Showing papers by "University of Miami published in 1980"
TL;DR: The concentration of airborne soil dust at Enewetak Atoll in April 1979 was 2.3 micrograms per cubic meter but decreased steadily to 0.02 microgramper cubic meter over the next 5 months, suggesting that the spring dust is probably derived from China.
Abstract: The concentration of airborne soil dust at Enewetak Atoll(11°N, 162°E) in April 1979 was 2.3 micrograms per cubic meter but decreased steadily to 0.02 microgram per cubic meter over the next 5 months. The spring dust is probably derived from China; its deposition rate (∼0.3 millimeter per 1000 years) suggests that it may be a significant contributor to the deep-sea sediments of the North Pacific.
805 citations
TL;DR: This paper presents the state-of-the-art in human factors in flight-deck automation, identifies a number of critical problem areas, and offers broad design guidelines.
Abstract: Modern microprocessor technology and display systems make it entirely feasible to automate many of the flight-deck functions previously performed manually. There are many benefits to be derived from automation; the question today is not whether a function can be automated, but whether it should be, due to various human factors issues. It is highly questionable whether total system safety is always enhanced by allocating functions to automatic devices rather than human operators, and there is some reason to believe that flight-deck automation may have already passed its optimum point. This is an age-old question in the human factors profession, and there are few guidelines available to the system designer. This paper presents the state-of-the-art in human factors in flight-deck automation, identifies a number of critical problem areas, and offers broad design guidelines. Some automation-related aircraft accidents and incidents are discussed as examples of human factors problems in automated flight.
593 citations
TL;DR: In this paper, the authors discuss two dimensions of bicultural involvement and report on the development and validation of a biculturalism and a cultural involvement scale for operationalizing both of these dimensions.
547 citations
TL;DR: During a nine-year period ending in 1977, scraped and cultured 663 corneal ulcers, and Pseudomonas was the predominant bacterial organism, and Fusarium was the most common fungus isolated.
464 citations
TL;DR: It is shown that a general increase in adherence does not correlate well with the rapid turning response observed in this study, and the hypothesis that intracellular levels of cAMP and /or cGMP and calcium may play a role in the turning response of dorsal root neurites toward NGF is questioned.
Abstract: This study reports that chick dorsal root ganglion neurites undergo a rapid (20 min) reorientation of their direction of growth in response to nerve growth factor (NGF) concentration gradients in vitro. Dorsal root ganglia from chick embryos were explanted onto a collagen-poly-L-lysine substrate. After 24-48 h in culture, NGF gradients were applied to individual growth cones via a micropipette containing 50 biological units NGF/ml. The growth cones turned and grew toward these NGF sources. This turning response was not caused by the trophic effects of NGF on neurite initiation, survival, or growth rate. Dorsal root neurites also grew toward sources of mono- and dibutyryl cyclic adenosine monophosphate (dB cAMP), cyclic guanosine monophosphate (cGMP), and elevated calcium in the presence of the calcium ionophore A23187. These results are consistent with the hypothesis that intracellular levels of cAMP and /or cGMP and calcium may play a role in the turning response of dorsal root neurites toward NGF, but do not establish a causal relationship between the mechanisms of action of NGF, cyclic nucleotides and calcium. Total growth cone adherence to the substrate was measured using a timed microjet of perfusion medium. NGF increased the adherence of growth cones to the substrate, but caffeine and dB cAMP which also elicit the positive turning response, decreased growth cone adherence. Calcium, which did not elicit the positive turning response, produced a greater growth cone adherence to the substrate than that observed with NGF. Although these results do not rule out a role of adhesion changes in axonal turning to NGF, they show that a general increase in adherence does not correlate well with the rapid turning response observed in this study.
437 citations
TL;DR: For example, during three major Saharan dust outbreaks as they passed across the tropical North Atlantic Ocean during the summer of 1974, the dominant mineral group was mica-illite; the mean concentration at each station ranged from 54% at Sal Island to 64% at Barbados and Miami, Florida as mentioned in this paper.
415 citations
TL;DR: Treatment is indicated for eyes exhibiting progressive disc cupping, even in the absence of visual field defects, because typical glaucomatous field loss developed in 50% during a follow-up of one to six years (average, two years).
