Saccade Automation

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 141-141
Author(s):  
V A Filin

The comparative analysis of basic saccade characteristics (interval, amplitude, and coefficient of asymmetry) has shown considerable similarities in adults and first-year babies. Distribution curves of intersaccadic intervals under different test conditions all have only one maximum in the range of about 0.4 s, and in all cases the most frequently met intersaccadic intervals (0.1 – 1.0) comprised comparable proportions of all (71.5% – 90.5%). The concept of saccade automation was formulated on the basis of these data (Filin and Filina, 1989 Zhurnal Vysshei Nervnoi Deyatelnosti29 603 – 607). In our opinion saccade automation is the basic law of saccadic activity, and all diversity of eye-movement activity takes place against the background of saccade automation. Microsaccades and macrosaccades, nystagmus, and rapid eye movements during sleep may be seen as special cases of saccade automation. Saccade automation is conditioned by the activity of brain structures with pacemaker function. Thus saccades are driven at one basic frequency, which is modulated by afferent influences from the retina of vestibular apparatus, proprioreceptors of eye and neck muscles, and efferent signals (forehead and occipital sections of cerebral cortex, cerebellum). At the same time, only one parameter is modulated at one particular moment, for example saccade amplitude in which case interval and orientation are given in a ready form. Saccade automation has a great functional importance. It increases the scanned area tenfold, it provides compensation of defects in the sensors and the impellent eye apparatus and for the deletion of consecutive images, maintaining the continuity of visual perception. Moving the image on the retina increases the information of the visual channel.


2021 ◽  
Vol 10 (4) ◽  
pp. 861
Author(s):  
Mijna Hadders-Algra

This review discusses early diagnostics and early intervention in developmental disorders in the light of brain development. The best instruments for early detection of cerebral palsy (CP) with or without intellectual disability are neonatal magnetic resonance imaging, general movements assessment at 2–4 months and from 2–4 months onwards, the Hammersmith Infant Neurological Examination and Standardized Infant NeuroDevelopmental Assessment. Early detection of autism spectrum disorders (ASD) is difficult; its first signs emerge at the end of the first year. Prediction with the Modified Checklist for Autism in Toddlers and Infant Toddler Checklist is possible to some extent and improves during the second year, especially in children at familial risk of ASD. Thus, prediction improves substantially when transient brain structures have been replaced by permanent circuitries. At around 3 months the cortical subplate has dissolved in primary motor and sensory cortices; around 12 months the cortical subplate in prefrontal and parieto-temporal cortices and cerebellar external granular layer have disappeared. This review stresses that families are pivotal in early intervention. It summarizes evidence on the effectiveness of early intervention in medically fragile neonates, infants at low to moderate risk, infants with or at high risk of CP and with or at high risk of ASD.



1998 ◽  
Vol 14 (6) ◽  
pp. 795-798
Author(s):  
Oliver B. Linton

This book is a modern introduction to measure theoretic probability and statistical inference well targeted for graduate students in econometrics at top institutions. It would make an excellent textbook for first year graduate students who intend to specialize in econometrics or who have an advanced mathematical background, and it would also be a useful part of any graduate econometrics course. It is concise and intensely focused on the key conceptual points, thus counteracting the tendency toward long-windedness apparent in some recent econometric texts. Nevertheless, it provides many valuable insights into difficult material. In particular, the discussions of sigma fields and conditional expectation given a sigma field are very helpful. The coverage of multivariate concepts alongside univariate ones is particularly useful to econometricians and something that is missing from most comparable statistical texts. The author has a mature attitude to proof, providing complete and illuminating proofs of some results but making liberal use of simplifications provided by special cases, for example in Theorems 4.1 and 4.5 and Section 5.2.2, to shorten and focus the arguments. The proofs themselves are very clear and well presented. Carefully chosen diagrams are given throughout the book that nicely illustrate many of the key concepts. In addition, each chapter contains a long list of problems of varying complexity, which will be useful to instructors.



2003 ◽  
Vol 2003 (1) ◽  
pp. 429-434
Author(s):  
Merv Fingas ◽  
Ben Fieldhouse ◽  
Jordan Noonan ◽  
Pat Lambert ◽  
James Lane ◽  
...  

ABSTRACT This paper summarizes studies to determine the stability of water-in-oil emulsions in the OHMSETT tank facility and comparison with laboratory results. The OHMSETT tests were in four series. The tests were one week each in the first year and two weeks each in the second year. The first and second series consisted of 12 experiments each on 6 oils. The third series consisted of testing 9 oils through a series of 16 experiments. In the fourth set of tests, 8 oils were used in 16 experiments. Several of the experiments consisted of leaving the oils for longer periods of time. The rheological properties of the oils were measured and compared to the same oils undergoing emulsification in the laboratory. The oils and water-in-oil states produced were found to have analogous properties between the laboratory and the OHMSETT facility. Comparison of time and work factors showed that the energy in the two test conditions was similar. These tests also provide information on the kinetics and energy levels necessary to form emulsions, which is useful to oil spill modellers. These studies have confirmed previous laboratory studies that show that the stability of emulsions can be grouped into four categories: stable, unstable, meso-stable, and entrained. Water can reside in oil as ‘entrained water', in which larger droplets of water are temporarily suspended by viscous forces. These emulsions and mixtures have been distinguished by physical measures as well as visual differences.



