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1.
The behavior category in progress at theend of every 15 seconds of observation of chimpanzee behavior was recorded (instantaneous sampling) as was the occurrence or nonoccurrence of all defined categoriesduring every 15 second observation interval (one-zero sampling). The scores obtained using the above procedures were then correlated with the percent of net observation time, hourly rate, and mean bout duration of the behavior categories. One-zero sampling scores correlated very strongly with percent of net observation time and moderately with hourly rate and mean bout duration. Instantaneous sampling scores correlated very strongly with percent of net observation time and moderately with hourly rate and mean bout duration.  相似文献   

2.
On the use of hansen frequencies for estimating rates of behavior   总被引:1,自引:1,他引:0  
When the occurrence of a behavior is governed by aPoisson process over time, then the mean rate of behavior can be estimated usingHansen frequencies, which record whether the behavior has occurred at least once or not at all in each of several time periods. Here this estimate of the mean rate of behavior, based onHansen frequencies, is compared with the usual estimate, and its properties as an estimate of the mean rate of behavior are discussed in cases where the behavior is not governed by aPoisson process.This research was supported in part by Navy Grant N00014-67-A-0285-0009 to the Department of Statistics, University of Chicago, and by a grant from the Alfred P. Sloan Foundation to the Department of Theoretical Biology.  相似文献   

3.
Previous studies have shown that instantaneous time sampling results are more highly correlated with true duration than are one-zero sampling results. One-zero results, however, reflected a composite of both duration and frequency better than did instantaneous results. It is shown in this analysis that these outcomes are the logical result of the definitions of the two sampling modes. When interval lengths meet specific requirements, correct frequency counts can be obtained with either mode and systematic duration error with one-zero sampling can be eliminated by subtracting frequency from the number of intervals scored ‘one.’  相似文献   

4.
New record of predatory behavior by the mandrill in Cameroon   总被引:4,自引:0,他引:4  
The predatory behavior of the mandrill (Mandrillus sphinx,Linnaeus 1758), a forestliving baboon, on the bay duiker (Cephalophus dorsalis,Gray 1864) was observed under natural conditions. In the predatory episode, at least two mandrills (one adult female and one adult male) attacked a bay duiker, but no overt aggressive interactions between the attackers occurred during consumption. The estimated predation pattern based on scars—intensive attacking of the head and pulling of the hind legs to eat the thigh muscles first—resembled the predation patterns of captive mandrills observed experimentally. The findings suggest that the predatory behavior is established in mandrills as a feeding behavior pattern as in savanna-living baboons. New data are thus presented which are relevant to the discussion of the origins of hunting behavior in early hominids.  相似文献   

5.
Jiang F  Qi G  Ji Z  Zhang S  Liu J  Ma X  Chen S 《Biotechnology letters》2011,33(9):1837-1840
The glr gene, which encodes glutamate racemase involved in the conversion of l-glutamic acid to its D-isomer, was cloned and expressed in Bacillus licheniformis WX-02. Overexpression of the glr gene not only increased the production of poly-γ-glutamic acid (γ-PGA) by 22.5% but also increased the proportion of d-glutamate in γ-PGA from 77 to 85%. The activity of glutamate racemase was higher than in the original strain throughout cultivation. This is the first report that overexpression of the glr gene could enhance the l- and d-glutamate conversion in B. licheniformis WX-02 and increase the proportion of d-glutamate in γ-PGA and the yield of γ-PGA.  相似文献   

6.
The relative proportion of L-iduronic acid (IdoA) and D-glucuronic acid (GlcA) is of great importance for the structure–function relationship of chondroitin sulfate (CS)/dermatan sulfate (DS). However, determination of the isotypes of uronic acid residues in CS/DS is still a challenge, due to the instability of free uronic acid released by chemical degradation and its conversion to unsaturated uronic acid by digestion with bacterial eliminase. 1H-Nuclear magnetic resonance (NMR) spectroscopy is a promising tool with which to address this issue, but the traditional method based on the assignment of the ring proton signals of IdoA and GlcA residues still has drawbacks such as the serious overlap of signals in the 1H-NMR spectrum of CS/DS polysaccharides. We found that the proton signals of the N-acetyl group of N-acetyl-D-galactosamines in CS and DS could be clearly distinguished and accurately integrated in the one-dimensional (1D) 1H-NMR spectrum. Based on this finding, here we report a novel, sensitive, and nondestructive 1D 1H-NMR-based method to determine the proportion of IdoA and GlcA residues in CS/DS hybrid chains. The contributions of Fuchuan Li and Shuhei Yamada should be considered equal.  相似文献   

