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1.
Observations of monkey behavior were made on free-ranging and corral-enclosedMacaca mulatta. Two sampling techniques were used: focal animal and group observations. Group observations measured frequencies of social behavior whereas focal observations used time samples which estimated durations of social and nonsocial activities as well as frequencies of social behavior. Analysis of concordance within and between sampling techniques revealed that short duration focal time samples provide a reliable estimate of total frequencies of social behaviors derived using group observations and furthermore, allows the recording of important nonsocial activities not easily recorded in terms of frequencies. Focal time sampling is advantageous for certain types of studies where the equal distribution of observation time between individuals is important, particularly in the field where visibility is often limited and individuals can only be observed continuously for short periods of time. This work was supported by grants from the H. F. Guggenheim Foundation, Dr.H. C. Robinson, Jr., and USPHS grants MH 24607 and MH 25642.  相似文献   

2.
The paper examinesBateson’s idea that social relationships can be described according to the degree that behavior is symmetric (mutual) or complementary (non-mutual). It was suggested that in primates complementary relationships are most typical and stable.Bateson’s definitions were quantified and applied to observations of paired rhesus females, showing that familiar dyads had complementary relationships, probably reflecting social status, while unfamiliar dyads had symmetric relationships. Phases of this project were supported by U. S. P. H. S. grants, MH-17052 (toE. W. Hansen) and MH-00322 (Postdoctoral Fellowship).  相似文献   

3.
III Conclusion and Summary Zygosaccharomyces Marxianus andSaccharomyces macedoniensis belong to the same species. This species is met with in the haplophase (Z. Marxianus) as well as in the diplophase (S. macedoniensis). It was possible to bring this yeast from the haplophase into the diplophase and vice versa. By keeping this yeast during long times on maltagar it showed a tendency to change from the haplophase into the diplophase, but not into the opposite direction.It seems quite possible thatHansen, who did not describe a conjugation in this yeast, had met with the diplophase.It has been once more emphasized — at whichWinge andLaustsen and alsoLindegren andLindegren have pointed —, that the genusZygosaccharomyces is no valid genus.The yeast studied here belongs to the genusSaccharomyces and must be designated with the original name given to it byHansen:Saccharomyces Marxianus.For the sake of completeness it is mentioned here that also an imperfect stage ofS. Marxianus has been describedviz., Candida macedoniensis (A. Castellani) Berkhout (I).Saccharomyces fragrans Beijerinck has to be considered as its synonym.  相似文献   

4.
Summary Breathing frequencyF r of resting blue-naped mousebirdsUrocolius macrourus lies between 50–70 per min and correlates directly with ambient temperatureT a and energy metabolismM. The nocturnal mean energy intake per breath varies between 5.6–17.7 mJ/g. At highT a the birds show gular fluttering with a relatively constantF r of about 460 min–1.M shows a constant absolute day-night difference of 25 J/g·h; the relative differences areT a-dependent between 36–168% (lower values at lowerT a). Thermal conductance is 2.10–2.15 J/g·h·°C (predicted 2.67), indicating a good insulation. Basal metabolic rate BMR is reduced by 63% compared to predicted values. At aT a-range of +8–36 °C the birds are normothermic. Below this range nocturnalT b andM decrease slightly with fallingT a. The birds show partial heterothermia (shallow hypothermia). Clustering is an effective energy saving strategy which allows loweringM with keeping highT b even at lowT a.Oxygen-intake is controlled byF r as well as by tidal volumeV t inT a-dependent changing portions.V T can vary between 0.29–0.91 ml (mean value 49.7 ml).Abbreviations T a ambient temperature - T b body temperature - M energy metabolism - F r breathing frequency - V T tidal volume - BMR basal metabolic rate - TNP thermoneutral point  相似文献   

