Showing papers by "United States Department of the Army published in 1985"

Rift Valley fever virus (family Bunyaviridae, genus Phlebovirus). Isolations from Diptera collected during an inter-epizootic period in Kenya

Abstract: A total of 134 876 Diptera collected in Kenya during a 3-year period were tested in 3383 pools for Rift Valley fever (RVF) virus. Nineteen pools of unengorged mosquitoes were found positive for RVF. All isolations were made from specimens collected at or near the naturally or artificially flooded grassland depressions that serve as the developmental sites for the immature stages of many mosquito species. The isolation of virus from adult male and female A. lineatopennis which had been reared from field-collected larvae and pupae suggests that transovarial transmission of the virus occurs in this species.

Frequency of illness associated with epidemic hepatitis a virus infections in adults

Abstract: Hepatitis A virus infection is often described as mild or asymptomatic, particularly in children. The failure of most adults who are found to be immune to remember symptoms of an illness suggestive of hepatitis A virus supports this belief. In 1982, two large outbreaks occurred in well documented populations of military personnel. These outbreaks were each extensively studied epidemiologically and serologically. It was found that 28/29 (96.6%) hepatitis A infections recognized prior to immune serum globulin in Outbreak A and 35/46 (76.1%) infections in Outbreak A were symptomatic. Symptomatic cases failed to occur beyond eight days of immune serum globulin administration to these predominantly susceptible groups. Between 40 and 70% of patients were icteric. Apparent contrasts in symptoms associated with hepatitis A infection in adults and children suggest a basic age-dependent difference in immune response to such infection.

Adhesives Technology Handbook

Abstract: Comprehensive technical treatment of the field of structural adhesive bonding. The data categories include: Definition of Terms; Joint Design and Design Criteria; Surface Preparation of Adherends; Adhesive Types and Their Properties and Applications; Adhesives for Specific Adherends; The Adhesive Bonding Process; Solvent Cementing of Plastics; Effects of Environment on Durability of Adhesive Joints; Quality Control; Test Methods; Standard Specifications and Test Methods (235); Applications of Adhesive Bonding; Appendix -- Sources of Information. -- AATA

The Walter Reed performance assessment battery.

Abstract: This paper describes technical details of a computerized psychological test battery designed for examining the effects of various state-variables on a representative sample of normal psychomotor, perceptual and cognitive tasks. The duration, number and type of tasks can be customized to different experimental needs, and then administered and analyzed automatically, at intervals as short as one hour. The battery can be run on either the Apple-II family of computers or on machines compatible with the IBM-PC.

Applications of cellulases.

Abstract: Acto 523, 133-146 Shoemaker, S. P. & Brown, R. D., Jr. (1978b) Biochim. Biophys. Acra 523. 147-161 Shoemaker, S., Schweickart, V., Ladner, M., Gelfand, D., Kwok, S., Myambo, K. & Innis, M. (1983) Biofechnology October issue, 69 1 6 9 6 Sternberg, D. & Mandels, G . R. (1979) J . Bacteriol. 139, 761769 Stewart, B. J . & Leatherwood, J . M. (1976) J. Bacteriol. 129,609615 Teeri, T., Salovuori, 1. & Knowles, J . (1983) Biofechnology October issue, 696699 Vaheri, M. P., Vaheri, M. E. 0. & Kauppinen, V. S. (1979) Eur. J. Appl. Microbiol. Biotechnol. 8, 73-80 Weber, M., Foglietti, M. J. & Percheron, F. (1980) J. Chromatogr.

Twenty-five year review of Pseudomonas aeruginosa bacteremia in a burn center

Abstract: The incidence ofPseudomonas aeruginosa bacteremia was examined in 5,882 burn patients consecutively admitted over a 25-year period to one burn center. The population examined had an average burn size of 33.8 % of the body surface and an average age of 26.3 years.Pseudomonas aeruginosa bacteremia occurred in 540 patients. These patients had an average burn size of 54.2 % and average age of 28 years. Mortality was 77 %. Bacteremia with other organisms occurred during hospitalization of all but 128 of the 540 patients. Comparison of predicted mortality based on burn size and age to observed mortality showedPseudomonas aeruginosa bacteremia to be associated with a 28 % increase in mortality. Examination of mortality as a function of time showed no significant change over the 25-year period. The incidence ofPseudomonas aeruginosa colonization and infection was examined in 400 recently admitted burn patients. Colonization occurred in 107 and 34 infections were recorded in 27 of the colonized patients.

