Showing papers by "University of Connecticut published in 1971"

Diabatic States of Molecules- Quasistationary Electronic States

Abstract: Publisher Summary This chapter focuses on diabatic states of molecules. Quasi-stationary state representation is proposed as a general definition of the diubutic or collisional electronic states of molecules, diatomic, and polyatomic. The identification of the single configuration diabatic states that seem to be followed by atoms colliding in nature appears to be an important step in understanding atomic collisions. Because an electron taken far away from the residual core sees the screened charge of a neutral system rather than an attractive Coulomb field, there are no Rydberg states for negative systems.

Olfactory bulb removal eliminates maternal behavior in the mouse.

Abstract: Olfactory bulb removal eliminated maternal behavior in lactating and in virgin mice. The results are in contrast to the generally accepted concept of multisensory control of mammalian maternal behavior.

Particle Formation in Polymer Colloids, III: Prediction of the Number of Particles by a Homogeneous Nucleation Theory

Abstract: The formation of particles in polymer colloids ordinarily is accomplished by the free radical polymerization of an organic monomer in a liquid which is a non-solvent (diluent) for the polymer. A surface active material, such as a soap or other amphipathic molecule, is usually added to stabilize the colloidal particles as they are formed. The particle size distribution varies from very narrow to extremely broad depending primarily upon the solubility of the monomer in the diluent, the stabilizer concentration and the ionic strength.

Interferon action: inhibition of vesicular stomatitis virus RNA synthesis induced by virion-bound polymerase.

Abstract: The particle-bound RNA polymerase activity of vesicular stomatitis virus (VSV) can be demonstrated in vivo. Linear synthesis of viral RNA persists for 5 to 6 hours at 34°C in infected monolayers of chick embryo cells treated with cycloheximide and actinomycin D to block synthesis of protein and cell-specific RNA. At least 55 percent of the RNA made under these conditions is complementary to virion RNA. RNA synthesis mediated by VSV polymerase activity is inhibited in cells first treated with chick-derived interferon or polyriboinosinate• polyribocytidylate, but not by mouse interferon. The RNA product of VSV polymerase activity is present throughout the cytoplasm, and its synthesis is inhibited by the interferon system, as judged by autoradiographs that show the physical distribution, in cells, of RNA produced by virion polymerase in the absence of translation—a demonstration of the transcription product of the viral genome.

African Swine Fever Virus

Abstract: African swine fever virus (ASFV) is a large, intracytoplasmically-replicating DNA arbovirus and the sole member of the family Asfarviridae. It is the etiologic agent of a highly lethal hemorrhagic disease of domestic swine and therefore extensively studied to elucidate the structures, genes, and mechanisms affecting viral replication in the host, virus-host interactions, and viral virulence. Increasingly apparent is the complexity with which ASFV replicates and interacts with the host cell during infection. ASFV encodes novel genes involved in host immune response modulation, viral virulence for domestic swine, and in the ability of ASFV to replicate and spread in its tick vector. The unique nature of ASFV has contributed to a broader understanding of DNA virus/host interactions.

Ear differences in the recall of fricatives and vowels.

Abstract: Two experiments on the free recall of dichotically presented synthetic speech sounds are reported. The first shows that the right ear advantage for initial fricative consonants is not simply a function of the recognition response class, but that it is also a function of the particular acoustic cues used to achieve that response. This is true both for the whole response, and for the constituent phonetic features. The second experiment shows that when both the response class and the particular stimuli presented on certain trials are held constant, the right ear advantage for the constant stimuli can be influenced by the range of other stimuli occurring in the experiment. Vowels show a right ear advantage when, within the experiment, there is uncertainty as to vocal tract size, but they show no ear advantage when all the vowels in the experiment are from the same vocal tract. These results are interpreted as demonstrating that there are differences between the ears, and probably between the hemispheres, at s...

Basic research in speech and lateralization of language: Some implications for reading disability

Abstract: Basic research in speech and the lateralization of language is shown to illuminate the problems of reading and some of its disabilities. First, it is pointed out how speech, or language for the ear, differs markedly from reading, or language for the eye. Though the sounds of speech are a very complex code and the optical shapes of written language are a simple cipher or alphabet on the phonemes, we all perceive speech easily but read only with difficulty. Perceiving speech is easy because, as members of the human race, we all have access to a special physiological apparatus that decodes the complex speech signal and recovers the segmentation of the linguistic message. Reading is hard because the phonemic segmentation, which is automatic and intuitive in the case of speech, must be made fully conscious and explicit. The syllabic method supplemented by phonics (used with certain reservations) is suggested for remediation of segmentation problems. Second, it is posited that since the sounds of speech are processed differently from non-speech sounds, the two should not be diagnosed and remediated interchangeably. Third, it is shown that the relationships among cerebral lateralization for language, handedness and poor reading can now be studied more meaningfully because of the recent development of new techniques. A truism often heard in the opening lecture of graduate classes in education is that we have few answers to the problems that beset us, only questions. In the field of reading, the difficulty may be owing at least in part to our impatient attempts to find immediate solutions for the teacher and the student in the classroom, and our consequent neglect of basic research. I should like to suggest today how knowledge of basic research in related disciplines may lead to clues for improving beginning reading instruction and the lot of the disabled reader—if only by affording us a deeper understanding of the reading process.