7.
Tokunaga T  Miyahara K  Tabata K  Esaka M 《Planta》2005,220(6):854-863
l-Galactono-1,4-lactone dehydrogenase (GalLDH; EC 1.3.2.3) is the last enzyme in the putative l-ascorbic acid (AsA) biosynthetic pathway of plants. Here, we show for the first time that the overexpression of GalLDH can increase AsA content in tobacco (Nicotiana tabacum L.) BY-2 cells. To see the effect, we analyzed the properties of these AsA-overproducing transgenic cell lines, especially in relation to AsA content of cells, cell division, senescence and resistance to oxidative stress. The mitotic index in AsA-overproducing cells was higher than in wild-type cells. Moreover, the browning of these cells was markedly restrained, and the proportion of dead cells was reduced, especially in the later period of culture. These AsA-overproducing cells also acquired resistance to paraquat (methyl viologen), which produces active oxygen species. These results contribute to the previous insights about AsA and raise the possibility of the generation of plants that have resistance to environmental stresses by increasing their AsA content.  相似文献   

8.
The overall excellence of the reliability of a system of behavioral observations based onGoodall's glossary of chimpanzee behavior is demonstrated, as well as the reliability of the majority of individual behaviors in the system. Non-random misclassifications are systematically analyzed to yield information on the structure of observed behavior. These findings are applied (1) to improving the system further, and (2) to assessing factors which apparently obscure distinctions between observable patterns of behavior for use in future development of observational systems.  相似文献   

9.
In this paper the display (i.e., “branch-shaking”) behavior of three troops of Japanese monkeys—the confined Oregon troop as reported byModahl andEaton (1977), the semi-free-ranging Arashiyama West troop and the free-ranging Arashiyama B troop—are compared. The comparison reveals several similarities and dissimilarities between the Oregon troop and the two genetically related Arashiyama troops. The similarities include three display postures (shaking, kicking and leaping) and an increased frequency of male but not female displaying during the breeding season. The dissimilarities include the absence of two Oregon display postures (tossing and swinging) and collective displaying among Arashiyama monkeys. The hypothesis ofModahl andEaton (1977) that male displaying influences the females' choice of male mating partners is discussed. The evidence suggests the Oregon monkeys have incorporated male displaying into their socio-sexual behavior to a greater extent than Arashiyama monkeys. However, field observations indicate that males who migrate to the Arashiyama B site during the breeding season can influence female choice by “advertizing” their location with displays.  相似文献   

10.
Bhushan R  Kumar V  Tanwar S 《Amino acids》2009,36(3):571-579
Some non-protein α-amino acids were derivatized with 1-fluoro-2,4-dinitrophenyl-5-l-alaninamide (Marfey’s reagent, MR, FDNP-l-Ala-NH2,) and four of its structural variants FDNP-l-Phe-NH2, FDNP-l-Val-NH2, FDNP-l-Leu-NH2 and FDNP-l-Pro-NH2. The resultant diastereomers were separated by normal and reversed phase thin layer chromatography (TLC) and reversed phase HPLC. In normal phase TLC, best resolution was obtained with solvent combination of phenol-water (3:1) while in reversed phase TLC mixtures of acetonitrile with triethylammonium phosphate buffer were found successful for resolution of diastereomers. The separation behavior of diastereomers prepared with different reagents was compared. The diastereomers of most of the amino acids prepared with FDNP-l-Leu-NH2 were best separated while those prepared with FDNP-l-Pro-NH2 failed to separate in most of the cases. The diastereomers were also separated on a reversed phase C8 column with gradient elution using mixture of aqueous-trifluoroacetic acid (TFA) and acetonitrile and with detection at 340 nm. The effects of TFA concentration, flow rate and run time on HPLC separation were studied.  相似文献   

11.
Cyanide inhibited d- and l-lactate and NADH oxidase activities of membrane particles from Propionibacterium shermanii but only at relatively high concentrations. Inhibition occurred at two different sites in the electron transport pathway. One site, with a half-maximal inhibition concentration (I 0.5) of 2 to 3 mM KCN, is located at the terminal oxidase involved in cytochrome b oxidation; the evidence is consistent with cytochrome d being the major oxidase involved. At high concentrations, cyanide inhibited reduction of cytochrome b by d-lactate (I 0.5 value 20–25 mM cyanide). A proportion of the oxygen-uptake remained uninhibited even by 100 mM cyanide; this proportion was about 80% for succinate, 30% for l-lactate, 15% for d-lactate and 10% for NADH. The oxygen uptake per mol of substrate oxidised increased with increasing cyanide concentration and was accompanied by the formation of hydrogen peroxide as a product of a cyanide-insensitive oxidase system.Abbreviations PMS Phenazine methosulphate  相似文献   

