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Showing papers by "Boston University published in 1974"


Journal ArticleDOI
01 Feb 1974-Tellus A
TL;DR: In this paper, the authors present an alternative explanation that early after life began it acquired control of the planetary environment and that this homeostasis by and for the biosphere has persisted ever since.
Abstract: During the time, 3.2 × 10 9 years, that life has been present on Earth, the physical and chemical conditions of most of the planetary surface have never varied from those most favourable for life. The geological record reads that liquid water was always present and that the pH was never far from neutral. During this same period, however, the Earth's radiation environment underwent large changes. As the sun moved along the course set by the main sequence of stars its output will have increased at least 30% and possibly 100%. It may also have fluctuated in brightness over periods of a few million years. At the same time hydrogen was escaping to space from the Earth and so causing progressive changes in the chemical environment. This in turn through atmospheric compositional changes could have affected the Earth's radiation balance. It may have been that these physical and chemical changes always by blind chance followed the path whose bounds are the conditions favouring the continued existence of life. This paper offers an alternative explanation that, early after life began it acquired control of the planetary environment and that this homeostasis by and for the biosphere has persisted ever since. Historic and contemporary evidence and arguments for this hypothesis will be presented. DOI: 10.1111/j.2153-3490.1974.tb01946.x

663 citations


Journal ArticleDOI
TL;DR: The appearance of increased behavioural sensitivity to apomorphine, a putative direct agonist of dopamine receptors in the corpus striatum and limbic system, when non-specific withdrawal effects and changes in the metabolism of catecholamines or of the agonist were unlikely, suggest that the phenomenon of receptor supersensitivity following pharmacologically-induced “denervation” may be involved.

445 citations


Journal ArticleDOI
TL;DR: A prospective study of 2750 employed men who completed a computer-scored test questionnaire measuring the coronary-prone Type A behavior pattern showed that high scorers had twice the incisive risk of heart attack as low scorers.
Abstract: Prospective study of 2750 employed men who completed a computer-scored test questionnaire measuring the coronary-prone Type A behavior pattern showed that high scorers had twice the incide...

396 citations


Journal ArticleDOI
TL;DR: A general theory of subsonic potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented in this article, where an integral representation for the velocity potential is obtained by using the Green function method.
Abstract: A general theory of subsonic potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented. By using the Green function method, an integral representation for the velocity potential is obtained for both supersonic and subsonic flow. Under the small perturbation assumption, the potential at any point in the field depends only upon the values of the potential and its normal derivative on the surface of the body. On the surface of the body, this representation reduces to an integro-differential equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface. The theory is applied to finite-thickness wings in subsonic steady and oscillatory flows.

329 citations


Journal ArticleDOI
01 Feb 1974-Americas
TL;DR: The focus of Braudel's great work is the Mediterranean world in the second half of the sixteenth century, but the focus of this work is not the Mediterranean but the natural world and material life, economics, demography, politics, and diplomacy.
Abstract: The focus of Fernand Braudel's great work is the Mediterranean world in the second half of the sixteenth century, but Braudel ranges back in history to the world of Odysseus and forward to our time, moving out from the Mediterranean area to the New World and other destinations of Mediterranean traders. Braudel's scope embraces the natural world and material life, economics, demography, politics, and diplomacy.

298 citations


Journal ArticleDOI
01 Dec 1974-Cortex
TL;DR: It is suggested that both dominance for music and existence of less developed language areas in the right hemisphere are perhaps being used to support the damaged left hemisphere which continues to be language-dominant.

