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Showing papers by "Stony Brook University published in 1988"


Journal ArticleDOI
TL;DR: In this relatively brief study, the apparently increased comparative risk of agranulocytosis requires that the use of clozapine be limited to selected treatment-resistant patients.
Abstract: • The treatment of schizophrenic patients who fail to respond to adequate trials of neuroleptics is a major challenge. Clozapine, an atypical antipsychotic drug, has long been of scientific interest, but its clinical development has been delayed because of an associated risk of agranulocytosis. This report describes a multicenter clinical trial to assess clozapine's efficacy in the treatment of patients who are refractory to neuroleptics.DSM-IIIschizophrenics who had failed to respond to at least three different neuroleptics underwent a prospective, single-blind trial of haloperidol (mean dosage, 61 ±14 mg/d) for six weeks. Patients whose condition remained unimproved were then randomly assigned, in a double-blind manner, to clozapine (up to 900 mg/d) or chlorpromazine (up to 1800 mg/d) for six weeks. Two hundred sixty-eight patients were entered in the doubleblind comparison. When a priori criteria were used, 30% of the clozapine-treated patients were categorized as responders compared with 4% of chlorpromazine-treated patients. Clozapine produced significantly greater improvement on the Brief Psychiatric Rating Scale, Clinical Global Impression Scale, and Nurses' Observation Scale for Inpatient Evaluation; this improvement included "negative" as well as positive symptom areas. Although no cases of agranulocytosis occurred during this relatively brief study, in our view, the apparently increased comparative risk requires that the use of clozapine be limited to selected treatment-resistant patients.

3,842 citations


Journal ArticleDOI
TL;DR: In this article, the authors review the theoretical models that have been developed to describe the physics of polyacetylene and related conducting polymers and summarize the relevant experimental results obtained for these materials.
Abstract: Self-localized nonlinear excitations (solitons, polarons, and bipolarons) are fundamental and inherent features of quasi-one-dimensional conducting polymers. Their signatures are evident in many aspects of the physical and chemical properties of this growing class of novel materials. As a result, these polymers represent an opportunity for exploring the novel phenomena associated with topological solitons and their linear confinement which results from weakly lifting the ground-state degeneracy. The authors review the theoretical models that have been developed to describe the physics of polyacetylene and related conducting polymers and summarize the relevant experimental results obtained for these materials. An attempt is made to assess the validity of the soliton model of polyacetylene and its generalization to related systems in which the ground-state degeneracy has been lifted.

2,907 citations


Journal ArticleDOI
20 May 1988-Cell
TL;DR: It is concluded that c-K-ras somatic mutational activation is a critical event in the oncogenesis of most, if not all, human cancers of the exocrine pancreas.

2,146 citations



Journal ArticleDOI
TL;DR: In this article, the authors show that a previously derived shift in the dilaton field, which augments the classical effects of duality transformation on the geometry of a nonlinear sigma-model if conformal invariance is to be preserved at the one-loop level, can be extended without change to the case of sigma models with Wess-Zumino-Witten term (torsion) before and after duality.

1,058 citations



Journal ArticleDOI
TL;DR: This paper discusses measurement of the local thickness t of a transmission microscope specimen from the log-ratio formula t = lambda ln (It/I0) where It and I0 are the total and zero-loss areas under the electron-energy loss spectrum.
Abstract: We discuss measurement of the local thickness t of a transmission microscope specimen from the log-ratio formula t = lambda ln (It/I0) where It and I0 are the total and zero-loss areas under the electron-energy loss spectrum. We have measured the total inelastic mean free path lambda in 11 materials of varying atomic number Z and have parameterized the results in the form lambda = 106F (E0/Em)/ln (2 beta E0/Em) where F = (1 + E0/1,022)/(1 + E0/511)2, the incident energy E0 is in keV, the spectrum collection semiangle beta is in mrad, and Em = 7.6Z0.36. This formulation should allow absolute thickness to be determined to an accuracy of +/- 20% in most inorganic specimens.

757 citations


Journal ArticleDOI
TL;DR: On discute du systeme de liaisons de valence resonnantes a courte distance realise par un gaz de dimeres a cœur dur quantique de densite arbitraire sur un reseau carre a deux dimensions.
Abstract: We discuss the short-range resonating-valence-bond system as realized by a quantum hard-core dimer gas of arbitrary density on a two-dimensional square lattice. When the dimers completely cover the lattice, we argue that there is a first-order transition from a dimer crystal to an insulating quantum liquid state which possesses low-energy, neutral, spinless excitations which we call "resonons." For less than close-packed densities, the ground state is a superfluid. In addition to the usual Goldstone mode, there are low-energy, spinless zone-boundary excitations.

