Pushing the limits of artificial vision

The field of neural prostheses has made significant strides toward restoring damaged or lost nervous system function for millions of people. These advances have led to the development of selective electrical interfaces that communicate directly with nerve cells to modulate neural processes rationally. The first neural prosthesis developed was the cardiac pacemaker, which has become pervasive in society. The pacemaker also provides the promise that such an approach can address higher order neural dysfunctions. Technologies borrowed from the semiconductor industry have allowed researchers to micro fabricate devices with active elements on the length scale of nerve cells. This size capability has led to the development of the cochlear implant, which has restored hearing in thousands of deaf patients. Restoring more complex sensory functions, such is vision, provides greater engineering challenges, but achieving them is within our grasp. Current approaches to achieving artificial vision are discussed, along with strategies being used to push the capability limits of these prostheses even further.     

Equipment for the investigation and metrological certification of petroleum density meters

Translated from Izmeritel'naya Tekhnika, No. 12, pp. 28–29, December, 1990.     

Puerto Rican intellectuals in New York: Some intragroup and intergroup contrasts.

A factor analysis of coded interview data on 20 Puerto Rican intellectuals in the New York City area yielded 5 item-factors (R) and 2 person-factors (Q). The R factors dealt with Spanish language dominance, ideological language maintenance, Puerto Rican cultural emphases, American awareness, and sociolinguistic sophistication. The Q groups differed meaningfully and consistently on these 5 factors and on demographic background variables, particularly with respect to ideological vs. behavioral Puerto Rican culture and language maintenance. Intellectuals as a group were found to differ greatly and systematically from ordinary Puerto Rican males in having more ideological positions with respect to Puerto Rican culture and Spanish language maintenance in New York. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Additions to "Guides to Psychological Literature"

The author opines on the value of Dr. Latham's "Guides to Psychological Literature" (Amer. Psychologist, 1954, 9, 21-28) and states that every effort to complete his listings and to keep them up to date should be made. The author adds two less well-known guides to certain aspects of psychological literature, which he has found to be of some value. The two are special indexes and abstract journals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fundus flavimaculatus. A clinical classification

Various stages of fundus flavimaculatus seen ophthalmoscopically were correlated with findings on electrophysiologic and psychophysical tests. A new classification of fundus flavimaculatus into stages recognizes the nuances in genetic expression and their correlation with findings on retinal function testing.     

Familial supravalvular aortic stenosis. Report of a large family and review of the literature

Familial supravalvular aortic stenosis has been recognized as a distinct syndrome. A large family with five proven cases and a review of the literature on familial supravalvular aortic stenosis are presented. The diagnosis was substantiated in all 63 cases by cardiac catheterization, surgery, or postmortem examination.     

The effect of undernutrition on the development of myelin in the rat central nervous system

Newborn rats were segregated into litters of 6 and 22 pups. Undernourished groups were maintained for 21 and 53 days at which time a portion of each group was sacrificed and the remainder refed until 121 days. The amount of myelin isolated from the central nervous system was decreased in nutritionally deprived animals but there was little change in its chemical composition or intereference in the normal chemical maturation of the membrane. The only consistent change was a reduction in phosphatidyl ethanolamine plasmalogen. This deficit tended to be corrected by nutritional rehabilitation and was most complete in those animals refed ad lib. diets for the longest time periods prior to sacrifice. The relatively normal chemical composition of myelin obtained from undernourished animals differs from changes described in myelin membranes isolated from patients with destructive or degenerative diseases of the nervous system. This seems to be further evidence that the reduction in myelination in undernutrition is a result of decreased synthesis of the membrane.