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141.
STANISLAV LHOTA BRENT LOKEN STEPHANIE SPEHAR ERIC FELL ALEXANDR POSPĚCH NUNUK KASYANTO 《American journal of primatology》2012,74(3):193-198
Miller's Grizzled Langur (Presbytis hosei canicrus) is one of the least known and rarest primates in Borneo. With a limited geographic range along the central coast of East Kalimantan and the highly degraded Kutai National Park, its former stronghold, this subspecies is now extremely rare and has been listed as one of the world's 25 most endangered primates. From June 6 to August 2, 2011, we carried out both direct observation and camera trap surveys at two mineral springs (sepans) in the Wehea Forest, East Kutai district, East Kalimantan. Presbytis hosei canicrus was observed at the large sepan on 3 of 6 observation days and at the small sepan on 2 of 3 observation days with up to 11 individuals observed in a single day at a single site. Camera traps recorded a per day capture rate of 0.72 at the small sepan and 0.25 at the large sepan and a per photo capture rate of 0.50 and 0.005, respectively. These data suggest relatively frequent occurrence of P. h. canicrus at the sepans, but the langurs are rarely encountered elsewhere in the Wehea Forest. The discovery of P. h. canicrus in the Wehea Forest confirms the continued existence of this endangered primate and is the first solid evidence demonstrating that its geographic range extends further inland than previously thought. It is not known whether the population of P. h. canicrus within Wehea Forest is large and stable enough to be considered viable, but it is likely part of a larger population that may possibly occur across surrounding protected forests and logging concessions. Surveying this potentially large population, and securing its protection, should be a priority measure for ensuring the continued existence of P. h. canicrus. 相似文献
142.
H. J. N. SCHOENMAKERS CH. G. VAN BOHEMEN S. J. DIELEMAN 《Development, growth & differentiation》1981,23(2):125-135
Oocyte diameters and their frequency distribution, and various other data determined for the oestradiol-17 β treated female specimens of Asterias rubens proved to be significantly different from those for the control animals. The maturation index of the treated animals is 2.4, that of the control animals 1.4. Since the treated animals show a greater heterogeneity in development than the control animals, and because the diameter of the smallest oocytes is the same for both treated and control animals, a threshold size of the oocytes may be required before oocyte growth can be stimulated by oestradiol-17β, and before substances originating in the pyloric caeca are incorporated into the oocytes. Oestradiol-17β treatment caused a tenfold increase of the oestrone level in the ovaries, whereas a non-significant increase was observed in the pyloric caeca. This may indicate that in vivo oestradiol-17β is converted into oestrone in the ovaries but not in the pyloric caeca. 相似文献
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A double injection of PGF2α at two different dosage levels, 5 mg and 10 mg, eleven days apart, were compared with a combination of MAP-sponges and 5 mg or 10 mg PGF2α.The combination of MAP-sponges plus 10 mg PGF2α gave the best syn=chronization results (93,4%), as well as the best conception rate (84,9%) when ewes were inseminated on a fixed time basis 68 and 80 hours after treatment. 相似文献
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Peroxidase and polyphenol oxidase activities in malformed mango inflorescences of ‘Himsagar’ and ‘Bombay green’ oultivars wore found to be increased considerably following infection byFusarium moniliforme var.subglutinans. Whether such increased activities were due to their synthesis by the pathogen or the host, or both, was not studied although it was found that the pathogen was incapable of producing the enzymesin vitro. The activities of both the enzymes in infected tissues were found to increase considerably during the experimental period. It was found that activities of polyphenol oxidase were inhibited in the presence of sodium diethyldithiocarbamate and phenylthiourea; the former acted as chelating agent of Cu of the enzymes and the latter as a competitive inhibitor. Similarly, peroxidase activity was found to be inhibited by cycloheximide which acted as inhibitor of enzyme protein synthesis. The fact that the ‘Himsagar’ cultivar showed greater enzyme activity than the ‘Bombay green’ cultivar possibly suggests its higher resistance to the pathogen. 相似文献
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Dionyssios CH. Perdikis† Argyro A. Fantinou Dionyssios P. Lykouressis† 《Physiological Entomology》2003,28(4):331-339
Abstract. This study investigated the existence of rate isomorphy (the constant allocation of relative times to different stages of development under different abiotic conditions) in Macrolophus pygmaeus (Hemiptera: Miridae; a phytophagous and predatory insect). Replicated data were used from a range of temperatures regarding (i) the developmental period of each nymphal stage in relation to the total duration of nymph development, when feeding on three host plants either with different prey species or without prey, and (ii) its egg, total nymphal and preoviposition period, on two host plants, with different prey species. The proportion of time required for the development of each nymphal stage of M. pygmaeus is not different among the temperatures or the kind of food available. These proportions ranged among the different host plants, temperatures and prey presence/absence from 17.3–21.8% in the first, 14.5–18.8% in the second, 14.2–18.3% in the third, 16.5–21.0% in the fourth and from 25.4–30.6% in the fifth nymphal stage. Thus, temperature does not significantly affect the proportion of time spent in each nymphal stage and rate isomorphy exists in nymphal development. This phenomenon was also investigated using data from the literature, and it also occurs in several other Hemiptera species. Therefore, there appears to be a constant time allocation in the nymphal development of the higher taxonomic groups of insects. However, for M. pygmaeus, rate isomorphy does not hold when considering egg‐to‐egg development and the relative duration of times to egg hatch, total nymphal development and preoviposition period. The ecophysiological implications of this rate isomorphy phenomenon are discussed in relation to endocrinological mechanisms. Apart from its theoretical interest, the existence of rate isomorphy simplifies studies on the rate of development and the estimation of thermal constants of an insect, which are essential for the prediction of insect population dynamics. It is also proposed that the term ‘rate isomorphy’ does not strictly describe the phenomenon, and it is suggested that ‘constant rate allocation’ would be a more suitable term. 相似文献