抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

Co-Planar Stereotaxic Atlas of the Human Brain—3-Dimensional Proportional System: An Approach to Cerebral Imaging, J. Talairach, P. Tournoux. Georg Thieme Verlag, New York (1988), 122 pp., 130 figs. DM 268

I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

Principles of Neural Science

Brains, it has recently been argued, are essentially prediction machines. They are bundles of cells that support perception and action by constantly attempting to match incoming sensory inputs with top-down expectations or predictions. This is achieved using a hierarchical generative model that aims to minimize prediction error within a bidirectional cascade of cortical processing. Such accounts offer a unifying model of perception and action, illuminate the functional role of attention, and may neatly capture the special contribution of cortical processing to adaptive success. This target article critically examines this "hierarchical prediction machine" approach, concluding that it offers the best clue yet to the shape of a unified science of mind and action. Sections 1 and 2 lay out the key elements and implications of the approach. Section 3 explores a variety of pitfalls and challenges, spanning the evidential, the methodological, and the more properly conceptual. The paper ends (sections 4 and 5) by asking how such approaches might impact our more general vision of mind, experience, and agency.

/pdf/whatever-next-predictive-brains-situated-agents-and-the-epj56cs868.pdf

Whatever next? Predictive brains, situated agents, and the future of cognitive science

Lasik is a common surgery for treating anisometropia. In this study, we asked a specific question: what’s the effect of Lasik surgery on anisometropes’ sensory eye dominance
 ? Fifteen myopic anisometropes (mean age: 23 ± 6.9 years old; 6 females) participated in our experiment. We quantitatively measured participants’ sensory eye dominance before and after the Lasik surgery using a binocular phase combination paradigm. We found no significant change of sensory eye dominance within 16 weeks (measured between 8 to 96 days, for one or two repetitions) after the surgery (t(14) = −1.44, p = 0.17). A further following on eight patients showed that patients’ two eyes were much more balanced at 16 weeks or more (measured one or two times between 112 to 408 days) after the surgery (t(7) = −3.79, p = 0.007). Our results suggest that the benefit of Lasik surgery on anisometropes’ sensory eye dominance is not immediate, a long-term ‘adaptation’ period (16 weeks or more) is necessary to enable the surgery to be truly effective.

/pdf/the-effect-of-lasik-surgery-on-myopic-anisometropes-sensory-3q5ftn5kcr.pdf

The effect of Lasik surgery on myopic anisometropes’ sensory eye dominance

http://mvr.mcgill.ca/Kathy/PDF-85-94/Hess-Mullen-Nordby-1992.pdf

Mutual rod-cone suppression within the central visual field.

We studied the binocular organization of motion opponency and its relationship to contrast gain control. Luminance contrast thresholds for discriminating direction of motion were measured for drifting Gabor patterns (target) presented on counterphase flickering Gabor patterns (pedestal). There were four presentation conditions: binocular, monocular, dichoptic, and halfbinocular. For the half-binocular presentation, the target was presented to one eye while pedestals were presented to both eyes. In addition, to test for motion opponency, we studied two increment and decrement conditions, in which the target increased contrast for one direction of movement but decreased it for the opposite moving component of the pedestal. Threshold versus pedestal contrast functions showed a dipper shape, and there was a strong interaction between pedestal contrast and test condition. Binocular thresholds were lower than monocular thresholds but only at low pedestal contrasts. Monocular and half-binocular thresholds were similar at low pedestal contrasts, but half-binocular thresholds became higher and closer to dichoptic thresholds as pedestal contrast increased. Adding the decremental target reduced thresholds by a factor of two or more-a strong sign of opponency- when the decrement was in the same eye as the increment or the opposite eye. We compared several computational models fitted to the data. Converging evidence from the present and previous studies (Gorea, Conway, & Blake, 2001) suggests that motion opponency is most likely to be monocular, occurring before direction-specific binocular summation and before divisive, binocular gain control.

Direction discrimination thresholds in binocular, monocular, and dichoptic viewing: motion opponency and contrast gain control

Orientation-modulated stimuli are thought to be processed via a two-stage process, the first stage involving the detection of the carrier by mechanisms in striate cortex and the second stage involving the detection of the modulation by way of integration of carrier-based information by mechanisms in extra-striate cortex. Much is known about the spatial properties of the channels underlying carrier detection but less is known about the properties of the channels involved in modulation detection. Using a discrimination at detection paradigm, we show that the mechanisms underlying modulation detection are tuned for envelope spatial frequency and orientation. The tuning of these channels is not substantially different from that previously described for carrier mechanisms, namely 1–2 octaves for spatial frequency and 30° for orientation. For orientation, these stimuli exhibit an oblique effect that is dependent on absolute carrier orientation, suggesting facilitative interactions between first- and second-stage processes.

Properties of spatial channels underlying the detection of orientation-modulations.

http://mvr.mcgill.ca/Kathy/PDF-10-14/Brown-Feigl-Gole-Mullen-Hess-2013.pdf

Robert F. Hess

Papers

The effect of Lasik surgery on myopic anisometropes’ sensory eye dominance

Mutual rod-cone suppression within the central visual field.

Direction discrimination thresholds in binocular, monocular, and dichoptic viewing: motion opponency and contrast gain control

Properties of spatial channels underlying the detection of orientation-modulations.

Assessment of neuroretinal function in a group of functional amblyopes with documented LGN deficits