Molecular evolutionary characterization of an Activator (Ac)-like transposable element sequence from pearl millet (Pennisetum glaucum) (Poaceae).

We present data on the evolution of the Ac/Ds family of transposable elements in select grasses (Poaceae). A defective Ac-like element was cloned from a DNA library of the grass Pennisetum glaucum (pearl millet) and its entire 4531 bp sequence has been determined. When the pearl millet Ac-like sequence is aligned with the maize Ac sequence, it is found that there is approximately 70% DNA similarity in the central region spanning most of maize Ac exon II and all of exon III.

Characterization of genes for an alternative nitrogenase in the cyanobacterium Anabaena variabilis.

Anabaena variabilis ATCC 29413 is a heterotrophic, nitrogen-fixing cyanobacterium that has been reported to fix nitrogen and reduce acetylene to ethane in the absence of molybdenum. DNA from this strain hybridized well at low stringency to the nitrogenase 2 (vnfDGK) genes of Azotobacter vinelandii. The hybridizing region was cloned from a lambda EMBL3 genomic library of A.

A defective visual pathway in children with reading disability.

Background: The possibility that reading disability in children is associated with visual problems is in dispute. We sought to test the existence of this association by using electrophysiologic techniques to measure the processing of visual information in the magnicellular and parvicellular visual pathways of the brain.

Methods: Visual evoked potentials were measured with scalp electrodes in children 8 to 11 years old who were normal readers and in those with reading disability.

Fears of normal and retarded children.

The developmental features of the fears of 112 nonretarded and 42 retarded children were examined. With development, the fears of nonretarded children became more closely aligned with real sources of threat that involve human agency and less fearful of imaginary things. The retarded children displayed patterns of fears similar to their mental-age peers rather than chronological peers and were more likely to deny being fearful than their nonretarded peers.

Initial comfort and surface wettability: a comparison between different contact lens materials.

A clinical investigation was performed to compare the initial comfort and surface wettability of the Novalens (Ocu-Tec), ENVISION (Polymer Technology Corporation) and D3X4 (Wesley-Jessen). Fifteen subjects were randomly fit with each one of these three lens materials. Initial comfort was significantly better with the D3X4 lens; no significant difference was found between the two rigid lens materials.

The impact of treatment of eye disease on optometric practice in Missouri.

This study attempts to determine the impact of the legal authorization to treat eye diseases on the practice of optometry in Missouri. Seventy-two percent of the therapeutic pharmaceutical agent (TPA) certified optometrists practicing in the state responded to a questionnaire in 1991. A majority of those responding prescribed every category of TPA except oral anti-histaminic agents.

Innovation in primary care: community health services in Mexico and the United States.

Providing adequate health care to a nation's citizens is a challenge in every country. Despite large differences in wealth, health care organization, and health politics, both Mexico and the United States undertook similar efforts to expand primary care to previously underserved populations during the past 30 years. This study analyzes common antecedents, contexts of change, elements of the innovations, problems with entrenched interests, and resources that have allowed both programs to survive in difficult environments.

Predicting psychiatric symptoms among homeless people.

Multiple regression was used to predict psychiatric symptoms among homeless people. The following variables were significant predictors of psychiatric symptoms: current life satisfaction, previous psychiatric hospitalization, the number of stressful life events, social support, problem drinking, and childhood unhappiness. The results are discussed in terms of their policy and practice implications, particularly the need for crisis intervention services and for dual-diagnosed clients.

Computer-specific spectacle lens design preference of presbyopic operators.

Twenty-nine presbyopic subjects who spent at least 20 hours a week at a video display terminal compared a progressive addition lens designed for this function, with another commonly prescribed task-specific lens. Each of the paired lens types was worn for 4 weeks and then compared directly for 1 week. A statistically significant (P < .

Factors influencing adjustment in the families of autistic children.

This study investigated factors influencing the adjustment of families of 49 autistic children (38 boys, 11 girls) to the stress of raising an autistic child. Analysis indicated that the severity of the child's disorder (stress), mother's social support (resources), and mother's perceived locus of control (perception) were significant factors in family adjustment. In addition, evidence suggested that agency affiliation also was an unexpected, yet important factor.

Model system using coliphage phi X174 for testing virus removal by air filters.