12.
Results of a karyological analysis of eight species collected from northeast Anatolia, Turkey are presented. The following chromosome numbers were determined:H. medianiforme (Litv. etZahn)Juxip 2n=36,H. karagollense (Zahn)P.D. Sell etC. West 2n=36,H. argillaceoides (Litv. etZahn)Juxip 2n=36,H. amblylepis Boiss. 2n=27,H. lanceolatum Vill. 2n=27,H. asterodermum (Woronow etZahn)Juxip 2n=27,H. umbellatum L. 2n=18,H. laevigatum Willd. 2n=27. The chromosome numbers of five of these seven species are presented for the first time. The results show a high proportion of triploids and tetraploids within the taxa studied.  相似文献   

13.
Broad specificity amino acid racemase (E.C. 5.1.1.10) from Pseudomonas putida IFO 12996 (BAR) is a unique racemase because of its broad substrate specificity. BAR has been considered as a possible catalyst which directly converts inexpensive l-amino acids to dl-amino acid racemates. The gene encoding BAR was cloned to utilize BAR for the synthesis of d-amino acids, especially d-Trp which is an important intermediate of pharmaceuticals. The substrate specificity of cloned BAR covered all of the standard amino acids; however, the activity toward Trp was low. Then, we performed random mutagenesis on bar to obtain mutant BAR derivatives with high activity for Trp. Five positive mutants were isolated after the two-step screening of the randomly mutated BAR. After the determination of the amino acid substitutions in these mutants, it was suggested that the substitutions at Y396 and I384 increased the Trp specific racemization activity and the racemization activity for overall amino acids, respectively. Among the positive mutants, I384M mutant BAR showed the highest activity for Trp. l-Trp (20 mM) was successfully racemized, and the proportion of d-Trp was reached 43% using I384M mutant BAR, while wild-type BAR racemized only 6% of initial l-Trp.  相似文献   

14.
Summary When monolayer cultures of Chinese hamster ovary cells were exposed to3H-glycerol ranging in concentration from 0.1 m to 200mm, glycerol influx was found to increase in direct proportion to the extracellular concentration of glycerol. Other experiments indicated that the same relationship existed at concentrations in excess of 1.0m. Similarly, glycerol efflux was found to vary in direct proportion to the intracellular concentration of glycerol. In neither case could influx or efflux be saturated,. Glycerol influx was not affected by depletion of ATP, alkylation by parachloromercuribenzene sulfonic acid, or exposure to persantine. Altering the pH or temperature also had little effect. Attempts at demonstrating countertransport of glycerol were negative. These data indicate that glycerol probably passes through the membrane by a nonmediated process. For cells in monolayer, the kinetics of influx and efflux are biphasic. Similar biphasic kinetics are observed with cells in suspension culture. A close fit to the data may be obtained by adding together two first-order curves. The pair of curves for influx are clearly different from the pair for efflux. The fit provided by the two pairs of first-order functions suggested that glycerol might diffuse into and out of two intracellular compartments. However, the experimental data do not agree with the predicted behavior of a two-compartment system. As a result, the exact nature of the diffusion limiting steps which are described by the first-order equations remains undefined.  相似文献   

15.
Kaplan andZucker (1980) argued that dominance and kinship do not function as important organizing features for intragroup behavior and social structure among patas monkeys (Erythrocebus patas). This paper reviews the available data pertinent to this argument and concludes that dominance probably is not a reliable structural variable for captive patas, despite its clear development in most groups. In contrast, kinship is a major organizing feature that strongly affects allogrooming and other affiliative interactions, and socialization.  相似文献   

16.
Epilepsy is a serious neurological disorder with neuronal loss and spontaneous recurrent seizures, but the neurochemical basis remains largely unclear. We hypothesize that d-serine, a newly identified endogenous co-agonist of N-methyl-d-aspartate (NMDA) receptor, may trigger excitotoxicity and neuronal damage in epileptogenesis. By using a mouse pilocarpine model, immunohistochemistry, Fluoro-Jade staining and double-labeling, the present study revealed up-regulation of d-serine expression in a proportion (41%) of neurons in the cerebral cortex and hippocampus. The d-serine-positive neurons occurred at 4 h, reached peak levels at 12–24 h, and gradually went down at 3–14 days. Moreover, most of d-serine-positive neurons were GABAergic (98%), underwent degenerating death (93%), and were accompanied enhancing phosphorylation of NMDA receptor subunit 1. This study has provided new evidence that up-regulation of d-serine production might induce GABAergic neuronal degeneration through excitotoxic mechanism in the pilocarpine model and may be involved in early pathogenesis and recurrent seizure of chronic epilepsy. Ms. L. Wang is on leave from Department of Neurology, Kunming General Hospital of Chengdu Military Region, China.  相似文献   

