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This paper presents the preliminary results of a project aimed at developing models that can be used by planners and highway engineers for predicting pollutant runoff from highways. A brief review of different approaches to predicting pollutant runoff loads from highways is followed by a description of the data base being assembled as a part of this project. The probabilistic data analysis methodology that is being used to characterize highway stormwater runoff is then described in some detail. Preliminary analytical results are presented in two main areas-rainfall and runoff data and water quality data. For the sites examined so far, it is shown that taking the percent imperviousness of an unmonitored site as its runoff coefficient, with an upper bound of around 0.9 to account for initial abstraction, offers a reasonable first estimate. Best estimates for pollutant concentrations for each of six pollutants are presented and compared with corresponding values for urban runoff. Lacking site specific data, they represent reasonable first estimates of highway stormwater runoff quality.

During the aggregation of Dictyostelium discoideum extracellular cAMP is known to act as a chemotractant and as an inducer of cellular differentiation. However, its intracellular role as a second messenger remains obscure. We have constructed a fusion gene consisting of the cDNA encoding the regulatory subunit (R) of the cAMP-dependent protein kinase fused to the promoter and N-terminal-proximal sequences of a Dictyostelium actin gene. Stable transformants, containing multiple copies of this gene, overproduce the R subunit which accumulates prematurely relative to the endogenous protein. These transformants fail to aggregate. Detailed analysis has shown that they are blocked at interphase, the period prior to aggregation, and that they are severely defective in most responses to cAMP including the induction of gene expression. Our observations suggest that intracellular cAMP acts, presumably by activation of the catalytic subunit of the cAMP-dependent protein kinase, to facilitate early development.

The effect of amobarbital sodium (ABS) on contrast effects in consummatory behavior was investigated in three experiments. In Experiment 1, rats were shifted from 32% sucrose to 4% sucrose after 11 days’ experience with the 32% solution. ABS (15, 17.5, and 20 mg/kg) was administered during the final three preshift days and throughout the postshift period. Contrast was not reduced by this treatment, and, in fact, the higher doses tended to retard recovery from contrast. In Experiment 2, ABS (17.5 mg/kg) was injected on the 1st and 2nd postshift days only. Under these administration conditions, the drug reduced degree of contrast. In Experiment 3, ABS (12, 17.5, 22 mg/kg) tended to enhance the degree of simultaneous negative contrast that occurred when rats were repeatedly shifted between 32% and 4% sucrose. Thus, the conditions under which ABS might be expected to reduce contrast in consummatory behavior are restricted. Similarities and differences in the effects of ABS, chlordiazepoxide, and ethanol on contrast are discussed.

The present study examined the effects of physostigmine, a cholinesterase inhibitor, on activity in young rats whose mothers consumed isocaloric liquid diets containing 35% or 0% ethanol-derived calories on days 6-20 of pregnancy. A pair-feeding procedure was utilized and an ad libitum lab chow group was included. Physostigmine was administered to 18-day-old offspring on 3 consecutive days with activity measures recorded for 30 min each day. Injections of physostigmine produced significant reductions in activity in alcohol-exposed offspring relative to control groups. These results provide support for a functional cholinergic deficit in offspring exposed to alcohol in utero and may have relevant clinical implications in the treatment of attentional deficit disorder which can occur following prenatal alcohol exposure.

The effect of prenatal alcohol exposure on nipple attachment behavior was studied at a number of ages in rat pups whose mothers consumed liquid diets containing 35% or 0% ethanol-derived calories (EDC) or standard lab chow during pregnancy. In the first experiment, nondeprived pups were tested in groups of three (one from each of the prenatal treatment groups) for nipple attachment to an anesthetized lab chow dam. The second experiment examined the influence of the type of test dam (35% EDC, 0% EDC, or lab chow) on nipple attachment behavior. Finally, experiment three evaluated the possibility that the data from the preceeding experiments were the result of either testing the offspring in triads or alcohol-induced alterations in maternal behavior. Rat pups from all three groups reared by their biological mothers and a group of 35% EDC offspring fostered at birth to lab chow surrogate mothers were tested alone rather than in triads. The data from all three experiments clearly indicated an age-related pattern of nipple attachment behavior; the latency to attach was shortest in 6- to 12-day-old pups and increased rapidly from 13 to 21 days of age. Prenatal exposure to alcohol significantly increased the latency to attach to the nipple and the rank order of attachment at the younger ages (three to nine days of age) but not in the older animals. Also, the prenatal effect of alcohol was independent of the type of dam to which testing was conducted, the social interaction involved in testing triads, or fostering procedures. These results suggest that prenatal alcohol exposure can interfere with the development of normal suckling behavior, which might influence normal growth.