296 citations


Journal ArticleDOI
TL;DR: The total number of neuroglial cells increases with age, however, the numbers of the various types do not increase by similar proportions and in animals 18 months and older, examples of the multipolar, the elongated, and the engorged spherical forms of microglia may be encountered.
Abstract: Neuroglial cells were examined in the rat auditory cerebral cortex to determine the effects of aging on astrocytes, oligodendrocytes and microglia. The animals ranged in age from 3 months to 29.5 months. Over this age range of 26.5 months none of the neuroglial cells exhibit striking abnormalities in the morphology or the number of their organelles other than each of these cell types accumulates a distinct membrane-bound inclusion material. Astrocytes accumulate considerably more of this material than oligodendrocytes, and demonstrate earlier and more frequent signs of it. Microglia show the most striking alterations in regard to the inclusion material and in animals of increasing age microglial cells engorged with the heterogeneous material become increasingly common. Concurrently there is a slow transformation of the microglial population from an array of multipolar forms to larger, elongated or spherical forms which contain variable amounts of the dense membrane-bound material. These alterations in the microglial cell population do not occur at a chronologically uniform rate, and in animals 18 months and older, examples of the multipolar, the elongated, and the engorged spherical forms of microglia may be encountered. The total number of neuroglial cells increases with age. However, the numbers of the various types do not increase by similar proportions. While there is little change in the populations of astrocytes and oligodendrocytes in rats between the ages of 3 and 27 months, in the same animals the number of microglia increases by about 65%.

293 citations


Journal ArticleDOI
TL;DR: The retina of a mouse embryo on day 13 of gestation, the first day when ganglion cells with axons are detectable, has been studied both qualitatively and quantitatively by reconstructing a large number of cells from an electron microscopic serial section series to construct a simple hypothesis explaining some of the apparently contradictory results of neuronal development.

292 citations


Journal ArticleDOI
TL;DR: The Framingham study has followed a cohort of men and women, aged 29-62 when first seen, for 18 years and found that death and C.H.D. rates among men smoking more than 10 cigarettes a day at entry were distinctly higher as mentioned in this paper.

291 citations



Journal ArticleDOI
TL;DR: The present observations suggest a view of development in terms of the participation of the infant at the outset in multiple forms of interactional organization, rather than as an isolate.
Abstract: CONDON, WILLIAM S., and SANDER, Lours W. Synchrony Demonstrated between Movements of the Neonate and Adult Speech. CHILD DEVELOPMENT, 1974, 45, 456-462. The human neonate moves in precise and sustained synchronous organizations of change of movement with the articulated structure of adult speech as early as the first day of life. This complex and on-going "dance" of the neonate with human speech may necessitate conceptual revisions concerning the nature and functions of neonatal responsivity. In addition, present models of interaction may be found to be inadequate to account for entrainment and synchrony of this order. The present observations suggest a view of development in terms of the participation of the infant at the outset in multiple forms of interactional organization, rather than as an isolate.

Journal ArticleDOI
01 Jun 1974-Cortex
TL;DR: Results from the two experiments suggest that the right hemisphere is directly involved in the perception of intonation contours, and that normal language perception involves the active participation of both cerebral hemispheres.

Journal ArticleDOI
TL;DR: No substantial differences were observed with regard to bleeding, encephalopathy, or hepatic function, although the side-side shunt provided better control of ascites, and published data do not exclude the possibility that a therapeutic portacaval shunt may allow longer survival for the patient with a single major variceal hemorrhage.

Journal ArticleDOI
01 Apr 1974-Icarus
TL;DR: A review of the evidence that the earth's atmosphere is regulated by life on the surface so that the probability of growth of the entire biosphere is maximized can be found in this paper.

Journal ArticleDOI
TL;DR: Data are presented from 27 patients (34 eyes) with central serous choroidopathy who were followed up for an average of 23 months without therapeutic intervention, and the detachment completely resolved in all cases.
Abstract: Data are presented from 27 patients (34 eyes) with central serous choroidopathy who were followed up for an average of 23 months without therapeutic intervention. The detachment completely resolved in all cases. The average duration of detachment was three months. In all eyes, the visual acuity returned to 20/40 or better, and in all but two eyes, the final visual acuity was 20/30 or better. Central serous choroidopathy is essentially a benign and self-limited disorder, and treatment by photocoagulation is seldom needed.