Abstract: Serial disc photographs of 259 patients with elevated intraocular pressures were studied retrospectively up to 15 years. Twenty-nine eyes showed progressive enlargement of the optic cup. Early vertical extension of the cup occurred in vertical extension of the cup occurred in five eyes and horizontal extension in one. In 23 eyes, a generalized expansion of the cup (retaining its round appearance) was the first change observed, typically preceding visual field loss by several years. Thus, serial disc photographs are necessary for the earliest detection of optic nerve damage in ocular hypertension. Of 18 eyes with normal visual fields at the time progression of cupping was first noted, typical glaucomatous field loss developed in 50% during a follow-up of one to six years (average, two years). Therefore, treatment is indicated for eyes exhibiting progressive disc cupping, even in the absence of visual field defects.
400 citations
TL;DR: Initial imagery confirms that CZCS data can be processed to a level that reveals subtle variations in the concentration of phytoplankton pigments, which has potential applications for the study of large-scale patchiness in phy toplankon distributions, the evolution of spring blooms, water mass boundaries, and mesoscale circulation patterns.
Abstract: The Coastal Zone Color Scanner (CZCS) on Nimbus-7, launched in October 1978, is the only sensor in orbit that is specifically designed to study living marine resources. The initial imagery confirms that CZCS data can be processed to a level that reveals subtle variations in the concentration of phytoplankton pigments. This development has potential applications for the study of large-scale patchiness in phytoplankton distributions, the evolution of spring blooms, water mass boundaries, and mesoscale circulation patterns.
388 citations
TL;DR: The removal of atmospheric effects from Nimbus-7 Coastal Zone Color Scanner (CZCS) images reveals eddy-like ocean turbidity patterns not apparent in the original calibrated images.
Abstract: The removal of atmospheric effects from Nimbus-7 Coastal Zone Color Scanner (CZCS) images reveals eddy-like ocean turbidity patterns not apparent in the original calibrated images. Comparisons of the phytoplankton pigment concentrations derived from the corrected CZCS radiances with surface measurements agree to within less than 0.5 log C, where C is the sum of the concentrations of chlorophyll a plus phaeopigments a (in milligrams per cubic meter).
347 citations
TL;DR: The preterm infants of teenage mothers who received intervention showed more optimal growth, Denver scores, and face-to-face interactions at 4 months, and their mothers rated their infants' temperaments more optimally, expressed more realistic developmental milestones and child-rearing attitudes, and received higher ratings on face- to- face interactions.
Abstract: To assess the combined risks of being born preterm and to a teenage mother, and to evaluate the effects of an early intervention, preterm infants born to lower-class, black, teenage mothers were provided a home-based, parent-training intervention, and their development was then compared with that of nonintervention controls, of term infants of teenage mothers, and of term and preterm infants of adult mothers. Despite equivalence on prenatal care, factors which placed the preterm infant of the teenage mother at greater risk at birth were the small-for-date size of the infant and the less realistic developmental milestones and child rearing attitudes expressed by the mother. The preterm infants of teenage mothers who received intervention showed more optimal growth, Denver scores, and face-to-face interactions at 4 months. Their mothers rated their infants' temperaments more optimally, expressed more realistic developmental milestones and child-rearing attitudes, and received higher ratings on face-to-face interactions. At 8 months, the intervention group received superior Bayley mental, Caldwell, and infant temperament scores.
334 citations
TL;DR: Data from nine beagle dogs are interpreted to mean that the dental follicle may influence, if not coordinate, these processes in tooth eruption.
Abstract: The roles of the gubernaculum dentis, root formation, tooth crown and dental follicle in prefunctional eruption of a mandibular premolar have been studied in nine beagle dogs by radiographic and histologic evaluations of the effects of surgical ablation or removal of these structures on tooth eruption. The dental follicle was the only one of these structures required for the coordinated enlargement of the eruption pathway and formation of bone in the base of the bony crypt, the radiographic and histologic hallmarks of tooth eruption. These data, together with the topographic relationships of the dental follicle to areas of localized bone resorption and formation, are interpreted to mean that the dental follicle may influence, if not coordinate, these processes in tooth eruption.
TL;DR: Six infants with a neonatally lethal malformation syndrome of hypothalamic hamartoblastoma, postaxial polydactyly, and imperforate anus are reported on, postulated that this is a previously apparently unreported syndrome of presently unknown cause.
