Showing papers by "Michigan State University published in 1975"

Powdered chitin agar as a selective medium for enumeration of actinomycetes in water and soil.

Abstract: Agar media made with 0.4% colloidal chitin plus mineral salts and adjusted to pH 8.0 was superior to four other commonly used media for the isolation and enumeration of actinomycetes from water samples. More actinomycetes developed on chitin agar, and the development of bacteria and fungi was suppressed. Frozen and vacuum-dried chitin from aqueous colloidal suspensions was finely divided and gave results comparable to those obtained with media prepared from colloidal suspensions. Images

Analysis of Relational Communication in Dyads: New Measurement Procedures

Abstract: Relational communication refers to the control or dominance aspects of message exchange in dyads, as distinct from an emphasis on the report or referential aspects of communication. In relational communication analysis, the focus is on messages as transactions, and the major theoretic concepts which emerge in this analysis are symmetry, transitory, and complementarity of control. This paper contains a brief review and critique of existing interaction analysis techniques, followed by a detailed discussion of new measurement procedures that capture both the control and processual (time-varying) nature of dyadic interaction. The first step in these procedures yields a code (by speaker) based on the grammatical format of each sequential utterance. The second step yields a translation of each message format and response made into a control code, based on the relationship between the message and its immediate predecessor. These codes are next translated into transactional codes, which can then be analyzed in terms of the three major theoretic concepts. These measurement procedures require minimal subjective judgment, particularly at the initial coding level. The paper concludes with a discussion of the ways we are attempting to operationalize major “themes” or patterns of control in lengthy, ongoing dyadic exchanges.

Predictions of fate from rosette size in teasel (Dipsacus fullonum L.).

Abstract: In field populations of the biennial plant (Dipsacus fullonum L.) the probability that an individual will die, remain vegetative, or flower during a particular growing season is highly correlated with the size of its vegetative rosette at the end of the growing season of the preceding year. Further, a rosette forms a flowering stalk only after attaining a critical size. Correlations of various plant fates with rosette size are independent of rosette age; hence size provides better predictions of plant fate than age.

Women's Work and the Family in Nineteenth-Century Europe

Abstract: There is a great deal of confusion about the history of women's work outside the home and about the origin and meaning of women's traditional place within the home. Most interpretations of either of these questions depend on assumptions about the other. Usually, women at home in any time period are assumed to be non-productive, the antithesis of women at work. In addition, most general works on women and the family assume that the history of women's employment, like the history of women's legal and political rights, can be understood as a gradual evolution from a traditional place at home to a modern position in the world of work. Some historians cite changes in employment opportunities created by industrialization as the precursors of legal emancipation. Others stress political rights as the source of improved economic status. In both cases, legal-political and economic ‘emancipation’ usually are linked to changes in cultural values. Thus William Goode, whose World Revolution and Family Patterns makes temporal and geographic comparisons of family patterns, remarks on what he calls ‘the statistically unusual status of western women today, that is their high participation in work outside of the home’.

The need for an ethnomedical science.

Abstract: Ethnomedicine is an intellectual area which embraces theoretical concerns that are relevant to both the social and biological sciences. The relation which exists between disease, social behavior, and human adaptation constitutes the primary subject matter of ethnomedicine. This relation is examined in terms of man's unique capacities for symbolization and culture. Since ethnomedical generalizations explain how social groups deal with a generic disease, they can be used to examine contemporary problems which involve the organization and practice of medicine as well as problems that stem from relations of the medical system with other subsystems in the group. Recasting contemporary social problems in this way may help to clarify their roots and sources (13,28). In focusing on fundamental properties of disease in man, ethnomedicine can also help to clarify the effects and meanings of disease and thereby make its control more rational. A theory of disease, an ultimate aim of ethnomedical inquiry, will serve as an explanatory device with wide-ranging applications.