755 citations


Journal ArticleDOI
TL;DR: In this article, a framework consisting of three parts: a procedural analysis, a causal analysis, and a theoretical analysis is proposed to integrate research from all three research areas, including social learning theory, Herrnstein's matching law, and optimal foraging theory.
Abstract: The tendency to choose a larger, more delayed reinforcer over a smaller, less delayed one has frequently been termed “selfcontrol.” Three very different research traditions – two models emphasizing the control of local contingencies of reinforcement (Mischel's social learning theory and Herrnstein's matching law) and molar maximization models (specifically optimal foraging theory) – have all investigated behavior within the self-control paradigm. A framework is proposed to integrate research from all three research areas. This framework consists of three parts: a procedural analysis, a causal analysis, and a theoretical analysis. The procedural analysis provides a common procedural terminology for all three areas. The causal analysis establishes that, in all three research traditions, self-control varies directly with the current physical values of the reinforcers; that is, choices increase with reinforcer amount and decrease with reinforcer delay. But self-control also varies according to past events to which a subject has been exposed, and according to current factors other than the reinforcers. Each of the three models has therefore incorporated these indirect effects on self-control by postulating unobservable mechanisms. In all three cases, these mechanisms represent a subject's behavior as a function of a perceived environment. The theoretical analysis demonstrates that evolutionary theory can encompass the research from all three areas by considering differences in the adaptiveness of self-control in different situations. This integration provides a better and more predictive description of self-control.

736 citations


Journal ArticleDOI
TL;DR: It is concluded that the protease that cleaves T7 RNA polymerase is OmpT (formerly termed protein a), a known outer membrane endoprotease, and that the null phenotype results from deletion of the OMPT structural gene.
Abstract: Bacteriophage T7 RNA polymerase is stable in Escherichia coli but very susceptible to cleavage by at least one endoprotease after cell lysis. The major source of this endoprotease activity was found to be localized to the outer membrane of the cell. A rapid whole-cell assay was developed to screen different strains for the presence of this proteolytic activity. Using this assay, we identified some common laboratory strains that totally lack the protease. Genetic and Southern analyses of these null strains allowed us to conclude that the protease that cleaves T7 RNA polymerase is OmpT (formerly termed protein a), a known outer membrane endoprotease, and that the null phenotype results from deletion of the OmpT structural gene. A recombinant plasmid carrying the ompT gene enables these deletion strains to synthesize OmpT and converts them to a protease-positive phenotype. The plasmid led to overproduction of OmpT protein and protease activity in the E. coli K-12 and B strains we used, but only weak expression in the E. coli C strain, C1757. This strain-dependent difference in ompT expression was investigated with respect to the known influence of envZ on OmpT synthesis. A small deletion in the ompT region of the plasmid greatly diminishes the amount of OmpT protein and plasmid-encoded protease present in outer membranes. Use of ompT deletion strains for production of T7 RNA polymerase from the cloned gene has made purification of intact T7 RNA polymerase routine. Such strains may be useful for purification of other proteins expressed in E. coli.

683 citations


Journal ArticleDOI
11 Jul 1988
TL;DR: This "Doppler cooling limit" results from the minimization of the detuning-dependent temperature at low laser power1.
Abstract: The generally accepted theory of laser cooling of free atoms predicts that the lowest achievable temperature is given by kaT = hγ/2, where kB is Boltzmann's constant arid γ is the natural linewidth of the transition for laser cooling. This "Doppler cooling limit" results from the minimization of the detuning-dependent temperature at low laser power1:

Journal ArticleDOI
TL;DR: The organization of retinohypothalamic tract (RHT) projections in the rat and hamster was studied using anterograde transport of cholera toxin conjugated to HRP (CT-HRP).

Journal ArticleDOI
TL;DR: Results showed children's behavioral and developmental status, as well as mothers' internal models, to be associated with dyadic behavior, even with the effects of mothers' behavior removed.
Abstract: Interactional behavior of mothers and preschool children was studied in light of mothers' internal models of relationships and select child characteristics. Children with behavior problems who were developmentally intact (n = 20) and developmentally delayed (n = 20), and a matched nonclinic group (n = 24), were studied in a problem-solving session. Mothers' help and support, and children's approach to tasks, relationship to mother, and overall experience were scored. Mothers' internal models of relationships, based on descriptions of childhood relationships, were characterized as detached, preoccupied, or secure (attachment classifications). Results showed children's behavioral and developmental status, as well as mothers' internal models, to be associated with dyadic behavior. Children's behavior corresponded to mothers' internal models and to behavioral and developmental status even with the effects of mothers' behavior removed. Discriminant analysis correctly classified 93% of the sample into clinic and nonclinic groups and into the 3 attachment classifications.