5.
We investigated the block of KATP channels by glibenclamide in inside-out membrane patches of rat flexor digitorum brevis muscle. (1) We found that glibenclamide inhibited KATP channels with an apparent K i of 63 nm and a Hill coefficient of 0.85. The inhibition of KATP channels by glibenclamide was unaffected by internal Mg2+. (2) Glibenclamide altered all kinetic parameters measured; mean open time and burst length were reduced, whereas mean closed time was increased. (3) By making the assumption that binding of glibenclamide to the sulphonylurea receptor (SUR) leads to channel closure, we have used the relation between mean open time, glibenclamide concentration and K D to estimate binding and unbinding rate constants. We found an apparent rate constant for glibenclamide binding of 9.9 × 107 m −1 sec−1 and an unbinding rate of 6.26 sec−1. (4) Glibenclamide is a lipophilic molecule and is likely to act on sulfonylurea receptors from within the hydrophobic phase of the cell membrane. The glibenclamide concentration within this phase will be greater than that in the aqueous solution and we have taken this into account to estimate a true binding rate constant of 1.66 × 106 m −1 sec−1. Received: 7 July 1996/Revised: 4 October 1996  相似文献   

6.
Summary Chrysophyceae from Lake Stråken, Aneboda, Sweden, have been examined by electron microscopy. 10 species ofChrysophyceae were found, and electron micrographs of their silica scales are given. 6 of these taxa have not previously been recorded from Sweden, viz.Chrysosphaerella multispina Bradley,Mallomonas crassisquama (Asmund)Fott,Mallomonas papillosa Harris &Bradley,Synura echinulata Korshikov, andSynura spinosa Korshikov f.spinosa Petersen &Hansen.Dedicated to Professor L.Geitler on the occasion of his 70th birthday.  相似文献   

7.
Mother-infant separation in rhesus monkey living in natural environment   总被引:1,自引:1,他引:0  
Four mothers were separated from the infants in two free-ranging groups of rhesus monkeys. Infants were observed for three stages i.e. pre-separation, separation, and post-separation. Separation caused a marked decrease in play in the infant. Crying and restlessness increased. During post-separation, a significant increase in mother's approach behaviour towards the infant was observed. The results of the present field study almost resemble the results of laboratory studies done bySeay, Hansen, andHarlow (1962).  相似文献   

8.
Chlamydomonas reinhardtii chloroplasts catalyzed two sequential steps of Chl biosynthesis, S-adenosyl-l-methionine:Mg-protoporphyrin IX methyltransferase and Mg-protoporphyrin IX monomethyl ester oxidative cyclase. A double mutant strain of C. reinhardtii was constructed which has a cell wall deficiency and is unable to form chlorophyll in the dark. Dark-grown cells were disrupted with a BioNeb nebulizer under conditions which lysed the plasma membrane but not the chloroplast envelope. Chloroplasts were purified by Percoll density gradient centrifugation. The purified chloroplasts were used to define components required for the biosynthesis of Mg-2,4-divinylpheoporphyrin a 5 (divinyl protochlorophyllide) from Mg-protoporphyrin IX. Product formation requires the addition of Mg-protoporphyrin IX, the substrate for S-adenosyl-l-methionine:Mg-protoporphyrin IX methyltransferase which produces Mg-protoporphyrin IX monomethyl ester. The Mg-protoporphyrin IX monomethyl ester that is generated in situ is the substrate for Mg-protoporphyrin IX monomethyl ester oxidative cyclase. The reaction product was identified as Mg-2,4-divinylpheoporphyrin a 5 (divinyl protochlorophyllide) by excitation and emission spectrofluorometry and HPLC on ion-paired reverse-phase and polyethylene columns. Mg-2,4-divinylpheoporphyrin a 5 formation by the coupled enzyme system required O2 and was stimulated by the addition of NADP+, an NADPH regenerating system, and S-adenosyl-l-methionine. Product was formed at a relatively steady rate for at least 60 min.Abbreviations MgDVP Mg-2,4-divinylpheoporphyrin a 5 (divinyl protochlorophyllide) - SAM S-adenosyl-l-methionine  相似文献   