To assess the significance of pollutant loads from highways, in terms of the extent to which they may cause adverse impacts on a beneficial use, the cumulative frequency distribution of pollutant concentrations downstream of the highway discharge is computed and may be compared with concentration levels at which a particular adverse effect will be produced. The model described can be used to compute the frequency or recurrence of storm runoff events that result in violations of water quality criteria or other effects levels. Data collected at highway sites throughout the US are used to evaluate the statistical properties of highway runoff flows and concentrations; regional values for precipitation and streamflow from standard monitoring programs are used to provide the other necessary input parameters.

A field trial of artificial insemination in horses with transproted, chilled semen was conducted using a specially designed container which permitted a controlled, slow initial rate of cooling (-0.3 degrees C/min) and maintenance of a final temperature of 4 degrees -6 degrees C for more than 36 hrs. Forty-six mares in 23 states were inseminated with semen from three German Warmblood stallions standing at stud in Hamilton, Massachusetts. A third-cycle conception rate of 91% was obtained.

Septic arthritis of the shoulder is uncommon in adults. We reviewed the cases of eighteen patients who were followed for a minimum of one year. The patients ranged in age from forty-two to eighty-nine years. All but one patient had at least one serious associated disease. Eight patients had had an injection or aspiration of the shoulder before development of the infection. All but one patient had had a delay in diagnosis. At the time of admission to the hospital, the erythrocyte sedimentation rate was always elevated, but the body temperature and white blood-cell count were not. After treatment, the functional result was usually poor: only five patients regained forward flexion to 90 degrees or more, eight patients had no active motion of the glenohumeral joint, and two patients died. Arthrotomy appeared to afford a better result than did repeated aspiration.

Two large-scale in situ shear tests were conducted at a damsite in western Canada. The rock at the site is a Cretaceous shale containing a thin clay seam tentatively identified as a bedding-plane shear zone. The material in this seam is significantly weaker than the intact rock and influences the design of certain features of the dam and structures. In order to provide shear strength data for design, two large blocks of shale were sheared along the clay seam. These tests differed from conventional in situ shear tests in two significant ways: the rate of shear displacement was strictly controlled, and pore pressures (both positive and negative) in the shear zone were carefully monitored throughout the test. This note presents the material properties of the shear zone, describes the test equipment and techniques, and discusses the results obtained. Key words: shear strength, in situ testing, pore pressure, shale.

Two aspects of efforts to disseminate an innovative computer-assisted instructional system called PLATO between 1972 and 1976 are addressed. The first pertains to the dissemination problems encountered and resolved by the system developers. The second covers dissemination modus operandi chosen by the developers to bring PLATO to the attention of large numbers of people. An ex post facto analysis of data obtained suggested PLATO developers made dissemination decisions that reflected viable dissemination theory and practice of the time, committed substantial resources to the dissemination process, and selected what appeared to be a cost-effective marketing strategy. Perhaps the most important consequence of these actions is that PLATO flourished throughout the 1970s and continues to flourish.

Parallels between the behavioral profiles of rats exposed to alcohol prenatally and those with hippocampal damage suggest that hippocampal dysfunction may underlie some of the behavioral abnormalities resulting from prenatal alcohol exposure. Because of possible hippocampal involvement in the acquisition of a delayed conditioned taste aversion, this task was assessed in rat pups exposed to alcohol prenatally. Long-Evans rats were maintained on liquid diets containing either 35% or 0% ethanol derived calories from Days 6–20 of gestation. Pair-feeding procedures and an ad lib Lab Chow (LC) group were included. Fifteen-day-old offspring from these three groups were given access to saccharin and then injected immediately (0 hr) or 2 hr later with either lithium chloride (LiCl) or sodium chloride (NaCl). Immediate pairing of saccharin with LiCl produced a marked taste aversion, although this effect was less pronounced in 35% EDC pups. In the 2 hr condition, weaker aversions were exhibited and again the 35% EDC group showed the least aversion. However, prenatal treatment did not interact with the injection interval.