Microbial Inhibition by an Isolate of Pediococcus from Cucumber Brines

Abstract: We reported earlier that Pediococcus cerevisiae FBB-61 inhibited Lactobacillus plantarum FBB-67 in mixed species inoculation used for the fermentation of brined cucumbers. Herein, 16 isolates of the Pediococcus genus from various sources were tested for inhibitory activity against L. plantarum and other microorganisms by a seeded-agar screening technique. Only two of the 16 isolates gave consistent and distinctive zones of inhibition, and both were isolated from fermenting cucumber brines on separate occasions. These two isolates did not inhibit each other but did inhibit the other 14 Pediococcus isolates in addition to L. plantarum. They also inhibited several other gram-positive bacteria, but not four species each of gram-negative bacteria and yeasts tested. Inoculation of cucumber juice broth with P. cerevisiae FBB-61 and L. plantarum WSO resulted in a drastic reduction in the plate count of L. plantarum WSO during day 1, but counts increased rapidly thereafter. Consequently, acid production by L. plantarum WSO was delayed. Noninhibitory isolates of Pediococcus had no appreciable effect on growth and acid production by L. plantarum WSO.

Effects of acute stress on serum LH and prolactin in intact, castrate and dexamethasone-treated male rats.

Abstract: The effects of handling, ether vapor anesthesia and blood sampling on serum LH and prolactin were determined in intact, castrate and dexamethasone-treated male rats Cage removal and transport to an adjacent room increased LH and prolactin levels by 10 and 15 min after the initial animal disturbance Intact male rats subjected to repeated ether anesthesia and blood sampling showed a more rapid increase in serum LH and prolactin than the preceding rats, since serum LH and prolactin was increased by 4, 8 and 15 min after initial cage disturbance In a group of rats subjected to serial blood sampling over a longer time interval, both prolactin and LH levels remained higher than 90 min after initial animal handling At 90 minutes after a single blood sampling, blood prolactin concentration remained higher than in controls Serum LH levels returned to control levels 90 min after the stress of a single blood sampling Although serum prolactin was increased in the castrate group subjected to serial anesthesia and blood sampling, LH concentrations were reduced under the same conditions Injection of 5 and 50 mug of dexamethasone/100 g body wt for 8 days markedly reduced adrenocortical responsiveness to the stress of serial anesthesia and blood sampling at 1, 4, 8 and 15 min after initial rat disturbance The 50 mug dexamethasone treatment reduced the stress-stimulated increase in serum prolactin at all blood sampling intervals The dexamethasone-treated groups also showed smaller increases in serum LH at 8 and 15 min after first animal handling than the control rats These results indicate that serum LH and prolactin concentrations are consistently increased by acute stress in intact male rats, the duration of the stress stimulation of LH and prolactin is at least 90 min under the conditions of this study, serum LH levels of castrate male rats are decreased by acute stress and dexamethasone administration lowers stress stimulation of LH and prolactin release

Effects of castration and gonadal steroids on serum luteinizing hormone and prolactin in old and young rats

Abstract: Changes in serum LH and prolactin concentrations in response to bilateral gonadectomy and gonadal steroid replacement were measured in mature young (4-6 months) and old (23-30 months) female and male Long-Evans rats. On day 13 after gonadectomy, female rats were injected with oestradiol benzoate (OB) and male rats with testosterone propionate (TP) for a period of 12 days. They were then permitted a recovery period of 6 weeks. Serum prolactin and LH concentrations were measured by radioimmunassay in single blood samples taken at various intervals before and after gonadectomy and during and after steroid treatment. Serum LH levels were about the same in intact young old female rats, but after ovariectomy LH rose several fold higher in young than in old remale rats. In male rats, after orchidetomy the increase in serum LH was greater in young than in old rats. Oestradiol benzoate and TP injections into female and male young and old rats produced variable effects on LH release. Serum prolactin concentrations were approximately six times higher in old intact than in young intact female rats, and after ovariectomy showed a much greater percentage reduction in old than in young female rats. Administration OB produced a greater absolute increase in serum prolactin in old than in young female rats. Serum prolactin values were about the same in old and young male rats, and the effects of castration and TP administration on serum prolactin were not markedly different in the two age groups. These results indicate that old female and male rats are less capable of releasing LH than young rats of both sexes, but old females release more prolactin than young females.

Simultaneous Requirement of Carbon Dioxide and Abscisic Acid for Stomatal Closing in Xanthium strumarium L.