Journal ArticleDOI
01 May 1974-Cancer
TL;DR: Serum CEA was evaluated in 69 patients with breast cancer and 17 with benign breast disease and the trends of serial CEA values correlated with response to treatment.
Abstract: Serum CEA was evaluated in 69 patients with breast cancer and 17 with benign breast disease. Serum CEA was elevated (above 2.5 ng/ml) in 6 of 22 patients (27%) with primary cancer without clinical evidence of distant metastases, and in 37 of the 47 (79%) who had metastatic disease. Sixteen of 17 patients (94%) with benign cystic disease had values less than 2.5 ng/ml (1 was 2.9 ng/ml). Fourteen patients with metastases undergoing chemo- and hormonal therapy were studied by serial CEA estimations for 3 to 18 months, with a mean of 14 months. The trends of serial CEA values correlated with response to treatment.

Journal ArticleDOI
TL;DR: A password scheme is presented which does not require secrecy in the computer and is based on using a function H which the would-be intruder is unable to invert.
Abstract: In many computer operating systems a user authenticates himself by entering a secret password known solely to himself and the system. The system compares this password with one recorded in a Password Table which is available to only the authentication program. The integrity of the system depends on keeping the table secret. In this paper a password scheme is presented which does not require secrecy in the computer. All aspects of the system, including all relevant code and data bases, may be known by anyone attempting to intrude.The scheme is based on using a function H which the would-be intruder is unable to invert. This function is applied to the user's password and the result compared to a table entry, a match being interpreted as authentication of the user. The intruder may know all about H and have access to the table, but he can penetrate the system only if he can invert H to determine an input that produces a given output.This paper discusses issues surrounding selection of a suitable H. Two different plausible arguments are given that penetration would be exceedingly difficult, and it is then argued that more rigorous results are unlikely. Finally, some human engineering problems relating to the scheme are discussed.


Journal ArticleDOI
TL;DR: In this paper, the authors tested price, newspaper advertising, display space, and display location quality at two levels for selected fruits and vegetables according to a fractional factorial research design.
Abstract: Retail price, newspaper advertising, display space, and display location quality were tested at two levels for selected fruits and vegetables according to a fractional factorial research design in ...

Journal ArticleDOI
TL;DR: Aphasic and non-neurological patients grouped nouns on the basis of similarity of meaning as mentioned in this paper, and these word groupings served as input matrices for hierarchical clustering and multidimensional scaling analyses.

Journal ArticleDOI
TL;DR: In this paper, the existence and nature of these singularities, and the possible fate of matter which crosses the Cauchy horizon in such a universe are examined, illustrated by simple models based on two-dimensional Minkowski space-time; the possibility of other types of singularity occuring is considered.
Abstract: In many cases the spatially homogeneous cosmological models of General Relativity begin or end at a “big bang” where the density and temperature of the matter in the universe diverge. However in certain cases the spatially homogeneous development of these universes terminates at a singularity where all physical quantities are well—behaved (a “whimper”) and an associated Cauchy horizon. We examine the existence and nature of these singularities, and the possible fate of matter which crosses the Cauchy horizon in such a universe. The nature of both kinds of singularity is illustrated by simple models based on two-dimensional Minkowski space-time; and the possibility of other types of singularity occuring is considered.

L. Morino1
01 Dec 1974
TL;DR: In this article, a general theory of potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented, and an integral representation for the potential is obtained for both supersonic and subsonic flow.
Abstract: The general theory of potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented. By using the Green function method, an integral representation for the potential is obtained for both supersonic and subsonic flow. Under small perturbation assumption, the potential at any point, P, in the field depends only upon the values of the potential and its normal derivative on the surface, sigma, of the body. Hence, if the point P approaches the surface of the body, the representation reduces to an integro-differential equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface sigma. For the important practical case of small harmonic oscillation around a rest position, the equation reduces to a two-dimensional Fredholm integral equation of second-type. It is shown that this equation reduces properly to the lifting surface theories as well as other classical mathematical formulas. The question of uniqueness is examined and it is shown that, for thin wings, the operator becomes singular as the thickness approaches zero. This fact may yield numerical problems for very thin wings.