Abstract: We report on six infants with a neonatally lethal malformation syndrome of hypothalamic hamartoblastoma, postaxial polydactyly, and imperforate anus Some, but not all, patients had laryngeal cleft, abnormal lung lobulation, renal agenesis and/or renal dysplasia, short 4th metacarpals, nail dysplasia, multiple buccal frenula, hypoadrenalism, microphallus, congential heart defect, and intrauterine growth retardation The infants also had hypopituitarism and hypoadrenalism
All were sporadic cases, parents were not consanguineous, chromosomes were apparently normal Family histories were unremarkable There was insecticide and/or herbicide exposure in several of the cases, but no exposures were common to all 6 mothers Five of the patients were born within an 8-month period, but all in different geographic locations It is postulated that this is a previously apparently unreported syndrome of presently unknown cause
TL;DR: It is still not clear how many patients can be salvaged by treatment to extended paraaortic radiation fields, but longer periods of follow-up in patients whose treatment plans were based on surgical staging information will be required.
TL;DR: The present procedure results in highly rapid and sensitive visualization of dopamine-, noradrenaline- and serotonin-containing neurons and their axonal varicosities.
TL;DR: Postmortem studies of three ostensibly healthy persons whose unheralded death occurred incidental to strenuous exercise revealed an unobstructed but mural left anterior descending (LAD) artery, diminished vascularity to the posterior left ventricle and ventricular septum, and morphologic evidence of patchy, ischemic necrosis of the vents in different stages of healing.
Abstract: Postmortem studies of three ostensibly healthy persons whose unheralded death occurred incidental to strenuous exercise revealed an obstructed but mural left anterior descending (LAD) artery, diminished vascularity to the posterior left ventricle and ventricular septum, and morphologic evidence of patchy, ischemic necrosis of the ventricular septum in different stages of healing. Although mural coronary arteries are considered a normal anatomic variant, our observations, coupled with reported clinical studies, strongly suggest that systolic constriction of the LAD artery may precipitate death in selected subjects.
TL;DR: Vision of 20/20 to 20/400 was achieved in 57% of recently operated, culture-positive eyes treated with intraocular antibiotics, and in 59% of those treated with combined vitrectomy and intraoculariotics.
01 Apr 1980
TL;DR: A new high pressure equation of state for water and seawater has been derived from the experimental results of Millero and coworkers in Miami and Bradshaw and Schleicher in Woods Hole as mentioned in this paper.
Abstract: A new high pressure equation of state for water and seawater has been derived from the experimental results of Millero and coworkers in Miami and Bradshaw and Schleicher in Woods Hole The form of the equation of state is a second degree secant bulk modulus
K = Pv0(v0−vp=K0+AP+BP2
K = Kw0+aS+bS32
A = Aw+cS+dS32
B = Bw+eS
where ν0 and νP are the specific volume at 0 and P applied pressure and S is the salinity (ℵ) The coefficients KWO, AW, and BW for the pure water part of the equation are polynomial functions of temperature The standard error of the pure water equation of state is 43 × 10−6 cm3 g−1 in νWP The temperature dependent parameters a, b, c, d, and e have been determined from the high pressure measurements on seawater The overall standard error of the seawater equation of state is 90 × 10−6 cm3 g−1 in νP Over the oceanic ranges of temperature, pressure, and salinity the standard error is 50 × 10−6 cm3 g−1 in νP This new high pressure equation of state has recently (1979) been recommended by the UNESCO Joint Panel on Oceanographic Tables and Standards for use by the oceanographic community
TL;DR: In this paper, Linoleic acid was used to correct the defect in barrier function of essential fatty acid deficiency in EFA-deficient rodents, which can either reflect a prostaglandin-mediated return toward normal epidermal differentiation, or, instead, a direct effect of linoleic acids.
TL;DR: A method for measuring DNA in tissue cells by flow cytometry utilizing a one step combination nuclear isolation-DNA fluorochrome staining procedure is described, using a variety of cells and tissues to illustrate the universal nature of this technique.
Abstract: A method for measuring DNA in tissue cells by flow cytometry utilizing a one step combination nuclear isolation-DNA fluorochrome staining procedure is described. A variety of cells and tissues, both in vivo and in vitro, was used to illustrate the universal nature of this technique. These included murine bone marrow, liver testicle, sarcoma brain tumor, rat pancreatic islets, human peripheral blood, colon mucosa, colon cancer, sarcoma and brain tumor tissues. A special nuclear isolation medium, which contained either of the DNA fluorochromes, 4',6-diamidino-2 phenylindole-2 HCl or propidium iodide, was utilized successfully to isolate single suspensions of DNA fluorochrome stained nuclei in a rapid (5-10 min), consistent manner from a variety of tissues and cells. Multiple sampling of the same tissue or comparison between whole tissues and their single cell isolates showed that a representative sample was being obtained.