Hole Removal in Thin-Gate MOSFETs by Tunneling

Abstract: Fast time-resolved measurements of the response of thin-oxide MOSFETs show that radiation-induced holes are removed from the gate oxide by a tunneling process. A tunneling rate of 0.35 nm/decade from each interface is found for SiO2 at 77 K. Fast time-resolved measurements performed at room temperature are in qualitative agreement with low-temperature annealing data. Uncertainties in the room-temperature data did not allow extraction of firm and reliable values for the tunneling parameters.

Role of Consumer Expectancies in the Acceptance of Novel Foods

Abstract: Six experiments were conducted to examine factors affecting the consumer acceptance of novel foods. Variables included for analyses of their effects were: (1) preparation variables; (2) product name and type of serving vessel; (3) brand labels and packaging; (4) availability of product information; (5) nature and quantity of product information; and (6) degree of familiarity of the user with the product. Results of these experiments were interpreted within a theoretical framework that postulates that the hedonic response to food is a function of the degree to which expectancies about the food are matched by subsequent experiences with it. Based on the theory of cognitive dissonance, this theoretical framework is proposed as a useful analytic tool for predicting consumer responses to novel foods.

Influence of Heat Stress and Acclimation on Maximal Aerobic Power

Abstract: Thirteen male volunteers performed cycle ergometer maximal oxygen uptake ( $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ tests) in moderate (21‡ C, 30% rh) and hot (49‡ C, 20% rh) environments, before and after a 9-day heat acclimation program. This program resulted in significantly decreased (P<0.01) final heart rate (24 bt·min−1) and rectal temperature (0.4‡ C) from the first to last day of acclimation. The $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ was lower (P 0.05) shown for maximal power output (PO max, watts) between environments either before or after acclimation. The $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ was higher (P<0.01) by 4% after acclimation in both environments. Also, PO max was higher (P<0.05) after acclimation in both the moderate (4%) and hot (2%) environments. The reduction in $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ in the hot compared to moderate environment was not related to the difference in core temperature at $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ between moderate and hot trials, nor was it strongly related with aerobic fitness level. These findings indicate that heat stress, per se, reduced the $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ . Further, the reduction in $$\dot V_{{\text{O}}_{{\text{2max}}} }$$ due to heat was not affect be state of heat acclimation, the degree of elevation in core temperature, or level of aerobic fitness.

Sex Differences in Risk Taking: Repeated Sessions on a Computer-Simulated Task

Abstract: Two experiments were conducted to investigate sex differences in risktaking behavior on a computer-generated and controlled task. Male and female subjects faced a video display of simulated mine fields with varying numbers and patterns of dots representing mines in the fields. In Experiment 1, they estimated the probability that a tank might successfully cross 100 mine fields when starting from an unknown point below each field. This was followed by the risk-taking task in which they decided whether to send a tank across each of the fields. The participants were tested on the risk-taking task once in Experiment 1 and over four separate sessions in Experiment 2. Scores, based on decision outcomes, and decision latencies were recorded. No significant sex differences were found in the participants' ability to estimate probabilities or in their total scores for decisions made on the risk-taking task. In low probability-of-success situations, women initially took greater risks than men but took longer...

Identification of Plasmodium vivax sporozoites in mosquitoes using an enzyme-linked immunosorbent assay.

Abstract: A sandwich enzyme-linked immunosorbent assay (ELISA) for identifying Plasmodium vivax sporozoites in mosquitoes is described. Monoclonal antibodies produced against Thailand P. vivax sporozoites were used in an ELISA to detect and identify homologous sporozoites of Southeast Asian, Mexican and North Korean origin in extracts of frozen or dried infected mosquitoes. The assay was sensitive enough to detect 1 infected mosquito in a pool of 20 insects or 125-250 sporozoites per 30 microliter of mosquito extract. The use of a nonionic detergent and a single freeze-thaw to disrupt the circumsporozoite antigen significantly increased the sensitivity of the method.

Navier-Stokes computations of projectile base flow with and without mass injection