9.
Summary Population and family studies have confirmed the existence of a plasma a-l-fucosidase polymorphism in humans and the autosomal recessive inheritance of the low activity trait. The frequency of the latter is estimated at 11%. The low activity individuals or variants can also be distinguished by the fact that their plasma a-l-fucosidase is heat-inactivated at acidic pH. Sucrose gradient centrifugation results indicate the transition of non-variant plasma a-l-fucosidase with a molecular weight of 66,000 at pH 8.4 to an enzyme form with a molecular weight of 193,000 at pH 3.0. The former is thermolabile, the latter thermostable. Interconversion is pH-dependent. It is hypothesized that the non-variant enzyme, a monomer at alkaline pH, changes upon acidification into a trimeric conformation via dimerization. The thermolabile variant a-l-fucosidase monomer is not converted into a trimer, but only partially into a dimer.  相似文献   

10.
Summary A number of published data suggest a variable stoichiometry between the rates of cellular potassium uptake and net sodium transport (J Na) across the urinary bladder of the toad. This problem was examined by simultaneously studying the intracellular chemical activity of potassium (a K) with open-tip K+-selective microelectrodes and micropipets, and monitoringJ Na by measuring the short-circuit current (SCC). When bathed in the short-circuited state with solutions containing ana K of 2.7mm, the mean ±sem values for intracellulara K were 43±0.6mm.Ouabain, at a concentration of 10–2 m, reduced intracellulara K by 56–67% and SCC by 96–100%. At 5×10–4 m, ouabain reversibly reduced intracellulara K by 40–55%, and SCC by 63–68%; the inhibition of SCC was only partly reversible during the period of observation.Removal of external potassium reduced intracellulara K by 69–80% and SCC by 51–76%. Restoration of external potassium entirely returned intracellulara K to its control value, but only partially reversed the inhibition of SCC during the period of study. Furthermore, recovery ofa K began 19–43 min before that of SCC; recovery ofa K was 90–97% complete before any increase in SCC could be measured. Although other interpretations are possible, the simplest interpretation of the data is that the processes responsible for potassium accumulation and transepithelial sodium transport are not identical. We propose the existence of a separate transfer mechanism at the basolateral cell membrane, responsible for accumulating intracellular potassium, and not directly coupled to active sodium transport.  相似文献   

11.
From a monthly survey over a ten-year period (1983–1992) of the Ishitegawa Reservoir, Japan, two multiple regression equations describing the mean chlorophylla (Chl-a) concentration at 0.5 m depth during July, August and September (C S ) and the maximum Chl-a concentration in the photic zone, including its subsurface maximum during this period (C M ), were obtained. The conductivity at 0.5 m depth in May and the mean air temperature during May or during May and June were used as independent variables. These equations were calculated using seven years of data (1983–1988 and 1992). From 1989 to 1991 two impermeable plastic-coated sheet fences were installed across the upper end of the reservoir along the top 5 m of water column. The equations were used to determine the effectiveness of this flow regulation on the summer Chl-a concentration. In 1989 and 1991, when the fences were in place from June to August, no effects were found on the observed C S and C M values. In 1990, when the fences had been in place since October 1989, the observed values were lower than the predicted values.  相似文献   

12.
Summary Optimization of d-(-)-2,3-butanediol production from the Jerusalem artichoke, Helianthus tuberosus, by Bacillus polymyxa ATCC 12 321 is described. The effects of initial sugar concentration and oxygen transfer rate were examined. The latter appears to be the most important parameter affecting the kinetics of the process. The best results (44 g·l-1 2,3-butanediol, productivity of 0.79 g·l-1·h-1) were obtained by setting an optimal k L a profile during batch culture.  相似文献   