Journal Article
TL;DR: Developpement d'un modele pour la coexistence ilmenite ss -magnetite ss, fonde sur des donnees experimentales nouvelles et existant deja pour les oxydes Fe-Ti and utilisant une programmation lineaire qui est egalement coherente de facon interne avec les donnes disponibles sur l'echange Fe-Mg dans olivine ss -ilmenitess and olivINE ss -grenat ss as mentioned in this paper.
Abstract: Developpement d'un modele pour la coexistence ilmenite ss -magnetite ss , fonde sur des donnees experimentales nouvelles et existant deja pour les oxydes Fe-Ti et utilisant une programmation lineaire qui est egalement coherente de facon interne avec les donnees disponibles sur l'echange Fe-Mg dans olivine ss -ilmenite ss et olivine ss -magnetite ss et sur l'echange Fe-Mn dans ilmenite ss -grenat ss

Journal ArticleDOI
TL;DR: In this paper, the star-triangle relations for a nearest-neighbour two-spin interaction model are given in terms of two rapidities associated with two lines, which cross through each edge.

Journal ArticleDOI
TL;DR: In this article, three knife cut procedures were used and one of these succeeded in separating the SCN from the optic chiasm in 8 animals with limited damage to the chiasm and SCN.

Journal ArticleDOI
TL;DR: Using simultaneous whole cell voltage clamp and video analysis, it is demonstrated that the mechanical response of OHCs is not altered by agents which alter membrane currents under voltage clamp, thus the underlying mechanism of O HC movements appears to be dependent upon membrane potential, rather than transmembrane currents.

Journal ArticleDOI
TL;DR: The findings show that dry mouth and several other symptoms are common in an outpatient population and they are a valid indicator of salivary gland hypofunction.

Journal ArticleDOI
TL;DR: In this article, static and dynamic light-scattering studies on the temperature-induced micellization behavior in aqueous solutions of poly (oxyethylene-oxypropylene-oxyethylenes) block copolymer, poloxamer 188, are presented.

Journal ArticleDOI
TL;DR: Gut clearance rate constant (K) of T. longicornis was positively related to temperature (T) and the relationship was best described by the equation K = 0.0119 + 0.001904T, and it is suggested that K may be estimated by knowledge of ambient temperature if food conditions are not limiting.

Journal ArticleDOI
TL;DR: The relationship between the maximum neutron- star mass and observable parameters of the equation of state is explored and it is concluded that the compression modulus cannot, by itself, be severely limited by observed neutron-star masses.
Abstract: The relationship between the maximum neutron-star mass and observable parameters of the equation of state is explored. In particular, the roles of the nuclear incompressibility and the symmetry energy are considered. It is concluded that, for realistic symmetry energies, the compression modulus cannot, by itself, be severely limited by observed neutron-star masses. Several directions for further study are suggested.


Journal ArticleDOI
TL;DR: Central nervous system dysfunction was documented in 61 of 68 infants and children with symptomatic human immunodeficiency virus infection and postmortem findings included variable degrees of inflammatory response, multinucleated cells, calcific vasculopathy, and pyramidal tract degeneration.
Abstract: • Central nervous system (CNS) dysfunction was documented in 61 of 68 infants and children with symptomatic human immunodeficiency virus infection. The most frequent manifestations included acquired microcephaly, cognitive deficits, and bilateral pyramidal tract signs. Lymphoma of the CNS, cerebrovascular accidents, and CNS infection caused by conventional pathogens were documented in only ten children (15%). Neurologic deterioration in 11 children was subacute but steadily progressive; in 31 the course was more indolent and began with a plateau. Of these 31 children, 13 had further neurologic deterioration and the conditions of three improved. Seventeen children had a static course with cognitive deficits (seven children) or cognitive plus neurologic impairment (ten children). Neuroradiologic studies in the children with a subacute progressive or plateau course disclosed cerebral atrophy, white matter abnormalities, and calcification of the basal ganglia. Postmortem findings included variable degrees of inflammatory response, multinucleated cells, calcific vasculopathy, and pyramidal tract degeneration. Computed tomographic studies of the children with a static course were normal or showed mild atrophy, but poor brain growth was documented by serial head circumference measurements. ( AJDC 1988:142:29-35)

Journal ArticleDOI
TL;DR: Sera containing IgG anti-IgE antibodies gave a strongly positive transfer test at 5 h but not 48 h, suggesting a pathogenic role for the IgG, and several positive sera were capable of inducing histamine release from normal peripheral basophils and caused a wheal-flare response upon intradermal injection.