Prawo ◽  
2021 ◽  
Vol 332 ◽  
pp. 55-67
Author(s):  
Paweł Wiązek

Deputies against the problem of judicial law reform in the first year of the session of the Grand Sejm, in the light of the parliamentary diaries by Jan Paweł Łuszczewski and Antoni Siarczyński In 1788, in the face of the deepening crisis of the state and the real threat of losing sovereign existence, an extraordinary Sejm was convened in the Polish-Lithuanian Commonwealth, whose decisions and reforms were to save the independence of the state, while at the same time thoroughly modernising it. This congregation went down in history as the Four-Year or Grand Sejm, which many saw and still see as an appreciation of its great work. One of the actions taken was a profound reform of judicial law, the anachronistic nature of which was a significant cause of the country’s weakness and the problems of its citizens. Ultimately, however, somewhat paradoxically, the glorious and greatest achievement of the assembly — adopting a constitution — resulted in a civil war, a military conflict with a powerful neighbor — Tsarist Russia, and the liquidation of the Polish state. The aforementioned basic law devoted one of its articles to the judiciary, obliging it to create a new legal code. However, this commitment was never fulfilled. The question of why this happened is still open. The attempt to answer this question is part of the fundamental dispute over the causes of the collapse and liquidation of the state, a discourse that has provoked passionate polemics for decades. The author made an attempt to take his own position on this issue, based on the results of the undertaken research. He conducted a thorough analysis of exceptionally valuable sources such as the Sejm diaries, which constitute a record of the deputies’ speeches at the forum of the plenary Sejm sessions, similar to modern meeting records. In the actions and attitudes of the nation’s representatives, at the moment of his greatest attempt, he tried to find the key to resolving the dispute.   Die Abgeordneten angesichts der Frage der Reform des Gerichtsrechts im ersten Tagungsjahr des Großen Sejm anhand der Sejm-Protokollbücher von Jan Paweł Łuszczewski und Antoni Siarczyński In Anbetracht der sich vertiefenden Krise des Staates und der realen Gefahr, die Souveränität zu verlieren, wurde im Jahr 1788 in der Republik beider Nationen der außerordentliche Sejm einberufen, dessen Entscheidungen und Reformen die Unabhängigkeit des Staates retten und ihn dabei tief modernisieren sollten. Diese Versammlung schrieb Geschichte als der Vierjährige oder Große Sejm, worin viele die Anerkennung der Größe seiner Werke sahen und sehen. Eine der eingeschlagenen Richtungen seiner Tätigkeit war die Reform des Gerichtsrechts, dessen veralteter Charakter einen wichtigen Grund für die Schwächen des Staates und die Probleme seiner Bürger darstellte. Letztendlich jedoch, ein wenig paradox, führte der lobenswerte und wichtigste Erfolg der Versammlung — die Verabschiedung der Verfassung — zum Ausbruch des Hauskrieges, zum militärischen Konflikt mit dem großen Nachbar — Zarenrussland und zur Auflösung des Staates. Ein der Artikel dieses Grundgesetzes wurde der rechtsprechenden Gewalt gewidmet und verpflichtete dazu, ein neues Gesetzbuch zu verfassen. Dieser Verpflichtung ist jedoch nie nachgekom-men worden. Offen bleibt immer noch die Frage — warum. Der Versuch, sie zu beantworten stellt einen Bestandteil des fundamentalen Streites um die Gründe des Zusammenbruchs und der Auflösung des Staates dar, einer Diskussion, die bereits über Jahrzehnte zur bewegten Polemik führt. Der Autor versuchte, anhand der geführten Forschungen, eigene Stellung dazu zu nehmen. Eingehende und gründliche Analyse der besonders wertvollen Quellen — der Sejm-Protokollbücher, der Niederschrift der Abgeordnetenauftritte während der Plenarsitzungen des Sejm, die den gegenwärtigen Stenogrammen ähneln, machte er zum Wesen dieser Forschungen. Im Tun und Haltung der Vertreter des Volkes zum Zeitpunkt der größten Probe versuchte er, den Schlüssel zur Entscheidung des Streites zu finden.