13.
Summary Atwood'S method was used for scoring recessive lethals in aNeurospora heterokaryon with an amycelial component. Conidia were stored dry at 30° and 4°C, and samples were tested for lethals every few weeks over a period of 7 months. At 30°, lethals accumulated in strictly linear proportion with time, at a rate of 0.3% lethals per week. At 4°, the rate of accumulation was much slower; the data are not sufficient to decide whether it was linear. When conidia that had spent 24 weeks at 4° were transferred to 30°, the proportion of lethals increased steeply to the level that had meanwhile been reached in the warm series. This points to the possibility of resolving the mutational process into successive steps with different temperature coefficients. Reasons are given for presuming that none of the lethals had been present in the culture of origin and for excluding their occurrence through errors of gene replication during storage or on the plates.When samples of conidia from the warm series were inserted into growth tubes, 80% or more of the accumulated lethals were lost during the initial stages of growth. Subsequently, lethals accumulated again at a rate that remained constant for at least 2 weeks. This, together with similar observations byAtwood andPittenger (1955), opens the possibility of studying mutation rates during growth in growth tubes.Operated by Union Carbide Corporation for the United States Atomic Energy Commission.Work carried out while the author was a Visiting Investigator at Oak Ridge National Laboratory on leave of absence from Edinburgh University.  相似文献   

14.
Summary In hanging-drop cultures of dental pulp of the permanent canines and molars of newborn kittens, outgrowth of dentinal fibers from the outer surface of young dentin was observed when the enamel organ was removed.The outgrowth started soon after explantation and the fibers reached a considerable length in a short period of time.Outgrowing fibers were not ramified, but usually showed a knot near their distal end.The potency of growth at the peripheral end of the dentinal fibers was positively established.This investigation was supported by the Medical Research and Development Board, Office of the Surgeon General, Department of the Army, under Contract Nos. DA-49-007-MD-447 and DA-49-007-MD-32, administered by Doctors T. G. Blocker, jr. and C. M. Pomerat respectively.  相似文献   

15.
Summary The discovery of the hidden, built-in macroconidia in the four members of the Faviform Group of the dermatophytes, i.e.,Achorion schoenleinii, Trichophyton violaceum, Trichophyton verrucosum andMicrosporon ferrugineum, is described.To bring the hidden, built-in macroconidia to full fructification, i.e., to force the production of imperfect and perfect organs of fructification (macroconidia, cleistothecia), two entirely different techniques have been used: 1) the hair-soil method, 2) the yeast extract method.The two techniques, entirely independent from each other, yielded the same result: the ancestral form of the four members of the Faviform Group of dermatophytes. The imperfect form is described asFavomicrosporon pinettii,Benedek, 1965, sp. nov. The perfect form isAnixiopsis stercoraria (Hansen)Hansen, 1897.The ancestral form was found not only in and cultured from the strains of those dermatophytes derived from pathological material, but it was also recovered from its saprophytic habitat, from the soil (potting soil).
Zusammenfassung Die Entdeckung der verborgenen, eingebauten Makrokonidien in den vier Representanten der Faviformen Gruppe der Dermatophyten, i.e.Achorion schoenleinii, T. violaceum, T. verrucosum, Microsporon ferrugineum, wird beschrieben.Um die verborgenen, eingebauten Makrokonidien zur vollen Fruchtbildung zu bringen, i.e. um die Produktion der imperfekten und perfekten Organe der Fruktifikation (Makrokonidien, Kleistothecien) zu erzwingen, sind zwei völlig verschiedene Methoden benutzt worden: 1) die Haar-Erde-Methode, und 2) die Hefeextrakt-Methode.Beide Methoden, völlig unabhängig von einander, haben zu demselben Ergebnis geführt, i.e. zur Entdeckung der Urform von den vier Representanten der Faviformen Gruppe der Dermatophyten. Die imperfekte Form wird alsFavomicrosporon pinettii,Benedek, 1965, sp. nov. beschrieben. Die perfekte Form istAnixiopsis stercoraria (Hansen)Hansen, 1897.Die ancestrale Form wurde nicht nur aus den Stämmen jener Dermatophyten gezüchtet, die aus pathologischen Produkten gewonnen worden sind, sondern auch aus dem natürlichen Habitat: von der Erde (potting soil).

