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Absorption spectra of polycrystalline samples of LiUF6, α-NaUF6, and CsUF6 have been recorded at 4, 77, and 298 K. This group of compounds has a common sixfold U–F coordination that approaches an octahedral site symmetry for LiUF6 but exhibits increasing trigonal distortion (D3d symmetry) along the indicated series. Spectra have been systematically interpreted as consisting of sequences of vibronic transitions coupled to well-defined electronic excited states. Crystal-field calculations have been performed. [ABSTRACT FROM AUTHOR]

Almost a hundred years ago, the Russian filmmaker Lev Kuleshov conducted his now famous editing experiment in which different objects were added to a given film scene featuring a neutral face. It is said that the audience interpreted the unchanged facial expression as a function of the added object (e.g., an added soup made the face express hunger). This interaction effect has been dubbed “Kuleshov effect.” In the current study, we explored the role of sound in the evaluation of facial expressions in films. Thirty participants watched different clips of faces that were intercut with neutral scenes, featuring either happy music, sad music, or no music at all. This was crossed with the facial expressions of happy, sad, or neutral. We found that the music significantly influenced participants’ emotional judgments of facial expression. Thus, the intersensory effects of music are more specific than previously thought. They alter the evaluation of film scenes and can give meaning to ambiguous situations. [ABSTRACT FROM AUTHOR]

Finding time and cost efficiencies associated with preliminary and final design of transportation projects has become increasingly difficult. Major new complexities present interesting and challenging project management issues and many agencies have incrementally adapted the project development process to improve efficiencies. Yet our understanding of the project development process is limited and the incremental changes in the process have not resulted in major modifications in the way in which transportation project development is approached for most agencies. A time honored method for elucidating problems with project development and potential solutions to them has been through the use of governmental audits. For example, over the past 30 years some 14 performance audits and evaluations have conducted of the California transportation project development process. These California audits have suggested that voter or legislatively approved projects, in terms of time, cost, or scope, significantly enhance project efficiencies. In this study, we examine time and cost project development efficiencies between voter or legislatively approved projects and projects with standard scopes. We find no significant evidence that state highway projects with highly defined, voter or legislatively approved project scopes, time, or costs are any more likely to have lower project development costs or times than projects with non-voter approved scopes. [Copyright &y& Elsevier]

To deal with hardware reliability requirements of critical real-time computer applications, fault-tolerance provisions have become a widely accepted practice. Failures of software executing on these computers is equally critical, and the extension of fault tolerance to software is therefore desirable but it needs to be implemented in a specific manner. Redundancy in fault-tolerant software requires program that are deliberately different from the original ones which they are intended to back up. Error detection and rollback provisions must be as independent as possible of the software segments which they protect. The recovery block concept pioneered by Randell meets these requirements. Skeleton routines are presented that illustrate the application of the recovery block to real-time programs, particularly those dealing with navigation and attitude control. The concept is seen to be compatible with certain ad hoc fault-tolerance techniques that are currently employed. A technique for reliability analysis of the resulting software system is developed. While specific software failure data are unfortunately not yet available, the exercise of this reliability model with a range of hypothetical failure rates shows that a very appreciable desensitization of the overall computer performance to software errors is possible by use of these fault-tolerance provisions. Economic factors of applying fault-tolerant software are discussed. Memory coat for the additional software segments is an obstacle at present but will probably shrink to insignificance in the future. A positive approach to the fault-tolerant software concepts seems warranted. A program for research to more fully explore the capabilities and limitations is suggested. [ABSTRACT FROM AUTHOR]

Studies the impact of plaque imaging by electron beam tomography on the treatment of dyslipidemias. Definition of dyslipidemia; Identification of risk factors; Adequacy of lipid treatment.

Electron-beam tomography (EBT) plaque imaging has the potential to fundamentally change the practice of prevention, through application of the following principles: (1) Asymptomatic patients with significant calcified plaque should be considered to have a clinical coronary artery disease risk equivalent. (2) Measurement of nontraditional parameters should be incorporated into the evaluation of patients with calcified plaque. (3) Drug treatment should focus on the asymptomatic patient with subclinical atherosclerosis. (4) Change in plaque rather than change in lipid values should guide treatment. [ABSTRACT FROM AUTHOR]

