Showing papers by "University of Miami published in 1978"

Modern Molecular Photochemistry of Organic Molecules

Abstract: 1. Molecular Photochemistry of Organic Compounds: An Overview 2. Electronic, Vibrational, and Spin Configurations of Electronically Excited States 3. Transitions between States: Photophysical Processes 4. Radiative Transitions between Electronic States 5. Photophysical Radiationless Transitions 6. A Theory of Molecular Organic Photochemistyr 7. Energy Transfer and Electron Transfer 8. Mechanistic Organic Photochemistry 9. Photochemistry of Carbonyl Compounds 10. Photochemistry of Olefins 11. Photochemistry of Enones and Dienones 12. Photochemistry of Aromatic Molecules 13. Supramolecular Organic Photochemistry 14. Molecular Oxygen and Organic Photochemistry 15. A Generalization of the Photochemistry of Organic Molecules Index

Philosophy of logics

Abstract: The first systematic exposition of all the central topics in the philosophy of logic, Susan Haack's book has established an international reputation (translated into five languages) for its accessibility, clarity, conciseness, orderliness, and range as well as for its thorough scholarship and careful analyses. Haack discusses the scope and purpose of logic, validity, truth-functions, quantification and ontology, names, descriptions, truth, truth-bearers, the set-theoretical and semantic paradoxes, and modality. She also explores the motivations for a whole range of non-classical systems of logic, including many-valued logics, fuzzy logic, moddal and tense logics, and relevance logics. Persupposing only an elementary knowledge of formal logic, this book includes many useful summary tables and diagrams, as well as a helpful glossary of technical terms. Wide-ranging, informative, and eminently readable, this book has proven a valuable resource for generations of students and scholars in a variety of disciplines outside philosophy needing guidance on the philosophy of logic.

Removal of atmospheric effects from satellite imagery of the oceans.

Abstract: In attempting to observe the color of the ocean from satellites, it is necessary to remove the effects of atmospheric and sea surface scattering from the upward radiance at high altitude in order to observe only those photons which were backscattered out of the ocean and hence contain information about subsurface conditions. The observations that (1) the upward radiance from the unwanted photons can be divided into those resulting from Rayleigh scattering alone and those resulting from aerosol scattering alone, (2) the aerosol scattering phase function should be nearly independent of wavelength, and (3) the Rayleigh component can be computed without a knowledge of the sea surface roughness are combined to yield an algorithm for removing a large portion of this unwanted radiance from satellite imagery of the ocean. It is assumed that the ocean is totally absorbing in a band of wavelengths around 750 nm and shown that application of the proposed algorithm to correct the radiance at a wavelength lambda requires only the ratio () of the aerosol optical thickness at lambda to that at about 750 nm. The accuracy to which the correction can be made as a function of the accuracy to which can be found is in detail. A possible method of finding from satellite measurements alone is suggested.

Recording from the body surface of arrhythmogenic ventricular activity during the S-T segment.

Abstract: Recent experimental reports have documented the delay of epicardial potentials beyond the QRS complex as a result of infarction, and the degree of delay was directly associated with the onset of ventricular arrhythmias. This study describes a method using high amplification, band pass filtering and signal averaging for recording from the body surface these delayed potentials presaging ventricular arrhythmias. This technique, has been used for recording low level cardiac potentials masked by noise. In 10 dogs control records of the electrocardiogram and surface averaged lead were obtained during sinus rhythm, atrial pacing and premature atrial beats. Subsequently, the left anterior descending coronary artery was ligated in each dog. Nine dogs survived the surgical procedure and underwent similar recordings 3 to 6 days after infarction. Electrocardiographic changes were consistent with a recent infarction. During the pacing protocol discrete multiphasic wave forms appeared during the S-T segment of the surface averaged lead, and concomitant changes in the terminal portions of the QRS complex were observed in seven dogs. In five of these dogs ventricular arrhythmias were observed at the faster pacing rates or after closely coupled premature atrial beats. The chest was then reopened and the pacing procedure repeated during recording of direct epicardial electrograms with a multicontact bipolar electrode. This electrogram validated the existence of potentials during the S-T segment in all but one dog and late activity that was not repeatable on a beat to beat basis in another. Thus, when late activity was confirmed with the epicardial electrogram, seven of eight dogs showed a corresponding change in the surface averaged lead. This technique may prove to be a sensitive indicator of abnormal electrical activity preceding ventricular arrhythmias.

Isolation and culture of pulmonary artery endothelial cells.