PEDIATRICS ◽  
1949 ◽  
Vol 3 (2) ◽  
pp. 195-200
Author(s):  
KATHERINE E. ROBERTS ◽  
C. ANDERSON ALDRICH

WHEN a child living in Rochester reaches the age of 2½ years a letter is sent to his mother asking her to bring the child in to the office of the Rochester Child Health Institute for a check-up. The letter states that the child will be given a developmental test and instructs the mother to tell her child that he is coming to play with some toys. Both mother and child are thus prepared for a friendly visit and an effort is made to have it be a happy experience for everybody concerned. This test is the first standardized one that is given any of our children, since the age of 2½ years is about the earliest age at which the Revised Stanford-Binet test can be used satisfactorily. The visit at this age is the first routine contact that the parent and child have with the psychologists on the Institute staff, although earlier conferences may be arranged in special cases. We hope by offering a routine psychologic service to all the children in the community that parents will learn that it is just as desirable, helpful and normal for their children to have a psychologic check-up as it is to have a physical check-up. We believe that our results will show that most Rochester parents are developing this attitude. This program was started in July 1946 when the babies born in 1944 began reaching the age of 21/2 years. By July 1948, we will have had two years of experience with this program. From the point of view of cooperation, the results are heartening. The first year, 86% of the children on our list were brought in for a test, and on all but 5% we were able to carry out a fairly satisfactory test. During the first nine months of the second year 92% of the children came and a satisfactory test was completed on all but 4%. This acceptance of the psychologic part of the program is undoubtedly related to the fact that parents have had 2½ years of satisfactory contact with the Institute through the prenatal, neonatal and child health clinics and they think any service offered them is likely to be helpful. Another factor of importance is the routine nature of the test. Everyone in town who has a 2½-year-old—not just parents with dull children, problem children or atypical children of some kind—is invited to come. We find now that, if for some reason we miss a child in this age range, parents call up and ask when their child can come. We are probably justified in our belief that parents who come like the service and tell their friends about it.



Author(s):  
M. Isaacson ◽  
M.L. Collins ◽  
M. Listvan

Over the past five years it has become evident that radiation damage provides the fundamental limit to the study of blomolecular structure by electron microscopy. In some special cases structural determinations at very low doses can be achieved through superposition techniques to study periodic (Unwin & Henderson, 1975) and nonperiodic (Saxton & Frank, 1977) specimens. In addition, protection methods such as glucose embedding (Unwin & Henderson, 1975) and maintenance of specimen hydration at low temperatures (Taylor & Glaeser, 1976) have also shown promise. Despite these successes, the basic nature of radiation damage in the electron microscope is far from clear. In general we cannot predict exactly how different structures will behave during electron Irradiation at high dose rates. Moreover, with the rapid rise of analytical electron microscopy over the last few years, nvicroscopists are becoming concerned with questions of compositional as well as structural integrity. It is important to measure changes in elemental composition arising from atom migration in or loss from the specimen as a result of electron bombardment.



Author(s):  
Werner J. Niklowitz

After intoxication of rabbits with certain substances such as convulsant agents (3-acetylpyridine), centrally acting drugs (reserpine), or toxic metal compounds (tetraethyl lead) a significant observation by phase microscope is the loss of contrast of the hippocampal mossy fiber layer. It has been suggested that this alteration, as well as changes seen with the electron microscope in the hippocampal mossy fiber boutons, may be related to a loss of neurotransmitters. The purpose of these experiments was to apply the OsO4-zinc-iodide staining technique to the study of these structural changes since it has been suggested that OsO4-zinc-iodide stain reacts with neurotransmitters (acetylcholine, catecholamines).Domestic New Zealand rabbits (2.5 to 3 kg) were used. Hippocampal tissue was removed from normal and experimental animals treated with 3-acetylpyridine (antimetabolite of nicotinamide), reserpine (anti- hypertensive/tranquilizer), or iproniazid (antidepressant/monamine oxidase inhibitor). After fixation in glutaraldehyde hippocampal tissue was treated with OsO4-zinc-iodide stain and further processed for phase and electron microscope studies.



Author(s):  
H. Bethge

Besides the atomic surface structure, diverging in special cases with respect to the bulk structure, the real structure of a surface Is determined by the step structure. Using the decoration technique /1/ it is possible to image step structures having step heights down to a single lattice plane distance electron-microscopically. For a number of problems the knowledge of the monatomic step structures is important, because numerous problems of surface physics are directly connected with processes taking place at these steps, e.g. crystal growth or evaporation, sorption and nucleatlon as initial stage of overgrowth of thin films.To demonstrate the decoration technique by means of evaporation of heavy metals Fig. 1 from our former investigations shows the monatomic step structure of an evaporated NaCI crystal. of special Importance Is the detection of the movement of steps during the growth or evaporation of a crystal. From the velocity of a step fundamental quantities for the molecular processes can be determined, e.g. the mean free diffusion path of molecules.



Author(s):  
J.M. Robinson ◽  
J.M Oliver

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.



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