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F B Martin

Publications and source records attributed to F B Martin.

16 recordsLinked to original sources

Nature and incidence of self-reported adolescent work injury in Minnesota.

Most studies of adolescent work-related injury that have been published to date have been confined to administratively collected data available through state or national departments of labor and industry and/or occupational safety and health administrations. These data do not contain information on the severity or the sequelae of injuries. In addition, estimates of incidence may be biased due to inadequate data on the nature, amount, and seasonal variability of work done by adolescent workers. The present study is a cross-sectional survey of work and work injuries of 3,051 10th through 12th grade students from 39 high schools throughout Minnesota. Injury was defined as an event which caused any of the following: loss of consciousness, seeking medical care, and/or restricting normal activities for at least 1 day. The average hours of work per week during the summer and during the school year were 30 (95% Confidence Interval [CI] = 27, 33) and 16 (95% CI = 15, 17), respectively. There was no difference in hours worked between ethnic minorities and white students. The rate of reportable injuries was 12 per 100,000 hr worked (95% CI = 7, 18) for rural and 13 per 100,000 hr worked (95% CI = 7, 28) for urban females, 16 (95% CI = 9, 22) per 100,000 hr for urban males, and 20 (95% CI = 12, 28) per 100,000 hr for rural males. Ongoing medical problems were reported by 26% of the injured workers. Previous estimates of work-related injury to adolescents may have been low. More study is required to clearly define the incidence of injury and risk factors for these injuries.

Accidents, Occupational

Characteristics of adolescent work injuries reported to the Minnesota Department of Labor and Industry.

OBJECTIVES: The purpose of the study was to provide descriptive data and incidence data on adolescent work-related injuries and to determine whether such injuries are underreported to the Minnesota Department of Labor and Industry. METHODS: The study consisted of a 1-year survey of 534 adolescent work-related injuries reported to the Department of Labor and Industry and a cross-sectional survey of 3312 public high school students from throughout Minnesota. The high school survey used an abbreviated questionnaire with a subset of items from the Department of Labor and Industry survey. RESULTS: Ninety-six percent of the injuries were strains and sprains, cuts and lacerations, burns, bruises and contusions, and fractures. There were 11 hospitalizations; 4 were for burns that occurred during work in restaurants. Eighty workers (15%) reported permanent impairment as a result of their injuries. It was estimated that there were 2268 reportable injuries to working adolescents in Minnesota during the study year. CONCLUSIONS: The most common serious injuries were injuries to the lower back and burns. The demographic characteristics of adolescents whose injuries were reported to the Department of Labor and Industry were similar to those of injured adolescent workers identified through the high school survey. The results suggest that there is substantial underreporting of adolescent work injuries.

Accidents, Occupational

Specialized binary vector for plant transformation: expression of the Arabidopsis thaliana AHAS gene in Nicotiana tabacum.

We constructed a cosmid vector, pOCA18, designed for transferring plant genomic libraries from Agrobacterium tumefaciens to plants. Clones from a genomic library of Arabidopsis thaliana DNA in pOCA 18 were propagated stably in both Escherichia coli and A. tumefaciens. Clones from the pOCA18 A. thaliana library were used to construct transgenic Nicotiana tabacum plants; the DNA inserts were transferred intact in 10 out of 16 transgenic N. tabacum plants examined but were partially deleted in six others. Transgenic N. tabacum plants constructed with a mutant A. thaliana acetohydroxy acid synthase gene (from the pOCA18 library) that encodes an enzyme resistant to the herbicide chlorsulfuron were resistant to chlorsulfuron. A statistical analysis indicated that if the A. thaliana library contains 10(7) members and if 10(7) A. tumefaciens transconjugants containing the library were used to transform plant cells, then 2 x 10(4) transformed plant cells must be generated to have a 95% probability of constructing a transgenic plant carrying a specific DNA sequence from the A. thaliana library.

Cloning, Molecular

Epidemiologic study of Holstein dairy cow performance and reproduction near a high-voltage direct-current powerline.

