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Biomedical subjects

L Evans

Publications and source records attributed to L Evans.

At least 145 records · Page 8Linked to original sources
PubMed1986

Double pair comparison--a new method to determine how occupant characteristics affect fatality risk in traffic crashes.

A new method to determine how occupant characteristics affect fatality risk in traffic crashes is developed. The method, which uses data from the Fatal Accident Reporting System (FARS), focuses on two occupants, a "subject" occupant and an "other" occupant. The probabilities of a fatality to the subject occupant when that occupant has one of two characteristics are compared. The other occupant serves essentially a normalizing, or exposure estimating, role. The method uses only fatality frequency data--no external exposure information is required, and it is relatively free from uncertain assumptions. It has wide applicability; examples of potential applications include investigating car occupant fatality risk as a function of sex, age, alcohol use or motorcyclist fatality risk as a function of helmet use. The first application is to determining the effectiveness of safety belts in preventing car occupant fatalities, as described in the paper following this paper.

Accidents, Traffic↗
PubMed1986

The effectiveness of safety belts in preventing fatalities.

The effectiveness of safety belts in preventing fatalities to drivers and right front passengers is estimated by applying the double pair comparison method to 1974 or later model year cars coded in the Fatal Accident Reporting System. The method focuses on "subject" occupants (drivers or right front passengers) and "other" occupants (any except the subject occupant). Fatality risks to belted and unbelted subject occupants are compared using the other occupant to estimate exposure. In this study, drivers and right front passengers are subject occupants; choosing other occupants differing in age, seating positions, and belt use, generated 46 essentially independent estimates of safety belt effectiveness. The weighted average and standard error of these is (41 +/- 4)%. This finding agrees with the 40%-50% range reported in a recent major review and synthesis by the National Highway Traffic Safety Administration. Combining this with the present determination gives (43 +/- 3)%; that is, if all presently unbelted drivers and right front passengers were to use the provided three point lap/shoulder belt, but not otherwise change their behavior, fatalities to this group would decline by (43 +/- 3)%.

Accidents, Traffic↗
PubMed1986

Risk homeostasis theory and traffic accident data.

The risk homeostasis theory posits, in essence, that a control mechanism analogous to the thermal homeostatic system in warm-blooded animals tends to keep risk per unit time constant, and, as a consequence, the number of traffic accidents per unit time of driving also tends to remain constant, essentially independent of changes in the traffic safety system. It is the purpose of the present research to examine the validity of this claim using a wide variety of traffic accident data. All the data examined are found to be incompatible with the risk homeostasis theory. The only specific field accident data offered in the literature to support the risk homeostasis theory are found to, in fact, refute the theory. The accident data provide evidence that a rich variety of user responses occur. While it is possible for users to collectively respond in such a way that safety benefits are completely cancelled, such a response is not particularly common; it is certainly not universally occurring, as suggested by the risk homeostasis theory. It is concluded that the risk homeostasis theory should be rejected because there is no convincing evidence supporting it and much evidence refuting it.

Accidents, Traffic↗
PubMed1986

Effect of a selective serotonin uptake inhibitor in agoraphobia with panic attacks. A double-blind comparison of zimeldine, imipramine and placebo.

A double-blind clinical trial of zimeldine, a potent inhibitor of central serotonin reuptake, versus imipramine and placebo was carried out on 44 patients suffering from agoraphobia with panic attacks. Zimeldine was a superior treatment on all rating scales other than a global rating scale which did not reach statistically significant superiority. Imipramine was not shown to be superior to placebo. The implications of these results for further research on the underlying pathophysiology of agoraphobia with panic attacks are discussed.

Adult↗
PubMed1986

Analysis of two strains of Friend murine leukemia viruses differing in ability to induce early splenomegaly: lack of relationship with generation of recombinant mink cell focus-forming viruses.

Friend murine leukemia helper viruses (F-MuLV) 57 and B3 were indistinguishable by genomic structural analyses with RNase T1-resistant oligonucleotide fingerprinting and by antigenic reactivity with a panel of 31 monoclonal antibodies directed against murine leukemia viruses. Nevertheless, F-MuLV 57 and B3 had strikingly different virulences. Approximately 2 months after inoculation, IRW and NFS/N mice inoculated as newborns with F-MuLV 57 had gross splenomegaly caused by erythroid proliferation. In contrast, an equivalent dose of F-MuLV B3 induced spleen or lymph node enlargement 4 to 13 months after inoculation. Although most cases of spleen enlargement in F-MuLV B3-inoculated mice were due to erythroid proliferation, lymphoid or myeloid proliferation was also frequently observed. The replication of both F-MuLV 57 and B3 was equally efficient, and both viruses generated recombinant dual-tropic mink cell focus-forming (MCF) viruses with the same kinetics and efficiency. Moreover, MCF viruses induced by F-MuLV 57 and B3 had the same antigenic patterns. Therefore, the ability of F-MuLV to induce early splenomegaly did not correlate with the generation of recombinant MCF viruses.