Abstract: Open stomata of detached leaves of Xanthium strumarium L. closed only when carbon dioxide and abscisic acid (ABA) were presented simultaneously. Three parameters of stomatal closing were determined after additions of ABA to the irrigation water of detached leaves, while the leaves were exposed to various CO2 concentrations ([CO2]s) in the air; a) the delay between addition of ABA and a reduction of stomatal conductance by 5%, b) the velocity of stomatal closing, and c) the new conductance. Changes in all three parameters showed that stomatal responses to ABA were enhanced by CO2; this effect followed saturation kinetics. Half saturation occurred at an estimated [CO2] in the stomatal pore of 200 μl l-1. With respect to ABA, stomata responded in normal air with half their maximal amplitude at [ABA]s between 10-6 and 10-5 M(+-)-ABA. The amounts of ABA taken up by the leaves during the delay increased with a power <1 (on the average, 0.67) of the [ABA] in the transpiration stream. The minimal amount of ABA found to produce a stomatal response was about 1 pmol of (+-)-ABA per cm2 leaf area, almost two orders of magnitude smaller than the original content of the leaves in ABA indicating that most of the endogenous ABA was in a compartment isolated from the guard cells. An interaction between stomatal responses to CO2 and ABA was also found in Gossypium hirsutum L. and Commelina communis L.; it was however much weaker than in X. strumarium. Based on earlier findings and on the results of this investigation it is suggested that stomata close if the cytoplasm of the guard cells contains much malate and H+. The acid content in turn is determined by the relative rates of production of malic acid (from endogenous as well as exogenous CO2) and its removal (by transport of the anion into the vacuole and exchange of the H+ for K+ with the environment of the guard cells). The simultaneous requirement of CO2 and ABA for stomatal closure leads to the inference that ABA inhibits the expulsion of H+ from guard cells.

Blockade of Testosterone-Induced Mounting Behavior in the Male Rat with Intracranial Application of the Aromatization Inhibitor, Androst-l,4,6-triene-3,17-dione

Abstract: Propylene glycol (glycol) solutions containing either testosterone (T) or estradiol (E2) were infused directly into the preoptic area (POA) of longterm castrated rats in order to reinstate male copulatory behavior. In addition, castrated males were administered T or E2 in the POA in combination with a steroid that has been shown to block the aromatization of testosterone to estradiol, androstl, 4,6-triene-3,17-dione (ATD). The facilitatory action of testosterone on mounting behavior was blocked when it was given in combination with ATD. Animals treated in the POA with glycol † T, glycol † E2, or ATD 4- E2 all showed significant increases in mounting behavior over preimplant levels. There was no significant rise in the number of intromissions or ejaculations in any of the treatment groups. These results support the hypothesis that, at least for mounting behavior, aromatization is necessary for the stimulation of male sexual behavior by testosterone. (Endocrinology 97: 1545, 1975)

Residential preferences and population distribution.

Abstract: Public opinion research has revealed decided preferences for living in rural areas and small towns, and proponents of population deconcentration have interpreted this as support for their policies. This study, based on a national sample, yielded similar results, but when we introduced the additional possibility of a preference for proximity to a larger city, then the rural areas preferred were found, for most respondents, to be those within the commuting range of a metropolitan central city. Although persons wishing to live near large cities were found to be looking for the same qualities of living sought by those who prefer a more remote location, these findings are not, in general, consistent with the argument that public preferences support strategies of population dispersal into nonmetropolitan areas. Instead they indicate that most of those who wish to live in a different location favor the peripheral metropolitan ring areas that have, in fact, been growing rapidly by in-migration.

Characterization of Novikoff Hepatoma Mrna Methylation and Heterogeneity in the Methylated 5′ Terminus