TL;DR: Autotransplantation of tissue cultured fibroblasts from rabbit rump skin into the vitreous cavity resulted in intravitreal strand formation and traction retinal detachment and fibroblast growth was inhibited by the significantly reduced number of retinal detachments.
TL;DR: In this paper, phase diagrams for likely chloride and sulfate brines indicate that the minimum temperature at which a brine can be stable is near 210 K with a water concentration of approximately 70 wt % and a high concentration of calcium chloride.
TL;DR: This relatively comprehensive review treats only a limited number of subjects and publications in an attempt to bring the reader more or less up-to-date on the major aspects of developments over the last five years.
Abstract: In the last five years there have been literally hundreds of articles of the world's medical literature regarding sudden infant death syndrome. This work has shed some light on various epidemiologic aspects of the problem, on pathologic anatomy, and on clinical issues such as the relative importance of spontaneous, protracted, idiopathic apnea and prolongation of the Q-T interval. This relatively comprehensive review treats only a limited number of these subjects and publications in an attempt to bring the reader more or less up-to-date on the major aspects of developments over the last five years. Language: en
TL;DR: The basic features of the motoneurone action potential were reconstructed by simulations based on voltage clamp measurements of the voltage dependent conductance systems and previous measurements of passive membrane properties, and indicated that a major portion of the delayed depolarization following the action potential is attributable to capacitative currents from the dendrites.
Abstract: 1. The soma membrane of cat motoneurones was voltage-clamped in vivo using intracellular current and voltage electrodes whose tips were separated by at least 5 micrometer. 2. Depolarization activates two separate, non-interacting K conductance systems whose rates of activation and decay differ by a factor of about 10. These conductances have a similar reversal potential, in the range of -6 to -21 mV (these and all subsequent voltages are expressed relative to the resting potential). Both conductances show linear 'instantaneous' current-voltage relationships. The steady-state magnitudes of both conductances increase with increasing depolarization. Neither conductance inactivates substantially during prolonged depolarizations. 3. The faster K conductance is similar to that described for squid axons and frog node. Activation begins at about +30 mV and is more than 90% complete within 5 msec of a depolarizing voltage step to +50 mV. Activation kinetics appear to be nonlinear. This fast K conductance contributes to the fast falling phase of the action potential. Following repolarization, this conductance decays with a time constant of 2-4 msec. 4. The slower K conductance activates during depolarizations of 10 mV or greater. The activation and decay of this conductance can be described by first-order exponential functions with time constants ranging from 20 to 50 msec. The slow K conductance underlies the prolonged hyperpolarization that follows motoneurone action potentials. Evidence from other studies suggests that this slow K conductance is regulated by intracellular Ca ions. 5. In addition to the two K conductance systems activated by depolarization, motoneurones exhibit another distinct conductance system that is activated by hyperpolarization. This third system has a reversal potential near the resting potential. Activation of this conductance during a hyperpolarizing voltage step can be fitted by a single exponential function with a time constant of 50-60 msec over the range -20 to -50 mV. This hyperpolarization-activated conductance accounts for some aspects of the anomalous rectification reported in cat motoneurones. 6. When the clamp circuit was turned off and the motoneurones were stimulated to discharge repetitively by depolarizing current steps, the apparent soma threshold voltage increased as the applied current (and discharge frequency) increased. 7. The basic features of the motoneurone action potential were reconstructed by simulations based on voltage clamp measurements of the voltage dependent conductance systems and previous measurements of passive membrane properties. These simulations assumed that the kinetics of the fast Na and K conductance systems in motoneurones can be described by equations of the same form as the Hodgkin-Huxley equations. These action potential reconstructions indicated that a major portion of the delayed depolarization following the action potential is attributable to capacitative currents from the dendrites...
TL;DR: It seems that age, by itself, is a poor indicator of health among the elderly; however, how the elderly view their own health may be an extremely useful clinical guide as to their overall health status.