Animals↗
PubMed1986

Comparisons among heterosexual, bisexual, and homosexual male sadomasochists.

Between 1982 and 1984 a questionnaire designed to elicit demographic and behavioral information concerning individuals who participate in sadomasochism (S&M) was distributed nationally. Data from 136 heterosexual, 45 bisexual, and 91 homosexual male sadomasochists (N = 272) were analyzed. Similarities and differences among these three groups in response to 15 of the 40 questions asked concerning age and manner of first S&M interest, openness with others concerning those interests, self image and adjustment, sexual behavior, and sex role orientation are reported and compared to findings previously reported by Spengler (1977), Lee (1979), Kamel (1980), Weinberg & Falk (1980) and Weinberg, Williams, & Moser (1984). Issues concerning the categorization of the respondents into appropriate S&M sex role types are also discussed.

Gender Identity↗
PubMed1985

On the prevalence and roles of females in the sadomasochistic subculture: report of an empirical study.

The existence of females in the sadomasochistic subculture has generally been denied in the theoretical, clinical, and empirical literature. The assumption that females do not exist in the subculture, or exist in such small numbers as to make analysis impossible, was tested. Questionnaires were placed in two publications that cater to sadomasochists, and additional questionnaires were mailed to advertisers whose ads appeared in a sadomasochistic contact magazine. Of 182 individuals who responded, 130 were males, and 52 were females, indicating a meaningful female presence in the subculture. An analysis of the replies revealed similarities and differences between the male and female respondents.

Adult↗
PubMed1985

Involvement rate in two-car crashes versus driver age and car mass of each involved car.

This work was performed to investigate how the likelihood of a two-car crash depends on the driver age and car mass for each of the two involved cars, and also to examine the special case of cars of similar mass crashing into each other. Data on 108 044 cars involved in police reported two-car crashes occurring in New York State in 1971 and 1972 were fitted to a function of the driver age and car mass for each of the two involved cars. Car registrations are used to estimate exposure. The special case of crashes between cars of similar mass is considered because of prior results on driver injuries in such crashes. It is found that "small-small" crashes (defined as a 900 kg car crashing into another 900 kg car) are about 0.3 times as likely as "big-big" crashes (an 1800 kg car crashing into another 1800 kg car), assuming equal numbers of cars driven by drivers of the same age. Combining the present results with earlier findings of increased injury risk in small-small crashes gives that such crashes injure about 70% as many drivers as big-big crashes when normalized for numbers of cars and driver age. That is, it is concluded that small-small crashes produce 30% fewer injuries than do big-big crashes.

Accidents, Traffic↗
PubMed1985

Driver age, car mass and accident exposure--a synthesis of available data.

The tendency of younger drivers to be more likely than older drivers to drive smaller cars has been an important consideration in a number of prior investigations of the relation between car size and traffic safety. The purpose of the present study is to quantify this effect on a firmer basis than hitherto by fitting data from seven independent sources to a unified general model. More specifically, when the exposure measures "per unit distance of travel" or "per registered car" are used in studies of car mass effects on traffic safety, the exposure information often does not contain the variable driver age. This work develops a general procedure for disaggregating such exposure data into three driver (or owner) age categories; A1: 16-24; A2: 25-34; and A3: greater than or equal to 35 years. Data from the seven sources are fitted to the equation f(i,m) = Hi[1 + Gi(m/900-1)] where m is the car mass in kg, and f(i,m) is the fraction of cars of mass m which are driven (owned) by persons in the Ai (i = 1, 2, 3) age category. The form of this equation permits easy comparison of 900 and 1800 kg cars. Those particular masses that have been chosen for illustrative comparisons in earlier work. The seven sets of data are used to derive overall average values of the parameters Hi and Gi. The data from all seven sources show consistent effects which are summarized in one analytical expression which is well suited for use in future studies of car size effects because it reflects a synthesis of much prior data and it permits sensitivity analyses to be performed conveniently.

Accidents, Traffic↗
PubMed1985

Fatality risk for belted drivers versus car mass.

