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To determine predictive values of early visual and neurocognitive assessment in children with perinatally acquired haemorrhagic or ischaemic brain lesions selected on the basis of ultrasound, 63 children (37 boys, 26 girls), who had been followed and examined until the age of 18 months, were reexamined at 5 1/2 years. Good correlations between visual and neurodevelopmental assessments at 18 months and at 5 1/2 years were found. When ultrasound abnormalities were combined with early visual and neurocognitive assessment data, good predictive values, especially for the group of children who had grade 2 to 4 leukomalacia, were found for visual acuity and neurodevelopment.  相似文献   
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Existing measures for evaluating user performance on interaction tasks in virtual environments don't often provide sufficient information for improving these interactions. A new method for analyzing 3D goal-directed movements divides them into meaningful phases. The authors applied this method to experimental data collected for a 3D task resembling a standardized 2D multidirectional pointing task (ISO 9241-9). The results and analysis demonstrate that the method provides a more detailed insight into 3D goal-directed movements. This analysis can help researchers better identify input devices' and interaction techniques' strengths and weaknesses. This article is part of a special issue on 3D user interfaces.  相似文献   
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Mycobacterium tuberculosis (Mtb) represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the Mtb antigens TB10.4 and Ag85B. In mice, rLCMV elicited high frequencies of polyfunctional Mtb-specific CD8 and CD4 T cell responses. CD8 but not CD4 T cells were efficiently boosted upon vector re-vaccination. High-frequency responses were also observed in neonatally vaccinated mice, and co-administration of rLCMV with Expanded Program of Immunization (EPI) vaccines did not result in substantial reciprocal interference. Importantly, rLCMV immunization significantly reduced the lung Mtb burden upon aerosol challenge, resulting in improved lung ventilation. Protection was associated with increased CD8 T cell recruitment but reduced CD4 T cell infiltration upon Mtb challenge. When combining rLCMV with BCG vaccination in a heterologous prime-boost regimen, responses to the rLCMV-encoded Mtb antigens were further augmented, but protection was not significantly different from rLCMV or BCG vaccination alone. This work suggests that rLCMV may show utility for neonatal and/or adult vaccination efforts against pulmonary tuberculosis.  相似文献   
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A number of polysaccharides of the starch type, including maltodextrins and cyclodextrins and some other well-known polysaccharides have been oxidized by periodate/chlorite (two-step method) or hypochlorite (one-step method), yielding ring-opened polycarboxylates. The oxidation products from the starch type show by far the best calcium complexing properties and have potential application as phosphate substitutes in detergent formulations. A relatively sharp increase in calcium complexing ability is observed at a degree of polymerization of about ten, whereas just a slight further improvement occurs at higher degrees of polymerization. This phenomenon is explained by the formation of helix structures which contain efficient Ca(II) complexing sites. This idea is supported by 17O NMR measurements showing that oxidized starch type compounds with m > 10 behave as heptadentate ligands.  相似文献   
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Abstract

A short introduction on quantum thermodynamics is given and three new topics are discussed. (1) Maximal work extraction from a finite quantum system. The thermodynamic prediction fails and a new, general result is derived, the ‘ergotropy’. (2) In work extraction from two-temperature set-ups, the presence of correlations can push the effective efficiency beyond the Carnot bound. (3) In the presence of level crossing, non-slow changes may be more optimal than slow ones.  相似文献   
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Display of profiled sweep objects   总被引:1,自引:1,他引:0  
A class of free-form solids called profiled sweep objects is defined by four parametric curves: a 2D contour (cross-section), a 3D trajectory (spine), and two profile curves, which control the scaling of the contour as it moves along the trajectory. Subclasses of this are profiled prisms, which have a linear trajectory, and profiled generalized cylinders, which have an arbitrary 3D trajectory. First an exact definition of profiled sweep object, is presented and their relation with common sweep objects is described. Then a method is given for the construction of planar approximations of these objects that can be used for fast display generation. Finally, ray-tracing algorithms are given that directly use the exact definition for high-quality display.  相似文献   
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