• We examined which variables (perceived TTP, speed, or distance) guide gap selection. • Camera-height effects surfaced in gap selection, TTP, and distance estimation. • A high camera led to longer distance and TTP estimates, and smaller selected gaps. • Regression analyses revealed the high importance of distance information. • Drivers seem to use distance-based strategies in TTP estimation and gap selection. Selecting a safe gap before merging into the traffic is a crucial driving skill that relies on images provided by rear-view mirrors or, recently, camera-monitor systems. When using these visual aids, some drivers select dangerously small gaps to cut in front of faster vehicles. They may do so because they base their decision either on information about distance or object size, or on miscalculated information about time-to-passage (TTP). Previous experiments have been unable to compare the role of TTP, speed, and distance information for drivers' gap selection, as they did not investigate them in the same experimental regime. The present experiments seek to determine the perceptual variables that guide drivers' rearward gap selection. Using short videos of an approaching vehicle filmed from three different camera heights (low, conventional, high), a total of 61 subjects either made gap safety decisions (Experiment I), or estimated the TTP, speed, and distance of an approaching vehicle (Experiment II). An effect of camera height was found for gap selection, TTP, and distance estimation, but not for speed estimation. For the high camera position, smaller gaps were selected as safe, TTP estimates were longer, and the distance to the approaching vehicle was perceived as farther. An opposite pattern was found for the low camera. Regression analyses suggested that distance is an important player. The subjects strongly relied on distance information when estimating TTP, and perceived distance dominated subjects' gap selection. Thus, drivers seem to employ distance-based strategies when selecting safe gaps in rear-view mirrors or monitors. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neuromodulation is a therapeutic option to improve limb salvage in end-stage peripheral arterial disease (PAD), but there is no consensus on its indication for spinal cord stimulation (SCS) in PAD patients. OBJECTIVE: The aim of this study was to present the outcome of end-stage PAD patients treated with SCS. METHODS: This study is a retrospective analysis based on a local prospective registry. Neuromodulation was performed if there was: 1) no revascularisation option, 2) no septicemia, 3) and Rutherford stage 4–6. The primary endpoint of the study was limb salvage. Secondary endpoints were reduction in pain or simply pain reduction pain (assessed using a visual anlog scale/VAS) and improvement in walking distance. RESULTS: Limb salvage was reached in 30/34 patients (88%). Patients reported a significant reduction in pain on the 10-point VAS scale from baseline (median = 7.5, IQR = 7–8) to follow-up at 2 years (median = 0, IQR 0–2.75), p < 0.001. Walking distance also improved from preoperative (median = 50 m, IQR = 20–50 m) to follow-up at 2 years (median = 150 m, IQR 50–272 m), p < 0.001. RESULTS: SCS implantation in patients with end-stage PAD can enable limb salvage in a high percentage of cases and increase mobility due to pain reduction. The role of microcirculation in these improvements needs to be investigated in further studies. [ABSTRACT FROM AUTHOR]

Photocurrent microscopy is used to characterize the kinetics of electrons and holes in organic field-effect transistors (FETs) with the hydrogen-bonded pigment epindolidione as active layer. The method relies on electrons and holes, generated on local illumination, which are provided after exciton splitting, to probe charge trapping. In the dark, hole conduction is observed for negative gate voltage while no electron conduction is observed for positive gate voltage. However, under illumination, a fast displacement current with 60 μs onset time and 1 ms exponential decay occurs for positive gate voltage, which can be explained by exciton splitting underneath the semitransparent top contact followed by subsequent electron trapping and hole extraction. Afterward, trapped electrons hop via further trap states within the film to the insulator into interface traps (13 ms exponential decay) which induce a positive threshold voltage shift in the FET transfer curves for hole transport. Photocurrent microscopy confirms that the displacement current occurs only for illumination under and near the semitransparent source/drain contacts, which act here as metal-insulator-semiconductor (MIS) diodes. For negative gate voltage instead, the photocurrent comprises an enhanced hole current in the FET channel between the contacts. In the channel region, the detrapping of holes at the interface with the insulator (3 ms time constant) enhances the transistor current at low frequencies <1 kHz, whereas the displacement current between the contacts and the gate is observed only at frequencies >10 kHz. Thus, we show here that photocurrent microscopy allows to identify the kinetics of electrons and holes in traps close to the contacts and in the FET channel of pigment transistors. [ABSTRACT FROM AUTHOR]

Do the increasingly popular 3D movies change how we perceive the content of the movie? We presented short (3.21 min) film sequences to observers equipped with shutter glasses. Three genres (horror, action, and documentary) were crossed with three between-subjects viewing conditions (director’s 3D, artificial 3D, and 2D). Observers had to rate how the film impressed them in terms of arousal, motion sickness, presence, and immersion. They also judged the personality, attractiveness, and intelligence of the protagonist in all viewing conditions. Not surprisingly, horror films produced more arousal and presence than action films. Documentaries scored lowest on presence. Action movies produced the highest immersion ratings. 2D viewing tended to produce less presence than 3D viewing. Surprisingly, artificial 3D was indistinguishable in terms of presence from the director’s 3D. The same was true for motion sickness: 3D viewing, regardless whether intended by the director or introduced artificially, was more nauseating than 2D viewing. We also found a genre effect regarding the impression of the protagonist, the latter was more agreeable in documentaries presented in 2D. The same protagonist was judged to be less extroverted and weighing more when viewed in director’s 3D. We conclude that 3D film has complex effects that interact with the film genre. Directors should consider these interactions when planning to produce a 3D movie. [ABSTRACT FROM AUTHOR]