The development and operation of a high-voltage direct-current (HVDC) transmission line in rural Minnesota generated public concern over potential adverse effects to nearby residents and their livestock. Electrical environmental parameters near an HVDC line decline rapidly with distance, but effects on ambient space charge have been detected out to 1 mile. Previous studies of powerline effects on livestock have involved the more common alternating-current (HVAC) lines, which create a different electrical environment. To identify potential adverse effects of HVDC line operation on livestock, case-control and cohort study methods were used to examine various indices of Holstein performance in relation to distance from the line and the onset of line operation. It was believed that these indices would reflect changes in physiologic function or overt health effects that might arise from the HVDC environment. High-quality performance data from existing Dairy Herd Improvement Association (DHIA) records were obtained for 97% of qualifying herds located within 10 miles of the line. The large number of animals and years of observation provided high statistical power to detect even small systematic changes in performance. No significant differences in milk production or reproductive capacity were associated with presumed exposure to the HVDC environment. The absence of measurable effects in a large "sentinel" animal population may have implications for the assessment of human health risks related to HVDC transmission lines.

Abortion, Veterinary

Enterobacteriaceae and Aeromonas hydrophila in Minnesota frogs and tadpoles (Rana pipiens).

In 222 Rana pipiens frogs and 34 tadpoles captured in and near Minnesota, Aeromonas hydrophila and 29 species of Enterobacteriaceae, including yersinia enterocolitica and Salmonella arizonae, were isolated from intestines. The prevalence of members of the family Enterobacteriaceae was lowest in frogs captured in early spring and highest in frogs captured in late summer.

Aeromonas

Effect of inspired air heat and humidification on anesthetic-induced hypothermia in dogs.

Dogs were evaluated for efficacy of inspired air heating and humidification in maintenance of body temperature during general anesthesia. Three separate trials were conducted: (i) a control group without thermal support (n = 5), (ii) a group supported only by a heated humidifier device placed in the inspiratory limb of an anesthesia circle delivery system (n = 7), and (iii) a group supported by combination of inspired air humidification and recirculating water blanket (n = 7). A significant difference (P greater than 0.4) was not noticed in temperature changes between control and humidifier-supported groups. A significant advantage (P less than 0.05) was noticed between the combined support and the humidifier or control groups. Seemingly, during general anesthesia, use of combined thermal support is significantly better than airway humidification for maintenance of normothermia in the dog.

Air

Porcine stress syndrome and postmortem muscle characteristics of two purebreds and three specific terminal crosses.

The incidence of Porcine Stress Syndrome (PSS), determined by halothane screening, and parameters of muscle quality and carcass leanness were studied in 108 pigs from a larger population of 658 pigs of Pietrain (P), Minnesota No. 1 (M), Hampshire (H) x (P x M), Yorkshire (Y) X (P X M) and P X (P X M) breeding. The larger population was also surveyed by the halothane screening procedure for incidence of PSS, and growth rate was measured. At 6 to 14 weeks of age, pigs were classified as PSS if they exhibited muscle rigidity within 5 min after the commencement of anesthetization with 3% halothane in oxygen. The incidences noted for the larger population were: H x (P x M) and Minnesota No. 1, 0%; Pietrain, 88%; Y x (P x M), 3%, and P x (P x M), 17%. Results demonstrated that the H x (P x M) group displayed excellent carcass meatiness combined with acceptable meat quality and freedom from PSS.

Animals

Aeromonas hydrophila in wild-caught frogs and tadpoles (Rana pipiens) in Minnesota.

Frogs and tadpoles were captured at 14 sites in and near Minnesota during 1978-79 and nearly all appeared healthy. Aeromonas hydrophila was isolated from 94 of 294 (32%) juvenile and adult frogs and from 66 of 104 (63%) tadpoles. Of the isolates from frogs and tadpoles respectively, 68% and 47% were from the intestine only, 12% and 32% were from the intestine and the other sites, and 20% and 21% were from extraintestinal sites only. Isolations were more frequent from frogs collected in March-June than in August-November. Evidence was not found that disease due to Aeromonas hydrophila was a primary cause of declining Rana pipiens populations in Minnesota.