Abstract: It has become increasingly evident that endothelial cells function as far more than a mechanical barrier between blood and parenchyma. Endothelial cells from one vesicular bed are known to differ structurally from those of another, and it has been suggested that they may differ functionally. Further to test the hypothesis that endothelial cells from one site may differ in terms of function from those of another site, it is necessary to test endothelium from various source after having obtained these cells in pure, well-characterized cultures. To facilitate such studies, we herein describe in detail means for the isolation, culture and characterization of endothelial cells from calf pulmonary artery. These cells may be of major interest in terms of specific metabolic activities as it has become evident that the lungs play a prominent role in determining the hormonal composition of systemic arterial blood.

Low-magnesian calcite limestones forming at the deep-sea floor, Tongue of the Ocean, Bahamas

Abstract: Carbonate ooze in the deep troughs between the Bahama Banks is a mixture of pelagic and bank-derived material It consists of aragonite, calcite and magnesium calcite in a ratio of about 3:2:1 Where exposed in erosional cuts at the sea floor, this ooze lithifies within 100,000 years and is transformed into calcite micrite of only 35-5 mol % MgCO3 Where buried, the ooze maintains its original composition for at least 200,000-400,000 years and remains unlithified for tens of millions of years Quite unexpectedly, the path of sea-floor diagenesis of peri-platform ooze was found to be the same as that of freshwater diagenesis Most of the aragonite is leached, pteropod shells often leaving cement-lined moulds behind; magnesian calcite recrystallizes and loses magnesium; polyhedral calcite of 2-4 μm size appears as cement The setting and the carbon-oxygen isotope ratios rule out any freshwater influence Carbon isotope ratios remain heavy, oxygen ratios shift towards equilibrium with the cold bottom water The calcite cement has 35-5 mol % MgCO3 and can be interpreted as the least soluble form of calcite emerging from alteration at the sea floor or, alternatively, as a direct precipitate from cold sea water The change in the composition of calcite cements with water depth supports the second interpretation In the Bahamas and elsewhere in the world ocean, magnesium in calcite cements decreases from the warm surface waters down to 700-1200 m, ie the boundary between intermediate and cold deep-water masses Below this level, calcite prevails and magnesian calcite and aragonite cements are restricted to semi-enclosed seas with exceptionally warm bottom waters

Cerebrovascular disease in sickle cell anemia: a clinical, pathological and radiological correlation.

Abstract: An opportunity to study cerebrovascular changes in sickle cell anemia (SCA) presented itself when a black child with this disorder died of bihemispheric strokes. Angiography demonstrated severe occlusive vascular disease involving primarily the circle of Willis and major bifurcations of both internal carotid arteries. Collateral circulation to the distal branches of the internal carotid arteries occurred through transdural anastomoses from the external carotid system and via the leptomeningeal route. Perfusion of the basal ganglia was accomplished by vessels arising from the proximal internal carotid arteries. These changes resembled those of Moyamoya disease. Autopsy showed old and recent cerebral infarcts. Two vascular processes were responsible for the arterial occlusions: (1) exuberant intimal hyperplasia, and (2) old and recent thrombi with partial recanalization. The former has been described only once before in SCA. Small vessels in the basal ganglia were exceptionally numerous and dilated. We conclude that intimal hyperplasia within large cerebral arteries may be responsible for infarction and small vessel prliferation in basal ganglia in patients with SCA.

Correlates of Self-Consciousness

Abstract: Examined the relationship between the three subscales of the Self-Consciousness Scale and a variety of other personality dimensions, including measures of reflectivity, self-regulation, and social desirability. Data from six geographically diverse samples (total N = 1395) were presented. In general, both the construct validity and discriminant validity of the subscales were supported. First, private self-consciousness significantly correlated with the Guilford-Zimmerman Thoughtfulness Scale and the Paivio Imagery Scale. Second, all of the self-consciousness subscales were shown to be relatively independent of the social desirability response set. Third, less than 6% of the variance in each self-consciousness subscale was shared with scores on the Self-Monitoring Scale. Finally, the minimal relationships between the self-consciousness subscales and measures of emotionality and test anxiety reported by Carver and Glass (1976) were in general replicated. The low magnitude of the correlations obtained was interpreted as supporting the distinctive contribution of the Self-Consciousness Scale to personality assessment.

Eyes as the center of focus in the visual examination of human faces.

Abstract: An experiment was conducted to determine the degree to which individuals focus upon the eye region of others while visually inspecting their faces. Using an eye-tracking camera, 16 male subjects spent approximately 40% of their looking time focused upon the eye region of facial photographs, with each of the remaining parts of the face being looked at less.