Abstract: A computational capability has been developed for predicting the flowfield about projectiles, including the recirculatory base flow at transonic speeds. In addition, the developed code allows mass injection at the projectile base and hence is used to show the effects of base bleed on base drag. Computations have been made for a secant-ogive-cylinder projectile for a series of Mach numbers in the transonic flow regime. Computed results show the qualitative and quantitative nature of base flow with and without base bleed. Base drag is computed and compared with the experimental data and semiempirical predictions. The reduction in base drag with base bleed is clearly predicted for various mass injection rates. Results are also presented that show the variation of total aerodynamic drag both with and without mass injection for Mach numbers of 0.9 < M< 1.2. The results obtained indicate that, with further development, this computational technique may provide useful design guidance for projectiles. MAJOR area of concern in shell design is the accurate prediction of the total aerodynamic drag. Both the range and terminal velocity of a projectile (two critical factors in shell design) are directly related to the total aerodynamic drag. The total drag for projectiles can be divided into three components: 1) pressure drag (excluding the base region), 2) viscous (skin friction) drag, and 3) base drag. At transonic speeds, base drag constitutes a major portion of the total drag. For a typical shell at M = 0.90, the relative magnitudes of the aerodynamic drag components are: 20% pressure drag, 30% viscous drag, and 50% base drag. The critical aerodynamic behavior of projectiles, indicated by rapid changes in the aerodynamic coefficients, occurs in the transonic speed regime and can be attributed in part to the complex shock structure existing on projectiles at transonic speeds. Therefore, in order to predict the total drag for projectiles, computation of the full flowfield (including the base flow) must be made. There are few reliable semiempirical procedures that can be used to predict shell drag; however, these procedures cannot predict the effects of mass injection. The objective of this research effort was to develop a numerical capability, using the Navier-Stokes computational technique, to compute the flowfield in the base region of projectiles at transonic speeds and thus to be able to compute the total aerodynamic drag with and without mass injection. The pressure and viscous components of drag generally cannot be reduced significantly without adversely affecting the stability of the shell. Therefore, recent attempts to reduce the total drag have been directed toward reducing the base drag. A number of studies have been made to examine the total drag reduction due to the addition of a boattail.1 Although this is very effective in reducing the total drag, it has a negative impact on the aerodynamic stability, especially at transonic

Internal and near-surface scattered field of a spherical particle at resonant conditions

Abstract: On presente quelques caracteristiques generales apparaissant dans les conditions de resonance dans la distribution d'intensite du champ a l'interieur des particules spheriques diffusantes et dans le champ proche et la forte augmentation de l'intensite du champ dans le champ proche juste a l'exterieur de la sphere

Endemic Lassa fever in Liberia. IV. Selection of optimally effective plasma for treatment by passive immunization.

Abstract: The efficacy of passive immunization for treatment of Lassa Fever (LF) is believed to depend on the titre of the neutralizing antibody infused. For the purpose of identifying optimal donors of LV-immune plasma, a population of LF-convalescent patients in Liberia was tested for prevalence of neutralizing antibody. Minimally protective titres, expressed as a log10 neutralization index, (LNI), were established in animal models as LNI greater than 2. LNI titres for 26 donors, tested eight or more months after illness, were modest: 16 titred 1 less than LNI less than 2, 4 titred 2 greater than LNI less than 3, and only 4 titred LNI greater than 3. Sequentially obtained plasma from six donors indicated that the LNI response was delayed relative to the indirect fluorescent antibody (IFA) response, that high titres (LNI greater than 3) occurred only after seven months and in only two of six patients. Most of the unselected LV-immune plasma will require concentration to therapeutically useful LNI titres. In a passive immunization experiment, guinea-pigs were protected by a late convalescent plasma (LNI = 4.8, IFA = 320) but not by an early plasma, (LNI = 0.6, IFA = 640), thus supporting the selection of immune plasma on the basis of the LNI. Cross serological testing with LV strains and convalescent plasma from patients in Sierra Leone, Liberia and Nigeria suggested that these LV strains were indistinguishable by cross-IFA, but were readily distinguishable by cross neutralization tests. Geographical matching of LV and plasma origins may thus be a factor in selection of optimal plasma for passive immunization of Lassa fever.

Upper airway sequelae in burn patients requiring endotracheal intubation or tracheostomy.

Abstract: During a period of 11 1/2 months, 41 of 217 adult burn patients admitted to the U.S. Army Institute of Surgical Research Burn Center required endotracheal intubation or tracheostomy for management of the airway and/or ventilatory assistance. Permanent upper airway sequelae were recorded and related to presence of inhalation injury, duration of tube placement, cuff pressure, and pulmonary compliance. An "inhalation injury scoring system" based upon history, physical examination, bronchoscopic findings, and abnormalities at 133xenon lung scan correlated well with postinjury alteration in compliance and subsequent sequelae. Significant inhalation injury was found in 35 patients. Seventeen of the study patients survived (Group I) and 24 patients expired (Group II). Group I patients were screened for permanent airway sequelae by fiberoptic bronchoscopy, xeroradiograms, and spirometry undertaken an average of 11 weeks after extubation or decannulation. Four patients developed tracheal stenosis and five patients had significant tracheal scar granuloma formation. Sequelae were generally more frequent and more severe after tracheostomy than after translaryngeal intubation, and duration of tube placement and presence of a tracheal stoma were the most important etiological factors in permanent damage. For initial respiratory support, we favor the use of translaryngeal (nasotracheal) tubes for periods up to 3 weeks. Fiberoptic bronchoscopic examination is the most reliable follow-up method for detecting anatomic damage in such patients. Spirometry can be used as a noninvasive screening test and xeroradiograms are helpful in assessing the degree of tracheal stenosis.