Résumé La découverte des macroconidies occultes et encastrées dans les quatre membres du Groupe Faviforme des dermatophytes:Achorion schoenleinii, Trichophyton violaceum, Trichophyton verrucosum etMicrosporon ferrugineum, est décrite.Pour forcer les macroconidies occultes et encastrées à la fructification complète, i.e. de produire des organs de reproduction imparfaits et parfaits, macroconidies et cleistothecia, on a fait l'usage de deux techniques complètement différentes: 1) des cheveux sur sol et 2) de l'extraction de levure.Toutes les deux méthodes, complètement indépendantes l'une de l'autre, ont produit le même résultat: la forme ancestrale des quatre membres de la Groupe Faviforme des dermatophytes. La forme imparfaite est décrite commeFavomicrosporon pinettii,Benedek, 1965, sp. nov. et la forme parfaite commeAnixiopsis stercoraria (Hansen)Hansen, 1897.La forme ancestrale a été trouvée non seulement dans les souches des dermatophytes indiquées et en cultivées, provenantes des produits pathologiques, mais aussi du sol, du terrain jardinier.
  相似文献   

16.
392 random patients treated with SCC prior to surgery were assayed for pseudocholinesterase activity and electrophoretic pattern. The estimate of the percent frequencies of theE 1 a allele were 1.16±0.38 and of the C5 (+) phenotype 9.7±1.5, both typical of Caucasian populations. By combining the presentE 1 a gene frequency estimate with that from another sample of the same population (Cermele et al., 1987) a better estimate with smaller confidence limits was obtained, that is: 1,14±0,27. One subject interpreted asE 1 a E 1 a on phenotypic grounds was also found (expected 0,05) in this random sample. A correlation coefficient of −0.521 was found between E activity and myorelaxation time in the whole sample. High correlation values (r=−0.55 and r=−0.46) were found forE 1 u E 1 u ; C5 (−) andE 1 u E 1 u ; C5 (+) individuals, respectively, showing a strong dependence of the latter variable on the former one even within apparently homogeneous classes. The use of the product of these two variables as a classification criterion allowed the identification of a subject with very long myorelaxation time but normal activity.  相似文献   

17.
Sugar substrates which depress the intracellular level of inorganic phosphate in baker's yeast (d-glucose,d-fructose,d-mannose, sucrose, as well as maltose andd-galactose after appropriate induction) also make transmembrane flux of phosphate anions possible. Acetate and ethanol, although readily oxidized, as well as nonmetabolized sugars, do not produce the effect. Phosphate uptake in whole cells (but not in protoplasts) is accelerated by preincubation with substrate either aerobically or anaerobically but the actual presence of substrate in the incubation medium is required for transport to take place. Starved cells take up phosphate from the medium with aK m of 3mm, the half-activation concentration by glucose being 18mm, the amount taken up being constant under given conditions (40 μmol/g dry wt. here). Phosphate-rich cells lose phosphate to the medium in the presence of a suitable substrate. The uptake process is characterized by an activation energy of 13400 cal/mol at 10−6 m phosphate and of 9400 cal/mol at 10−3 m phosphate. The process shows two optima at pH 5.0 and 7.0. A short-lived intermediate of fermentative sugar metabolism is postulated as essential for the translocation of phosphate across the yeast membrane.  相似文献   