Practice guidelines for the use of electron beam tomography to detect and quantitate coronary atherosclerotic plaque burden have been formulated by the Society of Atherosclerosis Imaging using American College of Cardiology/American Heart Association classifications of indications. [ABSTRACT FROM AUTHOR]

This investigation determined the prevalence of low-density lipoprotein (LDL) subclass distribution abnormalities, elevated lipoprotein(a) (Lp(a)), and elevated total plasma homocysteine in asymptomatic subjects with subclinical coronary artery disease determined by electron beam tomography (EBT). Fifty-five percent of subjects were classified as higher risk patients and 45% as lower risk patients, employing the National Cholesterol Education Program (NCEP) lipid criteria. EBT was performed in 296 consecutive asymptomatic subjects, and blood was analyzed for total, LDL, and high-density lipoprotein (HDL) cholesterol, triglycerides, LDL subclass distribution by S(3) gradient gel electrophoresis, Lp(a), and total homocysteine. Disorders of LDL subclass distribution were the most common disorder with 60.6% of the population expressing a distribution in the small regions IIIa + IIIb of >20%; and this was more common in the NCEP higher risk group (LDL cholesterol > or =130 and/or HDL cholesterol <35 mg/dl) (p <0.0004). A Lp(a) value >25 mg/dl was found significantly more often in the NCEP higher (36.9%) compared with lower (14.3%) risk group (p <0.001). None of the laboratory measurements correlated with the calcium score or calcium score percentile rank, with the exception of a weak correlation of mean LDL peak particle diameter and calcium percentile (r = 0.14, p = 0.02). Determination of metabolic disorders in addition to LDL cholesterol and HDL cholesterol increased the diagnostic yield from 55.1%, based on NCEP lipid criteria, to 84.1% with the addition of LDL subclass distribution, Lp(a), and total homocysteine. We conclude that: (1) disorders of LDL subclass distribution and elevated Lp(a) occur frequently in NCEP higher risk patients with subclinical coronary artery disease and are the only identifiable disorders in lower NCEP risk patients; and (2) electron beam tomographic evaluation and determination of LDL subclass distribution and Lp(a) should be considered for incorporation into primary prevention guidelines. [ABSTRACT FROM AUTHOR]

This study was designed to determine whether the National Cholesterol Education Program (NCEP) lipid guidelines accurately identify subclinical atherosclerosis and whether low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels are related to the extent and prematurity of coronary artery disease (CAD) as determined by electron beam tomography (EBT). Out of personal concern for CAD risk, 930 consecutive asymptomatic subjects, without clinical CAD and on no lipid-lowering agents, underwent EBT. Calcium score and percentile were correlated with total cholesterol (TC), LDL-C, HDL-C, triglycerides, and demographic parameters. A calcium score of > 0 (EBT+) was found in 55% of patients; 45% of patients had a 0 score (EBT-). Mean age (58.0 +/- 10.5 vs 49.3 +/- 9.7 years, p = 0.0001), TC (218 +/- 39 vs 211 +/- 41 mg/dl, p = 0.006), LDL-C (136 +/- 36 vs 127 +/- 27 mg/dl, p = 0.005), and TC/HDL-C (4.6 +/- 1.4 vs 4.2 +/- 1.5, p = 0.0001) were significantly higher and HDL-C (52.2 +/- 17.6 vs 55.4 +/- 19.3 mg/dl, p = 0.008) lower in the EBT+ compared with EBT- group. In the EBT+ group, 75.1% of subjects had LDL-C < 160 mg/dl and would not be advised to use lipid-lowering medications according to NCEP guidelines. In subjects with LDL-C < 160 mg/dl, 51.8% of subjects were EBT+, as were 46.1% of those with LDL-C < 100 mg/dl. There were no significant differences in the calcium scores throughout the entire range of all lipid parameters; calcium percentiles were virtually identical within lipid value subgroups. We conclude that asymptomatic patients with EBT-defined subclinical atherosclerosis are not reliably identified by NCEP guidelines, and TC, LDL-C, HDL-C, TC/HDL-C, and triglyceride levels do not correlate with either the extent or prematurity of calcified plaque burden. [ABSTRACT FROM AUTHOR]