The Effects of Retelling Upon Reading Comprehension and Recall of Text Information

Abstract: This study investigated the effects of retelling (free recall) upon the comprehension and recall of text information for 93 fourth-grade students. Subjects were assigned randomly to one of two generative learning strategy treatment conditions: retelling or illustrating. Subjects participated in four training sessions and one test session. For each of the four training sessions subjects silently read a passage and then, according to treatment condition, either retold the important parts of the passage or illustrated the important parts of the passage. For the test passage all subjects silently read the passage, and then rendered a free recall. Two days later all subjects rendered a delayed free recall and answered 10 literal and 10 inferential questions about the test passage. Statistically significant differences were found on all measures of reading comprehension and recall (immediate free recall, two-day delayed free recall, and responses to literal and inferential questions) in favor of the sub...

Modification of Sand Fly Biting Behavior by Leishmania Leads to Increased Parasite Transmission

Abstract: To attempt rodent-sand fly-rodent transmission of Leishmania major, laboratory-reared Phlebotomus doboscqi were fed on L. major-infected mice and then refed on uninfected mice 21 days later. Flies which refed either probed 1-2 times and took a full blood meal in less than 10 min or probed 3 or more times and took little or no blood during a period of 15 min or more. When dissected, 7 of 8 flies which experienced difficulty in obtaining a blood meal had flagellates in their cibaria, an observation supporting the hypothesis that parasites in this part of the alimentary canal modify normal blood feeding behavior. None of the infected females which probed 1-2 times had similar anterior station infections. Infected sand flies transmitted L. major to uninfected mice and a single fly, transferred from 1 mouse to the next while repeatedly attempting to take blood, infected 5 mice. During a year-long survey in Baringo District, Kenya, we collected 9,182 female sand flies. Only 2 of the 278 P. duboscqi captured during this collection were infected with L. major; however, 18 of the 789 small rodents from this area were infected with L. major. Parasite interference with normal blood feeding may explain how a relatively small population of P. duboscqi, only a few of which are infected with L. major, can amplify parasite transmission thereby maintaining a disproportionately large reservoir in local rodents.

Visceral leishmaniasis unresponsive to antimonial drugs. II. Response to high dosage sodium stibogluconate or prolonged treatment with pentamidine.

Abstract: Ten Kenyan patients with visceral leishmaniasis unresponsive to sodium stibogluconate, at a dose of 16 to 20 mg Sb/kg body-weight/day given for 30 to 98 days, were treated with 20 mg Sb/kg bw given every eight hours. This regimen was modified or abandoned in six patients because of suspected toxicity, although toxicity was difficult to assess because of intercurrent illness. Toxic effects included lethargy, anorexia, vomiting, electrocardiographic changes, fall in haemoglobin and rise in liver enzymes. One patient died, probably from a cardiac arrhythmia. Two patients were cured, four responded partially and four showed no response. Pentamidine, at a dose of 4 mg/kg body-weight given one to 3 times per week for 5 to 39 weeks, was given as initial treatment in one patient and after failure of sodium stibogluconate in seven. Toxic effects included nephritis, hepatitis, transient diabetes and subcutaneous abscesses. Two patients were cured, two responded partially, three showed no response and one, after apparent cure, relapsed and was unresponsive to additional pentamidine treatment. Low-frequency, long-duration pentamidine was often useful in maintaining any improvement made during treatment with the less well tolerated high-dose, high frequency sodium stibogluconate. We observed the step-wise development of resistance to both sodium stibogluconate and pentamidine. The problems of managing patients with visceral leishmaniasis which is unresponsive to conventional doses of pentavalant antimonials are discussed and some tentative suggestions put forward.

Visceral leishmaniasis unresponsive to antimonial drugs III. Successful treatment using a combination of sodium stibogluconate plus allopurinol

Abstract: Five patients with long-standing visceral leishmaniasis who were unresponsive to sodium stibogluconate, 20 mg antimony/kg body-weight once or twice daily, were treated for 14 to 54 days with a combination of sodium stibogluconate at the same dose plus allopurinol at a dose of 20 mg/kg body-weight per day in three divided doses. This combination was safe and effective. Negative splenic aspirate smears were obtained from all patients within 19 days, and none has relapsed in at least 12 months of follow-up.