18.
Summary The effects of ambient temperature (T a) on ventilation and gas exchange in chukar partridges (Alectoris chukar) were determined after acclimation to low and high altitute (LA and HA; 340 and 3,800 m, respectively).At both LA and HA, oxygen consumption ( ) increased with decreasingT a atT a from 20 to –20°C. AtT a of 35 to 40°C, increased above thermoneutral values at HA but remained constant and minimal at LA. Water loss rates increased rapidly atT a>30°C at both altitudes as birds began to pant. Ventilation rates (f) during panting were 5-to 23-fold greater than the minimalf at thermoneutralT a.Increased atT a below thermoneutrality was supported by increased minute volume (V i) at both altitudes. The change inV i was primarily a function of changing tidal volume (V t), althoughf increased slightly asT a declined. Oxygen extraction ( ) remained fairly constant atT a below 20°C at both altitudes. BothV t and were considerably lower when birds were panting than at lowerT a.Chukars showed few obvious ventilatory adaptations to HA. The 35% change in between 340 and 3,800 m was accommodated by a corresponding change inV i (btps), most of which was accomplished by increasedf at HA, along with a slight increase in .Abbreviations and symbols HA high altitude - LA low altitude - rate of evaporative water loss - oxygen extraction efficiency - f respiratory frequency - V t tidal volume - V i minute volume - BMR basal metabolic rate - MHP metabolic heat production  相似文献   

19.
Summary The production of l-phenylalanine from the racemate d,l-phenyllactate in an enzyme membrane reactor has been examined. In a first step the racemate is dehydrogenated to the prochiral intermediate phenylpyruvate by the enzymes d-and l-hydroxyisocaproate dehydrogenase. In a second step phenylpyruvate is reductively aminated to l-phenylalanine by l-phenylalanine dehydrogenase. Both steps are dependent on coenzyme, the first one requires NAD, the second one NADH in stoichiometric amounts; in this way the coenzyme is regenerated and only required catalytically. The coenzyme is covalently bound to polyethylene glyco-20 000 and can thus be retained in the reactor analogously to the three enzymes. In order to optimize the continuous production of l-phenylalanine from d,l-phenyllactate, models of the reaction kinetics and of the reactor system have been set up. By means of the reactor model, we can calculate the optimum ratio of the three enzymes, the optimum coenzyme concentration and the optimum phenylpyruvate concentration in the feed.In this process, at a substrate concentration of 50 mM d,l-phenyllactate we reached a spacetime-yield of 28 g l-Phe/(l*d).Abbreviations PEG polyethylene glycol - d-HicDH d-hydroxyisocaproate dehydrogenase - l-HicDH l-hydroxyisocaproate dehydrogenase - PheDH l-phenylalanine dehydrogenase - V max maximum velocity - K M Michaelis-Menten constant - K l inhibition constant - R1 reaction rate of the d-HicDH forward reaction - R2 reaction rate of the d-HicDH reverse reaction - R3 reaction rate of the l-HicDH forward reaction - R4 reaction rate of the l-HicDH reverse reaction - R5 reaction rate of the PheDH forward reaction - R6 reaction rate of the PheDH reverse reaction - d-PLac d-phenyllactate - l-PLac l-phenyllactate - PPy phenylpyruvate - l-Phe l-phenylalanine - NH4 ammonium - residence time  相似文献   

20.
An intrinsic property of human motor behavior is a trade-off between speed and accuracy. This is classically described by Fitts’ law, a model derived by assuming that the human body has a limited capacity to transmit information in organizing motor behavior. However, Fitts’ law can also be realized as an emergent property of movements generated by delayed feedback. In this article, we describe the relationship between the Fitts’ law coefficients and the physiological parameters of the underlying delayed feedback circuit: the relaxation rate or time constant, and the psychomotor delay of the feedback process. This relationship is then used to estimate the motor circuit delay of several tasks for which Fitts’ law data are available in the literature. We consistently estimate the delay to be between 0 and 112 ms. A further consequence of this model is that not all combinations of slope and Y-intercept in Fitts’ law are possible when movements are generated by delayed feedback. In fact, it is only possible for an observed speed–accuracy trade-off to be generated by delayed feedback if the Fitts’ law coefficients satisfy ?0.482 ≤ a/b ≤ 3.343 [bits] where b represents the slope in bits per second and a represents the Y-intercept in seconds. If we assume human movement is generated by delayed feedback, then the Fitts’ law coefficients should always be restricted to this range of values.  相似文献   

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