17.
Indole-3-acetic acid (IAA) and its putative precursors, l- and d-tryptophan, indole-3-pyruvate, and tryptamine were isolated from tomato (Lycopersicon esculentum (L.) Mill.) shoots, identified by mass spectrometry, and measured using capillary gas chromatography with an electron capture detector and radioactive internal standards. Average amounts present were 7.9ng · (g FW)–-1 IAA, 5.7ng · (g FW)–-1 indole-3-pyruvate, 132 ng · (g FW)–-1 tryptamine, 103 ng · (g FW)–-1 d-tryptophan, and 2250 ng · (g FW)–-1 l-tryptophan. Indole-3-acetaldoxime was not found; detection limits were less than 1ng · (g FW)–-1. When tomato shoots were incubated for 6, 10 and 21 h in 30% –2H2O, up to four positions in IAA, l- and d-tryptophan, tryptamine and indole-3-pyruvate became labelled with –2H. Compounds became labelled rapidly with 10% of IAA molecules containing –2H after 6 h. The percentage of labelled molecules of IAA and l-tryptophan increased up to 10 h but then decreased again, correlating with an increase in the total shoot tryptophan and presumably a result of protein hydrolysis in the excised, slowly senescing tissue. The amount of –2H in d-tryptophan also showed an increase followed by a decrease, but the proportion of labelled molecules was much less than in l-tryptophan and IAA. Tryptamine became labelled initially at a similar rate to IAA but continued to accumulate –2H up to 21 h. We conclude that tryptamine is synthesized from a different pool of tryptophan from that used in IAA synthesis, and is not a major endogenous precursor of IAA in tomato shoots. Indole-3-pyruvate was the most heavily labelled compound after 6 and 10 h incubation (21-h data not available). Furthermore, the proportion of –2H-labelled indole-3-pyruvate molecules was quantitatively consistent with the amount of label in IAA. On the other hand, a quantitative comparison of the IAA turnover rate and the rate of –2H incorporation into both l- and d-tryptophan indicates that IAA is not made from the total shoot pool of either l- or d-tryptophan. Instead IAA appears to be synthesized from a restricted pool which is turning over rapidly and which has access to both newly synthesized tryptophan and that from protein hydrolysis.Abbreviations GC-ecd gas chromatography with electroncapture detector - GC-MS combined gas chromatography-mass spectrometry - HPLC high-performance liquid chromatography - IAA indole-3-acetic acid - IAOX indole-3-acetaldoxime - IPyA indole-3-pyruvate - PFB pentafluorobenzyl - RT retention time - TNH2 tryptamine - Trp tryptophan - SIM selected ion monitoring We wish to thank Ms. Sue Alford for running the mass spectra and Dr Harry Young for advice with the mass spectrometry. The work was supported by grants from the University of Auckland Research Committee and the C. Alma Baker Trust fund. The mass spectrometer was supported jointly by the University Grants Commitee (NZ) and the DSIR Division of Horticulture and Processing.  相似文献   

18.
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   

19.
Summary The behavior of nucleoids during the leucoplast division cycle in the epidermis of onion (Allium cepa) bulbs was investigated using DNA-specific fluorochrome 4'6-diamidino-2-phenylindole (DAPI) staining. The leucoplast was morphologically amoeboid and continuously changed its shape. A dumbbell-shaped leucoplast divided into two spherical daughter ones by constriction in the middle region of the body. Leucoplasts contained 4–10 mostly spherical, oval, partly rodand dumbbell-shaped nucleoids which were dispersed within the bodies. The proportion of one DNA molecule of a T4 phage particle to the small leucoplast nucleoid in the grain density of negative film was 1 to 0.91. Comparison of the present result and another groups' biochemical results suggested that a small leucoplast nucleoid contains one DNA molecule. The dumbbell-shaped leucoplast probably before division contained about twice as many nucleoids as the spherical leucoplast after division, and each half of the dumbbell contained about half the number of nucleoids. Nucleoids increased in number with growth of the leucoplast. The behavior of nucleoids during the leucoplast division cycle in onion bulbs was basically similar to that during the chloroplast division cycle in higher plants and green algae, which was previously reported (Kuroiwa et al. 1981 b).  相似文献   

20.
Recently, we reported that intracerebroventricular (i.c.v.) injection of l-alanine attenuated the stress response under an acute stressful condition in chicks. However, no information of l-alanine was available for the influence on energy expenditure and changes in the posture under stressful conditions. The purpose of the present study was to clarify whether central l-alanine affects heat production (HP) of neonatal chicks, and whether HP is correlated with the behavior after isolation-induced stress. The i.c.v. injection of l-alanine (0.8 μmol) decreased oxygen consumption, carbon dioxide production and HP shortly after injection. Central l-alanine reduced the posture for active wakefulness, but increased the posture for sitting motionless with head drooped (sleeping posture). The present study demonstrates that central l-alanine decreases energy expenditure and causes a hypnotic effect in chicks exposed to an acute stressful condition.  相似文献   

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