Journal ArticleDOI
TL;DR: Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, Dept. of Endodontics, 1973.

Journal ArticleDOI
TL;DR: Desmosomes, isolated from cow nose epidermis by a method utilizing citrate buffer pH 2.6 and density gradient centrifugation, have been analyzed and found to contain approximately 76% protein, 17% carbohydrate, and 10% lipid.
Abstract: Desmosomes, isolated from cow nose epidermis by a method utilizing citrate buffer pH 2.6 and density gradient centrifugation, have been analyzed and found to contain approximately 76% protein, 17% carbohydrate, and 10% lipid. Nonpolar amino acids predominate in desmosomal protein, representing 456 residues per 1,000. The sialic acid content is 5 nM/mg of protein. The lipid fraction is composed of approximately 40% cholesterol and 60% phospholipids. Desmosomes are completely solubilized by incubation with 2% sodium dodecyl sulphate and 1% s-mercaptoethanol. Gel electrophoresis of the denatured desmosomal proteins reveals 24 bands, with mobilities corresponding to a molecular weight range of 15,000–230,000 daltons. Seven of these are considered to be major bands, together constituting 81% of the desmosomal protein. Bands 1 and 2, of molecular weights 230,000 and 210,000 daltons, together comprise 28% by weight of the desmosome. It is suggested that these protein chains are located in the desmosomal plaque. Bands 3 and 4 are PAS-positive, constitute 23% of the desmosomal protein, and have apparent molecular weights of 140,000 and 120,000 daltons, respectively. At least part of this material must originate from the carbohydrate-containing layer which is demonstrated, by histochemistry, to be present in the desmosomal interspace. The possible nature and origin of the remaining major bands, of molecular weights 90,000, 75,000, and 60,000 daltons, are discussed.

Journal ArticleDOI
TL;DR: Electron microscopy with both thin sections of pellets and unfixed spread preparations reveals that after centrifugation, desmosomes are located mainly at the 55–60% sucrose interface.
Abstract: A method is reported for the isolation of desmosomes in a high yield and of a purity suitable for biochemical analysis. The procedure utilizes the selective solubilizing action of citric acid-sodium citrate (CASC) buffer, pH 2.6, on the non-cornified layers of cow nose epidermis, followed by discontinuous sucrose density gradient centrifugation. Electron microscopy with both thin sections of pellets and unfixed spread preparations reveals that after centrifugation, desmosomes are located mainly at the 55–60% sucrose interface. In the desmosome preparation thus obtained, the characteristic desmosome structure is well preserved, showing the midline, unit membranes, and dense plaques. Furthermore, removal of the epidermal filament bundles by the solubilizing action of CASC buffer has revealed a finely filamentous layer on the cytoplasmic surface of the plaques. The dimensions, location, and appearance of this layer correspond with those of the "connecting component" which has been previously suggested as being responsible for the attachment of epidermal filament bundles to the desmosome.

Journal ArticleDOI
TL;DR: This article found that Korsakoff patients are impaired on even these rudimentary encoding tasks, which led to the proposal that semantic encoding deficit might stem from an initial impairment in the speed at which physical and nominal properties of verbal information are analyzed.

Journal ArticleDOI
TL;DR: Eight of 70 patients with systemic lupus erythematosus followed for a median interval of 6 years and 8 months, developed malignancies, including a case of reticulum-cell sarcoma, multiple myeloma, Bowen's carcinoma of the skin and five carcinomas of the cervix.
Abstract: Eight of 70 patients with systemic lupus erythematosus (SLE) followed for a median interval of 6 years and 8 months, developed malignancies. These included a case of reticulum-cell sarcoma, multiple myeloma, Bowen's carcinoma of the skin and five carcinomas of the cervix. Six of the patients had been treated with corticosteroids, in 2 cases in association with azathioprine. An increased incidence of malignancy may be present in SLE and this possibility should be explored further.