The present experiments investigated the role of signals for pellet delivery in the development of polydipsia on random time schedules. In Experiment 1, when an explicit signal or auditory stimulation from pellet dispenser operation was available to the rats, polydipsia developed in all ofthe animals. In Experiment 2, animals receiving signaled pellet deliveries developed poly­ dipsia more quickly than those receiving unsignaled pellet deliveries. Furthermore, behavioral observations suggested that animals showing polydipsia in the unsignaled group may have been able to detect the operation of the pellet dispenser despite our attempt to mask such cues. In Experiment 3, the information value of pellet-dispenser cues was degraded by the operation of an empty pellet dispenser during the interpellet interval. Under these conditions, almost all animals did not develop polydipsia and the data suggest that for the few that did, pellet-dispenser cues were probably not responsible. Thus, the present findings suggest two conclusions: (1) In studies reporting polydipsia on random schedules, the animals may have been inadvertently provid­ ed with cues for pellet availability, and (2) although Pavlovian conditioning may be an impor­ tant modulator of adjunctive behavior, other factors must also be considered.

The present study examined the influence of a signal for pellet delivery on the development and maintenance of polydipsia on fixed and variable time schedules. It was found that animals receiving a signal for pellet delivery developed polydipsia more quickly and had higher intake levels than animals not receiving such a signal on both schedules. These data support predictions derivable from the application of Pavlovian conditioning principles to the schedule-induced polydipsia phenomena.

Verapamil has been studied extensively in adult animals. However, there is limited data about the effects of this antiarrhythmic agent in young animals. We studied the electrophysiologic and hemodynamic effects of verapamil in 5 awake, chronically instrumented puppies and in 6 anesthetized, acutely instrumented puppies. We compared the responses in puppies to those in 7 awake, chronically instrumented adult dogs and in 6 anesthetized, acutely instrumented adult dogs. In the awake, chronically instrumented animals, we measured heart rate and the effective refractory period of the atrio-ventricular specialized conduction system (ERP-AVSCS). In the anesthetized, acutely instrumented preparation, we measured heart rate, ERP-AVSCS, mean right atrial and systemic arterial blood pressure, and velocity of blood flow in the aorta, carotid and femoral arteries. We infused verapamil intravenously at doses of 50, 100, 200 and 400 microgram/kg. Verapamil (400 micrograms/kg) increased the ERP-AVSCS by 64% in awake, chronically instrumented puppies; 62% in awake, chronically instrumented adult dogs; 125% in anesthetized, acutely instrumented puppies, and 120% in anesthetized, acutely instrumented adult dogs. The effect of verapamil upon heart rate and ERP-AVSCS was more pronounced in anesthetized animals than in awake animals. Mean systemic arterial blood pressure was reduced by verapamil in anesthetized, acutely instrumented puppies and adult dogs. Verapamil reduced the velocity of aortic, femoral and carotid artery blood flow in anesthetized, acutely instrumented puppies.

Amobarbital sodium (17.5 mg/kg) produced equivalent reductions in negative contrast when injected for the first time on either day 1 or 2 following a shift from 32% to 4% sucrose. These results differed from those obtained in earlier studies with chlordiazepoxide.

Publisher Summary This chapter presents a series of experiments for identification of a set of neck injury criteria suitable for representing serious neck injuries sustained by car crash occupants. Cervical spinal injuries have been studied and some injury threshold data for static and dynamic neck loads already exists. The first test of an initial static neck loading test series has been conducted in this program; specifically, a neck tension test of an anesthetized, 12.2 kg, eight-year-old female baboon (Papio hamadryas) is reported. A static tensile loading experiment performed on an anesthetized Papio hamadryas produced neurophysiological evidence that cervical spinal cord function had been seriously impaired at 51% of the load subsequently required for the occurrence of structural failure. It appears likely that dynamic neck loading experiments will confirm that serious functional impairment of the neck can be produced at load levels well below those that cause structural failure of the neck. Existing anthropomorphic automotive test dummies have generally been developed based upon biomechanical data generated from testing performed on human cadavers.

Septic arthritis of the shoulder is uncommon in adults. We reviewed the cases of eighteen patients who were followed for a minimum of one year. The patients ranged in age from forty-two to eighty-nine years. All but one patient had at least one serious associated disease. Eight patients had had an injection or aspiration of the shoulder before development of the infection. All but one patient had had a delay in diagnosis. At the time of admission to the hospital, the erythrocyte sedimentation rate was always elevated, but the body temperature and white blood-cell count were not. After treatment, the functional result was usually poor: only five patients regained forward flexion to 90 degrees or more, eight patients had no active motion of the glenohumeral joint, and two patients died. Arthrotomy appeared to afford a better result than did repeated aspiration.