Abstract: KOH digestion of methyl-labeled poly(A)+ mRNA purified by (dT)-cellulose chromatography produced mononucleotide and multiple peaks of a large oligonucleotide (-6 to -8 charge) when separated on the basis of charge by Pellionex-WAX high-speed liquid chromatography in 7 M urea. Heat denaturation of the RNA before application to (dT)-cellulose was required to release contaminants (mostly 18S rRNA) that persisted even after repeated binding to (dT)-cellulose at room temperature. Analysis of the purified poly(A)+ mRNA by enzyme digestion, acid hydrolysis, and a variety of chromatographic techniques has shown that the monucleotide (53%) is due entirely to N6-methyladenosine. The large oligonucleotides (47%) were found to contain 7-methylguanosine and the 2'-0-methyl derivatives of all four nucleosides. No radioactivity was found associated with the poly(A) segment. Periodate oxidation of the mRNA followed by beta elimination released only labeled 7-methylguanine consistent with a blocked 5' terminus containing an unusual 5'-5' bond. Alkaline phosphatase treatment of intact mRNA had no effect on the migration of the KOH produced oligonucleotides on Pellionex-WAX. When RNA from which 7-methylguanine was removed by beta elimination was used for the phosphatase treatment, distinct dinucleotides (NmpNp) and trinucleotides (NmpNmpNp) occurred after KOH hydrolysis and Pellionex-WAX chromatography. Thus Novikoff hepatoma poly(A)+ mRNA molecules can contain either one or two 2'-0-methylnucleotides linked by a 5'-5' bond to a terminal 7-methylguanosine and the 2'-0-methylation can occur with any of the four nucleotides. The 5' terminus may be represented by m7G5'ppp5' (Nmp)lor2Np, a general structure proposed earlier as a possible 5' terminus for all eucaryotic mRNA molecules (Rottman, F., Shatkin, A., and Perry, R. (1974), Cell 3, 197). The composition analyses indicate that there are 3.0 N6-methyladenosine residues, 1.0 7-methylguanosine residue, and 1.7 2'-0-methylnucleoside residues per average mRNA molecule.

Modeling Arthropod Predation: Wasteful Killing by Damselfly Naiads

Abstract: A bst, act. Damselfly naiads were fed Dapliniia iniagnia in laboratory predation studies. A.lnomalagrion liastatittin predation rates were highest during the first 2 days of the penultimate instar and then declined until ecdysis. The functional response of final instar Isclinura 1rainlb)11/ii was most sensitive to changes in Daplmnia densities of 5-50/liter. Many more prey were killed than eaten in both studies; this wastefulness increased significantly as densities r-ose from 5 to 10/liter. Observations of feeding behavior revealed that damselfly naiads freqLuently strike at and capture prey and then discard them uneaten or only partially eaten. This is presumed to be the proximate cause of wasteful killing. Photographic documentation of gut contents showed that during feeding the foregut often becomes full before the midgut, leading us to hypothesize that wasteful killing occurs when hunger in the midgut motivates capture, but fullness of the foregut precludes eating. When wasteful killing is a normal component of hunger-motivated feeding behavior, it has sometimes been explained by hypothesizing the existence of a hunger threshold which is higher for eating than for capture (Holling 1966). We propose a two-gut-compartment folrmuLlation of Holling's simulation model of invertebrate predation which accounts for dynamic characteristics of wasteful killing without hypothesizing an elevated hunger threshold for eating.

Effects of Biogenic Amines and TRH on Release of Prolactin and TSH in the Rat

Abstract: The effects of a single injection of drugs on serum prolactin and TSH were determinedin male and in estrogen-primed ovariectomized rats. The precursor of serotonin, 5-hydroxytryptophan (5-HTP), produced a significant rise in serum prolactin and TSH, whereas para chloroamphetamine,a depletor of serotonin, elicited a fall in serum prolactin and TSH. α-methylmetatyrosine (α-MMT) and reserpine, both depressors of brain catecholamine (CA) and serotonin levels, evoked significant increases in serum prolactin and reductions in serum TSH. Injection of α-MMT or reserpine together with 5-HTP further elevated serum prolactin but prevented any significant change in serum TSH. This suggests that the ability of α-MMT and reserpine to inhibit TSH release is mediated through a reduction in brain serotonin and not via a decrease in CA. α-methylparatyrosine, which inhibits CA synthesis without altering serotonin, evoked a marked increase in serum prolactin but had no effect on serum TSH. L-dopa administration significantly...

1: Studies of Problem Solving, Judgment, and Decision Making: Implications for Educational Research

Abstract: Bruner (1971) quotes an aphorism he attributes to the English Platonist Weldon It is apt as a prolegomenon to this chapter: " there are three kinds of things in the world: there are troubles which we do not know quite how to handle; then there are puzzles with their clear conditions and unique solutions, marvelously elegant; and then there are problems-and these we invent by finding an appropriate puzzle form to impose upon a trouble" (p 104) Educational researchers attack problems for which convenient puzzle forms exist As evidence for this assertion, witness the continuing preoccupation with studies of paired-associate learning, adjunct questions, learning hierarchies, and social-class differences in intelligence and achievement Research typically slights the problem of how teachers think about their pupils and instructional problems; it concentrates instead on how teachers act or perform in the classroom It is our hope that by providing a number of "puzzle forms" for the study of individual judgment and problem solving, we can make it possible for more of our colleagues to pursue educational research in these areas In this chapter we shall review representative studies and theoretical proposals on thinking, human judgment, and decision making Since "judgment," "decision making," and "problem solving" are used in so many ways, the scope of our treatment will be outlined here First, the focus will be mostly