Short-term (15-min-duration) and long-term (5- to 6-day-duration) test procedures have been developed for determining the efficiency of the removal of bacteriophage phi X174 by air-sterilizing filters. These procedures were sensitive enough to measure a 10(8)-fold reduction in the number of bacteriophage. A filter commonly used in industrial air sterilizations (Domnick-Hunter Bio-X borosilicate glass) effected a 10(8)-fold removal of viable phage in both short-term and long-term tests.

The perceived duration of gratings.

Since visible persistence of grating patterns increases with spatial frequency, it is often inferred that the perceived duration of a grating is also longer at higher spatial frequencies. However, other work has demonstrated that the perceived onset of a grating is also delayed at higher spatial frequencies. Thus it is impossible to infer the subjective duration from the results of visible persistence studies alone.

Binding of phosphonate chelating agents and pyrophosphate to apotransferrin.

Difference ultraviolet spectroscopy has been used to monitor the binding of a series of phosphonate ligands to human apotransferrin. The ligands consist of pyrophosphate as well as the phosphonic acids (aminomethyl)phosphonic acid (AMPA), (hydroxymethyl)phosphonic acid (HMP), (phosphonomethyl)-iminodiacetic acid (PIDA), N,N-bis(phosphonomethyl)glycine (DPG), and nitrilotris(methylenephosphonic acid) (NTP). Equilibrium constants have been measured for the sequential binding of two ligands per molecule of apotransferrin.

The role of physical education in the development of active lifestyles.

If elementary physical education existed just to achieve "present" goals, especially regular exercise, the nature of the program would be clearer and the need for trained teachers less. It is the "future" goal that complicates the debate over the elementary program. It is the "future" goal that requires a broader range of experiences and a developmental approach.

Second-order factors of the MMPI item pool in a psychiatric sample.

Finn's (1986) two second-order MMPI factors, based on the factor scales of Johnson, Butcher, Null, and Johnson (1984), were examined in a psychiatric sample (N = 2,027) by a confirmatory factor analytic procedure. The two-factor model was rejected in the psychiatric sample, and a three-factor model was derived using exploratory factor analysis. An Anti-social factor was present in the current study, but not in that of Finn (1986).

Site-specific rate constants for iron removal from diferric transferrin by nitrilotris(methylenephosphonic acid) and pyrophosphate.

The kinetics of iron removal from human serum diferric transferrin by nitrilotris(methylenephosphonic acid) (NTP) and pyrophosphate (PPi) have been studied in 0.1 M, pH 7.4, N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonate buffer at 25 degrees C using urea/polyacrylamide gel electrophoresis.

Practice profile of University of Missouri-St. Louis optometry graduates.

The results of a survey of the University of Missouri-St. Louis School of Optometry graduates are presented. The practice mode selected and relocation throughout the country is examined for the school's first four graduating classes.

Homeless men and women: commonalities and a service gender gap.

Gender differences among homeless persons on a host of variables were examined. A stratified random sample of 248 homeless persons staying in shelters in St. Louis provided data for the study.

Electroretinograms and visual evoked potentials in long-term monocularly deprived cats.

The effects of long-term monocular lid-suture deprivation on visual-evoked cortical potentials (VEPs) and flash- and pattern-evoked electroretinograms (FERGs and PERGs, respectively) were assessed in the cat. VEPs were virtually eliminated when recorded with the deprived eye, indicating that the lid suture produced a severe amblyopia in that eye. In contrast, FERGs and PERGs were more similar for both deprived and nondeprived eyes and comparable to those recorded in normal animals.

Proton NMR relaxation in hydrogel contact lenses: correlation with in vivo lens dehydration data.

A study of hydrogel contact lenses was undertaken to determine whether NMR relaxation data can be used as a predictor for on-eye lens dehydration. Proton NMR relaxation times (T1 and T2), were determined for a series of contact lenses for which on-eye dehydration data were also available. NMR relaxation times were found to depend upon lens water content, but the dependence was not monotonic.

Increased scope of practice: a survey of Missouri doctors of optometry.

This study attempts to assess the effects on the Missouri optometric community resultant from the recent expansion in the scope of practice to include the management of ocular disease with pharmaceutical agents. A majority of those responding reported they felt comfortable in providing such services. They also reported an increase in income and patient retention.

The no-care zone: availability, accessibility, and acceptability in community-based long-term care.

Community-based care for chronic illness requires a continuum of services. This article identifies three aspects of the organization of long-term care that are important in maintaining a continuum: availability, accessibility, and acceptability. Each category is illustrated by data from Missouri to demonstrate potential problems in each of the three areas that can prevent the chronically ill from obtaining needed services.