The long-term clinical course was studied in 646 patients, who underwent isolated operative repair of coarctation of the aorta at the Mayo Clinic from 1946 to 1981. There were 17 perioperative deaths, and 58 patients were lost to follow-up. Of the 571 patients with long-term follow-up, 11% required subsequent cardiovascular surgery, and 25% developed hypertension. There were 87 late deaths. The mean age at death was 38 years (range, 0-67 years). Estimated survival analysis revealed 91% of patients alive at 10, 84% at 20, and 72% at 30 years after operative repair. The most common cause of late death was coronary artery disease in 32 patients, followed by sudden death, heart failure, cerebrovascular accidents, and ruptured aortic aneurysm. Age, sex, and postoperative systolic blood pressure were found to be independently predictive of survival. For patients less than 14 years of age at the time of initial coarctectomy, survival to 20 years was 91%, and for patients 14 years or older at the time of operation, survival was 79%. The best survivorship was observed in patients operated on at 9 years of age or less. The higher the postoperative systolic pressure, the higher the probability of death. This study has the largest population undergoing repair of coarctation of the aorta with a median follow-up of as long as 20 years. Four main points emerged. 1) Age at the time of initial repair is the most important predictor of long-term survival. Surgery should be offered to patients after age 1 year or sooner if hypertension is severe. 2) Coronary artery disease is the most common cause of late death.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-Evans, hooded rats were intubated with one of four dose combinations of pentazocine and tripelennamine on Days 7-20 of pregnancy: 0:0 (mg/kg pentazocine:tripelennamine), 20:10, 40:0, or 40:20. An additional group had free access to lab chow and water throughout pregnancy. At birth, reduced body weights were evident in all drug-treated offspring. Growth deficits were not noted at 5, 10, 15 or 20 days of age. Three measures of activity were collected at 18 days of age, however, none of these measures were differentially affected as a function of prenatal treatment. At 85 days of age, offspring were tested in a two-way shuttle avoidance paradigm. Although the number of avoidances was not significantly affected by prenatal treatment, offspring exposed to these drugs in combination had shorter response latencies than controls with increased training and made more intertrial crossing responses. Additional offspring were tested for seizure susceptibility at 100 days of age. None of the parameters of seizure activity were significantly affected by prenatal drug treatment. Prenatal exposure to pentazocine and tripelennamine resulted in prenatal growth deficits, increased activity during the intertrial interval and decreased response latencies in a shuttle avoidance learning task, suggesting that this polydrug combination may be associated with some long-term behavioral teratogenic risks.

The patterns of inpatient use of Madang Hospital were examined. A highly disproportionate use of the hospital by the neighbouring population was demonstrated. The implications of this for health care planning are discussed and some methods of alleviating the inequalities in health care provision to urban as opposed to rural communities are suggested.

Brain sectioning has been improved through gelatin embedding so that more than forty precisely oriented serial sections can be obtained from a single brain. Since the embedding gelatin requires no fixation, it can be removed from the sections prior to staining by simple warming. The reduction of Berlin blue dye commonly observed after staining by the Mulligan method has been found to be at least partly due to light in the UV to near UV range. Dye reduction is significantly inhibited by postfixation in 25% acetic acid.

We report on a three‐terminal tunneling experiment on a semiconductor quantum dot in the Coulomb blockade regime. The set‐up allows us to measure directly the conductance matrix of this closed system. In the weak coupling regime, we can determine the coupling strengths of the dot to its individual leads. The independant fluctuations of these coupling strengths as a function of the electronic state are attributed to fluctuations of the shape of the wave function in the dot.

We have performed transport measurements on a composite nanostructure, consisting of a quantum dot and a nearby quantum point contact (QPC) used as a charge detector. For very low coupling of the dot to only one of the reservoirs and no coupling to the other one, we observe time‐dependent features related to electron tunneling onto the dot and back to the reservoir. The transition frequencies visible in the QPC signal are of the order of only a few Hz. From these time‐dependent data, the Fermi distribution in the lead and the temperature can be extracted, as well as the coupling to the reservoir.

The shortage of resources for providing renal replacement makes it essential to reduce revenue costs wherever possible. Assuming that haemodialysis is likely to remain a mainstay of renal replacement, a policy of reusing the expensive disposable dialysers and blood lines could offer substantial cost savings. Such reuse has been shown to be safe and to maintain efficiency, but it must also take account of convenience to the patient, especially those dialysing at home. A survey of patients treated with home dialysis shows that the rate of reuse of the complete extracorporeal circuit was highest for those patients who had automated reuse systems.