Observation of Giant Gamow-Teller Strength in ( p , n ) Reactions

Abstract: In $^{90}\mathrm{Zr}(p, n)^{90}\mathrm{Nb}$ spectra for ${E}_{p}=35 \mathrm{and} 45$ MeV, we observe a strong enhancement of the $T=4$ continuum over a range of excitation energies (full width at half-maximum of 4.2 \ifmmode\pm\else\textpm\fi{} 0.4 MeV) centered at 8.4\ifmmode\pm\else\textpm\fi{}0.3 MeV. The data are consistent with an interpretation of the broad peak as a ${(\ensuremath{\pi}{g}_{\frac{7}{2}}, \ensuremath{ u}{{g}_{\frac{9}{2}}}^{\ensuremath{-}1})}_{{1}^{+}}$ excitation wich corresponds to the giant magneticdipole resonance. Similar structure is observed near the isobaric analog state of $^{48}\mathrm{Ca}$, $^{120}\mathrm{Sn}$, and $^{208}\mathrm{Pb}$.

Ethylene-enhanced Ion and Sucrose Efflux in Morning Glory Flower Tissue.

Abstract: Rib tissue segments excised from open flowers or buds of Ipomoea tricolor Cav. and floated on aqueous media responded to ethylene treatment by rolling up after 2 to 3 hours; a simple method for quantitating the rolling up is presented. The rolling up response was temperature- and oxygen-dependent and was critically affected by the pH of the medium. The ethylene concentration giving a half-maximal response was 0.1 μl/l; continuous ethylene treatment was not required for the response as a 1-hour ethylene exposure enhanced rolling up. Rib segments rolling up during ethylene treatment unrolled when transferred to 0.5 m sucrose, indicating that rolling up was due to asymmetric turgor changes in the segments. Compartmental analysis of 36 Cl − efflux from rib segments showed a fast and a slow phase; the slow phase, with a half-time of about 6 hours, is tentatively identified as efflux from the vacuolar compartment. During ethylene treatment, the rate of 36 Cl − efflux in the slow phase rose markedly as the rolling up response developed. A similar result was obtained with the efflux of 86 Rb + . The release of 14 C-metabolites, labeled either by a period of 14 CO 2 fixation in darkness or by exposure to 14 C-(U)-glucose, also increased during ethylene-induced rolling up. These results suggest that ethylene causes an increase in membrane permeability in certain cells of the rib tissue.

Effects of hyper- and hypothyroidism on serum LH and FSH levels in intact and gonadectomized male and female rats.

Abstract: The effects of hypo- and hyper-thyroidism on serum LH and FSH were determined in both intact and castrated male and female rats. Thyro-parathyroidectomy (Tx) for 30 days in rats with intact gonads resulted in a significant reduction in serum LH and FSH, and also in a decrease in serum testosterone in males. Administration of 2.5 mug thyroxine (T4)/100 g BW to Tx rats of both sexes returned serum LH and FSH levels to those of intact rats, and in males also restored normal serum testosterone levels. Tx superimposed upon castration resulted in a significantly greater increase in serum LH and FSH than produced by castration alone. Administration of 2.5 mug T4/100 g body weight to castrate-Tx rats reduced serum LH and FSH values to those of castrate rats, whereas 10 mug T4/100 g BW evoked a further decrease in serum LH but no additional reduction in serum FSH. When both 2.5 mug T4/100 g BW and 2 mug estradiol benzoate were injected into Tx-ovariectomized rats, the decrease in serum LH and FSH was much greater than produced by T4 alone. These observations indicate that hypothyroidism results in decreased release of LH and FSH in rats with intact gonads, and in increased release of LH and FSH in castrate rats of both sexes. Administration of a replacement dose of T4 can restore LH and FSH release to normal in Tx rats with intact gonads, and to castration levels in Tx-castrate rats.