger Phillip Dustan Michael K. Callahan Christine Kranenburg Carl R. Beaver 《Remote sensing of environment》2008,112(8):3388-3399
The loss of coral reef habitats has been witnessed at a global scale including in the Florida Keys and the Caribbean. In addition to field surveys that can be spatially limited, remote sensing can provide a synoptic view of the changes occurring on coral reef habitats. Here, we utilize an 18-year time series of Landsat 5/TM and 7/ETM+ images to assess changes in eight coral reef sites in the Florida Keys National Marine Sanctuary, namely Carysfort Reef, Grecian Rocks, Molasses Reef, Conch Reef, Sombrero Reef, Looe Key Reef, Western Sambo and Sand Key Reef. Twenty-eight Landsat images (1984–2002) were used, with imagery gathered every 2 years during spring, and every 6 years during fall. The image dataset was georectified, calibrated to remote sensing reflectance and corrected for atmospheric and water-column effects. A Mahalanobis distance classification was trained for four habitat classes (‘coral’, ‘sand’, ‘bare hardbottom’ and ‘covered hardbottom’) using in situ ground-truthing data collected in 2003–2004 and using the spectral statistics from a 2002 image. The red band was considered useful only for benthic habitats in depths less than 6 m. Overall mean coral habitat loss for all sites classified by Landsat was 61% (3.4%/year), from a percentage habitat cover of 19% (1984) down to 7.6% (2002). The classification results for the eight different sites were critically reviewed. A detailed pixel by pixel examination of the spatial patterns across time suggests that the results range from ecologically plausible to unreliable due to spatial inconsistencies and/or improbable ecological successions. In situ monitoring data acquired by the Coral Reef Evaluation and Monitoring Project (CREMP) for the eight reef sites between 1996 and 2002 showed a loss in coral cover of 52% (8.7%/year), whereas the Landsat-derived coral habitat areas decreased by 37% (6.2%/year). A direct trend comparison between the entire CREMP percent coral cover data set (1996–2004) and the entire Landsat-derived coral habitat areas showed no significant difference between the two time series (ANCOVA; F-test, p = 0.303, n = 32), despite the different scales of measurements. 相似文献