Oxygen and Carbon Isotopic Growth Record in a Reef Coral from the Florida Keys and a Deep-Sea Coral from Blake Plateau

Abstract: Carbon and oxygen isotope analysis through a 30-year (1944 to 1974) growth of Montastrea annularis from Hen and Chickens Reef (Florida Keys) shows a strong yearly variation in the abundances of both carbon-13 and oxygen-18 and a broad inverse relationship between the two isotopes. Normal annual dense bands are formed during the summer and are characterized by heavy carbon and light oxygen. "Stress bands" are formed during particularly severe winters and are characterized by heavy carbon and heavy oxygen. The isotopic effect of Zooxanthellae metabolism dominates the temperature effect on the oxygen-18/oxygen-16 ratio. The isotopic results on the deep-sea solitary coral Bathypsammia tintinnabulum, where Zooxanthellae are nonexistent, indicates that the abundance of the heavy isotopes carbon-13 and oxygen-18 is inversely related to the growth rate, with both carbon and oxygen approaching equilibrium values with increasing skeletal age.

Human urinary kallikrein converts inactive to active renin and is a possible physiological activator of renin.

Abstract: WE have found that human urinary kallikrein converts inactive plasma renin in vitro to an enzyme with renin-like activity. This observation is interesting because renal kallikrein, the presumed precursor of urinary kallikrein1, is thought to be situated in or on cells of the distal convoluted tubule, including the macula densa cells1–3, which are adjacent to the storage site of renin, the juxtaglomerular cells4. Also, human urinary kallikrein is a trypsin-like enzyme of highly restricted specificity5, and although trypsin is capable of activating inactive renin6, we have found that kallikrein is at least 10 times more active. Therefore it seems possible that urinary kallikrein is the in vivo converting enzyme of prorenin and may activate the renin–angiotensin–aldosterone hormonal system, as it participates in sodium and potassium homeostasis4 and in the blood pressure maintenance of a majority of hypertensive patients7.

Observation and Simulation of Storm-Induced Mixed-Layer Deepening

Abstract: Two observed cases of mixed-layer (ML) deepening due to storms are analyzed and simulated. The primary goal is to learn whether the relevant scale velocity in the parameterization of wind-driven deepening is U*, the wind stress friction velocity, or δV, the magnitude of the horizontal mean velocity difference across the base of the ML. ML deepening is isolated from air–sea exchange and horizontal advection by diagnosing the entrainment tendency of ML temperature. ML deepening is found to be highly intermittent on the storm time scale. Deepening in response to a wintertime atmospheric cold front occurred as δV was accelerated during the initial rise in wind stress. Deepening abruptly ceased as wind stress began to decelerate δV, though the stress magnitude continued to increase. A similar relationship between wind stress δV and ML deepening was also observed in a summertime case and is evidence that the relevant scale velocity is δV not U*. In both cases the observed phase and extent of ML deepeni...

Brazilian pepper—Its impact on people, animals and the environment

Abstract: Native to Brazil,Schinus terebinthifolius Raddi, of the family Anacardiaceae, has been commonly cultivated in Florida for over 50 years as a dooryard ornamental. Use of its sprays of showy red fruits for Christmas decoration gave rise to the popular misnomer “Florida holly.” Too late it was found to become a large, spreading tree; aggressive seedlings began springing up near and far. Jungles ofSchinus have crowded out native vegetation over vast areas of Florida and the Bahamas, as in all the islands of Hawaii. When in bloom, the tree is a major source of respiratory difficulty and dermatitis; the fruits, in quantity, intoxicate birds and cause fatal trauma in four-footed animals. The abundant nectar yields a spicy commercial honey and beekeepers are opposed to eradication programs.

Saccadic system plasticity in humans.

Abstract: A subject with a medial rectus paresis secondary to a partial third nerve palsy was forced to use the affected eye for six days while the good eye was constantly patched. Saccadic eye movements were carefully measured each day; the grain increased, with a time constant of 0.85 day. The patch was then switched to the paretic eye and the gain decreased, with a time constant of 0.85 day. The patch was then switched to the paretic eye and the gain decreased, with a time constant of 1.54 days. This demonstrated central nervous system plasticity of the pulse and step of neural activity responsible for the generation of saccades in the adult human. In addition to gain changes, postsaccadic drift velocity and saccadic velocity/amplitude relationship alterations during the patching are reported. A major conclusion that can be drawn from analysis fo these data is that the gain changing is accomplished by pulse width changes rather than pulse height (firing frequency), which was not markedly altered.

Intracellular pH, intracellular free Ca, and junctional cell-cell coupling.