Journal ArticleDOI
TL;DR: This article presents the results of a clinical study in which an experimental preventive fluoride program was routinely used in the orthodontic offices of the authors, designed to provide answers to the following questions.

Journal ArticleDOI
TL;DR: For instance, this article found that students and faculty were generally similar, though not identical, in their views, as indicated by an average correlation of +.71 between them in their valuation of various aspects of teaching.
Abstract: Thirty-one studies were located in each of which students and faculty specified the instructional characteristics they considered particularly important to good teaching and effective instruction. Students and faculty were generally similar, though not identical, in their views, as indicated by an average correlation of +.71 between them in their valuation of various aspects of teaching. In those studies with relevant data, the differences that did exist between the two groups showed a pattern of students placing more importance than faculty on teachers being interesting, having good elocutionary skills, and being available and helpful. Students also emphasized the outcomes of instruction more than faculty did. Faculty placed more importance than did students on teachers being intellectually challenging, motivating students and setting high standards for them, and encouraging self-initiated learning. The results of the present analysis were compared with those of an earlier analysis of the importance of various specific aspects of instruction in terms of their correlations with students' overall evaluations of teachers in actual rating situations.

Journal ArticleDOI
TL;DR: It is concluded that the presence of chronic Lyme disease cannot be excluded by the absence of antibodies against B. burgdorferi and that a specific T-cell blastogenic response to the spirochete is evidence of infection in seronegative patients with clinical indications of Chronic Lyme disease.
Abstract: The diagnosis of Lyme disease often depends on the measurement of serum antibodies to Borrelia burgdorferi, the spirochete that causes this disorder. Although prompt treatment with antibiotics may abrogate the antibody response to the infection, symptoms persist in some patients. We studied 17 patients who had presented with acute Lyme disease and received prompt treatment with oral antibiotics, but in whom chronic Lyme disease subsequently developed. Although these patients had clinically active disease, none had diagnostic levels of antibodies to B. burgdorferi on either a standard enzyme-linked immunosorbent assay or immunofluorescence assay. On Western blot analysis, the level of immunoglobulin reactivity against B. burgdorferi in serum from these patients was no greater than that in serum from normal controls. The patients had a vigorous T-cell proliferative response to whole B. burgdorferi, with a mean (±SEM) stimulation index of 17.8±3.3, similar to that (15.8±3.2) in 18 patients with chro...

Patent
27 Apr 1988
TL;DR: An endoscopic biopsy forceps device incorporating a novel and unique camming arrangement for selectively opening and closing the biopsy cutting jaws of the forceps was presented in this paper which will render the entire device of a simpler construction and reliable in operation, while concurrently making it considerably less expensive to produce.
Abstract: An endoscopic biopsy forceps device incorporating a novel and unique camming arrangement for selectively opening and closing the biopsy cutting jaws of the biopsy forceps which will render the entire device of a simpler construction and reliable in operation, while concurrently making it considerably less expensive to produce.

Journal ArticleDOI
TL;DR: New constructions of hyperkähler metrics along with the three new classes ofN=4 supermultiplets that they derive from are presented and a detailed description of the multiplets in N=2 and N=4 superspace is given.
Abstract: We present new constructions of hyperkahler metrics along with the three new classes ofN=4 supermultiplets that they derive from. Further, we provide a general setting for understanding the constructions and give a detailed description of the multiplets inN=2 andN=4 superspace.

Journal ArticleDOI
TL;DR: In this article, the authors examined the bonding properties of small boron cluster cations (BZTl3+) by measurement of appearance potentials and fragmentation patterns for collision-induced dissociation (CID) with Xe.
Abstract: Bonding in small boron cluster cations (BZTl3+) is examined by measurement of appearance potentials and fragmentation patterns for collision-induced dissociation (CID) with Xe. Cluster stabilities are generally found to increase with increasing cluster size; however, there are large fluctuations from the overall trend. The lowest energy fragmentation channel for all size cluster ions is loss of a single atom. Clusters smaller than six atoms preferentially lose B', while for the larger clusters the charge remains on the BW1+ fragment. The results are used to estimate cluster ionization potentials and geometries. Comparison of measured stabilities with "magic" numbers in the cluster ion size distribution and with total CID cross sections shows that neither is a reliable indicator of stability. We also report on ab initio calculations for both neutral and ionic BI4. The results include cluster geometries, ionization potentials, charge distributions, dissociation energies, and bonding character. The results for IPS, geometries, and De)s are compared with experiment.