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By using a large cage in the field and a system of marking, the flight activities of 36 females and 49 males of the European chafer were followed during June and July, 1954.It was found that the beetles made one to 11 flights during their life span with males averaging five flights and females 4.5. More males made eight to 11 flights than did females, and males made more flights on consecutive evenings. The average longevity of the males was found to be six days while the females lived on the average for 6.5 days.The main flight period of the European chafer lasts about one month though some beetles can be observed flying in the evenings for about two months after the main flight has ended. The populations observed in the field are composed of successive groups of beetles which emerge, fly for several days then die. These groups overlap each other so that high numbers of beetles are present in the trees each evening during the main flight period. Variations in the physical characteristics of the soil habitat could be responsible for the differences in the time of maturity of the larvae and the subsequent first-time emergence of the adults.
Zusammenfassung Im Juni und Juli 1954 wurde die Flugtätigkeit von 36 weiblichen und 49 männlichen Tieren von Amphimallon majalis (Razoumowsky) unter Zuhilfenahme eines grossen Käfigs im freien Felde und eines geeigneten Bezeichnungssystems der Tiere verfolgt.Es zeigte sich, dass die Käfer während ihrer Lebensdauer ein bis elf Flüge unternehmen und zwar betrug der Durchschnitt für männliche Tiere fünf, für weibliche 4,5 Flüge. Mehr Männchen als Weibchen flogen 8 bis 11 mal und die Männchen flogen häufiger an aufeinanderfolgenden Abenden. Für männliche Käfer war die durchschnittliche Lebensdauer 6 Tage, während die weiblichen einen Durchschnitt von 6,5 Tagen erreichten.Die Hauptflugperiode von Amphimallon majalis erstreckt sich über etwa einen Monat, obwohl man auch 2 Monate lang nach der Hauptflugzeit des abends noch einige Käfer fliegen sehen kann. Die Gesamtzahl der im Versuchsfeld beobachteten Insekten setzt sich aus auf einander folgenden Gruppen von Käfern zusammen, die nach einander ausschlüpfen, mehrere Tage fliegen und dann sterben. Diese Gruppen überschneiden sich, so dass während der Hauptflugzeit abends eine grosse Anzahl von Käfern in den Bäumen zu finden ist. Es ist sehr wohl möglich, dass Unterschiede in der physikalischen Beschaffenheit des Bodens für die Länge der Reifezeit der Larven verantwortlich sind und somit auch für den Zeitpunkt des Erstfluges der entwickelten Käfer.相似文献
85.
Strangers Abroad Series: Sir Walter Baldwin Spencer (1860–1929), Fieldwork; Franz Boas (1858–1952), The Shackles of Tradition; William Rivers (1864–1922), Everything Is Relatives; Bron-islaw Malinowski (1884–1942), Off the Verandah; Margaret Mead (1901–1978), Coming of Age; Sir Edward Evans-Pritchard (1902–1973), Strange Beliefs. 相似文献
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Taffet George E.; Michael Lloyd A.; Tate Charlotte A. 《Journal of applied physiology》1996,81(4):1488-1494
Taffet, George E., Lloyd A. Michael, and Charlotte A. Tate.Exercise training improves lusitropy by isoproterenol in papillarymuscles from aged rats. J. Appl.Physiol. 81(4): 1488-1494, 1996.Aging isassociated with a decreased cardiac responsiveness to -adrenergicstimulation. We examined the effect of endurance exercise training ofold Fischer 344 male rats on -adrenergic stimulation of the functionof isolated left ventricular papillary muscle. Three groups wereexamined: sedentary mature (SM; 12-mo old), sedentary old (SO;23-24 mo old), and exercised old (EO; 23-24 mo old) that weretreadmill trained for 4-8 wk. The isometric contractile propertieswere studied at 0.2 Hz and 0.75 mM calcium. Without -adrenergicstimulation, there were no group differences for peak tension, maximumrate of tension development(+dP/dt), or maximum rateof tension dissipation(dP/dt). The time to peak tension was longer (P < 0.05) forboth EO and SO than for SM rats. Half relaxation time(RT1/2) was prolonged(P < 0.05) for SO compared with SMand EO (which did not differ). The three groups did not differ in the-adrenergic stimulation by isoproterenol of peak tension,dP/dt, time to peak tension, orcontraction duration. The inotropic response(+dP/dt) of SM was greater(P < 0.05) than that in SO or EOrats (which did not differ); however, the lusitropic response(RT1/2) was lesser(P < 0.05) in SO than in SM or EO rats (which did not differ). Thus exercise training of old rats improved the lusitropic response to isoproterenol without altering theage-associated impairment in inotropic response. 相似文献
88.
Timothy Wachs Robin L. Sheppard Jack Henion 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,685(2):548
A simple self-aligning liquid junction-electrospray interface for coupling a capillary electrophoresis (CE) system to an atmospheric pressure ionization (API) mass spectrometer (CE-MS) was developed. In contrast to previous liquid junction interfaces, the self-aligning liquid junction interface simplifies the precise alignment of the CE capillary and the sprayer needle and uses a positive make-up flow. Several capillary CE-MS applications were run using both the self-aligning liquid junction interface and the widely used sheath flow interface for comparison purposes. The electrospray stability of the self-aligning liquid junction interface is consistently better even when non-volatile electrolyte solutions are used. At first, some band broadening was obtained with the self-aligning liquid junction interface. Experiments with different CE buffer systems suggested that this band broadening was caused by the materials used in constructing the interface. By using a more inert material for the sprayer needle, the self-aligning liquid junction exhibits excellent electrophoretic resolution, comparable sensitivity, and higher signal-to-noise ratios when run under the same conditions as the sheath flow interface. 相似文献
89.
OBJECTIVE: To compare the efficacy and acceptability of ethamsylate, mefenamic acid, and tranexamic acid for treating menorrhagia. DESIGN: Randomised controlled trial. SETTING: A university department of obstetrics and gynaecology. SUBJECTS: 76 women with dysfunctional uterine bleeding. INTERVENTIONS: Treatment for five days from day 1 of menses during three consecutive menstrual periods. 27 patients were randomised to take ethamsylate 500 mg six hourly, 23 patients to take mefenamic acid 500 mg eight hourly, and 26 patients to take tranexamic acid 1 g six hourly. MAIN OUTCOMES MEASURES: Menstrual loss measured by the alkaline haematin method in three control menstrual periods and three menstrual periods during treatment; duration of bleeding; patient''s estimation of blood loss; sanitary towel usage; the occurrence of dysmenorrhoea; and unwanted events. RESULTS: Ethamsylate did not reduce mean menstrual blood loss whereas mefenamic acid reduced blood loss by 20% (mean blood loss 186 ml before treatment, 148 ml during treatment) and tranexamic acid reduced blood loss by 54% (mean blood loss 164 ml before treatment, 75 ml during treatment). Sanitary towel usage was significantly reduced in patients treated with mefenamic acid and tranexamic acid. CONCLUSIONS: Tranexamic acid given during menstruation is a safe and highly effective treatment for excessive bleeding. Patients with dysfunctional uterine bleeding should be offered medical treatment with tranexamic acid before a decision is made about surgery. 相似文献
90.
Primate terminal complement inhibitor homologues of human CD59 总被引:6,自引:0,他引:6
William L. Fodor Scott A. Rollins Stella Bianco-Caron Willis V. Burton Edward R. Guilmette Russell P. Rother George B. Zavoico Stephen P. Squinto 《Immunogenetics》1995,41(1):51-51
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L22862 (African green monkey CD59) and L22863 (baboon CD59) 相似文献