This study was performed to determine how the likelihood of a belted driver being killed in a single car crash depends on the mass of the car. This was done by applying the pedestrian fatality exposure approach to the subset of fatalities in the Fatal Accident Reporting System (FARS) for which the driver was coded as using a shoulder belt and/or a lap belt. Combining the 1975 through 1982 data provided a sufficiently large population of belted drivers to perform the analysis. In the exposure approach used, the number of car drivers killed in single car crashes is divided by the number of nonoccupant fatalities (pedestrians or motorcyclists) associated with the same group of cars. The ratio is interpreted to reflect the physical effect of car mass, essentially independent of driver behavior effects. In the present application, car mass effects for belted drivers were determined by considering the number of belted drivers killed divided by the number of nonoccupants killed in crashes involving cars whose drivers were coded in the FARS files as being belted. Because the belt use of surviving drivers is, to some extent, self-reported, it is considered that the data given in the report should be not used to estimate the effectiveness of seat belts in preventing fatalities. The results are presented as graphical and analytical comparisons of fatality likelihood versus car mass for belted and unbelted drivers. It is concluded that the effect of car mass on relative driver fatality likelihood is essentially the same for belted and unbelted drivers (for example, the present analysis gives that a belted driver in a 900 kg car is 2.3 times as likely to be killed in a single car crash as is the belted driver in an 1800 kg car. The corresponding ratio determined here for unbelted drivers is 2.4). As a consequence of this conclusion, the relative effectiveness of seat belts in preventing driver fatalities is similar for cars of different masses.

Accidents, Traffic↗
PubMed1985

Expression of the herpes simplex virus type-2 major DNA-binding protein (ICP8) gene in COS-1 cells.

By the use of an SV40 origin of replication plasmid vector and the COS-1 cell system, expression of the gene encoding the herpes simplex virus type-2 (HSV-2) major DNA binding protein (ICP8) has been achieved. The HSV-2 4.5 kb BglII 0 DNA fragment containing the ICP8 coding region was inserted into the plasmid vector pSVOd containing the SV40 origin of replication. Transfection of COS-1 cells by the resultant recombinant plasmid (pSVOd20), and subsequent multiplication of this plasmid, led to the production of the HSV-2 major DNA binding protein in sufficient quantities to allow its detection with either monoclonal or polyclonal antibodies as well as sera taken from HSV-2 patients.

Animals↗
PubMed1985

Influence of the centrosome on the structure of nucleated microtubules.

The capacity of the centrosome to influence the lattice structure of nucleated microtubules was studied in vitro. Brain microtubules self-assembled to give predominantly (98%) 14-protofilament microtubules. However, under exactly the same conditions of assembly they grew off of purified centrosomes from neuroblastoma cells to give mostly (82%) 13-protofilament microtubules. Thus, the nucleation sites on the centrosome constrained the microtubule lattice to yield the number of protofilaments usually found in vivo.

Animals↗
PubMed1985

Proximity to retirement and anticipatory involvement: findings from the Normative Aging Study.

This study investigated the level of workers' informal retirement-oriented behavior in the years preceding retirement. Two research questions were addressed: (a) What is the relationship between retirement proximity and preretirement involvement behaviors, and (b) How might retirement involvement levels be further affected by attitude toward retirement, job characteristics, and personal resources? Data were collected from 816 male workers participating in a long-term panel study of aging who anticipated retiring within the next 15 years. Results indicated that preretirement involvement increased with retirement proximity and that the association held even among men who dreaded retirement or were satisfied with their jobs. These findings suggest that a process of anticipating retirement is underway well in advance of withdrawal from work and that a gathering involvement in retirement is normative as the event approaches.

Aged↗
PubMed1985

Congenital selective malabsorption of glucose and galactose.

We review here the case histories and results of in vivo and in vitro tests for eight children with congenital selective glucose and galactose malabsorption (GGM) whom our laboratory has followed up since 1971. Clinically, GGM was manifested by intractable, acidic, sugar-containing diarrhea that started during the neonatal period. Diarrhea only abated when glucose and galactose were removed from the diet. The disease was notable for the absence of other symptoms, although mellituria was a common finding. Defective sugar transport was permanent, but sugar tolerance appeared to increase with age. In vitro, intracellular mucosal glucose concentration (C) was significantly below control level in GGM intestinal tissue for concentrations (M) of 10 and 0.1 mM glucose in the medium. C/M for galactose also decreased, while the C/M ratios for alanine and xylose were within the control range. Glucose influxes across the luminal membrane, net glucose transepithelial fluxes, and electrical parameters were all consistent with defective sodium and glucose cotransport at the brush border membrane of jejunal epithelial cells. However, the present results are also consistent with a small residual active transport system observed only at low glucose concentration in the medium. Further observations are needed to establish the role of glucose transport systems in absorption of other monosaccharides, the relationship between kidney and intestinal sodium-glucose cotransport systems, and their genetic control.

Biological Transport, Active↗