09 May 1980
TL;DR: The geophysical anatomy of the southern Belize continental margin and adjacent basins, including the morphology, sediments and organisms of the deep barrier reef and fore-reef.
Abstract: The geological setting of Belize reefs. The geophysical anatomy of the southern Belize continental margin and adjacent basins. The morphology, sediments and organisms of the deep barrier reef and fore--reef. The Perireefal sediments. The composition and age of limestones from the reef front, wall and fore--reef. Petrography of limestones from the wall and fore--reef. Comparative anatomy, organism distribution and late quaternary evolution of modern reef margins. Sedimentation and diagenesis on the deep seaward margin of modern reefs
TL;DR: New techniques for the culture of pulmonary endothelial cells are developed which avoid exposure to proteolytic enzymes at both the isolation step and during subculture, and which to a large extent determine the scope of biochemical studies which can be undertaken.
Abstract: Enzymes situated along the luminal surface of pulmonary endothelial cells interact with circulating solutes, notably with vasoactive substances, to regulate the hormonal composition of systemic arterial blood. However, it is becoming clear that the range and complexity of reactions occurring at or near the surface of endothelial cells are greater than previously recognized. In addition, evidence indicates that the quality of cell cultures used to define specific endothelial functions must be carefully controlled, together with development of improved understanding of the effects of long-term culture on pulmonary endothelial cells. We have developed new techniques for the culture of pulmonary endothelial cells which avoid exposure to proteolytic enzymes at both the isolation step and during subculture. A combination of mechanical harvest and culture on microcarrier beads has provided a system for the long-term, large-scale culture of pulmonary endothelial cells, features which to a large extent determine the scope of biochemical studies which can be undertaken.
TL;DR: It is reported that GnRH and two potent agonists stimulate meiosis in vitro in follicle-enclosed oocytes in a dose-dependent and specific manner, and also cause an increase of lactate accumulation during incubation.
Abstract: Although the principal function of gonadotropin releasing hormone (GnRH) is to stimulate the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH), there is evidence that agonistic analogues of GnRH directly inhibit steroidogenesis in the testis1 and ovary2–5. On the other hand, Clark et al.6 have demonstrated that GnRH and two agonists have a marked stimulatory effect on prostaglandin synthesis by granulosa cells isolated from immature rats treated with pregnant mare's serum gonadotropin (PMSG). Stimulation by these compounds was distinct from that by LH in that no changes in cyclic AMP production were detected. Thus it seems important to investigate the effect of these peptides on other aspects of ovarian function, for example oocyte maturation. Mammalian oocytes are arrested in the dictyate stage of the first meiotic prophase, and meiosis (oocyte maturation) normally resumes in preovulatory follicles as a consequence of the surge of LH and FSH. This maturation can also be initiated in vitro by the addition of gonadotropins to isolated preovulatory follicles7,8, and is accompanied by an increase in the production of lactate8. We now report that GnRH and two potent agonists9 stimulate meiosis in vitro in follicle-enclosed oocytes in a dose-dependent and specific manner, and also cause an increase of lactate accumulation during incubation.
TL;DR: The findings suggest that during mechanical ventilation the high chestwall compliance and low lung compliance of premature infants prevent a significant rise in intrapleural pressure which could interfere with central venous return and cardiac output.
Abstract: Chestwall compliance was determined in 26 premature infants (BW 1 320 +/- 410 g, gest. age 32 weeks) and in 10 full-term infants (BW 3 155 +/- 810 g) who were ventilated mechanically. Chestwall compliance in premature infants was 6.4 ml/(cmH2O X kg), decreasing with advancing gestational age to 4.2 ml/(cmH20 X kg) in full-term infants. There was a linear correlation (r = 0.95 and 0.79 respectively) between tidal volume and the pressure transmitted to the esophagus throughout the tidal volume range. The protion of airway pressure transmitted to the infants with hyaline membrane disease, 12% in newborns with a patent ductus arterisus, 17% in normal prematures and 25% in normal full-term infants. The findings suggest that during mechanical ventilation the high chestwall compliance and low lung compliance of premature infants prevent a significant rise in intrapleural pressure which could interfere with central venous return and cardiac output. However, using high inspiratory pressures and continuous distending airway pressure in the absence of lung pathology may result in a decreased cardiac output. The highly compliant chestwall of the premature infant may exert insufficient outward recoil and might be one of the causes of a low functional residual capacity and chronic pulmonary failure in the premature infant.