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341.
S. G. SUGUNA K. GOPALA RATHINAM A. R. RAJAVEL V. D HAN DA 《Medical and veterinary entomology》1994,8(1):88-94
Abstract. Anopheles subpictus Grassi is shown to comprise four reproductively distinct species, designated A, B, C and D, occurring sympatrically in villages of Pondicherry, southeast India.
Adult females were reared individually from wild larvae and examined for their morphological and chromosomal characters. Paracentric fixed inversions on the X-chromosome serve to distinguish the species cytogenetically, with no inversion heterozygotes (i.e. no interspecific hybrids) among totals of 717 species A (X+a ,+b ), 1863 species B (Xa, b), 869 species C (Xa,+b ) and 1365 species D (X +a ,b) identified.
Morphologically, diagnostic characters for each of the four species are seen in the egg float ridge number, larval mesothoracic seta 4, pupal seta 7-1 and the palpi of female adults. Species A. C and D immatures inhabit freshwater, whereas the malaria vector species B breeds in saltwater and was found only in coastal villages. 相似文献
Adult females were reared individually from wild larvae and examined for their morphological and chromosomal characters. Paracentric fixed inversions on the X-chromosome serve to distinguish the species cytogenetically, with no inversion heterozygotes (i.e. no interspecific hybrids) among totals of 717 species A (X+
Morphologically, diagnostic characters for each of the four species are seen in the egg float ridge number, larval mesothoracic seta 4, pupal seta 7-1 and the palpi of female adults. Species A. C and D immatures inhabit freshwater, whereas the malaria vector species B breeds in saltwater and was found only in coastal villages. 相似文献
342.
Parental care in mammals is influenced by sensory stimuli from infants, and by changes in the hormone levels of caretakers. To determine the responsiveness to infant cues in nonreproductive adult male common marmosets (Callithrix jacchus) with and without previous experience in caretaking, we exposed 12 males to newborn marmosets and assessed their cortisol plasma levels and behavioral response. Newborn marmosets housed in transparent enclosures were placed inside the cages of the adult male subjects. Males were exposed four times to two different experimental conditions: (a) newborn enclosures remained closed during the observation period and (b) newborn enclosures were opened during the observation period to allow direct social interaction by the adult males. Blood samples from adult males were collected after each behavioral observation trial to measure the levels of cortisol. The behavioral responses of adult males exposed to the closed and open newborn enclosures showed a significant difference only with respect to the frequency of displacements, where males moved among the quadrants of their own cages with greater frequency when the newborn enclosure was sealed. Experienced males approached newborn enclosures more frequently, spent more time in close proximity, and carried and recovered newborns more quickly than inexperienced males. The successive exposure to newborns increased the responsiveness in inexperienced males. The highest levels of plasma cortisol in adult males were recorded following periods of exposure to the sealed newborn enclosures. This suggests that successive exposure to newborns and previous alloparental caregiving experience while living in family groups influences the responsiveness of male marmosets to the sensory cues of newborns. Am. J. Primatol. 75:145‐152, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
343.
ESTELA NOVAK EDNA FREYMULLER HAAPALAINEN SOLANGE DA SILVA JOSE FRANCO DA SILVEIRA 《The Journal of eukaryotic microbiology》1988,35(3):375-378
Here we describe a method that allows the isolation of intact trypanosomatid symbionts in amounts sufficient for biochemical analysis. The isolated symbionts retain their characteristic morphological features and are reasonably free of subcellular debris. They actively incorporate [3H]leucine and [35S]methionine into proteins. Chloramphenicol and rifampicin at 50 μg/ml almost completely inhibit the incorporation of protein precursors. The inhibition of protein synthesis by the antibiotics provides direct evidence for the existence of a prokaryotic protein-synthesizing system in this unusual intracellular structure. The pattern of protein synthesis of the isolated symbionts is complex. Several symbiont polypeptides are absent or poorly represented in the flagellate. 相似文献
344.
ADRIAN A. BARNETT SARAH A. BOYLE MARILYN M. NORCONK SUZANNE PALMINTERI RICARDO R. SANTOS LIZA M. VEIGA THIAGO H.G. ALVIM MARK BOWLER JANICE CHISM ANTHONY DI FIORE EDUARDO FERNANDEZ‐DUQUE ANA C. P. GUIMARÃES AMY HARRISON‐LEVINE TORBJØRN HAUGAASEN SHAWN LEHMAN KATHERINE C. MACKINNON FABIANO R. DE MELO LEANDRO S. MOREIRA VIVIANE S. MOURA CARSON R. PHILLIPS LILIAM P. PINTO MARCIO PORT‐CARVALHO ELEONORE Z. F. SETZ CHRISTOPHER SHAFFER LÍVIA RODRIGUES DA SILVA SULEIMA DO S. B. DA SILVA RAFAELA F. SOARES CYNTHIA L. THOMPSON TATIANA M. VIEIRA ARIOENE VREEDZAAM SUZANNE E. WALKER‐PACHECO WILSON R. SPIRONELLO ANN MACLARNON STEPHEN F. FERRARI 《American journal of primatology》2012,74(12):1106-1127
Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a “local pattern” of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types. Am. J. Primatol. 74:1106‐1127, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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346.
The inter-relationship between the age of carrot roots at harvest and infection by Mycocentrospora acerina in storage 总被引:1,自引:0,他引:1
Infection of carrot roots by Mycocenlrospora acerina in chill storage (3.5 °C) following inoculation with chlamydospores was studied in 1973–74 and 1974–75. AREAS of intact periderm were only rarely infected, and the high level of periderm resistance predominated over other variables. However, wound infection tended to increase with depth of wound and with increasing age of the plants at harvest. Irrespective of age of root or depth of wound, roots were comparatively resistant to infection at harvest and early in storage, resistance being expressed as a restriction of mycelial growth on the wound surface or localisation of the lesion. Increasing susceptibility with time in storage, depth of wounds, or age at harvest, resulted in larger numbers of inoculated sites becoming infected and a more rapid development from localised to progressive lesions. 相似文献
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