Abstract: Intracellular pH (pH i ) and intracellular Ca2+ ([Ca2+] i ) were determined inChironomus salivary gland cells under various conditions of induced uncoupling. pH i was measured with aThomas-type microelectrode, changes in [Ca2+] i and their spatial distribution inside the cell were determined with the aid of intracellularly injected aequorin and an image intensifier-TV system, and cell-to-cell coupling was measured electrically. Treatments with NaCN (5mm), DNP (1.2mm), or ionophore A23187 (2μm) caused fall in junctional conductance (uncoupling) that was correlated with [Ca2+] i elevation, as was shown before (Rose & Loewenstein, 1976,J. Membrane Biol. 28:87) but not with changes in pH i : during the uncoupling induced by CN, the pH i (normally ≈ 7.5) decreased at most by 0.2 units; during the uncoupling induced by the ionophore, pH i fell by 0.13 or rose by 0.3; and in any one of these three agents' uncouplings, the onset of uncoupling and recovery of coupling were out of phase with the changes in pH i . Intracellular injection of Ca-citrate or Ca-EGTA solutions buffered to pH 7.2 or 7.5 produced uncoupling with little or no pH i change when their free [Ca2+] i was >10−5 m. On the other hand, such a solution at pH 4, buffered to [Ca2+]<10−6 m, lowered pH i to 6.8 but produced no uncoupling. Thus, a decrease in pH i is not necessary for uncoupling in any of these conditions. In fact, uncoupling ensued also during increase in pH i : exposure to NH4HCO3 or withdrawal of propionate following exposure to a propionate-containing medium caused pH i to rise to 8.74, accompanied by [Ca2+] i elevation and uncoupling at pH i >7.8. Cell acidification itself can cause elevation of [Ca2+] i : injection (iontophoresis) of H+ invariably caused [Ca2+] i elevation and uncoupling. These effects were produced also by an application of H+-transporting ionophore Nigericin at extracellular pH 6.5 which caused pH i to fall to 6.8. Exposure to 100% CO2 produced a fall in pH i , associated in 10 out of 25 cases with [Ca2+] i elevation and, invariably, with uncoupling. The absence of a demonstrable [Ca2+] i elevation in a proportion of these trials is attributable to depression in Ca2+-measuring sensitivity; inin vivo tests, detection sensitivity for [Ca2+] i by aequorin was found to be depressed by the CO2 treatment. Upon CO2 washout, pH i and coupling recovered, but onset of recoupling set in at pH i as low as 6.32–6.88, generally lower than at the pH i at which uncoupling had set in. Exposure to 5% CO2 lowered pH i on the average by 0.3 and depressed coupling (in initially poorly coupled cells). After CO2-washout, pH i and coupling recovered. During the recovery phase [Ca2+] i was elevated, an elevation associated with renewed uncoupling or decrease in rate of recoupling. The results are discussed in connection with possible regulatory mechanisms of junctional permeability.

The Treatment of Idiopathic Thrombocytopenia with Vinblastine-Loaded Platelets

Abstract: We devised a method to enhance delivery of vinblastine to macrophages, the cells believed to be responsible for platelet destruction in idiopathic thrombocytopenic purpura. Our strategy was based on the ability of platelets to bind vinca alkaloids such as vinblastine. Platelets were incubated with an excess of vinblastine, concentrated and then, after excess alkaloid had been removed, given to 11 patients with idiopathic thrombocytopenia refractory to other treatment (including intravenous injections of vinca alkaloids). Platelet antibodies in the patients' plasma led to ingestion of the vinca-laden platelets by macrophages. There were six complete remissions, three partial remissions and two failures. Side effects in a few patients, reversible but annoying, were minimized as technics were refined. We conclude that in patients with idiopathic thrombocytopenia refractory to all other measures, including the use of vinca alkaloids, platelet-vinca complex may be effective.

Traumatic retinopathy in primates. The explanation of commotio retinae.

Abstract: • We have produced experimental commotio retinae in 12 owl monkeys by blunt trauma. The ophthalmoscopic and fluorescein angiographic appearance of this contrecoup lesion is identical to the acute traumatic retinal opacity in humans. We examined these eyes by light and electron microscopy from 4 hours to 12 weeks after injury. Immediately after injury, the only abnormality is disruption of the receptor outer segments. From one to six days after trauma, many receptor cells undergo degeneration. The retinal pigment epithelium phagocytoses the degenerating outer segments, occasionally migrating into the retina. There is no extracellular retinal edema. The opacity of commotio retinae seems to represent disrupted receptor cells. Visual loss may result from permanent loss of receptors. The pigment epithelial response to traumatic receptor damage is similar to that observed in experimental retinal detachment and light-induced retinal damage.