Aeromonas

Reduced prevalence of the Lucké renal adenocarcinoma in populations of Rana pipiens in Minnesota.

Northern leopard frogs (Rana pipiens) afflicted with the Lucké renal adenocarcinoma virtually disappeared from Minnesota in the autumn of 1977. Frogs from four sites in Minnesota counties (Polk, Otter Tail, Kandiyohi, and Scott) with a previously high prevalence of Lucké renal tumor were studied. In the past decade, prevalence averaged 4.2% in 29 collections (total, 1,870 frogs). No tumors were detected in 685 frogs autopsied in the autumn of 1977 by the method of previous studies. Frog collections, each comprised of 20 or more individuals, were compared for the presence or absence of tumor-bearing frogs. Significantly fewer collections contained tumor-bearing frogs in the autumn of 1977 than did collections of previous years.

Adenocarcinoma

Characterization of the antigenic determinants of cholera toxin subunits.

The antigenic specificity of purified preparations of A subunit, B subunit, alpha chain, and gamma chain of cholera toxin was studied by double immunodiffusion and radioimmunoassay with antisera produced in rabbits and mice. Rabbits immunized with A subunit produced serum antibodies which were capable of binding radiolabeled A subunit, alpha chain, and B subunit. Rabbits immunized with alpha chain produced serum antibodies that would bind radiolabeled alpha chain and A subunit. Rabbits immunized with the B subunit produced serum antibodies monospecific for the B subunit. The gamma chain did not elicit measurable antibodies in rabbits or mice as evidenced by radioimmunoassay or double immunodiffusion. A sensitive competitive radioimmunoassay was developed in which the B subunit could inhibit binding of radiolabeled A subunit and alpha chain with either antisera prepared against A subunit or alpha chain. Neither the A subunit nor the alpha chain could inhibit binding of B subunit with the antiserum prepared against B subunit. In addition, selected elution fractions obtained during A- and B-subunit purification were used to immunize groups of mice. Mice responded to immunization with the elution fractions of A subunit by producing anti-A-subunit and anti-B-subunit serum antibody responses, whereas mice immunized with elution fractions of B subunit produced only antibodies specific for the B subunit. An equimolar amount of the two resulting protein peaks was used to immunize two groups of rabbits. Rabbits immunized with A subunit, produced a serum anti-B subunit response equal to that of rabbits immunized with the B subunit. Rabbits immunized with equimolar concentrations of A and B subunits were observed to be equally protected against intestinal loop challenge with Vibrio cholerae Inaba V86. The A subunit, not the B subunit, was biologically active when tested by the S49 mouse lymphosarcoma cell test. These studies provide additional evidence supporting the hypothesis that the A subunit, specifically of alpha chain, of cholera toxin contains antigenic determinants in common with the B subunit.

Animals

Increased prevalence of mature females bearing pigmented oocytes from populations of Minnesota Rana pipiens.

Mature female leopard frogs, Rana pipiens, collected from several sites in Minnesota from 1967 through 1977, were examined for the presence of pigmented oocytes. An increase in the percent of mature females with pigmented oocytes was observed in the frogs captured in 1977 compared to those captured earlier. Coincident with the increase in prevalence of females with pigmented oocytes, there was a decline in abundance of the frogs.

Animals

Galactocerebrosidase activity in canine globoid leukodystrophy.

In an investigation of canine globoid leukodystrophy, cerebroside beta-galactosidase activities were assayed in 24 brains from neonatal and older dogs and in 90 canine leukocyte pellets from nine samplings. The neonatal brains had significantly less enzyme activity than the brains of older dogs, which indicates a potential complication in making neonatal and fetal enzymatic diagnoses. For leukocytes, heterozygous activities averaged 51 percent and globoid leukodystrophy activities 18 percent of mean enzyme activity of normal leukocytes. Variability of leukocyte enzyme activities among the nine samplings was large, but within each sample, variability per genotypic category was moderate. A statistical model was developed to facilitate enzyme diagnosis in the dog and, by implication, in human globoid leukodystrophy and other sphingolipidoses.

Animals