Journal ArticleDOI
TL;DR: In this article, the authors derived exact master equations for two or more systems coupled to each other, perhaps strongly, by using a generalization of the usual projection operator technique to include time-dependent projection operators.
Abstract: In this paper we derive master equations for two or more systems coupled to each other, perhaps strongly, by using a generalization of the usual projection-operator technique to include time-dependent projection operators. The coupled systems may be either similar or dissimilar and classical or quantum mechanical. Whereas the customary approaches to coupled systems are best able to treat situations in which some of the systems are "baths" with a specified density operator or phase-space probability density, our approach allows us to treat situations where it is necessary or convenient to treat the coupled systems on an equal footing. In our scheme the "relevant" part of the full density operator is considered to be the uncorrelated part of the full density operator and is a symmetric functional of the reduced density operators of each of the coupled subsystems. The "irrelevant" part of the density operator is then the part describing correlations between the coupled systems. Our formalism is particularly useful where systems are coupled to one another predominantly in a self-consistent fashion. First, we develop exact master equations for two coupled systems, taking as our prototype the dynamical problem of quantum optics, where a spatially extended collection of two-level atoms interact with a multimode optical field. We then generalize our results to $N$ coupled systems, taking as our prototype the kinetics of a classical nonideal gas interacting through two-body forces, and derive exact master equations for the system. We then consider as examples several approximate theories resulting from our exact equations. In the case of the imperfect gas we investigate the low-density limit and show how Bogoliubov's form of the Boltzmann equation emerges from our formalism, as well as corrections due to Klimontovich. We consider as special cases of our exact quantum-optical equations the equations in the first Born approximation, with and without memory, and show how several existing quantum-optical master equations are contained in our general results. As a second example in quantum optics, we consider the case where the predominant behavior of the system is described by the self-consistent-field or coupled Bloch and Maxwell equations and derive a first-order perturbation description for deviations from self-consistent-field behavior.

Journal ArticleDOI
TL;DR: The phase behavior of bovine brain sphingomyelin in water has been determined by polarizing light microscopy, differential scanning calorimetry, and X-ray diffraction.

Journal ArticleDOI
25 Oct 1974-Nature
TL;DR: The binding of cis-Pt(NH3)2Cl2 to DNA results in large increases in buoyant density which are proportional to the G–C content of the DNA and to the molar ratio of platinum to DNA-P.
Abstract: ONE of the more effective cis-platinum antitumour compounds currently being tested in cancer chemotherapy is cis-Pt(NH3)2Cl2 (ref. 1). Evidence suggests that DNA is the effective site of action of the platinum drug2,3. This study was initiated to determine the effective binding site on DNA. Roberts and Pascoe have noted the similarity of action between cis-Pt (NH3)2Cl2 and the classical antitumour bifunctional alkylating agents which crosslink DNA (ref. 2). Low concentrations of several cis-platinum compounds suppress DNA synthesis in vitro while affecting protein and RNA synthesis to a much lesser extent3. The studies by Horacek and Drobnik employing ultraviolet absorption spectroscopy indicate that the platinum moiety binds to the bases of DNA rather than to the phosphate backbone4. Spectroscopic studies suggest that cis-Pt(NH3)2Cl2 preferentially binds to guanine–cytosine (G–C)-rich DNA5,6. An increase in the buoyant density of T7 DNA and calf thymus DNA has been reported when one of several platinum compounds is present in solution5,7. Here we report that the binding of cis-Pt(NH3)2Cl2 to DNA results in large increases in buoyant density which are proportional to the G–C content of the DNA and to the molar ratio of platinum to DNA-P.