Special Adaptive Problems Associated with Unisexual Fishes

Abstract: SYNOPSIS. Two genera of fishes, Poecilia and Poeciliopsis, both in the family Poeciliidae, have established unisexual populations. One “species,” Poecilia formosa , is a diploid form that relies upon sperm from Poecilia latipinna or P. mexicana to initiate parthenogenetic development (gynogenesis). Triploid individuals of P. formosa have also been discovered but the mode of reproduction and the significance of such fish to natural populations have yet to be established. In the genus Poeciliopsis three gynogenetic triploids are known. Each is superimposed on a different bisexual host: Poeciliopsis lucida, P. monacha or P. viriosa. Five diploid hybridogeneticforms also have been identified. These are fertilized by either P. lucida, P. latidens, or P. occidentalis . In hybridogenetic forms, sperm actually feitilizes the egg. A hybrid with maternal and paternal characters is produced, but only maternal genes are transmitted through the egg to the next generation. Because of their sperm dependency, all unisexual fishes must reside with at least one of the parental species. They areforced to compete with them for sperm, space, and other limited resources. The ability to produce two females for every one that bisexuals produce suggests that the unisexuals have the potential to win this competition; but in so doing, they would lose their sexual support and eliminate themselves. A density-dependent mate selection system plays a role in establishing a workable balance between the competing elements. Unisexual forms of both Poecilia and Poeciliopsis are of hybrid origin. For most of them, the parental precursors and the proportion of genetic material that each contributed to the unisexual is known. The various genomes that make up the unisexuals are adapted to a variety of habitats. Once these genomes are combined in a unisexual hybrid, potential for adaptation to multiple niches exists; this coupled with heterosis contributes greatly to the success of gynogenetic and hybridogenetic fishes.

Light and electron microscopy of the leucocytes of Crassostrea virginica (Mollusca: Pelecypoda).

Abstract: The fine structure of oyster leucocytes resembles to a great extent, that of typical eucaryotic cells. Organelles which have been described for the first time in this report are light granules, dense granules, protocentriole and X structure. Light microscopy reveals two morphological types of oyster leucocytes: agranular and granular. Based upon nuclear morphology and cytoplasmic compositions revealed in electron microscopy, at least three types of agranular and one type of granular cells are recognized.

Evaluation of the effectiveness of comprehensive and continuous pediatric care.

Abstract: Two controlled studies were undertaken to evaluate the effectiveness of comprehensive and continuous pediatric care. In the first study, 220 infants of primiparous adolescents were randomly allocated to either a comprehensive care (CC) or traditional care (TC) group. CC infants received all medical care, preventive and therapeutic, in a hospital-based program staffed by a pediatrician, public health nurse, and social worker. Mothers of TC infants were left to obtain care from emergency rooms, well-baby and outpatient clinics. One year after delivery, each mother was interviewed and her infant9s medical records abstracted. No differences were found between CC and TC infants in completeness of immunization, utilization of medical resources, morbidity, or mortality. In a second study, it was hypothesized that patient compliance with physicians9 recommendations would be favorably influenced by continuous care. Seventy-seven children on daily oral penicillin prophylaxis for history of rheumatic fever (RF) were studied. For one year, compliance was determined by periodic urine tests for penicillin. Patients were then stratified for age, sex, and compliance and randomly allocated to continuous care (CC) or traditional care (TC) groups. CC patients received all medical care, even for problems unrelated to RF, from the same two physicians for 15 months. TC patients continued to receive specialty clinic care, were seen at the RF clinic by different physicians and referred elsewhere for all problems unrelated to RF. Urine specimens were tested periodically for penicillin. After 15 months, no differences were observed between CC and TC groups in proportion of noncompliers or in internal shifts in compliance which had occurred during the study. Thus, neither of these studies was able to demonstrate that comprehensive and continuous care was more effective than conventional ambulatory care for children.

Waiting for the stimulus suffix: Decay, delay, rhythm, and readout in immediate memory

Abstract: The degree to which a redundant suffix impairs performance on digit lists depends on the delay between the last memory item and the suffix. A set of three experiments is offered, establishing the inadequacy of hypotheses based on simple decay of prelinguistic information, passage of time before recall, and rhythmic periodicities in attention. The delayed suffix effect is consistent with a fourth hypothesis whose emphasis is on access to precategorical auditory information through a “readout” process rather than on the sheer availability of such information.

