Visual information

The visual information provided by radiography images is complex, considering of the great number of disruptive factors. Processed images ate characterized by three particular phenomena ... 

Dechsri, R, Jones, L. L., Heikkinen, H. W. (1997). Effeet of a laboratory manual design incorporating visual information-processing aids on student learning and attitudes. Journal of Research in Science Teaching, 34(9), 891-904. 

We need to transition from quasi-computerized methods, in which the different elements of the analytical process are treated as discrete, paper report tasks, to a comprehensive informatics approach, in which the entire data collection and analysis is considered as a single reusable, extensible, auditable, and reproducible system. Informatics can be defined as the science of storing, manipulating, analyzing, and visualizing information using computer systems. [3]... 

At its most fundamental level, the circadian cycle rests on the influence of so-called clock genes . These genes have been studied most extensively in insects but they have also been found in humans. Their protein products enter the cell nucleus and regulate their own transcription. This feedback process is linked to exposure to light and so it is not surprising that visual inputs are important for maintenance of circadian rhythms. However, it is not the reception of specific visual information, transmitted in the optic nerve to the lateral geniculate nucleus (LGN) and visual cortex (i.e. visual discrimination), that is responsible for the rhythm but the more simple, almost subconscious, reception of light. 

Geniculate nucleus The portion of the brain that processes visual information from the optic nerve and relays it to the cerebral cortex. 

Loke, W. H., The effects of caffeine and automaticity on a visual information processing task. Human- Psychopharmacology- Clinical-and-Experimental 7(6), 379-388, 1992. 

For a more detailed discussion of vision, including the transduction and processing of visual information, the reader is refered to Ref. 18, Chapter 3 and references therein. 

Named for the bones of the cranium under which they lie, the lobes are conspicuously defined by prominent sulci of the cortex, which have a relatively constant position in human brains. Each lobe is specialized for different activities (see Figure 6.3). Located in the anterior portions of the hemispheres, the frontal lobes are responsible for voluntary motor activity, speaking ability, and higher intellectual activities. The parietal lobes, which are posterior to the frontal lobes, process and integrate sensory information. The occipital lobes, located in the posterior-most aspects of the cerebrum, process visual information, and the temporal lobes, located laterally, process auditory information. 

A patient with a lesion in Wernicke s area is unable to understand any spoken or visual information. Furthermore, the patient s speech, while fluent, is unintelligible because of frequent errors in the choice of words. This condition is known as receptive aphasia. On the other hand, a patient with a lesion in Broca s area is able to understand spoken and written language but is unable to express his response in a normal manner. Speech in this patient is nonfluent and requires great effort because he cannot establish the proper motor command to articulate the desired words. This condition is known as expressive aphasia. 

Figure 58-1 An illustration of the use of scatter plots for gleaning visual information with respect to the correlation between variables X (abscissa) and Y (ordinate).

Visual Information Representation, Communication, and Image Processing, edited by Chang Wen Chen and Ya-Qin Zhang... 

It proves helpful to have the more frequently found isotopic distributions at hand. For some Cl, Bry and Cl Bry combinations these are tabulated in the Appendix. Tables are useful for the construction of isotopic patterns from building blocks . Nevertheless, as visual information is easier to compare with a plotted spectrum these patterns are also shown below (Fig. 3.3). In case of Cl and Br the peaks are always separated from each other by 2 u, i.e., the isotopic peaks are located at X+2, 4, 6 and so on. 

FTND Fagerstrom test for nicotine dependence RVIP rapid visual information processing NA not applicable DLPFC dorsal lateral prefrontal cortex Data shown for FTND and pack-years are means for the smokers Pack-years = packs of cigarettes smoked per day x number of years smoked... 

Lawrence and colleagues (2002) explored the neural substrates of nicotine effects on sustained attention using the rapid visual information processing (RVIP) task. Smokers (n = 15) received either placebo or 21-mg transdermal nicotine patch prior to testing. Matched nonsmokers (n = 14) were tested under similar conditions, but did not receive a nicotine patch. Relative to the placebo condition, the smokers in the nicotine condition demonstrated improved task performance and increased neural activity in the parietal and occipital cortices, the thalamus and caudate, and decreased activity in left frontal, anterior and posterior cingulate, insula, and left parahippocampal regions (see Fig. 3). As noted by the authors, previous studies... 

Fig. 3 Activation difference between the rapid visual information processing (RVIP) and control tasks in smokers after administration of placebo and nicotine patches. The graphs show the percent change in activation (from baseline) during performance of each task in smokers in the two drug conditions. After receiving nicotine, smokers demonstrated better task performance and more task-related activity in the parietal (A and B) and occipital (C and D) cortices compared to the parallel measures after they received placebo (Kumari et al. 2003)...

Lawrence et al, (2002) 15 Smokers fMRI/rapid visual information-processing 21-mg nic vs, placebo patch t Parietal and occipital ctx, thal, caudate... 

It is difficult to evaluate the shape of such dendritic particles experimentally. However, some insight can be gained by atomic force microscopy (AFM) and transmission electron microscopy experiments (TEM). AFM experiments can give information about the overall size of the dendrimers, as shown by De Schryver [43], by spincoating very dilute solutions of dendrimers like 30 on mica, then visualizing single dendrimers. Their height measured in this manner corresponds very well to the diameters calculated by molecular mechanics simulations. First results from TEM measurements also confirm the expected dimensions [44]. Unfortunately, due to resolution limits, up to now direct visual information could not be obtained about the shape of the dendrimers. 

Reserpine and iproniazid research led to the monoamine hypothesis of depression. This hypothesis proposed that a reduction in the monoamine neurotransmitters caused depression. As described in the sidebar on pages 82-83, only a small number of neurons use serotonin as a neurotransmitter, but these cells project to widespread regions of the brain. The same holds true for norepinephrine and dopamine. Although not widely used in the nervous system, these neurotransmitters are apparently involved in networks of neurons that greatly influence a person s mood. Synaptic transmission between neurons in other areas of the brain—such as neurons that process visual information, for instance—often carry specific messages, such as the presence of an object at a certain point in the person s visual field. In contrast, the monoamine neurotransmitters underlie information processing of a more general nature, some of which correlates with mood. 

PCA is a useful tool not only for visualizing information it can also be employed as a strategy for feature reduction and noise reduction, as indicated in Section Vl.C. 

We briefly discussed the origin and structure of liquid crystals in Section 4.13. The last decade has witnessed a surge of interest in liquid crystals because of their applications in display devices (devices that convert an electrical signal into visual information). The design of liquid crystal (LC) devices relies on the relation between the molecular structure and the phase behaviour (relative smectic-nematic tendency, NI etc.) as well as the physical properties of the liquid crystals (Chandrasekhar, 1994). 

Researchers have been dogged by the inability to delineate between myoactivity and neuroactivity, mainly because the isolation of individual tissues by dissection is extremely difficult. This obstruction precipitated the development of methods to generate dispersed muscle fibres, and these preparations provided the first visual information on individual muscle fibres and/or muscle fibre bundles three morphologically distinct fibre types were recorded from Schistosoma mansoni, frayed, spindle-shaped and crescent-shaped fibres (Day et al., 1993). Although the location of all three fibre types within the worm is not clear, it has been suggested that the frayed fibres originate from the longitudinal muscle layer. 

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