The Mechanochemistry of High Polymers

Abstract: Several different schools of workers have dominated research in the field of polymer mechanochemistry. These include the Russian school with Baramboim, Berlin, Butyagin; Watson, Ceresa and others of the Natural Rubber Producers' Research Association; and a host of other European workers. Also active are the Japanese and Rumanian groups. In the U. S. the activity has centered at the National Bureau of Standards and in a number of labs including our own. The tables for the review summarize mechanochemical studies on individual polymers, multicomponent polymer systems, and on polymer solutions. For a field so important, it is surprising so few summaries have been prepared. An early review (1960), emphasizing the mechanical degradation of rubber, was prepared by Watson. The classic book on Mechanochemistry of Polymers by Baraboim was published in English in 1964. In the same year Watson also published an excellent book chapter on mechanochemical reactions. Other general volumes and reviews on polymer...

Public Attitudes Toward the Trustworthiness, Competence, and Altruism of Twenty Selected Occupations.

Abstract: Ratings on 4-point scales of truthfulness, competence, and altruism of 20 selected occupations were obtained from 4 samples of subjects. The subjects included 200 students from the University of Connecticut, 96 students from the University of Maryland, 50 secretaries from a small town in Connecticut, and 50 teachers from the public schools of the same town. In spite of differences in sex, age, occupation, education, and locale, all the samples and subsamples were remarkably similar in their ratings of the 20 occupations. A strong tendency appears for professionals to be rated high and for people who may be regarded as powerful in our society to be rated poorly on all 3 variables. Several interesting differences in ratings on the 3 variables within professions were obtained.

Abnormal Concentrations of Nickel in Serum in Cases of Myocardial Infarction, Stroke, Burns, Hepatic Cirrhosis, and Uremia

Abstract: Nickel concentrations were measured by atomic absorption spectrometry in sera. The mean concentration of nickel in sera of 47 healthy adults was 2.6 SD ± 0.8) µg/liter. Abnormally high mean concentrations (µg/liter) of serum nickel were found in patients with: ( a ) acute myocardial infarction (13-36 h after onset), mean = 5.2 ± 2.8, N = 33, P 25% body surface, 37-72 h after injury), mean = 7.2, N = 3, range = 4.1-10.9. Diminished mean concentrations of serum nickel were found in patients with: ( a ) hepatic cirrhosis, mean = 1.6 ± 0.8, N = 18, P <0.005; and ( b ) chronic uremia, mean = 1.7 ± 0.7, N = 12, P = <0.005. Normal mean concentrations of serum nickel were found in patients with: ( a ) acute myocardial ischemia without infarction (13-36 h after onset), mean = 3.3 ± 1.6, N = 22; ( b ) acute trauma with fractured bones (13-36 h after injury), mean = 2.7 ± 0.9, N = 19; ( c ) acute delirium tremens (13-36 h after admission), mean = 2.3 ± 0.9, N = 25; and ( d ) muscular dystrophy, mean = 2.3 ± 1.4, N = 10. In sera collected from 12 mothers immediately after normal delivery, the mean concentration of nickel was 3.0 ± 1.2 µg/liter, the same values as for sera from the umbilical cords of their 12 full-term infants.

Studies on the genetic control of tryptophan pyrrolase in Drosophila Melanogaster

Abstract: A reexamination of the role of the vermilion cistron (v: 1–33.0) in the control of tryptophan pyrrolase in Drosophila melanogaster uncovered several, previously unknown features about this enzyme: 1. Crude extracts of Drosophila possess one or more inhibitors which may be removed by Norit treatment during homogenization. 2. Contrary to previous assertion, crude wild type extracts are stimulated by an exogenous source of hematin, and upon purification, become heavily dependent upon added methemoglobin. 3. The wild type enzyme exhibits a lag period in time course of product accumulation which is eliminated by preincubation with methemoglobin and α-methyltryptophan. 4. The molecular weight of the wild type enzyme is estimated at approximately 150000 Daltons. 5. A linear increase of tryptophan pyrrolase activity as a function of dosage of v+ alleles supports the contention that the vermilion cistron is the structural gene for this enzyme. 6. A sex difference in response to gene dosage (dosage compensation) is seen.

Rotationally Induced Transitions in Atomic Collisions

Abstract: Excitation effects due to rotational motion of the internuclear line during an atomic collision are considered in the two-state approximation. These effects are governed by a pair of first-order differential equations which couple adiabatic levels of different angular momentum (e.g., $\ensuremath{\sigma}$ to $\ensuremath{\pi}$ transitions), which actually do cross. The equations are cast in such a form that the solution for rotational excitation may be expressed in terms of the well-known Landau-Zener solution. It is found, however, that application of these results to a real collision suffers from defects which are worse for the case of rotational excitation than for ordinary Landau-Zenner transitions. The coupled differential equations are then solved numerically to document the shortcomings of the Landau-Zener approach to a real collision and to present cross-section results which are free from these defects.